Automatic performance tuning for diesel exhaust fluid dosing unit

Patent metadata

Field	Value
Publication number	US-10260394-B2
Application number	US-201515570089-A
Country	US
Kind code	B2
Filing date	May 1, 2015
Priority date	May 1, 2015
Publication date	Apr 16, 2019
Grant date	Apr 16, 2019

Abstract

An auto-calibration controller configured to automatically tune a dosing unit of an aftertreatment system. The auto-calibration controller is configured to command the dosing unit to dose reductant at a first dosing command rate at a first input pressure value based on a dosing command value of a dosing command table. The auto-calibration controller is further configured to interpret a parameter indicative of an actual amount of dosed reductant by the dosing unit and compare the actual amount of dosed reductant to an expected amount of dosed reductant. The auto-calibration controller is further configured to update the dosing command value of the dosing command table of a control module of the aftertreatment system responsive to the comparison of the actual amount of dosed reductant to the expected amount of dosed reductant.

First claim

What is claimed is:

1. A system comprising:
an aftertreatment system including:
a dosing unit,
a reductant tank in fluid communication with the dosing unit, and
a control module operable to control dosing of reductant from the dosing unit based on a dosing command table;

a pressure sensor configured to detect an input pressure of reductant to the dosing unit from the reductant tank;
a second sensor configured to measure an actual amount of dosed reductant by the dosing unit; and
an auto-calibration controller configured to:
interpret a first parameter indicative of the input pressure of reductant to the dosing unit as substantially equal to a first input pressure value,
command the control module of the aftertreatment system to command the dosing unit to dose reductant at a first dosing command rate at the first input pressure value based on a dosing command value of the dosing command table,
interpret a second parameter indicative of the actual amount of dosed reductant by the dosing unit,
compare the interpreted second parameter indicative of the actual amount of dosed reductant to an expected amount of dosed reductant based on the first dosing command rate, and
update the dosing command value of the dosing command table of the control module of the aftertreatment system responsive to the comparison of the interpreted second parameter indicative of the actual amount of dosed reductant to the expected amount of dosed reductant.

2. The system of claim 1 , wherein the auto-calibration controller is further configured to:
command the control module of the aftertreatment system to command the dosing unit to dose reductant at a second dosing command rate at the first input pressure value based on a second dosing command value of the dosing command table,
interpret a third parameter indicative of a second actual amount of dosed reductant by the dosing unit,
compare the interpreted second parameter indicative of the second actual amount of dosed reductant to a second expected amount of dosed reductant based on the second dosing command rate, and
update the second dosing command value of the dosing command table of the control module of the aftertreatment system responsive to the comparison of the interpreted third parameter indicative of the second actual amount of dosed reductant to the second expected amount of dosed reductant.

3. The system of claim 1 further comprising:
an outside pressure supply in fluid communication with the reductant tank;
wherein the auto-calibration controller is configured to selectively control a pressure of air supplied to the reductant tank from the outside pressure supply to control the input pressure of reductant to the dosing unit.

4. The system of claim 1 , wherein the auto-calibration controller is configured to update the dosing command value responsive to a difference between the interpreted second parameter indicative of the actual amount of dosed reductant relative and the expected amount of dosed reductant exceeding a predetermined error threshold.

5. The system of claim 1 , wherein the auto-calibration controller is further configured to:
command the control module of the aftertreatment system to command the dosing unit to dose reductant at the first dosing command rate at the first input pressure value based on the updated dosing command value.

6. The system of claim 1 , wherein commanding the dosing unit to dose reductant at the first dosing command rate based on the dosing command value of the dosing command table comprises dosing reductant at the first dosing command rate based on the dosing command value for a predetermined period of time.

7. The system of claim 1 , wherein commanding the dosing unit to dose reductant at the first dosing command rate based on the dosing command value of the dosing command table comprises dosing reductant at the first dosing command rate based on the dosing command value for a predetermined volume.

8. The system of claim 1 , wherein the second sensor is a weight scale.

9. The system of claim 8 , wherein the second sensor measures the actual amount of dosed reductant by the dosing unit based on a weight of the reductant tank.

10. The system of claim 8 , wherein the second sensor measures the actual amount of dosed reductant by the dosing unit based on a weight of a receiving tank into which reductant from the dosing unit is dosed.

11. An auto-calibration controller for automatically tuning a dosing module of an aftertreatment system, the aftertreatment system including the dosing module, a reductant tank in fluid communication with the dosing unit, and a control module operable to control dosing of reductant from the dosing unit based on a dosing command table, the auto-calibration controller comprising:
a calibration module configured to:
interpret a first parameter indicative of an input pressure of reductant to the dosing unit as substantially equal to an input pressure value of the dosing command table,
command the dosing unit to dose reductant at a dosing command rate at the input pressure value based on a dosing command value of the dosing command table,
interpret a second parameter indicative of an actual amount of dosed reductant by the dosing unit,
compare the interpreted second parameter indicative of an actual amount of dosed reductant to an expected amount of dosed reductant based on the dosing command rate, and
update the dosing command value of the dosing command table of the control module of the aftertreatment system responsive to the comparison of the interpreted second parameter indicative of the actual amount of dosed reductant to the expected amount of dosed reductant.

12. The auto-calibration controller of claim 11 , wherein the calibration module is further configured to:
command the dosing unit to dose reductant at the dosing command rate at the input pressure value based on the updated dosing command value.

13. The auto-calibration controller of claim 12 , wherein actual amount of dosed reductant by the dosing unit is based on an output of a weight sensor measuring a weight of one of the reductant tank or a receiving tank into which reductant from the dosing unit is dosed.

14. The auto-calibration controller of claim 13 , wherein the calibration module is further configured to:
selectively control a pressure of air supplied to the reductant tank from an outside pressure supply to control an input pressure of reductant to the dosing unit.

15. The auto-calibration controller of claim 14 , wherein the calibration module is configured to update the dosing command value responsive to a difference between the interpreted second parameter indicative of the actual amount of dosed reductant relative and the expected amount of dosed reductant exceeding a predetermined error threshold.

16. The auto-calibration controller of claim 15 , wherein commanding the dosing unit to dose reductant at the dosing command rate based on the dosing command value of the dosing command table comprises one of dosing reductant at the dosing command rate based on the dosing command value for a predetermined period of time or a predetermined volume.

17. A system comprising:
an aftertreatment system including:
a dosing unit,
a reductant tank in fluid communication with the dosing unit, and
a control module operable to control dosing of reductant from the dosing unit based on a dosing command table; and

an auto-calibration controller configured to:
interpret a first parameter indicative of an input pressure of reductant to the dosing unit as substantially equal to an inpu

Assignees

• Cummins Emission Solutions Inc

Inventors

• Hudson Patrick C
• Khaled Nassim

Classifications

• F01N2610/148

  Arrangement of sensors · CPC title

• F01N9/00

  Electrical control of exhaust gas treating apparatus (monitoring or diagnostic devices for exhaust-gas treatment apparatus F01N11/00; conjoint electrical control of two or more combustion engine functions F02D43/00) · CPC title

• F01N2900/1814

  Tank level · CPC title

• F01N3/208 Primary

  Control of selective catalytic reduction [SCR], e.g. by adjusting the dosing of reducing agent · CPC title

• F01N2610/02

  the substance being ammonia or urea · CPC title