Clutched steam turbine low pressure sections and methods therefore

Abstract

Solutions for clutching steam turbine low pressure sections are disclosed. In one embodiment, a system includes: a first low pressure steam turbine including a first shaft; a second low pressure steam turbine including a second shaft; a clutch for coupling and uncoupling the first shaft and the second shaft; a conduit for delivering a working fluid to the first low pressure steam turbine and the second low pressure steam turbine; a valve within the conduit, the valve having an open position and a closed position, the closed position preventing flow of the working fluid to the second low pressure steam turbine; and a controller for operating the clutch and the valve, the controller uncoupling the second shaft from the first shaft and closing the valve in response to the first and second low pressure steam turbine attaining a predetermined low part load.

1 . A steam turbine system comprising:
 a first low pressure steam turbine including a first shaft;   a second low pressure steam turbine including a second shaft;   a clutch for coupling and uncoupling the first shaft and the second shaft;   a conduit for delivering a working fluid to the first low pressure steam turbine and the second low pressure steam turbine;   a valve within the conduit, the valve having an open position and a closed position, the closed position preventing flow of the working fluid to the second low pressure steam turbine; and   a controller for operating the clutch and the valve, the controller uncoupling the second shaft from the first shaft via the clutch and closing the valve in response to the first and second low pressure steam turbine attaining a predetermined low part load.   
     
     
         2 . The steam turbine system of  claim 1 , further comprising a steam turbine section coupled to the first low pressure steam turbine by the first shaft. 
     
     
         3 . The steam turbine system of  claim 2 , further comprising a generator coupled to the first low pressure steam turbine and the second low pressure steam turbine. 
     
     
         4 . The steam turbine system of  claim 3 , further comprising a first condenser operably connected to the first low pressure steam turbine. 
     
     
         5 . The steam turbine system of  claim 4 , further comprising a second condenser operably connected to the second low pressure steam turbine. 
     
     
         6 . The steam turbine system of  claim 1 , wherein the controller includes an electro-mechanical device. 
     
     
         7 . A combined cycle power plant system comprising:
 a gas turbine operably connected to a first generator;   a heat exchanger operably connected to the gas turbine;   a steam turbine section operably connected to the heat exchanger; and   a steam turbine system operably connected to the steam turbine section, the steam turbine system including:
 a first low pressure steam turbine including a first shaft; 
 a second low pressure steam turbine including a second shaft; 
 a clutch for coupling and uncoupling the first shaft and the second shaft; 
 a conduit for delivering a working fluid to the first low pressure steam turbine and the second low pressure steam turbine; 
 a valve within the conduit, the valve having an open position and a closed position, the closed position preventing flow of the working fluid to the second low pressure steam turbine; and 
 a controller for operating the clutch and the valve, the controller uncoupling the second shaft from the first shaft via the clutch and closing the valve in response to the first and second low pressure steam turbine attaining a predetermined low part load. 
   
     
     
         8 . The combined cycle power plant system of  claim 7 , further comprising a second generator operably connected to the steam turbine system. 
     
     
         9 . The combined cycle power plant system of  claim 8 , wherein the second generator is coupled to the first low pressure steam turbine. 
     
     
         10 . The combined cycle power plant system of  claim 7 , further comprising a first condenser operably connected to the first low pressure steam turbine. 
     
     
         11 . The steam turbine system of  claim 10 , further comprising a second condenser operably connected to the second low pressure steam turbine. 
     
     
         12 . The steam turbine system of  claim 7 , wherein the controller includes an electro-mechanical device. 
     
     
         13 . A method of operating a steam turbine system, the method comprising:
 uncoupling a second low pressure steam turbine from a first low pressure steam turbine using a clutch, the uncoupling being in response to the first and second low pressure steam turbine attaining a predetermined low part load.   
     
     
         14 . The method of  claim 13 , wherein the first low pressure steam turbine includes a first shaft and the second low pressure turbine includes a second shaft, and wherein the first shaft and the second shaft are capable of coupling and uncoupling via a clutch. 
     
     
         15 . The method of  claim 13 , further comprising:
 preventing flow of a working fluid to the second low pressure steam turbine using a valve, the preventing being in response to the first and second low pressure steam turbine attaining a predetermined low part load.   
     
     
         16 . The method of  claim 15 , further comprising performing the preventing and the uncoupling substantially simultaneously. 
     
     
         17 . The method of  claim 15 , further comprising controlling the preventing and the uncoupling using a controller. 
     
     
         18 . The method of  claim 17 , wherein the controller includes an electromechanical device.