ANALYSIS AND REDUCTION OF COGGING TORQUE OF LINE-START PERMANENT MAGNET MOTORS

Drive motors, which are used in the drive modules of electric cars, are interior permanent magnet motors. These motors tend to have high cogging torque and torque ripple, which leads to the generation of high vibration and noise. Several studies have attempted to determine methods of reducing the cogging torque and torque ripple in interior permanent magnet motors. The primary methods of reducing the cogging torque involve either electric control or mechanical means. Herein, the authors focused on a mechanical method to reduce the cogging torque and torque ripple. Although various methods of reducing vibration and noise mechanically exist, there is no widely-known comparative analyses on reducing the vibration and noise by designing a notched rotor shape. Therefore, this paper proposes a method of reducing vibration and noise mechanically by designing a notched rotor shape. In the comparative analysis performed herein, the motor stator and rotor were set to be the same size, and electromagnetic field analysis was performed to determine a notch shape that is suitable for the rotor and that generates reasonable vibration and noise.

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Intensity of the native and additional harmonic components in cogging torque due to design parameters of permanent-magnet motors

2009 International Conference on Power Electronics and Drive Systems (PEDS) ◽

10.1109/peds.2009.5385930 ◽

2009 ◽

Cited By ~ 8

Author(s):

Lovrenc Gasparin ◽

Rastko Fiser

Keyword(s):

Permanent Magnet ◽

Design Parameters ◽

Permanent Magnet Motors ◽

Cogging Torque ◽

Harmonic Components

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Simulation Study Of The Reduction Of Cogging Torque In Permanent Magnet Motors

1997 IEEE International Magnetics Conference (INTERMAG'97) ◽

10.1109/intmag.1997.597444 ◽

2005 ◽

Cited By ~ 2

Author(s):

Y.D. Yao ◽

D.R. Huang ◽

J.C. Wang ◽

S.H. Liou ◽

S.J. Wang ◽

...

Keyword(s):

Permanent Magnet ◽

Simulation Study ◽

Permanent Magnet Motors ◽

Cogging Torque

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The Method Pole of Width Modulation Reducing Cogging Torque in Permanent Magnet Motor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.433-440.4201 ◽

2012 ◽

Vol 433-440 ◽

pp. 4201-4206

Author(s):

Yue Jun An ◽

Wen Qiang Zhao ◽

Li Ping Xue ◽

Hong Liang Wen ◽

Guo Ming Liu

Keyword(s):

Permanent Magnet ◽

Torque Ripple ◽

Experimental Result ◽

Testing System ◽

Permanent Magnet Motors ◽

Permanent Magnet Motor ◽

Surface Type ◽

Angle Sensor ◽

Cogging Torque ◽

Simulation Results

Cogging torque is one of the most important parameters of permanent magnet motors, which causes torque ripple, vibration and noise. This paper describes the mechanism of cogging torque, introduces several methods of reducing cogging torque and points out the advantage of novel magnet arrayed permanent magnet motor in reducing cogging torque. Ansoft software is used to build the simulation of conventional surface-type permanent magnet motor and novel magnet arrayed permanent magnet motor and to calculate their cogging torque. a cogging torque testing system which included the angle sensor, permanent magnet motor, torque wrenches and other components are tested two different structures motors’ cogging torque .The experimental result is consistent with the simulation results, it shows that the method of novel magnet arrayed permanent magnet motor reducing cogging torque is correct. The new method compare with the same specification on the surface of permanent magnet motor can reduce more cogging torque.

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