Modelling for control of a jet engine compressor variable stator vanes hydraulic actuator

In this paper we develop a control oriented model of a hydraulic servo system for the actuation of the variable stator vanes of a jet engine compressor. We first present a non-linear model derived from physical equations. We then develop a simpler piecewise-affine switching linear model which is suitable for the purpose of controller optimisation, system identification, and fault detection. The switching linear model is assessed by comparison with the response of a full nonlinear simulator.