% The function iprime = Gllshort(t, i) defines the differential
% equations of the synchronous machine during a
% phase-phase fault. The function returns the state derivatives
% of the current.
%current vector [-id,-iq,-i0,iF,iD,iQ]
% Copyright (c) 1998 H. Saadat,Modified by Jiang Qirong
function iprime =Gllshort(t,i)
f=50.; w=2.*pi*f;
d=0.; d=d*pi/180.; theta=w*t+d;
% Parameters of a 500 MVA, 30 kV Synchronous Machine
Ld = 0.0072; Lq = 0.0070; L0=0.0010; LF = 2.500; LD = 0.0068; LQ = 0.0016;
MF = 0.100; MD = 0.0054; MQ = 0.0026; MR = 0.1250;
r = 0.002; rF = 0.4000; rD = 0.015; rQ = 0.0150;
VF = 400; % dc field voltage
V = [0; 0; 0; VF; 0; 0]; % Voltage column vector
K=3/2.; RT2=sqrt(2.0);
R=[r 0 0 0 0 0
0 r 0 0 0 0
0 0 r 0 0 0
0 0 0 rF 0 0
0 0 0 0 rD 0
0 0 0 0 0 rQ];
L=[Ld 0 0 MF MD 0
0 Lq 0 0 0 MQ
0 0 L0 0 0 0
K*MF 0 0 LF MR 0
K*MD 0 0 MR LD 0
0 K*MQ 0 0 0 LQ];
WW=[0 -w 0 0 0 0
w 0 0 0 0 0
0 0 0 0 0 0
0 0 0 0 0 0
0 0 0 0 0 0
0 0 0 0 0 0];
Li=inv(L);
iprime=Li*V - Li*(WW*L+R)*i;
%%文件2－lecture21_22.m
fprintf('\
Wait simulation is in process. \
')
VF = 400; rF = 0.4; iF0 = VF/rF;
f = 50; w = 2.*pi*f; pi2=2.*pi/3;
d = 0; d = d*pi/180;
t0 = 0 ; tfinal = 0.80;
i0 = [0; 0; 0; iF0; 0; 0;]; % Initial currents
%[t,i] = ode45('Gllshort', t0, tfinal, i0); % use for MATLAB 4
tspan = [t0, tfinal]; % use for MATLAB 5
[t,i] = ode45('Gllshort', tspan, i0); % use for MATLAB 5
% id,iq,i0 = Armature current iF=Field current
id=i(:,1); iq=i(:,2);i0=(:,3) iF=i(:,4); iD=(:,5); iQ=(:,6)
%current dq0 to current abc
nn=length(id);
for kk=1:nn,
tt=t(kk);thetaa=w*tt;thetab=thetaa-pi2;thetac=thetaa+pi2;
ia(kk)=cos(thetaa)*id(kk)-sin(thetaa)*iq(kk)+i0(kk);
ib(kk)=cos(thetab)*id(kk)-sin(thetab)*iq(kk)+i0(kk);
ic(kk)=cos(thetac)*id(kk)-sin(thetac)*iq(kk)+i0(kk);
end
figure(1), plot(t,ia), xlabel('t, sec'), ylabel('ia, A'), grid
title(['three phase short circuit ia, ','delta = ', num2str(d)])
figure(2), plot(t,iF), xlabel('t, sec'
), ylabel('iF, A'), grid
title(['Line-line short circuit iF, ','delta = ',num2str(d)])下载本文
