Abstract： To decrease the welding costs, an innovation was proposed to realize a stable consumable doubleelectrode gas metal arc welding process with single power supply. Based on the xPC target system with realtime target environment，welding experiments were conducted. The results show that a stable welding process was realized; the stable welding parameter of bypass wire feed speed were also acquired when the main welding current was 300,350,400,450,500 or 550A.