Abstract: By analyzing the dynamic characteristics of welding arcs and the characteristics of IGBT‚an electronic analog load of welding arcs was designed and a new experimental method for the dynamic characteristic test of arc welding power source was proposed．In this method‚the dynamic characteristic variation of the welding arc in actual welding process is simulated by using IGBT as the rheostat and is evaluated by the dynamic electronic parameters of arc welding power sources．Technique research on the designed electronic analog load was then carried out．Experimental results indicate that IGBT can be used as the electronic analog load to simulate the dynamic current and voltage variation of welding arcs．

Key words: welding arc, electronic analog load, dynamic characteristic, IGBT