Soft-switched three-level capacitor clamping inverter with clamping voltage stabilization

This paper proposes a zero-voltage-switching scheme for the three-level cap acitor clamping inverter. The proposed small-rating auxiliary circuit ensur es not only zero-voltage switching of the main switches and zero-current sw itching of the auxiliary switches, but the clamping capacitor voltage of th e inverter is also stabilized. The scheme prevents any voltage or current s pikes from happening over the main or auxiliary switches and no modulation constraints are incurred. Operation, analysis, designing, and testing aspec ts of the scheme are detailed.