Modular Multilevel Converter D-STATCOM for Grid Connected Small Wind Turbines

Abstract

Multilevel inverters have received more attention in industrial application, such as motor drives, FACTS devices and renewable energy systems, etc. Primarily multilevel inverters are known to have output voltages with more than two levels. A modular multilevel converter (MMC) is one of the next-generation multilevel converters intended for high or medium-voltage power conversion without transformers. Compared with the existing multilevel converters, one of the most desirable advantages offered by MMC may be its ability to process both active power and reactive power with its terminals directly connected to directly high-voltage networks. D-STATCOM (Distribution Static Compensator) is a shunt device which is generally used to solve power quality problems in distribution systems. D- STATCOM is used in correcting power factor, maintaining constant distribution voltage and mitigating harmonics in a distribution network. In this project MMC D-STATCOM inverter controls the DC link voltage as well as the active and reactive power  transferred between the  renewable energy source, specifically wind turbine, and the grid in order to regulate the power factor (PF) of the grid regardless of the input active power from wind turbine. The proposed topology developed by using Matlab/simulink software. In extension to the base paper we can compare the proposed MMC type of inverter with the 9 level MMC inverter.