CN104895686B - Determine the method and system of the oxygen concentration of engine exhaust - Google Patents
Determine the method and system of the oxygen concentration of engine exhaust Download PDFInfo
- Publication number
- CN104895686B CN104895686B CN201510229236.7A CN201510229236A CN104895686B CN 104895686 B CN104895686 B CN 104895686B CN 201510229236 A CN201510229236 A CN 201510229236A CN 104895686 B CN104895686 B CN 104895686B
- Authority
- CN
- China
- Prior art keywords
- engine
- temperature
- entering
- mass flow
- exhaust gas
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 title claims abstract description 89
- 239000001301 oxygen Substances 0.000 title claims abstract description 89
- 229910052760 oxygen Inorganic materials 0.000 title claims abstract description 89
- 238000000034 method Methods 0.000 title claims abstract description 46
- 239000007789 gas Substances 0.000 claims abstract description 132
- 239000000203 mixture Substances 0.000 claims description 28
- 238000006073 displacement reaction Methods 0.000 claims description 13
- 238000001514 detection method Methods 0.000 claims description 12
- 239000000523 sample Substances 0.000 claims description 9
- 239000000446 fuel Substances 0.000 claims description 7
- 239000002912 waste gas Substances 0.000 abstract 2
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 9
- 230000035945 sensitivity Effects 0.000 description 8
- 238000005259 measurement Methods 0.000 description 3
- 239000000243 solution Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
Landscapes
- Combined Controls Of Internal Combustion Engines (AREA)
Abstract
The method that the present invention discloses the oxygen concentration for determining engine exhaust, first with total air-mass flow of the discharge capacity account engine of the charging efficiency of engine, the rotating speed of engine and engine, afterwards using the temperature for the air for entering engine, into engine waste gas temperature, into engine the temperature of mixed gas and total mass air flow meter of engine add the mass flow of air into engine and enter engine waste gas mass flow, the oxygen concentration of engine exhaust is assured that based on aforementioned data afterwards.The method of the oxygen concentration disclosed by the invention for determining engine exhaust, can quickly determine the oxygen concentration in engine exhaust after the start of engine, and very low to the sensitiveness of pipeline structure, so as to reduce the requirement to engine pipelines layout.The invention also discloses the system for the oxygen concentration for determining engine exhaust.
Description
Technical Field
The invention belongs to the technical field of gas detection, and particularly relates to a method and a system for determining the oxygen concentration of engine exhaust gas.
Background
During operation, vehicles emit significant amounts of nitrogen oxides (e.g., NO and NO2) that are generated under high temperature oxygen-rich conditions. In order to reduce the content of nitrogen oxides in motor vehicle exhaust gases, Exhaust Gas Recirculation (EGR) systems are currently available: a part of exhaust gas discharged by the engine is introduced into an air inlet pipeline of the engine, and the exhaust gas is mixed with air and then enters a cylinder of the engine, so that the temperature and the oxygen content in the cylinder can be reduced, and the content of nitrogen oxides in the exhaust gas is reduced.
In order to ensure the power performance of the engine, a proper amount of exhaust gas is controlled to participate in the recirculation. And the process of determining the amount of exhaust gas participating in the recirculation needs to be performed based on the oxygen content of the engine exhaust. At present, the following modes are mainly adopted for detecting the oxygen content of the exhaust gas of the engine: firstly, an oxygen concentration sensor is additionally arranged on an exhaust pipe of an engine, and the oxygen concentration in exhaust gas is measured in real time through the oxygen concentration sensor; secondly, an oxygen concentration sensor is additionally arranged on an air inlet pipe of the engine, and the oxygen concentration in the exhaust gas is calculated through the measured value of the oxygen concentration sensor and the fuel injection quantity of the engine.
However, the above-described method of detecting the oxygen concentration in the engine exhaust gas has drawbacks: the oxygen concentration sensor can perform oxygen concentration measurement only after being heated to about 700 ℃, so that the oxygen concentration sensor is preheated (usually for 5 to 10 minutes) first after the start of the motor vehicle, and then the oxygen concentration measurement can be performed, and the measurement preparation time is too long.
