Modeling and Control of a Full-Bridge DC-DC Converter for Arc Welding Applications

This study presents the modeling and control of a full-bridge DC-DC converter applied to Gas Metal Arc Welding (GMAW) in short-circuit transfer mode. GMAW is widely used in industrial manufacturing due to its versatility. However, achieving stable operation in short-circuit transfer requires precise regulation of the welding current and arc voltage. To address this challenge, a simplified yet representative model of the converter and load dynamics is developed. Based on this model, a dual-loop digital control strategy is implemented to ensure fast transient response, reference tracking, and improved stability of the welding process. The effectiveness of the proposed approach is experimentally validated on an industrial-grade prototype, demonstrating agreement between theoretical predictions and measured waveforms.