基于滑模观测器的单绕组多相无轴承电机无位置传感器控制

Position Sensorless Control Based on Sliding Mode Observer for Multiphase Bearingless Motor with Single Set of Windings

针对单绕组多相无轴承电机的特点,讨论了此类电机中悬浮平面电流对电机转子位置带来的扰动,建立了基于滑模观测器的检测模型和控制算法,实现了单绕组多相无轴承电机的无转子位置传感器运行。文中采用饱和函数代替开关函数,并设计了随转速变化的低通滤波器,取得了良好的观测效果。该方法克服了传统基于电机模型的无位置传感器控制方法对电机参数的依赖性,抑制了由无轴承电机悬浮平面耦合带来的固有扰动,提升了无轴承系统的鲁棒性。实验结果表明系统采用该观测器进行转子位置及速度观测后,具有较好的静、动态性能,验证了滑模观测器在单绕组多相无轴承驱动系统无位置传感器中应用的正确性和可行性。

In this paper, the disturbance of the rotor position caused by the current of the suspension plane was discussed in a multiphase permanent magnet bearingless motor system. The detection model and the control algorithm were established based on a sliding mode observer. To ameliorate the system performance and identification accuracy, saturation function and low-pass filter with a variable cut-off frequency were designed. Comparing with conventional sensorless control algorithm based on the back electromotive force（EMF）, the proposed scheme is insensitive to motor parameters, and it could inhibit the innate disturbance caused by coupling and enhance the robustness of the bearingless system. The experimental results verify the accuracy and feasibility of the proposed sensorless control scheme based on the sliding mode observer in the multi-phase bearingless motor with single set of windings.