Simulation of Power Electronic Converters Using Quasi Steady State Approximation

Abstract

A new method to compute voltage and current waveforms of power electronic converters is proposed in the paper. The method relies on simulation result of averaged circuit model, and superimposes the ripple of the inductor currents to the obtained average values, assuming that the linear ripple approximation applies. To determine the amplitude of the switching ripple, a quasi steady state approximation is proposed. After the inductor currents are obtained, currents of switching components are computed by multiplying them with appropriate switching functions. The algorithm provides an efficient tool to generate the converter waveforms in order to compute their spectra, mean and RMS values, which are of interest in designing filters and estimating converter losses.