Study On Parameters Of Power Train For Urban Bus Based On Driving Cycles

Parameters of power train have great affection on the performance of power and fuel economy according to driving cycles. The tests and methods on driving cycle are studied in this paper. The parameters of power train for urban bus are optimized based on driving cycles.A method of driving cycle construction based on performance value (PV) is developed for urban bus. Driving condition data is collected on the representative routes which are selected between the major residential areas and commercial or industrial areas according to the traffic flow. The micro-trip is defined as a trip between two bus stops. A driving cycle is then constructed with the randomly selected micro-trips according to the proportion of the driving condition. The representative urban bus driving cycle is selected by the deviation of the parameter mean value. The improved method of urban bus driving cycle construction and the synthesized Dalian urban bus driving cycle are both verified with the case study of urban bus in Dalian.A method of drive train parameter optimization design based on design of experiment (DOE) is developed. The parameters are analyzed for the match of power train according to the curves of power and fuel economy performance. The parameters of power train are also optimized with the restraints of power performance for the objective of minimum fuel consumption in driving cycles. The fuel consumption is reduced with the normal power performance through the optimization of power train. The method of orthogonal design is applied in the DOE, and the experiments are simulated. The results are analyzed with the analysis of regression to study the effect of the drive and fuel economy performance by the factor of drive train parameters. The parameters of drive train are also designed with the method of optimization to provide the reference of the design of drive train.An improved methodology of matching and evaluation for automotive power transmission is developed with the integer performance factor based on the weighted sum of power effect factor and fuel economy effect factor. The evaluation of the power transmission matching of a bus with the improved methodology shows that the methodology is practiced based on the result of the simulation calculation and test verify.