The classification of solar photovoltaic systems:
Solar PV systems (roof solar PV systems, ground solar PV systems and floating solar PV systems
) are mainly divided into the off-grid photovoltaic system and the grid-connected photovoltaic system.
1. The off-grid photovoltaic power generation system is mainly composed of solar cell modules, controllers and batteries. If you want to supply power for AC load, you also need to configure AC inverters.
2. The grid-connected photovoltaic power generation system is the direct current generated by solar modules through the grid-connected inverter. It is converted to meet the requirements of the AC power grid, which is directly connected to the public grid.
The working principle of solar photovoltaic systems:
During the day, the solar cell module generates a certain electromotive force under the light condition, which forms the solar cell array through the series and parallel connection of the modules, so that the array voltage can meet the requirements of the system input voltage. Then, charge the battery through the charge and discharge controllers, and store the electric energy from the light energy conversion.
At night, the battery provides input power for the inverter. The inverter converts direct current into alternating current and sends it to the power distribution cabinet. The power supply is provided by the switching function of the power distribution cabinet. The discharge of the battery is controlled by the controller to ensure the normal operation of the battery. Photovoltaic power station systems should also be limited with protection and lightning protection devices to protect system equipment from over-load operation and lightning strike. The system also maintains the safe use of system equipment.
The composition of solar photovoltaic systems:
1. Solar panels
The solar panel is the core part of the solar photovoltaic system. The role of solar panel is to convert the sun's light energy into electric energy, output direct current into storage battery. The solar panel is one of the most important components in the solar photovoltaic system. Its conversion rate and service life are important factors to determine whether the solar cell has use value.
The solar controller is composed of a special processor CPU, electronic components, the display, the switching power tube and so on.
Batteries are used to store the electricity generated by solar panels during periods of light and release it when needed.
The direct output of solar energy is generally 12VDC, 24VDC and 48VDC. In order to provide electricity to 220V AC appliances, it is necessary to convert the direct current energy emitted by the solar photovoltaic system into AC energy. Therefore, it is necessary to use a DC-AC inverter.