A Novel Space-Vector Current Control Based on Circular Hysteresis Areas of a Three-Phase Neutral-Point-Clamped Inverter

This paper presents a novel space-vector current-control strategy for three-phase neutral-point (NP)-clamped inverters. The main task of this control technique is to force the actual current vector to reach the reference current vector. This original strategy consists in defining three circular hysteresis bands around the error vector. Then, according to the location of this error vector, a selection process of the next applied vector is used to minimize the error vector. The NP voltage is balanced by using the redundant inverter switching states. Simple lookup tables are required for area and sector detection, as well as for vector selection. The performance of the proposed control technique is demonstrated through simulation and experimental investigations.