A Control Method for Asynchronous Motor Based on Stator Current Vector Orientation

The stator flux model is different at high speed and low speed for the direct torque control (DTC), so the structure of DTC system is complex. Aiming at this issue, a new scheme of induction motor drive is proposed. The core idea is controlling the angle between the stator current vector and the rotor flux vector. It doesn't need the stator flux model. The system will obtain quick torque response by this control strategy. This new method can achieve wide speed range including zero speed. Very few parameters require to be adjusted and the system structure is very simple contrast to the conventional DTC system. It is robust to the variations of motor parameters. Simulation results have confirmed the effectiveness of the presented scheme