Gas metal arc welding (GMAW) is a globally commercialized welding process that has been delivering constant voltage output over a range of welding currents with high superior weld finish.

The process occurs when an electrical arc is established and maintained between a base material and a continuously feed wire electrode, along with shielding gas that is flowed continuously around both the wire filler metal and the weld pool.

This process when performed with proper setting of voltage, wire feed rate and other welding parameters delivers excellent weld quality for the desired job. Hence, a stable and consistent arc is necessary to be achieved for uniform welding bead shape throughout the arc on time.

In order to achieve excellent quality performance from welding power source with an approach to improve the stability performance and dynamic response, digital control technique consisting of PID controller is used for speed regulation of wire feed rate and to maintain constant voltage characteristics is proposed.

Over the years, control methods have more advantages in processing large number of data signals through Digital Signal Controllers which executes high-speed instructions for processing the I/O signals within few microseconds to establish a stable and uniform arc.

The experimental results of the prototype show that the proposed digital control method is applicable for all output current ranges

Credits: This abstract / article is contributed by Saurabh Waykole and Sachin Newase of Ador Welding Ltd.