Optimal control of battery energy storage system integrated in PV station considering peak shaving

A novel control strategy for battery energy storage system (BESS) which is integrated within photovoltaic power station is presented in this paper. Normally the function of BESS is to mitigate the power fluctuation of PV to meet the requirements of dispatch center. In this paper, besides PV fluctuation smoothing, peak power shaving is also considered in the control strategy of BESS, which means part capacity of BESS is idle when fluctuations of PV power is small and not all BESS capacity is needed, and then on basis of time-in-use electricity price, this part of idle BESS can take part in peak shaving to earn extra benefits. Thus, the size-limited BESS can be fully utilized and meanwhile extra benefits from peak shaving can be achieved. Using actual PV power data, the proposed strategy is verified and the simulation results show that this strategy not only smooth the PV fluctuations, but also creates profits from peak shaving.