多缸柴油机瞬时转速与各缸一致性分析

Analysis the transient speed and the uniformity of multi-cylinder diesel engine

为使ECU通过提取瞬时转速完成发动机各缸一致性控制,提出每隔30℃A提取一个发动机瞬时转速,并以DK4A多缸柴油机为试验平台,测量发动机在1 600 r/min稳态工况下,不同负荷下常用的每隔6℃A和提出的每隔30℃A的瞬时转速。每隔30℃A得到的瞬时转速曲线能很好地表征瞬时转速的波动性,提取曲线上的特征参数,得到各缸一致性和每隔6℃A结论基本一致,说明每隔30℃A提取稳态工况下瞬时转速也能准确判断各缸一致性,节约ECU的运算资源。

The transient speed of a crankshaft was used tocontrol the uniformity of each cylinder every 30 ℃A. Inexperiment, the transient speeds weremeasured under different loads at a steadystate condition of 1 600 r/min based on a DK4 A multi-cylinder diesel engine every 6 ℃A and 30 ℃A. It is shown that, when the transient speedwas acquisitioned at the interval of 30 ℃ A, the feature parameter can also be used to judge the uniformity of the cylinder. Therefore, the transient speed at the interval of 30 ℃A can be usedtoestimate the cylinder-by-cylinder uniformity so as to reduce the computation load of the electric control unit（ ECU）.