| 摘要 |
<p>PURPOSE:To supply a sufficient output pulse to a thyristor of an exciter when the voltage of an electric power system is lowered by providing an insufficient voltage detector, a synchronization detector and a back-up power supply circuit thereat. CONSTITUTION:There are provided an insufficient voltage detector 16 for detecting the voltage drop of a power supply voltage, a synchronization detector 18 for operating synchronously with the power supply voltage, and a back-up power supply 15 in the phase control circuit 5 for controlling a pulse applied to the gate of a thyristor exciter 3 for supplying field current to a synchronous generator 1. When both the contacts 17 and 19 are simultaneously closed by the operations of the detectors 16 and 18, a capacitor 8 is charged by the back-up power supply 15 to excite a pulse transformer 11 upon conduction of a thyristor 7. Accordingly, even if there occurs voltage drop in the system, sufficient pulse can be applied to the system to exactly control the phase of the generator.</p> |
