Merge pull request #153 from openego/fix/#152

Fix/#152

doc/whatsnew/v0-0-10.rst

@@ -5,3 +5,8 @@ Release date: <month> <day>, <year>
 
 Changes
 -------
+* 
+
+Bug fixes
+----------
+* Corrected calculation of current from pypsa power flow results (PR #153 `#153 <https://github.com/openego/eDisGo/pull/153>`_).

edisgo/flex_opt/check_tech_constraints.py

@@ -345,8 +345,8 @@ def mv_voltage_deviation(network, voltage_levels='mv_lv'):
 
     Notes
     -----
-    Over-voltage is determined based on allowed voltage deviations defined in
-    the config file 'config_grid_expansion' in section
+    Voltage issues are determined based on allowed voltage deviations defined
+    in the config file 'config_grid_expansion' in section
     'grid_expansion_allowed_voltage_deviations'.
 
     """
@@ -445,8 +445,8 @@ def lv_voltage_deviation(network, mode=None, voltage_levels='mv_lv'):
 
     Notes
     -----
-    Over-voltage is determined based on allowed voltage deviations defined in
-    the config file 'config_grid_expansion' in section
+    Voltage issues are determined based on allowed voltage deviations defined
+    in the config file 'config_grid_expansion' in section
     'grid_expansion_allowed_voltage_deviations'.
 
     """

edisgo/grid/network.py

@@ -118,7 +118,7 @@ def plot_mv_line_loading(self, **kwargs):
                 timestep=kwargs.get('timestep', None),
                 line_color='loading',
                 node_color=kwargs.get('node_color', None),
-                line_load=self.network.results.s_res(),
+                line_load=self.network.results.i_res,
                 filename=kwargs.get('filename', None),
                 arrows=kwargs.get('arrows', None),
                 grid_district_geom=kwargs.get('grid_district_geom', True),
@@ -206,25 +206,34 @@ def histogram_voltage(self, timestep=None, title=True, **kwargs):
         """
         Plots histogram of voltages.
 
-        For more information see :func:`edisgo.tools.plots.histogram`.
+        For more information on the histogram plot and possible configurations
+        see :func:`edisgo.tools.plots.histogram`.
 
         Parameters
         ----------
-        timestep : :pandas:`pandas.Timestamp<timestamp>` or None, optional
-            Specifies time step histogram is plotted for. If timestep is None
+        timestep : :pandas:`pandas.Timestamp<timestamp>` or list(:pandas:`pandas.Timestamp<timestamp>`) or None, optional
+            Specifies time steps histogram is plotted for. If timestep is None
             all time steps voltages are calculated for are used. Default: None.
         title : :obj:`str` or :obj:`bool`, optional
             Title for plot. If True title is auto generated. If False plot has
             no title. If :obj:`str`, the provided title is used. Default: True.
 
         """
         data = self.network.results.v_res()
+
+        if timestep is None:
+            timestep = data.index
+        # check if timesteps is array-like, otherwise convert to list
+        if not hasattr(timestep, "__len__"):
+            timestep = [timestep]
+
         if title is True:
-            if timestep is not None:
-                title = "Voltage histogram for time step {}".format(timestep)
+            if len(timestep) == 1:
+                title = "Voltage histogram for time step {}".format(
+                    timestep[0])
             else:
                 title = "Voltage histogram \nfor time steps {} to {}".format(
-                    data.index[0], data.index[-1])
+                    timestep[0], timestep[-1])
         elif title is False:
             title = None
         plots.histogram(data=data, title=title, timeindex=timestep, **kwargs)
@@ -234,15 +243,17 @@ def histogram_relative_line_load(self, timestep=None, title=True,
         """
         Plots histogram of relative line loads.
 
-        For more information see :func:`edisgo.tools.plots.histogram`.
+        For more information on how the relative line load is calculated see
+        :func:`edisgo.tools.tools.get_line_loading_from_network`.
+        For more information on the histogram plot and possible configurations
+        see :func:`edisgo.tools.plots.histogram`.
 