Disclosure of Invention
In view of the above, the present invention provides a method and a system for determining an oxygen concentration of an engine exhaust gas, which can quickly determine the oxygen concentration in the engine exhaust gas after a vehicle is started.
In order to achieve the purpose, the invention provides the following technical scheme:
the invention discloses a method for determining oxygen concentration of engine exhaust gas, comprising the following steps:
calculating the total intake mass flow of the engine by using the charging efficiency of the engine, the rotating speed of the engine and the engine displacement;
detecting a temperature of air entering the engine, a temperature of exhaust gas entering the engine, and a temperature of a mixture gas entering the engine;
calculating a mass flow of air entering the engine and a mass flow of exhaust gas entering the engine using a temperature of air entering the engine, a temperature of exhaust gas entering the engine, a temperature of a mixture gas entering the engine, and a total intake mass flow of the engine;
using formulasCalculating the oxygen concentration of the mixture gas entering the engine at the present momentWherein m is1For the mass flow of air into the engine, m2For the mass flow of exhaust gas into the engine, m3Is the total intake mass flow of the engine,is the concentration of oxygen in the air and,the first calculation process after the engine is turned on is configured as an initial value, and the subsequent calculation process is configured as the most recently calculated oxygen concentration of the engine exhaust gas;
using formulasCalculating oxygen concentration of engine exhaustWhere F is the amount of oxygen consumed by the fuel injected by the cylinder.
Preferably, calculating the total intake mass flow of the engine using the charge efficiency of the engine, the rotational speed of the engine and the engine displacement comprises:
using the formula m3＝K*Neng/2*VengCalculating the total intake mass flow m of the engine3Where K is the charge efficiency of the engine and NengIs the rotational speed of the engine, VengIs the engine displacement.
Preferably, calculating the mass flow rate of air entering the engine and the mass flow rate of exhaust gas entering the engine using the temperature of air entering the engine, the temperature of exhaust gas entering the engine, the temperature of the mixture gas entering the engine, and the total intake mass flow rate of the engine comprises:
by usingFormula (II)Calculating the mass flow m of air entering the engine1；
Using formulasCalculating the mass flow m of exhaust gas entering the engine2；
Wherein, C1Is the specific heat capacity of air, C2Is the specific heat capacity of the exhaust gas, C3For the specific heat capacity of the mixture entering the engine, T1Temperature of air entering the engine, T2Temperature, T, of exhaust gases entering the engine3Is the temperature of the mixture entering the engine.
Preferably, the temperature of the air entering the engine is detected as: the temperature of air in an intake pipe located after an air cleaner is detected.
Preferably, the temperature of the exhaust gas entering the engine is detected as: and detecting the temperature of the outlet of the EGR valve.
The invention also discloses a system for determining the oxygen concentration of the exhaust gas of the engine, which comprises a first temperature sensor, a second temperature sensor, a third temperature sensor and a processor;
the first temperature sensor is used for detecting the temperature of air entering the engine;
the second temperature sensor is used for detecting the temperature of exhaust gas entering the engine;
the third temperature sensor is used for detecting the temperature of the mixed gas entering the engine;
the treater respectively with first temperature sensor, second temperature sensor and third temperature sensor are connected, the treater is used for calculating the oxygen concentration of engine exhaust gas, specifically includes:
calculating the total intake mass flow of the engine by using the charging efficiency of the engine, the rotating speed of the engine and the engine displacement; calculating a mass flow of air entering the engine and a mass flow of exhaust gas entering the engine using a temperature of air entering the engine, a temperature of exhaust gas entering the engine, a temperature of a mixture gas entering the engine, and a total intake mass flow of the engine; using formulasCalculating the oxygen concentration of the mixture gas entering the engine at the present momentWherein m is1For the mass flow of air into the engine, m2For the mass flow of exhaust gas into the engine, m3Is the total intake mass flow of the engine,is the concentration of oxygen in the air and,the first calculation process after the engine is turned on is configured as an initial value, and the subsequent calculation process is configured as the most recently calculated oxygen concentration of the engine exhaust gas; using formulasCalculating oxygen concentration of engine exhaustWhere F is the amount of oxygen consumed by the fuel injected by the cylinder.
Preferably, the detection probe of the first temperature sensor is provided in an intake pipe located behind the filter.
