| 摘要 |
PURPOSE:To prevent sudden increase in turbine output by a method wherein a limit follow-up allowance setter is provided in order to control allowable variation allowance of a speed governing signal based on deviation between a preset signal and an actual speed signal. A regulating valve is controlled by a lower value selected out of a sum of output of the follow-up allowance setter and the preset signal, and a speed regulating signal. CONSTITUTION:Revolving speed of a turbine 1 on which a generator 2 is connected directly is detected by a speed sensor 3 so that its output is input into an adder 20 to add it to a reference speed alpha. The resultant value is input into an adder 21 through a control arithmetic unit 10. Output of the arithmetic unit 10 and output of a setter 18 are added up in the adder 21 and its output, i.e. a speed governing signal is input into a low value selector 11. At the same time, output b from the follow-up allowance setter 8 and output e from setter 18 described above are added up in an adder 19 and the resultant value is input into the low value selector 11. A lower value signal selected by the low value selector 11 can prevent sudden increase in turbine output by controlling a regulating valve 12 through an output amplifier 12. |
