Impact of the Inverter DC Bus Voltage on the Iron Losses of a Permanent Magnet Synchronous Motor at Constant Speed

Abstract

In this paper, the impact of the DC bus voltage on the iron losses of a permanent magnet synchronous motor (PMSM) fed by a pulse-width modulation inverter is evaluated. Under constant speed operation, the modulation index decreases when the DC bus voltage increases. This modifies the harmonic content of the PMSM input voltage and then affects the motor iron losses. The experimental measurements results show that, for the conditions considered in this paper, the total iron losses are 1.8 times larger at the lowest modulation index than at the highest one.