subject: What do Solar Inverters Do [print this page] Solar inverters are an integral part of converting to solar energy. Which one you use is dependent on whether you want to be on the grid or off the grid, and there are many safety concerns to take into account.
A solar inverter is specifically a type of electrical inverter. It is used to change the direct current (DC), which is the kind of current collected from solar rays into alternating current (AC), which is used with home appliances and often on a utility grid.
There are three types of solar inverters. Each one is compatible with solar panels, but deciding between them is dependent on whether you want to be on the utility grid or off the utility grid.
1. Stand-alone inverters are used by isolated solar systems where the inverter is used to draw the DC energy from the batteries which are charged by photovoltaic collectors, wind turbines, hydro turbines, and engine generators (they are not used for radiant collectors). Often stand-alone inverters are used in combination with battery charges which help to replenish the battery from the AC source. They do not usually work with the utility grid, which means they do not have to have anti-islanding protection.
2. Grid-tie inverters are specially designed to shut down automatically when the power supply stops working with them. This is for safety reasons, but it also means that they don't work during power outages. Grid-tie inverters match the amount of energy taken from the utility company with solar energy. They also make sure that the solar energy is in phase with the energy from the utility company.
3. The final broad group of inverters is the battery backup inverter. Battery backup inverters take energy from the battery and help to transfer excess energy back to the grid. Battery backup solar inverters can be used during a power outage and also are required to have and use anti-islanding protection.
All solar inverters work with special maximum power point tracking. This helps them work to get the most possible power from photovoltaic solar panels. They also allow for the DC side of the inverter to find the maximum amount of voltage to take in.
Anti-islanding protection is also an important part of solar inverters. Islanding occurs when the utility grid shuts off, or the solar inverter no longer detects the presence of the utility grid. At this time the circuits in the electrical system may happen to resonate at a frequency of the utility grid, fooling the inverter. This is called islanding and is very dangerous. Utility workers may not know that the inverter is still working because the utility grid is off. Anti-islanding protection is often built in and injects small pulses which are out of phase with the AC electrical system which will cancel out stray resonances that may occur when the utility grid is off.
Solar inverters work in correlation with solar panels and other materials. They are integral to solar energy system because they convert the electricity as well as help to provide some safety when using electricity.
