Methods and systems for diagnosing an engine intake humidity sensor
IPC분류정보
국가/구분
United States(US) Patent
등록
국제특허분류(IPC7판)
B60W-010/06
B60W-010/22
B60W-020/40
F02D-041/00
F02D-041/04
F02D-041/22
F02M-026/46
출원번호
US-0644419
(2017-07-07)
등록번호
US-10196996
(2019-02-05)
발명자
/ 주소
Dudar, Aed M.
출원인 / 주소
Ford Global Technologies, LLC
대리인 / 주소
Voutyras, Julia
인용정보
피인용 횟수 :
0인용 특허 :
13
초록▼
Methods and systems are provided for a diagnostic of a humidity sensor positioned in an intake of an engine and adjusting engine operation responsive to findings of the diagnostic. In one example, the method may include sealing a vehicle exhaust system of an engine, combusting fuel at cylinders of t
Methods and systems are provided for a diagnostic of a humidity sensor positioned in an intake of an engine and adjusting engine operation responsive to findings of the diagnostic. In one example, the method may include sealing a vehicle exhaust system of an engine, combusting fuel at cylinders of the engine while flowing gases through the engine in a first direction, and then, flowing the combusted exhaust gases through the engine in a reverse, second direction to the humidity sensor positioned in the intake. The method may further include indicating degradation of the humidity sensor based on the output of the humidity sensor while flowing gases in the first and second directions.
대표청구항▼
1. A method for an engine, comprising: after an engine-off duration: combusting fuel at cylinders of the engine while flowing gases through the engine in a first direction;switching to flowing gases through the engine in an opposite, second direction while not combusting fuel;during the flowing gase
1. A method for an engine, comprising: after an engine-off duration: combusting fuel at cylinders of the engine while flowing gases through the engine in a first direction;switching to flowing gases through the engine in an opposite, second direction while not combusting fuel;during the flowing gases in the second direction, obtaining an output of a humidity sensor positioned in an engine intake; andindicating degradation of the humidity sensor based on the output. 2. The method of claim 1, further comprising, in response to indicating degradation of the humidity sensor, adjusting engine operation responsive to an alternate humidity estimate and not based on the output of the humidity sensor. 3. The method of claim 2, wherein adjusting engine operation includes adjusting an exhaust gas recirculation (EGR) flow based on the alternate humidity estimate and not based on the output of the humidity sensor. 4. The method of claim 1, wherein flowing gases through the engine in the first direction includes flowing combustion gases generated while combusting fuel from the cylinders to an exhaust passage via rotating the engine in a forward direction and wherein flowing gases through the engine in the second direction includes flowing the combustion gases from the exhaust passage, through the cylinder, and to the engine intake via rotating the engine in a reverse direction. 5. The method of claim 1, further comprising switching to flowing gases through the engine in the second direction within a threshold duration of stopping combusting fuel at the cylinders and flowing gases through the engine in the first direction. 6. The method of claim 1, further comprising, following the engine-off duration and prior to combusting fuel, adjusting a parameter of a vehicle in which the engine is installed to reduce an amount of water vapor in an exhaust system of the engine from traveling downstream and exiting the exhaust system. 7. The method of claim 6, wherein adjusting the parameter includes one or more of adjusting a valve positioned in the exhaust system into a closed position to seal the exhaust system from atmosphere and block water vapor from exiting the exhaust system and tilting a suspension of the vehicle to be positioned in a nose-facing downward position. 8. The method of claim 1, wherein the engine is installed in an autonomous vehicle and further comprising, prior to shutting off the engine and a beginning of the engine-off duration, in response to a request to perform a diagnostic of the humidity sensor, parking the autonomous vehicle in a nose-facing downward position. 9. The method of claim 1, wherein indicating degradation of the humidity sensor includes indicating degradation in response to the output of the humidity sensor not changing by a threshold amount during flowing the gases in the second direction, and further comprising: in response to the indicating degradation, not adjusting engine operation based on the output of the humidity sensor; andotherwise, adjusting engine operation based on the output of the humidity sensor. 