Design And Simulated Analysis Of Transmission Ratio Of Pure Electric Vehicle With Two-gearbox Based On ADVISOR

Automobile have had a great influence on people's lifestyle and production since it was invented,and at present it becomes one of the mean vehicles in daily life.Booming development of automobile brings great convenience as well as tremendous harm to people's health and living environment,so it is an efficient approach to research new energy vehicle technology and vigorously support and develops battery driven Pure Electric Vehicles(PEV)in order to reduce the harm,meanwhile these new technique points a new direction for auto industry.PEV has the advantages of zero emission,fast acceleration and low noise,a car fitted A transmission with a fixed speed ratio can basically meet the operation requirements when seasonable logical control was adopted,and at the same time,it proposed a higher technical requirements in Motor and battery which always restrict the development of PEV.PEV E6 designed and made in BYD Group was taken as an example to study auto transmission ratio,the fixed speed-ratio transmission was redesigned as two speed transmission with two transmission ratios so that the performance of the whole car will be improved.By using ADVISOR software,the feasibility and validity of PEV with two speed transmissions were studied.The main research contents are as following:(1)Basic structure and work principle of E6 are briefly analyzed;its transmission type and its advantages and disadvantages are also studied.Based on the requirement of power and economy performance,the vehicle,power system and transmitting system and its main parameters of E6 were determined.(2)Transmission ratio was recalculated through knowledge of automobile dynamics,the results shows that one gear transmission ratio is 2.31,two gears transmission ratio is 1.58,while transmission ratio of main reducer is 3.85.(3)Vehicle model,motor model,power cell model,main reducer model,transmission model and wheel axle model were all set up based on ADVISOR,the dynamic performance and fuel economy of the model were simulated and analyzed.(4)The simulated and analyzed results imply two speed transmissions redesigned in this paper can fully meet the needs of dynamic performance and fuel economy.These results also indicate that the maximum speed increased by 10%,Maximum climbing gradient increased by 19%,100 km acceleration time increased by 3.2%,Overall energy efficiency increased by42%,Battery power consumption decreased by1.9%.