The effective improvement of the PMSM system with the carrier frequency modulation

The efficiency of the motor driving system in the electric vehicle affects the utilization factor of the power source and the driving range of the EV. The loss of the PMSM drive system is tested with the low speed. The modulation of carrier frequency in PMSM was discussed in this paper. According to the working situation of the EV, the carrier frequency would change to improve the effective of the driving system. The result of the simulation and the experiment show that the effective of the PMSM can be improve about 3.5%.