Comparative analysis of charging modes of series resonant converter for a energy storage capacitor

In this paper, charging mode of series resonant converter for a high voltage energy storage capacitor are compared in terms of charging time, losses of switch, peak resonant current, voltage and switch utilization in each operation mode. Operating principles of the full bridge series resonant converter with capacitor load are explained and charging characteristics are analyzed in discontinuous and continuous operation mode. Based on the analysis and the simulation focused on above five performance indexes, 0.65ω_r <; ω_s <; 0.75ω_r is evaluated to the best range of switching frequency for charging of an energy storage capacitor. 1.8 kJ/s SRC prototype is assembled with TI 28335 DSP controller and 40 kJ, 7 kV capacitor. Design rules based on the comparative analysis are verified by experiment.