Research On The Adaptive Control Technology Of Variable Cycle Aeroengine

The new type of variable cycle engine(VCE)of variable geometry flow path is one of the most promising propulsion systems,its wide range of flight envelope and the changing work mode requires the multi-variable control system to achieve the high-precision requirements.In order to master the key technologies of this advanced aircraft engine control system,especially promote the application of advanced control theory in the field of VCE control,this paper systematically studies the adaptive control method and its application in steady-state multi-variable control of VCE.Therefore,aiming at the problems of multi-variable control,modeling uncertainty and external random interference of VCE,the main research contents are as follows:1.Research on modeling method of nonlinear component model for VCE.Under the framework of component modeling,development of geometric characteristics,the mapping relationship of the external channel steady-state characteristics,the performance calculation methods of variable geometric component,then solve the initial value dependency and convergence efficiency problems encountered in the iterative process of the engine's common working equation by the proposed hybrid algorithm combined particle swarm with Broyden quasi-Newton which is switched by divergence coefficient based on power balance equation,energy balance equation and flow balance equation.Finally,establish high-precision VCE mathematical model.And the accuracy is improved by the simulation results contrasted with Gasturb,then analysis the VCE state and dynamic performances.2.Research on the overall scheme of VCE control system.Summary the limit scope includes the range of compressor surge margin,CDFS surge margin,turbine front temperature,and max-min fuel flow,and determine the optimal working condition of the different VCE work modes.Also,the cruise control law of the double-channel operating mode is analyzed,and the transition law of the acceleration and deceleration plan and the mode switching scheme is summarized.In addition,the whole state linear model of VCE is deduced based on the method of small deviation from Taylor unfolds,and the linear model and simulations at some steady-state design points in flight envelope are given,to lay the model data foundation for the deeply relevant study on multi-variable control method for VCE.3.Research on the design method of multivariable model reference adaptive controller with modeling uncertainties and its application on VCE.As to solve the problem of multivariable controller design with modeling uncertainties of variable cycle engine,give a augmented model reference adaptive tracking control compensation design method under the RSLQR optimal law.First,analysis the influence of penalty function on root trajectory of the system.Based on the designed linear models,under the based controller feedback structure,determine reference model with expected closed-loop dynamic system and establish adaptive laws with modeling uncertainties under Lyapunov function stability proof,then achieve zero tracking error and eventually improve the dynamic tracing with uncertainties.Finally,applies this method to VCE and gives simulation analysis.4.Research on the design method of multivariable robust adaptive and its application on VCE.As to solve the problem of multivariable robust adaptive controller design with external disturbances which caused by the variable cycle engine's wide range of flight envelope,give a adaptive law based on projection.Firstly,the adaptive control methods by dead-zone modified,? modified,e modified are designed and simulated to verify the control performance with different external disturbances.Then the robust adaptive control design method modified by projection is proposed to solve the problems of control parameters drift and system integral saturation.The projection modified method limits the solutions of the state error's dynamic equations within the setting range of convex sets,so as to ensure the system unanimously bounded and realize the state error's dynamic equations was not greater than zero.Finally,Finally,applies this method to VCE and gives simulation analysis.5.Research on the verification of adaptive control technology for VCE.Based on the small deviation from the established steady-state linear model,the control effects are compared by different control algorithms,and the performance of the proposed robust adaptive controller with projection modified is verified.Then,on the basis of studying the mathematical modeling technology and the design method of adaptive controller of VCE,the performance simulation model of VCE with C-mex of S-function is designed,and the proposed adaptive controller method is effectively verified via simulated on this model.The numerical simulation examples are given in the design of the VCE adaptive control method in the corresponding chapters.The simulation results show that: the mathematical modeling method,the adaptive controller design method for VCE proposed in this paper is feasible and effective,the method has a certain practical engineering value on VCE control system.