阅读说明：本技术 发动机的失火检测方法、装置和系统 (The fire detecting method of engine, device and system ) 是由 于广 孟毅 于 2018-05-25 设计创作，主要内容包括：本发明提供一种发动机的失火检测方法、装置和系统,该方法包括：获取步骤,获取所述发动机中的曲轴传感器检测到的第一数据以及所述发动机中的爆震传感器检测到的当前数据；通过时间计算步骤,根据所述第一数据,计算所述发动机中的多个气缸各自的通过时间；失火判断参数计算步骤,根据所述通过时间,计算所述多个气缸中的当前气缸与其他气缸的动能差,并将最大的动能差作为失火判断参数；滤波参数计算步骤,根据所述当前数据以及历史滤波数据,计算当前滤波数据；失火判断步骤,当所述失火判断参数大于等于第一阈值且所述当前滤波数据小于第二阈值时,判断所述当前气缸失火。(The present invention provides a kind of fire detecting method of engine, device and system, this method comprises: obtaining step, obtains the current data that the detonation sensor in the first data and the engine that the crankshaft sensor in the engine detects detects；Step, which is calculated, by the time calculates multiple cylinders in the engine respectively through the time according to first data；It catches fire and judges that parameter calculates step, according to described by the time, the kinetic energy for calculating the current cylinder and other cylinders in the multiple cylinder is poor, and judges parameter using maximum kinetic energy difference as catching fire；Filtering parameter calculates step, according to the current data and history filtering data, calculates current filter data；Catch fire judgment step, when it is described catch fire judge that parameter is more than or equal to first threshold and the current filter data are less than second threshold when, judge that the current cylinder catches fire.)

1. a kind of fire detecting method of engine, which is characterized in that the described method includes:

Obtaining step obtains quick-fried in the first data and the engine that the crankshaft sensor in the engine detects The current data that shake sensor detects；

Calculate step by the time, according to first data, calculate multiple cylinders in the engine respectively through when Between；

It catches fire and judges that parameter calculates step, according to described by the time, calculate current cylinder in the multiple cylinder and other The kinetic energy of cylinder is poor, and judges parameter using maximum kinetic energy difference as catching fire；

Filtering parameter calculates step, according to the current data and history filtering data, calculates current filter data；

It catches fire judgment step, when described catch fire judges that parameter is more than or equal to first threshold and the current filter data less than second When threshold value, judge that the current cylinder catches fire.

2. fire detecting method as described in claim 1, which is characterized in that described by the time is cylinder in combustion stroke Pass through the time needed for predetermined angular.

3. fire detecting method as claimed in claim 2, which is characterized in that described catch fire judges that parameter calculates step and includes:

Kinetic energy difference calculates step, calculates the current cylinder according to formula (1) and the respective kinetic energy of other cylinders is poor,

Wherein, Ei indicates that the kinetic energy of the current cylinder i, Ej indicate that the kinetic energy of the cylinder j in other described cylinders, J indicate institute State the rotary inertia of current cylinder i and the cylinder j, it is described predetermined to indicate that the current cylinder i and the cylinder j pass through by L Angle, Ti indicate the current cylinder i by the time, Tj indicates that the cylinder j's passes through the time；

It determines step, the current cylinder and the respective kinetic energy of other cylinders that step calculates is calculated according to the kinetic energy difference Maximum kinetic energy difference is determined as described catch fire and judges parameter by difference.

4. fire detecting method as claimed in claim 3, which is characterized in that it is calculated in step in the filtering parameter, according to Formula (2) calculates the current filter data,

Y (t)=wy (t)+(1-w) Y (t-1) formula (2)

Wherein, Y (t) indicates the current filter data in time t, and y (t) indicates that the detonation sensor is measured in time t The current data arrived, w are filter weights, and it is the filtering number in time t-1 that Y (t-1), which indicates the history filtering data, According to.

5. such as fire detecting method of any of claims 1-4, which is characterized in that in the judgment step of catching fire In, when described catch fire judges that parameter is more than or equal to the first threshold and the current filter data are more than or equal to second threshold When value, judgement is currently bumpy road.

