Characteristics of Single Ended Resonant Converter with Voltage Doubler Synchronous Rectirier

Abstract

this paper presents research about characteristics of a single ended resonant converter (SERC). This converter consists of two main parts – a synchronous voltage doubler rectifier (SVDR) and a single ended resonant inverter (SERI). In this circuit variant, the SERI is actually a supplying source for the synchronous rectifier. Because a SERI could work as a current source the examination is made in two variants. In the first variant, the supplying source for synchronous rectifier is an ideal current source. For this purpose the power MOSFET and the other resonant components from SERI are removed. They are replaced by an ideal sinusoidal current source. The high frequency transformer is kept. In that way the output of the converter (the output of the SVDR) is kept galvanically isolated from its input (the current source). In the second variant, the supplying source for the synchronous rectifier is SERI itself. Parametrical analysis with LTSpice simulation software is made for two cases. The first case is when the load resistance is changing but the filtering capacitors have constant capacitance. The second case is when the load resistance doesn’t change but the capacitance of the two filtering capacitors is changing. To confirm the results an experimental model has developed.