Preferably, the detection probe of the second temperature sensor is disposed at an outlet of the EGR gas recirculation valve.
Preferably, the detection probe of the third temperature sensor is disposed at an air inlet of the engine.
Preferably, the first temperature sensor, the second temperature sensor and the third temperature sensor are thermistor type temperature sensors.
Therefore, the beneficial effects of the invention are as follows:
the invention discloses a method for determining the oxygen concentration of engine exhaust gas, which comprises the steps of firstly calculating the total intake mass flow of an engine by utilizing the charging efficiency of the engine, the rotating speed of the engine and the displacement of the engine, then calculating the mass flow of air entering the engine and the mass flow of exhaust gas entering the engine by utilizing the temperature of air entering the engine, the temperature of exhaust gas entering the engine, the temperature of mixed gas entering the engine and the total intake mass flow of the engine, and then determining the oxygen concentration of the engine exhaust gas based on the data. According to the method for determining the oxygen concentration of the engine exhaust gas, the used detection data only comprise three temperature values, and the temperature sensor can detect the temperature at any time, so that the oxygen concentration of the engine exhaust gas can be quickly determined after the engine is started based on the method disclosed by the invention. In addition, because the sensitivity of the temperature sensor to the airflow change is very low, the temperature can be accurately detected even if the airflow is unstable, therefore, the sensitivity of the method disclosed by the invention to the pipeline structure is very low, and the requirement on the layout of the engine pipeline can be reduced.
The invention discloses a system for determining the oxygen concentration of engine exhaust gas, which detects the temperature of air entering an engine, the temperature of exhaust gas entering the engine and the temperature of mixed gas entering the engine through three temperature sensors, a processor calculates the total intake mass flow of the engine by utilizing the charging efficiency of the engine, the rotating speed of the engine and the discharge capacity of the engine, and then the oxygen concentration of the engine exhaust gas can be determined based on the temperature values detected by the three temperature sensors and the total intake mass flow of the engine. According to the system for determining the oxygen concentration of the engine exhaust gas, the used detection data only comprise three temperature values, and the temperature sensor can detect the temperature at any time, so that the oxygen concentration of the engine exhaust gas can be quickly determined after the engine is started based on the system disclosed by the invention. In addition, because the temperature sensor has low sensitivity to airflow change, the temperature can be accurately detected even if the airflow is unstable, and therefore, the system disclosed by the invention has low sensitivity to the pipeline structure, and the requirement on the layout of the engine pipeline can be reduced.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is a flow chart of a method of determining oxygen concentration of an engine exhaust in accordance with the present disclosure;
FIG. 2 is a schematic diagram illustrating a system for determining oxygen concentration of engine exhaust in accordance with the present disclosure.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention relates to a method for determining the oxygen concentration in an engine exhaust gas, on the basis of which the oxygen concentration in the engine exhaust gas can be determined quickly after the start of a motor vehicle.
Referring to FIG. 1, FIG. 1 is a flow chart illustrating a method of determining oxygen concentration of engine exhaust in accordance with the present disclosure. The method comprises the following steps:
step S1: and calculating the total intake mass flow of the engine by using the charging efficiency of the engine, the rotating speed of the engine and the engine displacement.
The vehicle controller of the motor vehicle controls the EGR valve (which may be a solenoid valve) to open and adjusts the opening degree of the EGR valve so that a portion of exhaust gas emitted from the engine may reenter an intake pipe of the engine, and thus, gas entering the engine includes both fresh air and a portion of exhaust gas.
In practice, the total intake mass airflow of the engine may be calculated using equation 1.
m3＝K*Neng/2*Veng(formula 1)
Wherein m is3Is the total intake mass flow of the engine, K is the charging efficiency of the engine, NengIs the rotational speed of the engine, VengIs the engine displacement.
Step S2: the temperature of air entering the engine, the temperature of exhaust gas entering the engine, and the temperature of the mixture gas entering the engine are detected.
Three temperature sensors are arranged on an air inlet pipeline of the engine, wherein one temperature sensor is used for detecting the temperature of air entering the engine, the other temperature sensor is used for detecting the temperature of exhaust gas entering the engine, and the third temperature sensor is used for detecting the temperature of mixed gas entering the engine.
