Independent photovoltaic power generation system
The independent photovoltaic power generation system consists of a solar photovoltaic array, a battery pack, a charging controller, a power electronic converter (inverter), and a load. The working principle is that the solar radiation energy is first converted into electricity through the photovoltaic array, and then converted by the power electronic converter to supply power to the load. At the same time, the excess electric energy is stored in the energy storage device in the form of chemical energy after passing through the charging controller. In this way, when the sunshine is insufficient, the energy stored in the battery can be converted into AC 220V and 50 Hz electrical energy for AC load after power electronic inverter, filter and power frequency transformer boost. Solar power generation is characterized by daytime power generation, and the load is often all-weather electricity, so the energy storage components in the independent photovoltaic power generation system are essential, and the energy storage components used in the project are mainly batteries.
Grid-connected photovoltaic power generation system
Grid-connected photovoltaic power generation system consists of photovoltaic array, high-frequency DC/DC booster circuit, power electronic converter (inverter) and system monitoring part. The working principle is that the solar radiation energy is converted by the photovoltaic array, and then transformed into high-voltage direct current after high-frequency DC conversion, and then output sinusoidal AC current consistent with the grid voltage frequency after the power electronic inverter inverter.
The difference between the above two photovoltaic power generation systems is that the grid-connected photovoltaic power generation system is directly connected to the grid, so the power surplus of the photovoltaic array and the parallel grid can be complementary, eliminating the necessary energy storage components such as batteries in the independent photovoltaic power generation system, not only reduces the cost of the system, but also improves the stability of the system. At the same time, the solar radiation intensity in summer is large, and the photovoltaic system generates more power, which can play a regulating role in the peak load of the summer power grid. With the large-scale application of solar photovoltaic power generation in recent years and the rapid decline in the price of solar modules, grid-connected systems will undoubtedly be more widely used.
The above content is from Wikipedia.
