Interactions between External Energy Sources and the Stand-Alone Grid

External energy sources have an influence on the power control of the AC sources (e.g. on PV inverters). The Sunny Island regulates the power output of the connected AC sources via the stand-alone grid frequency. The higher the stand-alone grid frequency, the lower the amount of power that is fed into the stand-alone grid from the PV inverters and the wind power inverters ( > Frequency Shift Power Control).

If you start a generator manually, the Sunny Island synchronizes the frequency of the stand-alone grid with the frequency of the generator voltage and connects the stand-alone grid to the generator voltage. This means that the Sunny Island can no longer use the frequency of the stand-alone grid to regulate the AC sources in the stand-alone grid. Power regulation of the AC sources in the stand-alone grid is not possible during synchronization.