Patent ID: 7930890
Filing Date: 2011-04-26
Classification: F01D,F02C,F05D,F23N

Abstract:
1. A method for protecting a gas turbine installation from overheating and for detecting a flame extinction in a combustion chamber, in which air is compressed in a compressor unit and, after being admixed with fuel, is ignited as a fuel/air mixture in the combustion chamber and is burnt, to create a hot gas flow which sets a turbine stage in rotation downstream of the combustion chamber comprising: measuring, upstream of the turbine stage, at least one of pressure p determining a time change of the measured pressure as a pressure gradient (p′); determining a variable derived from the pressure gradient by integration of the determined pressure gradient within a time window of variable integration duration; determining the time window by a start and an end time point; defining the start and the end time point by the determined pressure gradient; triggering the start time point when a desired start pressure gradient is overshot by the determined pressure gradient; setting the end time point when an end pressure gradient is undershot; selecting a maximum positive or minimum negative integral value as a threshold value by the pressure gradient; comparing the variable derived from the pressure gradient with the threshold value and; generating a signal when the maximum positive threshold value is overshot or the minimum negative threshold value is undershot by an increment value which is obtained by the integration of the determined pressure gradient within the time window.