永磁无刷直流电动机场路耦合运动时步有限元分析

提出一种适用于永磁无刷直流电动机的场路耦合运动时步有限元分析方法，解决了电机在非正弦供电时的场路耦合分析问题。电路中考虑了开关元件换流重叠过程和绕组中点的电位波动。给出了控制电路与电磁场方程耦合的时步有限元单元分析方法，采用改进的有限元运动边界处理方法--插值运动边界法解决转子运动问题。应用上述模型对1台无刷直流电动机的进行分析，计算结果和样机的实测波形吻合。该方法也适用于其他非正弦供电电机的场路耦合有限元分析。

Field Circuit and Movement Coupled Time Stepping Finite Element Analysis on Permanent Magnet Brushless DC Motors

Load disturbance leads to rotor eccentricity of bearingless motors in practical operation,which will influence the control performance of stable suspension. It is the focus in studies of bearingless motors to levitate the rotor stably by directly and effectively controlling rotor eccentric displacement. Firstly,Maxwell forces of bearingless motors and the relationship between eccentric displacement and radial levitation force were analyzed. Then,based on the principle of controllable radial levitation force,a new approach to control rotor eccentric displacement was proposed. This approach directly controls rotor eccentric displacement of bearingless permanent magnet-type synchronous motors by using the control of rotor flux orientation. By applying this approach,a control system was also designed. The simulation results show that this approach is effective in improving the static and dynamic performance of stable suspension of bearingless motors,and this approach realizes direct control for rotor eccentric displacement.