| High-pressure common rail fuel injection system is one of the key technologies to enable diesel engine more efficient and cleaner. Electronic control is the most important part to realize fuel injection's flexible control and fuel pressure's regulation. The Electronic control unit (ECU) and the development system for diesel engine based on microcomputer are studied in this thesis.The gross structure of ECU and main function of every part are introduced in this thesis. In order to save microprocessor resource, complex programmable logic device (CPLD) of MAX7000S series, the software MAX+plusII and the very high speed hardware description language (VHDL) are used in the research. After design, compilation, debugging and simulation, the hardware circuit function was realized. Finally the program was solidified into the CPLD device and was verified by the circuit experiment. DC-DC power supply unit is used to improve the electromagnetic response of the injector. To improve unit's performance, three parameters (capacitance, inductance and circuit frequency) and the control pulse are investigated by experiment based on the simulation result. The effects of these parameters on unit performances are concluded. The injection rate of injector and electromagnetic response is studied for different units.The Electronic control development system for diesel engine is designed to evaluate the performance of injector and high pressure fuel pump, also to obtain the required MAP. The function of signal acquisition, control signal generation and power drive is achieved through hardware design. Many measures of anti electromagnetic interference are also considered. According to the principle of modularization, the modules of engine control, display and pressure acquisition are accomplished. The calibration results of the injector reveal that the injector has satisfying linearity, small cyclical fluctuation and very high speed opening response.
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