Solar photovoltaic systems are divided into off-grid photovoltaic power generation systems, grid-connected photovoltaic power generation systems and distributed photovoltaic power generation systems:
1. Off-grid photovoltaic power generation system. It is mainly composed of solar battery components, controllers and batteries. To supply power for AC loads, AC inverters must also be configured.
2. The grid-connected photovoltaic power generation system is directly connected to the public power grid after the direct current generated by the solar module is converted into the alternating current that meets the requirements of the mains grid through the grid-connected inverter. Grid-connected power generation systems There are centralized large-scale grid-connected power stations that are generally state-level power stations. The main feature is that the generated power can be directly transmitted to the power grid, and the power supply can be provided to the users through the unified deployment of the power grid. However, this kind of power station has a large investment, a long construction period, and a large area, but it has not yet achieved much development. The decentralized small-scale grid-connected power generation system, especially the photovoltaic building integrated power generation system, is the mainstream of grid-connected power generation because of its advantages of small investment, quick construction, small footprint, and strong policy support.
3. Distributed photovoltaic power generation system, also called decentralized power generation or distributed power supply, refers to the deployment of smaller photovoltaic power generation systems at the user's site or near the site to meet the needs of specific users to support existing distribution networks. The economic operation, or both meet the requirements of both.
The basic equipment of the distributed photovoltaic power generation system includes photovoltaic cell modules, photovoltaic square array supports, DC combiner boxes, DC distribution cabinets, grid-connected inverters, and AC distribution cabinets, as well as power supply system monitoring devices and environmental monitoring. Device. The operating mode is that under the condition of solar radiation, the solar cell module array of the photovoltaic power generation system converts the output energy of the solar energy into the DC distribution cabinet through the DC convergence box and reverses the conversion from the grid-connected inverter to the alternating current supply. The building itself is loaded, excess or insufficient power is regulated by connecting the grid.