diff --git a/EU2Mod_MB/src/main/java/itesla/converter/ModelicaModel.java b/EU2Mod_MB/src/main/java/itesla/converter/ModelicaModel.java
index 0af07f2b..ce5fae3a 100644
--- a/EU2Mod_MB/src/main/java/itesla/converter/ModelicaModel.java
+++ b/EU2Mod_MB/src/main/java/itesla/converter/ModelicaModel.java
@@ -549,9 +549,13 @@ public void Connection() {
                     connRight = model.nameModelica + "_" + Blocks[Link[i][1] - 1].GraphicalNumber.toString() + ".u" + Link[i][2].toString();
                 }
             }
-            Blocks[Link[i][1] - 1].UsedInputPins.set(Link[i][2] - 1, true);
-            conn = conn + connLeft + ", " + connRight + ");";
-            outputConnection.add(conn);
+            if ((Link[i][2]) <=  Blocks[Link[i][1] - 1].UsedInputPins.size()) {
+                Blocks[Link[i][1] - 1].UsedInputPins.set(Link[i][2] - 1, true);
+                conn = conn + connLeft + ", " + connRight + ");";
+                outputConnection.add(conn);
+            } else {
+                System.err.println("Connection - file: " + pathEu + ", id: " + Blocks[Link[i][1] - 1].idEu + ",  inputPins: " + Blocks[Link[i][1] - 1].UsedInputPins + ", inputPins size: " + Blocks[Link[i][1] - 1].UsedInputPins.size() + ", but the index to-be set is: " + Link[i][2]);
+            }
         }
     }
 
@@ -601,8 +605,12 @@ public void InputConnection() {
                         }
                     }
                     conn = "  connect(" + connLeft + ", " + connRight + ");";
-                    Blocks[i].UsedInputPins.set(indConnRight - 1, true);
-                    outputInputConnection.add(conn);
+                    if (indConnRight <= Blocks[i].UsedInputPins.size()) {
+                        Blocks[i].UsedInputPins.set(indConnRight - 1, true);
+                        outputInputConnection.add(conn);
+                    } else {
+                        System.err.println("InputConnection - file: " + pathEu + ", id: " + Blocks[i].idEu + ",  inputPins: " + Blocks[i].UsedInputPins + ", inputPins size: " + Blocks[i].UsedInputPins.size() + ",  but the index to-be set is: " + (indConnRight - 1));
+                    }
                 }
             }
         }
diff --git a/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EchUtil.java b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EchUtil.java
index dd14c006..56cb658c 100644
--- a/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EchUtil.java
+++ b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EchUtil.java
@@ -11,6 +11,7 @@
 
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.Objects;
 import java.util.Set;
 import java.util.stream.StreamSupport;
 
@@ -183,4 +184,53 @@ public static boolean isInMainCc(Branch branch, boolean noswitch) {
         return (ConnectedComponents.getCcNum(EchUtil.getBus(branch.getTerminal1(), noswitch)) == Component.MAIN_NUM)
                 && (ConnectedComponents.getCcNum(EchUtil.getBus(branch.getTerminal2(), noswitch)) == Component.MAIN_NUM);
     }
+
+    /**
+     * given an iIDM HVDC line , returns its DC voltage to be used with Eurostag
+     * Multiplying  the line's nominalV by 2 corresponds to the fact that iIDM refers to the cable-ground voltage
+     * while Eurostag regulations to the cable-cable voltage
+     */
+    public static float getHvdcLineDcVoltage(HvdcLine line) {
+        Objects.requireNonNull(line);
+        return line.getNominalV() * 2.0f;
+    }
+
+    public static boolean isPMode(HvdcConverterStation vscConv, HvdcLine hvdcLine) {
+        Objects.requireNonNull(vscConv);
+        Objects.requireNonNull(hvdcLine);
+        HvdcConverterStation side1Conv = hvdcLine.getConverterStation1();
+        HvdcConverterStation side2Conv = hvdcLine.getConverterStation2();
+        if ((hvdcLine.getConvertersMode().equals(HvdcLine.ConvertersMode.SIDE_1_RECTIFIER_SIDE_2_INVERTER))
+                && (vscConv.getId().equals(side1Conv.getId()))) {
+            return true;
+        }
+        if ((hvdcLine.getConvertersMode().equals(HvdcLine.ConvertersMode.SIDE_1_INVERTER_SIDE_2_RECTIFIER))
+                && (vscConv.getId().equals(side2Conv.getId()))) {
+            return true;
+        }
+        return false;
+    }
+
+    public static HvdcConverterStation getPStation(HvdcLine hvdcLine) {
+        Objects.requireNonNull(hvdcLine);
+        if (hvdcLine.getConvertersMode().equals(HvdcLine.ConvertersMode.SIDE_1_RECTIFIER_SIDE_2_INVERTER)) {
+            return hvdcLine.getConverterStation1();
+        }
+        if (hvdcLine.getConvertersMode().equals(HvdcLine.ConvertersMode.SIDE_1_INVERTER_SIDE_2_RECTIFIER)) {
+            return hvdcLine.getConverterStation2();
+        }
+        return null;
+    }
+
+    public static HvdcConverterStation getVStation(HvdcLine hvdcLine) {
+        Objects.requireNonNull(hvdcLine);
+        if (hvdcLine.getConvertersMode().equals(HvdcLine.ConvertersMode.SIDE_1_RECTIFIER_SIDE_2_INVERTER)) {
+            return hvdcLine.getConverterStation2();
+        }
+        if (hvdcLine.getConvertersMode().equals(HvdcLine.ConvertersMode.SIDE_1_INVERTER_SIDE_2_RECTIFIER)) {
+            return hvdcLine.getConverterStation1();
+        }
+        return null;
+    }
+
 }
diff --git a/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagDictionary.java b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagDictionary.java
index 866a4b9c..8d87a0d6 100644
--- a/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagDictionary.java
+++ b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagDictionary.java
@@ -13,6 +13,8 @@
 import eu.itesla_project.eurostag.network.EsgBranchName;
 import com.powsybl.iidm.network.*;
 import com.powsybl.iidm.network.util.Identifiables;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.BufferedReader;
 import java.io.BufferedWriter;
@@ -31,6 +33,8 @@
  */
 public final class EurostagDictionary {
 
+    private static final Logger LOGGER = LoggerFactory.getLogger(EurostagDictionary.class);
+
     private static final EurostagNamingStrategy NAMING_STRATEGY = new DicoEurostagNamingStrategyFactory().create();
 
     private final BiMap<String, String> iidmId2esgId;
@@ -54,16 +58,19 @@ public static EurostagDictionary create(Network network, BranchParallelIndexes p
         Set<String> generatorIds = Identifiables.sort(network.getGenerators()).stream().map(Generator::getId).collect(Collectors.toSet());
         Set<String> shuntIds = Identifiables.sort(network.getShunts()).stream().map(ShuntCompensator::getId).collect(Collectors.toSet());
         Set<String> svcIds = Identifiables.sort(network.getStaticVarCompensators()).stream().map(StaticVarCompensator::getId).collect(Collectors.toSet());
+        Set<String> converterStationsIds = Identifiables.sort(network.getVscConverterStations()).stream().map(VscConverterStation::getId).collect(Collectors.toSet());
 
         NAMING_STRATEGY.fillDictionary(dictionary, EurostagNamingStrategy.NameType.NODE, busIds);
         NAMING_STRATEGY.fillDictionary(dictionary, EurostagNamingStrategy.NameType.GENERATOR, generatorIds);
         NAMING_STRATEGY.fillDictionary(dictionary, EurostagNamingStrategy.NameType.LOAD, loadIds);
         NAMING_STRATEGY.fillDictionary(dictionary, EurostagNamingStrategy.NameType.BANK, shuntIds);
         NAMING_STRATEGY.fillDictionary(dictionary, EurostagNamingStrategy.NameType.SVC, svcIds);
+        NAMING_STRATEGY.fillDictionary(dictionary, EurostagNamingStrategy.NameType.VSC, converterStationsIds);
 
         for (DanglingLine dl : Identifiables.sort(network.getDanglingLines())) {
             // skip if not in the main connected component
             if (config.isExportMainCCOnly() && !EchUtil.isInMainCc(dl, config.isNoSwitch())) {
+                LOGGER.trace("dangling line not mapped, not in main component: {}", dl.getId());
                 continue;
             }
             ConnectionBus bus1 = ConnectionBus.fromTerminal(dl.getTerminal(), config, fakeNodes);
@@ -79,6 +86,7 @@ public static EurostagDictionary create(Network network, BranchParallelIndexes p
                 Bus bus2 = EchUtil.getBus2(vl, sw.getId(), config);
                 // skip switches not in the main connected component
                 if (config.isExportMainCCOnly() && (!EchUtil.isInMainCc(bus1) || !EchUtil.isInMainCc(bus2))) {
+                    LOGGER.trace("switch not mapped, not in main component: {}", sw.getId());
                     continue;
                 }
                 dictionary.addIfNotExist(sw.getId(),
@@ -91,6 +99,7 @@ public static EurostagDictionary create(Network network, BranchParallelIndexes p
         for (Line l : Identifiables.sort(network.getLines())) {
             // skip lines not in the main connected component
             if (config.isExportMainCCOnly() && !EchUtil.isInMainCc(l, config.isNoSwitch())) {
+                LOGGER.trace("line not mapped, not in main component: {}", l.getId());
                 continue;
             }
             ConnectionBus bus1 = ConnectionBus.fromTerminal(l.getTerminal1(), config, fakeNodes);
@@ -104,6 +113,7 @@ public static EurostagDictionary create(Network network, BranchParallelIndexes p
         for (TwoWindingsTransformer twt : Identifiables.sort(network.getTwoWindingsTransformers())) {
             // skip transformers not in the main connected component
             if (config.isExportMainCCOnly() && !EchUtil.isInMainCc(twt, config.isNoSwitch())) {
+                LOGGER.trace("two windings transformer not mapped, not in main component: {}", twt.getId());
                 continue;
             }
             ConnectionBus bus1 = ConnectionBus.fromTerminal(twt.getTerminal1(), config, fakeNodes);
@@ -114,6 +124,7 @@ public static EurostagDictionary create(Network network, BranchParallelIndexes p
         }
 
         for (ThreeWindingsTransformer twt : Identifiables.sort(network.getThreeWindingsTransformers())) {
+            LOGGER.error("NOT YET IMPLEMENTED");
             throw new AssertionError("TODO");
         }
 
@@ -133,7 +144,9 @@ private EurostagDictionary(Map<String, String> iidmId2esgId, EurostagEchExportCo
 
     public void add(String iidmId, String esgId) {
         if (iidmId2esgId.containsKey(iidmId)) {
-            throw new RuntimeException("IIDM id '" + iidmId + "' already exists in the dictionary");
+            String errorMsg = "IIDM id '" + iidmId + "' already exists in the dictionary";
+            LOGGER.error(errorMsg);
+            throw new RuntimeException(errorMsg);
         }
         iidmId2esgId.put(iidmId, esgId);
     }
@@ -141,8 +154,10 @@ public void add(String iidmId, String esgId) {
     public void addIfNotExist(String iidmId, String esgId) {
         if (!iidmId2esgId.containsKey(iidmId)) {
             if (iidmId2esgId.inverse().containsKey(esgId)) {
-                throw new RuntimeException("Esg id '" + esgId + "' is already associated to IIDM id '"
-                        + iidmId2esgId.inverse().get(esgId) + "' impossible to associate it to IIDM id '" + iidmId + "'");
+                String errorMsg = "Esg id '" + esgId + "' is already associated to IIDM id '"
+                        + iidmId2esgId.inverse().get(esgId) + "' impossible to associate it to IIDM id '" + iidmId + "'";
+                LOGGER.error(errorMsg);
+                throw new RuntimeException(errorMsg);
             }
             iidmId2esgId.put(iidmId, esgId);
         }
@@ -150,14 +165,18 @@ public void addIfNotExist(String iidmId, String esgId) {
 
     public String getEsgId(String iidmId) {
         if (!iidmId2esgId.containsKey(iidmId)) {
-            throw new RuntimeException("IIDM id '" + iidmId + "' + not found in the dictionary");
+            String errorMsg = "IIDM id '" + iidmId + "' + not found in the dictionary";
+            LOGGER.error(errorMsg);
+            throw new RuntimeException(errorMsg);
         }
         return iidmId2esgId.get(iidmId);
     }
 
     public String getIidmId(String esgId) {
         if (!iidmId2esgId.containsValue(esgId)) {
-            throw new RuntimeException("ESG id '" + esgId + "' + not found in the dictionary");
+            String errorMsg = "ESG id '" + esgId + "' + not found in the dictionary";
+            LOGGER.error(errorMsg);
+            throw new RuntimeException(errorMsg);
         }
         return iidmId2esgId.inverse().get(esgId);
     }
@@ -187,6 +206,7 @@ public void load(Path file) {
                 }
             }
         } catch (IOException e) {
+            LOGGER.error(e.getMessage(), e);
             throw new RuntimeException(e);
         }
     }
@@ -200,6 +220,7 @@ public void dump(Path file) {
                 }
             }
         } catch (IOException e) {
+            LOGGER.error(e.getMessage(), e);
             throw new RuntimeException(e);
         }
     }
diff --git a/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExport.java b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExport.java
index 1b583894..f511a494 100644
--- a/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExport.java
+++ b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExport.java
@@ -26,7 +26,7 @@
 /**
  * @author Geoffroy Jamgotchian <geoffroy.jamgotchian at rte-france.com>
  */
-public class EurostagEchExport {
+public class EurostagEchExport implements EurostagEchExporter {
 
     private static final Logger LOGGER = LoggerFactory.getLogger(EurostagEchExport.class);
 
@@ -38,16 +38,16 @@ public class EurostagEchExport {
     /**
      * epsilon value for susceptance
      */
-    public static final float B_EPSILON = 0.00001f;
+    public static final float B_EPSILON = 0.000001f;
 
     private static final String XNODE_V_PROPERTY = "xnode_v";
     private static final String XNODE_ANGLE_PROPERTY = "xnode_angle";
 
-    private final Network network;
-    private final EurostagEchExportConfig config;
-    private final BranchParallelIndexes parallelIndexes;
-    private final EurostagDictionary dictionary;
-    private final EurostagFakeNodes fakeNodes;
+    protected final Network network;
+    protected final EurostagEchExportConfig config;
+    protected final BranchParallelIndexes parallelIndexes;
+    protected final EurostagDictionary dictionary;
+    protected final EurostagFakeNodes fakeNodes;
 
     public EurostagEchExport(Network network, EurostagEchExportConfig config, BranchParallelIndexes parallelIndexes, EurostagDictionary dictionary, EurostagFakeNodes fakeNodes) {
         this.network = Objects.requireNonNull(network);
@@ -74,6 +74,10 @@ private void createAreas(EsgNetwork esgNetwork) {
         for (Country c : network.getCountries()) {
             esgNetwork.addArea(new EsgArea(new Esg2charName(c.toString()), EsgArea.Type.AC));
         }
+
+        if (network.getHvdcLineCount() > 0) {
+            esgNetwork.addArea(new EsgArea(new Esg2charName("DC"), EsgArea.Type.DC));
+        }
     }
 
     private EsgNode createNode(String busId, String countryIsoCode, float nominalV, float v, float angle, boolean slackBus) {
@@ -194,14 +198,53 @@ private void createLines(EsgNetwork esgNetwork, EsgGeneralParameters parameters)
                 LOGGER.warn("not in main component, skipping Line: {}", l.getId());
                 continue;
             }
-
+            // It is better to model branches as -normal- lines because it is impossible to open dissymmetrical branches and to do short-circuit on them
+            // Therefore, normal lines are created:
+            // - If the G and B are the same on each side of the line, even if the G are not 0
+            // - If the B are not the same but the G are 0
+            // The code could be extended to handle the case where the B are not the same and the G are not the same
             ConnectionBus bus1 = ConnectionBus.fromTerminal(l.getTerminal1(), config, fakeNodes);
             ConnectionBus bus2 = ConnectionBus.fromTerminal(l.getTerminal2(), config, fakeNodes);
-            // if the admittance are the same in the both side of PI line model
-            if (Math.abs(l.getG1() - l.getG2()) < G_EPSILON && Math.abs(l.getB1() - l.getB2()) < B_EPSILON) {
-                //...create a simple line
+            if (Math.abs(l.getG1() - l.getG2()) < G_EPSILON
+                    && (Math.abs(l.getB1() - l.getB2()) < B_EPSILON
+                       || (Math.abs(l.getG1()) < G_EPSILON && Math.abs(l.getG2()) < G_EPSILON))) {
+                ConnectionBus bNode = null;
+                float b;
+                float diffB = 0f;
+                float g = (l.getG1() + l.getG2()) / 2.0f;
+                float vNom = 0f;
+                if (l.getB1() < l.getB2() - B_EPSILON) {
+                    bNode = bus2;
+                    b = l.getB1();
+                    diffB = l.getB2() - l.getB1();
+                    vNom = l.getTerminal2().getVoltageLevel().getNominalV();
+                } else if (l.getB2() < l.getB1() - B_EPSILON) {
+                    bNode = bus1;
+                    b = l.getB2();
+                    diffB = l.getB1() - l.getB2();
+                    vNom = l.getTerminal1().getVoltageLevel().getNominalV();
+                } else {
+                    b = (l.getB1() + l.getB2()) / 2.0f;
+                }
+
                 esgNetwork.addLine(createLine(l.getId(), bus1, bus2, l.getTerminal1().getVoltageLevel().getNominalV(),
-                        l.getR(), l.getX(), l.getG1(), l.getB1(), parameters));
+                        l.getR(), l.getX(), g, b, parameters));
+
+                if (bNode != null) {
+                    //create a dummy shunt attached to bNode
+                    String fictionalShuntId = "FKSH" + l.getId();
+                    addToDictionary(fictionalShuntId, dictionary, EurostagNamingStrategy.NameType.BANK);
+
+                    int ieleba = 1;
+                    float plosba = 0.f;
+                    float rcapba = vNom * vNom * diffB;
+                    int imaxba = 1;
+                    EsgCapacitorOrReactorBank.RegulatingMode xregba = EsgCapacitorOrReactorBank.RegulatingMode.NOT_REGULATING;
+
+                    esgNetwork.addCapacitorsOrReactorBanks(new EsgCapacitorOrReactorBank(new Esg8charName(dictionary.getEsgId(fictionalShuntId)),
+                            new Esg8charName(dictionary.getEsgId(bNode.getId())),
+                            ieleba, plosba, rcapba, imaxba, xregba));
+                }
             } else {
                 EsgBranchConnectionStatus status = getStatus(bus1, bus2);
                 if (status.equals(EsgBranchConnectionStatus.CLOSED_AT_BOTH_SIDE)) {
@@ -233,16 +276,13 @@ private void createLines(EsgNetwork esgNetwork, EsgGeneralParameters parameters)
     private EsgDetailedTwoWindingTransformer.Tap createTap(TwoWindingsTransformer twt, int iplo, float rho, float dr, float dx,
                                                            float dephas, float rate, EsgGeneralParameters parameters) {
         float nomiU2 = twt.getTerminal2().getVoltageLevel().getNominalV();
-        float rhoI = twt.getRatedU2() / twt.getRatedU1() * rho;
-        float uno1 = nomiU2 / rhoI;
+        float uno1 = nomiU2 / rho;
         float uno2 = nomiU2;
-        float r = twt.getR() * (1 + dr / 100.0f);
-        float x = twt.getX() * (1 + dx / 100.0f);
 
