| 摘要 |
PURPOSE:To eliminate an exciting current transformer exclusively for excitation by supplying the current from an instrument current transformer to an exciting coil when the output current of a generator is abruptly increased or when the voltage of the generator is decreased. CONSTITUTION:A thyristor controller 11 normally conducts a bidirectional thyristor 12 to shortcircuit the output of an instrument current transformer 9. On the other hand, an automatic voltage regulator 5 controls the conduction of a thyristor 6 in response to the output of an instrument transformer 4. When a shortcircuit trouble occurs in the output circuit of a generator 1 and the detected voltage value at the transformer 4 is abnormally decreased or the detected current value of the transformer 9 is abruptly increased, the controller 11 interrupts the thyristor 12, and supplies the output of the transformer 9 through a rectifier 13 to an exciting coil 2. In this manner, the current necessary to recover the voltage of a generator or to operate a protecting relay is supplied. |
