Models and the Control System Design Cycle

Abstract

In this chapter techniques for mathematical modelling of gas turbine engines are presented considering the different stages in the life cycle from design, to demonstration, to commercial control system development, and finally through to in-service use. Through these stages the fidelity of the engine model is refined, as more information becomes available. The chapter thus considers evolution of models from the initial stages of design, where the general characteristics of the engine are known, to the latter stages, where a controller is tailored to the specific characteristics of the engine. The models required over the life cycle are discussed in greater detail in subsequent chapters. The key modelling stages are as follows:

• nonlinear performanee-based modelling;

• dynamic characteristic modelling;

• linear dynamic modelling;

• piecewise linear dynamic modelling for real-time development.