Illinois Tool Works Inc.
Method and Apparatus For Providing Welding Type Power Using Double Forward Converter

Abstract:

A method and apparatus for providing welding type power includes receiving input power and pulse width modulating a first forward converter and a second forward converter so that they operate as a pulse width modulated double forward converter to provide a welding type output. A phase relationship between the first forward converter and a second forward converter is selected from at least two available phase relationships using a controller. The controller includes a pwm module, and the pwm module includes a phase relationship module. The at least two available phase relationships are at least two of variable phase shifting, fixed phase staggering and locked in phase. The selected phase relationship is maintained over a predetermined range of outputs.