         Parameters
         ----------
-        Parameters
-        ----------
-        timestep : :pandas:`pandas.Timestamp<timestamp>` or None, optional
-            Specifies time step histogram is plotted for. If timestep is None
-            all time steps voltages are calculated for are used. Default: None.
+        timestep : :pandas:`pandas.Timestamp<timestamp>` or list(:pandas:`pandas.Timestamp<timestamp>`) or None, optional
+            Specifies time step(s) histogram is plotted for. If `timestep` is
+            None all time steps currents are calculated for are used.
+            Default: None.
         title : :obj:`str` or :obj:`bool`, optional
             Title for plot. If True title is auto generated. If False plot has
             no title. If :obj:`str`, the provided title is used. Default: True.
@@ -252,20 +263,6 @@ def histogram_relative_line_load(self, timestep=None, title=True,
             fallback option in case of wrong input. Default: 'mv_lv'
 
         """
-        residual_load = tools.get_residual_load_from_pypsa_network(
-            self.network.pypsa)
-        case = residual_load.apply(
-            lambda _: 'feedin_case' if _ < 0 else 'load_case')
-        if timestep is not None:
-            timeindex = [timestep]
-        else:
-            timeindex = self.network.results.s_res().index
-        load_factor = pd.DataFrame(
-            data={'s_nom': [float(self.network.config[
-                                      'grid_expansion_load_factors'][
-                                      'mv_{}_line'.format(case.loc[_])])
-                            for _ in timeindex]},
-            index=timeindex)
         if voltage_level == 'mv':
             lines = self.network.pypsa.lines.loc[
                 self.network.pypsa.lines.v_nom > 1]
@@ -274,24 +271,28 @@ def histogram_relative_line_load(self, timestep=None, title=True,
                 self.network.pypsa.lines.v_nom < 1]
         else:
             lines = self.network.pypsa.lines
-        s_res = self.network.results.s_res().loc[
-            timeindex, lines.index]
-        # get allowed line load
-        s_allowed = load_factor.dot(
-            self.network.pypsa.lines.s_nom.to_frame().T * 1e3)
-        # get line load from pf
-        data = s_res.divide(s_allowed)
+
+        rel_line_loading = tools.calculate_relative_line_load(
+            self.network.pypsa, self.network.config,
+            self.network.results.i_res, self.network.pypsa.lines.v_nom,
+            lines.index, timestep)
+
+        if timestep is None:
+            timestep = rel_line_loading.index
+        # check if timesteps is array-like, otherwise convert to list
+        if not hasattr(timestep, "__len__"):
+            timestep = [timestep]
 
         if title is True:
-            if timestep is not None:
+            if len(timestep) == 1:
                 title = "Relative line load histogram for time step {}".format(
-                    timestep)
+                    timestep[0])
             else:
                 title = "Relative line load histogram \nfor time steps " \
-                        "{} to {}".format(data.index[0], data.index[-1])
+                        "{} to {}".format(timestep[0], timestep[-1])
         elif title is False:
             title = None
-        plots.histogram(data=data, title=title, **kwargs)
+        plots.histogram(data=rel_line_loading, title=title, **kwargs)
 
 
 class EDisGo(EDisGoReimport):
@@ -2939,7 +2940,7 @@ def s_res(self, components=None):
 
     def v_res(self, nodes=None, level=None):
         """
-        Get resulting voltage level at node.
+        Get voltage results (in p.u.) from power flow analysis.
 
         Parameters
         ----------

edisgo/tools/plots.py

@@ -37,9 +37,9 @@ def histogram(data, **kwargs):
         Data to be plotted, e.g. voltage or current (`v_res` or `i_res` from
         :class:`edisgo.grid.network.Results`). Index of the dataframe must be
         a :pandas:`pandas.DatetimeIndex<datetimeindex>`.
-    timeindex : :pandas:`pandas.Timestamp<timestamp>` or None, optional
-        Specifies time step histogram is plotted for. If timeindex is None all
-        time steps provided in dataframe are used. Default: None.
+    timeindex : :pandas:`pandas.Timestamp<timestamp>` or list(:pandas:`pandas.Timestamp<timestamp>`) or None, optional
+        Specifies time steps histogram is plotted for. If timeindex is None all
+        time steps provided in `data` are used. Default: None.
     directory : :obj:`str` or None, optional
         Path to directory the plot is saved to. Is created if it does not
         exist. Default: None.
@@ -78,6 +78,12 @@ def histogram(data, **kwargs):
 
