针对ELR测试循环的重型柴油机喷油策略研究

Injection Control Strategy of Heavy-duty Diesel Engine Based on ELR Test Cycle

ELR(European load response test)测试循环主要用于测试发动机在突加载荷时的炭烟排放情况,以重型柴油机为研究对象,探究了针对ELR测试循环的控制策略,并通过试验验证了其效果。结果表明,在动态过程中通过关闭VVT和EGR等方式可实现低的炭烟排放,而分段加油策略则有利于降低重型柴油机动态工况的烟度,先急后缓的加油策略则能达到最佳的炭烟排放效果。但动态过程中加油过急会造成转速超调量过大而无法满足ELR的要求,因此需要兼顾排放和转速超调的问题。

ELR test cycle is mainly used to test the soot emission of engine transient loading. For a heavy-duty diesel engine, the control strategy of ELR test cycle was discussed and its effect was verified by the experiment. The result shows that closing the VVT and EGR can achieve low soot emission. The multi-stage injection strategy is helpful to reduce the soot emission of transient conditions. First fast and after slow injection strategy can achieve the optimal soot emission. However, the too fast injection of dynamic process will lead to the large overshoot of engine speed so that the control cannot meet the legislation re- quirements, therefore, it＇s necessary to consider both speed overshoot and soot emission.