钨极氩弧焊弧长自动控制系统

针对钨极氩弧焊因工件表面高低不平、钨极烧损以及焊接变形等导致电弧弧长波动的问题,基于单片机和步进电机细分驱动技术,以电弧电压作为弧长表征量,设计了滤波电路解决焊前高频引弧及焊时稳弧干扰问题,设计与制作了弧长自动控制系统,编写带死区变积分PID控制算法和控制程序。焊接试验表明:高频高压干扰能完全被滤除,系统稳定性好;变积分PID控制算法应用于TIG焊接弧长自动控制可显著提高系统的响应速度和控制精度,具有更好的应用前景。

System of arc length automatic control of TIG welding

For the problem of arc length fluctuation due to the uneven surface of the workpiece,the tungsten burning loss and welding deformation,based on the single chip and stepper motor subdivision drive technology,taking the arc voltage as the arc length representation quantity,a filter circuit is designed to solve the problem of high-frequency interference during arc initiation and stabilization;a arc length automatic control system is designed and manufactured,and the PID control algorithm and control program are given.Welding test shows:High-frequency high-voltage interference can be completely filtered and the system stability is good;Variable integral PID control algorithm applied to TIG welding arc length automatic control can significantly improve the system response speed and control accuracy,this system has a better application prospect.