介绍了三自由度交流混合磁轴承的结构示意图和工作原理。通过对其永磁体产生的偏置磁场的利用率以及径向悬浮力大小的分析,提出了永磁体与直流电组合偏置的方法。利用等效磁路法对组合偏置磁轴承进行了磁路分析并建立了悬浮力数学模型,并对组合偏置磁轴承进行了有限元分析,理论计算与仿真得出三自由度组合偏置磁轴承消除了悬浮力上限,减小了磁轴承的体积,更有利于磁轴承在高速电主轴、高速飞轮储能等系统中的应用。
The structure and the theory of 3-DOF AC hybrid magnetic bearing(HMB) were introduced. Through the analysis of the utilization of HMB's biased flux and the radial suspension force, the method of permanent magnet and electromagnetism combined biased flux was proposed. The magnetic circuit was analyzed by equivalent magnetic circuit method and the mathematical model of suspension force was established. The magnetic field distribution and suspension force were calculated and simulated by using finite element analysis. Both of theoretical calculation and simulation of 3-DOF combined biased magnetic bearing could prove the suspension force limit was eliminated and reduce the volume of magnetic bearing. This was advantageous to the application of magnetic bearings in high speed motorized spindle system, flywheel energy storage system and so on.