| 摘要 |
<p>According to the present invention, an indentation detection control error is prevented in a case where a plurality of welding power sources are used at the same time. The plurality of welding power sources generate arcs for welding in common works and at least two of the welding power sources detect a volume indentation Nd, which is a precursor of arc re-generation from a short-circuit state, by using a welding voltage detection signal Vd1. When the indentation is detected, a welding current Iw1 is reduced for arc re-generation. The welding voltage detection signal Vd1 includes a voltage value that is generated by an inductance value of a common energization path where a combined welding current Ig is energized. When a decrease in the resistance value of the volume is determined St in the short-circuit state, the detection Nd of the indentation is prohibited. Accordingly, an indentation detection error can be prevented without notifying welding current drop timing between the welding power sources.</p> |
