| 摘要 |
PURPOSE:To prevent an adjusting valve from being exessively actuated upon sudden drop in system frequency in an automatic follow-up device for a load limiter in a turbine generator, so that operation of a power plant is stabilized, by changing the follow-up speed of the limiter in dependence upon the variation rate of the desired value of the follow-up. CONSTITUTION:During the operation of a governor for a turbine generator, the deviation (d) between a summation signal of an adjusting valve open degree signal (a) and a follow-up width set signal (c), and a load limiting width set signal (b) is delivered to a limiter drive motor 4 for driving the limiter in order to make a load limiter normally follow a desired value. Further, the valve open degree signal (a) is delivered to a variation rate detecting circuit 5. The deviation (e) between the output of the variation rate detecting circuit 5 and the output of a signal generating circuit 6 is delivered to a signal limiter 7. The larger the signal (e) or the variation rate of the valve open degree, the smaller the output (d') of the signal limiter 7 is fed to the motor 4, thereby the follow-up speed of the load limiter is made lower and therefore, an adjusting valve is prevented from being exessively opened even upon sudden drop in system frequency. |
