Testing and modeling gas turbines using multisine signals and frequency-domain techniques

摘要

The frequency-domain identification of gas turbine dynamics is discussed. Models are directly estimated from engine data and used to validate linearized thermodynamic models derived from the engine physics. This work is motivated by the problemspreviously encountered when using time-domain methods. A brief overview of frequency-domain techniques is presented and the design of appropriate multisine test signals is discussed. Practical results are presented for the modeling of the fuel feed toshaft speed dynamics of a twin-spool engine. The gathered data are analyzed and the frequency response functions of the engine are estimated. The identification of parametric s-domain models is discussed in detail and a comparison made between theidentified models and the linearized thermodynamic models. The influence of engine non linearities on the linear models is also examined.