Gamma-Ray Irradiation Response of the Motor-Driver Circuit with SiC MOSFETs

Gamma-ray irradiation effects of motor-driver circuit composed of SiC MOSFETs under motor driving with different PWM frequencies were investigated. The driving current and voltage waveforms were normal when the irradiation exceeded 1.1 MGy at PWM frequency of 10 kHz. In addition, the motor was still rotating in this total dose. We compared the irradiation responses of SiC MOSFETs between the cases of driving states and no bias. The drain current – gate voltage characteristics with no bias shifted to the negative voltage side wider than the driving states. Also the leakage current in the case of driving state is fewer than that of no bias.