Spectral inductance of the linear motor‐space harmonic analysis

Abstract

Purpose

The aim of the paper is to present the methodology of obtaining an approximate equivalent circuit composed of lumped parameters which describes an electromagnetic state of induction machines (IMs) with solid secondary. Higher space harmonic field components are taken into account. The proposed method of machine model constructing is useful for solving electrodynamics states of solid secondary IMs, as well linear machines.

Design/methodology/approach

A determination of equivalent circuit parameters of a polyharmonic machine is divided into two steps. In the first step, frequency plots of the spectral inductances are derived – for each of the space harmonic components – from an electromagnetic field distribution calculated by means of the finite element method. In the second step, each of the spectral inductances are represented by the operational inductances which corresponds to the equivalent circuit composed of parallel connected the magnetizing inductance and branches consisting of resistance and inductance connected in series.

Findings

The proposed method allows the construction of the approximate equivalent circuit with lumped parameters which enables to solve electrodynamic states of solid secondary IMs, as well linear machines. The machine model has been derived with consideration of the higher space harmonic field components.

Research limitations/implications

Saturation effects of a magnetic circuit and an unbalance of phase currents have not been taken into account.

Originality/value

The paper shows the method of constructing a machine field‐circuit model. Lumped parameters of the model have been derived using frequency characteristics of the stator spectral inductance with consideration of the higher space harmonic field components.

Citation

Utrata, G. and Kaplon, A. (2011), "Spectral inductance of the linear motor‐space harmonic analysis", COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Vol. 30 No. 3, pp. 1118-1131. https://doi.org/10.1108/03321641111111040