轻型柴油车还原性颗粒捕集器控制策略及排放试验研究

马标¹，张方戈¹，程晓章^2*，汪陈芳²

1.安徽江淮汽车股份有限公司技术中心，安徽 合肥  230601；2.合肥工业大学汽车与交通工程学院，安徽 合肥  230009

摘要：为使某轻型柴油车排放达到国六b排放标准，基于国六b轻型车排放标准对柴油机NO_x排放要求，制定柴油机选择性催化还原颗粒捕集器（selective catalytic reduction-coated diesel particulate filter，SDPF）后处理系统技术方案，建立结合前馈模型和反馈控制的SDPF控制策略，利用发动机台架试验对控制参数进行标定，并进行控制策略和排放测试验证。全球统一轻型车辆测试循环（world light vehicle test cycle，WLTC）工况转毂试验结果表明：SDPF化学反应模型的效率与基于NO_x传感器的NO_x转化效率具有良好的一致性，偏差小于10%，验证了控制策略的正确性和有效性；本方案的NO_x转化率达到96.1%，所有污染物排放均满足工程目标，该轻型柴油车排放满足国六b排放标准。

关键词：轻型柴油机；SDPF；后处理系统控制策略；WLTC试验

Experimental study on emission and control strategy of regenerative particulate filter for a light-duty diesel vehicle

MA Biao¹, ZHANG Fangge¹, CHENG Xiaozhang^2*, WANG Chenfang²

1.Technical Center, Anhui Jianghuai Automobile Co.,Ltd., Hefei 230601, China；

2.School of Automotive and Transportation Engineering, Hefei University of Technology, Hefei 230009, China

Abstract：In order to ensure that the emissions of a certain light-duty diesel vehicle meet the National 6b emission standards,based on the emission requirements for nitrogen oxides (NO_x) in light-duty diesel engines under the China 6b emission standards, a technical scheme for the selective catalytic reduction-coated diesel particulate filter(SDPF) after-treatment system is developed. An SDPF control strategy integrating a feedforward model and feedback control is established, and control parameters are calibrated using engine bench tests,and the control strategy and emission testing verification are conducted. The results of the chassis dynamometer WLTC tests show that the efficiency of the SDPF chemical reaction model is highly consistent with the NO_x conversion efficiency measured by NO_x sensors, with discrepancies less than 10%, confirming the correctness and effectiveness of the control strategy. The proposed scheme achieves a NO_x conversion rate of 96.1%, with all pollutant emissions meeting the engineering targets, successfully reaching the China 6b emission standard for a particular light-duty diesel vehicle.

Keywords: light diesel engine; SDPF; after-treatment control strategy; WLTC test