| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To protect a prime mover and a synchronous generator by preventing the field current of an exciter from becoming excessive even though the rotational speed of the synchronous generator is low when the prime mover is started and supplying a certain exciter field current from an device other than an automatic voltage regulator to cause the synchronous generator to output a voltage even when the automatic voltage regulator is faulty. <P>SOLUTION: The rotational speed or field current of a synchronous generator body 7 is measured. When the result of measurement determines that there is a possibility of overexcitation in an alternating-current exciter 8 or the AC voltage regulator 13 is faulty, the setting of a changeover switch 38 for power supply to the exciter is changed from the automatic voltage regulator 13 to a constant excitation power supply 35 in a different system by an excitation power supply switching means 34, and the field current is thereby reduced to a low value so that the alternating-current exciter 8 is not brought into overexcitation state. Overheating of the exciter is thereby prevented when the synchronous generator 6 is started and overspeed of the prime mover 1 and the brushless synchronous generator 6 is prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
