Abstract:Due to the unbalanced magnetic pull and special environment in large submersible motors, the excitation frequency for air-gap is close to the rotor natural frequency, and the sub-critical speed may be around the rated speed. Thus the state is prone to the sub-critical rotor vibration, endanger the safe operation of the motor, and even cause an accident. In this paper, the engineering electromagnetic field theory is quoted. The calculation model of eccentricity is built. The electromagnetic force for air-gap between stator and rotor in submersible motors is deduced, and based on which, the relation between excitation frequency for electromagnetic force and natural frequency combining the FFT is obtained. Finally the 3D stress model for stator and rotor is built respectively and the rotor deflection is obtained using the analytical-finite method. Through building the 2D electromagnetic field finite model, the relations among sub-critical speed, rated speed, eccentricity, diving depth, time are discussed. The investigations in this paper support both theoretical basis in reliable operation of the machine and references in fault diagnosis of large submersible motors.
鲍晓华,李福英,方勇,王汉丰,程志恒,狄冲,梁娜. 大型潜水电机混合偏心时转子副临界振动的研究[J]. 电工技术学报, 2015, 30(6): 142-149.
Bao Xiaohua,Li Fuying,Fang Yong,Wang Hanfeng,Cheng Zhiheng,Di Chong,Liang Na. Sub-Critical Speed Vibration of Rotors for Large Submersible Motors with Mixed Eccentricity. Transactions of China Electrotechnical Society, 2015, 30(6): 142-149.
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