闭环传递函数.doc

一．取TD=0,T1=∞,KP=1～5,则PID控制器的传递函数为： Gc（S）=1～5(TD=0,T1=∞,KP=1～5) 求系统的闭环传递函数的MATLAB程序如下： 【1】Gc（S）=1 n1=[1];d1=[0.017 1];s1=tf(n1,d1); n2=[1];d2=[0.076 0];s2=tf(n2,d2); sys1=feedback(s1*s2,1) Transfer function: 1 -------------------------- 0.001292 s^2 + 0.076 s + 1 n3=[0 44];d3=[0.00167 1];s3=tf(n3,d3); n4=[1];d4=0.0612;s4=tf(n4,d4); sys=feedback(sys1*s3,s4) Transfer function: 2.693 --------------------------------------------------- 1.32e-007 s^3 + 8.684e-005 s^2 + 0.004753 s + 44.06 =2.693/0.0012s^3+0.0585s^2+0.004753s+44.06 num1=[0 0 2.693]; den1=[0.0012 0.0585 0.004753 44.06]; step(num1,den1,0.60) 【2】Gc（S）=2 n1=[1];d1=[0.017 1];s1=tf(n1,d1); n2=[1];d2=[0.076 0];s2=tf(n2,d2); sys1=feedback(s1*s2,1) Transfer function: 1 -------------------------- 0.001292 s^2 + 0.076 s + 1 n3=[0 88];d3=[0.00167 1];s3=tf(n3,d3); n4=[1];d4=0.0612;s4=tf(n4,d4); sys=feedback(sys1*s3,s4) Transfer function: 5.386 --------------------------------------------------- 1.32e-007 s^3 + 8.684e-005 s^2 + 0.004753 s + 88.06 =5.386/0.0012s^3+0.0585s^2+0.004753s+88.06 num2=[0 0 5.386]; den2=[0.0012 0.0585 0.004753 88.06]; step(num2,den2,0.60) 【3】Gc（S）=3 n1=[1];d1=[0.017 1];s1=tf(n1,d1); n2=[1];d2=[0.076 0];s2=tf(n2,d2); sys1=feedback(s1*s2,1) Transfer function: 1 -------------------------- 0.001292 s^2 + 0.076 s + 1 n3=[0 132];d3=[0.00167 1];s3=tf(n3,d3); n4=[1];d4=0.0612;s4=tf(n4,d4); sys=feedback(sys1*s3,s4) Transfer function: 8.078 --------------------------------------------------- 1.32e-007 s^3 + 8.684e-005 s^2 + 0.004753 s + 132.1 =8.078/0.0012s^3+0.0585s^2+0.004753s+132.1 num3=[0 0 8.078]; den3=[0.0012 0.0585 0.004753 132.1]; step(num3,den3,0.60) 【4】Gc（S）=4 n1=[1];d1=[0.017 1];s1=tf(n1,d1); n2=[1];d2=[0.076 0];s2=tf(n2,d2); sys1=feedback(s1*s2,1) Transfer function: 1 -------------------------- 0.001292 s^2 + 0.076 s + 1 n3=[0 176];d3=