What is the difference between a controller and a compensator?

A controller is a closed-loop to have the difference between the output signal and the reference signal minimum. A compensator is also a closed-loop but it changes the shape of the controller's response to meet some requirements (e.g. transient response, rapid load changes, etc.).

1. What are the difference between lead compensator and PD controller?
2. What are the difference between lag compensator and PI controller?
3. Is PID controller a compensator?
4. Is a lead compensator a controller?

What are the difference between lead compensator and PD controller?

A lead compensator is designed to add phase to a system within a given range of frequencies (as compared to a PD controller, which also adds phase, but the phase is added at every frequency above the breakpoint frequency of the controller zero) [2].

What are the difference between lag compensator and PI controller?

In the lead-lag compensator, the lead part is used to improve PM (hence the transient response), while the lag (or PI) part is used to improve steady state performance (i.e., by increasing the dc-gain). owing to its simplicity and availability of simple methods to tune the control parameters.

Is PID controller a compensator?

The compensator is used to compensate desired phase margin value of system and then make use of the PID controller is to control the system with robust, reduced order response, and thus, suppressing the overshoot in time response.

Is a lead compensator a controller?

A compensator is an additional component or circuit that is inserted into a control system to compensate for a deficient performance of the overall system. The lead compensator plays the same role as the PD controller, reshaping the root locus to improve the transient response.