Comparative Evaluation of GaN and SiC ANPC Inverters for High-Frequency Applications

Abstract

This paper presents a comparative evaluation of Active Neutral Point Clamped (ANPC) three-phase inverters based on Gallium Nitride (GaN) and Silicon Carbide (SiC) devices rated for 650 V. Investigation of both technologies is conducted across varied switching frequencies and power levels using 800 V, 20 kW hardware prototypes. Experimental results utilizing a $600 \mu \mathrm{H}$ inductor demonstrate consistently high efficiency for both devices, with SiC providing a highly competitive baseline up to 100 kHz. Conversely, the GaN inverter successfully operates up to 200 kHz, demonstrating significant THD improvements at elevated frequencies. To explain these operational boundaries, the paper analyzes device characteristics, highlighting GaN's potential for extreme frequency scaling by avoiding the bipolar recovery penalties inherent in SiC MOSFETs. Finally, a performance comparison using alternative inductors validates the substantial reduction in passive component volume enabled by this high-frequency operation.