基于改进磁链观测器的感应电机转速辨识

感应电机电压模型转子磁链观测器由于其算法简单而得到广泛应用,但低速时由于定子电阻压降明显使得测量误差严重影响观测精度,纯积分的应用还存在直流偏置和初始值问题。本文提出了一种改进电压模型转子磁链观测器,引入定子磁链的电流模型和电压模型之间的误差对定子感应电动势进行补偿,理想积分环节采用新型改进低通滤波器代替,再由定子磁链的电压模型推导出转子磁链的电压模型。在此基础上,通过得到的转子磁链对感应电机的转速进行辨识。仿真和实验表明新算法改善了转速辨识的动静态性能,尤其改善了低速时的转速辨识性能。

Speed Identification for Induction Motor Based on Improved Flux Observer

The voltage model of rotor flux observer is applied,because it is simple.But the model is extremely sensitive to measurement errors at low speed because the voltage drop of stator resistance and the pure integrator of the voltage model has some disadvantages like DC offset and initial value problems.In this paper,an improved rotor flux observer is presented.The stator electromotive force is compensated by introducing the errors between the current model and the voltage model of the stator flux.The ideal integrator is replaced by the new modified low-pass filter.The voltage model of rotor flux is deduced from the voltage model of stator flux.The speed is identified based on the improved rotor flux observer.Simulation and experimental results verify that this strategy improves the dynamic and static performance of the speed identification,especially at low speed.