Four basic requirements that inverters must meet in solar applications

1. Solar inverters are required to have high efficiency. As the price of solar panels is relatively high, in order to maximize the use of solar panels and improve the efficiency of the system, it is necessary to find ways to improve the conversion efficiency of the inverter.

2. Solar inverters are required to have high reliability. At present, photovoltaic power generation systems are mainly used in remote areas, and many power stations are unattended and unmaintained. This requires the inverter to have a reasonable and complete circuit structure, high-quality components, and various protection functions, such as input DC polarity reverse protection, AC output short circuit protection, overheating, overload protection, etc. These are all necessary for the inverter.

3. Solar inverters require a wide range of DC input voltage. The terminal voltage of solar cells varies with load and sunshine intensity, and the voltage of batteries also varies with the remaining battery power and internal resistance. Especially when the battery ages, the terminal voltage has a wider range of variation. For example, the terminal voltage of a 12V battery varies within the range of 10V-16V during use. Therefore, the inverter must ensure normal operation within a larger DC input voltage range and ensure the stability of the AC voltage output.

4. In medium and large-capacity photovoltaic power generation systems, the output of the inverter power supply should be a sine wave with low distortion. The loads of many medium and large-capacity photovoltaic power generation systems are communication or instrumentation equipment, which have high requirements for the quality of the power grid. When medium and large-capacity photovoltaic power generation systems are connected to the grid, in order to avoid causing power pollution to the public power grid, it is required that these solar devices, especially the inverter, output a sine wave current with low distortion.