Systems and methods of an on-board NOx monitor reset test

• US 9,752,488 B2
• Filed: 10/27/2015
• Issued: 09/05/2017
• Est. Priority Date: 10/27/2015
• Status: Active Grant

• Current Assignee: Cummins Incorporated
• Original Assignee: Cummins Incorporated
• Inventors: Zambrano, Cristian Aldana, McGuire, Michael J., Shao, Josh Si
• Primary Examiner(s): Tran, Binh Q
• Application Number:
  US14/924,228
• Publication Number:
  US 20170114697A1
• Time in Patent Office: 679 Days
• Field of Search: 60274, 60276, 60277, 60286, 60295, 60297, 60301
• CPC Class Codes: F01N 11/007 the diagnostic devices measuring oxygen or air concentration downstream of the exhaust apparatus
• CPC Class Codes: F01N 2550/02 Catalytic activity of catalytic converters
• CPC Class Codes: F01N 2560/026 for measuring or detecting NOx
• CPC Class Codes: F01N 2900/0416 using the state of a sensor, e.g. of an exhaust gas sensor
• CPC Class Codes: F01N 2900/10 said parameters being related to the vehicle or its components
• CPC Class Codes: F01N 3/2066 Selective catalytic reduction [SCR]
• CPC Class Codes: F02D 2041/227 Limping Home, i.e. taking specific engine control measures at abnormal conditions
• CPC Class Codes: F02D 2200/501 Vehicle speed
• CPC Class Codes: F02D 41/0087 Selective cylinder activation, i.e. partial cylinder operation deceleration cut-off F02D41/123
• CPC Class Codes: F02D 41/022 in relation with the clutch status
• CPC Class Codes: F02D 41/0225 in relation with the gear ratio or shift lever position
• CPC Class Codes: F02D 41/024 to increase temperature of the exhaust gas treating apparatus
• CPC Class Codes: F02D 41/08 for idling F02D41/06, F02D41/16 take precedence
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

An apparatus includes a stationary conditions circuit structured to received information indicative of a stationary condition of a vehicle having an exhaust aftertreatment system; an engine circuit structured to cause an elevated operating mode in response to the detection of the stationary condition; and a nitrous oxide (NOx) monitor reset circuit. The NOx monitor reset circuit may be structured to: receive vehicle operation data indicative of an enable condition for a NOx monitor reset process; in response to the enable condition, receive NOx data indicative of a NOx amount exiting the exhaust aftertreatment system as part of the NOx monitor reset process; compare the NOx data to an estimated NOx amount; and in response to the comparison, selectively diagnose the exhaust aftertreatment system as one of a healthy and a degraded exhaust aftertreatment system.

Claims

1. An electronic controller, comprising:

a stationary conditions circuit structured to received information indicative of a stationary condition of a vehicle having an exhaust aftertreatment system;

an engine circuit coupled to the stationary conditions circuit, wherein the engine circuit is structured to cause an elevated operating mode in response to the detection of the stationary condition; and

a nitrous oxide (NOx) monitor reset circuit communicably coupled to the stationary conditions circuit and the engine circuit, wherein the NOx monitor reset circuit is structured to;

receive vehicle operation data indicative of an enable condition for a NOx monitor reset process;

in response to the enable condition, receive NOx data indicative of a measured NOx amount exiting the exhaust aftertreatment system as part of the NOx monitor reset process;

estimate a NOx amount exiting the exhaust aftertreatment system as part of the NOx monitor reset process;

compare the measured NOx amount to the estimated NOx amount; and

in response to the comparison, selectively diagnose the exhaust aftertreatment system as one of a healthy and a degraded exhaust aftertreatment system.

2. The electronic controller of claim 1, wherein the elevated operating mode includes causing an engine fluidly coupled to the exhaust aftertreatment system to operate in a cylinder cutout mode, the cylinder cutout mode including using less than a total number of cylinders of the engine.

3. The electronic controller of claim 1, wherein the enable condition includes an elevated temperature condition of a component in the exhaust aftertreatment system.

