感应电机低速控制方法

基于模型参考自适应(MRAS)的无速度传感器的转子磁场定向控制广泛应用于感应电机驱动系统,速度辨识系统在零频或极低速时会不稳定。文中分析了辨识在零频或极低速时导致不稳定的原因,通过在传统转子电流和磁通观测器添加激励信号,设计新的自适应观测器,采用Lyapunov方法证明了系统在零频或极低速运行时的稳定性和收敛性。仿真显示了该方案优于传统的MARS方法,提高了低速时转速的渐进跟踪能力,使控制系统具有良好的动静态性能,易于实现。

Control of Indeuction Motor at Low Speed

Based on model reference adaptive system(MRAS),speed sensorless is widely used in the rotor field oriented control induction motor drive system.The speed identification system is unstable at the zero or very low frequency.This paper analyzes the instability reason of the identification at the zero-frequency or very low speed.The design of new adaptive observer is designed by adding the excitation signal to the traditional rotor current and flux observer.And Lyapunov method has proved stability and convergence of the system at the zero frequency or very low speed.Simulation results show that the proposed method is superior to the conventional MARS method and ensure rotor speed of the asymptotic tracking.The control system has good dynamic and static performance,which is easy to be implemented.