Comparative analysis of three-level diode neural-point-clamped and active neural-point-clamped zero-current-transition inverters

This paper analyzes and compares three level diode neutral-point-clamped zero-current transition (DNPC-3L ZCT) inverter and three-level active neutral-point-clamped zero-current-transition (ANPC-3L ZCT) inverter. The two multilevel soft-switching topologies are compared with respect to switching energy, volume, as well as parasitic inductance influence. The comparison results reveal that the ANPC-3L ZCT inverter takes advantage over DNPC-3L ZCT inverter with lower volume, lower switching losses, and less sensitivity to parasitic inductance. 80 kVA half-bridge prototypes of the two soft-switching topologies are implemented and tested; the experimental results verify the analysis.