Research On Control Technology Of Photovoltaic And Energy Storage Integrated System

In today's world,environmental pollution and energy shortage are exacerbated.Vigorously developing the new energy power generation industry is an effective measure to solve these problems.However the photovoltaic power generation system is uncontrollable due to the characteristics of solar energy,especially for independent photovoltaic power generation system,the system has to stop in the absence of sunlight.These problems seriously hampered the development of photovoltaic power generation industry.Energy storage technology is a good solution to the problem of power generation volatility in photovoltaic systems so far.When the sunlight is abundant,excess energy is stored.When the sunlight is not sufficient,the energy released by the energy storage system is supplemented to smooth the fluctuation and stabilization of the photovoltaic System output,greatly improving the reliability of photovoltaic power generation system.The research on control technology of photovoltaic and energy storage integrated system is carried out under this background.In this paper,firstly the topology structure of the integrated photovoltaic and energy storage system was designed,with a single photovoltaic cell and battery unit being connected together through the main circuit.At the same time,the capacitance and inductance parameters of the main circuit were designed.Then the reasonable control strategies were proposed for the integrated system,including the maximum power point tracking(MPPT)algorithm of photovoltaic cells and the state of capacity(SOC)of battery detection algorithm.Finally,based on the analysis of the energy flow model of the system,the output control strategy of the whole system is designed to realize the system energy optimization.When a single photovoltaic and energy storage integrated system can not meet the required load energy,multiple system cascaded operation mode is adopted.The output power of the photovoltaic cell may also be inconsistent when the environment of the photovoltaic cell is different.In order to ensure efficient and smooth operation of the system,a load sharing strategy based on double bus control is designed for the cascaded optical storage system to ensure that the output of each optical storage system is consistent and the service life of the battery is prolonged.In order to verify the feasibility of the proposed design scheme of the photovoltaic and energy storage integrated system,the control strategies mentioned above were simulated and analyzed through the MATLAB/Simulink simulation.Based on the simulation analysis,the experimental prototype with the capacity of 20 W was designed.The control circuit based on TMS320F28335 chip is designed,and the corresponding control program is written at the same time.Finally,the experimental verification of control strategies for the integrated system was carried out.The experimental and simulation results have proved the feasibility of the proposed scheme.