Research On Parameter Matching And Gear Shift Strategy Of Power Transmission System For Pure Electric Vehicle

In recent years,due to energy shortage and environmental pollution and other issues,the status of pure electric vehicles in the automotive industry is gradually rising because of its’clean energy.At present,the bottleneck of pure electric vehicle research is the problem of short driving range.On the basis of the existing level of research,through the parameter matching of power transmission system effectively makes the vehicle performance reaches a high level,prolong the mileage.In addition,this paper adopts the transmission mode of single motor driving two speed automatic mechanical transmissions,establishment of good schedules,meeting the vehicle’s power and economy standards.In this paper,choose a kind of pure electric vehicles as the research object,mainly on the following aspects of research:(1)Consulting the literatures at China and abroad,understanding the current technical level and development of pure electric vehicles,studied the key technologies of pure electric vehicles.(2)To determine the basic structure of pure electric vehicle in this paper,based on the vehicle dynamics theory,analyze the power and economy performance of pure electric vehicles,according to the vehicle parameters and performance indicators,matching the related parameters of the key components of the power transmission system.(3)The whole vehicle model is established in ADVISOR simulation software to verify the correctness of the Powertrain Parameters and shift strategy.(4)Different gear shift laws are established,including dynamic shift rule,economical shift rule and intelligent shift schedule formulated by fuzzy control principle,and the influence of the above gear shift rules on vehicle performance is compared.(5)The genetic algorithm with the vehicle model combination,with mileage as optimization objectives,to optimize the transmission ratio of the main reducer and two gear mechanical transmission,compared with the optimized transmission and transmission vehicle than before optimization than the mileage.