Variable-Speed Control of a Six-Phase Induction Machine using Predictive-Fixed Switching Frequency Current Control Techniques

Model predictive control method has been recently introduced as an alternative to inner current controllers of multiphase drives using rotor field oriented control methods. Model predictive controllers are distinguished by a variable switching frequency which causes noise, large voltage and current ripples at low sampling frequency. Therefore, this paper proposes a variable-speed control for six-phase induction motor drives by using an inner loop of predictive-fixed switching frequency current control scheme. Experimental results are provided in order to prove the feasibility of the proposed control technique, considering mean squared error as well as the total harmonic distortion of the stator currents as figure of merit. The efficiency of the proposed control could be verified by applying the nonparametric Mann-Whitney statistical test on the experimentally obtained data.