基于滑模变结构的无轴承异步电机控制研究

Research on bearingless induction motor control based on sliding mode variable structure

针对PI控制难以满足负载扰动时无轴承异步电机高品质运行的要求,文中提出了一种滑模转速控制器和负载转矩扩展滑模观测器相结合的无轴承异步电机控制策略。该控制策略利用转速误差的积分环节,并将时变项引入滑模面,设计了滑模转速控制器。以负载转矩和电机转速为观测对象设计了扩展滑模观测器,将负载转矩观测值前馈补偿到滑模转速控制器中。仿真和实验结果表明,该控制策略可对负载转矩进行准确、快速追踪,有效抑制了系统的抖振,提高了系统的抗负载扰动能力和鲁棒性。

It is difficult for the PI control to meet the high quality operation of the bearingless induction motor（BIM） when the load disturbance occurs, so a control strategy of the bearingless induction motor combining sliding mode speed controller with load torque extended sliding mode observer is proposed. A sliding mode speed controller is designed, which adopts the integral term of speed error and the time- vatying term. The extended sliding mode observer is designed with the rotational speed and load torque as the state variables. And then the observed load torque is compensated to the sliding mode speed controller. The simulation and experimental results show that the proposed scheme achieves accurate and fast tracking of the load torque, effectively suppresses the chattering and improves the robustness of the system. The control system has better static and dynamic performance.