         //...mTrans.getR() = Get the nominal series resistance specified in Ω at the secondary voltage side.
         float zb2 = (float) (Math.pow(nomiU2, 2) / parameters.getSnref());
-        float rpu2 = r / zb2;  //...total line resistance  [p.u.](Base snref)
-        float xpu2 = x / zb2;  //...total line reactance   [p.u.](Base snref)
+        float rpu2 = dr / zb2;  //...total line resistance  [p.u.](Base snref)
+        float xpu2 = dx / zb2;  //...total line reactance   [p.u.](Base snref)
 
         //...leakage impedance [%] (base rate)
         float ucc;
@@ -286,6 +326,74 @@ private void createAdditionalBank(EsgNetwork esgNetwork, TwoWindingsTransformer
 
     }
 
+    private float getRtcRho1(TwoWindingsTransformer twt, int p) {
+        float rho1 = twt.getRatedU2() / twt.getRatedU1();
+        if (twt.getRatioTapChanger() != null) {
+            rho1 *= twt.getRatioTapChanger().getStep(p).getRho();
+        }
+        if (twt.getPhaseTapChanger() != null) {
+            rho1 *= twt.getPhaseTapChanger().getCurrentStep().getRho();
+        }
+        return rho1;
+    }
+
+    private float getPtcRho1(TwoWindingsTransformer twt, int p) {
+        float rho1 = twt.getRatedU2() / twt.getRatedU1();
+        if (twt.getRatioTapChanger() != null) {
+            rho1 *= twt.getRatioTapChanger().getCurrentStep().getRho();
+        }
+        if (twt.getPhaseTapChanger() != null) {
+            rho1 *= twt.getPhaseTapChanger().getStep(p).getRho();
+        }
+        return rho1;
+    }
+
+    private float getValue(float initialValue, float rtcStepValue, float ptcStepValue) {
+        return initialValue * (1 + rtcStepValue / 100) * (1 + ptcStepValue / 100);
+    }
+
+    private float getRtcR(TwoWindingsTransformer twt, int p) {
+        return getValue(twt.getR(),
+                twt.getRatioTapChanger() != null ? twt.getRatioTapChanger().getStep(p).getR() : 0,
+                twt.getPhaseTapChanger() != null ? twt.getPhaseTapChanger().getCurrentStep().getR() : 0);
+    }
+
+    private float getPtcR(TwoWindingsTransformer twt, int p) {
+        return getValue(twt.getR(),
+                twt.getRatioTapChanger() != null ? twt.getRatioTapChanger().getCurrentStep().getR() : 0,
+                twt.getPhaseTapChanger() != null ? twt.getPhaseTapChanger().getStep(p).getR() : 0);
+    }
+
+    private float getRtcX(TwoWindingsTransformer twt, int p) {
+        return getValue(twt.getX(),
+                twt.getRatioTapChanger() != null ? twt.getRatioTapChanger().getStep(p).getX() : 0,
+                twt.getPhaseTapChanger() != null ? twt.getPhaseTapChanger().getCurrentStep().getX() : 0);
+    }
+
+    private float getPtcX(TwoWindingsTransformer twt, int p) {
+        return getValue(twt.getX(),
+                twt.getRatioTapChanger() != null ? twt.getRatioTapChanger().getCurrentStep().getX() : 0,
+                twt.getPhaseTapChanger() != null ? twt.getPhaseTapChanger().getStep(p).getX() : 0);
+    }
+
+    private float getR(TwoWindingsTransformer twt) {
+        return getValue(twt.getR(),
+                twt.getRatioTapChanger() != null ? twt.getRatioTapChanger().getCurrentStep().getR() : 0,
+                twt.getPhaseTapChanger() != null ? twt.getPhaseTapChanger().getCurrentStep().getR() : 0);
+    }
+
+    private float getG1(TwoWindingsTransformer twt) {
+        return getValue(config.isSpecificCompatibility() ? twt.getG() / 2 : twt.getG(),
+                twt.getRatioTapChanger() != null ? twt.getRatioTapChanger().getCurrentStep().getG() : 0,
+                twt.getPhaseTapChanger() != null ? twt.getPhaseTapChanger().getCurrentStep().getG() : 0);
+    }
+
+    private float getB1(TwoWindingsTransformer twt) {
+        return getValue(config.isSpecificCompatibility() ? twt.getB() / 2 : twt.getB(),
+                twt.getRatioTapChanger() != null ? twt.getRatioTapChanger().getCurrentStep().getB() : 0,
+                twt.getPhaseTapChanger() != null ? twt.getPhaseTapChanger().getCurrentStep().getB() : 0);
+    }
+
     private void createTransformers(EsgNetwork esgNetwork, EsgGeneralParameters parameters) {
         Set<String> additionalBanksIds = new HashSet<>();
 
@@ -329,13 +437,16 @@ private void createTransformers(EsgNetwork esgNetwork, EsgGeneralParameters para
             EsgDetailedTwoWindingTransformer.RegulatingMode regulatingMode = EsgDetailedTwoWindingTransformer.RegulatingMode.NOT_REGULATING;
             Esg8charName zbusr = null; //...regulated node name (if empty, no tap change)
             float voltr = Float.NaN;
-            int ktpnom; //...nominal tap number is not available in IIDM. Take th median plot by default
-            int ktap8;  //...initial tap position (tap number) (Ex: 10)
+            int ktpnom = 1; //...nominal tap number is not available in IIDM. Take th median plot by default
+            int ktap8 = 1;  //...initial tap position (tap number) (Ex: 10)
             List<EsgDetailedTwoWindingTransformer.Tap> taps = new ArrayList<>();
 
             RatioTapChanger rtc = twt.getRatioTapChanger();
             PhaseTapChanger ptc = twt.getPhaseTapChanger();
-            if (rtc != null && ptc == null) {
+            if ((rtc != null && ptc == null) || (rtc != null && ptc != null && rtc.isRegulating() && !ptc.isRegulating())) {
+                if (rtc != null && ptc != null) {
+                    LOGGER.warn("both ptc and rtc exist on two winding transformer {}. Only the rtc is kept because it is regulating.", twt.getId());
+                }
                 if (rtc.isRegulating()) {
                     ConnectionBus regulatingBus = ConnectionBus.fromTerminal(rtc.getRegulationTerminal(), config, null);
                     if (regulatingBus.getId() != null) {
@@ -348,10 +459,14 @@ private void createTransformers(EsgNetwork esgNetwork, EsgGeneralParameters para
                 ktpnom = rtc.getStepCount() / 2 + 1;
                 for (int p = rtc.getLowTapPosition(); p <= rtc.getHighTapPosition(); p++) {
                     int iplo = p - rtc.getLowTapPosition() + 1;
-                    taps.add(createTap(twt, iplo, rtc.getStep(p).getRho(), rtc.getStep(p).getR(), rtc.getStep(p).getX(), 0f, rate, parameters));
+                    taps.add(createTap(twt, iplo, getRtcRho1(twt, p), getRtcR(twt, p), getRtcX(twt, p), 0f, rate, parameters));
+                }
+
+            } else if (ptc != null || rtc != null) {
+                if (rtc != null && ptc != null) {
+                    LOGGER.warn("both ptc and rtc exist on two winding transformer {}. Only the ptc is kept.", twt.getId());
                 }
 
-            } else if (ptc != null && rtc == null) {
                 if (ptc.getRegulationMode() == PhaseTapChanger.RegulationMode.CURRENT_LIMITER && ptc.isRegulating()) {
                     String regulbus = EchUtil.getBus(ptc.getRegulationTerminal(), config).getId();
                     if (regulbus.equals(bus1.getId())) {
@@ -368,32 +483,25 @@ private void createTransformers(EsgNetwork esgNetwork, EsgGeneralParameters para
                 ktpnom = ptc.getStepCount() / 2 + 1;
                 for (int p = ptc.getLowTapPosition(); p <= ptc.getHighTapPosition(); p++) {
                     int iplo = p - ptc.getLowTapPosition() + 1;
-                    taps.add(createTap(twt, iplo, ptc.getStep(p).getRho(), ptc.getStep(p).getR(), ptc.getStep(p).getX(), ptc.getStep(p).getAlpha(), rate, parameters));
+                    taps.add(createTap(twt, iplo, getPtcRho1(twt, p), getPtcR(twt, p), getPtcX(twt, p), ptc.getStep(p).getAlpha(), rate, parameters));
                 }
             } else if (rtc == null && ptc == null) {
-                ktap8 = 1;
-                ktpnom = 1;
-                taps.add(createTap(twt, 1, 1f, 0f, 0f, 0f, rate, parameters));
-            } else {
-                throw new RuntimeException("Transformer " + twt.getId() + "  with voltage and phase tap changer not yet supported");
+                taps.add(createTap(twt, 1, twt.getRatedU2() / twt.getRatedU1(), twt.getR(), twt.getX(), 0f, rate, parameters));
             }
 
             // trick to handle the fact that Eurostag model allows only the impedance to change and not the resistance.
             // As an approximation, the resistance is fixed to the value it has for the initial step,
             // but discrepancies will occur if the step is changed.
             if ((ptc != null) || (rtc != null)) {
-                float dr = (rtc != null) ? rtc.getStep(rtc.getTapPosition()).getR() : ptc.getStep(ptc.getTapPosition()).getR();
-                float tapAdjustedR = twt.getR() * (1 + dr / 100.0f);
+                float tapAdjustedR = getR(twt);
                 float rpu2Adjusted = (tapAdjustedR * parameters.getSnref()) / nomiU2 / nomiU2;
                 pcu = rpu2Adjusted * rate * 100f / parameters.getSnref();
 
-                float dg = (rtc != null) ? rtc.getStep(rtc.getTapPosition()).getG() : ptc.getStep(ptc.getTapPosition()).getG();
-                float tapAdjustedG = twt.getG() * (1 + dg / 100.0f);
+                float tapAdjustedG = getG1(twt);
                 float gpu2Adjusted = (tapAdjustedG / parameters.getSnref()) * nomiU2 * nomiU2;
                 pfer = 10000f * ((float) Math.sqrt(gpu2Adjusted) / rate) * (parameters.getSnref() / 100f);
 
-                float db = (rtc != null) ? rtc.getStep(rtc.getTapPosition()).getB() : ptc.getStep(ptc.getTapPosition()).getB();
-                float tapAdjustedB = twt.getB() * (1 + db / 100.0f);
+                float tapAdjustedB = getB1(twt);
                 float bpu2Adjusted = (tapAdjustedB / parameters.getSnref()) * nomiU2 * nomiU2;
                 modgb = (float) Math.sqrt(Math.pow(gpu2Adjusted, 2.f) + Math.pow(bpu2Adjusted, 2.f));
                 cmagn = 10000 * (modgb / rate) * (parameters.getSnref() / 100f);
@@ -495,14 +603,21 @@ private void createGenerators(EsgNetwork esgNetwork) {
             boolean isQminQmaxInverted = g.getReactiveLimits().getMinQ(pgen) > g.getReactiveLimits().getMaxQ(pgen);
             if (isQminQmaxInverted) {
                 LOGGER.warn("inverted qmin {} and qmax {} values for generator {}", g.getReactiveLimits().getMinQ(pgen), g.getReactiveLimits().getMaxQ(pgen), g.getId());
+                qgen = -g.getTerminal().getQ();
+            }
+            boolean isVoltageRegulatorOn = g.isVoltageRegulatorOn();
+            // Exception for out of bound regulating generators
+            if (config.isSpecificCompatibility() && (g.getTargetP() < 0.0001) && (g.getMinP() > 0.0001)) {
+                isVoltageRegulatorOn = false;
+                LOGGER.warn("out of bound regulating generator {}, targetP {}, minP {} : turn off its voltage regulation", g.getId(), g.getTargetP(), g.getMinP());
             }
             // in case qmin and qmax are inverted, take out the unit from the voltage regulation if it has a target Q
             // and open widely the Q interval
             float qgmin = (config.isNoGeneratorMinMaxQ() || isQminQmaxInverted) ? -9999 : g.getReactiveLimits().getMinQ(pgen);
             float qgmax = (config.isNoGeneratorMinMaxQ() || isQminQmaxInverted) ? 9999 : g.getReactiveLimits().getMaxQ(pgen);
             EsgRegulatingMode mode = (isQminQmaxInverted && !Float.isNaN(qgen)) ? EsgRegulatingMode.NOT_REGULATING :
-                    (g.isVoltageRegulatorOn() && g.getTargetV() >= 0.1 ? EsgRegulatingMode.REGULATING : EsgRegulatingMode.NOT_REGULATING);
-            float vregge = (isQminQmaxInverted && !Float.isNaN(qgen)) ? Float.NaN : (g.isVoltageRegulatorOn() ? g.getTargetV() : Float.NaN);
+                    (isVoltageRegulatorOn && g.getTargetV() >= 0.1 ? EsgRegulatingMode.REGULATING : EsgRegulatingMode.NOT_REGULATING);
+            float vregge = (isQminQmaxInverted && !Float.isNaN(qgen)) ? Float.NaN : (isVoltageRegulatorOn ? g.getTargetV() : Float.NaN);
             float qgensh = 1.f;
 
             //fails, when noSwitch is true !!
@@ -562,7 +677,7 @@ private void createStaticVarCompensators(EsgNetwork esgNetwork) {
             if (!config.isSvcAsFixedInjectionInLF()) {
                 binit = svc.getReactivePowerSetPoint();
             } else {
-                binit = -svc.getTerminal().getQ();
+                binit = svc.getTerminal().getQ();
                 Bus svcBus = EchUtil.getBus(svc.getTerminal(), config);
                 if ((svcBus != null) && (Math.abs(svcBus.getV()) > 0.0f)) {
                     binit = binit * (float) Math.pow(vlNomVoltage / svcBus.getV(), 2);
@@ -577,6 +692,172 @@ private void createStaticVarCompensators(EsgNetwork esgNetwork) {
         }
     }
 
