| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a power supply switching device for economically executing a switching operation of an AC power supply unit. <P>SOLUTION: The power supply switching device switches from an AC power supply unit to another AC power supply unit to supply AC power to a load apparatus when synchronization is established between the voltage, frequency, phase and voltage phase rotation direction of the AC power outputted from the previous AC power supply unit and those of the AC power outputted from the new AC power supply unit. The switching device detects the AC power supplied by the previous AC power supply unit and the AC power supplied by the new AC power supply unit respectively via transformers 16, 17, and inputs them to a phase check circuit 7 for comparing the phases. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
