Design space boundaries of linear compensators applying the k-factor method

The design of linear compensators is usually based on the frequency response of the system, considering phase margin PM and cross-over frequency fc as the initial specifications. Applying the k-factor method for synthesis of linear compensators, not all combinations of fc and PM yield feasible or stable designs, and in many cases the design procedure is based on a trial and error procedure. The objective of this paper is to define the fc-PM design space of linear compensators designed applying the k-factor method. This design space can be used to determine in a straightforward way the most appropriate compensator for a given topology, sensor and modulator.