Step S3: the mass flow of air into the engine and the mass flow of exhaust gas into the engine are calculated.
In operation, the mass flow rate of air entering the engine and the mass flow rate of exhaust gas entering the engine are calculated using the temperature of air entering the engine, the temperature of exhaust gas entering the engine, the temperature of the air-fuel mixture entering the engine, and the total intake mass flow rate of the engine.
Equation 2 can be derived from the heat balance principle:
C1*m1*T1+C2*m2*T2＝C3*m3*T3(formula 2)
Wherein:
C1is the specific heat capacity of air; m is1Mass flow rate of air entering the engine; t is1Is the temperature of the air entering the engine; c2Is the specific heat capacity of the exhaust gas; m is2Mass flow of exhaust gas into the engine; t is2Is the temperature of the exhaust gas entering the engine; c3Is the specific heat capacity of the mixed gas entering the engine; m is3Is the total intake mass flow of the engine; t is3Is the temperature of the mixture entering the engine.
In addition, equation 3 can be obtained according to the principle of conservation of mass:
m1+m2＝m3(formula 3)
According to the formula 1, the formula 2 and the formula 3, the mass flow m of the air entering the engine can be calculated1And the mass flow m of exhaust gas entering the engine2Specifically, the method comprises the following steps:
step S4: and calculating the oxygen concentration of the mixed gas entering the engine at the current moment.
In practice, the oxygen concentration of the mixture gas entering the engine at the present time is calculated using equation 4.
(formula 4)
Wherein,oxygen concentration, m, of the mixture gas entering the engine at the present moment1For the mass flow of air into the engine, m2For the mass flow of exhaust gas into the engine, m3Is the total intake mass flow of the engine,is the concentration of oxygen in the air and,is configured as an initial value in a first calculation process after the engine is turned on, and is configured as an oxygen concentration of the engine exhaust gas calculated last in a subsequent calculation process.
For the equation 4The values of (a) are explained in detail:
if the operation of determining the oxygen concentration in the engine exhaust gas is performed for the first time after the engine is turned on, that is, the step S4 is performed for the first time, it will beConfigured to an initial value, which may be the oxygen concentration of air. If it is the ith time after the engine is started (i is large)At integer of 1) to perform step S4, then in the ith calculation processConfigured to calculate the oxygen concentration of the engine exhaust gas i-1. That is, the one used in step S4Are iterated one after another.
Step S5: the oxygen concentration of the engine exhaust is calculated.
In practice, the oxygen concentration of the engine exhaust is calculated using equation 5:
(formula 5)
Wherein,f is the amount of oxygen consumed by the fuel injected by the cylinder, a calibrated value, as the oxygen concentration of the engine exhaust.
The invention discloses a method for determining the oxygen concentration of engine exhaust gas, which comprises the steps of firstly calculating the total intake mass flow of an engine by utilizing the charging efficiency of the engine, the rotating speed of the engine and the displacement of the engine, then calculating the mass flow of air entering the engine and the mass flow of exhaust gas entering the engine by utilizing the temperature of air entering the engine, the temperature of exhaust gas entering the engine, the temperature of mixed gas entering the engine and the total intake mass flow of the engine, and then determining the oxygen concentration of the engine exhaust gas based on the data. According to the method for determining the oxygen concentration of the engine exhaust gas, the used detection data only comprise three temperature values, and the temperature sensor can detect the temperature at any time, so that the oxygen concentration of the engine exhaust gas can be quickly determined after the engine is started based on the method disclosed by the invention. In addition, because the sensitivity of the temperature sensor to the airflow change is very low, the temperature can be accurately detected even if the airflow is unstable, therefore, the sensitivity of the method disclosed by the invention to the pipeline structure is very low, and the requirement on the layout of the engine pipeline can be reduced.
Preferably, the temperature of the air entering the engine is detected by: the temperature of air in an intake pipe located after an air cleaner is detected. The air cleaner is arranged on an air inlet pipeline of the engine and used for filtering air entering the engine.
In addition, detecting the temperature of the exhaust gas entering the engine may be configured to: and detecting the temperature of the outlet of the EGR valve.
