Computer aided analysis of the design space of controllers for switching converters

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 provide some easy algorithms 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. The example of a VMC buck converter is analyzed, though the presented method can be applied to any topology.