| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent a voltage and frequency from being switched during operation and protect a load side apparatus from a damage, by a method wherein a voltage switching means and a frequency switching means are separated from a control power supply in accordance with an engine start command and, after the engine is stopped, a control power supply switch is opened once and then re-closed to be connected to the control power supply. SOLUTION: If a frequency or a generated voltage is changed after the start command of an engine is outputted, the engine is stopped and, after a control power supply 7 is cut off by a control power supply switch 6, the control power supply 7 is closed again by the control power supply switch 6 and the frequency or the voltage is changed to a required frequency or a required voltage. With this constitution, even if a voltage changeover switch 8 or a frequency changeover switch 13 are switched mistakenly, the voltage or the frequency is not changed and a load side apparatus can be protected from a damage.</p> |
