How do I tune all the 4 PI controllers of a STATCOM?

the STATCOM has 4 PI controllers:

i) one PI for ac voltage regulation

ii) one PI for dc voltage regulation

iii) two PI for d and q axis current controllers.

If the MATLAB PID-tune tool is used for tuning of PI controllers, all the PI controllers cannot be tuned simulataneously. Even if 1 PI controller is tuned to give desired response, while tuning of other PI controller, the response of the first PI controller is affected.  

Tuning using trial and error method also doesnt work.

What are he other ways of tuning these PI controllers? How do I tune all the PI controllers of a STATCOM?

Answer 1

[Arkadiy Turevskiy]

You can try using Control System Tuner which can tune multiple PID controllers simultaneously. See this example . This tool needs a linear model to work with, so it tries to linearize a Simulink model. If the model cannot be linearized, you can use Simulink Design Optimization , which uses brute force optimization to tune the gains. See this example .