MAKEBDC Builds the B matrices and phase shift injections for DC power flow. [BBUS, BF, PBUSINJ, PFINJ] = MAKEBDC(BASEMVA, BUS, BRANCH) returns the B matrices and phase shift injection vectors needed for a DC power flow. The bus real power injections are related to bus voltage angles by P = BBUS * Va + PBUSINJ The real power flows at the from end the lines are related to the bus voltage angles by Pf = BF * Va + PFINJ Does appropriate conversions to p.u. Example: [Bbus, Bf, Pbusinj, Pfinj] = makeBdc(baseMVA, bus, branch); See also DCPF.
0001 function [Bbus, Bf, Pbusinj, Pfinj] = makeBdc(baseMVA, bus, branch) 0002 %MAKEBDC Builds the B matrices and phase shift injections for DC power flow. 0003 % [BBUS, BF, PBUSINJ, PFINJ] = MAKEBDC(BASEMVA, BUS, BRANCH) returns the 0004 % B matrices and phase shift injection vectors needed for a DC power flow. 0005 % The bus real power injections are related to bus voltage angles by 0006 % P = BBUS * Va + PBUSINJ 0007 % The real power flows at the from end the lines are related to the bus 0008 % voltage angles by 0009 % Pf = BF * Va + PFINJ 0010 % Does appropriate conversions to p.u. 0011 % 0012 % Example: 0013 % [Bbus, Bf, Pbusinj, Pfinj] = makeBdc(baseMVA, bus, branch); 0014 % 0015 % See also DCPF. 0016 0017 % MATPOWER 0018 % $Id: makeBdc.m 1635 2010-04-26 19:45:26Z ray $ 0019 % by Carlos E. Murillo-Sanchez, PSERC Cornell & Universidad Autonoma de Manizales 0020 % and Ray Zimmerman, PSERC Cornell 0021 % Copyright (c) 1996-2010 by Power System Engineering Research Center (PSERC) 0022 % 0023 % This file is part of MATPOWER. 0024 % See http://www.pserc.cornell.edu/matpower/ for more info. 0025 % 0026 % MATPOWER is free software: you can redistribute it and/or modify 0027 % it under the terms of the GNU General Public License as published 0028 % by the Free Software Foundation, either version 3 of the License, 0029 % or (at your option) any later version. 0030 % 0031 % MATPOWER is distributed in the hope that it will be useful, 0032 % but WITHOUT ANY WARRANTY; without even the implied warranty of 0033 % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 0034 % GNU General Public License for more details. 0035 % 0036 % You should have received a copy of the GNU General Public License 0037 % along with MATPOWER. If not, see <http://www.gnu.org/licenses/>. 0038 % 0039 % Additional permission under GNU GPL version 3 section 7 0040 % 0041 % If you modify MATPOWER, or any covered work, to interface with 0042 % other modules (such as MATLAB code and MEX-files) available in a 0043 % MATLAB(R) or comparable environment containing parts covered 0044 % under other licensing terms, the licensors of MATPOWER grant 0045 % you additional permission to convey the resulting work. 0046 0047 %% constants 0048 nb = size(bus, 1); %% number of buses 0049 nl = size(branch, 1); %% number of lines 0050 0051 %% define named indices into bus, branch matrices 0052 [PQ, PV, REF, NONE, BUS_I, BUS_TYPE, PD, QD, GS, BS, BUS_AREA, VM, ... 0053 VA, BASE_KV, ZONE, VMAX, VMIN, LAM_P, LAM_Q, MU_VMAX, MU_VMIN] = idx_bus; 0054 [F_BUS, T_BUS, BR_R, BR_X, BR_B, RATE_A, RATE_B, RATE_C, ... 0055 TAP, SHIFT, BR_STATUS, PF, QF, PT, QT, MU_SF, MU_ST, ... 0056 ANGMIN, ANGMAX, MU_ANGMIN, MU_ANGMAX] = idx_brch; 0057 0058 %% check that bus numbers are equal to indices to bus (one set of bus numbers) 0059 if any(bus(:, BUS_I) ~= (1:nb)') 0060 error('makeBdc: buses must be numbered consecutively in bus matrix') 0061 end 0062 0063 %% for each branch, compute the elements of the branch B matrix and the phase 0064 %% shift "quiescent" injections, where 0065 %% 0066 %% | Pf | | Bff Bft | | Vaf | | Pfinj | 0067 %% | | = | | * | | + | | 0068 %% | Pt | | Btf Btt | | Vat | | Ptinj | 0069 %% 0070 stat = branch(:, BR_STATUS); %% ones at in-service branches 0071 b = stat ./ branch(:, BR_X); %% series susceptance 0072 tap = ones(nl, 1); %% default tap ratio = 1 0073 i = find(branch(:, TAP)); %% indices of non-zero tap ratios 0074 tap(i) = branch(i, TAP); %% assign non-zero tap ratios 0075 b = b ./ tap; 0076 0077 %% build connection matrix Cft = Cf - Ct for line and from - to buses 0078 f = branch(:, F_BUS); %% list of "from" buses 0079 t = branch(:, T_BUS); %% list of "to" buses 0080 i = [(1:nl)'; (1:nl)']; %% double set of row indices 0081 Cft = sparse(i, [f;t], [ones(nl, 1); -ones(nl, 1)], nl, nb); %% connection matrix 0082 0083 %% build Bf such that Bf * Va is the vector of real branch powers injected 0084 %% at each branch's "from" bus 0085 Bf = sparse(i, [f; t], [b; -b]); % = spdiags(b, 0, nl, nl) * Cft; 0086 0087 %% build Bbus 0088 Bbus = Cft' * Bf; 0089 0090 %% build phase shift injection vectors 0091 Pfinj = b .* (-branch(:, SHIFT) * pi/180); %% injected at the from bus ... 0092 % Ptinj = -Pfinj; %% ... and extracted at the to bus 0093 Pbusinj = Cft' * Pfinj; %% Pbusinj = Cf * Pfinj + Ct * Ptinj;