The solar inverter is a critical component of your solar power system. The solar panels produce direct current (DC), which needs to be converted into alternating current (AC) before it can power your home. Solar inverters take all the DC power generated by the solar panels and inverts it to AC electricity that can be used to power anything you have that needs electricity.
However, the solar inverter is not only a DC-AC conversion function, but also has an active operation and deactivation function, a maximum power tracking MPPT function, and an islanding effect inspection and control function.
Active operation and deactivation function
After the sun rises in the morning, the amount of solar radiation gradually increases, and the output of the solar panel also increases. When the output power required by the inverter is reached, the inverter will start active operation and constantly monitor the output power of the solar panel assembly.As long as the output power of the solar panel assembly is greater than what the inverter requires, the inverter will continue to run until sunset. When the output of the solar panel assembly becomes smaller and the output of the inverter approaches zero, the inverter will automatically enter the standby state.
Maximum power tracking MPPT function
When the sunlight intensity and temperature change, the input power of the solar module changes linearly. The solar module is neither a constant voltage nor a constant current sources. Its power varies with the output voltage and has no direct relationship with the load.Its output current is a horizontal line initially as the voltage increases. When it reaches a certain power, it decreases as the voltage increases. When it reaches the open circuit voltage, the current decreases to zero.
Islanding effect detection and control function
The photovoltaic grid-connected power generation system is connected to the international grid and delivers effective power to the international grid. However, when the international grid is out of power,the photovoltaic grid-connected power generation system may still continue to work and operate independently with the local load. This situation is called the islanding effect. When the islanding effect occurs in the inverter, it will cause great harm to personal safety, grid operation and the inverter itself. Therefore, the photovoltaic grid-connected inverter must have the islanding effect detection and control function.
