| 摘要 |
PURPOSE:To enable the stabilized employment of a turbine, by switching from automatic control to manual control only when a mutual deflection of duplicated signals of a controller of a turbine and a deflection of a variation rate of a control signal is large. CONSTITUTION:Duplicated control signals 1 and 2 are supplied to a low value preferential circuit 3 and an automatic control signal 4 is obtained. On one hand, a deflection signal 11 between the control signals is supplied to a switching part 12, through which a large deflection signal 23 is inputted into a switching part 12 when the signal 11 is larger than a fixed point; and a deflection signal 17 of a variation rate of a control signal obtained through variation rate arithmetic unit parts 14 and 15 and a subtractor 16 is inputted into a switching part 18, through which a large deflection signal 22 of a variation rate is outputted when the signal 17 is larger than a fixed value. When both signals 22 and 23 are generated, a switching contact point 6 is switched to a manual control signal 8 side by an abnormal signal discriminating part 5. Then when an abnormal control signal does not follow to a control signal for a normal load decrease, automatic control without making an unnecessary switch to manual control can be performed. |