+    //add a new couple (iidmId, esgId). EsgId is built from iidmId using a simple cut-name mapping strategy
+    private String addToDictionary(String iidmId, EurostagDictionary dictionary, EurostagNamingStrategy.NameType nameType) {
+        if (dictionary.iidmIdExists(iidmId)) {
+            throw new RuntimeException("iidmId " + iidmId + " already exists in dictionary");
+        }
+        String esgId = iidmId.length() > nameType.getLength() ? iidmId.substring(0, nameType.getLength())
+                : Strings.padEnd(iidmId, nameType.getLength(), ' ');
+        int counter = 0;
+        while (dictionary.esgIdExists(esgId)) {
+            String counterStr = Integer.toString(counter++);
+            if (counterStr.length() > nameType.getLength()) {
+                throw new RuntimeException("Renaming fatal error " + iidmId + " -> " + esgId);
+            }
+            esgId = esgId.substring(0, nameType.getLength() - counterStr.length()) + counterStr;
+        }
+        dictionary.add(iidmId, esgId);
+        return esgId;
+    }
+
+    protected float zeroIfNanOrValue(float value) {
+        return Float.isNaN(value) ? 0 : value;
+    }
+
+    protected EsgACDCVscConverter createACDCVscConverter(VscConverterStation vscConv, HvdcLine hline, Esg8charName vscConvDcName) {
+        Objects.requireNonNull(vscConv);
+        Objects.requireNonNull(hline, "no hvdc line connected to VscConverterStation " + vscConv.getId());
+        boolean isPmode = EchUtil.isPMode(vscConv, hline);
+        Esg8charName znamsvc = new Esg8charName(dictionary.getEsgId(vscConv.getId())); // converter station ID
+        Esg8charName receivingNodeDcName = new Esg8charName("GROUND"); // receiving DC node name; always GROUND
+        Bus vscConvBus = EchUtil.getBus(vscConv.getTerminal(), config);
+        if (vscConvBus == null) {
+            throw new RuntimeException("VSCConverter " + vscConv.getId() + " not connected to a bus and not connectable");
+        }
+        Esg8charName acNode = dictionary.iidmIdExists(vscConvBus.getId()) ? new Esg8charName(dictionary.getEsgId(vscConvBus.getId()))
+                : null;
+        if (acNode == null) {
+            throw new RuntimeException("VSCConverter " + vscConv.getId() + " : acNode mapping not found");
+        }
+        EsgACDCVscConverter.ConverterState xstate = EsgACDCVscConverter.ConverterState.ON; // converter state ' ' ON; 'S' OFF
+        EsgACDCVscConverter.DCControlMode xregl = isPmode ? EsgACDCVscConverter.DCControlMode.AC_ACTIVE_POWER : EsgACDCVscConverter.DCControlMode.DC_VOLTAGE; // DC control mode 'P' AC_ACTIVE_POWER; 'V' DC_VOLTAGE
+        //AC control mode assumed to be "AC reactive power"(Q)
+        EsgACDCVscConverter.ACControlMode xoper = EsgACDCVscConverter.ACControlMode.AC_REACTIVE_POWER; // AC control mode 'V' AC_VOLTAGE; 'Q' AC_REACTIVE_POWER; 'A' AC_POWER_FACTOR
+        float rrdc = 0; // resistance [Ohms]
+        float rxdc = 16; // reactance [Ohms]
+
+        float activeSetPoint = zeroIfNanOrValue(hline.getActivePowerSetpoint()); // AC active power setpoint [MW]. Only if DC control mode is 'P'
+        //subtracts losses on the P side (even if the station in context is V)
+        float pac = activeSetPoint - Math.abs(activeSetPoint * EchUtil.getPStation(hline).getLossFactor() / 100.0f);
+        pac = isPmode ? pac : -pac; //change sign in case of V mode side
+        // multiplying  the line's nominalV by 2 corresponds to the fact that iIDM refers to the cable-ground voltage
+        // while Eurostag regulations to the cable-cable voltage
+        float pvd = EchUtil.getHvdcLineDcVoltage(hline); // DC voltage setpoint [MW]. Only if DC control mode is 'V'
+        float pre = -vscConv.getReactivePowerSetpoint(); // AC reactive power setpoint [Mvar]. Only if AC control mode is 'Q'
+        if ((Float.isNaN(pre)) || (vscConv.isVoltageRegulatorOn())) {
+            float terminalQ = vscConv.getTerminal().getQ();
+            if (Float.isNaN(terminalQ)) {
+                pre = zeroIfNanOrValue(pre);
+            } else {
+                pre = terminalQ;
+            }
+        }
+        float pco = Float.NaN; // AC power factor setpoint. Only if AC control mode is 'A'
+        float qvscsh = 1; // Reactive sharing cofficient [%]. Only if AC control mode is 'V'
+        float pvscmin = -hline.getMaxP(); // Minimum AC active power [MW]
+        float pvscmax = hline.getMaxP(); // Maximum AC active power [MW]
+        float qvscmin = vscConv.getReactiveLimits().getMinQ(0); // Minimum reactive power injected on AC node [kV]
+        float qvscmax = vscConv.getReactiveLimits().getMaxQ(0); // Maximum reactive power injected on AC node [kV]
+        // iIDM vscConv.getLossFactor() is in % of the MW. As it is, not suitable for vsb0, which is fixed in MW
+        // for now, set  vsb0, vsb1,vsb2 to 0
+        float vsb0 = 0; // Losses coefficient Beta0 [MW]
+        float vsb1 = 0; // Losses coefficient Beta1 [kW]
+        float vsb2 = 0; // Losses coefficient Beta2 [Ohms]
+
+        Bus connectedBus = vscConv.getTerminal().getBusBreakerView().getConnectableBus();
+        if (connectedBus == null) {
+            connectedBus = vscConv.getTerminal().getBusView().getConnectableBus();
+            if (connectedBus == null) {
+                throw new RuntimeException("VSCConverter " + vscConv.getId() + " : connected bus not found!");
+            }
+        }
+        float mvm = connectedBus.getV() / connectedBus.getVoltageLevel().getNominalV(); // Initial AC modulated voltage magnitude [p.u.]
+        float mva = connectedBus.getAngle(); // Initial AC modulated voltage angle [deg]
+        float pva = connectedBus.getV(); // AC voltage setpoint [kV]. Only if AC control mode is 'V'
+
+        return new EsgACDCVscConverter(
+                znamsvc,
+                vscConvDcName,
+                receivingNodeDcName,
+                acNode,
+                xstate,
+                xregl,
+                xoper,
+                rrdc,
+                rxdc,
+                pac,
+                pvd,
+                pva,
+                pre,
+                pco,
+                qvscsh,
+                pvscmin,
+                pvscmax,
+                qvscmin,
+                qvscmax,
+                vsb0,
+                vsb1,
+                vsb2,
+                mvm,
+                mva);
+    }
+
+    protected float computeLosses(HvdcLine hvdcLine, HvdcConverterStation convStation, float activeSetPoint) {
+        float cableLossesEnd = EchUtil.isPMode(convStation, hvdcLine) ? 0.0f : 1.0f;
+        float ploss = (float) (Math.abs(activeSetPoint * convStation.getLossFactor() / 100.0f) + cableLossesEnd * (hvdcLine.getR() - 0.25f) * Math.pow(activeSetPoint / hvdcLine.getNominalV(), 2)); //Eurostag model requires a fixed resistance of 1 ohm at 640 kV quivalent to 0.25 ohm at 320 kV
+        return ploss;
+    }
+
+    protected float computeLosses(HvdcLine hvdcLine, HvdcConverterStation convStation) {
+        float activeSetPoint = zeroIfNanOrValue(hvdcLine.getActivePowerSetpoint());
+        return computeLosses(hvdcLine, convStation, activeSetPoint);
+    }
+
+    private EsgLoad createConverterStationAdditionalLoad(HvdcLine hvdcLine, HvdcConverterStation convStation) {
+        float ploss = computeLosses(hvdcLine, convStation);
+        ConnectionBus rectConvBus = ConnectionBus.fromTerminal(convStation.getTerminal(), config, fakeNodes);
+        String fictionalLoadId = "fict_" + convStation.getId();
+        addToDictionary(fictionalLoadId, dictionary, EurostagNamingStrategy.NameType.LOAD);
+        return createLoad(rectConvBus, fictionalLoadId, ploss, 0);
+    }
+
+    private void createACDCVscConverters(EsgNetwork esgNetwork) {
+        //creates 2 DC nodes, for each hvdc line (one node per converter station)
+        for (HvdcLine hvdcLine : Identifiables.sort(network.getHvdcLines())) {
+            // skip lines with converter stations not in the main connected component
+            if (config.isExportMainCCOnly() && (!EchUtil.isInMainCc(hvdcLine.getConverterStation1(), config.isNoSwitch()) || !EchUtil.isInMainCc(hvdcLine.getConverterStation2(), config.isNoSwitch()))) {
+                LOGGER.warn("skipped HVDC line {}: at least one converter station is not in main component", hvdcLine.getId());
+                continue;
+            }
+            HvdcConverterStation convStation1 = hvdcLine.getConverterStation1();
+            HvdcConverterStation convStation2 = hvdcLine.getConverterStation2();
+
+            //create two dc nodes, one for each conv. station
+            Esg8charName hvdcNodeName1 = new Esg8charName(addToDictionary("DC_" + convStation1.getId(), dictionary, EurostagNamingStrategy.NameType.NODE));
+            Esg8charName hvdcNodeName2 = new Esg8charName(addToDictionary("DC_" + convStation2.getId(), dictionary, EurostagNamingStrategy.NameType.NODE));
+            float dcVoltage = EchUtil.getHvdcLineDcVoltage(hvdcLine);
+            esgNetwork.addDCNode(new EsgDCNode(new Esg2charName("DC"), hvdcNodeName1, dcVoltage, 1));
+            esgNetwork.addDCNode(new EsgDCNode(new Esg2charName("DC"), hvdcNodeName2, dcVoltage, 1));
+
+            //create a dc link, representing the hvdc line
+            //Eurostag model requires a resistance of 1 ohm (not hvdcLine.getR())
+            float r = 1.0f;
+            esgNetwork.addDCLink(new EsgDCLink(hvdcNodeName1, hvdcNodeName2, '1', r, EsgDCLink.LinkStatus.ON));
+
+            //create the two converter stations
+            EsgACDCVscConverter esgConv1 = createACDCVscConverter(network.getVscConverterStation(convStation1.getId()), hvdcLine, hvdcNodeName1);
+            EsgACDCVscConverter esgConv2 = createACDCVscConverter(network.getVscConverterStation(convStation2.getId()), hvdcLine, hvdcNodeName2);
+            esgNetwork.addACDCVscConverter(esgConv1);
+            esgNetwork.addACDCVscConverter(esgConv2);
+
+            //Create one load on the node to which converters stations are connected
+            esgNetwork.addLoad(createConverterStationAdditionalLoad(hvdcLine, convStation1));
+            esgNetwork.addLoad(createConverterStationAdditionalLoad(hvdcLine, convStation2));
+        }
+    }
+
+    @Override
     public EsgNetwork createNetwork(EsgGeneralParameters parameters) {
 
         EsgNetwork esgNetwork = new EsgNetwork();
@@ -605,6 +886,9 @@ public EsgNetwork createNetwork(EsgGeneralParameters parameters) {
         // static VAR compensators
         createStaticVarCompensators(esgNetwork);
 
+        // ACDC VSC Converters
+        createACDCVscConverters(esgNetwork);
+
         // nodes
         createNodes(esgNetwork);
 
diff --git a/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExporter.java b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExporter.java
new file mode 100644
index 00000000..c7024429
--- /dev/null
+++ b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExporter.java
@@ -0,0 +1,23 @@
+/**
+ * Copyright (c) 2017, RTE (http://www.rte-france.com)
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+package eu.itesla_project.iidm.eurostag.export;
+
+import eu.itesla_project.eurostag.network.EsgGeneralParameters;
+import eu.itesla_project.eurostag.network.EsgNetwork;
+import eu.itesla_project.eurostag.network.EsgSpecialParameters;
+
+import java.io.IOException;
+import java.nio.file.Path;
+
+/**
+ * @author Christian Biasuzzi <christian.biasuzzi@techrain.it>
+ */
+public interface EurostagEchExporter {
+    EsgNetwork createNetwork(EsgGeneralParameters parameters);
+
+    void write(Path file, EsgGeneralParameters parameters, EsgSpecialParameters specialParameters) throws IOException;
+}
diff --git a/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExporterFactory.java b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExporterFactory.java
new file mode 100644
index 00000000..732eb330
--- /dev/null
+++ b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExporterFactory.java
@@ -0,0 +1,16 @@
+/**
+ * Copyright (c) 2017, RTE (http://www.rte-france.com)
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+package eu.itesla_project.iidm.eurostag.export;
+
+import com.powsybl.iidm.network.Network;
+
+/**
+ * @author Christian Biasuzzi <christian.biasuzzi@techrain.it>
+ */
+public interface EurostagEchExporterFactory {
+    EurostagEchExporter createEchExporter(Network network, EurostagEchExportConfig exportConfig, BranchParallelIndexes parallelIndexes, EurostagDictionary dictionary, EurostagFakeNodes fakeNodes);
+}
diff --git a/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExporterFactoryImpl.java b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExporterFactoryImpl.java
new file mode 100644
index 00000000..967a5e4a
--- /dev/null
+++ b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExporterFactoryImpl.java
@@ -0,0 +1,20 @@
+/**
+ * Copyright (c) 2017, RTE (http://www.rte-france.com)
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+package eu.itesla_project.iidm.eurostag.export;
+
+import com.powsybl.iidm.network.Network;
+
+/**
+ * @author Christian Biasuzzi <christian.biasuzzi@techrain.it>
+ */
+public class EurostagEchExporterFactoryImpl implements EurostagEchExporterFactory {
+
+    @Override
+    public EurostagEchExporter createEchExporter(Network network, EurostagEchExportConfig exportConfig, BranchParallelIndexes parallelIndexes, EurostagDictionary dictionary, EurostagFakeNodes fakeNodes) {
+        return new EurostagEchExport(network, exportConfig, parallelIndexes, dictionary, fakeNodes);
+    }
+}
diff --git a/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagNamingStrategy.java b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagNamingStrategy.java
index 5ed3a393..579a82c0 100644
--- a/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagNamingStrategy.java
+++ b/eurostag-ech-export/src/main/java/eu/itesla_project/iidm/eurostag/export/EurostagNamingStrategy.java
@@ -20,7 +20,8 @@ enum NameType {
         GENERATOR(8),
         LOAD(8),
         BANK(8),
-        SVC(8);
+        SVC(8),
+        VSC(8);
 
         int length;
 
diff --git a/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/CheckEurostagEchExportConfigTest.java b/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/CheckEurostagEchExporterConfigTest.java
similarity index 77%
rename from eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/CheckEurostagEchExportConfigTest.java
rename to eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/CheckEurostagEchExporterConfigTest.java
index 1ab2f2b7..795d69ef 100644
--- a/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/CheckEurostagEchExportConfigTest.java
+++ b/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/CheckEurostagEchExporterConfigTest.java
@@ -22,7 +22,7 @@
 /**
  * @author Christian Biasuzzi <christian.biasuzzi@techrain.it>
  */
-public class CheckEurostagEchExportConfigTest {
+public class CheckEurostagEchExporterConfigTest {
 
     InMemoryPlatformConfig platformConfig;
     FileSystem fileSystem;
@@ -39,10 +39,11 @@ public void tearDown() throws Exception {
         fileSystem.close();
     }
 
-    private EurostagEchExportConfig getConfigFromFile(FileSystem fileSystem, boolean specificCompatibility) {
+    private EurostagEchExportConfig getConfigFromFile(FileSystem fileSystem, boolean specificCompatibility, boolean mainCcOnly) {
         InMemoryPlatformConfig platformConfig = new InMemoryPlatformConfig(fileSystem);
         MapModuleConfig moduleConfig = platformConfig.createModuleConfig("eurostag-ech-export");
         moduleConfig.setStringProperty("svcAsFixedInjectionInLF", "false");
+        moduleConfig.setStringProperty("exportMainCCOnly", Boolean.toString(mainCcOnly));
 
         moduleConfig = platformConfig.createModuleConfig("load-flow-default-parameters");
         moduleConfig.setStringProperty("specificCompatibility", Boolean.toString(specificCompatibility));
@@ -59,15 +60,26 @@ public void testConfig() throws IOException {
 
     @Test
     public void testConfigFromFile() throws IOException {
-        EurostagEchExportConfig config = getConfigFromFile(fileSystem, false);
+        EurostagEchExportConfig config = getConfigFromFile(fileSystem, false, false);
         assertEquals(false, config.isSvcAsFixedInjectionInLF());
     }
 
     @Test
     public void testConfigSpecificCompatibility() throws IOException {
-        EurostagEchExportConfig config = getConfigFromFile(fileSystem, true);
+        EurostagEchExportConfig config = getConfigFromFile(fileSystem, true, false);
         assertEquals(true, config.isSvcAsFixedInjectionInLF());
     }
 
+    @Test
+    public void testConfigExportNoMainCC() throws IOException {
+        EurostagEchExportConfig config = getConfigFromFile(fileSystem, true, false);
+        assertEquals(false, config.isExportMainCCOnly());
+    }
+
+    @Test
+    public void testConfigExportMainCC() throws IOException {
+        EurostagEchExportConfig config = getConfigFromFile(fileSystem, true, true);
+        assertEquals(true, config.isExportMainCCOnly());
+    }
 
