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 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 paper 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. In this concept in future by increasing the levels of Multilevel Inverter we improve the power quality.

G. SIVA NAGESWARA RAO,SHAIK. MABHU JANI."Power Quality Step up Using Modular Multilevel Converter for Renewable Energy Source". International Journal of Computer Engineering In Research Trends (IJCERT) ,ISSN:2349-7084 ,Vol.1, Issue 06,pp.520-523, DECEMBER - 2014, URL :https://ijcert.org/ems/ijcert_papers/V1I627.pdf,

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