A novel three-level zero-current-transition active neutral-point-clamped inverter

This paper extends the zero-current-transition concept to three-level active neutral-point-clamped inverter. The proposed soft-switching topology employs two auxiliary switches and one LC resonant tank to assist the main switching devices in one phase leg. The zero-current turning-off of all the main and auxiliary switching devices are achieved with voltage stress of all switching devices are clamped to half of the DC-link voltage. Meanwhile, The turning-on losses of main devices are reduced due to the limited current rising rate by the resonance as well as the reduced reverse recovery losses of main diodes. The operation principles are analyzed and simulation results verify the analysis.