The Importance of Solar Inverter in Solar Energy System

As a conversion equipment of solar power, the function of solar inverters plays a key role in the whole power station. The solar inverter is the core component of solar power system, which can convert the DC electricity produced by solar components into a sine waveform current, and connect it to the load or incorporate it into the power grid. The main function is to convert the DC electricity of the solar panel to the AC electricity for home using. However, the solar inverter not only has the function of DC electricity and AC electricity conversion, but also has the active operation and shutdown functions, the MPPT function, the inspection and control function of islanding effect.

1. The active operation and shutdown function of solar power inverters

After the sun rises in the early morning, the amount of solar radiation has gradually increased, and the output of solar panels is also accompanied by increasing. When the power required by the solar inverter is reached, the solar electric inverter starts to operate actively. After entering the operation, the solar inverter will be in charge of the output power of the battery board components at all times. As long as the power of the solar panel component is greater than the power required by the inverter target, the inverter continues to run; and it won't stop until it is at sunset, the inverter can run even on rainy days. When the output of the solar panel component becomes smaller and the output of the inverter is close to zero, the inverter will automatically enter the standby.

2. The MPPT function of solar inverters

When the light intensity and temperature change, the input power of solar components shows linear variation. The solar module is not a constant voltage source, nor is it a constant current source. The power of solar inverter will change with the output voltage, which is not directly related to the load. Its output current starts as a horizontal line, and will rise with the increase in voltage, when a certain power is reached, it will decrease while the voltage increasing, and when the component open circuit voltage is reached, the current will decrease to zero.

3. The inspection and control function of solar electric inverters' islanding effect

In the case of normal power generation, the photovoltaic grid-connected power generation system is connected to the power grid and transports effective power to the grid. However, when the power grid is out of power, the photovoltaic grid-connected power generation system may still be working, and the local load is in an independent operation state, this situation is called islanding effect. When the islanding effect of the solar power inverter occurs, it will cause great hidden dangers to life safety, power grid operation and solar inverter itself. Therefore, the inverter needs to meet the standard specifications of the network access, and the photovoltaic grid-connected inverter must have the inspection and control function of islanding effect.