Dear All
I am following MATLAB tutorial in Mathworks "Designing PID for Disturbance Rejection with PID Tuner" While following this tutorial, I got the following error in the picture. and another error is
"Function 'subsindex' is not defined for values of class 'zpk'."
The errors occurred after the following commands
G = zpk(-5,[-1 -2 -3 -4],6,'OutputDelay',1);G.InputName = 'u';G.OutputName = 'y';C = pid(0.64362,0.30314);C.InputName = 'e';C.OutputName = 'u';b = 0.7;% The following code constructs an ISA-PID from F and C
F = tf([b*C.Kp C.Ki],[C.Kp C.Ki]);F.InputName = 'r';F.OutputName = 'uf';Sum = sumblk('e','uf','y','+-');ISAPID = connect(C,F,Sum,{'r','y'},'u');tf(ISAPID)% Closed-loop system with PI controller for reference tracking
sys1 = feedback(G*C,1);% Closed-loop system with ISA-PID controller
sys2 = connect(ISAPID,G,{'r','u'},'y');% Compare responses
step(sys1,'r-',sys2(1),'b.');legend('show','location','southeast')title('Reference Tracking')
The link of the tutorial is : https://www.mathworks.com/help/control/examples/designing-pid-for-disturbance-rejection-with-pid-tuner.html
Can anyone guide me how to remove these errors ?
Thank you
Best Answer