| 摘要 |
<P>PROBLEM TO BE SOLVED: To meet constant requirements for size and cost reductions in an uninterruptive power supply device of a commercial power supply system. <P>SOLUTION: A load 11 and a two way power converter 4 are connected to AC input terminals 1a, 1b, 1c through AC switches 2a, 2b, 2c. Storage means 5 is connected to the two way power converter 4. A power recovery switching control circuit 10 is provided. The power recovery switching control circuit 10 stops inverter feeding when a commercial current/voltage reaches a predetermined approximate range of an inverter voltage at amplitude and phase during power recovery and generates a signal for starting commercial feeding. Hence, an inverter feeding period can be shortened and the size and cost of the storage means 5 can be reduced. <P>COPYRIGHT: (C)2009,JPO&INPIT |
