Gas Turbine Combustor and Operating Method Thereof

Abstract

A gas turbine combustor has a chamber supplied with fuel and air and a multi-burner having a plurality of burners provided with an air hole plate having a plurality of air holes, and fuel nozzles for supplying fuel to the air holes in the air hole plate; the multi-burner is made up of a center burner disposed in the center and a plurality of outer burners around the center burner, the outer burners are divided into inner fuel nozzles and outer fuel nozzles to separately supply fuel through fuel systems, and the fuel is supplied to the fuel nozzles in the center burner or to the fuel nozzles in the center burner and the inner fuel nozzles in the outer burners disposed around the center burner in a partial load condition in which the load is lower than that of when all the fuel systems are used to supply fuel.

1 . A gas turbine combustor comprising: a chamber for mixing and burning supplied fuel and supplied air to generate combustion gas;
 an air hole plate located in an upstream side of the chamber, forming a plurality of air holes for supplying the air;   a plurality of fuel nozzles for supplying the fuel to the plurality of air holes formed in the air hole plate,   wherein the air holes are disposed in the downstream side of the fuel nozzles that one of the fuel nozzles is paired with one of the air holes; and   a plurality of burners made up of the plurality of air holes and the plurality of fuel nozzles in pairs,   characterized in that,   the plurality of burners are comprised a center burner disposed on an axis of the gas turbine combustor and a plurality of outer burners installed around the center burner,   the center burner is fixed to a first fuel supply system for supplying the fuel to the fuel nozzles in the center burner,   the plurality of outer burners is fixed to a second fuel supply system for supplying the fuel to the fuel nozzles in outer burner's inner portions which are inner regions of specific outer burners among the outer burners,   the plurality of outer burners is fixed to a third fuel supply system for supplying the fuel to the fuel nozzles in outer burner's inner portions which are inner regions of outer burners other than the specific outer burners,   the plurality of outer burners is fixed to a fourth fuel supply system for supplying the fuel to the fuel nozzles in outer burner's outer portions which are outer regions of the outer burners,   wherein when a gas turbine is operated in a low load or partial load condition, the fuel is supplied to the fuel nozzles in the center burner or to the fuel nozzles in the center burner and in the outer burner's inner portions which are the inner regions of the specific outer burners among the plurality of outer burners through the first to the fourth fuel supply systems selected based on the operation condition of the gas turbine.   
     
     
         2 . The gas turbine combustor according to  claim 1 ,
 wherein the plurality of outer burners are arranged in two groups of the specific outer burners having first outer burner's inner portions supplied with the fuel through the second fuel supply system and the other outer burners having second outer burner's inner portions supplied with the fuel through the third fuel supply system,   every one of the plurality of outer burners has the outer burner's outer portion in the outer side of the outer burner, and the outer burner's outer portions make up a group to be supplied with the fuel through the fourth fuel supply system.   
     
     
         3 . The gas turbine combustor according to  claim 2 ,
 wherein the specific outer burners having the first outer burner's inner portions supplied with the fuel through the second fuel supply system are the outer burners disposed near crossfire tubes connecting neighboring gas turbine combustors among the plurality of outer burners installed.   
     
     
         4 . The gas turbine combustor according to  claim 2 ,
 wherein the specific outer burners having the first outer burner's inner portions supplied with the fuel through the second fuel supply system and the other outer burners having the second outer burner's inner portions supplied with the fuel through the third fuel supply system are disposed alternately.   
     
     
         5 . The gas turbine combustor according to  claim 2 ,
 wherein a plurality of the gas turbine combustors are installed, and   when the gas turbine combustors are ignited, the fuel is supplied to the center burner installed to the gas turbine combustor to be ignited and the outer burner's inner portions which are the inner regions of the outer burners disposed near the crossfire tubes connecting the gas turbine combustor to be ignited and the gas turbine combustors adjacent to the gas turbine combustor to be ignited.   
     
     
         6  An operating method of a gas turbine combustor having a chamber for mixing and burning supplied fuel and supplied air to generate combustion gas; an air hole plate located in an upstream side of the chamber, forming a plurality of air holes for supplying the air; a plurality of fuel nozzles for supplying the fuel to the plurality of air holes formed in the air hole plate, wherein the air holes are disposed in a downstream side of the fuel nozzles that one of the fuel nozzles is paired with one of the air holes; and a plurality of burners made up of the plurality of air holes and the plurality of fuel nozzles in pairs, wherein the plurality of burners are comprised a center burner disposed on an axis of the gas turbine combustor and a plurality of outer burners installed around the center burner,
 the center burner is fixed to a first fuel supply system for supplying the fuel to the fuel nozzles in the center burner, 
 the plurality of outer burners is fixed to a second fuel supply system for supplying the fuel to the fuel nozzles in outer burner's inner portions which are inner regions of specific outer burners among the outer burners, 
 the plurality of outer burners is fixed to a third fuel supply system for supplying the fuel to the fuel nozzles in outer burner's inner portions which are inner regions of the outer burners other than the specific outer burners, and 
 the plurality of outer burners is fixed to a fourth fuel supply system for supplying the fuel to the fuel nozzles in outer burner's outer portions which are outer regions of the outer burners, 
 the operating method of a gas turbine combustor comprising the steps of: 
 supplying the fuel through the first fuel supply system to the fuel nozzles disposed in the center burner to burn the chamber when a gas turbine is operated in a low load condition; 
 supplying the fuel additionally through the second fuel supply system to the fuel nozzles disposed in the outer burner's inner portions which are the inner regions of the specific outer burners among the plurality of outer burners to burn the chamber when the gas turbine is operated in a partial load condition with load increased more than that of the low load gas turbine; 
 supplying the fuel additionally through the third fuel supply system to the fuel nozzles disposed in the outer burner's inner portions which are the inner regions of all other outer burners among the plurality of outer burners except for the specific outer burners to burn the chamber when the gas turbine is operated in a partial load condition with load increased more than that of said partial load gas turbine; and 
 supplying the fuel additionally through the fourth fuel supply system to the fuel nozzles disposed in the outer burner's outer portions which are the outer regions of all the outer burners to burn the chamber when the gas turbine is operated in a full load condition with load further increased.