Experimental study of mutual effects of high carrier frequency, dead-time and control sample time on IPMSM core loss under SiC inverter excitation

Abstract

This paper experimentally analyzes the core loss characteristics of an interior permanent magnet synchronous motor (IPMSM) excited by a SiC inverter with the sinusoidal pulse-width modulation (PWM) and high modulation index of 1.1 considering the mutual effects of the high carrier frequencies of up to 200 kHz, different dead-times of 250 and 1000 ns, control sample times of 100–1000 μs, and stator core temperature. The experimental IPMSM drive system is operated in load condition with a torque of 1.05 Nm and rotational velocity of 1500 rpm. Furthermore, the ringing phenomenon and rise time in the motor voltage are measured and analyzed using a high-resolution oscilloscope that has a superior sampling rate of up to 5 giga-samples per second (GS/s), which helps to thoroughly examine the impact of the SiC inverter excitation on the motor core loss. The relations of the total harmonic distortion (THD) of the measured motor voltage and current and the distortions in the magnetic flux density through the stator core to the IPMSM core loss properties are also evaluated. Lastly, explanations and insights based on physics of the obtained results are presented.