设计了一种在同步旋转坐标系下的无速度传感器感应电机滑模速度和磁通控制方案,并设计了一种收敛速率可调的闭环滑模磁通观测器。Lyapunov稳定性理论推导和仿真结果均证明了该控制策略和磁通观测器对参数摄动和不确定因素有很强的鲁棒性。为了削弱变结构控制中的抖振现象,采用饱和函数来代替符号函数。在转速观测器中加入在线估计负载转矩环节,使得转速观测器对负载转矩变化具有良好的鲁棒性。在电机参数和负载发生剧烈变化的情况下,分别利用该控制策略和精确反馈线性化控制方法进行了对比仿真。仿真结果验证了该控制策略与观测器的有效性。
A sliding-mode speed and flux control strategy of the speed sensorless induction machine in synchronous rotating coordinate and a closed-loop flux observer with adjustable convergence rate are presented. The stability analysis based on Lyapunov theory and the simulation results both verified the robustness of the control scheme and the flux observer against the parameter variation and the uncertainties. In order to eliminate the chattering phenomenon in sliding-mode control, the saturation function is adopted to replace the sign function. The load torque is estimated online within the speed observer, such that the robustness of the speed observer against the variation of the load torque is achieved. Under the condition of drastically changed induction machine parameters and load torque, the simulations of the control strategy and exact feedback linearization method are performed respectively. The high performance of the control scheme is verified via simulation results.