Hybrid Energy Storage Control Strategy Based on Energy Prediction for Photovoltaic Microgrid

Due to the strong randomness of photovoltaic power and load power, the grid-connected power of photovoltaic microgrid fluctuates greatly. The control strategy of energy storage system(ESS) designed from a short time scale is difficult to meet the control requirements of microgrid in a long time scale. In order to solve this problem, this paper puts forward a hybrid energy storage system(HESS) control strategy based on energy predictive, low pass filtering method is used for the distribution of the HESS power output. According to the predictive value of photovoltaic power and load power, grid connected power planed value, estimate the system energy difference in a control cycle, and revise energy storage output power based on the system energy difference. On the basis of the energy storage power output, coupled with power difference, state of charge(SOC) and other boundary conditions to control HESS. The simulation model was built on the MATLAB/Simulink platform, and the simulation results show that the energy storage battery can maintain reasonable SOC on a long time scale in both sunny and cloudy weather, and the grid-connected power of the microgrid can track the power scheduling curve, which proves the effectiveness of the control strategy proposed.