异步电机的精确控制和速度辨识是交流传动系统中重要问题。在该仿真系统中，电机转速采用易于检测的电机定子电压和电流得到转速MRAS辨识算法来估算。由于速度辨识算法中电压模型的纯积分环节会引起的误差积累和漂移问题，采用改进积分型转子磁链估算模型来解决。-The precise control and the speed identification of AC motor are the very important issues on AC drive system.In this system, induction motor is controlled by the direct torque control, stator flux is estimated by u-n model observer that is effective in the full range of speed, motor speed is estimated by MRAS speed identification algorithm that is depended on the voltage and the current of motor stator easily detected. The modified integral rotor flux estimation model is used to solve the problem that the normal model can be affected by the error accumulation and drift of integral calculation in the voltage model of conventional speed identification algorithm.