Investigation of a New Construction Method of Vehicle Driving Cycle

摘要

In order to overcome some ignored factors of traditional methods, a new method was applied for the research of driving cycles by the Markov stochastic process in the paper. The driving cycles were divided into 5 different states by maximum likelihood estimation. This associated driving segments with modal events which reflected acceleration variations and finely preserved speed variation characteristics of micro-time segments. On this basis the candidate cycles were required according to the transition probabilities of states and the representative driving cycle was constructed according to new evaluation criteria of 14 characteristic parameters. The actual application analysis of driving cycles was carried out with a example of typical roads in Hefei. The rationality of Markov method for the driving cycles was validated by the independent test. The results show that compared with the traditional method, the error of Markov method is smaller ,and has better similarity on modal events acceleration discrete distribution and is closer to the actual driving cycles of roads. That is to say, the new Markov method can be used to evaluate the emission levels of vehicles under real road condition and can be recommended as a test procedure used in China.