Performance assessment of a solar-powered three-phase modular multilevel converter with capacitor voltage balancing

Abstract

Solar photovoltaic (PV) systems are becoming increasingly popular across the world, and the Modular Multilevel Converter (MMC) architecture emerged as an appealing option for PV integration. The MMC topology has been conceived to alleviate the inconveniences of traditional multilevel converters, such as the higher-order level capacitor balance problem, the necessity for power filters and interface transformers. Because of its inherent benefits, MMC is used as the interface between diverse energy resources. Here, the PV is integrated with maximum power point tracking into the three phase three level MMC. When it comes to maintaining output power quality, modulation methods are significant. The proposed capacitor voltage balancing algorithms use phase disposition pulsewidth modulation (PDPWM) and space vector modulation (SVM) schemes to ensure the balancing of the capacitors in each sub-module. The MATLAB/Simulink simulation is performed and the effectiveness of the control approaches is evaluated.