Analysis of the operation principle for tubular flux-switching permanent magnet linear machine

Abstract

Purpose

This study aims to unveil the generation mechanism of the thrust force in a tubular flux-switching permanent magnet (PM) linear (TFSPML) machine; the operation principle of the TFSPML machine is analyzed.

Design/methodology/approach

First, the air-gap flux density harmonic characteristics excited by PMs and armature windings are investigated and summarized based on a simple magnetomotive force (MMF)-permeance model. Then, the air-gap field modulation theory is applied in analyzing the air-gap flux density harmonics that contribute to the electromagnetic force. In addition, a simple method for separating the end force of the TFSPML machine is proposed, which is a significant foundation for the comprehensive analysis of this type of machine. As a result, the operation principle of the TFSPML machine is thoroughly revealed.

Findings

The analysis shows that the average electromagnetic force is mainly contributed by the air-gap dominant harmonics, and the thrust force ripple is mainly caused by the end force.

Originality/value

In this paper, the operation principle of the TFSPML machine is analyzed from the perspective of air-gap field modulation.

Citation

Zhang, G., Nie, R., Si, J., Feng, X. and Wang, C. (2023), "Analysis of the operation principle for tubular flux-switching permanent magnet linear machine", COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Vol. 42 No. 2, pp. 285-301. https://doi.org/10.1108/COMPEL-01-2022-0024