method and device for schnellumschaltung of vormischbetrieb in the diffusionsbetrieb in a combustion chamber of a gas turbine with fuel gas powered

摘要

The method involves initiating one changeover criterion for changing from premix to diffusion mode if timely detection of a transient process which could lead to premix flame extinction occurs or the initiation of a second changeover criterion if timely detection occurs of a premix flame extinction. The first and second criteria involve transferring to changeover logic the displacement (Z) of the valve in the fuel feed line and the pressure in the combustion chamber(s) respectively. The drive logic (8) continually checks the input values against the entered criteria. If a criterion is fulfilled, the drive logic passes a drive signal to the servovalve (7) of a rapid changeover valve (3) in the combustion gas feed line.