CO2气体保护焊短路过渡过程的闭环实时控制

为了减少CO2气体保护短路过渡焊的飞溅，本文提出了短路过渡过程的闭环实时控制思想并进行了试验研究。在熔滴与熔池发生短路及液体小桥爆断这两个最容产生飞溅的时刻，利用大功率电子关元件切换焊接回路外串电阻的方法及时降低焊接回路中的电流。在前一时刻维持较低电流至溶滴与熔池充分接触，在后一时刻维持较低电流至熔滴过渡完毕，该方法能有效地抑制由瞬时短路造成的大颗粒飞溅和由电爆炸产生的细颗粒飞溅，实现了CO2气体保护焊短路过渡过程的闭环实时控制。

The Closed-loop Real-time Controlling of Short-circuiting Transfer in CO2 Arc Welding

In this paper, an idea of closed loop real time controlling of short circuiting transfer is proposed and is experimentally studied for decreasing the spatter in the short circuiting transfer process of the CO 2 welding. At the two moments when spatter is most easily produced short circuiting between droplet and welding puddle and the liquid bridge exploding welding current is reduced in time by the method of high power element switching the resistance which is in settes connection with the welding circuit. At the former moment, a low current is held until the droplet fully contacts with the welding pool. At the later moment, another low current is held until the droplet transfer ends, and the large spatter caused by the incipient short circuiting and the small spatter caused by electrical explosion can be obviously reduced. The closed loop real time control of short circuiting transfer process of CO 2 welding is realized.