一种用于异步电机无速度传感器控制的自适应滑模观测器

Adaptive sliding mode observer based sensorless control system of induction motor

针对异步电机无速度传感器中存在的对参数变化鲁棒性差的问题,研究了一种基于自适应滑模观测器的异步电机无速度传感器的矢量控制方案。自适应滑模观测器根据电机静止坐标系下的数学模型构造了转子磁链观测器,定子电流观测值与实际值的误差构成观测器的滑模面,在滑模运动下该观测器的观测值最终趋近于实际值,从而实现转子磁链的估计。电机转速由自适应方法估算得到,滑模观测器的稳定性可由李雅普诺夫稳定性证明。与其他方案相比,该方法的优点在于实现简单,对参数变化具有鲁棒性。仿真和实验对控制方案的正确性和可行性给出了验证,该观测器可以实现对转子磁链和转速的观测,且在负载扰动和给定转速变化的情况下该滑模观测器具有鲁棒性。

For the problem of poor robustness to parameter change of induction motor speed sensorless control, an adaptive sliding mode observer based sensorless vector control method is presented for induction motor in this paper. The rotor flux observer was constructed on the basis of the state equation in static coordinate system. The sliding mode surface of the observer was derived by the error of the estimated stator current and the actual stator current. With the sliding motion, the estimated values were reaching the ac- tual values finally, thus realizing the estimation of the motor rotor flux. The motor speed was obtained by adaptive theory. The Lyapunov stability theory guarantees the stability of the presented observer. Compared with other methods, adaptive sliding mode observer in this paper is superior in implementation easily and better robustness to the motor parameters deviations. The method has been simulated and implemented u- sing the TMS320F2812 fixed-point DSP controller. Simulation and experiment results verify its feasibility and effectiveness, and under the condition of the load disturbance and the given speed change the sliding mode observer has certain robustness.