中文摘要：

无级变速元件的承载能力一直是限制其应用领域的主要瓶颈，利用重新设计的功率分流机构和液压系统，减少无级变速元件载荷，速比变化范围大幅拓宽，提高低速扭矩表现，以实现500Nm以上的高扭矩传递能力，仿真结果表明改进的定速比传动机构、行星齿轮机构及其控制策略实现了操控性和平顺性要求。

英文摘要：

Power split CVT is a promising concept for automotive application in the future. Theoretically,it can offer a torque limit up to 500 Nm as well as total ratio spread between 6 and 7. The limitation for torque transfer capability can be raised,as the power flow through variator decreased. The system included variator and planetary gear set,which featured a power flow as following, the imput shaft transfer the power to sun gear and driving pulley. Thus a power split formed and Can realize variable possibilities.On the hydraulic concept,a double piston principle was applied for an advanced clamping system,which can provide sound privilege in fuel consumption. Control strategy was developed forthe CVT structure to achieve a more comfortable drivability and smoothness. Then computer simulation was carried out to show the result of optimization.