公开(公告)号：US20200271038A1

公开(公告)日：2020-08-27

申请号：US16646294

申请日：2018-09-06

Applicant: Scania CV AB

Inventor： Kurt KÄLLKVIST ,  Christer LUNDBERG

IPC: F01N11/00 ,  F01N3/20 ,  F01N13/00 ,  G01M15/10

Abstract: Disclosed is a method for diagnosing functionality of dosing units of a fluid dosing system comprising at least two dosing units, a tank unit for holding a fluid, and a pump unit for pressurizing the fluid for the dosing units. The method comprises determining a first hydraulic stiffness value on the basis of first pressure variations and determining a second hydraulic stiffness value on the basis of said second pressure variations. The first hydraulic stiffness value and second hydraulic stiffness value are compared. In a case where the first hydraulic stiffness value and second hydraulic stiffness value differ to a certain extent, concluding that malfunction of at least one of said dosing units is at hand, and in a case where the first hydraulic stiffness value and the second hydraulic stiffness value do not differ to said certain extent, concluding that the first and second dosing units function as intended.

公开(公告)号：US20200208558A1

公开(公告)日：2020-07-02

申请号：US16646605

申请日：2018-09-06

Applicant: Scania CV AB

Inventor： Kurt KÄLLKVIST ,  Emanuel REMMO ,  Joakim SOMMANSSON

IPC: F01N3/20

Abstract: Disclosed is a method for adapting control of a reducing agent dosing unit in a reducing agent provision system for emission control of a combustion engine. Characteristics relating to pressure variations associated with a dosing cycle are used for determining a first time period and a second time period. The time periods relate to a delay between activation of dosing and de-activation of dosing, respectively. The first time period and second time period are used for adapting operation of said reducing agent dosing unit.