胡建功

（太原学院机电工程系，山西 太原 030032）

摘要：针对高压共轨电磁式喷油器喷孔变大或其它原因导致喷油量变大的问题，提出喷孔流量变动的在线诊断方法。通过对高压共轨燃油系统轨压变化基本原理，试验研究了转速、喷油提前角对瞬态轨压压降变化的影响，结果表明，转速和喷油提前角变化对高压共轨中瞬态轨压压降的影响属于正常范围。通过加电时间修正喷油脉宽，使理论喷油量和实际喷油量相符，研究了瞬态轨压的变化规律，并提出一套基于瞬态轨压来识别喷油器磨损的控制策略,通过轨压压降识别喷油器流量的变化。

关键词：高压共轨；加电时间；瞬态轨压；喷油脉宽

Abstract: To solve the issue of increased fuel injection quantity due to enlarged injector hole or other factors of high pressure common rail electromagnetic injector, an online diagnostic method of injector flow rate change is proposed. Based on the principle of rail pressure change of high pressure common rail fuel system, the effect of engine speed and injection timing on transient fuel rail pressure change is investigated. The results show that the impact of engine speed and injection timing on transient fuel rail pressure change is normal. The change in fuel rail pressure is studied by adjusting the injection pulsewidth through power supply time so that the theoretic injection quantity matches the actual injection quantity. A control strategy to identify the injector wear based on transient fuel rail pressure change is proposed. The strategy identifies injector flow rate change based on fuel rail pressure drop.

Key Words: high pressure common rail；power supply time；transient pressure；injection pulse width