Design of Controlled Short-circuit Transifer GMAW Power Supply Based on Post-Chopper Circuit

When gas metal arc welding (GMAW) is used and in short-circuit transfer, the weld seam is well formed and the transfer frequency is high. However, when the arc is reignited, the arc force generated by the large current will cause the splash of the transfer metal, which causes a large amount of splash in the short-circuit transfer. The controllable short-circuit transfer technology can significantly reduce the amount of spatter by rapidly reducing the welding current when the arc is reignited. Based on the decoupling analysis of arcing and short-circuiting process in the short-circuit process, a controllable short-circuit transfer GMAW power supply based on the subsequent chopper control was designed. The moment of arcing is predicted by detect the welding voltage, and the welding current is reduced at the instant of the combustion arc to reduce the splash. Under the same test conditions, the splash using the traditional short circuit control was large, while the splash using the post-chopper control was significantly reduced.