| 摘要 |
PROBLEM TO BE SOLVED: To solve a problem that in a frequency-modulation type power source device for arc machining in which a reactor resonance tank LCF is used, a low output current can not be kept because the output current rapidly increases when the arc length varies under a low output current and a low output voltage, that causes such as a weld defect as a burn through in a welding of thin plates. SOLUTION: The method for controlling a power source for arc machining and the power source device are that an output current Io is controlled by adjusting the impedance value Z of the reactor resonance tank LCF by varying the frequency (inverter frequency) f of a high frequency AC pulse voltage of an inverter full-bridge circuit INV according to a signal value Si for controlling switch which is calculated by the set value Ir of the output current, and the output current Io is also controlled by operating so as to change over the base current of a secondary switch TRA or TRD into a saturated region and an active region. |