The invention also discloses a system for determining the oxygen concentration of engine exhaust, which is structurally shown in FIG. 2 and comprises: a first temperature sensor 100, a second temperature sensor 200, a third temperature sensor 300, and a processor 400.
Wherein:
the first temperature sensor 100 is used to detect the temperature of air entering the engine.
The second temperature sensor 200 is used to detect the temperature of the exhaust gas entering the engine.
The third temperature sensor 300 is used to detect the temperature of the mixture gas entering the engine.
The processor 400 is connected to the first temperature sensor 100, the second temperature sensor 200 and the third temperature sensor 300, respectively, and the processor 400 is used for calculating the oxygen concentration of the engine exhaust, which is briefly described herein, and other parts not mentioned are referred to the above description:
the processor 400 calculates the total intake mass flow of the engine using the charge efficiency of the engine, the speed of the engine, and the engine displacement. Processor 400 then utilizes the temperature of the air of the engine, the temperature of the exhaust gas entering the engine, the temperature of the mixture of gases entering the engine, and the engineThe mass flow of air entering the engine and the mass flow of exhaust gas entering the engine are calculated. Processor 400 then calculates the oxygen concentration of the mixture entering the engine at the present time using equation 4Whereinthe first calculation process after the engine is turned on is configured as an initial value, and the subsequent calculation process is configured as the most recently calculated oxygen concentration of the engine exhaust gas. Processor 400 then calculates the oxygen concentration of the engine exhaust using equation 5。
The invention discloses a system for determining the oxygen concentration of engine exhaust gas, which detects the temperature of air entering an engine, the temperature of exhaust gas entering the engine and the temperature of mixed gas entering the engine through three temperature sensors, a processor calculates the total intake mass flow of the engine by utilizing the charging efficiency of the engine, the rotating speed of the engine and the discharge capacity of the engine, and then the oxygen concentration of the engine exhaust gas can be determined based on the temperature values detected by the three temperature sensors and the total intake mass flow of the engine. According to the system for determining the oxygen concentration of the engine exhaust gas, the used detection data only comprise three temperature values, and the temperature sensor can detect the temperature at any time, so that the oxygen concentration of the engine exhaust gas can be quickly determined after the engine is started based on the system disclosed by the invention. In addition, because the temperature sensor has low sensitivity to airflow change, the temperature can be accurately detected even if the airflow is unstable, and therefore, the system disclosed by the invention has low sensitivity to the pipeline structure, and the requirement on the layout of the engine pipeline can be reduced.
In practice, processor 400 may calculate the total intake mass flow of the engine using equation 1.
In addition, processor 400 may utilize formulasCalculating the mass flow m of air entering the engine1Using the formulaCalculating the mass flow m of exhaust gas entering the engine2。
Preferably, the detection probe of the first temperature sensor 100 is provided in the intake pipe located behind the filter so as to more accurately detect the temperature of the air taken into the engine.
In addition, as a preferable aspect, a detection probe of the second temperature sensor 200 may be provided at an outlet of the EGR valve in order to more accurately detect the temperature of the exhaust gas entering the engine.
In addition, as a preferable aspect, the detection probe of the third temperature sensor 300 may be provided at an air intake of the engine, so as to more accurately detect the temperature of the mixture gas entering the engine.
In implementation, the first temperature sensor 100, the second temperature sensor 200, and the third temperature sensor 300 may preferably use thermistor type temperature sensors.
