A rotor flux oriented scheme of induction machine based on voltage controller

The performance of the induction machine driving system with indirect vector control can easily be influenced by the effects of parameter mismatch and eddy current, which result that the magnetizing component of stator current can´t align with the rotor flux vector, especially in the range of high speed and flux weakening. In order to achieve accurate rotor flux orientation, a novel control strategy based on the voltage controller is proposed in this paper. The relation between the phase voltage of the induction machine and the accuracy of the field orientation is analyzed and a voltage controller is used to eliminate the angle between the d-axis and the rotor flux vector due to the incorrect orientation. The simulation results show that the performance of the driving system in the whole speed region can be improved obviously. So, the robustness of the control system to the motor parameters, especially to the rotor time constant is raised highly.