摘要
Arc length stability and droplet transition consistency are key factors for the pulse metal inert gas （MIG） welding quality. A new control strategy is proposed based on pulse current waveform adjustment to stabilize the welding process. After sufficient analysis of the droplet transition process, key current waveform parameters are refined that can affect the welding quality greatly. In order to achieve the optimal nonlinear control of parameters, the fuzzy controller is designed successfully with two inputs and three outputs in field programmable gate array （ FPGA ）, which occupies fewer resources than PID controller and has higher control performance. Experimental results show that the arc length can be adjusted fast in full range of welding current, the welding process is stable, the droplet transition has good consistency, and the welding quality is perfect.
Arc length stability and droplet transition consistency are key factors for the pulse metal inert gas （MIG） welding quality. A new control strategy is proposed based on pulse current waveform adjustment to stabilize the welding process. After sufficient analysis of the droplet transition process, key current waveform parameters are refined that can affect the welding quality greatly. In order to achieve the optimal nonlinear control of parameters, the fuzzy controller is designed successfully with two inputs and three outputs in field programmable gate array （ FPGA ）, which occupies fewer resources than PID controller and has higher control performance. Experimental results show that the arc length can be adjusted fast in full range of welding current, the welding process is stable, the droplet transition has good consistency, and the welding quality is perfect.
基金
This research is supported by the National Natural Science Foundation of China （ No. 51207083 ） , Jinan Youth Science and Technology Star Plan （No. 20110304） and Independent Innovation Foundation of Shandong University （No. 2010GN067 ）.
