Chaos Robust Control Strategy And Its Application In The Control Of Engine

A exploratory research about choosing those appropriate weighting functions for the robust control design problem is made, a new robust controller design strategy called chaos robust control strategy is proposed. The air fuel ratio of gasoline engine has a close relationship with its economic performance, its dynamic performance and the emissions performance. Precise control of air-fuel ratio is significant to improve combustion quality of gasoline engine, give full play to the combustion characteristics of fuel and reduce harmful emissions of gasoline engine.This work is supported by Open Fund Project of Jiangsu provincial key laboratory. A new chaos robust controller which can be used for transient air-fuel ratio control of gasoline engine is designed based on the chaos robust control strategy and the simulation is performed. The main work and innovations of the thesis are as follows:(1) A new robust controller design strategy called the chaos robust control strategy is proposed based on optimal H-infinity control theory and chaos optimization algorithm. And it is used for transient air-fuel ratio control of electronic fuel injection gasoline engine. Comparison of the results of simulations showed that the new chaos robust controller of EFI gasoline have strong robustness, small overshoot and short transition time and the accuracy of air-fuel ratio control is increased.(2) In order to verify the validity of the transient air-fuel ratio control system based on chaos robust control strategy. Its robust stability, its robust performance and the fragility of the controller are inspected. The results showed that the chaos robust controller used for the transient air-fuel ratio control of the gasoline engine can work normally when a certain perturbation exist in the system.(3) An accurate model of gasoline engine was built using the GT-power software which is dedicated to engine simulation. The co-simulation platform based on GT-Power/Simulink is established and the chaos robust controller of transient air fuel ratio is tested on it. The result showed that the chaos robust controller can be stabilized the air-fuel ratio around target value in the steady-state condition. When the throttle of gasoline engine changed suddenly, the controller can be adjust the fuel injection duration time quickly and the controlled error can be kept within the range of 4%.