基于车联网数据的商用车行驶工况构建方法

A Method for Constructing Commercial Vehicle Driving Cycle Based on IOV Data

针对经典驾驶循环工况曲线无法真实反映国内商用车运行工况特征,导致整车动力系统与实际运行工况不符,产生动力不足及油耗高等问题,以石家庄至太原的一条重型商用车运输路线为研究对象,基于车联网获取了车辆行驶数据。采用平均速度法将建立的片段数据库进一步划分为低、中、高速3类,分别对这3类进行了2次片段切割并计算了各类片段特征参数值。利用主成分分析法对各短行程片段的特征参数进行了降维,选取能够代表主要信息的主成分,利用聚类分析法将各短行程片段进行了分类处理。根据每一类片段所占时间比例确认各类中需要选取的片段数,选择相关系数较高的片段,构建了一条基于真实场景的商用车行驶循环工况曲线。结果表明:通过与NEDC和FTP-75等工况的对比分析发现,匀速时间比例、怠速时间比例及平均速度存在较大差异,说明车辆行驶环境和车型对车辆的行驶工况影响较大;石家庄至太原的商用车行驶工况相较国内外典型工况有自己独特的特征;与实际采集数据特征参数值对比,所研究工况误差较小,验证了该工况更符合实际道路行驶工况及该工况构建方法的可行性,对特定地区、特定路线重型商用车行驶工况的开发具有重要意义。

In view of the fact that the characteristics of domestic commercial vehicle driving cycle cannot be truly reflected by the classical driving cycle curve,that leads to the inconsistency between the vehicle power system and actual driving cycle,and results in insufficient power and high fuel consumption,etc,taking a heavy-duty commercial vehicle transport route from Shijiazhuang to Taiyuan as the study object,the vehicle driving data are obtained based on the IOV.The established fragment database is further divided into low,medium and high speeds by using the average speed method,the 2nd fragment cutting is carried out for these categories respectively,and the characteristic parameter values of all categories of fragments are calculated.The dimension reduction of the characteristic parameters of each short trip fragment is processed by using principal component analysis,the principal component that can represent the main information is selected,and each short trip fragment are classified by using clustering analysis.According to the time proportion of each fragment category,the number of fragments that need to be selected in each category is confirmed,the fragments with high correlation coefficient are selected,and a commercial vehicle driving cycle curve based on real scene is established.The result shows that(1)by comparing with NEDC,FTP-75 and other driving cycles,it is found that there are great differences in uniform time proportion,idle time proportion and average speed,illustrates the great influences of driving environment and vehicle type on driving cycles;(2)the driving cycle of commercial vehicles from Shijiazhuang to Taiyuan has its own unique characteristics compared with the typical driving cycles in China and abroad;(3)compared with the characteristic parameter values of actual collected data,the errors of the studied driving cycle are small,which verified that the driving cycle is more in line with the actual road driving cycle and the feasibility of the driving cycle construction method,and it has great significance to the development of heavy-duty commercial vehicles driving cycles in specific regions and routes.