实验五 线性系统串联校正.doc

,试设计一超前校正装置,使校正后系统的静态速度误差系数,相位裕量,增益裕量。
,试设计一个合适的滞后校正网络,,相角裕量约为。
,试设计一滞后-超前校正装置,使校正后系统的静态速度误差系数,相位裕量,增益裕量。
num0=20;
den0=[2 1 0];
w=:1000;
[gm1,pm1,wcg1,wcp1]=margin(num0,den0);
[mag1,phase1]=bode(num0,den0,w);
[gm1,pm1,wcg1,wcp1];
margin(num0,den0);
grid
>> e=5;
>> r=50;
>> r0=pm1;
>> phic=(r-r0+e)*pi/180;
>> alpha=(1+sin(phic))/(1-sin(phic));
>> [il,ii]=min(abs(mag1-1/sqrt(alpha)));
>> wc=w( ii); T=1/(wc*sqrt(alpha)); numc=[alpha*T,1]; denc=[T,1];
>> [num,den]=series(num0,den0,numc,denc);
>> [gm,pm,wcg,wcp]=margin(num,den);
>> printsys(numc,denc)

num/den =

s + 1
--------------
s + 1
>> disp('校正之后的系统开环传递函数为:');
校正之后的系统开环传递函数为:
>> printsys(num,den)

num/den =

s + 20
----------------------------
s^3 + s^2 + s
>> [mag2,phase2]=bode(numc,denc,w);
>> [mag,phase]=bode(num,den,w);
>> subplot(2,1,1);semilogx(w,20*log10(mag),w,20*log10(mag1),'--',w,20*log10(mag2),'-.');
>> grid;
>> ylabel('幅值(db)'); title('--Go,-Gc,GoGc');
>> subplot(2,1,2); semilogx(w,phase,w,phase1,'--',w,phase2,'-',w,(w-180-w),':');
>> grid; ylabel('相位(0)'); xlabel('频率(rad/sec)');
>> title(['校正前:幅值裕量=',num2str(20*log10(gm1)),'db','相位裕量=',num2str(pm1),'0';
>> num0=25;
>> den0=conv([1,1],conv([1,1],[1,1]));
>> w=logspace(-1,);
>> [gm1,pm1