In order to improve the penetration of distributed photovoltaic generation in distribution network

the issue of power fluctuations needs to be solved. In this paper

a real-time dispatch strategy for centralized energy storage station（CESS） was used to smooth power fluctuations of high penetration photovoltaic generation. A double-layer structure of control strategy was designed

including the real-time dispatch method of CESS in the distribution system and the power allocation method among all the energy storage devices in CESS. The dispatch layer would update the output power of distributed photovoltaic generation and the predictive values of load demand constantly to dispatch the energy storage station real-timely and to accommodate the power balance fluctuations of the distribution system

considering the constraints of charge and discharge power

capacity and cycles. The power allocation layer would proceed real-time optimization allocation following the dispatch instructions with the minimum cost of CESS as its objective

based on the performance parameters and operation parameters of each battery package. And the power allocation layer would fully consider the total rest charge and discharge capacity that could be dispatched in the next period. The simulation results of example cases show that the proposed double-layer dispatch strategy can not only smooth the power fluctuations

reduce the peak-valley difference of injection power from 13 MW to about 5 MW

increase the photovoltaic power accommodation capability

and mitigate the influence of grid connected photovoltaic power station on power grid

but also optimize the operating condition and reduce the total operating costs of CESS

while maintaining the initial and final SOCs of the CESS approximately equal during one day. Thus

the proposed strategy not only meets the cyclic dispatch requirements of the CESS

but also improves the economy of the CESS.