Grid-connected photovoltaic storage VSG system

With the introduction of the “dual-carbon” goal, the importance of the “renewable energy + energy storage” model has become increasingly prominent. The combination of renewable energy and energy storage technology can effectively cope with the volatility and intermittency of wind and solar power generation, and improve the stability and reliability of the power system. In this study, a hybrid photovoltaic-battery-supercapacitor energy storage microgrid system is proposed to improve system operation efficiency and renewable energy utilization. Although the traditional control strategy can handle the tracking of voltage, power and other information, it cannot equip the system with inertial parameters, which leads to difficulties in large-scale grid integration of new energy sources. This problem is solved by the emergence of the virtual synchronous generator (VSG) method, which not only inherits the advantages of the traditional control strategy, but also equips the system with electrical characteristics similar to those of a traditional generator, which reduces the impact of the power generation instability of PV systems on the grid-connected power quality. The effectiveness of the proposed hybrid energy storage system and VSG control strategy is verified through simulation experiments, and the results show that the system can significantly improve the dynamic response capability and stability of the microgrid, which provides technical support for the efficient utilization of renewable energy and reliable grid connection.