Optimum Design And Performance Analysis Of Electric Wheel Side Reducer

With a large number of emergence development of electrical vehicles, people gradually began to focus attention on the study of electric vehicle driving system. The technology of the wheel hub motor has been paid for much attention which characteristics is to integrate power, drive and brake device into internal rim forming the electric wheel. Electric wheel drive is depend on the drive system of the hub reduction gear by changing the input torque and revolving speed for achieving the goal of slowdown the speed and increase the torsion, and then transmitted to the wheels, so that the wheels under the adhesive force on the ground producing larger driving force.In China, with the emergence of small electric vehicles, the installation space of the hub reduction gear is limited which request to reduce its structure size, in the same time, the requirement of the comfort for it is becoming more and more high. Therefore, the hub reduction gear needs to be more compact structure and stable transmission for meet the requirements of the new product.Wheel-side reducer is the object of the research. Through the genetic algorithm theory, its transmission system was optimized, which satisfying the design requirements of volume reducing and weight saving. The new model was determined by the optimized parameters, and realizing the modeling, assembling and interference checking of the product by using the three-dimensional modeling software. The rationality of the new model was examined through its performance analysis. Because of the drive stability directly affects the comfort and the noise pollution, therefore, gear teeth was profile modification by Romax software, getting more uniform load distribution, more stationary driving and less environmental pollution, providing necessary basis for later production. Researches focus on the followings:(1) According the theory of genetic algorithm, through the Matlab software, using minimum volume as a mathematical model of the objective function,eventually produce a new model of transmission system. Comparing the optimization of parameters, It show that achieved the goal of the optimization.(2) Based on the optimization of the model, using 3D modeling software Pro/E to achieve the virtual modeling、assembly and the inspection about interference, Prove that there is no interference. Meshing force curve compliance requirements of actual situation.(3) The sun gear and planetary are the basic parts of reduction system, the strength of the planet carrier plays a vital role in the whole system, test the strength of the planet carrier is essential, therefore, through the planet carrier strength meet the requirements of statics analysis, prove its rationality. the contact stress is one of the main factors of the failure mode, according the analysis of FEA to prove it satisfy the strength requirement. Compare the modal analysis of the vibration frequencies and its calculation meshing frequency of the planetary gear train, it will not be destroyed.(4) Using of the tooth surface micro optimization module of the Romax for analysis and modification of sun gear and the planets wheel,after the profile modification,the maximum load is reduced, the load distribution has been improved, and reduce the transmission error. it not only increase the bearing capacity and life of the gear. But also achieve the expected goal of the vibration and noise reduction.