Simulations and mathematical models for a pulse-width-modulated controller

A class of controllers for use in either analogue or pulsed systems has recently been introduced in the process-control market. This paper presents some simulations and mathematical models with application in the analysis and design of systems containing such controllers. Means of transient analysis are presented which can be used in their own right or as checks on the simulation results. Simple models for use in sinusoidal analysis are shown to give close approximations to the measured points and match up well with simulated values. A quasilinear model is presented and is shown to be of value in stability analysis and for the prediction of limit cycles.