焊接电弧的微机模糊控制设计与应用

提出用模糊控制取代ＰＩＤ控制。工艺试验表明，所设计的通用模糊控制器完全可以取代ＰＩＤ控制器，其具有较好的动态特性和令人满意的稳态特性，还具有比ＰＩＤ控制更好的工作可靠性和稳定性。

Application of Fuzzy Control to the Improvement of Weld Quality

We apply the rapidly emerging fuzzy control technology to improve the quality of welds in China. We now report on how to keep feeding of welding wire nearly uniform under abruptly changing conditions so as to avoid appearance of too big change in arc voltage; such big change usually causes poor quality of weld.Our research is a part of one of the very few projects concerning fuzzy control supported by SFAC (Science Fund of Aeronautics of China).Fig. 3 gives results of laboratory tests. Fig. 3 (a) shows the variations of arc voltage (upper curve) and feeding of welding wire (lower curve) under fuzzy control. Fig. 3(b) gives similar results under PID control. It can be seen that there is some reduction in non- uniformity of arc voltage under fuzzy control as compared with PID control; a more nearly uniform arc voltage is of course good for quality of weld. More important still is that, when the distance of welding gun from work piece changes by 5mm, which is somewhat higher than what happens under real- life conditions, PID control can not keep arc working continously, but fuzzy control does allow arc working more or less normally.