Finally, it should also be noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (9)
1. A method of determining an oxygen concentration of an engine exhaust, the method comprising:
calculating the total intake mass flow of the engine by using the charging efficiency of the engine, the rotating speed of the engine and the engine displacement;
detecting a temperature of air entering the engine, a temperature of exhaust gas entering the engine, and a temperature of a mixture gas entering the engine;
calculating a mass flow of air entering the engine and a mass flow of exhaust gas entering the engine using a temperature of air entering the engine, a temperature of exhaust gas entering the engine, a temperature of a mixture gas entering the engine, and a total intake mass flow of the engine;
using formulasCalculating the oxygen concentration of the mixture gas entering the engine at the present momentWherein m is1For the mass flow of air into the engine, m2For the mass flow of exhaust gas into the engine, m3Is the total intake mass flow of the engine,is the concentration of oxygen in the air and,the first calculation process after the engine is turned on is configured as an initial value, and the subsequent calculation process is configured as the most recently calculated oxygen concentration of the engine exhaust gas;
using formulasCalculating oxygen concentration of engine exhaustWherein F is the amount of oxygen consumed by the fuel injected by the cylinder;
wherein calculating the mass flow of air entering the engine and the mass flow of exhaust gas entering the engine using the temperature of air entering the engine, the temperature of exhaust gas entering the engine, the temperature of the mixture entering the engine, and the total intake mass flow of the engine comprises:
using formulasCalculating the mass flow m of air entering the engine1；
Using formulasCalculating the mass flow m of exhaust gas entering the engine2；
Wherein, C1Is the specific heat capacity of air, C2Is the specific heat capacity of the exhaust gas, C3For the specific heat capacity of the mixture entering the engine, T1Temperature of air entering the engine, T2Temperature, T, of exhaust gases entering the engine3Is the temperature of the mixture entering the engine.
2. The method of claim 1, wherein calculating a total intake mass flow of the engine using a charge efficiency of the engine, a speed of the engine, and a displacement of the engine comprises:
using the formula m3＝K*Neng/2*VengCalculating the total intake mass flow m of the engine3Where K is the charge efficiency of the engine and NengIs the rotational speed of the engine, VengIs the engine displacement.
3. The method of claim 1, wherein detecting the temperature of air entering the engine is: the temperature of air in an intake pipe located after an air cleaner is detected.
4. The method of claim 3, wherein sensing the temperature of the exhaust gas entering the engine is: and detecting the temperature of the outlet of the EGR valve.
5. A system for determining an oxygen concentration of an exhaust gas of an engine, comprising a first temperature sensor, a second temperature sensor, a third temperature sensor, and a processor;
the first temperature sensor is used for detecting the temperature of air entering the engine;
the second temperature sensor is used for detecting the temperature of exhaust gas entering the engine;
the third temperature sensor is used for detecting the temperature of the mixed gas entering the engine;
the treater respectively with first temperature sensor, second temperature sensor and third temperature sensor are connected, the treater is used for calculating the oxygen concentration of engine exhaust gas, specifically includes:
calculating the total intake mass flow of the engine by using the charging efficiency of the engine, the rotating speed of the engine and the engine displacement; calculating a mass flow of air entering the engine and a mass flow of exhaust gas entering the engine using a temperature of air entering the engine, a temperature of exhaust gas entering the engine, a temperature of a mixture gas entering the engine, and a total intake mass flow of the engine; using formulasCalculating the oxygen concentration of the mixture gas entering the engine at the present momentWherein m is1For the mass flow of air into the engine, m2For the mass flow of exhaust gas into the engine, m3Is the total intake mass flow of the engine,is the concentration of oxygen in the air and,the first calculation process after the engine is turned on is configured as an initial value, and the subsequent calculation process is configured as the most recently calculated oxygen concentration of the engine exhaust gas; using formulasCalculating oxygen concentration of engine exhaustWherein F is the amount of oxygen consumed by the fuel injected by the cylinder;
wherein calculating the mass flow of air entering the engine and the mass flow of exhaust gas entering the engine using the temperature of air entering the engine, the temperature of exhaust gas entering the engine, the temperature of the mixture entering the engine, and the total intake mass flow of the engine comprises:
using formulasCalculating the mass flow m of air entering the engine1；
Using formulasCalculating the mass flow m of exhaust gas entering the engine2；
Wherein, C1Is the specific heat capacity of air, C2Is the specific heat capacity of the exhaust gas, C3For the specific heat capacity of the mixture entering the engine, T1Temperature of air entering the engine, T2Temperature, T, of exhaust gases entering the engine3Is the temperature of the mixture entering the engine.
6. The system of claim 5, wherein the sensing probe of the first temperature sensor is disposed in the intake pipe behind the filter.
7. The system according to claim 5 or 6, wherein the detection probe of the second temperature sensor is arranged at the outlet of an EGR-EGR valve.
8. The system of claim 7, wherein the sensing probe of the third temperature sensor is disposed at an air intake of the engine.
