Embedded Software Design Of Electronic Control Unit In SCR System

With the increasingly prominent environmental problems,gradually improved environmental protection laws and regulations,SCR system has been widely used in ships,automobiles and non-road machinery and other fields.As the soul of SCR system,the embedded software design is very important.Aiming at the main problems in the software architecture,function and development method of the embedded software of electronic control unit in SCR system,by using the method of combining theory with practice,this paper designs the embedded software of electronic control unit of SCR system from three aspects:(1)in terms of software architecture,after in depth understanding of the existing excellent embedded software architecture and considering the development costs and development cycle,then learn from Autosar architecture to design the three layer software architecture suitable for this system.Complete the driver and the middle layer software design based on TMS570LS0432 microcontroller.The middle layer software can avoid the coupling between the application layer software and the underlying driver software,which is convenient for software maintenance and upgrade(2)in terms of the function software,on the one hand,fuzzy immune PID control algorithm is used to realize the closed loop control of Adblue injection of SCR system which has nonlinear,large time delay and large inertia characteristics.Fuzzy immune PID controller enhanced the immunity of Adblue injection control.It is a kind of improvement to the Adblue injection control function.On the other hand,research and design a method to detect the state of the original NOx emission for engine in operation,to enrich the function of the software.(3)In terms of the development methodology,use the model based design method which improved the efficiency of software development,software quality,shorten the development cycle,reduced development costs,to realize the design of the fuzzy immune PID controller and the original NOx emission state detector.Then realize the automatic generation of embedded C code with product level.The embedded software of the electronic control unit of the SCR system is tested by hardware in the loop simulation(HIL),which can meet the design requirements.Realize the design of application layer software of TMS570 controller by MBD.