PID output...

Hello all,

I have a questions, how do I clip/bound/limit the output of a PID loop to a certain set of values (say 1000-2000) so all I have to worry about is the tuning?

Regards, Robert

Answer 1

[Paulo Silva]

Use the saturation block

[Robert]

This only works on the input though. My problem is I am putting an error value into the PID loop and I need the output to be between 1000-2000 not -80 to 80 (which is error and current output).. I would prefer not to have to tune the PID specifically to get those bounds. I heard this process is called clipping/bounding/limiting but can't seem to find enough information on it.

[Arnaud Miege]

Not necessarily, you can put the saturation block on the output of the PID controller. However, be aware of integrator windup (see my answer).

Answer 2

[Arnaud Miege]

You may also need to add some additional control to prevent integrator windup. The new PID block introduced in R2009b, includes those effects, as well as many more.

Arnaud

Answer 3

[rathod ujjval rameshbhai]

I am implementing PID controller on the system 1/s......

My question is when I write the command pidtool and get the new window in that there are list of paramenters..... I want to see the output of controller at perticular point i.e. Pout=Kp*e(t)+P0....

other thing is if my system is 1/s then as in step response it becomes 1/s^2 and then Laplace inverse will give output equation.... in case of only P it would be Kp*e(t)*L^-1(1/s).... is it??