摘要 |
<p>A steam turbine power plant having a feedwater heater (8, 9, 10), a boiler (30), a steam turbine (33, 34, 35) driven by steam generated in the boiler (30), and a condenser (37) for condensing steam exhausted from the steam turbine. An extracting steam pipe (12,13, 4) is provided which includes a control valve (16, 15, 44) for extracting a steam from the steam turbine to the feedwater heater (8, 9, 10), with a controller (22) being provided for controlling an amount of the extracting steam in order to control a feedwater temperature flowing through the feedwater heater (8, 9, 10) at an adequate range when the plant is starting or stopping. By controlling the feedwater temperature, a thermal stress generated in the feedwater heater is reduced to below an allowable value so that it is possible to increase the working or service life of the feedwater heater and improve the reliability of the steam turbine plant while reducing the maintenance costs thereof.</p> |