公开(公告)号：US20160252036A1

公开(公告)日：2016-09-01

申请号：US15150751

申请日：2016-05-10

Applicant: Caterpillar Inc.

Inventor： Hua Xu ,  Arvind Sivasubramanian ,  Shaun D. Fogle ,  David J. Lin

IPC: F02D41/24 ,  F02D41/14

CPC classification number: F02D41/1475 ,  F02D41/1463 ,  F02D2041/281 ,  F02D2041/286

Abstract: The disclosure provides a method to operate an engine system. The method begins by determination of a current NOx value. If the current NOx value is greater than a first predetermined NOx target, an air-fuel ratio (AFR) set-point is adjusted by a first predetermined value in towards a rich AFR. Upon detection of the current NOx value below the first predetermined NOx target, a first average of NOx values for a first predetermined time is determined. The AFR set-point is adjusted by a second predetermined value and a second average of NOx values for a second predetermined time is determined. A delta NOx value is determined as a difference between the first average and the second average and compared with a second predetermined NOx target. The AFR set-point is determined when the delta NOx value is below the second predetermined NOx target.

Abstract translation: 本公开提供了一种操作发动机系统的方法。 该方法通过确定当前的NOx值开始。 如果当前的NOx值大于第一规定的NOx目标，则将空燃比（AFR）设定点向着浓AFR调整第一预定值。 当检测到当前NOx值低于第一预定NOx目标值时，确定第一预定时间的NOx值的第一平均值。 AFR设定点被调整第二预定值，并确定第二预定时间的NOx值的第二平均值。 Δδ值被确定为第一平均值和第二平均值之差，并与第二预定NOx目标进行比较。 当ΔNOX值低于第二预定NOx靶时，确定AFR设定点。