Analysis of a Tooth-Coil Winding Permanent-Magnet Synchronous Machine With an Unequal Teeth Width

Alvaro E Hoffer,Ilya Petrov,Juan A Tapia,Juha J Pyrhonen,Gerd Bramerdorfer

doi:10.1109/access.2020.2987872

Abstract

This paper presents an analysis of a permanent magnet synchronous machine (PMSM) with an unequal teeth width. The use of the concentrated nonoverlapping winding, also known as tooth-coil winding, has certain advantages. In addition, asymmetric features can be exploited by adopting this winding configuration to improve the machine performance. The procedure involves increasing the stator tooth width and, to the same extent, reducing the adjacent stator tooth width. In this paper, an analytical method was employed to predict and understand the back-EMF behavior, and a finite element analysis (FEA) was performed to verify the analytical method. Furthermore, a detailed study of the machine performance (electromagnetic torque, flux density, and losses) was carried out by the FEA. The machine was built and tested to validate the performance of the machine.

Highlights

Permanent magnet synchronous machines provide certain advantages over other traditional machines because of theirThe associate editor coordinating the review of this manuscript and approving it for publication was Su Yan .high torque/volume ratio, high power factor, and high efficiency [1], [2]
Distributed windings are characterized by producing a close to sinusoidal current linkage waveform yet avoiding significant current linkage low-order harmonic components because of the consequent distribution of the coils along the stator periphery (q ≥ 1)
This article proposes a comprehensive study about the influence of the unequal teeth width on the air gap flux density, the flux linkage, the back-EMF, the electromagnetic torque, and the losses of the tooth-coil windings (TCW) permanent magnet synchronous machine (PMSM)

Summary

INTRODUCTION

This article proposes a comprehensive study about the influence of the unequal teeth width on the air gap flux density, the flux linkage, the back-EMF, the electromagnetic torque, and the losses of the TCW PMSM. The results show that the proposed method allows obtaining the permeance distribution in the air gap of TCW PMSMs with an unequal teeth width. The proposed method to obtain the permeance distribution of a TCW PMSM with an unequal teeth width can be used to calculate the back-EMF, the cogging torque, the electromagnetic torque, and related variables using the appropriate analytical models available in the literature [9], [19]–[21]. It can be seen that the angle between the phasors of the different phases remains invariant in both cases, which explains the symmetric back-EMF induced waveforms

TORQUE ANALYSIS

Findings

CONCLUSION