Patent ID: 8510014

Claim:
A gas turbine control method for controlling a gas turbine plant and a gas turbine thereof, the method comprising: a first step of detecting process variables which affect combustion vibrations by a vibration measuring unit that measures the combustion vibrations occurring in each combustor of the gas turbine as pressure fluctuations or accelerations, a fuel property measuring unit that measures components or calorific value of fuel supplied to the combustor, and a process variables measuring unit that measures the process variables regarding fuel and air supplied to the combustors; a second step of analyzing a vibration level for each vibration frequency bandwidth on a basis of a plurality of the process variables measured by the process variables measuring unit, information regarding the components or the caloric value of the fuel measured by the fuel property measuring unit, and the pressure fluctuations or the accelerations obtained by the vibration measuring unit, so as to establish mathematical models by mathematically modeling combustion vibration characteristics based on the analyzed data; a third step of using a countermeasure decision unit for determining the adjustments for the operation of the gas turbine and outputting the adjustments to a controller wherein the controller increases or decreases the flow rate of the fuel or the air supplied to the combustor so as to maintain an operation condition under which the combustion vibrations are unlikely to occur based on the mathematical models; a fourth step of dividing and storing each of said process variables of the gas turbine obtained in the first step into a plurality of databases in response to the detected values of the components or the calorific value of the fuel, wherein said process variables are divided and stored into the plurality of databases such that adjacent databases have a common interval which is an area where a boundary region of each of the adjacent databases having data regarding the components or the calorific value overlaps; a fifth step of setting a threshold value in a part of the common intervals; and a sixth step of retrieving the detected values of the components or the calorific value of the fuel from each of the databases with the detected values of the process variables obtained in the first step to perform approximation treatments of the combustion vibration characteristics, wherein, regarding the data in the common interval of the adjacent databases, data is retrieved from the common interval of the database of which the detected values of the components or the calorific value of the fuel are continuous, and the approximation treatments are performed on the retrieved data, so as to decrease discontinuity in mathematically modeling the combustion vibration characteristics in a process of the approximation treatments.