TSBC Converter With BESS for DFIG-Based Wind Energy Conversion System

This article proposes the integration of a battery energy storage system in a doubly fed induction generator based wind energy conversion system. A modified triple star bridge cell converter is proposed for the control of doubly fed induction generator and battery energy storage system. The modular structure of the converter facilitates the integration of large energy storage using low rated converters. A median filter is used to segregate the fluctuating component of power generated because of wind speed variation. A control strategy is proposed to mitigate a part of this fluctuation within the rating of the battery energy storage system thereby reducing the fluctuation of power fed to the grid. Wind velocity at an interval of 30 s is obtained from online resources and the performance of the proposed algorithm is evaluated via a simulation study. A wind turbine is emulated in a separately excited dc motor and the performance of the proposed scheme is experimentally validated in a laboratory prototype.