| 摘要 |
PROBLEM TO BE SOLVED: To provide a power supply improved in a peak factor and an output- fluctuation at the time of a power fluctuation. SOLUTION: An inverter circuit 1, comprising a couple of switching elements Q1, Q2 connected between the output of a commutating circuit DB through diodes D1, D2, is configured such that a DC-cut capacitor C1, a resonance-load circuit 3 and a series circuit of a primary winding of a drive transformer DT1 are connected between the contact of the switching elements Q1, Q2 and one of the output ends of the rectifier circuit DB, and such that secondary windings of the drive transformer DT1 are respectively connected to the control ends of each of the switching elements Q1, Q2. A pulse-width control circuit 4 controls a switching operation of the switching elements Q1, Q2 in a section where the absolute value of an AC-power voltage is not less than a predetermined voltage, and also controls an ON-width of the switching element Q2. In a section where the absolute value of the AC-power voltage is less than the predetermined value in the meantime, the switching of the switching elements Q1, Q2 is self-operated by the feedback in the drive transformer DT1. |
