Research On Control Strategy For Micro-source Of Photovoltaic And Energy Storage

In recent years, with the rapid development of renewable energy generation technology, the proportion of distributed generation in power system is increasing. As an effective form of full use of distributed generation, micro grid technology plays a very important role in improving the utilization of photovoltaic power generation. Due to the randomness and instability of photovoltaic power generation, it is usually required to cooperate with the energy storage system when it is connected to the micro grid, which can constitute a photovoltaic energy storage system. Energy storage system in the micro grid plays a very important role, mainly because of micro grid power shortfall usually need stored energy balance. Therefore, this paper studies the micro grid system of photovoltaic energy storage system, and puts forward to improve and improve the control strategy of the system, which has good theoretical value and practical significance.Firstly, in this paper, the mathematical model of photovoltaic energy storage power generation system is established, including the mathematical model of the photovoltaic cells, the mathematical model of the photovoltaic array and the equivalent circuit model of the storage battery.Secondly, the control strategy of photovoltaic energy storage system is studied, which includes the control strategy of the DC-DC converter, the DC-AC inverter and the DC-DC converter of the energy storage system. Then, the control strategy of the DC-AC outer loop control strategy is analyzed, and the three control strategies are studied.Thirdly, the control strategy of virtual synchronous generator for photovoltaic energy storage system is proposed. The idea and principle of virtual synchronous generator control are introduced, and the overall control strategy is proposed based on the vector relationship, active power frequency control and reactive power voltage control.Finally, the digital simulation platform of the micro grid system is built by using Matlab/Simulink simulation software, and the control strategy of the PV energy storage system is analyzed. Then, the correctness of the theoretical analysis is verified.