Comparison of Iron Loss Models for Electrical Machines With Different Frequency Domain and Time Domain Methods for Excess Loss Prediction

The goal of this paper is to investigate the accuracy of modeling the excess loss in electrical steels using a time domain model with Bertotti’s loss model parameters $n_{0}$ and $V_{0}$ fitted in the frequency domain. Three variants of iron loss models based on Bertotti’s theory are compared for the prediction of iron losses under sinusoidal and non-sinusoidal flux conditions. The non-sinusoidal waveforms are based on the realistic time variation of the magnetic induction in the stator core of an electrical machine, obtained from a finite element-based machine model.

I. Introduction

Ageneral approach for the calculation of iron loss in soft magnetic laminated materials under a unidirectional flux is based on the separation of the losses into three components: 1) the hysteresis loss ; 2) the classical loss ; and 3) the excess loss [1]. The statistical loss theory under arbitrary flux waveforms and no minor loops is described in [2], whereas [3] takes into account the minor order loops. Here, we may distinguish between frequency and time domain loss models.