| 摘要 |
PURPOSE:To eliminate the possibility of simultaneous disconnection of CVCF power supply and commercial power supply from a load by performing switching through a switching path which can not be closed simultaneously with a switching path associated with a slight time lag. CONSTITUTION:A CVCF power supply and a commercial power supply 2 feed a load 5 with power through a first AC switch 31, a second AC switch 32, a first switch 33, a second switch 34, a third switch 35 and a bypass switch 36. A micro overlap time is provided between the operation of the AC switch 31 and the AC switch 32 when switching is made between the CVCF power supply 1 and the commercial power supply 2. The bypass switch 36 is switched oppositely to the switch 33. The bypass switch 36 closes with micro time lag after opening of the switch 33. The switch 33 closes with micro time lag after opening of the bypass switch 36. |
