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 % Copyright (c) 1996-2015 by Power System Engineering Research Center (PSERC) 0019 % by Carlos E. Murillo-Sanchez, PSERC Cornell & Universidad Autonoma de Manizales 0020 % and Ray Zimmerman, PSERC Cornell 0021 % 0022 % $Id: makeBdc.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 %% define named indices into bus, branch matrices 0033 [PQ, PV, REF, NONE, BUS_I, BUS_TYPE, PD, QD, GS, BS, BUS_AREA, VM, ... 0034 VA, BASE_KV, ZONE, VMAX, VMIN, LAM_P, LAM_Q, MU_VMAX, MU_VMIN] = idx_bus; 0035 [F_BUS, T_BUS, BR_R, BR_X, BR_B, RATE_A, RATE_B, RATE_C, ... 0036 TAP, SHIFT, BR_STATUS, PF, QF, PT, QT, MU_SF, MU_ST, ... 0037 ANGMIN, ANGMAX, MU_ANGMIN, MU_ANGMAX] = idx_brch; 0038 0039 %% check that bus numbers are equal to indices to bus (one set of bus numbers) 0040 if any(bus(:, BUS_I) ~= (1:nb)') 0041 error('makeBdc: buses must be numbered consecutively in bus matrix') 0042 end 0043 0044 %% for each branch, compute the elements of the branch B matrix and the phase 0045 %% shift "quiescent" injections, where 0046 %% 0047 %% | Pf | | Bff Bft | | Vaf | | Pfinj | 0048 %% | | = | | * | | + | | 0049 %% | Pt | | Btf Btt | | Vat | | Ptinj | 0050 %% 0051 stat = branch(:, BR_STATUS); %% ones at in-service branches 0052 b = stat ./ branch(:, BR_X); %% series susceptance 0053 tap = ones(nl, 1); %% default tap ratio = 1 0054 i = find(branch(:, TAP)); %% indices of non-zero tap ratios 0055 tap(i) = branch(i, TAP); %% assign non-zero tap ratios 0056 b = b ./ tap; 0057 0058 %% build connection matrix Cft = Cf - Ct for line and from - to buses 0059 f = branch(:, F_BUS); %% list of "from" buses 0060 t = branch(:, T_BUS); %% list of "to" buses 0061 i = [(1:nl)'; (1:nl)']; %% double set of row indices 0062 Cft = sparse(i, [f;t], [ones(nl, 1); -ones(nl, 1)], nl, nb); %% connection matrix 0063 0064 %% build Bf such that Bf * Va is the vector of real branch powers injected 0065 %% at each branch's "from" bus 0066 Bf = sparse(i, [f; t], [b; -b]); % = spdiags(b, 0, nl, nl) * Cft; 0067 0068 %% build Bbus 0069 Bbus = Cft' * Bf; 0070 0071 %% build phase shift injection vectors 0072 Pfinj = b .* (-branch(:, SHIFT) * pi/180); %% injected at the from bus ... 0073 % Ptinj = -Pfinj; %% ... and extracted at the to bus 0074 Pbusinj = Cft' * Pfinj; %% Pbusinj = Cf * Pfinj + Ct * Ptinj;