fex_lineflows.m

一个较好的MATLAB潮流程序

function [P_s,Q_s,P_r,Q_r,Is,Ir] = fex_lineflows
% FEX_LINEFLOWS -> called by FEX_ABCD
% compute line flows
%
% Author:  Alberto Del Rosso
% Date:    June 2004
% Update:
% Version: preliminary version
% E-mail:  [e-mail]
% 
% I M P O R T A N T   N O T E
% ===========================
% This external function is not part of the original PSAT software
% package although it uses many of PSAT functions. It has not been
% approved yet by Dr. Federico Milano to be distributed along with
% PSAT files.

global Fig Settings Snapshot Hdl
global Bus File DAE Theme
global SW PV PQ Fault Mn Ltc Syn
global Varout Breaker Line Path clpsat

jay=sqrt(-1);

if Line.n
  tps = Line.con(:,11).*exp(jay*Line.con(:,12)*pi/180);
  VV = DAE.V.*exp(jay*DAE.a);
  r = Line.con(:,8);
  rx = Line.con(:,9);
  chrg = Line.con(:,10)/2;
  %if strcmp(checkshunt,'on')
  %  chrg1 = chrg - jay*Shunt.g(Line.from) + Shunt.b(Line.from);
  %  chrg2 = chrg - jay*Shunt.g(Line.to) + Shunt.b(Line.to);
  %else
  chrg1 = chrg;
  chrg2 = chrg;
  %end
  z = r + jay*rx;
  y = ones(Line.n,1)./z;
  MW_s = VV(Line.from).* ...
         conj((VV(Line.from) - tps.*VV(Line.to)).*y ...
              + VV(Line.from).*(jay*chrg1))./(tps.*conj(tps));
  P_s = real(MW_s); % active power sent out by from_bus to to_bus
  Q_s = imag(MW_s); % reactive power sent out by from_bus to to_bus
  MW_r = VV(Line.to).* ...
         conj((VV(Line.to) - VV(Line.from)./tps).*y + ...
              VV(Line.to).*(jay*chrg2));
  P_r = real(MW_r); % active power received by to_bus from from_bus
  Q_r = imag(MW_r); % reactive power received by to_bus from from_bus
  from_bus = Line.from;
  to_bus = Line.to;
  % Current
  Ss = abs(MW_s);
  Sr = abs(MW_r);
  Is = Ss./DAE.V(Line.from);
  Ir = Sr./DAE.V(Line.to);
end