An Efficient Predictive Current Control Strategy for a Four-Level Open-End Winding Induction Motor Drive

Abstract

Thisarticle proposes a newpredictive current control (PCC) strategy for a dual-inverter fed four-level (4-L) open-end winding induction motor drive (OEWIMD).Theindividualinvert ers of the dual-inverter system are operated with dc-link voltages, which are in the ratio of 2:1. In general, the PCC for the 4-L OEWIMDrequiresthe evaluation of all of the 37 available voltage vectors (VVs) to select the optimal one. An improvised PCC is proposed in this article, wherein the inverter with lower dc-input voltage is clamped, while the other inverter is switched around it. Animportant feature of the proposed PCC is that it evaluates only f ivecandidate VVstodeterminetheoptimalvector.Thesimulation and the experimental results reveal that the performance of the proposed PCC technique is superior to the conventional PCC in terms of voltage and current total harmonic distortion (THD), torque-ripple, and total drive loss. Furthermore, the proposed PCC results in the reduction of the computational burden on the controller. Also, as the reduction of switching frequency is inherent in the proposed PCC strategy, there is no requirement to add an additional constraint to reduce it in the cost function.