The inverter is the heart of every photovoltaic system. Solar inverter refers to a device from the field of renewable energies that converts the direct voltage from solar modules into alternating voltage, i.e. converts direct current into alternating current. In addition, photovoltaic inverters optimize the operating point of the solar modules in order to achieve the highest possible energy yield.
The inverter should be positioned as close as possible to the feed-in point. The cable losses on the AC side are significantly higher than on the DC side, which is why the cable length to the feed-in point should be as short as possible.
A distinction is made between module and string inverters, which are intended for private and industrial use, and central inverters, which are usually installed in solar parks.
On-Grid and Off-Grid inverters
Inverters connected to the mains automatically adjust their frequency to the mains frequency.
For isolated applications (off-grid battery systems), where a photovoltaic system is not connected to the general power grid, a separate frequency control is absolutely necessary.
Source: Wikipedia, SolarServer, photovoltaik.one