makeJac

MAKEJAC  Forms the power flow Jacobian.
   J = MAKEJAC(MPC)
   J = MAKEJAC(MPC, FULLJAC)
   J = MAKEJAC(BASEMVA, BUS, BRANCH, GEN)
   J = MAKEJAC(BASEMVA, BUS, BRANCH, GEN, FULLJAC)
   [J, YBUS, YF, YT] = MAKEJAC(MPC)

   Returns the power flow Jacobian and, optionally, the system admittance
   matrices. Inputs can be a MATPOWER case struct or individual BASEMVA,
   BUS, BRANCH and GEN values. Bus numbers must be consecutive beginning
   at 1 (i.e. internal ordering). If the FULLJAC argument is present and
   true, it returns the full Jacobian (sensitivities of all bus injections
   w.r.t all voltage angles/magnitudes) as opposed to the reduced version
   used in the Newton power flow updates.

   Note: This function builds the Jacobian from scratch, rebuilding the
         YBUS matrix in the process. You probably don't want to use this
         in performance critical code.

   See also MAKEYBUS, EXT2INT

0001 function [J, Ybus, Yf, Yt] = makeJac(baseMVA, bus, branch, gen, fullJac)
0002 %MAKEJAC  Forms the power flow Jacobian.
0003 %   J = MAKEJAC(MPC)
0004 %   J = MAKEJAC(MPC, FULLJAC)
0005 %   J = MAKEJAC(BASEMVA, BUS, BRANCH, GEN)
0006 %   J = MAKEJAC(BASEMVA, BUS, BRANCH, GEN, FULLJAC)
0007 %   [J, YBUS, YF, YT] = MAKEJAC(MPC)
0008 %
0009 %   Returns the power flow Jacobian and, optionally, the system admittance
0010 %   matrices. Inputs can be a MATPOWER case struct or individual BASEMVA,
0011 %   BUS, BRANCH and GEN values. Bus numbers must be consecutive beginning
0012 %   at 1 (i.e. internal ordering). If the FULLJAC argument is present and
0013 %   true, it returns the full Jacobian (sensitivities of all bus injections
0014 %   w.r.t all voltage angles/magnitudes) as opposed to the reduced version
0015 %   used in the Newton power flow updates.
0016 %
0017 %   Note: This function builds the Jacobian from scratch, rebuilding the
0018 %         YBUS matrix in the process. You probably don't want to use this
0019 %         in performance critical code.
0020 %
0021 %   See also MAKEYBUS, EXT2INT
0022 
0023 %   MATPOWER
0024 %   Copyright (c) 1996-2016, Power Systems Engineering Research Center (PSERC)
0025 %   by Ray Zimmerman, PSERC Cornell
0026 %
0027 %   This file is part of MATPOWER.
0028 %   Covered by the 3-clause BSD License (see LICENSE file for details).
0029 %   See http://www.pserc.cornell.edu/matpower/ for more info.
0030 
0031 if nargin < 4
0032     mpc     = baseMVA;
0033     if nargin > 1
0034         fullJac = bus;
0035     else
0036         fullJac = 0;
0037     end
0038     baseMVA = mpc.baseMVA;
0039     bus     = mpc.bus;
0040     branch  = mpc.branch;
0041     gen     = mpc.gen;
0042 elseif nargin < 5
0043     fullJac = 0;
0044 end
0045 
0046 %% define named indices into bus, gen, branch matrices
0047 [PQ, PV, REF, NONE, BUS_I, BUS_TYPE, PD, QD, GS, BS, BUS_AREA, VM, ...
0048     VA, BASE_KV, ZONE, VMAX, VMIN, LAM_P, LAM_Q, MU_VMAX, MU_VMIN] = idx_bus;
0049 [GEN_BUS, PG, QG, QMAX, QMIN, VG, MBASE, GEN_STATUS, PMAX, PMIN, ...
0050     MU_PMAX, MU_PMIN, MU_QMAX, MU_QMIN, PC1, PC2, QC1MIN, QC1MAX, ...
0051     QC2MIN, QC2MAX, RAMP_AGC, RAMP_10, RAMP_30, RAMP_Q, APF] = idx_gen;
0052 
0053 %% build Ybus
0054 [Ybus, Yf, Yt] = makeYbus(baseMVA, bus, branch);
0055 
0056 %% extract voltage
0057 V = bus(:, VM) .* exp(sqrt(-1) * pi/180 * bus(:, VA));
0058 on = find(gen(:, GEN_STATUS) > 0);      %% which generators are on?
0059 gbus = gen(on, GEN_BUS);                %% what buses are they at?
0060 V(gbus) = gen(on, VG) ./ abs(V(gbus)).* V(gbus);
0061 
0062 %% build Jacobian
0063 [dSbus_dVm, dSbus_dVa] = dSbus_dV(Ybus, V);
0064 if fullJac
0065     j11 = real(dSbus_dVa);
0066     j12 = real(dSbus_dVm);
0067     j21 = imag(dSbus_dVa);
0068     j22 = imag(dSbus_dVm);
0069 else
0070     %% get bus index lists of each type of bus
0071     [ref, pv, pq] = bustypes(bus, gen);
0072 
0073     j11 = real(dSbus_dVa([pv; pq], [pv; pq]));
0074     j12 = real(dSbus_dVm([pv; pq], pq));
0075     j21 = imag(dSbus_dVa(pq, [pv; pq]));
0076     j22 = imag(dSbus_dVm(pq, pq));
0077 end
0078 
0079 J = [   j11 j12;
0080         j21 j22;    ];