Control Strategies of Battery Energy Storage Systems for Smoothing Wind Power Fluctuations

Integrating a wind farm with a battery energy storage system (BESS) could improve the intermittence and randomness of the output power of the wind farm, and hence reduce the negative impacts on the security and economics of the power system concerned. Given this background, an improved control strategy is first proposed with the interactions between the current charging/discharging status of BESS and the state of the charge (SOC) constraints at the next time slot taken into account. Subsequently, an optimal control strategy is presented with an objective of minimizing the probability of violating the limits of the combined output power fluctuations from the cogeneration system. A highly efficient solver, AMPL/CPLEX, is next employed to solve the optimization model. Finally, a cogeneration system composed of a large wind farm and a BESS is employed to demonstrate the proposed strategies. Simulation results show that both the improved control strategy and the optimal control strategy for the BESS can effectively mitigate the combined output power fluctuations of the cogeneration system.