I want to disable PI controller action for some time when certain if-else conditions are satisfied. I tried using the reset option but it's not suppose to achieve my objective I guess; it just resets the integrator action.
Regards,
You can switch the controllers by using the clock block. I attached an example. Inside action blocks, there are PI controllers with different P and I parameter values.
Selim Sivrioglu thank you so much for helping me and taking time to send me the attached block; really appreciate it.
Multiply the output of the if-else block with the condition, something like the attached example.
What exactly do you mean by disabling that? There are couple of approaches,
1. If you want to keep the output of the PI fixed what you need to do is to multiply your input signal with the output signal of your if .... if( t1
Thank you Sepehr Saadatmand for your valuable comments.
I want to disable the PI controller when a certain if-else condition is met (voltage is above or below some level) and also, I don’t want controller’s output to go to zero at the moment it got disabled, instead i want to hold it to the value at which it was disabled. For example, if I disable PI and its output Is Q=40 kvar ( for reactive power compensation) then I don’t want this Q to go to zero when PI is disabled. I want Q to be fixed to 40 kVar at the moment PI is disabled. I think your first point is related to my concern but I didn’t understand it completely.
Looking forward to your response.
thank you.
Waqas Ur Rehman,
The PI controller output ( for your case for example Q=40) is the combination of two different part of your controller ( the part which is proportional to your error and the part which is regarding the integrated error). The integration parts make sure that your error is zero. If your error that you are applying to your PI is Zero at the exact moment before you decide to bypass the PI, your PI output only represent the integral part. Therefore, if you multiply your error with Zero at the time you want to bypass your PI, or in another word just set the error equal to zero for the bypass period, then you will be fine and the output signal will be fixed at the last amount which was in your case Q=40. To write it down in a code way see below:
if( operation point == 'Normal Operation'){
Err=Reference_signal-Signal;
}else{
Err=0;
}
Q=PI_controller(Err);
Sepehr Saadatmand okay got it, thank you for helping me out! I'll keep in touch with you if I face any other issue.
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