Solar inverter is a device that can convert direct current in a solar battery to alternating current. Inverter, also known as power regulator and power regulator, is an indispensable part of photovoltaic power generation system. The working circuit of the solar inverter must be a full-bridge circuit. Through a series of filtering and modulation in the full-bridge circuit, the load and electrical properties of the current are changed to achieve the intended purpose of the user.

A common solar power generation system is mainly composed of four parts, namely solar panels, charge controllers, solar inverters and batteries. The solar panel is a device that provides direct current, which can convert solar energy into electrical energy; the charge controller is mainly responsible for controlling the conversion of energy; the solar inverter converts the direct current of the panel into alternating current for storage of the battery. The alternating current is stored for use by people. The solar inverter plays a linking role in the whole solar power generation system.

Features of Solar Inverters

The main features of solar inverters are centralized inverter and string inverter. The scale of the solar power generation system is generally very large. If a solar panel corresponds to an inverter, it will cause a waste of resources, which is very impractical. Therefore, in actual production, the solar inverter is a centralized inversion of the direct current generated by all the panels and converts it into alternating current. Therefore, the scale of the solar inverter is generally adapted to the scale of the panel. Therefore, a single solar inverter obviously cannot meet this requirement, which leads to another feature of the solar inverter, which is often used in strings. .

The function of solar inverter

The inverter not only has the function of DC-AC conversion, but also has the function of maximizing the performance of the solar cell and the function of system failure protection. In summary, there are automatic operation and shutdown function, maximum power tracking control function, anti-independent operation function (for grid-connected system), automatic voltage adjustment function (for grid-connected system), DC detection function (for grid-connected system), DC grounding detection Function (for grid-connected system). Here is a brief introduction to the automatic operation and shutdown functions and the maximum power tracking control function.

1. Automatic operation and shutdown function: After sunrise in the morning, the solar radiation intensity gradually increases, and the output of the solar cell also increases. When the output power required by the inverter task is reached, the inverter starts to operate automatically. After entering the operation, the inverter will take care of the output of the solar cell module all the time. As long as the output power of the solar cell module is greater than the output power required by the inverter task, the inverter will continue to operate; The inverter can also run on rainy days. When the output of the solar cell module becomes smaller and the output of the inverter is close to 0, the inverter forms a standby state.

2. Maximum power tracking control function: The output of the solar cell module changes with the solar radiation intensity and the temperature of the solar cell module itself (chip temperature). In addition, because the solar cell module has the characteristic that the voltage decreases with the increase of the current, there is an optimal task point where the maximum power can be obtained. The intensity of solar radiation is changing, as is the apparent optimal mission point. Regarding these changes, the task point of the solar cell module is always at the maximum power point, and the system has always obtained the maximum power output from the solar cell module. This control is the maximum power tracking control. The biggest feature of inverters for solar power systems is that they include the function of maximum power point tracking (MPPT).