| 摘要 |
PURPOSE:To optimize the efficiency of a combined plant comprising a gas and a steam turbines, by effecting speed government control for only a prescribed unit whose speed regulation differs in a prescribed frequency fluctuation range from that of the other unit. CONSTITUTION:A speed government signal calculator 43 for a first unit operates in accordance with such a speed regulation as not to effectuate speed government control in a prescribed rotational frequency region. A first speed government signal 28 and a set load signal 31 are added together by an adder 34 to produce a required load signal 44. At a normal turbine speed, the set load signal 31 is selected by a changeover contact 45 not to effectuate the speed government control. When the prescribed rotational frequency region is exceeded, the signal 44 is selected to effectuate the speed government control. The same control is performed for a second unit. For a third unit, a third speed government signal calculator 50 generates a speed government signal 51 on the basis of the difference between a speed signal 41 and a set speed signal 39. The set load signal 33 is added to the speed government signal 51 to generate a required load signal 37. According to this constitution, the first and the second units can be operated at the maximum efficiency in a prescribed range. |
