| 摘要 |
<p>PURPOSE:To prevent a synchronous generator from tripping, by judging whether malfunction is due to the abnormality on a system side or due to the fault of an automatic voltage regulator in the generator and by changing over to other queuing system only when it is found to be the fault of the automatic voltage regulator. CONSTITUTION:An automatic voltage regulating device AVR 28 supplies the deviation signal between the terminal voltage of a synchronous generator 1 detected by a voltage transformer 6 and the set point to a thyristor 4 for excitation through a gate pulse generator 14. When the reactive power comes to the leading side in operating with the AVR 28 and gets to the activating level of a low excitation limiting device 9 and further to the activating level of a low excitation protection device 16, an abnormal signal is outputted. At this time, in case the variation of the terminal voltage of the synchronous generator is lowered, it is judged as a fault of the AVR 28 and a changeover circuit 12 is changed over from the AVR 28 to a field current control device 29. In case the variation of the terminal voltage goes up, an automatic follow-up system is locked.</p> |
