A portable power supply includes an engine-driven generator that generates a
first
AC power. A rectifier rectifies the first AC power to a first DC power. A DC/DC
converter converts a second DC power from a storage unit to a third DC power. A
controller selectively enables one or both of the rectifier and the DC/DC converter
to provide one or both of the first DC power and the third DC power to the input
of an inverter. The inverter converts the DC power at its input to a second AC
power. Alternatively, the power supply advantageously includes a second generator
and a second rectifier. The outputs of the two rectifiers are summed and the sum
of the two outputs is provided as an input the inverter to extend the range over
which a constant second AC power can be provided.