高压双电磁阀控制燃油系统控制策略研究

摘要

根据双电磁阀控制燃油系统的工作原理,讨论了可采用的溢流控制阀(SV)和针阀控制阀(NCV)控制模式；针对不同的控制模式,分析了从控制信号到燃油喷射的延时特性,揭示了动态喷嘴启喷压力( NOP)随转速的变化规律,探讨了双阀燃油系统的燃油喷射特性,并进行试验.结果表明SV相对于NCV的控制角度差值能够有效地改变NOP、NCP(喷嘴关闭压力)和MFIP(平均燃油喷射压力)的大小.着重探讨了双阀燃油系统的控制算法,阐述了NCV目标喷油持续期和目标喷油提前角的控制方法,提出了NOP控制及双阀燃油系统总体控制策略,并给出了反映NOP随转速和控制角度差值变化而变化的NOP控制MAP,为双阀燃油系统的整车应用提供了基础.%According to the working principle of the two-actuator fuel injection system, the available control modes were discussed firstly, the delay time from control signal to fuel injection was analyzed, variation characteristics of NOP at different speeds were figured out and injection characteristics were explored then, the experimental results showed that the difference between SV and NCV control angle could change the value of NOP, NCP and MFIP effectively. Finally, the control algorithms were explored emphatically, calculating method for NCV desired SOI and durations were introduced and the control strategy of two-actuator fuel injection system was proposed, and the NOP control MAP that reflected it tendency with different speeds and the control angle difference was analyzed, which provided the basic theory for vehicle purpose.