High Power-Density High-Efficiency Electric Drive Design with Halbach-Rotor PMSM and WBG-Based High-Frequency Inverter

This paper presents the design of an electric drive for light-vehicle applications, using wide-band-gap semiconductor technologies and advanced machine concepts to maximize the power density of the whole system. The high-frequency output characteristic of inverter using the wide-bandgap semiconductor technologies can effectively reduce the current harmonics of the motor. That gives the motor design more freedom to use the new structure to improve its power density from a perspective of the thermal and electromagnetic performances. Meanwhile, a series of studies on the new rotor structure with Halbach permanent magnets are carried out to suppress the torque ripples at full-range speed during the motor design. Furthermore, since the EV motor needs to operate under variable operating conditions, systematic matching is considered to improve the overall performance following the usual working region of the light electric vehicles.