Computer Simulation Of Wave Control On Inversion Power Source-Arc System In CO₂ Short-Circuit Welding

CO₂ arc welding has been widely applied because of its advantages. But the large spatter and bad bead shape are two remarkable shortcomings of short-circuit transfer and limit its more development. This study has taken the measure of waveform control to solve the problems. The waveform control needs good arc welding power source with high dynamic characteristic, while inversion power source may satisfy the former request because of excellent dynamic characteristic. However, such procedures as more transient transfer and the non-linearity of process must be faced to under waveform control and many practical experiments should be expected. The practical experiments may be predigest and the cycle of experiments is shortened .After the CO₂ short-circuit transfer process has been studied in this dissertation, and according to the character of the non-linearity of short-circuiting transfer in CO₂ gas shielded arc welding, the simulation model of the system of inversion power-arc is founded and analyzed by use of the MATLAB simulation software on the base of the thinking of waveform control. In the simulation model of waveform control, the feedback of current and voltage is taken at the different time. The duty ratio is changed by the PWM control model in inverter power source to change the output of power source.The simulation operation about the dynamic process of CO₂ short-circuiting transfer welding is implemented on the founded simulation model so that this paper reports the dynamic arc-waveform of short-circuit transfer process in CO₂ arc welding which has embodied the effect of inversion harmonic wave. It has compared with the true waveform. The both are consistent.The MATLAB software may be used as an excellent simulation tool on the short-circuiting transfer process of CO₂ arc welding and be a excellent tool on guiding experiment.