Steam turbine with steam storage system

Abstract

A steam turbine system including a steam source for generating a steam flow, a high pressure turbine providing a first steam exhaust, a low pressure turbine fluidly coupled to the high pressure turbine, and, a steam storage system having an inlet for receiving a portion of the first steam exhaust from the high pressure steam turbine and storing in the steam storage system, the steam storage system having an output with a pressure relief valve for discharging a second steam exhaust to the low pressure turbine.

What is claimed is: 
     
         1 . A steam turbine system, comprising:
 a steam source for generating a steam flow;   a high pressure turbine providing a first steam exhaust;   a low pressure turbine fluidly coupled to the high pressure turbine;   a steam storage system having an inlet for receiving a portion of the first steam exhaust from the high pressure steam turbine and storing in the steam storage system, the steam storage system having an output with a pressure relief valve for discharging a second steam exhaust to the low pressure turbine.   
     
     
         2 . The steam turbine system of  claim 1 , wherein the steam source includes a first superheater and a second superheater, the steam turbine system further comprising an interstage desuperheater operatively arranged between the first and second superheaters. 
     
     
         3 . The steam turbine system of  claim 1 , further comprising a desuperheater between the first exhaust of the high pressure steam turbine and the inlet of the steam storage system. 
     
     
         4 . The steam turbine system of  claim 1 , further comprising a heat exchanger operatively coupled between the first exhaust of the high pressure steam turbine and the inlet of the steam storage system. 
     
     
         5 . The steam turbine system of  claim 4 , wherein the steam source is a heat recovery system generator (HRSG) having a low pressure system, and the heat exchanger is configured to output into LP steam from the low pressure system of the HRSG. 
     
     
         6 . The steam turbine system of  claim 1 , further comprising an intermediate pressure steam turbine fluidly coupled to the high pressure steam turbine and the low pressure steam turbine. 
     
     
         7 . The steam turbine system of  claim 6 , further comprising a second desuperheater operatively coupled between the steam source and the intermediate pressure steam turbine. 
     
     
         8 . The steam turbine system of  claim 7 , wherein the steam source is an HRSG having an intermediate pressure system, and the second desuperheater is a water injection operatively coupled to the intermediate pressure system and configured to control the temperature of the inlet to the intermediate pressure steam turbine. 
     
     
         9 . The steam turbine system of  claim 1 , wherein the steam source is a heat recovery steam generator (HRSG) and is operatively coupled to a gas turbine. 
     
     
         10 . The steam turbine system of  claim 9 , wherein there are a plurality of HRSGs as steam sources operatively coupled to a plurality of gas turbines, wherein the plurality of HRSGs generate the steam flow. 
     
     
         11 . The steam turbine system of  claim 1 , wherein the steam storage system is a steam storage tank. 
     
     
         12 . The steam turbine system of  claim 1 , wherein the steam storage system includes a plurality of steam storage tanks. 
     
     
         13 . A power plant, comprising:
 a steam turbine system, having:
 a heat recovery steam generator (HRSG) for generating a steam flow; 
 a high pressure turbine providing a first steam exhaust;
 a low pressure turbine fluidly coupled to the high pressure turbine; and, 
 
 a steam storage system having an inlet for receiving a portion of the first steam exhaust from the high pressure steam turbine and storing a storage steam, the steam storage system having an output with a pressure relief valve for discharging a second steam exhaust to the low pressure turbine. 
   
     
     
         14 . The power plant of  claim 13 , wherein the HRSG includes a first superheater and a second superheater, the steam turbine system further comprising an interstage desuperheater operatively arranged between the first and second superheaters. 
     
     
         15 . The power plant of  claim 13 , further comprising a gas turbine operatively coupled to the HRSG. 
     
     
         16 . The power plant of  claim 13 , further comprising an intermediate pressure turbine. 
     
     
         17 . The power plant of  claim 13 , further comprising a second desuperheater between the HRSG and the intermediate pressure turbine. 
     
     
         18 . A method, comprising:
 feeding a first portion of a first exhaust steam from a high pressure steam turbine to a steam storage system, and feeding a second portion of the steam to an HRSG;   storing the first portion of the steam in the steam storage system;   outputting, with a pressure relief valve, a steam flow from the steam storage system to a low pressure steam turbine; and,   controlling the temperature of the exhaust steam from the steam storage system by adding superheated steam from the first steam exhaust, wherein the steam storage discharges superheated steam to the low steam turbine.   
     
     
         19 . The method of  claim 18 , further comprising running a combined cycle power plant in part load, and providing an interstage desuperheater between a first superheater and a second superheater of the HRSG. 
     
     
         20 . The method of  claim 18 , further comprising providing a heat exchanger configured between the high pressure steam turbine and the inlet of the steam storage system.