A lightweight engine-driven generator set including a
stator having at least first and second windings (preferably three-phase) and a rotor having a soft
magnetic core and a plurality of
high energy product permanent magnets, separated by consequence poles, disposed
proximate the
stator such that
relative motion of the rotor and
stator causes
magnetic flux from the rotor to interact with and induce current in the stator windings. The first winding includes a predetermined number of turns corresponding to a first predetermined
voltage output; and the second winding includes a predetermined number of turns corresponding to a second predetermined
voltage output, the respective windings being grouped together as a unit and wound about the core such that the respective winding coils are wound in continuous close
thermal contact with each other. The first winding generates a relatively
high voltage, low amperage
signal, and the second winding generates a relatively
low voltage, high amperage
signal; and a switch provides for selection of the desired output. Preferably the rotor is a
hollow cylinder mounted on the engine shaft for rotation about the stator and such that the proper gap distance between rotor and stator is maintained during rotation of the rotor without bearings external to the engine. The
low voltage, high amperage winding (or winding group) may be tapped to provide a selectable
voltage output. Suitable rectifiers and inverters may be provided to effect selective DC and AC output signals.