电磁轴承具有无摩擦、不需润滑、可长时间高速运行等优点,广泛应用于高速旋转机械、特殊工作环境旋转机械等领域。电磁轴承系统的数学模型对于系统分析和控制器设计具有重要意义,但受各种因素影响,计算模型误差较大,往往不能满足设计调试要求。因此,现场测试是获取系统模型的重要手段。提出一种电磁轴承支承的柔性转子的测试与建模方法,该方法通过正弦扫描试验获取闭环系统频响模型,通过变换得到开环频响模型,然后通过辨识得到转子传递函数模型,并在实际系统上验证了提出的方法。
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.
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