Performance Evaluation and Techno-Economic Analysis of Modular Multilevel STATCOM with Hybrid Storage for Renewable Power Dominated Grids

The increase in renewable power injection into the existing ac network has affected voltage and frequency stability. This creates the need for both active and reactive power support systems at the Common Coupling Point (CCP) of a renewable power generating station. Considering the aforesaid requirements, a distinct configuration using a Modular Multilevel Converter (MMC) with Hybrid Storage System (HSS) has been recommended in this paper. These kinds of systems are termed as “Statcom Embedded with Storage System”(SESS). The SESS helps to pump invariable power into the grid by absorbing fluctuating components of active power generated by the renewable power generating plant. Apart from this, provides ancillary services at CCP like, voltage regulation and compensation for negative sequence currents, and ride through capability during the faults in the ac system are to be provided by SESS. The required control methods to operate the proposed configuration for the aforesaid necessities are discussed in this manuscript. The economic advantage of the proposed configuration in comparison to other multilevel topologies has been identified using a techno-economic study and it is presented. The competency of the recommended configuration for SESS application along with its control is verified through PSCAD/EMTDC simulation and the results show its efficacy.