makeB

MAKEB   Builds the FDPF matrices, B prime and B double prime.
   [BP, BPP] = MAKEB(BASEMVA, BUS, BRANCH, ALG) returns the two
   matrices B prime and B double prime used in the fast decoupled power
   flow. Does appropriate conversions to p.u. ALG is either 'FDXB' or
   'FDBX', the corresponding value of MPOPT.pf.alg option specifying the
   power flow algorithm.

   Note: For backward compatibility, ALG can also take on a value of
   2 or 3, corresponding to values of the old PF_ALG option. This usage
   is deprecated and will be removed in a future version.

   Example:
       [Bp, Bpp] = makeB(baseMVA, bus, branch, 'FDXB');

   See also FDPF.

0001 function [Bp, Bpp] = makeB(baseMVA, bus, branch, alg)
0002 %MAKEB   Builds the FDPF matrices, B prime and B double prime.
0003 %   [BP, BPP] = MAKEB(BASEMVA, BUS, BRANCH, ALG) returns the two
0004 %   matrices B prime and B double prime used in the fast decoupled power
0005 %   flow. Does appropriate conversions to p.u. ALG is either 'FDXB' or
0006 %   'FDBX', the corresponding value of MPOPT.pf.alg option specifying the
0007 %   power flow algorithm.
0008 %
0009 %   Note: For backward compatibility, ALG can also take on a value of
0010 %   2 or 3, corresponding to values of the old PF_ALG option. This usage
0011 %   is deprecated and will be removed in a future version.
0012 %
0013 %   Example:
0014 %       [Bp, Bpp] = makeB(baseMVA, bus, branch, 'FDXB');
0015 %
0016 %   See also FDPF.
0017 
0018 %   MATPOWER
0019 %   Copyright (c) 1996-2015 by Power System Engineering Research Center (PSERC)
0020 %   by Ray Zimmerman, PSERC Cornell
0021 %
0022 %   $Id: makeB.m 2644 2015-03-11 19:34:22Z ray $
0023 %
0024 %   This file is part of MATPOWER.
0025 %   Covered by the 3-clause BSD License (see LICENSE file for details).
0026 %   See http://www.pserc.cornell.edu/matpower/ for more info.
0027 
0028 %% constants
0029 nb = size(bus, 1);          %% number of buses
0030 nl = size(branch, 1);       %% number of lines
0031 
0032 %% backward compatiblility (deprecated)
0033 if ~ischar(alg)
0034     if alg == 2
0035         alg = 'FDXB';
0036     elseif alg == 3
0037         alg = 'FDBX';
0038     end
0039 end
0040 
0041 %% check for valid ALG value
0042 alg = upper(alg);
0043 if ~strcmp(alg, 'FDXB') && ~strcmp(alg, 'FDBX')
0044     error('makeB: ''%s'' is not a valid value for ALG', alg);
0045 end
0046 
0047 %% define named indices into bus, branch matrices
0048 [PQ, PV, REF, NONE, BUS_I, BUS_TYPE, PD, QD, GS, BS, BUS_AREA, VM, ...
0049     VA, BASE_KV, ZONE, VMAX, VMIN, LAM_P, LAM_Q, MU_VMAX, MU_VMIN] = idx_bus;
0050 [F_BUS, T_BUS, BR_R, BR_X, BR_B, RATE_A, RATE_B, RATE_C, ...
0051     TAP, SHIFT, BR_STATUS, PF, QF, PT, QT, MU_SF, MU_ST, ...
0052     ANGMIN, ANGMAX, MU_ANGMIN, MU_ANGMAX] = idx_brch;
0053 
0054 %%-----  form Bp (B prime)  -----
0055 temp_branch = branch;                       %% modify a copy of branch
0056 temp_bus = bus;                             %% modify a copy of bus
0057 temp_bus(:, BS) = zeros(nb, 1);             %% zero out shunts at buses
0058 temp_branch(:, BR_B) = zeros(nl, 1);        %% zero out line charging shunts
0059 temp_branch(:, TAP) = ones(nl, 1);          %% cancel out taps
0060 if strcmp(alg, 'FDXB')                      %% if XB method
0061     temp_branch(:, BR_R) = zeros(nl, 1);        %% zero out line resistance
0062 end
0063 Bp = -imag( makeYbus(baseMVA, temp_bus, temp_branch) );
0064 
0065 %%-----  form Bpp (B double prime)  -----
0066 if nargout == 2
0067     temp_branch = branch;                       %% modify a copy of branch
0068     temp_branch(:, SHIFT) = zeros(nl, 1);       %% zero out phase shifters
0069     if strcmp(alg, 'FDBX')                      %% if BX method
0070         temp_branch(:, BR_R) = zeros(nl, 1);        %% zero out line resistance
0071     end
0072     Bpp = -imag( makeYbus(baseMVA, bus, temp_branch) );
0073 end