Intelligent control of arc stability and arc length in aluminum alloy pulsed GMAW

Pulsed gas metal arc welding (GMAW) can improve the heat input and heat distribution in the aluminum (Al) alloy welding process, thereby improving weld quality. However, the arc easily fluctuates during pulsed GMAW, which can seriously affect weld quality. This paper proposes an arc length control algorithm for Al alloy pulsed GMAW. An arc length control method based on proportional-integral-derivative (PID) control with instantaneous arc voltage as the feedback variable and wire feed speed (WFS) as the control variable is introduced. A support vector machine (SVM) model is established to predict the optimal reference arc voltage and a reference arc voltage prediction model is obtained by SVM fitting. Intelligent control of both arc stability and arc length can be realized.