Model Measurement and Identification of Flexible Rotor Suspended by Electromagnetic Bearing

doi:10.3901/JME.2016.08.016

Abstract

Abstract: Electromagnetic bearings(EMBs) possess several attractive advantages, such as no friction, no need of lubrication, and the ability of long-term high speed running. Thus EMBs are widely applied in high-speed rotating machineries and rotating machineries under special environments. The mathematical model of an EMB system plays an important role in analyzing the whole system and designing the controller. Due to many practical reasons, the computational models are usually not precise enough. Therefore, measurement is an important means to obtain the model of an EMB system. A measurement and identification method is proposed, the closed-loop frequency response model via swept-sine technique is measured by this method, then the model is transformed to the open-loop frequency response model, finally the transfer function model will be identified. The proposed method is validated by experiments on a real EMB system.

Key words: electromagnetic bearing, flexible rotor, swept-sine experiments, system identification

CLC Number:

TH133

SUN Zhe, ZHAO Jingjing, SHI Zhengang. Model Measurement and Identification of Flexible Rotor Suspended by Electromagnetic Bearing[J]. Journal of Mechanical Engineering, 2016, 52(8): 16-22.

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