 }
diff --git a/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/EchUtilsTest.java b/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/EchUtilsTest.java
new file mode 100644
index 00000000..adb48431
--- /dev/null
+++ b/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/EchUtilsTest.java
@@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2018, RTE (http://www.rte-france.com)
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+package eu.itesla_project.iidm.eurostag.export;
+
+import com.google.common.collect.Lists;
+import com.google.common.jimfs.Configuration;
+import com.google.common.jimfs.Jimfs;
+import com.powsybl.commons.config.InMemoryPlatformConfig;
+import com.powsybl.commons.config.MapModuleConfig;
+import com.powsybl.iidm.network.HvdcLine;
+import com.powsybl.iidm.network.Network;
+import com.powsybl.iidm.network.VscConverterStation;
+import com.powsybl.iidm.network.test.EurostagTutorialExample1Factory;
+import com.powsybl.iidm.network.test.HvdcTestNetwork;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.nio.file.FileSystem;
+
+import static org.junit.Assert.*;
+
+
+/**
+ * @author Christian Biasuzzi <christian.biasuzzi@techrain.it>
+ */
+public class EchUtilsTest {
+
+
+    private final float delta = 0.0f;
+    private Network network;
+    private Network networkHvdc;
+
+    @Before
+    public void setUp() throws Exception {
+        network = EurostagTutorialExample1Factory.create();
+        networkHvdc = HvdcTestNetwork.createVsc();
+    }
+
+    private EurostagEchExportConfig getConfig(boolean noSwitch, boolean exportMainCCOnly) {
+        FileSystem fileSystem = Jimfs.newFileSystem(Configuration.unix());
+        InMemoryPlatformConfig platformConfig = new InMemoryPlatformConfig(fileSystem);
+        MapModuleConfig moduleConfig = platformConfig.createModuleConfig("eurostag-ech-export");
+        moduleConfig.setStringProperty("noSwitch", Boolean.toString(noSwitch));
+        moduleConfig.setStringProperty("exportMainCCOnly", Boolean.toString(exportMainCCOnly));
+        return EurostagEchExportConfig.load(platformConfig);
+    }
+
+    private EurostagEchExportConfig getConfig(boolean noSwitch) {
+        return getConfig(noSwitch, false);
+    }
+
+    @Test
+    public void testGetHvdcLineDcVoltage() {
+        networkHvdc.getHvdcLineStream().forEach(line -> assertEquals(line.getNominalV() * 2.0f, EchUtil.getHvdcLineDcVoltage(line), delta));
+    }
+
+    @Test
+    public void testGetHvdcLineDcVoltageNull() {
+        try {
+            EchUtil.getHvdcLineDcVoltage(null);
+            fail("Expected not null parameter");
+        } catch (NullPointerException e) {
+        }
+
+    }
+
+    @Test
+    public void testIsImMainCcBus() {
+        Lists.newArrayList(true, false).stream().forEach(exportMainCCOnly -> {
+            EchUtil.getBuses(networkHvdc, getConfig(false, exportMainCCOnly)).forEach(bus -> {
+                assertEquals(EchUtil.isInMainCc(bus), true);
+            });
+        });
+    }
+
+    @Test
+    public void testIsImMainCcGen() {
+        Lists.newArrayList(true, false).stream().forEach(exportMainCCOnly -> {
+            network.getGeneratorStream().forEach(gen -> {
+                assertEquals(EchUtil.isInMainCc(gen, exportMainCCOnly), true);
+            });
+        });
+    }
+
+    @Test
+    public void testIsImMainCcLine() {
+        Lists.newArrayList(true, false).stream().forEach(exportMainCCOnly -> {
+            network.getLines().forEach(line -> {
+                assertEquals(EchUtil.isInMainCc(line, exportMainCCOnly), true);
+            });
+        });
+    }
+
+    @Test
+    public void testIsPmode() throws IOException {
+        HvdcLine hline = networkHvdc.getHvdcLine("L");
+        assertTrue(EchUtil.isPMode(networkHvdc.getVscConverterStation("C2"), hline));
+        assertFalse(EchUtil.isPMode(networkHvdc.getVscConverterStation("C1"), hline));
+    }
+
+    @Test
+    public void testGetPVstation() throws IOException {
+        HvdcLine hline = networkHvdc.getHvdcLine("L");
+        assertTrue(EchUtil.getPStation(hline).getId().equals(networkHvdc.getVscConverterStation("C2").getId()));
+        assertTrue(EchUtil.getVStation(hline).getId().equals(networkHvdc.getVscConverterStation("C1").getId()));
+    }
+
+}
\ No newline at end of file
diff --git a/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExportTest.java b/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExportTest.java
index c3d2ea0d..6655bcda 100644
--- a/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExportTest.java
+++ b/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/EurostagEchExportTest.java
@@ -7,11 +7,12 @@
 package eu.itesla_project.iidm.eurostag.export;
 
 import com.google.common.io.CharStreams;
-import eu.itesla_project.eurostag.network.EsgGeneralParameters;
-import eu.itesla_project.eurostag.network.EsgSpecialParameters;
-import com.powsybl.iidm.network.Network;
+import com.powsybl.iidm.network.*;
 import com.powsybl.iidm.network.test.EurostagTutorialExample1Factory;
+import com.powsybl.iidm.network.test.HvdcTestNetwork;
 import com.powsybl.iidm.network.test.SvcTestCaseFactory;
+import eu.itesla_project.eurostag.network.EsgGeneralParameters;
+import eu.itesla_project.eurostag.network.EsgSpecialParameters;
 import org.joda.time.LocalDate;
 import org.junit.Test;
 
@@ -27,15 +28,20 @@
  */
 public class EurostagEchExportTest {
 
-    private void test(Network network, String reference, LocalDate editDate, EsgSpecialParameters specialParameters) throws IOException {
+    private void test(Network network, String reference, LocalDate editDate, EsgSpecialParameters specialParameters, EurostagEchExportConfig config) throws IOException {
         StringWriter writer = new StringWriter();
         EsgGeneralParameters parameters = new EsgGeneralParameters();
         parameters.setEditDate(editDate);
-        new EurostagEchExport(network).write(writer, parameters, specialParameters);
+        new EurostagEchExport(network, config).write(writer, parameters, specialParameters);
         writer.close();
         assertEquals(CharStreams.toString(new InputStreamReader(getClass().getResourceAsStream(reference), StandardCharsets.UTF_8)), writer.toString());
     }
 
+    private void test(Network network, String reference, LocalDate editDate, EsgSpecialParameters specialParameters) throws IOException {
+        test(network, reference, editDate, specialParameters, new EurostagEchExportConfig());
+    }
+
+
     @Test
     public void test() throws IOException {
         Network network = EurostagTutorialExample1Factory.create();
@@ -55,4 +61,123 @@ public void testSVC() throws IOException {
         EsgSpecialParameters specialParameters = new EsgSpecialParameters();
         test(network, "/eurostag-svc-test.ech", LocalDate.parse("2016-01-01"), specialParameters);
     }
+
+    @Test
+    public void testHVDC() throws IOException {
+        Network network = HvdcTestNetwork.createVsc();
+        network.getVoltageLevelStream().findFirst().orElse(null)
+                .newGenerator().setId("G1")
+                .setConnectableBus("B1")
+                .setBus("B1")
+                .setVoltageRegulatorOn(true)
+                .setTargetP(100.0F)
+                .setTargetV(400.0F)
+                .setMinP(50.0F)
+                .setMaxP(150.0F)
+                .add();
+        EsgSpecialParameters specialParameters = new EsgSpecialParameters();
+        test(network, "/eurostag-hvdc-test.ech", LocalDate.parse("2016-01-01"), specialParameters);
+    }
+
+    private void addLine(Network network, VoltageLevel vlhv1, VoltageLevel vlhv2, String idLine, float g1, float g2, float b1, float b2) {
+        Bus nhv1 = vlhv1.getBusBreakerView().newBus()
+                .setId("N1" + idLine)
+                .add();
+        Bus nhv2 = vlhv2.getBusBreakerView().newBus()
+                .setId("N2" + idLine)
+                .add();
+        network.newLine()
+                .setId(idLine)
+                .setVoltageLevel1(vlhv1.getId())
+                .setBus1(nhv1.getId())
+                .setConnectableBus1(nhv1.getId())
+                .setVoltageLevel2(vlhv2.getId())
+                .setBus2(nhv2.getId())
+                .setConnectableBus2(nhv2.getId())
+                .setR(3)
+                .setX(33)
+                .setG1(g1)
+                .setB1(b1)
+                .setG2(g2)
+                .setB2(b2)
+                .add();
+    }
+
+    @Test
+    public void testLines() throws IOException {
+        Network network = EurostagTutorialExample1Factory.create();
+        VoltageLevel vlhv1 = network.getSubstation("P1").newVoltageLevel()
+                .setId("VL1")
+                .setNominalV(380)
+                .setTopologyKind(TopologyKind.BUS_BREAKER)
+                .add();
+        VoltageLevel vlhv2 = network.getSubstation("P2").newVoltageLevel()
+                .setId("VL2")
+                .setNominalV(380)
+                .setTopologyKind(TopologyKind.BUS_BREAKER)
+                .add();
+
+        float bTest1 = EurostagEchExport.B_EPSILON * 2f;
+
+        //G and B are the same on each side, G are 0
+        addLine(network, vlhv1, vlhv2, "L1", 0f, 0f, 0f, 0f);
+        addLine(network, vlhv1, vlhv2, "L2", 0f, 0f, bTest1, bTest1);
+        //B are not the same, G are 0
+        addLine(network, vlhv1, vlhv2, "L3", 0f, 0f, bTest1, 0); // dummy shunt expected in the .ech
+        addLine(network, vlhv1, vlhv2, "L4", 0f, 0f, 0, bTest1); // dummy shunt expected in the .ech
+        addLine(network, vlhv1, vlhv2, "L5", 0f, 0f, EurostagEchExport.B_EPSILON / 2f, 0);
+        addLine(network, vlhv1, vlhv2, "L6", 0f, 0f, 0, EurostagEchExport.B_EPSILON / 2f);
+        //B are not the same, G are not 0
+        addLine(network, vlhv1, vlhv2, "L7", 1f, 0f, bTest1, 0);
+        addLine(network, vlhv1, vlhv2, "L8", 0f, 1f, bTest1, 0);
+
+        EsgSpecialParameters specialParameters = new EsgSpecialParameters();
+        test(network, "/eurostag-tutorial-example1_lines.ech", LocalDate.parse("2016-03-01"), specialParameters);
+    }
+
+
+    @Test
+    public void testCptRpt() throws IOException {
+        Network network = EurostagTutorialExample1Factory.create();
+        TwoWindingsTransformer nhv2Nload = network.getTwoWindingsTransformer("NHV2_NLOAD");
+
+        //adds a phase tap changer to the NHV2_NLOAD TwoWindingTransformer (it has already a ratio tap changer)
+        //so that both tap changers adjust rho
+        nhv2Nload.newPhaseTapChanger()
+                .setTapPosition(0)
+                .setRegulationTerminal(nhv2Nload.getTerminal2())
+                .setRegulationMode(PhaseTapChanger.RegulationMode.FIXED_TAP)
+                .setRegulationValue(200)
+                .beginStep()
+                .setAlpha(-20f)
+                .setRho(0.96f)
+                .setR(0f)
+                .setX(0f)
+                .setG(0f)
+                .setB(0f)
+                .endStep()
+                .add();
+
+        EsgSpecialParameters specialParameters = new EsgSpecialParameters();
+        test(network, "/eurostag-tutorial-example1_cptrpt.ech", LocalDate.parse("2016-03-01"), specialParameters);
+    }
+
+    @Test
+    public void testVoltageRegulationException() throws IOException {
+        Network network = EurostagTutorialExample1Factory.create();
+
+        //voltage regulator exception:  if specificCompatibility && (g.getTargetP() < 0.0001) && (g.getMinP() > 0.0001)
+        // turn off g's voltage regulation
+        Generator g = network.getGenerator("GEN");
+        g.setMinP(300f);
+        g.setTargetP(0);
+
+        EsgSpecialParameters specialParameters = new EsgSpecialParameters();
+        EurostagEchExportConfig exTemp = new EurostagEchExportConfig();
+        EurostagEchExportConfig exportConfig= new EurostagEchExportConfig(exTemp.isNoGeneratorMinMaxQ(), exTemp.isNoSwitch(), exTemp.getForbiddenCharactersString(),
+                exTemp.getForbiddenCharactersReplacement(), exTemp.isSvcAsFixedInjectionInLF(), true, exTemp.isExportMainCCOnly());
+
+        test(network, "/eurostag-tutorial-example1_vre.ech", LocalDate.parse("2016-03-01"), specialParameters, exportConfig);
+    }
+
 }
\ No newline at end of file
diff --git a/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/EurostagNamingStrategyTest.java b/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/EurostagNamingStrategyTest.java
index 71bb5535..c0554b3f 100644
--- a/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/EurostagNamingStrategyTest.java
+++ b/eurostag-ech-export/src/test/java/eu/itesla_project/iidm/eurostag/export/EurostagNamingStrategyTest.java
@@ -63,6 +63,13 @@ private Network createMockNetwork(List<String> genNames) {
                 .thenReturn(Collections.emptyList());
         Mockito.when(net.getThreeWindingsTransformers())
                 .thenReturn(Collections.emptyList());
+        Mockito.when(net.getVscConverterStations())
+                .thenReturn(Collections.emptyList());
+        Mockito.when(net.getHvdcLines())
+                .thenReturn(Collections.emptyList());
+        Mockito.when(net.getHvdcConverterStations())
+                .thenReturn(Collections.emptyList());
+
 
