Absorption circuit of insulated gate bipolar transistor for high-frequency capacitor charging power supply

Enhancing frequency is an effective method to enhance the power density of a power supply. In order to protect switching devices in the high-frequency capacitor charging power supply (CCPS), the mechanism and influencing factors of reverse peak voltages were investigated based on the series resonant capacitor-charging power supply. Several methods to inhibit the peak voltages were introduced. Fundamental principles of absorption circuit were analyzed, and circuit parameters were selected and optimized by simulation. Then the feasibility of absorption circuit was verified by the test of a 40 kW/50 kHz capacitor-charging power supply.