Electromagnetic noises and efficiency evaluations of three-phase ZVS-PWM inverter with new resonant AC link snubbers

This paper presents a novel prototype of three-phase voltage source type zero voltage soft-switching (ZVS) inverter using the main and auxiliary IGBT power module packages in order to reduce their switching power losses as well as electro-magnetic conductive and radiative noises. A single inductor-based resonant AC link snubber circuit specified as one of auxiliary resonant commutation snubbers to achieve the ZVS for the three-phase voltage source type inverter operating under a principle of specific instantaneous space voltage vector sinewave modulation is originally demonstrated as compared with the other types of resonant AC link snubber circuit topologies. In addition to this, its operation principle and unique features are described in this paper. The practical basic operating performances of the new conceptual instantaneous space voltage vector modulated three-phase voltage source soft-switching inverter are evaluated and discussed on the basis of waveforms quality evaluations on the output line to line voltage, power loss analysis, power conversion efficiency and electromagnetic conductive and radiative noise from an experimental point of view, comparing with three-phase voltage source hard-switching inverter.