Software Design Of Low Speed Diesel Engine Control System Based On Automatic Code Generation

Electronic control technology has huge potential in improving economic and dynamical performance and decreasing emissions of low-speed diesel engine.However,the traditional development method of electronic control system is hard to meet the rapid and efficient development demands of the low-speed diesel engine electronic control system due to the high costs and long cycle.In contrast,the technique of control system design based on model and automatic code generation method provides a real time and efficient platform,where the control strategy functions of diesel engine can be verified quickly by means of simulation in the early phases of controller design.Meanwhile,with the automatic code generation technology,the model of electronic control system can be transformed into C code.Thus,this paper intends to achieve the development of automatic code generation tool based on the mechanism of Matlab/Simulink RTW Embedded Coder with the consideration of the functional requirements of the low-speed diesel engine electronic control system.At the same time,this paper also completes the design of low-speed diesel engine control strategy and verifies it under such environment.Firstly,the overall scheme of the low-speed diesel engine control system is designed by studying the electronic control system architecture of the advanced foreign low-speed diesel engine.And the functions of the main control unit and cylinder control unit for the low-speed diesel engine are analyzed in details.Meanwhile,the signal interface of the main control unit and the cylinder control unit are designed,and the data transmission mode is determined.Then,the automatic code generation environment for the NXP MPC5644 A micro-controller is set up with Matlab/Simulink software via studying the principles of automatic code generation.And the controller model is translated into embedded C code through the system target files and control files,which are compiled in the Matlab/Simulink software platform.In addition,the underlying driver code of ECU is encapsulated through the S-Function and TLC files and the design of the custom driver module library are completed,including I/O module,A/D module,CAN driver module and fuel injection driver module.So that,it can integrate the underlying driver code with the model code for the controller software easily.At the end,the control strategy models of the main control unit and the cylinder control unit are established using the technology of graphical programming under the Matlab/Simulink software platform,and the ECU controller software is generated by the automatic code generation tool.Moreover,in order to verify the functions of the control system,the experimental validation is performed based on PXI Hardware-in-the-loop(HIL)simulation platform.The experimental results demonstrate that the controller model established in Simulink can be compiled into embedded C code for target processor through the automatic code generation tool.Meanwhile,it can be concluded that the controller software satisfies the functional demands of electronic control system for low-speed diesel engine.