chapter7_12.m

《MATLAB在控制系统中的应用》实例程序

ng0=[20];dg0=conv([1,0],conv([0.9,1],[0.007,1])); 
g0=tf(ng0,dg0); 
KK=50;ap=0.3;ts=2.5;delta=0.05; 
w=logspace(-3,3);t=[0:0.01:3]; 
[mag,phase]=bode(KK*g0,w); 
[gm0,pm0,wg0,wc0]=margin(mag,phase,w),gm0=20*log10(gm0) 
mr=0.6+2.5*ap,dpm1=asin(1/mr);Pm=dpm1*180/pi; 
wc=ceil((2+1.5*(mr-1)+2.5*(mr-1)^2)*pi/ts), 
h=(mr+1)/(mr-1),w1=2*wc/(h+1), 
w1=wc/10;w2=h*w1,w2=9; 
ng1=[1/w1,1];dg1=conv([1/w2,1],conv([1,0],[1,0])); 
g1=tf(ng1,dg1);ngv=polyval(ng1,j*wc);dgv=polyval(dg1,j*wc); 
g=ngv/dgv;K=abs(1/g);g1=tf(K*g1) 
h=tf(dg1,ng1);Kh=1/K;h=tf(Kh*h) 
bode(KK*g0,w),grid on,hold on,bode(g1,w), bode(h,w), 
b1=feedback(g0,1);b2=feedback(g1,1); 
figure;step(b1,t);grid on,hold on; step(b2,t); 
[pos,tr,ts,tp]=stepchar(b2,delta)