Study on pulsed gas metal arc welding and its digital control strategy

Pulsed gas metal arc welding is an important welding process in advanced manufacturing technology, which makes conventional welding process a finely controllable process. However, this process demands a synergic setting up of pulse parameters in order to retain optimal transfer of droplets which depends on experimental data under various conditions, while the stability of arc length is necessary but difficult to model and has nonlinear and time varying characteristics. In this paper, the process was analyzed in detail, and current control methods were presented and compared. Then, a digital control oriented approach has been suggested, including algorithms of parameters adjustment, PI and fuzzy logic control. An experimental system based on welding inverter and microcontroller was implemented, and the scheme was described here as well.