         List<Generator> genList = genNames.stream().map(x -> {
             Generator g = Mockito.mock(Generator.class);
diff --git a/eurostag-ech-export/src/test/resources/eurostag-hvdc-test.ech b/eurostag-ech-export/src/test/resources/eurostag-hvdc-test.ech
new file mode 100644
index 00000000..6145c9e4
--- /dev/null
+++ b/eurostag-ech-export/src/test/resources/eurostag-hvdc-test.ech
@@ -0,0 +1,44 @@
+HEADER     01/01/16 5.1     
+
+B
+
+9 1 0 0 1 1 20    0.005                                 4             100. 1 1
+
+SP INPVPQ            2
+SP THMAX     0.100000 
+SP EMAXF     0.100000 
+SP ZMIN      0.000200 
+SP RAMIN     0.800000 
+SP RAMAX     1.200000 
+SP TOLPLO    0.001000 
+
+GC hvdctest/InitialState                                                        
+
+AA FA               
+AA FR               
+DA DC               
+
+1FAFAKENOD1                                                                             380.            1.       0.       0.       0.
+1FAFAKENOD2                                                                             380.            1.       0.       0.       0.
+1FRB1                                                                                   400.            1.       0.       0.       0.
+5  B1                                        0.
+1FRVL2_0                                                                                400.            1.       0.       0.       0.
+1FRVL2_1                                                                                400.            1.       0.       0.       0.
+
+6 VL2_0    VL2_1   1                                                    0.       0.
+
+CH fict_C1  Y B1             0.       0.   0.3983       0.       0.       0.       0.       0.
+CH fict_C2  Y VL2_1          0.       0.   0.0308       0.       0.       0.       0.       0.
+
+G  G1       Y B1            50.     100.     150. -2147483          21474836 V     400. B1             1.       0.       0.
+
+DC N DC_C1    DC     800.       1.
+DC N DC_C2    DC     800.       1.
+
+DC L DC_C1    DC_C2    1       1.  
+
+DC V C1       DC_C1    GROUND   B1         V Q       0.      16. -279.969     800.               50.                1.
+DC V    -300.     300.       0.      10.       0.       0.       0.                  
+DC V C2       DC_C2    GROUND   VL2_1      P Q       0.      16. 279.9692     800.             -123.                1.
+DC V    -300.     300.       0.      10.       0.       0.       0.                  
+
diff --git a/eurostag-ech-export/src/test/resources/eurostag-tutorial-example1_cptrpt.ech b/eurostag-ech-export/src/test/resources/eurostag-tutorial-example1_cptrpt.ech
new file mode 100644
index 00000000..bb8344ec
--- /dev/null
+++ b/eurostag-ech-export/src/test/resources/eurostag-tutorial-example1_cptrpt.ech
@@ -0,0 +1,43 @@
+HEADER     01/03/16 5.1     
+
+B
+
+9 1 0 0 1 1 20    0.005                                 4             100. 1 1
+
+SP INPVPQ            2
+SP THMAX     0.100000 
+SP EMAXF     0.100000 
+SP ZMIN      0.000200 
+SP RAMIN     0.800000 
+SP RAMAX     1.200000 
+SP TOLPLO    0.001000 
+
+GC sim1/InitialState                                                            
+
+AA FA               
+AA FR               
+
+1FAFAKENOD1                                                                             380.            1.       0.       0.       0.
+1FAFAKENOD2                                                                             380.            1.       0.       0.       0.
+1FRNGEN                                                                                  24.            1.       0.       0.       0.
+5  NGEN                                      0.
+1FRNHV1                                                                                 380.            1.       0.       0.       0.
+1FRNHV2                                                                                 380.            1.       0.       0.       0.
+1FRNLOAD                                                                                150.            1.       0.       0.       0.
+
+3 NHV1     NHV2    1 0.002078 0.022853       0. 0.278692     100.       0.       0.
+3 NHV1     NHV2    2 0.002078 0.022853       0. 0.278692     100.       0.       0.
+
+48NGEN     NHV1    1     100.0.018462       0.       0.       1.       0.       0.
+48                      1    1                                     N
+48                      1     22.8     380. 0.769231       0.
+48NHV2     NLOAD   1     100.   0.021       0.       0.       1.       0.       0.
+48                      2    2 NLOAD        158.                   V
+48                      1  465.066     150.      1.8       0.
+48                      2 395.3061     150.      1.8       0.
+48                      3 343.7444     150.      1.8       0.
+
+CH LOAD     Y NLOAD          0.       0.     600.       0.       0.     200.       0.       0.
+
+G  GEN      Y NGEN     -9999.99     607.  9999.99 -9999.99     301.  9999.99 V     24.5 NGEN           1.       0.       0.
+
diff --git a/eurostag-ech-export/src/test/resources/eurostag-tutorial-example1_lines.ech b/eurostag-ech-export/src/test/resources/eurostag-tutorial-example1_lines.ech
new file mode 100644
index 00000000..db9097b7
--- /dev/null
+++ b/eurostag-ech-export/src/test/resources/eurostag-tutorial-example1_lines.ech
@@ -0,0 +1,73 @@
+HEADER     01/03/16 5.1     
+
+B
+
+9 1 0 0 1 1 20    0.005                                 4             100. 1 1
+
+SP INPVPQ            2
+SP THMAX     0.100000 
+SP EMAXF     0.100000 
+SP ZMIN      0.000200 
+SP RAMIN     0.800000 
+SP RAMAX     1.200000 
+SP TOLPLO    0.001000 
+
+GC sim1/InitialState                                                            
+
+AA FA               
+AA FR               
+
+1FAFAKENOD1                                                                             380.            1.       0.       0.       0.
+1FAFAKENOD2                                                                             380.            1.       0.       0.       0.
+1FRN1L1                                                                                 380.            1.       0.       0.       0.
+1FRN1L2                                                                                 380.            1.       0.       0.       0.
+1FRN1L3                                                                                 380.            1.       0.       0.       0.
+1FRN1L4                                                                                 380.            1.       0.       0.       0.
+1FRN1L5                                                                                 380.            1.       0.       0.       0.
+1FRN1L6                                                                                 380.            1.       0.       0.       0.
+1FRN1L7                                                                                 380.            1.       0.       0.       0.
+1FRN1L8                                                                                 380.            1.       0.       0.       0.
+1FRN2L1                                                                                 380.            1.       0.       0.       0.
+1FRN2L2                                                                                 380.            1.       0.       0.       0.
+1FRN2L3                                                                                 380.            1.       0.       0.       0.
+1FRN2L4                                                                                 380.            1.       0.       0.       0.
+1FRN2L5                                                                                 380.            1.       0.       0.       0.
+1FRN2L6                                                                                 380.            1.       0.       0.       0.
+1FRN2L7                                                                                 380.            1.       0.       0.       0.
+1FRN2L8                                                                                 380.            1.       0.       0.       0.
+1FRNGEN                                                                                  24.            1.       0.       0.       0.
+5  NGEN                                      0.
+1FRNHV1                                                                                 380.            1.       0.       0.       0.
+1FRNHV2                                                                                 380.            1.       0.       0.       0.
+1FRNLOAD                                                                                150.            1.       0.       0.       0.
+
+3 N1L1     N2L1    1 0.002078 0.022853       0.       0.     100.       0.       0.
+3 N1L2     N2L2    1 0.002078 0.022853       0. 0.002888     100.       0.       0.
+3 N1L3     N2L3    1 0.002078 0.022853       0.       0.     100.       0.       0.
+3 N1L4     N2L4    1 0.002078 0.022853       0.       0.     100.       0.       0.
+3 N1L5     N2L5    1 0.002078 0.022853       0. 0.000361     100.       0.       0.
+3 N1L6     N2L6    1 0.002078 0.022853       0. 0.000361     100.       0.       0.
+3 NHV1     NHV2    1 0.002078 0.022853       0. 0.278692     100.       0.       0.
+3 NHV1     NHV2    2 0.002078 0.022853       0. 0.278692     100.       0.       0.
+
+P N1L7     N2L7    1 0.002078 0.022853    1444. 0.002888     100.
+P                    0.002078 0.022853       0.       0.
+P N1L8     N2L8    1 0.002078 0.022853       0. 0.002888     100.
+P                    0.002078 0.022853    1444.       0.
+
+48NGEN     NHV1    1     100.0.018462       0.       0.       1.       0.       0.
+48                      1    1                                     N
+48                      1     22.8     380. 0.769231       0.
+48NHV2     NLOAD   1     100.   0.021       0.       0.       1.       0.       0.
+48                      2    2 NLOAD        158.                   V
+48                      1 446.4633     150.      1.8       0.
+48                      2 379.4938     150.      1.8       0.
+48                      3 329.9946     150.      1.8       0.
+
+CH LOAD     Y NLOAD          0.       0.     600.       0.       0.     200.       0.       0.
+
+G  GEN      Y NGEN     -9999.99     607.  9999.99 -9999.99     301.  9999.99 V     24.5 NGEN           1.       0.       0.
+
+C FKSHL3   N1L3                         1       0.   0.2888   1 N       0.                0.       0.         
+C FKSHL4   N2L4                         1       0.   0.2888   1 N       0.                0.       0.         
+
diff --git a/eurostag-ech-export/src/test/resources/eurostag-tutorial-example1_vre.ech b/eurostag-ech-export/src/test/resources/eurostag-tutorial-example1_vre.ech
new file mode 100644
index 00000000..72873323
--- /dev/null
+++ b/eurostag-ech-export/src/test/resources/eurostag-tutorial-example1_vre.ech
@@ -0,0 +1,43 @@
+HEADER     01/03/16 5.1     
+
+B
+
+9 1 0 0 1 1 20    0.005                                 4             100. 1 1
+
+SP INPVPQ            2
+SP THMAX     0.100000 
+SP EMAXF     0.100000 
+SP ZMIN      0.000200 
+SP RAMIN     0.800000 
+SP RAMAX     1.200000 
+SP TOLPLO    0.001000 
+
+GC sim1/InitialState                                                            
+
+AA FA               
+AA FR               
+
+1FAFAKENOD1                                                                             380.            1.       0.       0.       0.
+1FAFAKENOD2                                                                             380.            1.       0.       0.       0.
+1FRNGEN                                                                                  24.            1.       0.       0.       0.
+5  NGEN                                      0.
+1FRNHV1                                                                                 380.            1.       0.       0.       0.
+1FRNHV2                                                                                 380.            1.       0.       0.       0.
+1FRNLOAD                                                                                150.            1.       0.       0.       0.
+
+3 NHV1     NHV2    1 0.002078 0.022853       0. 0.278692     100.       0.       0.
+3 NHV1     NHV2    2 0.002078 0.022853       0. 0.278692     100.       0.       0.
+
+48NGEN     NHV1    1     100.0.018462       0.       0.       1.       0.       0.
+48                      1    1                                     N
+48                      1     22.8     380. 0.769231       0.
+48NHV2     NLOAD   1     100.   0.021       0.       0.       1.       0.       0.
+48                      2    2 NLOAD        158.                   V
+48                      1 446.4633     150.      1.8       0.
+48                      2 379.4938     150.      1.8       0.
+48                      3 329.9946     150.      1.8       0.
+
+CH LOAD     Y NLOAD          0.       0.     600.       0.       0.     200.       0.       0.
+
+G  GEN      Y NGEN         300.       0.  9999.99 -9999.99     301.  9999.99 N          NGEN           1.       0.       0.
+
diff --git a/eurostag-integration/src/main/java/eu/itesla_project/eurostag/EurostagExportTool.java b/eurostag-integration/src/main/java/eu/itesla_project/eurostag/EurostagExportTool.java
index ef9e9307..24c85a5d 100644
--- a/eurostag-integration/src/main/java/eu/itesla_project/eurostag/EurostagExportTool.java
+++ b/eurostag-integration/src/main/java/eu/itesla_project/eurostag/EurostagExportTool.java
@@ -88,7 +88,9 @@ public void run(CommandLine line, ToolRunningContext context) throws Exception {
             } else {
                 parameters.setStartMode(eurostagConfig.isLfWarmStart() ? EsgGeneralParameters.StartMode.WARM_START : EsgGeneralParameters.StartMode.FLAT_START);
             }
-            EsgNetwork networkEch = new EurostagEchExport(network, exportConfig, parallelIndexes, dictionary, fakeNodes).createNetwork(parameters);
+
+            EurostagEchExporterFactory echExportFactory = defaultConfig.newFactoryImpl(EurostagEchExporterFactory.class, EurostagEchExporterFactoryImpl.class);
+            EsgNetwork networkEch = echExportFactory.createEchExporter(network, exportConfig, parallelIndexes, dictionary, fakeNodes).createNetwork(parameters);
             new EurostagNetworkModifier().hvLoadModelling(networkEch);
             new EsgWriter(networkEch, parameters, specialParameters).write(writer, network.getId() + "/" + network.getStateManager().getWorkingStateId());
         }
@@ -111,7 +113,7 @@ public void run(CommandLine line, ToolRunningContext context) throws Exception {
 
         // export limits
         try (OutputStream os = Files.newOutputStream(outputDir.resolve(LIMITS_ZIP_FILE_NAME))) {
-            EurostagImpactAnalysis.writeLimits(network, dictionary, os);
+            EurostagImpactAnalysis.writeLimits(network, dictionary, os, exportConfig);
         }
     }
 
diff --git a/eurostag-integration/src/main/java/eu/itesla_project/eurostag/EurostagImpactAnalysis.java b/eurostag-integration/src/main/java/eu/itesla_project/eurostag/EurostagImpactAnalysis.java
index 33fb0802..52b74460 100644
--- a/eurostag-integration/src/main/java/eu/itesla_project/eurostag/EurostagImpactAnalysis.java
+++ b/eurostag-integration/src/main/java/eu/itesla_project/eurostag/EurostagImpactAnalysis.java
@@ -25,6 +25,7 @@
 import com.powsybl.simulation.*;
 import com.powsybl.simulation.securityindexes.SecurityIndex;
 import com.powsybl.simulation.securityindexes.SecurityIndexParser;
+import eu.itesla_project.iidm.eurostag.export.EurostagEchExportConfig;
 import org.apache.commons.configuration.ConfigurationException;
 import org.apache.commons.configuration.HierarchicalINIConfiguration;
 import org.apache.commons.configuration.SubnodeConfiguration;
@@ -43,6 +44,7 @@
 import java.nio.file.Path;
 import java.util.*;
 import java.util.concurrent.CompletableFuture;
+import java.util.stream.Collectors;
 
 import static com.powsybl.computation.FilePostProcessor.FILE_GZIP;
 import static com.powsybl.computation.FilePreProcessor.ARCHIVE_UNZIP;
@@ -125,6 +127,8 @@ public class EurostagImpactAnalysis implements ImpactAnalysis, EurostagConstants
 
     private final EurostagConfig config;
 
+    private final EurostagEchExportConfig exportConfig;
+
     private final Command allCmd;
 
     private final List<Contingency> allContingencies = new ArrayList<>();
@@ -137,11 +141,11 @@ public class EurostagImpactAnalysis implements ImpactAnalysis, EurostagConstants
 
     public EurostagImpactAnalysis(Network network, ComputationManager computationManager, int priority,
                                   ContingenciesProvider contingenciesProvider) {
-        this(network, computationManager, priority, contingenciesProvider, EurostagConfig.load());
+        this(network, computationManager, priority, contingenciesProvider, EurostagConfig.load(), EurostagEchExportConfig.load());
     }
 
     public EurostagImpactAnalysis(Network network, ComputationManager computationManager, int priority,
-                                  ContingenciesProvider contingenciesProvider, EurostagConfig config) {
+                                  ContingenciesProvider contingenciesProvider, EurostagConfig config, EurostagEchExportConfig exportConfig) {
         Objects.requireNonNull(network, "network is null");
         Objects.requireNonNull(computationManager, "computation manager is null");
         Objects.requireNonNull(contingenciesProvider, "contingencies provider is null");
@@ -151,6 +155,7 @@ public EurostagImpactAnalysis(Network network, ComputationManager computationMan
         this.priority = priority;
         this.contingenciesProvider = contingenciesProvider;
         this.config = config;
+        this.exportConfig = exportConfig;
         allCmd = createCommand(ALL_SCENARIOS_ZIP_FILE_NAME, WP43_ALL_CONFIGS_ZIP_FILE_NAME);
         subsetCmd = createCommand(PARTIAL_SCENARIOS_ZIP_FILE_NAME, WP43_PARTIAL_CONFIGS_ZIP_FILE_NAME);
     }
@@ -202,11 +207,13 @@ public String getVersion() {
 
     //needed by wp43 integration
     //contains lines, only
-    private static void dumpLinesDictionary(Network network, EurostagDictionary dictionary, Path dir) throws IOException {
+    private static void dumpLinesDictionary(Network network, EurostagDictionary dictionary, Path dir, EurostagEchExportConfig exportConfig) throws IOException {
         try (BufferedWriter os = Files.newBufferedWriter(dir.resolve("dict_lines.csv"), StandardCharsets.UTF_8)) {
-            for (Identifiable obj : Identifiables.sort(Iterables.concat(network.getLines(),
-                    network.getTwoWindingsTransformers(),
-                    network.getDanglingLines()))) {
+            for (Identifiable obj : Identifiables.sort(Iterables.concat(
+                    network.getLineStream().filter(line -> !(exportConfig.isExportMainCCOnly() && !EchUtil.isInMainCc(line, exportConfig.isNoSwitch()))).collect(Collectors.toList()),
+                    network.getTwoWindingsTransformerStream().filter(twt -> !(exportConfig.isExportMainCCOnly() && !EchUtil.isInMainCc(twt, exportConfig.isNoSwitch()))).collect(Collectors.toList()),
+                    network.getDanglingLineStream().filter(dl -> !(exportConfig.isExportMainCCOnly() && !EchUtil.isInMainCc(dl, exportConfig.isNoSwitch()))).collect(Collectors.toList())
+            ))) {
                 os.write(obj.getId() + ";" + dictionary.getEsgId(obj.getId()));
                 os.newLine();
             }
@@ -218,11 +225,13 @@ private static void dumpLinesDictionary(Network network, EurostagDictionary dict
 
     //needed by wp43 integration
     //contains buses, only
-    private static void dumpBusesDictionary(Network network, EurostagDictionary dictionary, Path dir) throws IOException {
+    private static void dumpBusesDictionary(Network network, EurostagDictionary dictionary, Path dir, EurostagEchExportConfig exportConfig) throws IOException {
         try (BufferedWriter os = Files.newBufferedWriter(dir.resolve("dict_buses.csv"), StandardCharsets.UTF_8)) {
             for (Bus bus : Identifiables.sort(EchUtil.getBuses(network, dictionary.getConfig()))) {
-                os.write(bus.getId() + ";" + dictionary.getEsgId(bus.getId()));
-                os.newLine();
+                if (!(exportConfig.isExportMainCCOnly() && (!EchUtil.isInMainCc(bus)))) {
+                    os.write(bus.getId() + ";" + dictionary.getEsgId(bus.getId()));
+                    os.newLine();
+                }
             }
         }
     }
@@ -251,19 +260,28 @@ private static void dumpLimits(EurostagDictionary dictionary, BufferedWriter wri
         writer.newLine();
     }
 
-    private static void writeLimits(Network network, EurostagDictionary dictionary, Domain domain, OutputStream os) throws IOException {
+    protected static void writeLimits(Network network, EurostagDictionary dictionary, Domain domain, OutputStream os, EurostagEchExportConfig exportConfig) throws IOException {
         GenericArchive archive = domain.getArchiveFactory().create(GenericArchive.class);
         try (FileSystem fileSystem = ShrinkWrapFileSystems.newFileSystem(archive)) {
             Path rootDir = fileSystem.getPath("/");
             // dump first current limits for each of the branches
             try (BufferedWriter writer = Files.newBufferedWriter(rootDir.resolve(CURRENT_LIMITS_CSV), StandardCharsets.UTF_8)) {
                 for (Line l : network.getLines()) {
+                    if (exportConfig.isExportMainCCOnly() && !EchUtil.isInMainCc(l, exportConfig.isNoSwitch())) {
+                        continue;
+                    }
                     dumpLimits(dictionary, writer, l);
                 }
                 for (TwoWindingsTransformer twt : network.getTwoWindingsTransformers()) {
+                    if (exportConfig.isExportMainCCOnly() && !EchUtil.isInMainCc(twt, exportConfig.isNoSwitch())) {
+                        continue;
+                    }
                     dumpLimits(dictionary, writer, twt);
                 }
                 for (DanglingLine dl : network.getDanglingLines()) {
+                    if (exportConfig.isExportMainCCOnly() && !EchUtil.isInMainCc(dl, exportConfig.isNoSwitch())) {
+                        continue;
+                    }
                     dumpLimits(dictionary, writer, dl.getId(),
                             dl.getCurrentLimits(),
                             null,
@@ -273,6 +291,9 @@ private static void writeLimits(Network network, EurostagDictionary dictionary,
             }
             try (BufferedWriter writer = Files.newBufferedWriter(rootDir.resolve(VOLTAGE_LIMITS_CSV), StandardCharsets.UTF_8)) {
                 for (Bus b : EchUtil.getBuses(network, dictionary.getConfig())) {
+                    if (exportConfig.isExportMainCCOnly() && !(EchUtil.isInMainCc(b))) {
+                        continue;
+                    }
                     VoltageLevel vl = b.getVoltageLevel();
                     if (!Float.isNaN(vl.getLowVoltageLimit()) && !Float.isNaN(vl.getHighVoltageLimit())) {
                         writer.write(dictionary.getEsgId(b.getId()));
@@ -288,20 +309,17 @@ private static void writeLimits(Network network, EurostagDictionary dictionary,
             }
 
