Homogenous charge compression ignition (HCCI) engine combustion timing control method based on linear model and sliding mode controller

Abstract

The invention provides a homogenous charge compression ignition (HCCI) engine combustion timing control method based on a linear model and a sliding mode controller. According to a discrete nonlinear model, a multiple linear regression method is selected to fit all parameters of a state equation, and a state equation of a linear discrete system is obtained. A black-box model is designed by using a back propagation (BP) neural network to correct errors of the linearized model. According to the black-box model, the combustion timing thetapCA50, the temperature of an induction manifold Tman, the pressure of the induction manifold Pman and the fuel oil equivalence ratio phi which are obtained through the linear model prediction of the HCCI engine serve as input, and the revised combustion timing thetaCA50 serves as output. An ideal combustion timing signal thetadCA50 of the corresponding linear model is searched for and obtained through a binary search method by using the black-box model and an ideal combustion timing signal theta~dCA50 of the actual HCCI engine. In addition, the discrete sliding mode controller with a kalman filter is designed by using the ideal combustion timing signal thetadCA50 and the linearized model. According to the method, the precision of the combustion timing of the linear model prediction, the speediness and the accuracy of the tracking ideal input of the combustion timing are ensured.

Description

technical field [0001] The invention belongs to the field of combustion timing control of a Homogenous Charge Compression Ignition (HCCI) engine, and specifically relates to the linearization processing of a combustion timing model of a Homogenous Charge Compression Ignition (HCCI) engine and the design of a combustion timing control method. Background technique [0002] The homogeneous compression ignition engine combines the advantages of the spark ignition engine and the compression ignition engine, and has the advantages of high fuel utilization, low nitrogen oxides and particulate emissions, etc. [1,2] Compared with traditional engines, it can increase fuel utilization by 15-20%, reduce nitrogen oxide emissions by 90-98%, and reduce particulate emissions by nearly 100%. [3] . [0003] In order to give full play to the advantages of the HCCI engine, it is necessary to burn 50% of the fuel corresponding to the crankshaft angle (combustion timing: θ CA50 ) is controlled ...

AI Technical Summary

Problems solved by technology

Due to the complexity of the linearization of the discrete nonlinear model, there are relatively few controllers designed for the discrete linear state equation of the HCCI engine

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