초록 ▼

A method is disclosed for operating a steam turbine using turbine reserve capacity for attaining operation at elevated loads. In a preferred form of the invention, a bypass overload valve is provided in parallel with the steam admission control valves but is connected to discharge steam to a lower p

A method is disclosed for operating a steam turbine using turbine reserve capacity for attaining operation at elevated loads. In a preferred form of the invention, a bypass overload valve is provided in parallel with the steam admission control valves but is connected to discharge steam to a lower pressure stage of the turbine. During operation of the turbine at less than full load, the bypass overload valve is maintained closed and the control valves are positioned to sustain a preselected load. As load on the turbine increases, the control valves are increasingly opened until they have all reached their fully opened position corresponding to a nominal rated capacity of the turbine. Then, at the discretion of operating personnel, the bypass overload valve is fully opened while simultaneously one or more of the control valves is throttled to offset any steam passing through the bypass overload valve in excess of the amount required to sustain the preselected turbine load. A throttling reserve is thus established on the control valves which may then be positioned toward their fully opened position to achieve greater power output.

대표청구항 ▼

A method of operating a steam turbine delivering power to a connected load and adapted to receive steam from a steam generating source, the turbine having a plurality of control valves for controlling the admission of steam to higher pressure stages of the turbine and having a bypass overload valve

A method of operating a steam turbine delivering power to a connected load and adapted to receive steam from a steam generating source, the turbine having a plurality of control valves for controlling the admission of steam to higher pressure stages of the turbine and having a bypass overload valve connected to receive steam from the steam source and to discharge such steam to a power pressure stage of the turbine, said method comprising the steps of: (a) maintaining said bypass overload valve closed while controllably positioning said control valves to admit steam to the turbine to sustain a preselected power load; (b) increasingly opening said control valves with increasing load demand on the turbine until all valves of said plurality of control valves have reached a fully opened position; (c) fully opening said bypass overload valve while substantially simultaneously controllably positioning at least one of said control valves toward a closed position sufficient to offset steam flow through said bypass overload valve in excess of that required to sustain the turbine load; and (d) further increasing the power output of the turbine by controllably positioning said plurality of control valves toward said fully opened position.