             //dump lines dictionary, for WP43 integration
-            dumpLinesDictionary(network, dictionary, rootDir);
+            dumpLinesDictionary(network, dictionary, rootDir, exportConfig);
             //dump buses dictionary, for WP43 integration
-            dumpBusesDictionary(network, dictionary, rootDir);
+            dumpBusesDictionary(network, dictionary, rootDir, exportConfig);
         }
 
         archive.as(ZipExporter.class).exportTo(os);
     }
 
-    private void writeLimits(Domain domain, OutputStream os) throws IOException {
-        writeLimits(network, dictionary, domain, os);
-    }
 
-    static void writeLimits(Network network, EurostagDictionary dictionary, OutputStream os) throws IOException {
-        writeLimits(network, dictionary, ShrinkWrap.createDomain(), os);
+    protected static void writeLimits(Network network, EurostagDictionary dictionary, OutputStream os, EurostagEchExportConfig exportConfig) throws IOException {
+        writeLimits(network, dictionary, ShrinkWrap.createDomain(), os, exportConfig);
     }
 
     private void writeScenarios(Domain domain, List<Contingency> contingencies, OutputStream os) throws IOException {
@@ -425,7 +443,7 @@ public void init(SimulationParameters parameters, Map<String, Object> context) t
                 writeAllWp43Configs(domain, os);
             }
             try (OutputStream os = computationManager.newCommonFile(LIMITS_ZIP_FILE_NAME)) {
-                writeLimits(domain, os);
+                writeLimits(network, dictionary, domain, os, exportConfig);
             }
         }
     }
@@ -457,7 +475,7 @@ private Command before(SimulationState state, Set<String> contingencyIds, Path w
             Files.write(workingDir.resolve(DDB_DICT_GENS_CSV), ((EurostagState) state).getDictGensCsv());
 
             try (OutputStream os = Files.newOutputStream(workingDir.resolve(LIMITS_ZIP_FILE_NAME))) {
-                writeLimits(domain.get(), os);
+                writeLimits(network, dictionary, domain.get(), os, exportConfig);
             }
         }
 
diff --git a/eurostag-integration/src/main/java/eu/itesla_project/eurostag/EurostagStabilization.java b/eurostag-integration/src/main/java/eu/itesla_project/eurostag/EurostagStabilization.java
index fd61c020..e0b1612d 100644
--- a/eurostag-integration/src/main/java/eu/itesla_project/eurostag/EurostagStabilization.java
+++ b/eurostag-integration/src/main/java/eu/itesla_project/eurostag/EurostagStabilization.java
@@ -102,6 +102,8 @@ public class EurostagStabilization implements Stabilization, EurostagConstants {
 
     private SimulationParameters parameters;
 
+    private final EurostagEchExporterFactory eurostagEchExporterFactory;
+
     public EurostagStabilization(Network network, ComputationManager computationManager, int priority) {
         this(network, computationManager, priority, EurostagConfig.load());
     }
@@ -115,6 +117,7 @@ public EurostagStabilization(Network network, ComputationManager computationMana
         this.priority = priority;
         ComponentDefaultConfig defaultConfig = ComponentDefaultConfig.load();
         this.ddbClient = defaultConfig.newFactoryImpl(DynamicDatabaseClientFactory.class).create(config.isDdbCaching());
+        this.eurostagEchExporterFactory = defaultConfig.newFactoryImpl(EurostagEchExporterFactory.class, EurostagEchExporterFactoryImpl.class);
         this.config = config;
 
         LOGGER.info(config.toString());
@@ -194,7 +197,7 @@ private void writeEch(Path workingDir) throws IOException {
             } else {
                 parameters.setStartMode(config.isLfWarmStart() ? EsgGeneralParameters.StartMode.WARM_START : EsgGeneralParameters.StartMode.FLAT_START);
             }
-            EsgNetwork networkEch = new EurostagEchExport(network, exportConfig, parallelIndexes, dictionary, fakeNodes).createNetwork(parameters);
+            EsgNetwork networkEch = eurostagEchExporterFactory.createEchExporter(network, exportConfig, parallelIndexes, dictionary, fakeNodes).createNetwork(parameters);
             networkModifier.hvLoadModelling(networkEch);
             new EsgWriter(networkEch, parameters, specialParameters).write(writer, network.getId() + "/" + network.getStateManager().getWorkingStateId());
         }
diff --git a/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgACDCVscConverter.java b/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgACDCVscConverter.java
new file mode 100644
index 00000000..9e5687a4
--- /dev/null
+++ b/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgACDCVscConverter.java
@@ -0,0 +1,203 @@
+/**
+ * Copyright (c) 2017, RTE (http://www.rte-france.com)
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+package eu.itesla_project.eurostag.network;
+
+import java.util.Objects;
+
+/**
+ * @author Christian Biasuzzi <christian.biasuzzi@techrain.it>
+ */
+public class EsgACDCVscConverter {
+
+    public enum ConverterState {
+        ON,
+        OFF
+    }
+
+    public enum DCControlMode {
+        AC_ACTIVE_POWER,
+        DC_VOLTAGE
+    }
+
+    public enum ACControlMode {
+        AC_VOLTAGE,
+        AC_REACTIVE_POWER,
+        AC_POWER_FACTOR
+    }
+
+    private final Esg8charName znconv; // converter name
+    private final Esg8charName dcNode1; // sending DC node name
+    private final Esg8charName dcNode2; // receiving DC node name
+    private final Esg8charName acNode; // AC node name
+    private final ConverterState xstate; // converter state ' ' ON; 'S' OFF
+    private final DCControlMode xregl; // DC control mode 'P' AC_ACTIVE_POWER; 'V' DC_VOLTAGE
+    private final ACControlMode xoper; // AC control mode 'V' AC_VOLTAGE; 'Q' AC_REACTIVE_POWER; 'A' AC_POWER_FACTOR
+    private final float rrdc; // resistance [Ohms]
+    private final float rxdc; // reactance [Ohms]
+    private final float pac; // AC active power setpoint [MW]. Only if DC control mode is 'P'
+    private final float pvd; // DC voltage setpoint [MW]. Only if DC control mode is 'V'
+    private final float pva; // AC voltage setpoint [kV]. Only if AC control mode is 'V'
+    private final float pre; // AC reactive power setpoint [Mvar]. Only if AC control mode is 'Q'
+    private final float pco; // AC power factor setpoint. Only if AC control mode is 'A'
+    private final float qvscsh; // Reactive sharing cofficient [%]. Only if AC control mode is 'V'
+    private final float pvscmin; // Minimum AC active power [MW]
+    private final float pvscmax; // Maximum AC active power [MW]
+    private final float qvscmin; // Minimum reactive power injected on AC node [kV]
+    private final float qvscmax; // Maximum reactive power injected on AC node [kV]
+    private final float vsb0; // Losses coefficient Beta0 [MW]
+    private final float vsb1; // Losses coefficient Beta1 [kW]
+    private final float vsb2; // Losses coefficient Beta2 [Ohms]
+    private final float mvm; // Initial AC modulated voltage magnitude [p.u.]
+    private final float mva; // Initial AC modulated voltage angle [deg]
+
+    public EsgACDCVscConverter(Esg8charName znconv,
+                               Esg8charName dcNode1,
+                               Esg8charName dcNode2,
+                               Esg8charName acNode,
+                               ConverterState xstate,
+                               DCControlMode xregl,
+                               ACControlMode xoper,
+                               float rrdc,
+                               float rxdc,
+                               float pac,
+                               float pvd,
+                               float pva,
+                               float pre,
+                               float pco,
+                               float qvscsh,
+                               float pvscmin,
+                               float pvscmax,
+                               float qvscmin,
+                               float qvscmax,
+                               float vsb0,
+                               float vsb1,
+                               float vsb2,
+                               float mvm,
+                               float mva) {
+        this.znconv = Objects.requireNonNull(znconv);
+        this.dcNode1 = Objects.requireNonNull(dcNode1);
+        this.dcNode2 = Objects.requireNonNull(dcNode2);
+        this.acNode = Objects.requireNonNull(acNode);
+        this.xstate = Objects.requireNonNull(xstate);
+        this.xregl = Objects.requireNonNull(xregl);
+        this.xoper = Objects.requireNonNull(xoper);
+        this.rrdc = rrdc;
+        this.rxdc = rxdc;
+        this.pac = pac;
+        this.pvd = pvd;
+        this.pva = pva;
+        this.pre = pre;
+        this.pco = pco;
+        this.qvscsh = qvscsh;
+        this.pvscmin = pvscmin;
+        this.pvscmax = pvscmax;
+        this.qvscmin = qvscmin;
+        this.qvscmax = qvscmax;
+        this.vsb0 = vsb0;
+        this.vsb1 = vsb1;
+        this.vsb2 = vsb2;
+        this.mvm = mvm;
+        this.mva = mva;
+    }
+
+
+    public Esg8charName getZnconv() {
+        return znconv;
+    }
+
+    public Esg8charName getDcNode1() {
+        return dcNode1;
+    }
+
+    public Esg8charName getDcNode2() {
+        return dcNode2;
+    }
+
+    public Esg8charName getAcNode() {
+        return acNode;
+    }
+
+    public ConverterState getXstate() {
+        return xstate;
+    }
+
+    public DCControlMode getXregl() {
+        return xregl;
+    }
+
+    public ACControlMode getXoper() {
+        return xoper;
+    }
+
+    public float getRrdc() {
+        return rrdc;
+    }
+
+    public float getRxdc() {
+        return rxdc;
+    }
+
+    public float getPac() {
+        return pac;
+    }
+
+    public float getPvd() {
+        return pvd;
+    }
+
+    public float getPva() {
+        return pva;
+    }
+
+    public float getPre() {
+        return pre;
+    }
+
+    public float getPco() {
+        return pco;
+    }
+
+    public float getQvscsh() {
+        return qvscsh;
+    }
+
+    public float getPvscmin() {
+        return pvscmin;
+    }
+
+    public float getPvscmax() {
+        return pvscmax;
+    }
+
+    public float getQvscmin() {
+        return qvscmin;
+    }
+
+    public float getQvscmax() {
+        return qvscmax;
+    }
+
+    public float getVsb0() {
+        return vsb0;
+    }
+
+    public float getVsb1() {
+        return vsb1;
+    }
+
+    public float getVsb2() {
+        return vsb2;
+    }
+
+    public float getMvm() {
+        return mvm;
+    }
+
+    public float getMva() {
+        return mva;
+    }
+}
diff --git a/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgDCLink.java b/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgDCLink.java
new file mode 100644
index 00000000..97e948a9
--- /dev/null
+++ b/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgDCLink.java
@@ -0,0 +1,60 @@
+/**
+ * Copyright (c) 2017, RTE (http://www.rte-france.com)
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+package eu.itesla_project.eurostag.network;
+
+import java.util.Objects;
+
+/**
+ * @author Christian Biasuzzi <christian.biasuzzi@techrain.it>
+ */
+public class EsgDCLink {
+
+    public enum LinkStatus {
+        ON,
+        OFF
+    }
+
+    private final Esg8charName node1Name; // sending node name
+    private final Esg8charName node2Name; // receiving node name
+    private final char xpp; // parallel index
+    private final float rldc; // total link resistance [p.u.]
+    private final LinkStatus linkStatus; // ' ' ON; 'S' OFF
+
+    public EsgDCLink(Esg8charName node1Name, Esg8charName node2Name, char xpp, float rldc, LinkStatus linkStatus) {
+        this.node1Name = Objects.requireNonNull(node1Name);
+        this.node2Name = Objects.requireNonNull(node2Name);
+        this.linkStatus = Objects.requireNonNull(linkStatus);
+        this.xpp = xpp;
+        this.rldc = rldc;
+    }
+
+    public Esg8charName getNode1Name() {
+        return node1Name;
+    }
+
+    public Esg8charName getNode2Name() {
+        return node2Name;
+    }
+
+    public char getXpp() {
+        return xpp;
+    }
+
+    public float getRldc() {
+        return rldc;
+    }
+
+    public LinkStatus getLinkStatus() {
+        return linkStatus;
+    }
+
+    @Override
+    public String toString() {
+        return node1Name + "-" + node2Name + "-" + xpp + "";
+    }
+
+}
diff --git a/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgDCNode.java b/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgDCNode.java
new file mode 100644
index 00000000..fe881b4a
--- /dev/null
+++ b/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgDCNode.java
@@ -0,0 +1,44 @@
+/**
+ * Copyright (c) 2017, RTE (http://www.rte-france.com)
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+package eu.itesla_project.eurostag.network;
+
+import java.util.Objects;
+
+/**
+ * @author Christian Biasuzzi <christian.biasuzzi@techrain.it>
+ */
+public class EsgDCNode {
+
+    private final Esg2charName area; // zone identifier
+    private final Esg8charName name; // node name
+    private final float vbase; // base voltage [kV]
+    private final float vinit; // Initial voltage [p.u.]
+
+    public EsgDCNode(Esg2charName area, Esg8charName name, float vbase, float vinit) {
+        this.area = Objects.requireNonNull(area);
+        this.name = Objects.requireNonNull(name);
+        this.vbase = vbase;
+        this.vinit = vinit;
+    }
+
+    public Esg2charName getArea() {
+        return area;
+    }
+
+    public Esg8charName getName() {
+        return name;
+    }
+
+    public float getVbase() {
+        return vbase;
+    }
+
+    public float getVinit() {
+        return vinit;
+    }
+
+}
diff --git a/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgNetwork.java b/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgNetwork.java
index 256c34ec..940a775c 100644
--- a/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgNetwork.java
+++ b/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/EsgNetwork.java
@@ -35,6 +35,9 @@ public class EsgNetwork {
     private final Map<String, EsgLoad> loads = new LinkedHashMap<>();
     private final Map<String, EsgCapacitorOrReactorBank> capacitorsOrReactorBanks = new LinkedHashMap<>();
     private final Map<String, EsgStaticVarCompensator> staticVarCompensators = new LinkedHashMap<>();
+    private final Map<String, EsgDCNode> dcNodes = new LinkedHashMap<>();
+    private final Map<String, EsgDCLink> dcLinks = new LinkedHashMap<>();
+    private final Map<String, EsgACDCVscConverter> vscConverters = new LinkedHashMap<>();
 
     private void checkBranchName(EsgBranchName name) {
         if (getNode(name.getNode1Name().toString()) == null) {
@@ -398,4 +401,71 @@ public void addStaticVarCompensator(EsgStaticVarCompensator svc) {
         }
         staticVarCompensators.put(svc.getZnamsvc().toString(), svc);
     }
+
+    public Collection<EsgDCNode> getDCNodes() {
+        return dcNodes.values();
+    }
+
+    public EsgDCNode getDCNode(String name) {
+        return dcNodes.get(name);
+    }
+
+    public void addDCNode(EsgDCNode node) {
+        if (dcNodes.containsKey(node.getName().toString())) {
+            throw new IllegalArgumentException("DC node '" + node.getName() + "' already exists");
+        }
+        dcNodes.put(node.getName().toString(), node);
+    }
+
+    public void removeDCNode(String node) {
+        if (!dcNodes.containsKey(node)) {
+            throw new IllegalArgumentException("DC node '" + node + "' doesn't exists");
+        }
+        dcNodes.remove(node);
+    }
+
+    public Collection<EsgDCLink> getDCLinks() {
+        return dcLinks.values();
+    }
+
+    public EsgDCLink getDCLink(String dcLinkStr) {
+        return dcLinks.get(dcLinkStr);
+    }
+
+    public void addDCLink(EsgDCLink dclink) {
+        if (dcLinks.containsKey(dclink.toString())) {
+            throw new IllegalArgumentException("DC Link '" + dcLinks.toString() + "' already exists");
+        }
+        dcLinks.put(dclink.toString(), dclink);
+    }
+
+    public void removeDCLink(String dcLinkStr) {
+        if (!lines.containsKey(dcLinkStr)) {
+            throw new IllegalArgumentException("DC Link '" + dcLinkStr + "' doesn't exists");
+        }
+        dcLinks.remove(dcLinkStr);
+    }
+
+    public Collection<EsgACDCVscConverter> getACDCVscConverters() {
+        return vscConverters.values();
+    }
+
+    public EsgACDCVscConverter getACDCVscConverter(String name) {
+        return vscConverters.get(name);
+    }
+
+    public void addACDCVscConverter(EsgACDCVscConverter vscConverter) {
+        if (vscConverters.containsKey(vscConverter.getZnconv().toString())) {
+            throw new IllegalArgumentException("ACDCVscConverter '" + vscConverter.getZnconv() + "' already exists");
+        }
+        vscConverters.put(vscConverter.getZnconv().toString(), vscConverter);
+    }
+
+    public void removeACDCVscConverter(String name) {
+        if (!vscConverters.containsKey(name)) {
+            throw new IllegalArgumentException("ACDCVscConverter '" + name + "' doesn't exists");
+        }
+        vscConverters.remove(name);
+    }
+
 }
diff --git a/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/io/EsgWriter.java b/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/io/EsgWriter.java
index cd1d80ed..e1566bf5 100644
--- a/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/io/EsgWriter.java
+++ b/eurostag-network/src/main/java/eu/itesla_project/eurostag/network/io/EsgWriter.java
@@ -1,4 +1,5 @@
 /**
+ * Copyright (c) 2017, RTE (http://www.rte-france.com)
  * Copyright (c) 2016, All partners of the iTesla project (http://www.itesla-project.eu/consortium)
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -10,7 +11,9 @@
 
 import java.io.IOException;
 import java.io.Writer;
+import java.util.Comparator;
 import java.util.Objects;
+import java.util.stream.Collectors;
 
