A modified Control Strategy of Neutral-Point Clamped Converter-Fed PMSM Drives with Engergy Storage Systems

This paper proposes a modified control strategy for three-phase three-level neutral point clamped (NPC) converter-fed Permanent Magnet Synchronous Motor (PMSM) drive in the application of Energy Storage Systems (ESS) using single-carrier modulation. The increasing demands in renewable energy (RE) sources has attracts many research interests in recent years. The integration of different types of distributed DC systems has become a challenge for high power application. In this study, the NPC converter is employed for DC-AC conversion, with two ESS units serving as individual DC power supplies. The main focus is on simplification of the control and modulation technique for the NPC converter, which operates with individual ESS units having imbalanced SOC and voltages. The aim is to achieve balanced SOC between the ESS units and maintain high-quality AC output. Additionally, utilizing single-carrier modulation reduces the complexity of the control when a digital signal processor (DSP)-based platform is employed. Simulation results verifies effectiveness of the proposed method.