Research on a Novel Modulation Strategy for Auxiliary Resonant Commutated Pole Inverter With the Smallest Loss in Auxiliary Commutation Circuits

Aiming at overcoming the problem that the auxiliary commutation circuit (ACC) of auxiliary resonant commutated pole (ARCP) inverters has a high loss in commutation processes, this paper presents a novel modulation strategy based on an improved ARCP inverter. In comparison with the original modulation strategy, this modulation strategy can not only realize soft-switching for all switches, but also avoid the superposition of resonance current and load current at commutation moments in ACCs and make the maximum current through ACCs approximately equal to load current in commutation processes. So the circulating current loss in ACCs and the current peak stress of auxiliary switches can be effectively reduced. According to the equivalent circuit in different operation modes under this modulation strategy, this paper analyses the operation principle, soft-switching implementation condition, and optimal parameter design procedure of the improved ARCP inverter. Finally, the novel modulation strategy is applied to a 10 kW 16 kHz improved ARCP inverter prototype with insulated gate bipolar transistor-based switches. Experimental results are given to demonstrate the validity and features of the inverter under the novel modulation strategy.