| 摘要 |
PURPOSE:To maintain present operation as it is without tripping even when a main circuit gets out of order by providing a turbine control device with a backup circuit which has the function of feedback control of rotational speed and keeping automatic balance with the main circuit. CONSTITUTION:The first controller 10 receives a rotational speed command signal S11 from a control device 11 of an upper stage and an actual rotational speed signal S34 and sends out a control signal S10. Variation 31 between output signals from the first and the second controllers 10, 20 is inputted to an integrator 21, while a variation S22 of its output signal S21 from an actual rotational speed signal S34 is inputted to the second controller 20. Normally, a selector 33 selects the S10 side, and a switch 32 is closed, then a signal S20 follows and coincides with S10. When the first controller 10 gets out of order, the switch 32 is opened and the selector 33 is changed over to the signal S20 side so that the rotational speed may be controlled to its value right before the controller is getting out of order. |
