Simulation of current-mode quasi-resonant converters in full wave resonant switch configuration

A computer-oriented approach for transient and steady-state analysis of power electronics circuits is presented. The switching elements are extracted in a time-variable two-port, which is defined by its nodal equations. A set of modified nodal equations for describing the overall transient of the circuit is obtained. No small-signal approximations are required. The analytical expressions of the network waveforms are found accurately for each switching stage. The transient computation is based on a cyclical use of these expressions together with the threshold conditions. The general method is then applied to simulation of current-mode quasi-resonant converters. Transients due to large-signal changes in the line voltage and load are studied. The influence of the load value on transient peaks is pointed out. The voltage conversion ratio versus switching frequency is studied for both the half-wave and full-wave mode operation. A computer program for time-domain simulation of power electronics converters is developed based on this approach