Model predictive current control of a five-phase induction motor

Model predictive control (MPC) of a multiphase induction motor drive is elaborated. A vector controlled, inverter fed five-phase induction motor is chosen as the platform for verification of the developed algorithm. Indirect rotor field oriented control (IRFOC) is implemented using MPC algorithm for current control, with the idea of achieving fast current response and current ripple minimization. The emphasis in the paper is placed on the optimization of the weighting factor of the x,y-plane current errors in the MPC cost function. For this purpose all 32 possible switching states of the inverter are considered as available input and the impact of the weighting factor on the RMS of the ripple of stator current components and on the triggered inverter states is investigated as a function of the fundamental frequency. It is shown that at different stator fundamental frequencies different weighting factors lead to minimum current ripples. Using weighting factor values, determined in this manner, speed, current and torque performance, achieved using MPC within the IRFOC, are illustrated.