Nitrogen-cooled dynamoelectric machine system and related method

Abstract

Various embodiments of the invention include systems and methods for cooling a dynamoelectric machine. In some embodiments, a system is disclosed including: at least one of a nitrogen separation unit (NSU) or an air separation unit (ASU) for extracting nitrogen from an inlet air source; a nitrogen expander fluidly connected with the at least one of the NSU or the ASU, the nitrogen expander for expanding the extracted nitrogen; and a dynamoelectric machine fluidly connected with the nitrogen expander, the dynamoelectric machine configured to receive the expanded nitrogen for cooling the dynamoelectric machine.

We claim: 
     
         1 . A system comprising:
 at least one of a nitrogen separation unit (NSU) or an air separation unit (ASU) for extracting nitrogen from an inlet air source;   a nitrogen expander fluidly connected with the at least one of the NSU or the ASU, the nitrogen expander for expanding the extracted nitrogen; and   a dynamoelectric machine fluidly connected with the nitrogen expander, the dynamoelectric machine configured to receive the expanded nitrogen for cooling the dynamoelectric machine.   
     
     
         2 . The system of  claim 1 , further comprising at least one steam turbine operably connected to the dynamoelectric machine. 
     
     
         3 . The system of  claim 1 , further comprising at least one gas turbine operably connected to the dynamoelectric machine. 
     
     
         4 . The system of  claim 1 , wherein the dynamoelectric machine further includes a nitrogen outlet for exhausting the expanded nitrogen after the cooling of the dynamoelectric machine. 
     
     
         5 . The system of  claim 1 , wherein the nitrogen expander is configured to cool the extracted nitrogen before providing the expanded nitrogen to the dynamoelectric machine. 
     
     
         6 . The system of  claim 1 , wherein the inlet air source includes an exhaust flue gas having nitrogen and carbon dioxide. 
     
     
         7 . The system of  claim 1 , wherein the inlet air source includes ambient air. 
     
     
         8 . A method comprising:
 extracting nitrogen from an inlet air source;   expanding the extracted nitrogen; and   cooling a dynamoelectric machine using the expanded, extracted nitrogen.   
     
     
         9 . The method of  claim 8 , further comprising providing the expanded, extracted nitrogen to an exhaust vent after the cooling of the dynamoelectric machine. 
     
     
         10 . The method of  claim 8 , further comprising providing the expanded, extracted nitrogen to another component distinct from the dynamoelectric machine after the cooling of the dynamoelectric machine. 
     
     
         11 . The method of  claim 8 , wherein extracting includes separating the nitrogen from one of ambient air or an exhaust flue gas. 
     
     
         12 . The method of  claim 8 , wherein the expanding of the extracted nitrogen includes cooling the extracted nitrogen in a nitrogen expander. 
     
     
         13 . The method of  claim 8 , wherein extracting includes separating the nitrogen from carbon dioxide in the inlet air source. 
     
     
         14 . A system comprising:
 at least one of a nitrogen separation unit (NSU) or an air separation unit (ASU) for extracting nitrogen from an inlet air source;   a nitrogen expander fluidly connected with the at least one of the NSU or the ASU, the nitrogen expander for expanding the extracted nitrogen;   a dynamoelectric machine fluidly connected with the nitrogen expander, the dynamoelectric machine configured to receive the expanded nitrogen for cooling the dynamoelectric machine; and   a control system operably connected to the at least one of the NSU or the ASU, the nitrogen expander and the dynamoelectric machine, the control system configured to perform the following:
 monitor a temperature indicator of the dynamoelectric machine; and 
 modify an amount of nitrogen extracted from the inlet air source in response to determining the temperature indicator deviates from a predetermined threshold. 
   
     
     
         15 . The system of  claim 14 , further comprising at least one steam turbine operably connected to the dynamoelectric machine. 
     
     
         16 . The system of  claim 14 , further comprising at least one gas turbine operably connected to the dynamoelectric machine. 
     
     
         17 . The system of  claim 14 , wherein the dynamoelectric machine further includes a nitrogen outlet for exhausting the expanded nitrogen after the cooling of the dynamoelectric machine. 
     
     
         18 . The system of  claim 14 , wherein the nitrogen expander is configured to cool the extracted nitrogen from the inlet air source before providing the expanded nitrogen to the dynamoelectric machine. 
     
     
         19 . The system of  claim 14 , wherein the inlet air source includes an exhaust flue gas having nitrogen and carbon dioxide and the NSU extracts the nitrogen from the exhaust flue gas. 
     
     
         20 . The system of  claim 14 , wherein the inlet air source includes ambient air and the ASU extracts the nitrogen from the ambient air.