| 摘要 |
PURPOSE:To eliminate the zero error of a generator by flowing an exciting current through an exciting coil having a time constant shorter than the always using exciting coil when the current of the generator does not pass zero point for the period longer than the prescribed time. CONSTITUTION:A voltage regulator AVR flows an exciting current through an exciting coil EX1 so that the voltage of a generator G becomes the set value. A discriminator A flows an exciting current through an exciting coil EX2 having a time constant shorter than that of the exciting coil EX1 when the current of the generator G does not pass zero point for longer than the prescribed time. When the current becomes zero point, a circuit breaker CB is broken. In this manner, the zero mistake can be eliminated merely by controlling the rise of the internal voltage after a malfunction is detected. Accordingly, the effects in stability and economy given to the system and the breakers can be increased. |
