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Mixed Mode Control of Constant Power and Constant Current for Resistance Spot Welder using Dynamic Resistance Characteristics

동저항 특성을 이용한 저항 스폿 용접기의 정전력과 정전류의 혼합모드 제어

Kang, Sung-Kwan;Jung, Jae-Hun;Nho, Eui-Cheol
강성관;정재헌;노의철

  • Received : 2015.10.13
  • Accepted : 2015.10.30
  • Published : 2015.11.01

Abstract

A new mixed mode control of constant power and constant current for resistance spot welding inverter is proposed to improve the weld quality. The conventional control scheme adopts constant current or constant power control mode, however, it is not easy to guarantee the high weld quality because of the nonlinear resistance characteristics of the welding point. The proposed method utilizes the nonlinear characteristics by measuring the dynamic resistance in real time. Therefore, it is possible for the welder to be controlled adaptively depending on the welding state. Experimental results show that the proposed control scheme improves the weld quality by 6.8 times compared with the conventional constant current mode control.

Keywords

Dynamic resistance characteristics;Weld quality;Constant current and power control

References

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