 /**
  * @author Geoffroy Jamgotchian <geoffroy.jamgotchian at rte-france.com>
@@ -382,6 +385,101 @@ private static void writeStaticVarCompensator(EsgStaticVarCompensator svc, Recor
         recordWriter.newLine();
     }
 
+    private static void writeDCNode(EsgDCNode dcNode, RecordWriter recordWriter) throws IOException {
+        recordWriter.addValue("DC N", 1, 4);
+        recordWriter.addValue(dcNode.getName().toString(), 6, 13);
+        recordWriter.addValue(dcNode.getArea().toString(), 15, 16);
+        recordWriter.addValue(dcNode.getVbase(), 18, 25);
+        recordWriter.addValue(dcNode.getVinit(), 27, 34);
+        recordWriter.newLine();
+    }
+
+    private static char toChar(EsgDCLink.LinkStatus linkStatus) {
+        switch (linkStatus) {
+            case ON: return ' ';
+            case OFF: return 'S';
+            default: throw new InternalError();
+        }
+    }
+
+    private static void writeDCLink(EsgDCLink link, RecordWriter recordWriter) throws IOException {
+        recordWriter.addValue("DC L", 1, 4);
+        recordWriter.addValue(link.getNode1Name().toString(), 6, 13);
+        recordWriter.addValue(link.getNode2Name().toString(), 15, 22);
+        recordWriter.addValue(link.getXpp(), 24);
+        recordWriter.addValue(link.getRldc(), 26, 33);
+        recordWriter.addValue(toChar(link.getLinkStatus()), 35, 35);
+        recordWriter.newLine();
+    }
+
+    private static char toChar(EsgACDCVscConverter.ConverterState state) {
+        switch (state) {
+            case OFF: return 'S';
+            case ON: return ' ';
+            default: throw new InternalError();
+        }
+    }
+
+    private static char toChar(EsgACDCVscConverter.DCControlMode dcMode) {
+        switch (dcMode) {
+            case AC_ACTIVE_POWER: return 'P';
+            case DC_VOLTAGE: return 'V';
+            default: throw new InternalError();
+        }
+    }
+
+    private static char toChar(EsgACDCVscConverter.ACControlMode acMode) {
+        switch (acMode) {
+            case AC_VOLTAGE: return 'V';
+            case AC_REACTIVE_POWER: return 'Q';
+            case AC_POWER_FACTOR: return 'A';
+            default: throw new InternalError();
+        }
+    }
+
+    private static void writeACDCVscConverter(EsgACDCVscConverter vscConverter, RecordWriter recordWriter) throws IOException {
+        recordWriter.addValue("DC V", 1, 4);
+        recordWriter.addValue(vscConverter.getZnconv().toString(), 6, 13);
+        recordWriter.addValue(vscConverter.getDcNode1().toString(), 15, 22);
+        recordWriter.addValue(vscConverter.getDcNode2().toString(), 24, 31);
+        recordWriter.addValue(vscConverter.getAcNode().toString(), 33, 40);
+        recordWriter.addValue(toChar(vscConverter.getXstate()), 42, 42);
+        recordWriter.addValue(toChar(vscConverter.getXregl()), 44, 44);
+        recordWriter.addValue(toChar(vscConverter.getXoper()), 46, 46);
+        recordWriter.addValue(vscConverter.getRrdc(), 48, 55);
+        recordWriter.addValue(vscConverter.getRxdc(), 57, 64);
+        if (!Float.isNaN(vscConverter.getPac())) {
+            recordWriter.addValue(vscConverter.getPac(), 66, 73);
+        }
+        if (!Float.isNaN(vscConverter.getPvd())) {
+            recordWriter.addValue(vscConverter.getPvd(), 75, 82);
+        }
+        if (!Float.isNaN(vscConverter.getPva())) {
+            recordWriter.addValue(vscConverter.getPva(), 84, 91);
+        }
+        if (!Float.isNaN(vscConverter.getPre())) {
+            recordWriter.addValue(vscConverter.getPre(), 93, 100);
+        }
+        if (!Float.isNaN(vscConverter.getPco())) {
+            recordWriter.addValue(vscConverter.getPco(), 102, 109);
+        }
+        if (!Float.isNaN(vscConverter.getQvscsh())) {
+            recordWriter.addValue(vscConverter.getQvscsh(), 111, 118);
+        }
+        recordWriter.newLine();
+        recordWriter.addValue("DC V", 1, 4);
+        recordWriter.addValue(vscConverter.getPvscmin(), 6, 13);
+        recordWriter.addValue(vscConverter.getPvscmax(), 15, 22);
+        recordWriter.addValue(vscConverter.getQvscmin(), 24, 31);
+        recordWriter.addValue(vscConverter.getQvscmax(), 33, 40);
+        recordWriter.addValue(vscConverter.getVsb0(), 42, 49);
+        recordWriter.addValue(vscConverter.getVsb1(), 51, 58);
+        recordWriter.addValue(vscConverter.getVsb2(), 60, 67);
+        recordWriter.addValue(vscConverter.getMvm(), 69, 76);
+        recordWriter.addValue(vscConverter.getMva(), 78, 85);
+        recordWriter.newLine();
+    }
+
     public void write(Writer writer) throws IOException {
         write(writer, null);
     }
@@ -400,7 +498,10 @@ public void write(Writer writer, String comment) throws IOException {
         writeGeneralComment(recordWriter, comment);
 
         if (network.getAreas().size() > 0) {
-            for (EsgArea area : network.getAreas()) {
+            for (EsgArea area : network.getAreas()
+                    .stream()
+                    .sorted(Comparator.comparing(EsgArea::getType).thenComparing(area -> area.getName().toString()))
+                    .collect(Collectors.toList())) {
                 writeArea(area, recordWriter);
             }
             recordWriter.newLine();
@@ -468,6 +569,28 @@ public void write(Writer writer, String comment) throws IOException {
             }
             recordWriter.newLine();
         }
-    }
 
+        if (network.getDCNodes().size() > 0) {
+            for (EsgDCNode dcNode : network.getDCNodes()) {
+                writeDCNode(dcNode, recordWriter);
+            }
+            recordWriter.newLine();
+        }
+
+
+        if (network.getDCLinks().size() > 0) {
+            for (EsgDCLink dcLink : network.getDCLinks()) {
+                writeDCLink(dcLink, recordWriter);
+            }
+            recordWriter.newLine();
+        }
+
+
+        if (network.getACDCVscConverters().size() > 0) {
+            for (EsgACDCVscConverter vscConv : network.getACDCVscConverters()) {
+                writeACDCVscConverter(vscConv, recordWriter);
+            }
+            recordWriter.newLine();
+        }
+    }
 }
diff --git a/eurostag-step-up-transformer/src/main/java/eu/itesla_project/iidm/ddb/eurostag/EurostagStepUpTransformerInserter.java b/eurostag-step-up-transformer/src/main/java/eu/itesla_project/iidm/ddb/eurostag/EurostagStepUpTransformerInserter.java
index 4cad59fe..77cd6aa9 100644
--- a/eurostag-step-up-transformer/src/main/java/eu/itesla_project/iidm/ddb/eurostag/EurostagStepUpTransformerInserter.java
+++ b/eurostag-step-up-transformer/src/main/java/eu/itesla_project/iidm/ddb/eurostag/EurostagStepUpTransformerInserter.java
@@ -7,6 +7,7 @@
  */
 package eu.itesla_project.iidm.ddb.eurostag;
 
+import com.google.common.collect.Lists;
 import com.powsybl.computation.ComputationManager;
 import com.powsybl.iidm.network.*;
 import com.powsybl.iidm.network.ReactiveCapabilityCurve.Point;
@@ -29,6 +30,7 @@
 import java.util.function.Function;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
+import java.util.stream.StreamSupport;
 
 /**
  *
@@ -530,7 +532,24 @@ private static void removeStepUpTransformersAlreadyPresents(Network n, List<Stri
                 continue;
             }
 
-            for (Bus lvBus : lvVl.getBusBreakerView().getBuses()) {
+            //iterate in reverse order to not incur in 'bus has been invalidated' errors
+            List<String> lvBusIds = Lists.newArrayList(StreamSupport.stream(lvVl.getBusView().getBuses().spliterator(), false).map(b -> b.getId()).collect(Collectors.toCollection(LinkedList::new)).descendingIterator());
+            for (String lvBusId : lvBusIds) {
+                Bus lvBus = n.getVoltageLevel(lvVlId).getBusView().getBus(lvBusId);
+                if (lvBus == null) {
+                    String errMsg = "lvVlId: " + lvVlId + "; lvBus with id: " + lvBusId + " not found";
+                    LOGGER.error(errMsg);
+                    throw new RuntimeException(errMsg);
+                }
+
+                float v = lvBus.getV();
+                if (Float.isNaN(v)) {
+                    v = lvVl.getNominalV();
+                }
+                float a = lvBus.getAngle();
+                if (Float.isNaN(a)) {
+                    a = 0;
+                }
 
                 // check there is:
                 //    - one two windings transformers
@@ -587,10 +606,10 @@ public void visitThreeWindingsTransformer(ThreeWindingsTransformer transformer,
 
                 if (twtLs.isEmpty()) {
                     for (Generator g : genLs) {
-                        g.remove();
+                        LOGGER.warn("stator voltage level: {}, bus: {}; no connected two-winding-transformer found, no step up transformer removed for generator: {}", lvVlId, lvBus.getId(), g.getId());
                     }
                     for (Load aux : auxLs) {
-                        aux.remove();
+                        LOGGER.warn("stator voltage level: {}, bus: {}; no connected two-winding-transformer found, no step up transformer removed for load: {}", lvVlId, lvBus.getId(), aux.getId());
                     }
                     continue;
                 }
@@ -609,10 +628,10 @@ public void visitThreeWindingsTransformer(ThreeWindingsTransformer transformer,
 
                 VoltageLevel hvVl;
                 Bus hvBus;
-                if (twt.getTerminal1().getBusBreakerView().getConnectableBus() == lvBus) {
+                if (twt.getTerminal1().getBusView().getConnectableBus() == lvBus) {
                     hvVl = twt.getTerminal2().getVoltageLevel();
                     hvBus = twt.getTerminal2().getBusBreakerView().getConnectableBus();
-                } else if (twt.getTerminal2().getBusBreakerView().getConnectableBus() == lvBus) {
+                } else if (twt.getTerminal2().getBusView().getConnectableBus() == lvBus) {
                     hvVl = twt.getTerminal1().getVoltageLevel();
                     hvBus = twt.getTerminal1().getBusBreakerView().getConnectableBus();
                 } else {
@@ -621,9 +640,9 @@ public void visitThreeWindingsTransformer(ThreeWindingsTransformer transformer,
 
                 Function<StateVariable, StateVariable> fct = sv -> {
                     StateVariable otherSideSv;
-                    if (twt.getTerminal2().getBusBreakerView().getConnectableBus() == lvBus) {
+                    if (twt.getTerminal2().getBusView().getConnectableBus().getId().equals(lvBus.getId())) {
                         otherSideSv = transformerModel.toSv1(new StateVariable(-sv.p, -sv.q, sv.u, sv.theta));
-                    } else if (twt.getTerminal1().getBusBreakerView().getConnectableBus() == lvBus) {
+                    } else if (twt.getTerminal1().getBusView().getConnectableBus().getId().equals(lvBus.getId())) {
                         otherSideSv = transformerModel.toSv2(new StateVariable(-sv.p, -sv.q, sv.u, sv.theta));
                     } else {
                         throw new RuntimeException("Unexpected stator substation topology");
@@ -648,14 +667,6 @@ public void visitThreeWindingsTransformer(ThreeWindingsTransformer transformer,
 
                 for (Load aux : auxLs) {
 
-                    float v = lvBus.getV();
-                    if (Float.isNaN(v)) {
-                        v = lvVl.getNominalV();
-                    }
-                    float a = lvBus.getAngle();
-                    if (Float.isNaN(a)) {
-                        a = 0;
-                    }
 
                     StateVariable hlSvAux = fct.apply(new StateVariable(-aux.getP0(), -aux.getQ0(), v, a));
 
diff --git a/iidm-ddb/iidm-ddb-eurostag-import-export/src/main/java/eu/itesla_project/iidm/ddb/eurostag_imp_exp/DdbDtaImpExp.java b/iidm-ddb/iidm-ddb-eurostag-import-export/src/main/java/eu/itesla_project/iidm/ddb/eurostag_imp_exp/DdbDtaImpExp.java
index b30e25a1..57ec5f2d 100644
--- a/iidm-ddb/iidm-ddb-eurostag-import-export/src/main/java/eu/itesla_project/iidm/ddb/eurostag_imp_exp/DdbDtaImpExp.java
+++ b/iidm-ddb/iidm-ddb-eurostag-import-export/src/main/java/eu/itesla_project/iidm/ddb/eurostag_imp_exp/DdbDtaImpExp.java
@@ -1,19 +1,21 @@
 /**
- * Copyright (c) 2016, All partners of the iTesla project (http://www.itesla-project.eu/consortium)
+ * Copyright (c) 2016 All partners of the iTesla project (http://www.itesla-project.eu/consortium)
+ * Copyright (c) 2018, RTE (http://www.rte-france.com)
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
 package eu.itesla_project.iidm.ddb.eurostag_imp_exp;
 
+import com.google.common.base.Strings;
 import com.google.common.collect.Sets;
+import com.powsybl.iidm.network.*;
 import com.powsybl.iidm.network.util.ConnectedComponents;
+import com.powsybl.iidm.network.util.Identifiables;
 import eu.itesla_project.iidm.ddb.eurostag_imp_exp.utils.Utils;
 import eu.itesla_project.iidm.ddb.model.*;
 import eu.itesla_project.iidm.ddb.service.DDBManager;
 import eu.itesla_project.iidm.ejbclient.EjbClientCtx;
-import com.powsybl.iidm.network.*;
-import com.powsybl.iidm.network.util.Identifiables;
 import itesla.converter.Converter;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -27,6 +29,7 @@
 import java.nio.file.attribute.BasicFileAttributes;
 import java.text.ParseException;
 import java.util.*;
+import java.util.stream.Collectors;
 
 /**
  *
@@ -80,7 +83,7 @@ public class DdbDtaImpExp implements DynamicDatabaseClient {
             //              {"M22D", "I-PHI injector - type Fortescue"},
             //              {"M23",  "IR-II injector"},
             //              {"M23D", "IR-II injector - type Fortescue"},
-            //              {"M50",  "Converter"},
+            {"M50",  "Converter"},
             //              {"M50D", "Converter - type Fortescue"},
             {"MA",  "Macro-Automaton"},
             ////          {"R",    "Macroblock"}
@@ -295,6 +298,9 @@ public void feedDDBWithEurostagData(Path inputFile,
                 case "M21":
                     dbId = populateDDB_M21(zone, dicoMap, ddbmanager, eurostagSim);
                     break;
+                case "M50":
+                    dbId = populateDDB_M50(zone, dicoMap, ddbmanager, eurostagSim);
+                    break;
                 case "R":
                     dbId = populateDDB_R(zone, dicoMap, ddbmanager, eurostagSim, regsMapping);
                     break;
@@ -493,16 +499,144 @@ public String populateDDB_M21(EurostagRecord zone, Map<String, String> amap,
 
         return cimId;
     }
+
+    public String populateDDB_M50(EurostagRecord zone, Map<String, String> amap,
+                                  DDBManager ddbmanager, SimulatorInst eurostagSim) {
+        // here we assume that the simulator with the required version already
+        // exists
+        if (eurostagSim == null) {
+            throw new RuntimeException("Eurostag simulator could not be null");
+        }
+
+        if (!"M50".equals(zone.getTypeName())) {
+            throw new RuntimeException("not expected type M50: " + zone);
+        }
+
+        log.debug("-Creating DDB component {} ", zone.getTypeName());
+        String mName = (String) zone.getData().get("machine.name");
+        String cimId = amap.get(mName);
+        if ((cimId == null) || ("".equals(cimId))) {
+            throw new RuntimeException(mName + ": cimId not found in mapping.");
+        }
+
+        if (!equipmentsTypeMap.contains(cimId)) {
+            equipmentsTypeMap.put(cimId, zone.getTypeName());
+        }
+
+        Equipment eq1 = ddbmanager.findEquipment(cimId);
+        if ((eq1 != null) && updateFlag) {
+            Set<String> connectedInternals = getConnectedInternals(cimId, ddbmanager);
+
+            //remove this equipment graph
+            log.info("- removing existing equipment {}", cimId);
+            removeEquipment(cimId, ddbmanager);
+            eq1 = null;
+
+            for (String internalId : connectedInternals) {
+                log.info("- removing existing connected internal {}", internalId);
+                removeInternal(internalId, ddbmanager);
+            }
+
+        }
+
+        String mtcDdbid = MTC_PREFIX_NAME + zone.getKeyName();
+        ModelTemplateContainer mtc1 = ddbmanager
+                .findModelTemplateContainer(mtcDdbid);
+        if (mtc1 == null) {
+            throw new RuntimeException(" template container " + mtcDdbid
+                    + " not defined! ");
+        }
+
+        ParametersContainer pc1 = ddbmanager.findParametersContainer(mName);
+        if (pc1 == null) {
+            log.debug("-- creating Parameters Container " + mName + " plus parameters.");
+            pc1 = new ParametersContainer(mName);
+            Parameters pars = new Parameters(eurostagSim);
+            for (String varName : zone.getData().keySet()) {
+                String varFType = DtaParser.getVarFType(zone.typeName, varName);
+                Object varValue = zone.getData().get(varName);
+                if (log.isDebugEnabled()) {
+                    log.trace("----" + varName + " = " + varValue + ", " + varFType);
+                }
+                if (varFType.startsWith("F")) {
+                    if (varValue != null) {
+                        pars.addParameter(new ParameterFloat(varName,
+                                new Float((Double) varValue)));
+                    } else {
+                        pars.addParameter(new ParameterFloat(varName, null));
+                    }
+                } else if (varFType.startsWith("A")) {
+                    pars.addParameter(new ParameterString(varName,
+                            (String) varValue));
+                } else {
+                    log.error(varFType + " not handled");
+                }
+            }
+            pc1.getParameters().add(pars);
+            pc1 = ddbmanager.save(pc1);
+        } else {
+            log.debug("-- Parameters Container container " + mName
+                    + " already defined, id: " + pc1.getId());
+            // ddbmanager.delete(pc1);
+        }
+
+        if (eq1 == null) {
+            log.info("-- creating Equipment " + cimId + "; eurostag name is: "
+                    + mName);
+            eq1 = new Equipment(cimId);
+            eq1.setModelContainer(mtc1);
+            eq1.setParametersContainer(pc1);
+            eq1 = ddbmanager.save(eq1);
+        } else {
+            log.warn("-- Equipment  " + cimId + " already defined, id: "
+                    + eq1.getId());
+        }
+
+        return cimId;
+    }
+
     private String populateDDB_R(EurostagRecord zone, Map<String, String> amap,
             DDBManager ddbmanager, SimulatorInst eurostagSim, Map<String, Path> regsMapping) {
 
 
         log.debug("-Creating DDB component (R) " + zone);
 
