Study On Data Acquisition And Typical Working Conditions Of Vehicle In Shijiazhuang

With the development of automobile industry,the number of cars in our country is increasing year by year.But some problems are becoming more and more significant such as energy,environment and road congestion.The evaluation of automobile energy consumption and exhaust emission is tested in the laboratory by the typical vehicle conditions.And typical operating conditions are not only the basis of automobile energy consumption and emission testing,but also the basis of the development,matching and evaluation of automotive products.The research of this paper is based on the project of "new energy vehicle detection in China" and mainly studies the collection of vehicle driving data and the construction of typical operation conditions for light vehicles in Shijiazhuang.The driving data of heavy vehicles are processed.And the eigenvalues of heavy vehicles are calculated and analyzed.Firstly,a portable vehicle data acquisition terminal and remote monitoring system are combined to realize the monitoring and management of remote test vehicles before the construction of the working condition.Secondly,the traffic data of 25 light vehicles and 10 heavy vehicles for 1 months were intercepted and atotal of 5372734 pice of data were collected from light vehicles,and 6931606 pice of data were collected from heavy vehicles.Thus,the light and heavy vehicle running database is established.The typical working conditions in Shijiazhuang are studied by using kinematic segments and characteristic parameter analysis:1.The software of data cutting and screening is developed by programming in C language.The software can calculate the eigenvalues of a large number of kinematic fragments.2.Based on the highest speed of fragments,the fragment database of four kinds of velocity intervals,low,medium,high and ultra high speed,was established respectively,It is determined that the working conditions of different speed ranges are 571 s,433s,428 s and 319 s,respectively considering the time length and time length distribution ratio of WLTC in European light vehicle driving condition;Finally,the typical working condition of light vehicle is established by calculating the fragment eigenvalues at different speeds and the ratio of the total length of each length segment to determine the optimal fragment.3.Working condition is verified by comparing the characteristic values of the working conditions and the segment eigenvalues,the overall working condition eigenvalues and the whole segment eigenvalues.The total duration of light duty vehicles in Shijiazhuang is 1704 seconds.The proportion of idle speed,uniform rate,acceleration ratio and deceleration ratio were 19.5%,13.9%,35.2% and 31.3%,respectively.The average speed was 35.1km/h and the fragment travel was 1.27 km.4.The whole eigenvalue of the kinematic segment of heavy vehicle is calculated by software.The average length of heavy vehicle segment is 54.3s and the ratio of idle speed,uniform speed,acceleration and deceleration is 29.7%,20.1%,26.4% and 23.8% respectively,and the average travel time was 0.23 km,with an average speed of 15.3 km/h.The whole feature is similar to the bus,the length of the segment is short,the proportion of idle speed is high,and the average speed is low.