Pure gain compensators are generally known as proportional or P controllers. Such controllers can be used to satisfy phase margin requirements of a compensator-plant system. However, the frequency at which the phase margin requirement is satisfied, cannot be controlled by gain compensation alone.
To design a gain compensator
1. Generate the Bode magnitude and phase plots of the open-loop transfer function GH(s).
2. Determine the frequency ωpm at which the desired phase margin occurs.
3. Determine the magnitude of GH(s) corresponding to ωpm. Let this magnitude be
4. Use a gain of:
5. Generate the Bode magnitude and phase plots and check the phase margin. To fine-tune the gain, make small changes about:
