| 摘要 |
<p>PURPOSE: A power supply and a power supply for arc machining are provided to be applied to input power having a plurality of different voltage values and to stabilize an arbitrary low output. CONSTITUTION: A DC(Direct Current) converter circuit(12) rectifies and equalizes input AC(Alternating Current) power and converts the input AC power into a DC voltage. An inverter circuit(13) includes a bridge circuit and converts the DC voltage into a fixed AC voltage. A PWM(Pulse Width Modulation) control part adjusts the ON pulse width of a control pulse signal provided to first through fourth switching elements, and adjusts the ON pulse width of a control pulse signal provided to fifth through eighth switching elements according to the adjusted width. A phase shift control part adjusts phase difference of the two control pulse signals provided to the corresponding switching elements. A control switching part actuates the PWM control part if high output is required and actuates the phase shift control part if low output is required.</p> |
