Inhibition of Bearing Currents in Frequency Variable Motor Based on Electromagnetic Shielding
Bai Baodong, Wang Yu, Chen Zhixue, Wang Xiaochuan
Theory and Common Technologies of Modern Electrical Equipments Key Lab Special Electric Machines and High Voltage Apparatus Key Lab National Education Ministry and Liaoning Province Shenyang University of Technology Shenyang 110870 China
Abstract：Two methods to suppress the bearing current, i.e. the electromagnetic shield slot wedge within the machine and the bearing current short circuit ring, are analyzed. The theory of the electromagnetic shield slot wedge is reviewed. And the element finite model is established to evaluate the shield effectiveness for high frequency electromagnetic field. The theory of the bearing current short circuit ring is introduced. Finally, the experimental platform is set up to evaluate the shield effectiveness. The test motor is a 3 kW/4-pole variable frequency motor. The bearing currents of the motor with the electromagnetic shield slot wedge and the bearing current short circuit ring are measured respectively. According to the experiment results, the suppression effectiveness is evaluated.
白保东, 王禹, 陈志雪, 王晓川. 基于电磁屏蔽法变频电机轴承电流抑制研究[J]. 电工技术学报, 2016, 31(7): 33-39.
Bai Baodong, Wang Yu, Chen Zhixue, Wang Xiaochuan. Inhibition of Bearing Currents in Frequency Variable Motor Based on Electromagnetic Shielding. Transactions of China Electrotechnical Society, 2016, 31(7): 33-39.
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2016, Vol. 31 
