Four quadrant SAZZ-1 chopper for EV and HEV power train

This paper discusses four quadrant SAZZ-1 chopper (Snubber Assisted Zero Voltage and Zero Current Switching) and its direct application to a EV (Electric Vehicle) power train. The performance of SAZZ-1 chopper is demonstrated on several prototypes. The first prototype is a 25 kW, 50 kHz SAZZ-1 with efficiency in the range between 96% and 97%. This was further improved by a redesigned SAZZ-1 chopper which reached even higher efficiency in the range of 97% to over 98%. Further on, a new mid-power 30 kW water cooled SAZZ-1 chopper was constructed for KAST (Kanagawa Academy of Science and Technology) advanced EV project. This prototype was used and fully tested in an EV prototype named KAST-EV Kana. As discussed, SAZZ-1 topology proved to be well performing in direct EV application.