基于无速度传感器的异步电机调速系统，运用电流来合成磁链，控制方法是转子磁链定向。采用电流滞环控制，电网电压380V，转矩最大达30N.m。波形效果不错。-Based on speed sensorless induction motor speed control system, using current flux synthesis method for controlling the rotor flux orientation. Use current hysteresis control, grid voltage 380V, maximum torque of 30N.m. Waveform good results.