+        String machineName = (String) zone.getData().get("machine.name");
+
+        //macroblock's coupling parameters - map machine IDs to iidm IDs
+        zone.getData().keySet().stream()
+                .filter(parName -> parName.startsWith("coupling.par") && (zone.getData().get(parName) != null) && (!"".equals(zone.getData().get(parName))))
+                .forEach(parName -> {
+                    String parValue = zone.getData().get(parName).toString();
+                    String couplingtype = parValue.substring(0, 2);
+                    //log.info("machine: {} - coupling macroblock parameter: {} = {}", machineName, parName, parValue);
+                    switch (couplingtype) {
+                        case "M ":
+                        case "N#":
+                            String couplingMachineName = parValue.substring(3).trim();
+                            String iidmCouplingMachineName = amap.get(couplingMachineName);
+                            if (iidmCouplingMachineName != null) {
+                                String newparValue = couplingtype + " " + iidmCouplingMachineName;
+                                zone.getData().put(parName, newparValue);
+                                log.info("macroblock {} - coupling parameter {} = '{}' - mapped to '{}'", machineName, parName, parValue, newparValue);
+                            } else {
+                                String errMsg = "macroblock " + machineName + " - coupling parameter " + parName + " = " + parValue + "  not mapped";
+                                log.error(errMsg);
+                                throw new RuntimeException(errMsg);
+                            }
+                            break;
+                        case "N ":
+                            log.warn("macroblock {} - coupling parameter: {} = {} - coupling type {} not stored in DDB", machineName, parName, parValue, couplingtype);
+                            break;
+                        default:
+                            log.warn("macroblock {} - coupling parameter: {} = {} coupling type {} not supported !", machineName, parName, parValue, couplingtype);
+                    }
+                });
+
         String macroblockName = (String) zone.getData().get(
                 PAR_MACROBLOCK_NAME);
         int paramSetNum = (int) zone.getData().get("psetnum");
-        String machineName = (String) zone.getData().get("machine.name");
+
         String nativeId = amap.get(machineName);
 
         if ((nativeId == null) || ("".equals(nativeId))) {
@@ -937,6 +1071,17 @@ public void dumpDtaFile(Path workingDir, String fileName,
                 }
             }
 
+            //add vscConverter stations to the equipment list
+            for (HvdcLine hvdcLine : Identifiables.sort(network.getHvdcLines())) {
+                // skip lines with converter stations not in the main connected component
+                if (configExport.isExportMainCCOnly() && (!isInMainCc(hvdcLine.getConverterStation1(), configExport.isNoSwitch()) || !isInMainCc(hvdcLine.getConverterStation2(), configExport.isNoSwitch()))) {
+                    log.warn("skipped HVDC line {}: at least one converter station is not in main component", hvdcLine.getId());
+                    continue;
+                }
+                cimIds.add(hvdcLine.getConverterStation1().getId());
+                cimIds.add(hvdcLine.getConverterStation2().getId());
+            }
+
             // writing a .dta
             DtaParser.dumpHeader(new Date(), eurostagVersion, dtaOutStream);
 
@@ -1216,6 +1361,9 @@ public void dumpData(Equipment inst, SimulatorInst simInst, DDBManager ddbmanage
             case "M21":
                 zoneTypeName = "M21";
                 break;
+            case "M50":
+                zoneTypeName = "M50";
+                break;
             case "R":
                 zoneTypeName = "R";
                 break;
@@ -1275,6 +1423,19 @@ public void dumpData(Equipment inst, SimulatorInst simInst, DDBManager ddbmanage
                     //                }
                 }
                 break;
+            case "M50":
+                if (iidm2eurostagId != null) {
+                    String substMachineName = iidm2eurostagId.get(inst.getCimId());
+                    if ((substMachineName != null) && (!"".equals(substMachineName))) {
+                        zm.put("machine.name", substMachineName);
+                    }
+
+                    if (log.isDebugEnabled()) {
+                        log.debug(" machine.name mapped to new eurostag id: " + substMachineName);
+                    }
+
+                }
+                break;
             default:
                 break;
         }
@@ -1527,21 +1688,86 @@ public void dumpData(Internal inst, SimulatorInst simInst, DDBManager ddbmanager
                 zm.put("coupling.par9", null);
             }
         } else {
-            if (couplingDataExists) {
-                log.warn("coupling macroblock data in ddb -  macroblock name: " + zm.get("macroblock.name") + "; machine name: " + machineName);
-            }
-            zm.put("coupling.par1", null);
-            zm.put("coupling.par2", null);
-            zm.put("coupling.par3", null);
-            zm.put("coupling.par4", null);
-            zm.put("coupling.par5", null);
-            zm.put("coupling.par6", null);
-            zm.put("coupling.par7", null);
-            zm.put("coupling.par8", null);
-            zm.put("coupling.par9", null);
-            if (log.isDebugEnabled()) {
-                log.trace(" coupling.par(s) mapped to empty string");
+            //handle specific M50 model template (VSC)
+            if ((MTC_PREFIX_NAME + "M50").equals(eq.getModelContainer().getDdbId())) {
+                if (isMacroblockIncluded(network.getVscConverterStation(eq.getCimId()), zm)) {
+                    //filter out meta-parameters (i.e. #PMODE #VMODE)
+                    HashMap<String, Object> zmFiltered = zm.entrySet().stream()
+                            .filter(p -> !p.getKey().startsWith("#"))
+                            .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue, (key, value) -> key, HashMap::new));
+                    zm = zmFiltered;
+                } else {
+                    //just skip this macroblock section
+                    return;
+                }
             }
+
+            // set coupling macroblock parameters
+            log.debug("Fixing macroblock's coupling parameters - id: {}, machine name: {} original macrobloc data: {}", eq.getCimId(), machineName, zm);
+            HashMap<String, Object> zmap = zm;
+            zm.keySet().stream()
+                    .filter(parName -> parName.startsWith("coupling.par") && (zmap.get(parName) != null) && (!"".equals(zmap.get(parName))))
+                    .forEach(parName -> {
+                        String parValue = zmap.get(parName).toString();
+                        String couplingtype = parValue.substring(0, 2);
+                        String newParValue = null;
+                        switch (couplingtype) {
+                            case "M ":
+                                //in DDB, in this specific case (machine name coupling), it is stored the iidm ID of the machine (set at DDB's loading time)
+                                String couplingMachineName = parValue.substring(3);
+                                String iidmCouplingMachineName = iidm2eurostagId.get(couplingMachineName);
+                                if (iidmCouplingMachineName != null) {
+                                    newParValue = couplingtype + " " + Strings.padEnd(iidmCouplingMachineName, 8, ' ');
+                                } else {
+                                    throw new RuntimeException("id: " + eq.getCimId() + ", name: " + machineName + ", coupling parameter " + parName + "=" + parValue + " -  could not map to any machine");
+                                }
+                                break;
+                            case "N#":
+                                //in DDB, in this specific case N# (node name coupling), it is stored the iidm ID of the machine whose bus has to be retrieved
+                                //note that N# is not Eurostag compliant identifier: it must be converted to 'N'
+                                String refMachineName = parValue.substring(3);
+                                Injection injection = (Injection) network.getIdentifiable(refMachineName);
+                                if (injection == null) {
+                                    throw new RuntimeException("id: " + eq.getCimId() + ", name: " + machineName + ", coupling parameter " + parName + "=" + parValue + " -  could not find any injection with id: " + refMachineName);
+                                }
+
+                                Bus coupledBus = null;
+                                //if the referenced machine is a Generator, deal with stepuptransformers
+                                //fetch the high-voltage node of the step-up transformer of the unit
+                                Generator g;
+                                if ((g = network.getGenerator(injection.getId())) != null) {
+                                    VoltageLevel vlGen = g.getTerminal().getVoltageLevel();
+                                    if (vlGen != null) {
+                                        TwoWindingsTransformer twt = network.getTwoWindingsTransformerStream().filter(t -> vlGen.getId().equals(t.getTerminal2().getVoltageLevel().getId())).findFirst().orElse(null);
+                                        if (twt != null) {
+                                            coupledBus = getBus(twt.getTerminal1(), configExport.isNoSwitch());
+                                        }
+                                    }
+                                }
+                                if (coupledBus == null) {
+                                    coupledBus = getBus(injection.getTerminal(), configExport.isNoSwitch());
+                                }
+                                if (coupledBus == null) {
+                                    throw new RuntimeException("id: " + eq.getCimId() + ", name: " + machineName + ", coupling parameter " + parName + "=" + parValue + " - bus not connected to a bus and not connectable");
+                                }
+                                String newBusEsgId = iidm2eurostagId.containsKey(coupledBus.getId()) ? iidm2eurostagId.get(coupledBus.getId()) : null;
+                                if (newBusEsgId != null) {
+                                    newParValue = "N " + " " + Strings.padEnd(newBusEsgId, 8, ' ');
+                                } else {
+                                    throw new RuntimeException("id: " + eq.getCimId() + ", name: " + machineName + ", coupling parameter " + parName + "=" + parValue + " - unknown mapping for bus: " + coupledBus.getId());
+                                }
+                                break;
+                            case "N ":
+                                log.warn("macroblock {} - coupling parameter {} = {}; coupling type {} not mapped", machineName, parName, parValue, couplingtype);
+                                break;
+                            default:
+                                log.error("macroblock {} - coupling parameter {} = {}; coupling type {} not supported", machineName, parName, parValue, couplingtype);
+                                throw new RuntimeException("macroblock " + machineName + " coupling parameter " + parName + " =  " + parValue + "; coupling type " + couplingtype + "not supported");
+                        }
+                        zmap.put(parName, newParValue);
+                        log.info("macroblock {} - coupling parameter: {} = {}  mapped to  {}", machineName, parName, parValue, newParValue);
+                    });
+            log.debug("Fixing macroblock's coupling parameters - id: {}, machine name: {} fixed macrobloc data: {}", eq.getCimId(), machineName, zm);
         }
 
         EurostagRecord eRecord = new EurostagRecord(zoneTypeName, zm);
@@ -1559,6 +1785,47 @@ public void dumpData(Internal inst, SimulatorInst simInst, DDBManager ddbmanager
         }
     }
 
+    protected HvdcLine getHvdcLineFromConverterStation(VscConverterStation vscStation) {
+        return  network.getHvdcLineStream()
+                .filter(hLine -> hLine.getConverterStation1().getId().equals(vscStation.getId()) || hLine.getConverterStation2().getId().equals(vscStation.getId()))
+                .findFirst()
+                .orElse(null);
+    }
+
+    protected boolean isPMode(HvdcConverterStation vscConv, HvdcLine hvdcLine) {
+        Objects.requireNonNull(vscConv);
+        Objects.requireNonNull(hvdcLine);
+        HvdcConverterStation side1Conv = hvdcLine.getConverterStation1();
+        HvdcConverterStation side2Conv = hvdcLine.getConverterStation2();
+        if ((hvdcLine.getConvertersMode().equals(HvdcLine.ConvertersMode.SIDE_1_RECTIFIER_SIDE_2_INVERTER))
+                && (vscConv.getId().equals(side1Conv.getId()))) {
+            return true;
+        }
+        if ((hvdcLine.getConvertersMode().equals(HvdcLine.ConvertersMode.SIDE_1_INVERTER_SIDE_2_RECTIFIER))
+                && (vscConv.getId().equals(side2Conv.getId()))) {
+            return true;
+        }
+        return false;
+    }
+
+    private boolean isMacroblockIncluded(VscConverterStation cvStation, HvdcLine hvdcLine, HashMap<String, Object> zm) {
+        Objects.requireNonNull(cvStation);
+        Objects.requireNonNull(hvdcLine);
+        Objects.requireNonNull(zm);
+        boolean isPmode = isPMode(cvStation, hvdcLine);
+        boolean metaP = zm.get("#PMODE") != null;
+        boolean metaV = zm.get("#VMODE") != null;
+        boolean retVal = (isPmode && metaP) || (!isPmode && metaV) || (!metaP && !metaV);
+        log.debug("VscConverterStation: {}, HvdcLine: {}, machine name: {}, macroblock name: {}, output macroblock: {}", cvStation.getId(), hvdcLine.getId(), zm.get("machine.name"), zm.get("macroblock.name"), retVal);
+        return retVal;
+    }
+
+    private boolean isMacroblockIncluded(VscConverterStation cvStation, HashMap<String, Object> zm) {
+        Objects.requireNonNull(cvStation);
+        Objects.requireNonNull(zm);
+        return isMacroblockIncluded(cvStation, getHvdcLineFromConverterStation(cvStation), zm);
+    }
+
     // Dump data without DDB parameters
     public void dumpDataAutomatons(SimulatorInst eurostagSim, DDBManager ddbmanager,
             PrintStream dtaOutStream, Map<String, String> iidm2eurostagId) throws ParseException, IOException {
diff --git a/iidm-ddb/iidm-ddb-eurostag-import-export/src/main/java/eu/itesla_project/iidm/ddb/eurostag_imp_exp/DtaParser.java b/iidm-ddb/iidm-ddb-eurostag-import-export/src/main/java/eu/itesla_project/iidm/ddb/eurostag_imp_exp/DtaParser.java
index a219687f..0ed4a3a9 100644
--- a/iidm-ddb/iidm-ddb-eurostag-import-export/src/main/java/eu/itesla_project/iidm/ddb/eurostag_imp_exp/DtaParser.java
+++ b/iidm-ddb/iidm-ddb-eurostag-import-export/src/main/java/eu/itesla_project/iidm/ddb/eurostag_imp_exp/DtaParser.java
@@ -137,6 +137,16 @@ private DtaParser(final String name) {
             "TerminalVoltage", "KG", "SCL", "SLOPE", "VPCC", "SETMODE", "MODE", "BSVC", "ZERO", "BMAX", "BTCR", "MSCON", "MSRON"
         });
 
+        componentsVariablesNames.put("M50", new String[]{
+            "machine.type, type.fortescue, XMACOUP, fnum1, fnum2, falpha",
+            "machine.name,connection.node.name,TFIL,PP,PQ,RP,RPX,SN"
+        });
+
+        componentsInterfaceVariablesNames.put("M50", new String[]{
+            "TerminalVoltage", "UDC", "UDCA", "UDCB", "UREF"
+        });
+
+
         componentsVariablesNames.put("MA", new String[]{
             "keyword",
             "ma.name,equipment.type,equipment.name"
@@ -242,6 +252,11 @@ private DtaParser(final String name) {
             "(A8, 1X, A8, 1X, A1, 17X, F8, 1X, F8, 19X, F8, F8, 1X, F8, 1X, F8, 1X, F8)"
         });
 
+        componentsDescriptors.put("M50", new String[]{
+            "(A3, A1, 1X, A1, 7X, F8, 1X, F8, 1X, A8)",
+            "(A8, 1X, A8, 3X, F8, 8X, F8, 1X, F8, 1X, F8, 1X, F8, 1X, F8)"
+        });
+
         componentsDescriptors.put("MA", new String[]{
             "(A2)",
             "(A8, 1X, A2, 1X, A8)"
@@ -387,6 +402,7 @@ public static void dumpZone(EurostagRecord zone, PrintStream out) throws ParseEx
             case "BAT":
             case "MA":
             case "A33_ACMC":
+            case "M50":
                 int rcount = 1;
                 String[] recordsFormatting = componentsDescriptors.get(zone.typeName);
                 for (String string : recordsFormatting) {