Current control of nine-switch inverter using integrated current sensors

Abstract

Recently nine-switch inverter (NSI) has been presented as a dual-output inverter with only nine semiconductor switches. This inverter can be used to control two ac loads such as electric motors, independently. While external current sensors are usually in closed loop control of inverter, this paper proposes using power semiconductor switches that include integrated pilot current sensors as mid switches of nine-switch inverter. In this manner, using only three integrated current sensors, both outputs of nine-switch inverter can be controlled. Since integrated current sensors can not cover current in each phase during the whole fundamental cycle, a reconstruction algorithm is proposed for calculation of non-measurable currents. Performance of the proposed method is verified by simulation results.