Calculation of negative torque caused by slot ripples of induction motors

Author

Yamazaki, Katsumi ; Haruishi, Yoshihisa ; Ara, Takahiro

Author_Institution

Dept. of Electr. Eng., Chiba Inst. of Technol., Japan

Volume

40

Issue

2

fYear

2004

fDate

3/1/2004 12:00:00 AM

Firstpage

778

Lastpage

781

Abstract

A method to calculate the torque of induction motors considering the effects of harmonic core losses is proposed. The negative torque caused by the eddy current and the hysteresis phenomena in the stator and the rotor core is calculated from the time variation of the magnetic field distribution obtained by the nonlinear time-stepping finite element analysis. The calculated negative and total torques agree well with the experimental results. It is clarified that the negative torque is not negligible in the case of the motor with semiclosed slots and that the accuracy of the torque calculation is improved by the proposed method.

Keywords

cores; eddy current losses; finite element analysis; induction motors; machine theory; magnetic fields; magnetic hysteresis; rotors; stators; torque measurement; eddy current; harmonic core losses; hysteresis phenomena; induction motors; magnetic field distribution; negative torque; nonlinear time-stepping finite element analysis; rotor core; semiclosed slots; slot harmonics; slot ripples; stator; time variation; torque calculation; Core loss; Eddy currents; Finite element methods; Induction motors; Magnetic cores; Magnetic fields; Magnetic hysteresis; Rotors; Stator cores; Torque;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2004.824720

Filename

1284530