Investigation on Microprocessor Based Transient Waveform Control of Short Circuit Transfer Mode CO_2 Welding

摘要

In this paper, the process of short circuit transfer mode CO_2 welding has been analyzed. A new kind of simple and flexible CO_2 welding system was developed to carry out waveform control, and the principle of this system was introduced. The system was consisted of IGBT inverter, PWM circuit and Microprocessor unit (MPU), in which the output current of constant current (CC) power supply could be changed according to physical process, welding parameters could be adjusted coordinately to realize the one-knob control, and the variable down slope rate control could be used to ensure a stable welding process. By applying this transient waveform control welding spatters have been greatly reduced and weld bead formation improved. The welding experiment results proved the effectiveness of this control approach.