道路坡度对重型车PEMS测试影响试验研究

郑志强¹，潘晓¹，贾建成²，田浩宇¹，江宏昊¹，钟祥麟^3*

1.潍柴动力股份有限公司，山东 潍坊  261061；2.中国重型汽车集团有限公司，山东 济南  250100；

3.中汽研汽车检验中心（天津）有限公司，天津  300300

摘要：通过实际道路测试和试验室底盘测功机复现试验的方法，研究道路坡度对重型柴油车实际道路测试结果的影响。试验结果表明：道路坡度直接影响发动机负载状态，从而影响燃油消耗和污染物排放；比油耗和CO₂比排放与车辆是否处于坡路行驶无直接关联，基于里程的油耗评估无法全面反映车辆的能效水平；NO_x排放受多种因素影响，下坡可能因排温下降而降低选择性催化还原系统效率，导致排放升高，也可能因发动机功耗降低而减少NO_x排放。道路坡度是评估重型车辆实际道路排放不可忽视的重要因素。

关键词：坡度；重型车；便携式排放测试系统；油耗；NO_x排放

Experimental study on the impact of road grade for a heavy-duty vehicle PEMS test

ZHENG Zhiqiang¹, PAN Xiao¹, JIA Jiancheng², TIAN Haoyu¹, JIANG Honghao¹, ZHONG Xianglin^3*

1.Weichai Power Co., Ltd., Weifang 261061, China;

2.China National Heavy Duty Truck Group Co., Ltd., Jinan 250100, China;

3.CATARC Automotive Test Center (Tianjin) Co., Ltd., Tianjin 300300, China

Abstract：The effect of road slope is studied on PEMS testing of heavy-duty diesel vehicles through actual road testing and laboratory chassis dynamometer replication tests. The results show that changes in road slope directly affect the engine load state, thereby affecting fuel consumption and pollutant emissions. Although the mileage fuel consumption increases on uphill and decreases on downhill, the specific fuel consumption and CO₂ emissions are not directly related to whether the vehicle is driving on a slope, and mileage based fuel consumption assessment cannot fully reflect the vehicle′s energy efficiency level. NO_x emissions are influenced by various factors. Downhills may result in a decrease in SCR efficiency due to a decrease in exhaust temperature, leading to an increase in emissions, or a decrease in NO_x emissions due to a decrease in engine power consumption. In short, road slope is an important factor that cannot be ignored in evaluating the actual road emissions of heavy vehicles.

Keywords: road grade; heavy-duty vehicle; PEMS; fuel consumption; NO_x emission