cohenpid.m

用MATLAB的脚本语言M语言编写的

function [Gc,Kp,Ti,Td,H]=cohenpid(key,vars)
K=vars(1); L=vars(2); T=vars(3); N=vars(4); 
a=K*L/T; tau=L/(L+T); Ti=[]; Td=[];
switch key
case 1,Kp=(1+0.35*tau/(1-tau))/a; 
case 2,
   Kp=0.9*(1+0.92*tau/(1-tau))/a; 
   Ti=(3.3-3*tau)*L/(1+1.2*tau);
case {3,4}
   Kp=1.35*(1+0.18*tau/(1-tau))/a; 
   Ti=(2.5-2*tau)*L/(1-0.39*tau); 
   Td=0.37*(1-tau)*L/(1-0.81*tau); 
case 5
   Kp=1.24*(1+0.13*tau/(1-tau))/a; 
   Td=(0.27-0.36*tau)*L/(1-0.87*tau);
end   
[Gc,H]=writepid(Kp,Ti,Td,N,key);