     """
     timeindex = kwargs.get('timeindex', None)
+    if timeindex is None:
+        timeindex = data.index
+    # check if timesteps is array-like, otherwise convert to list
+    if not hasattr(timeindex, "__len__"):
+        timeindex = [timeindex]
+
     directory = kwargs.get('directory', None)
     filename = kwargs.get('filename', None)
     title = kwargs.get('title', "")
@@ -102,10 +108,7 @@ def histogram(data, **kwargs):
     except:
         fig_size = standard_sizes['a5landscape']
 
-    if timeindex is not None:
-        plot_data = data.loc[timeindex, :]
-    else:
-        plot_data = data.T.stack()
+    plot_data = data.loc[timeindex, :].T.stack()
 
     if binwidth is not None:
         if x_limits is not None:
@@ -217,7 +220,7 @@ def mv_grid_topology(pypsa_network, configs, timestep=None,
         Time step to plot analysis results for. If `timestep` is None maximum
         line load and if given, maximum voltage deviation, is used. In that
         case arrows cannot be drawn. Default: None.
-    line_color : :obj:`str`
+    line_color : :obj:`str` or None
         Defines whereby to choose line colors (and implicitly size). Possible
         options are:
 
@@ -234,7 +237,7 @@ def mv_grid_topology(pypsa_network, configs, timestep=None,
           Lines are plotted in black. Is also the fallback option in case of
           wrong input.
 
-    node_color : :obj:`str`
+    node_color : :obj:`str` or None
         Defines whereby to choose node colors (and implicitly size). Possible
         options are:
 
@@ -251,13 +254,16 @@ def mv_grid_topology(pypsa_network, configs, timestep=None,
           Nodes are not plotted. Is also the fallback option in case of wrong
           input.
 
-    line_load : :pandas:`pandas.DataFrame<dataframe>`
+    line_load : :pandas:`pandas.DataFrame<dataframe>` or None
         Dataframe with current results from power flow analysis in A. Index of
         the dataframe is a :pandas:`pandas.DatetimeIndex<datetimeindex>`,
-        columns are the line representatives.
-    grid_expansion_costs : :pandas:`pandas.DataFrame<dataframe>`
+        columns are the line representatives. Only needs to be provided when
+        parameter `line_color` is set to 'loading'. Default: None.
+    grid_expansion_costs : :pandas:`pandas.DataFrame<dataframe>` or None
         Dataframe with grid expansion costs in kEUR. See `grid_expansion_costs`
-        in :class:`~.grid.network.Results` for more information.
+        in :class:`~.grid.network.Results` for more information. Only needs to
+        be provided when parameter `line_color` is set to 'expansion_costs'.
+        Default: None.
     filename : :obj:`str`
         Filename to save plot under. If not provided, figure is shown directly.
         Default: None.
@@ -266,12 +272,25 @@ def mv_grid_topology(pypsa_network, configs, timestep=None,
         only work when `line_color` option 'loading' is used and a time step
         is given.
         Default: False.
+    grid_district_geom : :obj:`Boolean`
+        If True grid district polygon is plotted in the background. This also
+        requires the geopandas package to be installed. Default: True.
+    background_map : :obj:`Boolean`
+        If True map is drawn in the background. This also requires the
+        contextily package to be installed. Default: True.
+    voltage : :pandas:`pandas.DataFrame<dataframe>`
+        Dataframe with voltage results from power flow analysis in p.u.. Index
+        of the dataframe is a :pandas:`pandas.DatetimeIndex<datetimeindex>`,
+        columns are the bus representatives. Only needs to be provided when
+        parameter `node_color` is set to 'voltage'. Default: None.
     limits_cb_lines : :obj:`tuple`
         Tuple with limits for colorbar of line color. First entry is the
-        minimum and second entry the maximum value. Default: None.
+        minimum and second entry the maximum value. Only needs to be provided
+        when parameter `line_color` is not None. Default: None.
     limits_cb_nodes : :obj:`tuple`
         Tuple with limits for colorbar of nodes. First entry is the
-        minimum and second entry the maximum value. Default: None.
+        minimum and second entry the maximum value. Only needs to be provided
+        when parameter `node_color` is not None. Default: None.
     xlim : :obj:`tuple`
         Limits of x-axis. Default: None.
     ylim : :obj:`tuple`
@@ -412,7 +431,7 @@ def nodes_by_costs(buses, grid_expansion_costs):
 
