| 摘要 |
<P>PROBLEM TO BE SOLVED: To switch from an uninterruptible power supply device that has failed to a sound device by an overlap type switching device, with no degradation in reliability of supplying power to a load facility. <P>SOLUTION: The uninterruptible power supply system includes uninterruptible power supply devices 11 and 12 having a bypass switching function, output branching circuits 71 and 72 for branching the outputs of the uninterruptible power supply devices 11 and 12 into two systems through a switch, overlap switching devices 81 and 82 capable of switching power supplying to load facilities 91 and 92 with no interruption, with feeding of power from both output branching circuits being possible, and voltage/frequency command means 101 which issues at least one of the output voltage command and an output frequency command of the uninterruptible power supply devices 11 and 12. The voltage/frequency command means 101, in case a switching preparation command is received from the overlap switching device 81 and 82, and any one of the uninterruptible power supply devices 11 and 12 fails, switches an output voltage command that is issued to a sound uninterruptible power supply device to a voltage of a bypass power supply of the failed uninterruptible power supply device from a predetermined constant voltage. <P>COPYRIGHT: (C)2011,JPO&INPIT |
