Loss Analysis of High Power Chopper by Under-Zero Current Switching

抄録

This paper describes the evaluation of the IGBT partial turn-off behavior through three types of circuit topologies: hard switching (SW), Zero Voltage Switching (ZVS), and Tail Loss Cancel (TLC) method. Under-zero current switching (UCS) was examined through the high power back to back (BTB) experiment using a 90kW 3-phase interleaved chopper. The proposed Snubber Assisted Zero voltage and Zero current transition (SAZZ) topology obtained the highest efficiency of 97.42% at 30kW, 1.82% higher than hard SW (95.6%), and the highest efficiency over the entire power region. This was verified through the load test and loss breakdown up to 30kW per phase, and its performance for the under-zero current switching behavior was confirmed.