Adding makeSg, makeSd and makeYsh functions.

pypf/makeSbus.py

@@ -5,11 +5,12 @@
 """Builds the vector of complex bus power injections.
 """
 
-from numpy import array, ones, flatnonzero as find
+from numpy import zeros, ones, flatnonzero as find
+import numpy as np
 from scipy.sparse import csr_matrix as sparse
 
 
-def makeSbus(baseMVA, bus, gen):
+def makeSbus(baseMVA, bus, load, gen):
     """Builds the vector of complex bus power injections.
 
     Returns the vector of complex bus power injections, that is, generation
@@ -19,18 +20,57 @@ def makeSbus(baseMVA, bus, gen):
 
     @author: Ray Zimmerman (PSERC Cornell)
     """
-    ## generator info
-    on = find(array(gen.status) > 0)      ## which generators are on?
-    gbus = array(gen.bus)[on]             ## what buses are they at?
-
-    ## form net complex bus power injection vector
-    nb = bus.n
-    ngon = on.shape[0]
-    ## connection matrix, element i, j is 1 if gen on(j) at bus i is ON
+    Sg = makeSg(bus.n, gen)
+    Sd = makeSd(bus.n, load)
+
+    # Form net complex bus power injection vector.
+    return (Sg - Sd) / baseMVA
+
+
+def makeSg(nb, gen):
+    on = find(gen.status > 0)
+    gbus = gen.bus[on]
+    ngon = len(on)
+    if ngon == 0:
+        return zeros(nb, dtype='complex')
+
+    # Connection matrix, element i, j is 1 if gen on(j) at bus i is ON.
     Cg = sparse((ones(ngon), (gbus, range(ngon))), (nb, ngon))
 
-    ## power injected by gens plus power injected by loads converted to p.u.
-    Sbus = ( Cg * (gen.Pg[on] + 1j * gen.Qg[on]) -
-             (bus.Pd + 1j * bus.Qd) ) / baseMVA
+    Pg = gen.pg[on]
+    Qg = gen.qg[on]
+    Sg = np.complex(Pg, Qg);
+
+    return Cg * Sg # power injected by generators
+
+
+def makeSd(nb, load):
+    on = find(load.status > 0)
+    ldbus = load.bus[on]
+    non = len(on)
+    if non == 0:
+        return zeros(nb, dtype='complex')
+
+    Cd = sparse((ones(non), (ldbus, range(non))), (nb, non))
+
+    Pd = load.Pd[on]
+    Qd = load.Qd[on]
+    Sd = np.complex(Pd, Qd)
+
+    return Cd * Sd
+
+
+def makeYsh(nb, shunt):
+    on = find(shunt.status > 0)
+    shbus = shunt.bus[on]
+    non = len(on)
+    if non == 0:
+        return zeros(nb, dtype='complex')
+
+    Csh = sparse((ones(non), (shbus, range(non))), (nb, non))
+
+    Gs = shunt.Gs[on]
+    Bs = shunt.Bs[on]
+    Ysh = np.complex(Gs, Bs)
 
-    return Sbus
+    return Csh * Ysh

pypf/makeYbus.py

@@ -7,9 +7,10 @@
 
 from numpy import ones, conj, nonzero, exp, pi, r_
 from scipy.sparse import csr_matrix
+from makeSbus import makeYsh
 
 
-def makeYbus(baseMVA, bus, branch):
+def makeYbus(baseMVA, bus, shunt, branch):
     """Builds the bus admittance matrix and branch admittance matrices.
 
     Returns the full bus admittance matrix (i.e. for all buses) and the
@@ -55,7 +56,7 @@ def makeYbus(baseMVA, bus, branch):
     ## then Psh - j Qsh = V * conj(Ysh * V) = conj(Ysh) = Gs - j Bs,
     ## i.e. Ysh = Psh + j Qsh, so ...
     ## vector of shunt admittances
-    Ysh = (bus.Gs + 1j * bus.Bs) / baseMVA
+    Ysh = makeYsh(nb, shunt) / baseMVA
 
     ## build connection matrices
     f = branch.f_bus                           ## list of "from" buses