Abstract: A hybrid generator set comprises an engine/generator or another controllable electrical source which provides a variable voltage electrical output, this output is rectified and fed to a DC to DC converter, the output (VDC) of which is monitored by a control circuit. This output serves as an intermediate DC output, which typically is used to power an inverter to generate an AC output which supplies an external load. The use of the DC to DC converter isolates the intermediate DC output from the generator output, and allows the generator set to operate efficiently over a wide engine/generator speed range, according to load demand.