Analysis and design of a modified series resonant converter

A modified series resonant convertor (SRC) which overcomes the problems of a standard SRC is presented. A state-space approach is used for the analysis. The analysis shows that the converter enters into three different modes. Converter gain and other component stresses are plotted with variation in the load current. Detailed experimental results obtained from a 500 W, MOSFET converter are presented to verify the theory. A narrow variation in switching frequency is required to regulate the output voltage for a wide variation in the load current. The converter can operate with a load open circuit as well as a load short circuit. It is shown that by placing the parallel inductor on the secondary-side, the parasitics of the high-frequency transformer can be used profitably