Design And Simulation Research For Big Displacement Motorcycle Engine Electronic Control Fuel Injection And Ignition System

This thesis takes the LJ377MV motorcycle engine developed by the Luoyang Northern Enterprises Group Co. Ltd as the research target.Considering the structure and performance characteristics of the engine, control model of the engine is built, including sensors'model selecting, singlechip's model selecting, operator's model selecting, fuel injection mode fixing, intake amount measuring, control mode of system parameters, working condition fixing, fuel injection control, ignition control, idle control, different working conditions managing, conmmunication between PIC and PC machine and malfunction diagnosing.Meanwhile, the design of relative hardware and software for the engine electronic control system is finished. Within the hardware design, the signal collecting circuit and driving circuit is simulated and debuged to realize collection for the engine parameters and control for ignition, fuel injection and idle, etc.; within the software design, main program, working condition distinguishing program, A/D amount collection program, MAP searching and value inserting program, PIC and PC machine serial communication program is designed. Meanwhile, managing software is designed primarily to realize collection of engine running parameters and read-write of MAP. Considering of the bad work condition for motorcycle engine with interferential sources, to make sure of the normal work for engine electronic control system, hardware anti-jamming design and software anti-jamming design is made for the electronic control system by analyzing interferential sources.Through simulating and debuging of the hardware and software, the results indicate that this system can collect and display all kinds of analog signal,digital signal and can realize the control for drive circuits. Through esatablishing engine simulation modle, the MAP data of elcctronical control system is gained which is written in the unit of ECU. According to different working condition, the value of fuel injection and ignite advance angle is gained,then put them into the simulation of engine work process and calculate the power and torque of different working condition, and then contrast to the data of reference engine.The result vadidates the simulation model is satistified.Through simulation experiment, The result vadidates that the circurt of fuel injection and ignition is correct and the electronical control system can run reliablly.