The Transactions of the Korean Institute of Power Electronics (전력전자학회논문지)

The Korean Institute of Power Electronics (전력전자학회)
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A Novel Control Method of Resistance Spot Welding Inverter using Dynamic Resistance Characteristics for Weld Quality Improvement

용접품질 향상을 위한 저항 스폿 용접용 인버터의 동저항 특성을 이용한 새로운 제어기법

  • Kang, Sung-Kwan (Dept. of Electrical Engineering, Pukyong National University) ;
  • Jung, Jae-Hun (Dept. of Electrical Engineering, Pukyong National University) ;
  • Nho, Eui-Cheol (Dept. of Electrical Engineering, Pukyong National University)
  • Received : 2015.10.07
  • Accepted : 2015.10.28
  • Published : 2015.12.20
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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.

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References

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