| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem in which although a plasma welding device ignites a pilot arc by generating a high frequency, the pilot arc is frequently extinguished because of a low no-load voltage before an arc is generated.SOLUTION: The present invention relates to a plasma welding power supply device comprising: a main power generation part which generates a main current; an output current detection circuit which detects the main current; a pilot generation part which generates a pilot arc current; a pilot current detection circuit which detects the pilot arc current; a main control circuit which controls the main power generation part based upon a value of a first output current; and a high-frequency generation circuit which generates a high-frequency high voltage. The pilot generation part is provided with a secondary switching element, a reactor, and a switch, and the main control circuit is configured to charge the reactor with electric power by turning on the secondary switching element and making a contact of the switch closed, and after the charging is completed, the contact of the switch is open and then the charged electric power with the pilot arc current is supplied to the torch.SELECTED DRAWING: Figure 1 |
