APPARATUS AND METHOD FOR SWITCHING POWER SUPPLY

摘要

PROBLEM TO BE SOLVED: To provide a power supply switching apparatus capable of detecting the occurrence of power interruption and quickly switching power sources.

SOLUTION: The power supply switching apparatus includes a connecting means (change-over switch 40) that selectively connects either a first three-phase alternating-current power source or a second three-phase alternating-current power source to load equipment; rectifying means (bridge diodes 62g to 62i and bridge diodes 63g to 63i) that full wave-rectify all phases of the three-phase alternating current of at least either of the first three-phase alternating-current power source and the second three-phase alternating-current power source that is going to detect the occurrence of power interruption or a failure; detecting means (optical MOSFETs 67 and 68) that refer to a direct-current voltage obtained as the result of rectification by the rectifying means to detect the occurrence of power interruption; and control means (61e and 64e) that control the selecting means according to the result of detection by the detecting means.

COPYRIGHT: (C)2006,JPO&NCIPI