Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title A Novel Control Method of Resistance Spot Welding Inverter using Dynamic Resistance Characteristics for Weld Quality Improvement
Authors Sung-Kwan Kang ; Jae-Hun Jung ; Eui-Cheol Nho
DOI 10.6113/TKPE/2015.20.6.491
Page pp.491-497
ISSN 1229-2214
Keywords Resistance spot welding; Weld quality; Dynamic resistance characteristics
Abstract This study proposes a new control method for a resistance spot welding inverter to improve weld quality. The proposed method is based on the dynamic resistance characteristics of steel sheets to be welded. A point in the second peak value of the dynamic resistance occurs during one shot of the welding current flow. A constant voltage control is applied from zero to the peak point, and a constant current control is adopted from the peak point to the end of the shot. The mixed mode control of the constant voltage and current guarantees high weld quality. Experiments are conducted with a 5 kA power supply and 0.5 mm steel sheets to compare quality. Experimental results show that weld quality is improved more than 10 times that of the conventional control method.