The First 4H-SiC BJT-Based 20 kHz, 7HP PWM DC-to-AC Inverter for Induction Motor Control Applications

This paper reports the design, fabrication and testing of the first 4H-SiC BJT-based, PWM DC-to-AC inverter at a record high power (7.4HP) and PWM frequency of 20 kHz with a bus voltage of 330V. Six 4H-SiC BJT switches and six 4H-SiC MPS diodes are used to form an all-SiC power board which is driven by a Si base driver, interfaced with a Si-based voltage source driver. The inverter has been used to control a GE three-phase AC induction motor of 7.5HP and has run up to an input power of 7.4HP (5.5kW). The SiC BJT I-V characteristics, the inverter switching waveforms and the inverter efficiency at different input power levels are presented.