Method for controlling fuel splits to gas turbine combustor

A method for scheduling a fuel split for a gas turbine combustor comprising:

• f. determining a target exhaust temperature corresponding to a desired nitrogen oxide (NOx) at a reference fuel split;
• g. determining an exhaust temperature error based on a comparison between a scheduled exhaust temperature and the target exhaust temperature;
• h. converting the exhaust temperature error to a projected NOx leveling fuel split adjustment;
• j. adjusting the reference fuel split using the projected NOx leveling fuel split adjustment;
• and
• applying the adjusted fuel split to determine fuel flow to the combustor,
• wherein the conversion of the exhaust temperature error to the projected NOx leveling adjustment further comprises:
• determining a projected NOx level from the exhaust temperature error;
• determining an adjusted Q factor as a ratio of a NOx level baseline request and the projected NOx level, and applying the adjusted Q factor to determine the projected NOx level adjustment.

A method for scheduling a fuel split for a combustor of a gas turbine comprising:

• a. determining a target turbine exhaust temperature corresponding to a desired NOx emission level from the gas turbine at a reference fuel split schedule, wherein the target exhaust temperature is based on at least one parameter of a group of parameters consisting of specific humidity, compressor inlet pressure loss and turbine exhaust back pressure;
• b. automatically determining an exhaust temperature error based on a temperature difference between a scheduled turbine exhaust temperature and the target turbine exhaust temperature;
• c. automatically converting the exhaust temperature error to a projected NOx level error at the reference fuel schedule for the entire combustor, and
• d. automatically converting the projected NOx level error to an adjustment to the reference fuel schedule for the entire combustor.

A method for scheduling a fuel split for a combustor of a gas turbine comprising:

• a. determining a target exhaust temperature corresponding to a desired NOx emission level from the gas turbine at a reference fuel split schedule, wherein the target exhaust temperature is based on at least one parameter of a group of parameters consisting of specific humidity, compressor inlet pressure loss and turbine exhaust back pressure;
• b. determining an exhaust temperature error based on a temperature difference between a scheduled exhaust temperature and the target exhaust temperature;
• c. converting the exhaust temperature error to a projected NOx level error at the reference schedule, and
• d. converting the projected NOx level error to an adjustment to the reference fuel schedule;
• wherein the reference fuel split schedule is determined for a base load condition at which the gas turbine is operating at full rated power.

A method for scheduling a fuel split for a combustor of a gas turbine comprising:

• a. determining a target exhaust temperature corresponding to a desired NOx emission level from the gas turbine at a reference fuel split schedule, wherein the target exhaust temperature is based on at least one parameter of a group of parameters consisting of specific humidity, compressor inlet pressure loss and turbine exhaust back pressure;
• b. determining an exhaust temperature error based on a temperature difference between a scheduled exhaust temperature and the target exhaust temperature;
• c. converting the exhaust temperature error to a projected NOx level error at the reference schedule, and
• d. converting the projected NOx level error to an adjustment to the reference fuel schedule;
• wherein the conversion of the temperature difference further comprises:
• deriving an adjusted Q factor as a ratio of a NOx base request and an adjusted NOx level derived from the temperature difference;
• applying the adjusted Q factor to the reference fuel split schedule to generate the adjustment to the reference fuel schedule.