基于转矩绕组无功功率MRAS的无轴承异步电机无速度传感器矢量控制系统

Speed-sensorless Vector Control System of Bearingless Induction Motor Based on Reactive Power MRAS of Torque Winding

针对无轴承异步电机运行中转速辨识问题,提出了一种基于转矩绕组无功功率的模型参考自适应系统(MRAS)的无速度传感器矢量控制方法。该方法将反电动势和定子电流叉乘得到的瞬时无功功率作为可调模型,建立转速与转矩绕组无功功率的关系式,克服了传统MRAS方法转速受积分环节以及定子电阻变化的影响,实现对转子转速的在线辨识。理论分析和计算机仿真结果表明,提出的控制方案能在高速、低速、负载扰动等不同工况下准确辨识转子速度,实现无速度传感器方式下无轴承异步电机的稳定悬浮运行,具有令人满意的静动态特性和较强的鲁棒性。

Aiming at rotor speed identification of bearingle^s induction motor, a novel speed-sensorless vector control scheme of bearing- less induction motor based on reactive power model reference adaptive system （MRAS） of torque winding was proposed. Using the in- stantaneous reactive power calculated from back-electromotive force multiplied by the stator current as the adjustable model, and estab- lishing the relationships between the speed and the reactive power of torque windings, the presented method eliminated the integration process and the effect of stator resistance in traditional MRAS method, and then realized the on-line rotor speed identification. Simula- tion results showed that the rotor speed of bearingless induction motor can be precisely inspected in low and high speed operation with load disturbances and the stable sensorless suspension operation can be achieved with good dynamic and static performance by using the proposed method.