Optimal Size of Battery Energy Storage and Monotonic Charging/Discharging Strategies for Wind Farms

This paper focuses on the development of a monotonic charge/discharge strategy to optimize the capacity of a large-scale battery energy storage system (BESS) integrated with a large wind farm to smooth out the intermittent wind farm output for effective power dispatch to the electricity grid. Since a large-scale BESS is rather expensive, adopting such strategy for optimal sizing of the BESS has become critically important. The paper proposes a constraint-based monotonic charge/discharge strategy for multiple batteries of a BESS and determines the optimal capacity of each individual battery satisfying a set of given operating constraints. The effectiveness of the strategy is confirmed with data analysis taken from an actual wind farm. The strategy is generic enough to be applicable to other intermittent generation sources such as solar PV farms.