Iron Loss Analysis of Permanent Magnet Motors Fed by PWM Inverter

Abstract

Carrier harmonic losses that consist of iron loss, eddy current loss, and ac copper loss are generated in a permanent magnet machine driven by a PWM inverter. It is already known that a higher motor inductance can lead to lower carrier harmonic losses. This paper investigated the carrier harmonic loss composition of two motors with identical dimensions but different inductances. The finite element analysis (FEA) results showed that the eddy current loss in the iron core accounts for most part of the carrier harmonic losses. It is also proved that the carrier harmonic loss of the iron core is quantifiable using theoretical calculations.