基于CVT变速器的燃油经济性优化潜力研究

为了获得某CVT车型速比参数优化对燃油经济性直接改善的潜力,首先,获得了NEDC循环中的发动机运行工况分布特征,市区循环中绝大部分工况都处于最佳燃油经济性曲线以下。随后,根据速比控制方法评估了可以优化的区域,其中市区循环中7%的工况可以优化,市郊循环中部分工况(车速达到70 km/h和100 km/h时),由于速比限值限制无法优化调整。根据仿真结果,仅调整CVT变速器的速比参数,包括调整部分工况至最佳燃油经济性曲线上,或在全部区域内优化,或放宽CVT变速器的速比范围,最大节油潜力的直接贡献达到3. 12%。

Study on Optimization Potential of Fuel Economy based on CVT

In order to obtain the potential of the speed ratio parameter optimization of a CVT vehicle on the direct improvement of fuel economy,the first step is to obtain the distribution characteristic of engine operating condition from test data in the NEDC cycle,most of the operating conditions are located in the urban cycle are below the optimal operation curve(OOC). Then,the area that can be optimized is evaluated according to the speed ratio control method,there is 7% of the engine operating condition in the urban cycle can be optimized,in some working conditions in the suburban cycle(when the vehicle speed is up to 70 km/h and100 km/h),it cannot be optimized and adjusted due to the speed ratio limited value of the CVT. According to the simulation results,only the speed ratio parameters of CVT transmission are adjusted,including adjusting some operation conditions to the optimal fuel economy curve,or optimizing in all area,or enlarging the speed ratio range of CVT transmission,and the direct contribution of the maximum fuel saving potential reaches 3.12%.