4. The electronic controller of claim 3, wherein the elevated temperature condition is based on a temperature of a selective catalytic reduction (SCR) catalyst being at or above a predefined threshold.

5. The electronic controller of claim 1, wherein the enable condition includes a flow rate of exhaust gas through the exhaust aftertreatment system.

6. The electronic controller of claim 1, wherein the elevated operating mode includes causing an engine fluidly coupled to the exhaust aftertreatment system to operate at a predefined engine speed range.

7. The electronic controller of claim 1, wherein the stationary condition is based on information indicating at least one of:

a clutch pedal being released, a transmission setting in one of a park setting and a neutral setting, a parking brake being released, a vehicle speed of zero miles-per-hour, a brake pedal being released, and an accelerator pedal being released.

8. The electronic controller of claim 1, wherein the NOx monitor reset circuit is structured to diagnose the aftertreatment system as healthy responsive to the comparison being at or within a predefined range.

9. The electronic controller of claim 1, wherein the NOx monitor reset circuit is structured to cause at least one of an activation of an indicator lamp, a maintaining activation of an indicator lamp, an activation of a derate condition for an engine, and a maintaining activation of a derate condition for the engine in response to diagnosing the aftertreatment system as degraded.

10. A method, comprising:

receiving, by a controller, vehicle operation data indicative of a stationary condition for a vehicle having an engine fluidly coupled to an exhaust aftertreatment system;

causing, by the controller, a speed of the engine to operate in an elevated condition;

determining, by the controller, an enable condition for a nitrous oxide (NOx) monitor reset process;

in response to the determined enable condition, receiving, by the controller, a measured system out NOx value;

estimating, by the controller, a system out NOx amount;

comparing, by the controller, the measured system out NOx value to the estimated system out NOx amount; and

in response to the comparison, selectively diagnosing, by the controller, the exhaust aftertreatment system as one of a healthy and a degraded exhaust aftertreatment system.

11. The method of claim 10, wherein the speed of the engine is between 1800 and 2150 revolutions-per-minute.

12. The method of claim 10, wherein the elevated condition further includes operating the engine in a cylinder cutout mode.

13. The method of claim 10, wherein the stationary condition is based on information indicating at least one of:

a clutch pedal being released, a transmission setting in one of a park setting and a neutral setting, a parking brake being released, a vehicle speed of zero miles-per-hour, a brake pedal being released, and an accelerator pedal being released.

14. The method of claim 10, wherein the enable condition includes a temperature condition of a component in the exhaust aftertreatment system.

15. The method of claim 14, wherein the temperature condition is based on a temperature of a selective catalytic reduction (SCR) catalyst being at or above a predefined threshold.

16. A system, comprising:

an engine;

an exhaust aftertreatment system in exhaust gas communication with the engine; and

a controller communicably and operatively coupled to the engine and the exhaust aftertreatment system, wherein the controller is structured to;

receive vehicle operation data indicative of a stationary condition for a vehicle having the engine and the exhaust aftertreatment system;

determine an enable condition is satisfied for the engine and exhaust aftertreatment system;

in response to the determined enable condition, receive system out nitrous oxide (NOx) data indicative of a measured NOx amount exiting the exhaust aftertreatment system;

estimate a NOx amount exiting the exhaust aftertreatment system;

compare the measured NOx amount to the estimated NOx amount; and

in response to the comparison, selectively diagnose the exhaust aftertreatment system as one of a healthy and a degraded exhaust aftertreatment system.

17. The system of claim 16, wherein the controller is included with the vehicle having the engine and the exhaust aftertreatment system.

18. The system of claim 16, wherein the controller is a service tool, wherein the service tool is a separate component from the vehicle.

19. The system of claim 16, wherein the stationary condition is based on information indicating at least one of:

a clutch pedal being released, a transmission setting in one of a park setting and a neutral setting, a parking brake being released, a vehicle speed of zero miles-per-hour, a brake pedal being released, and an accelerator pedal being released.

20. The system of claim 16, wherein in response to the determined enable condition, the controller is further structured to increase a speed of the engine to an elevated condition and cause operation of the engine in a cylinder cutout mode.