Working Principle of the Sunny Island Inverter

The Sunny Island is a battery inverter that is connected directly to a battery-storage system. The Sunny Island forms the alternating current grid of the off-grid system and at the same time regulates the voltage and frequency in the alternating current grid.

Both electrical loads and energy generators are connected directly to the alternating current grid. Energy generators, e.g. PV inverters, feed into the alternating current grid of the off-grid system and thus supply the electrical loads.

The Sunny Island regulates the balance between the energy fed in and energy used and features a management system that manages the battery, generators and loads. If there is excess energy available (e.g. high solar irradiation and low consumption), the Sunny Island redirects energy from the alternating current grid and uses this to charge the battery. If there is insufficient energy available (low or no solar irradiation and high consumption), the Sunny Island supplies the alternating current grid with energy from the batteries.

The Sunny Island automatically checks the availability of the alternating current grid and system components. Therefore, additional control- and monitoring units are not necessary. This simplifies system operation and reduces capital expenditure.