基于MRAS的无速度传感器异步电机控制

为研究无速度传感器直接转矩控制系统中对速度的估算和控制，建立了一种基于模型参考自适应（MRAS）系统原理的速度磁链自适应观测器。它以定子电流和定子磁链为状态变量，构建全阶观测器为可调模型，电机本身为参考模型，把磁链观测和速度辨识结合起来，直接把定子磁链观测值应用于直接转矩控制算法中，定义了李亚普诺夫函数，并根据其稳定性理论确定了速度自适应律。通过Matlab／Simlink软件进行了仿真。仿真结果表明，该系统对电机定子磁链的观测精度高，速度运算较准确，在全速范围内能保持较高的性能。

Induction motor's speed sensor less control based on MRAS

For the study of the speed estimate and control in the speed sensor less direct torque control system, a new speed-adaptive flux observer based on model reference self-adapt control system theory was designed. The observer was regarded as adjustable model which used the stator current and the stator flux as state variable, motor itself was regarded as reference model. The observation of flux and estimate of speed were combined at the meantime. The observered flux was applied to direct torque control system. The speed adaptive scheme of speed estimation was obtained utilizing Lyapunov＇s stability theory. This approach was implemented on Matlab/Simulink software. The simulation results show that the method gives satisfying estimation of stator flux and rotor speed in the whole speed range.