The solar PV system with energy storage on the DC side of the power supply can be installed mainly in DC systems such as photovoltaic power generation, and this design allows the battery combination PV array to be mated and regulated in the DC section of the inverter. The solar PV system and the battery storage system in this system share an inverter, but due to the large difference between the charging and discharging characteristics of the battery and the output characteristics of the PV array, the maximum power tracking system in the grid-connected PV inverter in the original system is specially designed to match the PV output characteristics and cannot meet the output characteristics curve of the storage battery at the same time.
Therefore, such systems need to modify or redesign the inverter of the original system, not only to make the inverter meet the inverter requirements of the PV array, but also to add the charge and discharge controller for the battery bank, and battery energy management and other functions. Generally speaking, the system is a one-way output, that is to say, the solar photovoltaic system in the battery is completely dependent on photovoltaic power charging, the power grid is not able to charge the battery.
The system photovoltaic power array issued by the power in the front of the inverter with the battery for automatic DC balance, the main characteristics of this mode is the high efficiency of the system, the power station power generation output can be dispatched by the internal PV power station, can achieve a seamless connection, the output power quality is good, output fluctuations are very small, etc., can greatly improve the smooth, stable and adjustable performance of photovoltaic power output.
It uses a separate charge/discharge controller and inverter to charge or convert the battery, which is actually an external energy storage device for the existing solar PV system. It can be installed in any kind of PV power station or even wind power station or other power station to form an in-station energy storage system, or it can be built into a completely independent energy storage power station according to the needs of the grid.
This mode overcomes the problem that DC-side energy storage system cannot be dispatched with excess power, its system charging or discharging is completely controlled by intelligent control system or by grid dispatch control, it can not only concentrate the excess power in the whole station to charge the energy storage system quickly and effectively, but even dispatch the cheap low valley excess power from the grid outside the station, which makes the system operation more convenient and effective.
Another model of AC-side access energy storage system is to connect the energy storage system to the grid side. Obviously, these two types of energy storage systems differ only in the access point, the former is to connect the energy storage part to the AC low-voltage side, sharing a transformer with the original PV power station, while the latter is to form an independent energy storage system in the mode of energy storage power station, directly connected to the high-voltage grid.
The AC side access solution is not only applicable to grid energy storage, but also widely used in relatively isolated areas such as islands to form a relatively independent mini-grid power supply system. The AC-side access energy storage system can be implemented not only on new power plants, but also on already built power plants, which can be easily renovated and additionally built, and the circuit structure is clear, and the power generation field and the energy storage field can be built in separate locations with less direct correlation with each other, so it is also easy to operate and control and maintain.
The PV system integration service of Sunrise Energy Co., Ltd. focuses on customer-side energy storage, i.e., the combination of distributed energy storage and customer side. Our technical team takes into account the installation environment, system cost, terminal consumption, etc. to customize the most economical energy storage solution for customers, Our technical team takes into account the installation environment, system cost, terminal consumption, etc. to customize the most economical energy storage solution for customers, which is really deeply customized and reassuring.