针对感应电动机调速系统综合运用了多种控制手段 ,在内环采用滑动模控制以实现感应电动机转矩和磁链的解耦 ,外环采用锁相环 (PLL)控制使被控系统具有高稳态精度 .而在动态过程中则引入了模糊滑动模控制(FSMC) ,保证了系统的快速性和鲁棒性 . Aiming at the speed control system of induction motor, a variety of control methods are used synthetically. Sliding mode control is adopted in the inner ring to decouple the induction motor torque and flux linkage. The outer ring is controlled by phase locked loop (PLL) to make the controlled system have high Steady-state accuracy, while fuzzy sliding mode control (FSMC) is introduced in the dynamic process to ensure the rapidity and robustness of the system.