1. Brief Introduction of Photovoltaic System
① What is a photovoltaic system?
A system that converts solar energy into electrical energy and can power to electrical loads.
② What are the main components?
Solar modules, photovoltaic inverters, battery packs.
③ What is the working principle?
The photovoltaic cells in the solar module convert solar energy into direct current through the photoelectric effect, and then convert the direct current into alternating current through the photovoltaic inverter, and then enter the grid or supply it to the user’s electrical appliances.
2.Photovoltaic system type
① Independent photovoltaic system
Also known as off-grid photovoltaic system, it is usually used in places without power supply, such as fields, warehouses, etc. Since it cannot be connected to the grid, a stand-alone photovoltaic system needs to be equipped with a battery pack to store electrical energy so that it can continue to supply power when there is no sunshine.
② Grid-connected photovoltaic system
It is divided into two types: string type (distributed) and centralized type. After the photovoltaic direct current is converted into alternating current by the inverter, it is directly transmitted to the grid. The advantage of this type of system is that it places extremely low demands on the battery pack, generally cannot or cannot be directly connected to the battery, and generally requires less maintenance.
③ Hybrid energy storage photovoltaic system
This type of photovoltaic system is usually used in places where there is electricity supply, but the electricity supply is unstable. When the power supply of the grid is normal, the photovoltaic system generates power through photovoltaic modules, and the inverter outputs power to supply power to the load. At the same time, the power of multiple lines is stored in the battery pack. When the battery pack is fully charged, the remaining power is transmitted. To the grid, in the absence of light, use the battery and the grid to supply power to the load at the same time. When the grid power supply stops, the hybrid energy storage photovoltaic system is equivalent to a stand-alone photovoltaic system. The power stored in the battery pack is used to supply power to the load, and at the same time disconnect the grid connection, and do not transmit power to the grid.
Because this system has rich functions and can cope with more electricity demand, it costs more and requires more maintenance.
3.How to choose a photovoltaic system
①Determine the purpose and demand, and select the appropriate type of photovoltaic system according to the demand.
②When choosing the size and quantity of solar panels, the installation space and local lighting conditions need to be considered.
③Determine the installation method of the solar panel and design the bracket.
④Select the inverter and determine the inverter type (single-phase, three-phase, input voltage, input current, output voltage, output current, output frequency, battery charging voltage, current, battery discharging voltage, current, grid-connected standard, protection level, etc.)
⑤ When selecting a battery pack, it is necessary to consider the battery capacity, the adaptation of the charging and discharging voltage, current and inverter, and the communication protocol.Adaptation, battery performance and lifespan and other factors.
Post time: Aug-28-2023