Method and system for charge air system valve diagnosis

Patent metadata

Field	Value
Publication number	US-9422896-B2
Application number	US-201313752446-A
Country	US
Kind code	B2
Filing date	Jan 29, 2013
Priority date	Jan 29, 2013
Publication date	Aug 23, 2016
Grant date	Aug 23, 2016

Abstract

Various methods and systems are provided for diagnosing the position and function of a valve in an engine system. In one embodiment, a method for an engine comprises determining a position of a valve in an engine system based on a turbine speed response upon commanded actuation of the valve.

First claim

The invention claimed is:

1. A method, comprising:
via a controller of an engine system:
communicating information relating to a first valve in the engine system based at least in part on a turbine speed response to actuation of the first valve while maintaining a second valve in one of a fully open and fully closed position during actuation of the first valve, where the first valve and the second valve are both positioned in a flow of gas including at least some exhaust gas, wherein the information comprises a position of the first valve that is determined based at least in part on the turbine speed response to actuation of the first valve and the fully open or fully closed position of the second valve and wherein the actuation of the first valve includes a command generated in response to a diagnostic cycle, where the diagnostic cycle is triggered if the first valve has not been actuated for a set amount of time.

2. The method of claim 1 , wherein the actuation of the first valve includes a command to increase or decrease an opening size of an aperture defined at least in part by the first valve.

3. The method of claim 1 , further comprising determining an expected change in turbine speed based on the actuation of the first valve and the fully open or fully closed position of the second valve.

4. The method of claim 1 , wherein the first valve is a first exhaust gas recirculation valve disposed in an exhaust gas recirculation system of the engine system and the second valve is a second exhaust gas recirculation valve disposed in the exhaust gas recirculation system.

5. The method of claim 4 , further comprising maintaining a turbine bypass valve disposed in a bypass around a turbine, the turbine disposed in an exhaust passage, in one of a fully open and fully closed position during actuation of the first valve and wherein the position of the first valve is determined based at least in part on the turbine speed response to actuation of the first valve and the fully open or fully closed position of the second valve and the turbine bypass valve.

6. The method of claim 1 , wherein the first valve is a turbine bypass valve and wherein the position of the turbine bypass valve is determined based on the turbine speed response comprising a change in turbine speed and not based on a position of one or more other valves in an exhaust gas recirculation system.

7. The method of claim 1 , wherein communicating the information comprises indicating degradation of the first valve based on the turbine speed response upon the actuation of the first valve being commanded.

8. The method of claim 7 , wherein indicating degradation of the first valve includes comparing a change in turbine speed to an expected change in turbine speed, where the expected change in turbine speed is determined from the commanded actuation of the first valve and the fully open or fully closed position of the second valve.

9. The method of claim 8 , further comprising indicating degradation of the first valve when a difference between the change in turbine speed and the expected change in turbine speed is greater than a threshold difference that is indicative of the first valve being degraded.

10. A method, comprising:
via a controller of an engine system:
communicating information relating to a first valve in the engine system based at least in part on a turbine speed response to actuation of the first valve while maintaining a second valve in one of a fully open and fully closed position during actuation of the first valve, where the first valve and the second valve are both positioned in a flow of gas including at least some exhaust gas, wherein communicating the information comprises indicating degradation of the first valve based on the turbine speed response upon the actuation of the first valve being commanded, and wherein indicating degradation of the first valve includes comparing a change in turbine speed to an expected change in turbine speed, where the expected change in turbine speed is determined from the commanded actuation of the first valve and the fully open or fully closed position of the second valve;
indicating degradation of the first valve when a difference between the change in turbine speed and the expected change in turbine speed is greater than a threshold difference that is indicative of the first valve being degraded; and
adjusting engine operation based on the difference between the change in turbine speed and the expected change in turbine speed being greater than the threshold difference.

11. The method of claim 10 , wherein the actuation of the first valve includes a command generated in response to an engine operating condition.

12. The method of claim 10 , further comprising when the difference between the change in turbine speed and the expected change in turbine speed is less than the threshold difference, not indicating valve degradation.

13. The method of claim 10 , wherein the threshold difference reflects an amount of valve degradation.

14. The method of claim 10 , wherein the threshold difference is based on a magnitude of the turbine speed response, where the threshold difference increases as the expected change in turbine speed increases.

15. An engine system, comprising:
an exhaust gas recirculation system configured to route exhaust gas from a donor cylinder exhaust manifold to an exhaust passage in at least a first mode of operation and to an intake passage in at least a second mode of operation;
a first exhaust gas recirculation valve in the exhaust gas recirculation system, the first exhaust gas recirculation valve being controllable to control flow from the donor cylinder exhaust manifold to the exhaust passage and where the first exhaust gas recirculation valve lacks a position sensor associated with the valve for sensing a position of the first exhaust gas recirculation valve;
a second exhaust gas recirculation valve in the exhaust gas recirculation system, the second exhaust gas recirculation valve being controllable to control flow from the donor cylinder exhaust manifold to the intake passage;
a turbine bypass valve for controlling flow of exhaust gas through a high pressure turbine; and
a control unit configured to:
determine the position of the first exhaust gas recirculation valve based on a high pressure turbine speed response upon commanded actuation of the first exhaust gas recirculation valve while positions of the second exhaust gas recirculation valve and the turbine bypass valve are maintained in one of a fully open and fully closed position;
indicate degradation of the first exhaust gas recirculation valve when a difference between an actual change in turbine speed and an expected change in turbine speed is greater than a threshold difference; and
adjust operation of the engine system based on the indicated degradation of the first exhaust gas recirculation valve, where adjusting operation includes adjusting the second exhaust gas recirculation valve to adjust exhaust gas recirculation flow.

16. A method comprising:
via a controller of an engine:
determining a position of a first valve in an exhaust gas recirculation system of the engine based on a turbine speed response upon commanded actuation of the first valve while maintaining a second valve in the exhaust gas recirculation system and a turbine bypass valve in one of a fully open and fully closed position; and
indicating degradation of the first valve when a difference between an actual change in turbine speed and an expected change in turbine speed is greater than a threshold difference and further comprising adj

Assignees

• Gen Electric

Inventors

• Parikh Chirag Bipinchandra
• Kiran Shashi
• Peters Eric David

Classifications

• F02M26/49 Primary

  Detecting, diagnosing or indicating an abnormal function of the EGR system · CPC title

• F02B37/18

  by bypassing exhaust {from the inlet to the outlet of turbine or to the atmosphere} · CPC title

• F02M26/10

  having means to increase the pressure difference between the exhaust and intake system, e.g. venturis, variable geometry turbines, check valves using pressure pulsations or throttles in the air intake or exhaust system · CPC title

• F02D41/005

  according to engine operating conditions · CPC title

• F02M26/43

  in which exhaust from only one cylinder or only a group of cylinders is directed to the intake of the engine · CPC title