工况驾驶规范性及客观评价指标相关性的试验研究

Research on Standardization of Cycle Driving and Correlation Analysis of Driving Evaluation Indexes

通过引入驾驶评价指标和制动压力的控制及其要求规范了驾驶行为,为提高测试的准确性以及可重复性提供了保障。利用8名具有多年底盘测功机驾驶经验的驾驶员及两台轻型汽油车,在底盘测功机上开展了大量的新欧洲驾驶循环测试(New European Driving Cycle,NEDC)和全球轻型车统一循环测试(Worldwide Harmonized Light Vehicles Test Cycle,WLTC),并以10 Hz为采样频率连续记录数据进行综合计算,得到驾驶评价指标结果。通过相关性分析,认定驾驶风格对油门扰动性的影响在NEDC工况下比在WLTC工况下的更大,主因是驾驶员在稳定工况下拥有更多的自由度。对于NEDC工况,可以通过设定IWR及EER限值来实现规范驾驶;对于WLTC工况,可以通过设定IWR和RMSSE限值来实现规范驾驶。此外,通过限制工况驾驶过程中的最大制动压力还为规范驾驶提供了有效途径。不仅为降低不同驾驶员对燃料消耗量测试的影响提供了参考,在我国汽车领域实现“双碳”目标的背景下,也为乘用车碳排放大数据采集的准确性提供了借鉴。

To assist OEMs in reasonably,accurately determining the declared value of fuel consumption for both type approval and COP,thereby gaining more CAFC benefits,it is essential to standardize driving behavior,which is a key factor influencing fuel consumption tests.This can be achieved by introducing driving evaluation indices and brake pressure.Moreover,setting specified requirements ensures the accurate and repeatable measurement results.Eight drivers,each with several years of driving experience in emission dyno testing,along with two light-duty gasoline vehicles,were employed to conduct a large number of emission tests on the chassis dynamometer under NEDC and WLTC conditions.The driving evaluation indexes were calculated based on the data sampled at a 10 Hz frequency.Through statistical analysis,the influence of driving style on vehicle running smoothness is greater in NEDC compared with WLTC.This is attributed to the greater degree of freedom given to the driver under the stable conditions in NEDC.For the WLTC,setting IWR and RMSSE limits based on the empirical values ensures that the cycle is performed under qualified driving.Besides,regulating the maximum brake pressure during the cycle is an effective measure.This paper offers insights into minimizing the variance caused by different drivers in fuel consumption tests and it provides a method to accurately calculate carbon emissions,both of which can contribute to the progress in achieving China's Dual-Carbon goals in automobile industry.