无轴承永磁薄片电机的新型单绕组结构及其精确控制

Accurate Radial Suspension Force Control of Single Winding Bearingless Permanent Magnetic Slice Motor with New Structure

针对双绕组无轴承永磁薄片电机绕组间绝缘要求高、槽满率低、电机漏磁大等缺点,提出了一种新型单绕组无轴承永磁薄片电机(M-BPMSM)结构,在每相绕组端部通入转矩电流,同时在绕组中点处注入悬浮力电流,实现薄片转子的旋转和悬浮。阐述了M-BPMSM的悬浮力产生原理,推导了其径向悬浮力的精确数学模型。在该模型的基础上建立了一种悬浮力双闭环补偿控制策略,当电机负载变化导致悬浮力幅值和方向改变时,使用该策略可以对径向悬浮力进行补偿,实现悬浮力的精确控制。利用MATLAB软件构建了仿真系统,仿真结果表明:采用悬浮力双闭环补偿控制策略对M-BPMSM进行控制,径向悬浮力具有较高的控制精度和较快的响应速度,且具有良好的动、静态性能。

To solve problems of the conventional bearingless permanent magnetic slice motor with double windings, such as high insulation requirement, low filling ratio, serious flux leakage, a novel structure of single- winding bearingless permanent magnetic slice motor was proposed. This structure has only single winding which was for rotation, the middle-point terminals of this winding were extracted to inject radial suspension force current （ M- BPMSM）. The principle and structure design of M-BPMSM were investigated and the accurate mathematical model of radial suspension force was deduced. Based on the model above, a double closed loop control strategy in radial suspension force subsystem was put forward which could compensate for the radial suspension force changed because of the load sudden change of motor. The simulation model based on MATLAB was constructed and the result showed that the proposed radial suspension force control method could improve the control accuracy and dynamic performance of suspension force of M-BPMSM.