LPG发动机空燃比控制与流量特性分析

【作者】 蒋振宇；

【导师】 吴小平；

【作者基本信息】 南京理工大学 ， 车辆工程， 2004， 硕士

【摘要】 采用燃气发动机是解决能源危机和空气污染问题的有效措施。为了使燃气发动机在各种工况下获得最佳性能，达到提高功率、降低燃料消耗、减小排气污染的目的，必须采取发动机的闭环控制，因此空燃比的控制是发动机闭环控制的核心。 在汽油发动机闭环控制策略研究和氧传感器特性分析的基础上，结合LPG发动机的特性，提出了闭环控制策略。在LPG发动机台架实验中，分别采用了PI控制器和模糊控制器。实验结果表明，这两种控制器都达到了空燃比闭环控制的要求，模糊控制器控制精度更高、效果更好。 根据部分实验结果，用速度—密度法建立了理论空气流量和燃气流量的数学模型，得到了燃气供给MAP图，可供编制控制软件参考。更多还原

【Abstract】 The gaseous automotive engine was proved to be effective way to solve the problem of energy shortage and air pollution. The close loop is essential to engine, in order to make engine acquire optimum performance such as increasing power, falling resume of fuel etc. thus Air-Fuel-Ratio controlling is kernel of close-loop controller.Through studying closed -loop strategy of gasoline engine and analyzing characteristic of exhaust gas oxygen sensor, the paper gives the control strategies based on PI and Fuzzy. The experiment result manifest that both controllers operate well, Fuzzy controller is more precision and sensitive.The mathematical model for academic air and fuel gas flux based on experiments results is build up. MAP graphics of given fuel gas flux is put out, which is referenced by programming controlling software.更多还原