9. The system of claim 5, wherein the first, second, and third temperature sensors are thermistor temperature sensors.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510229236.7A CN104895686B (en) | 2015-05-07 | 2015-05-07 | Determine the method and system of the oxygen concentration of engine exhaust |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510229236.7A CN104895686B (en) | 2015-05-07 | 2015-05-07 | Determine the method and system of the oxygen concentration of engine exhaust |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104895686A CN104895686A (en) | 2015-09-09 |
| CN104895686B true CN104895686B (en) | 2018-04-03 |
Family
ID=54028586
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510229236.7A Active CN104895686B (en) | 2015-05-07 | 2015-05-07 | Determine the method and system of the oxygen concentration of engine exhaust |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104895686B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107489552B (en) * | 2016-12-12 | 2020-09-18 | 宝沃汽车（中国）有限公司 | Oil injection control method, device and system and vehicle |
| CN112648709A (en) * | 2020-12-04 | 2021-04-13 | 中国航空工业集团公司西安航空计算技术研究所 | Automatic oxygen concentration maintaining and controlling device for closed space |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1637254A (en) * | 2003-12-25 | 2005-07-13 | 株式会社电装 | Control device for internal combustion engine |
| CN103485908A (en) * | 2012-06-07 | 2014-01-01 | 通用汽车环球科技运作有限责任公司 | Humidity determination and compensation systems and methods using an intake oxygen sensor |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005299600A (en) * | 2004-04-15 | 2005-10-27 | Toyota Motor Corp | Fuel supply control device for internal combustion engine |
| JP4730122B2 (en) * | 2006-02-07 | 2011-07-20 | いすゞ自動車株式会社 | Engine control method and engine control system |
| EP2098710B1 (en) * | 2008-03-04 | 2016-07-27 | GM Global Technology Operations LLC | A method for estimating the oxygen concentration in internal combustion engines |
-
2015
- 2015-05-07 CN CN201510229236.7A patent/CN104895686B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1637254A (en) * | 2003-12-25 | 2005-07-13 | 株式会社电装 | Control device for internal combustion engine |
| CN103485908A (en) * | 2012-06-07 | 2014-01-01 | 通用汽车环球科技运作有限责任公司 | Humidity determination and compensation systems and methods using an intake oxygen sensor |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104895686A (en) | 2015-09-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10156213B2 (en) | Humidity sensor diagnostic method using condensation clearing heater | |
| JP4158679B2 (en) | Engine intake gas temperature estimation device | |
| CN102621212B (en) | Determine oxygen concentration O in air-flow2method | |
| JP6144568B2 (en) | Sensor output value estimation device | |
| US6877369B2 (en) | EGR-gas flow rate estimation apparatus for internal combustion engine | |
| CN103122798B (en) | Sensor control device and sensor control system | |
| US9239025B2 (en) | Condensation detection systems and methods | |
| JP6146192B2 (en) | Diagnostic equipment | |
| CN104564359B (en) | Internal combustion engine control apparatus | |
| CN108571391A (en) | The control device and control method of internal combustion engine | |
| WO2009139507A1 (en) | Soot discharge estimating device for internal combustion engines | |
| JP4618312B2 (en) | Exhaust gas sensor control device | |
| CN104895686B (en) | Determine the method and system of the oxygen concentration of engine exhaust | |
| JP2015031170A (en) | State detection device for exhaust system | |
| CN101429900A (en) | Method and apparatus for controlling diesel engine | |
| JP2006057523A (en) | Failure diagnosis device for engine control system | |
| EP3128159B1 (en) | Method to control a low-pressure exhaust gas recirculation egr circuit in an internal combustion engine | |
| CN105612338B (en) | engine | |
| JP2013189964A (en) | Control device of engine | |
| US7594389B2 (en) | Method for diagnosing a secondary-air system of an internal combustion engine | |
| JP2006343136A (en) | Partial pressure detector of steam, suction flow rate detector of engine and internal pressure detector of collector | |
| JP2010169039A (en) | Egr flow rate measuring device for internal combustion engine | |
| JP5295078B2 (en) | Gas flow measuring device for internal combustion engine | |
| JP2004150376A (en) | Gas temperature estimation device for internal combustion engine | |
| JP2005133604A (en) | Intake gas temperature inferring device for engine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |