Illinois Tool Works Inc.
Variable speed engine driven generator for providing welding and auxiliary power

Abstract:

A method and apparatus for providing welding-type power derives motive power from a variable speed engine and driving a variable frequency generator with the motive power to provide a generator output. The generator output is preregulated to provide an intermediate signal, and the preregulating is controlled at least in response to feedback indicative of the welding-type output power. Welding-type output power is derived from the bus, and controlled at least in response to the welding feedback. Auxiliary output power is also derived from the bus, and controlled at least in response to feedback indicative of the auxiliary output power. The speed of the engine is controlled at least in response to one of the auxiliary feedback and the welding feedback. Energy produced by the engine that is not used as an output is stored by batteries. When the output exceeds the energy generated, the difference is supplied by the batteries.