| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power supply unit for arc processing capable of achieving output stabilization during low output. <P>SOLUTION: When an output request is large, PWM control is executed which adjusts on-pulse durations Wm, Ws of respective control pulse signals to be output to switching elements TR1, TR2 of an inverter circuit and switching elements TR3, TR4 of an auxiliary switching circuit interlocking therewith. When an output request is small, the PWM control is switched to PSM control which adjusts a difference α between mutual phases of respective control pulse signals being a pair between the inverter circuit and the auxiliary switching circuit. <P>COPYRIGHT: (C)2013,JPO&INPIT |
