Jul 02, 2024
The difference between DC coupling and AC coupling
Energy storage technology refers to the process of storing energy through media or equipment and releasing it when needed; photovoltaic + energy storage combines solar photovoltaic power generation with energy storage technology to store the electric energy generated by the photovoltaic system so that it can be used when needed. Ensure stable power supply when needed. Currently, the system solutions for photovoltaic + energy storage on the market mainly include DC coupling and AC coupling. So what is the difference between these two solutions? The difference between DC coupling and AC coupling DC coupling means that energy storage cells and photovoltaic modules are connected to the DC side of the integrated photovoltaic and storage machine. The integrated photovoltaic and storage machine is directly connected to the photovoltaic modules, and the energy collection point is on the DC side. AC coupling means that the energy storage system and the photovoltaic system are connected on the AC side. , the energy storage system (battery, energy storage inverter) and the photovoltaic system (photovoltaic modules, photovoltaic inverter) work independently of each other, and the energy collection point is on the AC side. However, due to differences in circuit structures and electrical equipment between the two, there are also major differences in working principles, flexibility, efficiency, etc. 1. Differences in working principles DC coupling: In this solution, the photovoltaic inverter and the bidirectional converter are integrated into a photovoltaic and storage integrated machine, and are directly connected to the photovoltaic modules, power grid, battery, etc. to form a whole. When the photovoltaic system is running, the electricity generated can charge the battery through the photovoltaic storage integrated machine, supply power to the load, or be input into the power grid. AC coupling: This solution includes two parts: photovoltaic system and energy storage system. The photovoltaic system consists of photovoltaic arrays and photovoltaic inverters; the energy storage system consists of energy storage inverters and batteries. The two systems can operate independently without interfering with each other, or they can be separated from the power grid to form a micro-grid system. When the photovoltaic system is running, the generated power can be used to power the load through the photovoltaic inverter or be input into the grid, or it can be used to charge the battery through the energy storage inverter. 2. Flexibility Differences DC coupling: In this solution, photovoltaic modules, photovoltaic storage integrated machines and batteries are in a serial state and are closely connected to each other. The addition and removal of equipment is complicated and the flexibility is average. It is mainly used in new photovoltaic markets, such as newly installed Photovoltaic storage systems, photovoltaic modules, integrated photovoltaic storage machines and batteries...
اقرأ أكثر