Apparatus and method for active control of oscillations in gas turbine combustors
First Claim
1. A method of operating a gas turbine combustor in a lean premixed combustion mode, wherein the combustor has discrete fuel and air delivery systems, a fuel/air premixer zone, and a reaction zone, comprising:
- supplying air from an air supply system through at least one opening into the premixer zone of the combustor, said air having a predetermined pressure upstream of said opening;
supplying fuel from a fuel supply system, including a nozzle having a fuel passage and a discharge orifice for delivering said fuel, into the premixer zone of the combustor;
reducing the pressure of said fuel upstream of said fuel discharge orifice to approximately said predetermined pressure, said air supply opening and said fuel discharge orifice having substantially the same pressure drop;
sensing at least one of pressure, temperature and velocity fluctuations in said reaction zone and generating a feedback signal; and
actuating a control device operatively coupled to said fuel passage downstream from a locus of said pressure reduction and upstream of said fuel discharge orifice to affect fuel flow therein in response to said feedback signal, whereby pressure fluctuations in the premixer zone resulting from fuel/air concentration oscillations are substantially minimized or eliminated.
1 Assignment
0 Petitions
Accused Products
Abstract
An apparatus and method of applying active, closed loop control to reduce combustion driven pressure oscillation in a single or multi-chamber combustion system in an industrial gas turbine, to increase operability and life of the parts, and in such a way as to require minimal input power. The invention combines the passive control of a two stage nozzle with active control thereby to reduce the requirements on the control device. This allows selection of a control device which will have an adequate life in an industrial environment and yet require minimal input power.
95 Citations
15 Claims
-
1. A method of operating a gas turbine combustor in a lean premixed combustion mode, wherein the combustor has discrete fuel and air delivery systems, a fuel/air premixer zone, and a reaction zone, comprising:
-
supplying air from an air supply system through at least one opening into the premixer zone of the combustor, said air having a predetermined pressure upstream of said opening;
supplying fuel from a fuel supply system, including a nozzle having a fuel passage and a discharge orifice for delivering said fuel, into the premixer zone of the combustor;
reducing the pressure of said fuel upstream of said fuel discharge orifice to approximately said predetermined pressure, said air supply opening and said fuel discharge orifice having substantially the same pressure drop;
sensing at least one of pressure, temperature and velocity fluctuations in said reaction zone and generating a feedback signal; and
actuating a control device operatively coupled to said fuel passage downstream from a locus of said pressure reduction and upstream of said fuel discharge orifice to affect fuel flow therein in response to said feedback signal, whereby pressure fluctuations in the premixer zone resulting from fuel/air concentration oscillations are substantially minimized or eliminated. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. Apparatus for stabilizing combustion in a gas turbine combustor operable in a lean premixed mode, and having a premixer zone and a reaction zone, comprising:
-
an air supply system including an opening for delivering air into the premixer zone of the combustor and having a predetermined pressure upstream of said opening;
a nozzle including a fuel passage and a discharge orifice for delivering fuel into the premixer zone;
a pressure reducer upstream of said fuel discharge orifice for reducing the fuel pressure upstream of said fuel discharge orifice to approximately said predetermined pressure, said air supply opening and said fuel discharge orifice having substantially the same pressure drop, a sensor operatively coupled to said reaction zone to sense at least one of pressure, temperature and velocity fluctuations in said reaction zone and to generate a feedback signal; and
a control device operatively coupled to said fuel passage of said nozzle downstream from said pressure reducer and upstream of said fuel discharge orifice to affect fuel flow in the nozzle in response to said feedback signal, whereby pressure fluctuations in the premixer zone resulting from fuel/air concentration oscillations are substantially minimized or eliminated. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15)
-
Specification