MATLAB中绘图的应用

%%%三相同步发电机实验%%%

clc;
IF=[946.5 805.5 704.1 603.4 503.1 402.2 299.3 262.2 0];
U=[261.3 244.4 231.5 211.7 188 160.2 127.6 115.4 16.2];
IF1=0:10:1000;
%%%%%%%%%%%%%%%%%%%%%%%%%%%
subplot(2,2,1);
U1=interp1(IF,U,IF1,'cubic');
plot(IF1,U1,IF,U,'*');
grid on;
axis([0,1000,0,300]);
title('n=1500rpm 空载特性 ');
 xlabel('IF  mA');
 ylabel('U1  V');
 text(900,350,'030820121 钱强  林忠麟 张鑫');
 subplot(2,2,2);
%%%%%%%%%%%%%%%%%%%
If=[669 500 401 354 304];
I=[419 328 272 244 213];
If1=0:1:700;
Ik=interp1(If,I,If1,'cubic');
plot(If1,Ik,If,I,'*');
grid on;
axis([0,700,0,500]);
% T2a=interp1(P2,T2,P2a,'spline');
% Tema=interp1(P2,Tem,P2a,'spline');
% plot(P2a,T2a,':',P2a,Tema,'-',P2,T2,'*',P2,Tem,'o');
% grid on;
% axis([0,220,0,1.5]);
 title('短路特性');
% legend('T2 负载转矩','Tem 电磁转矩');
 xlabel('If  mA');
 ylabel('Ik  mA'  );               %%同步发电机的短路特性。
 for i=1:length(If1)-1
    k(i)=(Ik(i+1)-Ik(i))/(If1(i+1)-If1(i));
 end
cc=mean(k)

% %%%%%%%%%%%%%%%%%%%%%%%%
%  I=[1.662 1.516 1.412 1.340 1.240 1.100 0.902 0.66];
% Ia=interp1(P2,I,P2a,'cubic');
subplot(2,2,3);
I=[ 172 204.9 278.5 398.8 505.2];
U=[ 267.5 264.2 261.6 247.1 215.6];
I1=0:1:550;
U1=interp1(I,U,I1,'spline');
 plot(I1,U1,I,U,'*');
 axis([160,550,200,270]);
 grid on;
xlabel('I mA');
 ylabel('U V');
 title('n=1500rpm  If=1.1A 纯电阻负载特性');
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% P1=I.*220
% effect=P2./P1
% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 subplot(2,2,4);
 VIF=[1584 1345 1201 1010 867 712 650 582 529 453 394 326 264];
 VI=[437 346 284 196.8 127.9 50.52 20.27 24.63 49.8 90 122.8 165.6 195.1];
 vif=0:1:1700;
 
 vi=interp1(VIF,VI,vif,'s');
plot(VIF,VI,'*',vif,vi);
 grid on;
 axis([200,1700,0,500]);
 xlabel('If  mA');
 ylabel(' I  mA ');
 title('U=127V ,n= 1500rpm  P2 =0   V形曲线');