Process for operating a current source comprises transferring energy from a secondary cycle via a return unit into a direct voltage intermediate cycle in a low load phase for maintaining a welding electric arc

摘要

Process for operating a current source comprises transferring energy from a secondary cycle via a return unit into a direct voltage intermediate cycle in a low load phase for maintaining a welding electric arc and regulating a current with a load-dependent switching frequency of switching elements (3, 4, 40, 41), regulating to a symmetrical magnetization of an output transformer (15). Also comprises adjusting the switching frequency of the switching elements to a multiple of the network frequency so that the switching elements are resonantly controlled. An Independent claim is also included for a current source with a resonance cycle.