Research On Reset Adaptive Control Of Aeroengine

Aeroengine is a complicated pneumatic thermodynamic system with strong nonlinearity.As for now,a linear model of single point and a LPV model for the modeling of aeroengine can get its nonlinear characteristics and be accessible for design and analysis of engine control system.However,both the two methods both have their limitations: The linear model of single point is not applied to all the working point throughout the flight envelope;the LPV model is unable to guarantee the stability of the system in theory at present.Therefore,establishing an engine model,which can reflect the whole engine working process and be suitable for the design of control algorithm,has great significance for the development of aeroengine.This paper establishes a simple and reliable model of aeroengine and carried out the design research of relevant control algorithm based on that model.The main work of this paper is divided into three parts:(1)This paper studies the status tracking problem of the traditional aircraft engine model reference adaptive control and points out the system over-regulation problem that may occur in the process of adaptive control.Firstly,a mathematical model is established based on the parameters of a certain aeroengine type.And the traditional adaptive law is obtained by the model reference adaptive method.Adding a reset mechanism on the basis of the control system to guarantee the system can reset the adaptive law in case of excessive regulation problem.And two theorems have been given to prove the stability of the reset adaptive control system.(2)In order to satisfy the actual demand of the aeroengine,an engine switching model which contains all the working points in the whole engine work package line is built.Establishing the switching reference model and the error switching system according to the expected performance requirements.Then the adaptive control law is designed and updating the reset adaptive laws for each subsystems.Finally,designing a kind of switching signalwhich ensures engine's control system has a good dynamic performance and the stability of the error switching system in the working process.(3)For improving the adaptive control efficiency of switching reset adaptive control system,this paper achieves the estimated value of the unknown parameters that satisfy the requirements of performance by online identification method.And taking a verification both in theory and MATLAB/SIMULINK when the engine control system under disturbance.