10. The method of claim 1, wherein the engine-off duration includes the engine being shut down for a period of time that is greater than a threshold time and wherein flowing the gases through the engine in the first and second directions and obtaining the output of the humidity sensor are initiated responsive to each of the engine-off duration and an ambient temperature being below a threshold temperature. 11. A method for an engine, comprising: responsive to an engine-off condition and an ambient temperature less than a temperature threshold: rotating the engine in a first direction while combusting fuel for a first duration;within a threshold duration after the first duration, rotating the engine in an opposite, second direction without fueling the engine; andindicating a condition of a humidity sensor positioned in an intake of the engine, upstream of engine cylinders, in response to a change in output of the humidity sensor during the rotating the engine in the first and second directions. 12. The method of claim 11, wherein the first duration is based on an amount of time required to generate a threshold amount of water vapor in the exhaust while rotating the engine in the first direction and combusting fuel, and further comprising, rotating the engine in the second direction for a second duration, the second duration based on a threshold rotational time to flow the generated threshold amount of water vapor past the humidity sensor. 13. The method of claim 12, further comprising indicating degradation of the humidity sensor in response to the change in output of the humidity sensor being outside a threshold of an expected humidity sensor output, where the expected humidity sensor output is determined based on the threshold amount of water vapor. 14. The method of claim 11, further comprising indicating degradation of the humidity sensor in response to the change in the output of the humidity sensor being less than a non-zero threshold, wherein indicating degradation includes one or more of setting a diagnostic flag and alerting a vehicle operator. 15. The method of claim 14, further comprising responsive to the indicating degradation of the humidity sensor, adjusting engine operation based on a set upper threshold ambient humidity level and not based on the output of the humidity sensor. 16. The method of claim 15, wherein adjusting engine operation includes adjusting an exhaust gas recirculation (EGR) valve based on an EGR flow estimate that is based on the set upper threshold ambient humidity level. 17. A system for a hybrid vehicle, comprising: an engine including a plurality of cylinders;a crankshaft and an electric motor, each coupled to a transmission of the hybrid vehicle;an intake manifold;a humidity sensor positioned in the intake manifold; anda controller including non-transitory instructions stored in memory for: following the engine being turned off for a threshold duration: adjusting a component of the hybrid vehicle to block water vapor from exiting out an exhaust system of the engine; andwhile the hybrid vehicle is moving:cranking the engine in a forward direction while combusting fuel at the engine cylinders for a second duration;cranking the engine in a reverse direction while not combusting fuel at the engine cylinders following the second duration; andindicating degradation of the humidity sensor based on a change in output of the humidity sensor during the cranking the engine in the forward direction and the reverse direction. 18. The system of claim 17, further comprising a starter motor coupled to the crankshaft of the engine, and wherein cranking the engine in a reverse direction includes running the starter motor in a reverse direction. 19. The system of claim 17, further comprising an adjustable suspension system coupled to the hybrid vehicle, and wherein adjusting the component of the hybrid vehicle includes adjusting the adjustable suspension system to tilt a suspension of the hybrid vehicle into a nose-downward position. 20. The system of claim 17, further comprising an exhaust tuning valve positioned in an exhaust passage of the exhaust system, and wherein adjusting the component of the hybrid vehicle includes closing the exhaust tuning valve.
연구과제 타임라인
LOADING...
LOADING...
LOADING...
LOADING...
LOADING...
이 특허에 인용된 특허 (13)
Sato, Masahiro; Iwaki, Yoshihisa; Ueno, Masaki; Akazaki, Shusuke; Haga, Takashi; Sato, Tadashi; Miyahara, Yasuyuki, Failure determination device for humidity sensor and control system for exhaust passage changeover valve.
Surnilla, Gopichandra; Makki, Imad Hassan; Kerns, James Michael; Jentz, Robert Roy; Clark, Timothy Joseph; Uhrich, Michael James; Soltis, Richard E., Method and system for humidity sensor diagnostics.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.