Research Of Construction Of The Light-duty Vehicles Driving Cylce

Because of the increase of car ownership in recent years, the urban traffic pressureincreases and the air pollution is increasingly serious in cities. Driving cycle is the basis formeasure vehicles pollutant emissions and fuel consumption, also is the basis for vehiclesrelated laws and regulations on energy saving and emission reduction. At present, thedomestic uses the new European driving cycle. There are many differences from the urbanroad planning, traffic conditions and driving habits, so the new European driving cycle isdifficult to accurately reflect on domestic traffic conditions, and various types of test whichare based on driving cycle will not be accurate. Researching the build of domestic drivingcycle is a great significance.This paper selectes Tianjin light-duty vehicles to study and developed a comprehensiveprogram of test data acquisition. The driver’s age, driving experience and gender factors,temperature, seasonal factors are added to the design of the collection program. The70daystest datas are selected to data preprocess, and it gets high and low peak periods databases.Short trip is regarded as the smallest unit to built driving cycle. The11characteristicparameters instead of short trip are used to principal component analysis and it gets the firstfour principal components. Then the scores of principal components are used to clusteranalysis, and the high and low peak periods databases are again divided into two categories.The cumulative frequency of short trip duration is used to select some short trips in the fourdatabases and the chi-square test is used to select the optimal driving cycle, which works outthe diversity problem caused by random selection in the past.This paper gets high and lowpeak periods driving cycles. It calculates the error between driving cycle and test data fromthe overall characteristic parameters, velocity range, acceleration range, speed andacceleration joint distribution, which confirmes the method of bulid driving cycle isreasonablePreprocessing test data, dividing short stroke, calculating the characteristic parameters,calculating the speed and acceleration joint distribution, calculating the cumulative frequencyof duration, calculating the chi-square statistic come true by programming in MATLABsoftware.