涡扇发动机的一类大包线系统建模

Modeling of a Large Envelope System for Turbofan Engine

基于涡扇发动机部件级模型,研究了具有非线性和时变特性的涡扇发动机非线性变参数系统建模问题。通过系统辨识的方法,以高压转子转速为调度变量,得到典型工作点的多项式非线性系统。在此基础上,借鉴增益调度思想,将高度和马赫数拟合成系统的时变参数,利用回归算法,建立大包线慢车以上非线性变参数(Nonlinear parameter-varying,NPV)模型。仿真表明,采用该方法建立的非线性系统与部件模型在单个转速状态时误差小于0.05%,非线性变参数模型与部件模型在大包线范围内的误差小于1%,验证了本文方法的可行性和有效性。

Based on the component-level model of turbofan engine,a modeling method for turbofan engine with nonlinear and time-varying characteristics is investigated.A polynomial nonlinear system with typical operating points is obtained by the method of system identification and taking the high pressure rotor speed as the scheduling variable.And based on the regression algorithm,a nonlinear parameter-varying model is established by the gain scheduling idea and taking the height and Mach number as the scheduling variable.The simulation results show that the error for nonlinear system and the component model established by the method is less than 0.05%in a single speed state,and the error for the nonlinear parameter-varying model and the component model is less than 1%in large envelope,which proves the feasibility and effectiveness of the proposed method.