Predictive power control of induction motor drives with improved efficiency

Abstract

The performance of predictive current control (PCC) of induction motor (IM) drives is sensitive to the accuracy of the rotor flux angle estimation. In addition, predictive torque control (PTC), prioritizes control objectives by weighting factor in the cost function. It is tedious work to find a suitable weighting factor. In order to overcome these issues, a predictive power control (PPC) of IM drives is proposed in this paper. It directly controls the instantaneous output power of IM and does not require weighting factor and rotor flux angle estimation. This is achieved by the use of instantaneous power theory. The decoupling control of torque and rotor flux can be realized by controlling the output active and reactive power. The proposed method is easier to implement than PCC and PTC. To improve output efficiency, an output efficiency optimization strategy is proposed based on PPC. This is realized by adding the weighted output efficiency term into the cost function directly. Moreover, in order to get a better steady-state performance, an optimization strategy is proposed according to extend the output voltage vectors. Finally, the experimental and real-time hardware-in-the-loop (HiL) results validate that the proposed strategy is easier to implement and could optimize the output efficiency of the motor.