Research of CO2 welding inverter power source under current waveform control

STT (surface tension transition) waveform control method is efficient method to realize no splash transition and improve appearance of welding in CO₂ welding process. This system directly controls welding current, and given value is the STT current waveform of the short circuit, burning arc stage which can meet to realize without splash transition and improve the appearance of welding. It designs the corresponding fuzzy PI controller, constitutes current waveform control system of CO₂ welding inverter power source, and series resistance is added in welding circuit at the end of the short circuit stage to accelerate rate of descending of loop discharge current to reduce the splash and improve the appearance of welding. The simulation results show that the designed controller system can make the welding current rapidly and accurately track the given current waveform, and welding current can meet the conditions of the surface tension transition.