废气再循环阿特金森汽油机经济性优化算法

Economy Performance Optimization Algorithm of Exhaust Gas Recirculation Atkinson Gasoline Engine

摘要:

基于一维整机模型在3 000 r?min-1部分负荷工况下对Atkinson汽油机性能进行仿真分析.结果表明，在保持节气门位置、空燃比与点火提前角不变的情况下，随着废气再循环率提升或随着LIVC(late intake valve closing)增大，发动机的油耗均呈现增大趋势.为进一步优化Atkinson发动机燃油经济性，在节气门全开条件下搭建了GTpower与MATLAB联合仿真模型，通过改进的遗传算法，对废气再循环率、进气门晚关角、点火提前角、空燃比等参数进行优化迭代，并对历代种群进行了模糊聚类分析，得出了不同负荷工况点的油耗最优值及对应的控制参数.

关键词:汽油机; 阿特金森循环; 废气再循环; 进气门晚关; 优化方法

Abstract:

The performance of Atkinson gasoline engine was simulated and analyzed based on the 1D engine model at working condition of the part load of 3 000 r?min-1. The results show that with the increase of EGR rate or LIVC, the engine fuel consumption is increased in the case that the throttle position, airfuel ratio, and ignition timing keep unchanged. In order to improve the Atkinson engine fuel economy，the united simulation model of MATLAB and GTpower was set up in the wide open throttle working condition. The values of EGR rate, LIVC, ignition timing, and airfuel ratio were iteratively optimized by using a redesigned genetic algorithm. The fuzzy clustering method was adopted to analyze all the previous generations for obtaining the best fuel consumption and the corresponding control parameters at different load points.

Key words:gasoline engine; Atkinson cycle; exhaust gas recirculation (EGR); late intake valve closing (LIVC); optimization methods