Can I Tune a Controller with a Large Number of Symbolic Gains using Sisotool?

I'm looking to tune a PR controller with 10 independent gain terms using Sisotool, i.e. Kp,Kr1,Kr2...etc.

I need to do this symbolically since the transfer function will multiply these gains by other values and to extract the actual optimised values for Kp,Kr would be very difficult.

So I'd like to be able to feed Sisotool the transfer function with the symbolic terms for the gains and tune those, then write these gains back to the workspace after finishing?

Is this possible?

I've been looking at the realp function for setting a variable name that can be called in a transfer function but I don't know if this will work. Any suggestions?

Answer 1

[Ryan G]

SISOTOOL is a Control System Toolbox function which does not work with symbolic variables. Control design (at least in terms of bode, root locus or nyquist) does not really make sense with symbolic variables as they could represent a range of values, -inf to +inf, which would significantly change how the resultant control design plots (such as bode, root locus or nyquist) would appear.

You could try using Simulink and the Compensator design tool which lets you manually tune each gain in your system. You could also use Simulink Design Optimization to find an optimized result.