Multiphase rotary AC generator and rectifier for welding - where generator windings are connected together to reduce upper harmonics in generator output

摘要

The generator possesses several switchable partial windings, which are connected in parallel and which feed a rectifier supplying current e.g. for arc welding. When only some (a) of the windings are connected to the rectifier, the remaining windings (b), with the ends of the phases possessing equal vectors of no-load voltage, are connected together. In the invention, when only some windings (a) are connected, i.e. for a low welding current when conditions in the generator are most critical, the upper harmonics are reduced by 30% as compared with those obtd. conventionally and the quality of the welded seam is improved.