电阻点焊机精密电流控制方法研究  

Method Study of Precision Current Control of Resistance Spot-Welder

作　　者：王道顺[1] 柳光伟 王子博 WANG Daoshun;LIU Guangwei;WANG Zibo(School of Mechanical Enginering,Dalian Jiaotong University,Dalian 116028,China;School of Engineering and Science,Louisiana Teeh University,Ruston LA71270,USA)

机构地区：[1]大连交通大学机械工程学院,辽宁大连116028 [2]路易斯安那理工大学工程与科学学院,美国la71270

出　　处：《大连交通大学学报》2018年第5期84-88,共5页Journal of Dalian Jiaotong University

摘　　要：针对普通电阻点焊机控制节拍时间长、焊接时动态电阻引起的焊接电流无法及时调节的问题,提出一种在常规控制基础上增加前馈控制的方法.该方法通过分析研究焊接材料在焊接过程中动态电阻变化规律,将提前得到的动态电流数据引入到下一节拍的导通角计算中,提前对导通角进行修正,从而能得到更加准确的焊接电流.针对普通点焊机的特性,设计了独特的控制算法,具有比常规控制算法更好的效果.探讨了焊接电流反馈环节的A/D转换速度要求及计算精度,给出了普通微处理器如何保证反馈电流计算精度的有效方法.最后,提出了利用反馈信息实时修正动态电流数据的更加有效的解决方案.According to the problem of lengthy control time and the lagging adjusting of welding current caused by dynamic resistance of the general resistance spot welder,a new method of feedforward control based on conventional control is presented. By introducing the dynamic current data into the calculation of the conduction angle in the next beat,this method is used to analyze the law of dynamic resistance in welding process in advance of modifying the conduction angle,so more accurate welding current can be obtained. Aiming at the common characteristics of the spot-welder,a unique better control algorithm than the effect of the conventional control algorithm is designed. The A/D conversion speed requirements and calculation precision of welding current feedback are discussed,and an effective method to ensure the accuracy of feedback current is given.At last,a more effective solution is proposed to modify the dynamic current data making use of feedback information in real time.

关 键 词：动态电阻 前馈控制 焊接电流 

分 类 号：TG453.9[金属学及工艺—焊接]