Patent ID: 6370863
Filing Date: 2002-04-16
Classification: F02C,F23R

Abstract:
A method of operating a gas turbine, in which a gaseous fuel is burned in a combustion chamber and the hot combustion gases which are produced in the process are directed through the gas turbine, comprising the steps of:feeding gaseous fuel to the combustion chamber through a plurality of controllable burners fluidly arranged in parallel and in a plurality of segments arranged angularly inside the combustion chamber, each segment including a radially inner burner and a radially outer burner, each burner being operable in a mode selected from the group consisting of a premix mode in which the fuel is injected laterally into the burner through premix holes, a pilot mode in which the fuel is injected into the burner through a central pilot hole, and both; wherein the plurality of burners are fluidly arranged into at least two groups of burners, each of the burners of each segment being a member of at least one of the at least two groups of burners; and individually actuating a group of burners as a function of the operating state of the gas turbine; wherein a first group comprises less than half the total number of burners, and the burners of this first group are operated in the premix mode, and wherein a second group is formed by the rest of the burners of the combustion chamber, and the burners of this second group are operated in the premix mode, and wherein a third group is formed by the burners of the second group, and wherein the burners of the third group are operated in the pilot mode.