| 摘要 |
<P>PROBLEM TO BE SOLVED: To speedily detect a power failure, to reduce use current of an apparatus, and to increase temporal enduring rate to an instant power failure without enlarging capacity of a capacitor constituting a DC power supply when power supply stops from an AC power supply. <P>SOLUTION: The arrangement is provided with an inverter circuit 9 constituted of a switching element 7 and a regeneration device 8; and an inverter device 6 constituted of a control unit 9 formed of a microcomputer 5. When power supply from the AC power supply 1 stops, a voltage monitoring device 10 monitors voltage of the capacitor 3 being the first DC power supply for driving a three phase DC brushless motor 4. When voltage drops to a prescribed value, occurrence of the power failure is judged. The microcomputer 5 reduces use current of the apparatus 11, reduces supply current from the capacitor 3 and the second DC power supply 12, and makes the arrangement to be proof against long time power failure. <P>COPYRIGHT: (C)2007,JPO&INPIT |
