Three-Phase Partial Power Control Converter Based on SHEPWM

This paper proposes a three-phase hybrid silicon carbide (SiC)-silicon (Si) DC-AC topology based on partial power regulation. The Si-IGBT main unit (MU) operating at low frequency is connected in series with the SiC-MOSFET slave unit (SU) operating at high frequency by line-frequency transformer (LFT). The MU uses specific harmonic elimination pulse-width modulation (SHEPWM) to deal with the main power; the SU uses multiple quasi-proportional resonance (MQPR) to eliminate low harmonics and process partial power. Since the symmetric three-phase system can eliminate zero sequence harmonics, the ratio of transformation increases accordingly. It can further reduce the current of SU to improve performance in high-power applications. Then the LCL filter is formed by combining the LC filter with the transformer leakage inductance, which improves the filtering effect of high order harmonics. Finally, a simulation model is built in MATLAB/SIMULINK to verify the validity of the proposed topology.