The Design Of Control Unit In Diesel Engine SCR Dosing System

Many Countries have introduced laws and regulations to deal with the increasingly serious environmental problems. For diesel engines, to meet the State IV and Stage V emissions requirements, the SCR (Selective Catalytic Reduction) technology roadmap is becoming the mainstream. Although there have been domestic SCR systems matching with some types of diesel engines, but all have the problem that main components within the system rely on imports, especially the adblue dosing&injection system. Therefore, building an independent adblue dosing&injection system, will essentially upgrade the level of autonomy of the domestic diesel engine SCR system.Basing on the diesel engine SCR system (embedded OBD functions) jointly launched by WHUT and Wuhan Tianlan Engine Emission Technology Co., Ltd., the author firstly, with considering the functional requirements of adblue dosing&injection system, and analysising the structural characteristics of existing typical adblue dosing&injection systems, design the structural forms of the dosing&injection system and mechanical parts within the system; and then, focusing on hardware and software, design the control unit within the system; finally, construct a functional testing platform to validate the design of the dosing&injection system.Based on the existing technical conditions, this thesis completes the following:(1)control unit hardware design: based on the the hardware requirements of SCR control, the OBD functionas and dosing&injection operation, the design of control unit hardware;(2)control unit software design: with full consideration of the platform versatility, combined with the software process of the system, the design of control unit software;(3)functional test platform design: based on the design process and design principle, the design of functional testing platform to the system.