应用无源性控制方法研究了在负载转矩和转子电阻为未知时变情形下感应电机期望转矩的跟踪控制问题。基于感应电机的Euler-Lagrange（E-L）模型，通过设计控制器、期望轨道、期望转矩、转子电阻估计器、负载转矩估计器、转子状态观测器，在理论上证明了可以实现对任意时变期望转矩的渐近跟踪，以及对负载转矩和转子电阻的快速估计。基于MATLAB/Simulink的仿真结果，证明了理论结果的正确性、有效性和高性能。

The expected torque tracking control problem of induction motor based on passivity principle is analyzed in case of arbitrary unknown time varying load torque and rotor resistance. The mathematical model of induction motor in Euler-Lagrange (E-L) equation is built. The controller, the expected orbit, the expected toque, the rotor resistance estimator, the load torque estimator and the rotor state observer are designed. Through these processes, it is theoretically proved that the expected torque and speed can be tracked asymptotically and the load torque and rotor resistance can be estimated rapidly. The MATLAB/Simulink simulation results also show the correctness, validity and excellent performance of the proposed method.