Research of Three-Level ANPC Converter Based on Si/SiC Hybrid Switches

Abstract:
Compared to two-level converters, Three-level converters feature higher efficiency and smoother output waveform. To further reduce cost and increase the power conversion efficiency, this paper presents a three-level Active Neutral Point Clamped converter using Si/SiC hybrid switches. It consists of four Si/SiC hybrid switches and two Si IGBT. A control method based on the optimal turn-off delay time is proposed for hybrid Si/SiC switches inside. Both the performance of the proposed ANPC converter and its control strategy is investigated and validated by experiment. Results indicate that the proposed ANPC converter exhibits a higher efficiency compared with other similar ANPC converters. The proposed ANPC converter exhibits a higher efficiency compared to all Silicon IGBT based ANPC converter, all SiC MOSFET based ANPC converter, and the four Si/SiC hybrid switches converter based on fixed turn-off delay time control method. In addition, the switches cost of the proposed converter is greatly cut down when compared to all SiC MOSFET based ANPC converter.