Design Of General Driving Platform For Electronic Control Fuel Injection System

With the increasing energy shortage and environmental crisis and the increasingly stringentengine emission regulations, energy conservation has become the most important motivation topromote the development of engine technology. The electronic control fuel injection technology isan effective means to meet the requirements of energy saving and emission reduction. Generally, theelectronic unit pump system and the high-pressure common rail system are most commonly used.Based on the ECU drive consistency and versatility of both systems, the paper designed generaldriving platform for electronic control fuel injection system, which can be applied to both systemsthrough different hardware and software configurations, with the advantages of strong adaptability,high reliability, and prospective industrialization.First，according to the characteristics of both fuel injection systems, the design objective andrequirement of general driving platform are proposed, and the general design of platform softwareand hardware systems is done. Furthermore, after high-speed solenoid valve driving simulationmodel was built with Simulink, the impact of the storage capacitance in the high-speed solenoidvalve driving circuit, the high-side drive voltage and maintaining the wave parameters on thereal-time response characteristics of the solenoid valve is analyzed. The effect of the boostinductance and the storage capacitor on the boost voltage in the boost circuit is studied. The analysisresults provide guidance for matching high-speed solenoid valve with different impedance.Then, the general driving platform hardware system design using the modular and platformmethod is completed after analyzing the simulation results. Based on the hardware design, thecontrol software is divided into three modules using modular and hierarchical design concept,namely the management module, the driving module and device module. Meanwhile the taskscheduling is controlled by foreground/background software architecture, and combined with thescheduling strategies of the priority preemptive and time slicing to structure the multitaskmechanism. After analysis of the structure and control strategy of the task module of the each layeris conducted in detail, the design of the software program is completed.Finally, the functional verification test of general driving platform is carried out and the enginematching test is implemented on pump test-bed. The results show that when matching two types ofhigh-speed solenoid valve, the output voltage ripples in the boost circuit are both less than threepercent, and the restoring time of the high-voltage power supply is less than0.25ms. The opening time of solenoid valve in the electronic unit pump is less than0.7ms, and its closing time is lessthan0.15ms. The opening time of solenoid valve in the injector in the common rail system is lessthan0.3ms, and its closing time is less than0.1ms. They both meet the real-time requirements ofthe high-speed solenoid valve driving. In the rail pressure controlling experiments, under thesimulative steady-state and instantaneous conditions, the steady-state rail pressure waves are lessthan2MPa, while the instantaneous ones are less than4MPa, which both meet the requirements ofthe rail pressure control.