Development Of High Pressure Common-rail ECU Rapid Prototype Of Marine Medium-speed Diesel Engine

With depletion of conventional energy resources and increased pollution,governments and institutions introduce more stringent diesel engine emission regulations,which request a higher and higher engine performance of power,fuel consumption,exhaust,noise and so on.As a main developing direction,people are paying more and more attention to the high pressure common rail injection system.With a suitable ECU,this injection system able to control the fuel pressure,injection duration,injection speed flexibly,and optimize engine performance in the whole working conditions.The electronic control technology in our country is just starting out,it's significant and valuable to research and develop a high pressure common-rail electronic control system,which can provide a foundation for the research of engine control strategy.On the base of Flex-ECU and marine diesel engine high pressure common-rail HIL(hard-ware-in-loop)system,according to V-model development process,an electronic control unit was developed in this thesis used with NI c RIO and Lab VIEW as development platform.The four main contents of this paper are as follows:(1)Analyze the overall demand of electronic control unit(ECU)which used for marine medium-speed high pressure common-rail diesel engine.The engine working in the speed range of 300~1200r/min.Build the hardware platform with NI c RIO controller and I/O modules.Part the function blocks and Design the ECU software in the aspects of structure and data flow.(2)Develop the ECU software system uses Lab VIEW FPGA,the function blocks including signal acquisition module,signal processing module,engine position management module,fuel injection module,pressure control valve drive module and so on.Develop engine speed signal simulation module and test the ECU function blocks offline.The result shows that the ECU can accomplish data acquisition and engine position tracking.Fuel injection module can output injector drive signals according to setting parameters.Pressure control valve drive module can output PWM signal in different duty cycle.(3)Build the hardware-in-loop simulation system with ECU rapid prototype,a diesel engine simulation model and high pressure common-rail system,and test the performance of ECU.It shows that the HIL system operation well,engine model running smooth in the control of ECU,fuel injectors can spray fuel in proper order,PWM signal can drive pressure control valve to stabilize fuel pressure.(4)The open ECU platform is built with NI modular hardware,which can be easily expanded in processors,chassis and I/O ports.The ECU also can achieve high-speed data acquisition and control with FPGA,which can realize high determinacy hardware decisions with a fast temporal resolution of control loop in 25 ns.This thesis makes research on ECU rapid prototype of marine high-pressure common-rail medium-speed diesel engine in the aspects of hardware selection,software design,offline verification and HIL test and so on.The developed ECU supplies a basic platform and technical reference for further research on engine control strategies for marine medium-speed dual-fuel engine.