| 摘要 |
PROBLEM TO BE SOLVED: To provide a stable electric arc having a specified shape by adding a control operation to a difference between each of reference values for electric arc current and voltage satisfying an electric arc characteristic and a value detected by a detector, mixing obtained control amounts with each other to perform common compensation and controlling an electric arc driving mechanism. SOLUTION: An electric arc voltage is detected and fed back by an electric arc voltage detector 9, and based on deviation from an electric arc voltage reference value, an operation is performed by a voltage controller 11 such that an electric arc voltage reaches a specified value. On the other hand, an electric arc current is detected and fed back by an electric arc current detector 10, and based on deviation from an electric arc reference value, an operation is performed by a current controller 12 such that an electric arc current reaches a specified value. Electric arc voltage control is based on a negative feedback loop, electric arc current control is based on negative feedback, and a current is reduced with respect to the increase of an electric arc gap, in other words, a signal mixing controller 13 is used for providing a polarity opposite that of electric arc voltage control. |
