| 摘要 |
<p>PURPOSE:To prevent the step-out of synchronous machines due to a mistake in operation of the excitation system is the switching, by means of a operation circuit which outputs the control command to vary the set output of the excitation device according to the difference in the outs of two excitation control devices by comparison. CONSTITUTION:When operation is switched from constant excitation control to automatic voltage adjustment, a changeover switch 2 - 5 is changed from the position ''constant excitation'' to ''switching''. At this point, the control circuit is turned on with contacts ''switching'' of an auxiliary relay 2 - 5 and a changeover switch 2 - 3, and then, a control switch is operated to control a variable resistor 1 - 3 for automatic voltage adjustment. When the output of an automatic voltage adjusting device 1 - 1 coincides that of a constant excitation control device 1 - 2, a control relay 1 - 6 works to light an indication lamp 2 - 2. When the switch 2 - 3 is turned to the position ''automatic voltage adjustment'', an auxiliary relay 2 - 1 works to close a contact 2 - 1a while allowing a contact 2 - 1b to open. With such an arrange ment, remote controlling can be done along with the prevention of the step-out.</p> |