     # create pypsa network only containing MV buses and lines
     pypsa_plot = PyPSANetwork()
-    pypsa_plot.buses = pypsa_network.buses.loc[pypsa_network.buses.v_nom >= 10]
+    pypsa_plot.buses = pypsa_network.buses.loc[pypsa_network.buses.v_nom > 1]
     # filter buses of aggregated loads and generators
     pypsa_plot.buses = pypsa_plot.buses[
         ~pypsa_plot.buses.index.str.contains("agg")]
@@ -422,28 +441,9 @@ def nodes_by_costs(buses, grid_expansion_costs):
 
     # line colors
     if line_color == 'loading':
-        # calculate relative line loading
-        # get load factor
-        residual_load = tools.get_residual_load_from_pypsa_network(
-            pypsa_network)
-        case = residual_load.apply(
-                lambda _: 'feedin_case' if _ < 0 else 'load_case')
-        if timestep is not None:
-            timeindex = [timestep]
-        else:
-            timeindex = line_load.index
-        load_factor = pd.DataFrame(
-            data={'s_nom': [float(configs[
-                                      'grid_expansion_load_factors'][
-                                      'mv_{}_line'.format(case.loc[_])])
-                            for _ in timeindex]},
-            index=timeindex)
-        # get allowed line load
-        s_allowed = load_factor.dot(
-            pypsa_plot.lines.s_nom.to_frame().T * 1e3)
-        # get line load from pf
-        line_colors = line_load.loc[:, pypsa_plot.lines.index].divide(
-            s_allowed).max()
+        line_colors = tools.calculate_relative_line_load(
+            pypsa_network, configs, line_load, pypsa_network.lines.v_nom,
+            pypsa_plot.lines.index, timestep).max()
     elif line_color == 'expansion_costs':
         node_color = 'expansion_costs'
         line_costs = pypsa_plot.lines.join(

edisgo/tools/pypsa_io.py

@@ -556,10 +556,13 @@ def lv_to_pypsa(network):
 
         line['type'].append("")
         line['x'].append(
-            l['line'].type['L'] * omega / 1e3 * l['line'].length)
-        line['r'].append(l['line'].type['R'] * l['line'].length)
+            l['line'].type['L'] / l['line'].quantity * omega / 1e3 *
+            l['line'].length)
+        line['r'].append(l['line'].type['R'] / l['line'].quantity *
+                         l['line'].length)
         line['s_nom'].append(
-            sqrt(3) * l['line'].type['I_max_th'] * l['line'].type['U_n'] / 1e3)
+            sqrt(3) * l['line'].type['I_max_th'] * l['line'].type['U_n'] *
+            l['line'].quantity / 1e3)
         line['length'].append(l['line'].length)
 
     # create dataframe representing storages
@@ -1281,14 +1284,12 @@ def process_pfa_results(network, pypsa, timesteps):
                     list(lines_bus1.values()), :].copy()
     bus1_v_mag_pu.index = list(lines_bus1.keys())
 
-    line_voltage_avg = 0.5 * (bus0_v_mag_pu.loc[:, timesteps] +
-                              bus1_v_mag_pu.loc[:, timesteps])
+    # Get line current
+    network.results._i_res = np.hypot(
+        pypsa.lines_t['p0'], pypsa.lines_t['q0']).truediv(
+        pypsa.lines['v_nom'] * bus0_v_mag_pu.T,
+            axis='columns') / sqrt(3) * 1e3
 
-    # Get voltage levels at line (avg. of buses at both sides)
-    network.results._i_res = \
-        network.results.s_res()[pypsa.lines_t['q0'].columns].truediv(
-            pypsa.lines['v_nom'] * line_voltage_avg.T,
-            axis='columns') * sqrt(3)
     # process results at nodes
     generators_names = [repr(g) for g in network.mv_grid.generators]
     generators_mapping = {v: k for k, v in