A new zero-voltage-zero-current-transition chopper SAZZ for a FCEV drive

A new snubber assisted zero voltage and zero current transition chopper (SAZZ) is proposed for the fuel cell electric vehicle (FCEV) or the hybrid vehicle. The SAZZ topology provides a simple soft switching technique resulting in the compact and low-loss power converter for the FCEV. Furthermore, the SAZZ operates without voltage spike across the output diode during the reverse recovery. A SAZZ mini-model using IGBT was fabricated and evaluated by a fundamental operational test. The experimental results show the verification of the circuit geometry and the basic operation. In addition, the preliminary SAZZ configuration for the high frequency using the stray capacitance is investigated to minimize the current of the auxiliary resonant stage. Some experimental results are also presented.