Comparison between state space averaging and PWM switch for switch mode power supply analysis

Abstract

The state space averaging method and the pulse-width-modulation (PWM) switch method for modeling of DC-to-DC converters are reviewed. The methods are compared through the computation and plotting of typical transfer functions of a buck converter. The state space averaging method begins by writing the state equation and the state matrices describing the system, and requires matrix operations for computation of the system transfer functions. It also leads to a canonical model that represents the four basic DC-to-DC topologies. The PWM switch method leads to a simpler circuit analysis of the converter which can be easily simulated using SPICE-like simulation programs.<>