磁悬浮飞轮轴向混合磁轴承参数设计及分析

Parameter Design and Analysis on Axial Hybrid Magnetic Bearing Using in Magnetic Suspension Flywheel

磁悬浮飞轮系统是空间飞行器实现高精度姿态控制常用的执行机构,磁轴承作为磁悬浮飞轮中的重要组成部分,要求其具有结构紧凑、体积小、重量轻、功耗低、效率高等优点。提出了一种新型轴向混合磁轴承,该磁轴承采用永磁体提供静态偏置磁场,功耗低、体积小,尤其适合在磁悬浮飞轮系统中应用。在阐述磁轴承结构和工作原理基础上,采用等效磁路法推导出磁轴承悬浮力数学模型,得出了磁轴承最大承载力数学表达式;给出了详细的参数设计方法,设计了轴向承载力400 N的磁悬浮飞轮轴向磁轴承;采用有限元方法对其磁路及最大承载力进行了仿真计算和分析,并进行了试验研究。理论和试验结果证明了数学模型的正确性和参数设计合理性。

A magnetic suspension flywheel system is the actuator of spacecraft in high accurate attitude control, which requires the employed magnetic bearing with advantages of compact structure, small volume, light weight, low power loss, high efficiency and so on. A novel axial hybrid magnetic bearing for magnetic suspension flywheel is proposed, and the bias magnetic flux is provided with a permanent magnet ring. The cost and the total volume of this structure can be reduced, which is especially suitable for the magnetic suspension flywheel system. The structure and working principle of the axial magnetic bearing are explained, the mathematical equations of magnetic suspension forces of the axial hybrid magnetic bearing are derived by using equivalent magnetic circuit, the mathematical expressions of the maximum bearing capacity is obtained, the process of parameter design is presented in detail and an axial hybrid magnetic bearing with bearing capacity 400N is designed. The flux and maximum bearing capacity of the hybrid magnetic bearing are simulated and analyzed by using finite element analysis software, and the experiments have been carried out. The results of theory and experiment have shown that the mathematical model is correct and parameter design is reasonable.