The Design And Research On The Automatic Transmission Of Electric Vehicle

As the shortage of petroleum resource all the world,and also see the Enhanced Greenhouse Effect and the emission of poisonous gasses, the environmental problems becomes more and more serious, the research and development of electric vehicle has already begun in every country. Along with the development of science technology, people have higher request to automobile.and because the manual transmission has some disadvantages in the practical applications,it will be an inevitable trend that the manual transmission will be replaced by automatic transmission.The paper carries on the design and research of an four-speed automatic transmission based on a 5-speed manual transmission that are mainly used for mini cars. That requires fairly good dynamics performance and economic performance without changing its basic design parameters.The article researches and analyzes the automatic transmission according to the given parameters and the performance requirements of complete vehicle. second, the choice of drive motor type is achieved in this article in order to improve the electric vehicle's overall performance. Furthermore,the paper calculated the motor's performance parameters and its transmission parts' relative parameters,attained four gears of the automatic transmission and designed its transmission ratio appropriately.Then it mainly designed the transmission parts of the transmission, selected related parts and calculated its parameters, calculated and checked some important components on the basic of theory.And then 3-D models of the transmission parts are set up by using a 3D modeling software PRO/E. In the process of making model, the parametric modeling method is used for helical gears. It can construct an actual model of cylindrical gear by defining a range of parameters,and can get other gear models conveniently by modifying the characteristic parameters. So it can help to avoid refounding model and largely improve the efficiency of design by this method. After establishing corresponding solid model, the three-dimensional model is imported into the finite element analysis software ANSYS. Because each axle and the gear stand the largest loading when the car is running at the fir st gear,the paper analyses the situation.And established finite element analysis model by selecting element types, defining material properties, meshing and so on.Then apply ANSYS to researche and analyze related parts and compon ents in statics to get the stress and strain condition.By analyzing the the stati-c characteristics, the simulation result is evaluated ulteriorly.So the design an-d research provide necessary theories foundation and design methods for desig ning automatic transmission for electric vehicle.