中文摘要：

针对分时四驱汽车用分动器的优化研究问题，提出基于多种群遗传算法的分动器多目标优化设计方法。建立以最大爬坡度、燃油经济性以及齿轮重合度为目标的分动器多目标优化数学模型，基于多种群遗传算法进行优化设计，运用AVL-Cruise软件进行整车虚拟仿真模型，并对优化前后结果进行虚拟实验。结果表明：优化后车辆最大爬坡度降低2．78°，燃油消耗量降低12．52％，行星齿轮重合度提高8．62％；实验结果与优化结果相吻合，验证优化结果的正确性。

英文摘要：

Based on the detailed presentation of the structure and working principles of a time-sharing all-wheel- drive ear, we propose its transfer case＇s multiobjective optimization design method based on the multi-population genetic algorithms. In this paper, a transfer case optimization mathematical model was set up by using maximum climbable gradients, fuel economy and gear contact ratio, using MATLAB software for the optimization design. At the same time, the AVL Cruise software was used for the virtual simulation of the vehicle. The simulation results show that the optimized vehicle＇s maximum climbable gradient is 2.78 degrees lower, that its fuel consumption is 12.52% lower and that its planetary gear contact ratio increases by 8.62%. The experimental results are consistent with the optimization results and verify their correctness.