Determination of optimal size of battery energy storage system (BESS) for a renewable power based microgrid

摘要

A battery energy storage system (BESS) plays a crucial role in the proper operation of a microgrid. Larger the size of the BESS, smaller is the microgrid operating cost, but higher is the BESS's capital cost. Thus, a compromise between the operating cost and capital investment is to be reached for determining the optimal BESS size. The present work focuses on finding the optimal power and energy rating of a BESS in a microgrid. In this work, a non-trivial network with proper network parameters and network loss has been considered. A simple energy management strategy is proposed to determine the optimal dispatch strategy in the microgrid when the day-ahead forecasts of load, wind power, and solar power are available. Optimal sizing of three types of batteries, namely lithium-ion, sodium-sulfur, and lead-acid are considered. Simulation studies on a twelve-node distribution network are presented.