Abstract：Large submersible motors are widely used for water supply and drainage of industry, municipal wastewater treatment, etc. However, mechanical failures such as bent shaft and bearing damages will result in air-gap eccentricity. Small air-gap eccentricity gives rise to air-gap field distortion, increase in vibration and current fluctuation. Critical air-gap eccentricity may lead to a rub between the rotor and stator, or breakdown of the driven equipment. This paper deduces the magnetic flux expression of a stator tooth in a dynamic eccentric submersible motor, and analyzes eccentricity related frequencies in tooth magnetic field. The basic idea is that the air-gap magnetic flux is determined by the air-gap permeance and magnetomotive force, while the air gap magnetic flux near the tooth totally passes through the stator tooth. Accordingly, a way of air-gap eccentricity detection in large submersible motors is proposed in this paper. Finally, the theoretical analysis is validated by finite element simulation. This paper also explores the relation between magnitude of harmonic and degree of eccentricity, providing the precise air-gap eccentricity detection of induction motors.
鲍晓华, 吕强, 王汉丰. 基于齿部磁场分析的大型潜水电机气隙偏心故障研究[J]. 电工技术学报, 2016, 31(8): 90-95.
Bao Xiaohua, Lü Qiang, Wang Hanfeng. Study on Air-Gap Eccentricity Fault in Large Submersible Motors with Tooth Magnetic Field Analysis. Transactions of China Electrotechnical Society, 2016, 31(8): 90-95.
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