Gentlemen,
I believe in a paralleled generator situation like Adrian is talking about, he is correct.
When synchronizing generators to the grid, you increase the speed control to take on more real load. The actual generator speed does not change because it is locked to the grid frequency due to the circulating currents, however it will pick up more of the real power load.
To increase the paralled generator's reactive loading, you try to increase the generator's output terminal voltage.
I believe the grid tie inverters are designed to try to vary their output frequency to control how much real power they output. Obviously a KW sized unit will not pull the utility units off frequency, but they will try to unload them.
