公开(公告)号：US20130318949A1

公开(公告)日：2013-12-05

申请号：US13905565

申请日：2013-05-30

Applicant: Honda Motor Co., Ltd.

Inventor： Hideki MATSUNAGA ,  Yuji YASUI ,  Naohiro SATO ,  Masafumi SAKOTA ,  Eiji HASHIMOTO

IPC: F01N3/10

CPC classification number: F01N3/10 ,  F01N3/035 ,  F01N3/0814 ,  F01N3/0842 ,  F01N3/101 ,  F01N3/2066 ,  F01N13/009 ,  F02D41/0275 ,  F02D41/1465 ,  F02D2200/0806 ,  Y02A50/2345 ,  Y02T10/22

Abstract: An exhaust gas purifying system includes: a SCR catalyst which has a function of reducing NOx and absorbing NO2; an upstream catalyst which is provided at the upstream side of the SCR catalyst and has a three-way purification function; and an air-fuel ratio controller which controls the air-fuel ratio of the air-fuel mixture. The controller calculates the NO2 storage amount of the SCR catalyst (S2), calculates a value of the NOx correlation parameter that increases in response to the NOx discharge amount (S4), sets the stoichiometry determination threshold value to a small value as the NO2 storage amount increases (S5), and changes the operation mode of the engine to the stoichiometry operation mode in which the air-fuel ratio is controlled to stoichiometry when the value of the NOx correlation parameter is larger than the stoichiometry determination threshold value (S6, S9).

Abstract translation: 废气净化系统包括：SCR催化剂，其具有还原NOx和吸收NO 2的功能; 上游催化剂，其设置在SCR催化剂的上游侧并具有三元纯化功能; 以及控制所述空气燃料混合物的空燃比的空燃比控制器。 控制器计算SCR催化剂的NO 2储存量（S2），计算响应于NOx排放量而增加的NOx相关参数的值（S4），将化学计量确定阈值设定为较小的值作为NO 2储存 （S5），并且当NOx相关参数的值大于化学计量确定阈值时，将发动机的操作模式改变为将空燃比控制为化学计量的化学计量操作模式（S6，S9 ）。