Improvement of Energy Density in Single Stator Interior Permanent Magnet Using Double Stator Topology

R N Firdaus ,Masami Nirei,Hiroyuki Wakiwaka,Norhisam Misron,Chockalingam Aravind Vaithilingam

doi:10.1155/2014/787382

Abstract

The paper presents the energy density improvement using magnetic circuit analysis of the interior permanent magnet motor. The leakage flux from the conventional structure is improved with modified magnetic circuit to improve the energy and thereby the torque value. This is approached with a double stator structure design. The proposed structure is investigated with two design variations, namely, the double stator with thin pole shoe and the double stator with thick pole shoe motors. Variations in the mechanical parameters of the all the developed models are analyzed through the finite element analysis tool. In all investigations the magnetic source is fixed in both the permanent magnet volume and coil magnetomotive force, respectively, as 400 mm3per each pole and 480 Ampere turns per pole. From the analysis the best fit magnetic structure based on the torque characteristics is derived and is fabricated for the same volume as that of the conventional structure for performance evaluations. It is found out that there is improvement on the motor constant square density for the proposed improved magnetic circuit through the best fit double stator with thick pole shoe by about 83.66% greater than that of the conventional structure.

Highlights

Single phase interior permanent magnet (IPM) motors are adopted in many low cost applications such as in fan, blowers, and other domestic appliances [1,2,3,4,5]
The analysis motivated in the evaluation of the proper evaluation strategy is used in selecting the best fit of permanent magnet motor
Interior permanent magnet single phase motor based on improvement of magnetic circuit is comprehensively investigated

Summary

Introduction

Single phase interior permanent magnet (IPM) motors are adopted in many low cost applications such as in fan, blowers, and other domestic appliances [1,2,3,4,5]. For specific application such as the mechanical chopper, the single phase motor is the most popular application due to the safety consideration. The requirement for such type of motor is of high torque with low cogging torque values. The flux density in some parts of stator or rotor of permanent magnet motor is increased leading to saturation value as the volume of magnet is increased. At this saturation point, the magnetic energy no longer contributes

Methods

Results

Conclusion