Frequency control by BESS for smooth Island transition of a hydro-powered microgrid

Journal article, 2024

This paper develops a frequency control strategy for a battery energy storage system to facilitate the smooth island transition of a hydro-powered microgrid during unplanned grid outages. The proposed frequency control strategy uses a PI-based droop controller, where the tuning of the controller accounts for the limitations in the power response of a hydro generator and the required frequency quality of the microgrid. The effectiveness of the frequency control strategy is verified in Simulink using phasor simulations, and it is further validated in laboratory tests. The results demonstrate that the proposed PI-based droop and its tuning strategy fulfill the desired frequency quality requirement of the hydro-powered microgrid without over-dimensioning the size of the storage capacity as compared to the traditional proportional droop controller.