Output control method for gas-shielded arc welding, welding system, welding power source, and welding control device

A welding system comprising:

• a welding control device and a welding power source and for performing gas-shielded arc welding in which a tip-to-work distance changes during the welding,
• wherein at least one of the welding control device and the welding power source has a torch position detector to determine a welding torch position during the welding,
• wherein the welding power source has a correction-amount calculation circuit to calculate a correction current for feedback control,
• wherein the correction-amount calculation circuit includes at least one of
• a first controlling expression in which an instantaneous-voltage error value Dv1 serving as a difference between an instantaneous-output-voltage setting value Va and an output-voltage detection value Vd is multiplied by a first gain G1, and
• a second controlling expression in which an average-voltage error value Dv2 serving as a difference between an output-voltage setting value Vs and an average-output-voltage detection value Vave in a preset period is multiplied by a second gain G2, wherein the correction-amount calculation circuit sets at least one of the first gain G1 and the second gain G2 based on a torch-position detection value determined by the torch position detector, and
• wherein the correction-amount calculation circuit calculates the correction current based on at least one of the first controlling expression and the second controlling expression.

A welding power source for performing gas-shielded arc welding in which a tip-to-work distance changes during the welding, the welding power source comprising:

• a torch position detector to determine a welding torch position during the welding;
• and
• a correction-amount calculation circuit to calculate a correction current for feedback control,
• wherein the correction-amount calculation circuit includes at least one of
• a first controlling expression in which an instantaneous-voltage error value Dv1 serving as a difference between an instantaneous-output-voltage setting value Va and an output-voltage detection value Vd is multiplied by a first gain G1, and
• a second controlling expression in which an average-voltage error value Dv2 serving as a difference between an output-voltage setting value Vs and an average-output-voltage detection value Vave in a preset period is multiplied by a second gain G2, wherein the correction-amount calculation circuit sets at least one of the first gain G1 and the second gain G2 based on a torch-position detection value determined by the torch position detector, and
• wherein the correction-amount calculation circuit calculates the correction current based on at least one of the first controlling expression and the second controlling expression.