Intelligent Control Of Starting Arcing Process In GMAW

Because of energy saving, low cost and easy automation of CO₂welding, it iswidely used in the welding area of low-alloy steel and low-carbon steel structure. AsCO₂welding developping in automation and intelligent field, the efficiency of CO₂welding is getting higher. In order to obtain higher efficiency of welding arc starting,the Success rate of arc ignition is more important.To improve the success rate ofstarting CO₂welding, and reduce the blasting off in the starting arc phase and suchproblems, this paper puts forward the welding arc starting stage for high-power arcstarting, small power dimension, and welding arc arc starting stage provide slow wirespeed control scheme.The test weld power chooses dsPIC30F6010as the control core by which it canoutput six PWM signals.Four of them are used to control the IGBT driving,anotherone control the wire feed speed.The system adopted the neuron PID controller forclosed loop control, constant power control in the starting arcing stage, constantcurrent control in the short circuit stage, and constant voltage control in the arcburning stage.The system has adopted MATLAB software to simulate the controller,and compared the neuron PID controller with the traditional PID controller. Thesimulation result shows that the neuron PID controller performance is better. In thepaper,the relevant hardwares of the system are introduced in details, including wirecontrol circuit, IGBT drive circuit and protection circuit; and what is more it hasdesigned starting arcing program, short circuit control program, arc burning controlprogram, interrupt program and so forth.With Hanover welding quality analyzer and High-speed photographic apparatus,welding electrical signals and dynamic process of welding are analyzed,and the wirefeed speed on the success rate of the starting arc stage is researched.Then comparativeanalysis are used in the starting arc phase of constant power control and constantcurrent control on arc properties,compared with the domestic welding.The resultsshow that the slow wire feeding combined with the constant power control methodhas a good starting arc performance.