SEVEN-LEVEL SIC-MOSFET MODULAR HIGH-VOLTAGE PULSEGENERATION FOR ADVANCED ELECTRIC VEHICLE MOTORINSULATION TESTING

Abstract

As the global electric vehicle (EV) market expands, insulation-related failures have emerged as a
primary threat to motor reliability, particularly under the high-frequency switching and elevated voltage
stresses of modern inverter-fed drives. Accurately assessing dielectric degradation and partial discharge
activity under realistic conditions is vital to ensure operational safety and reduce manufacturing costs. However, traditional high-voltage pulse generators suffer from high harmonic distortion, poor voltage
resolution, elevated switching losses, and an inability to replicate fast voltage transitions. To
address these limitations, this paper proposes a seven-level modular high-voltage pulse generator
utilizing Silicon Carbide (SiC) MOSFETs and a Sinusoidal Pulse Width Modulation (SPWM) control. To
address these limitations, this paper proposes a seven-level modular high-voltage pulse generator
utilizing Silicon Carbide (SiC) MOSFETs and a Sinusoidal Pulse Width Modulation (SPWM) control
strategy. The system features a seven-stage modular architecture that employs parallel capacitor
charging and controlled series discharging. By leveraging the fast-switching speeds and low losses of
SiC devices alongside SPWM, the generator delivers precise waveform control, reduced harmonic
content, and exceptional efficiency. The proposed framework provides enhanced insulation stress
emulation, offering a highly reliable testing paradigm for modern EV traction motor insulation.