Pre-mixing burner with integrated diffusion burner

Claim 1

Burner system for a gas turbine combustion chamber comprising (a) a pre-mixing burner with an integrated diffusion burner (b) the pre-mixing burner having a pre-mixing chamber into which chamber a main fuel nozzle and a feeding device for combustion air open, and which chamber is bounded at its downstream end by a flame retention baffle (c) the diffusion burner having a pilot fuel nozzle arranged in the central region of the flame retention baffle, (d) fuel control means including a load signal device which generates a signal in accordance with the load of the gas turbine, a fuel control device connected to and operating in response to the load signal device, a main fuel control valve through which fuel flows to the main fuel nozzle, a pilot fuel control valve through which fuel flows to the pilot fuel nozzle, said fuel control device connected to the main fuel control valve and to the pilot fuel control valve and operating in response to the load signal device controls the flow of fuel through the pilot fuel control valve exclusively from start of the gas turbine to a low load or idling speed or a small partial load of the gas turbine and thereafter to an upper range load of the gas turbine through both the main fuel control valve and the pilot fuel control valve, (e) said opening in the pre-mixing chamber for the feeding device for combustion air being the sole entrance for the entire combustion air required for the operation of the diffusion burner, and (f) said fuel control device connected to the main fuel control valve and to the pilot fuel control valve and operating in response to the load signal device above the upper range load of the gas turbine controls the flow of fuel through the main fuel control valve exclusively.