燃气增程式混动车加载策略对NO_x排放影响  

Experimental Study into the Influence of Engine Loading Strategy on NO_(x) Emissions for a Range-Extended Hybrid Natural Gas Vehicle

作　　者：朱赞[1] 邓远海[1] 官维 Zhu Zan;Deng Yuanhai;Guan Wei(Guangxi Yuchai Machinery Company Limited,Yulin 537000,China)

机构地区：[1]广西玉柴机器股份有限公司,广西玉林537000

出　　处：《内燃机学报》2021年第5期439-444,共6页Transactions of Csice

基　　金：国家重点基础研究发展计划资助项目(2007CB210004);吉林大学“985”工程资助项目(20080209)。

摘　　要：由于京Ⅵ法规的特殊性,典型增程式混合动力车整车排放可以达标国Ⅵ法规要求,但无法满足京Ⅵ法规要求.针对该问题,在一台4缸4.5 L排量的增程式混合动力天然气车专用发动机上,按照中国典型城市公交循环(CCBC循环)工况开展了不同加载策略对瞬时NO_x排放的影响,研究分析了典型增程式混合动力天然气车发动机启动阶段的工作特征,以及启动阶段加载时间和加载路径对整车排放的影响.研究表明:在常规加载路径(即发动机转速和负荷线性增长)情况下,延长加载时间3 s至40 s能有效降低NO_x排放,把整车瞬时NO_(x)排放30 s平均值从786×10^(-6)减少至504×10^(-6),能够满足京Ⅵ法规但相对法规限值的裕度不大.然而通过在启动阶段改变加载路径策略的研究发现,使用先在小负荷工况提升发动机转速至目标值,之后保持发动机转速不变提升发动机负荷至目标值的加载路径,可以将整车瞬时NO_x排放30 s平均值进一步降低至271×10^(-6),满足京Ⅵ整车法规要求的同时保证了足够的裕度.In general,emissions of a typical range-extended hybrid vehicle can meet the requirements of ChinaⅥregulations,but fail to meet the requirements of BeijingⅥregulations due to its particular specificity.In respond to this issue,the impact of different loading strategy on the transient NOx emissions was performed on a 4-cylinder range-extended hybrid natural gas(NG)vehicle with an engine displacement of 4.5 liters,on the basis of typical Chinese city bus cycle(CCBC).Operation characteristics of the typical range-extended hybrid NG vehicle were analyzed and the impact of engine loading strategy on NO_(x) emissions was investigated during the start-up phase.Results show that in the case of the typical loading strategy with linear increase of engine speed and load,extending the loading time from 3 s to 40s reduces the 30 s-averaged transient NOx emissions from 786×10^(-6) to 504×10^(-6),which can meet BeijingⅥNO_(x) limit with a small margin.Results also reveals that the 30 s-averaged transient NO_(x) emissions can be effectively reduced from 504×10^(-6) to 271×10^(-6) if a new loading path was used,in which the engine speed is first increased to a target value in a small engine load condition and then the engine load is increased to its target value at the condition of constant engine speed.This low NOx level can be compliance to the BeijingⅥregulations with a sufficient margin.

关 键 词：增程式混合动力燃气车 加载策略 瞬时NO_x排放 

分 类 号：TK437[动力工程及工程热物理—动力机械及工程]