Adaptive high bandwidth current control for induction machines

For high performance induction machine control, the technique of indirect rotor flux oriented vector control is commonly utilized. The torque performance of this technique is significantly affected by the performance of the current control loops. In this paper a new adaptive high bandwidth current controller for induction machines is presented. The technique is derived and validated through simulation and experimental results. The new architecture is shown to achieve a dead-beat response, with a rise time of one sample period and no overshoot, when the inverter voltage limit is not exceeded. When the voltage limit is exceeded the current response is achieved in a minimum time with no overshoot. It is shown that the new control technique achieves similar dynamic response to the conventional dead-beat control scheme while eliminating parameter sensitivity issues. It is demonstrated that the new algorithm offers higher bandwidth than the commonly used synchronous frame proportional plus integral control technique while maintaining good steady state performance. Index Terms--Adaptive control, current control, current control loops, dead-beat control, dynamic response, indirect RFO vector control, induction machine, synchronous frame, vector control.