6. a kind of misfire detecting apparatus of engine, which is characterized in that described device includes:

Acquiring unit obtains quick-fried in the first data and the engine that the crankshaft sensor in the engine detects The current data that shake sensor detects；

By time calculating unit, according to first data, calculate multiple cylinders in the engine respectively through when Between；

It catches fire and judges parameter calculation unit, according to described by the time, calculate current cylinder in the multiple cylinder and other The kinetic energy of cylinder is poor, and judges parameter using maximum kinetic energy difference as catching fire；

Filtering parameter computing unit calculates current filter data according to the current data and history filtering data；

Catch fire judging unit, when described catch fire judges that parameter is more than or equal to first threshold and the current filter data less than second When threshold value, judge that the current cylinder catches fire.

7. misfire detecting apparatus as claimed in claim 6, which is characterized in that described by the time is cylinder in combustion stroke Pass through the time needed for predetermined angular.

8. misfire detecting apparatus as claimed in claim 7, which is characterized in that described catch fire judges that parameter calculation unit includes:

Kinetic energy difference computing unit calculates the current cylinder according to formula (1) and the respective kinetic energy of other cylinders is poor,

Wherein, Ei indicates that the kinetic energy of the current cylinder i, Ej indicate that the kinetic energy of the cylinder j in other described cylinders, J indicate institute State the rotary inertia of current cylinder i and the cylinder j, it is described predetermined to indicate that the current cylinder i and the cylinder j pass through by L Angle, Ti indicate the current cylinder i by the time, Tj indicates that the cylinder j's passes through the time；

Determination unit, it is respective dynamic according to the calculated current cylinder of the kinetic energy difference computing unit and other described cylinders Can be poor, maximum kinetic energy difference is determined as described catch fire and judges parameter.

9. misfire detecting apparatus as claimed in claim 8, which is characterized in that in the filtering parameter computing unit, according to Formula (2) calculates the current filter data,

Y (t)=wy (t)+(1-w) Y (t-1) formula (2)

Wherein, Y (t) indicates the current filter data in time t, and y (t) indicates that the detonation sensor is detected in time t The current data arrived, w are filter weights, and it is the filtering number in time t-1 that Y (t-1), which indicates the history filtering data, According to.

10. the misfire detecting apparatus as described in any one of claim 6-9, which is characterized in that when described catch fire judges parameter More than or equal to the first threshold and when the current filter data are more than or equal to the second threshold, the judging unit that catches fire Judgement is currently bumpy road.

11. a kind of detection system of catching fire of engine, which is characterized in that the system comprises: crankshaft sensor, pinking sensing The misfire detecting apparatus of device, multiple cylinders and the engine as described in any one of claim 6-10.

Technical field

The present invention relates to the fire detecting methods of engine, device and system.

Background technique

Safety that online misfire diagnosis runs engine, exhaust emissions have significant impact.Catching fire, it is inaccurate to detect It cannot be found in time when will lead to gasoline engine misfire, the discharge of pernicious gas increases.Therefore realize that accurate cylinder loses Fire detection reduces air pollution tool and has very important significance to exhaust emissions is reduced.

Sentencing for misfire fault can be realized by engine cylinder pressure sensor or crankshaft sensor under normal conditions It is fixed.Although cylinder pressure sensors detection accuracy is high, since its cost high life is short, so general volume production engine can use Crankshaft sensor realizes detection of catching fire.

In Chinese patent CN200610093868, a kind of fire detecting method based on crankshaft sensor is disclosed.Base In each cylinder of engine in combustion stroke, according to the data of crankshaft sensor calculate each cylinder by the time, pass through ratio Whether the time difference between more normal combustion cylinders and misfiring cylinder is greater than threshold value to realize the detection for phenomenon of catching fire.

Under normal conditions, some cylinder of engine operation occur catching fire phenomenon when, this detection method is can to take Obtain good effect.But if when engine two of them or three cylinders continuously catch fire, caught fire due to two Time difference between cylinder is likely less than threshold value and can not detect and catch fire.It is poor additionally, due to cylinder time when passing through bumpy road Also more acutely, continuous cylinder misfire phenomenon may also be erroneously interpreted as bumpy road, and can not detect and catch fire.These all can Deteriorate the exhaust emissions of automobile.

Summary of the invention

In order to solve the problems in the prior art, the present invention provides a kind of fire detecting method of engine, this method Include:

Obtaining step obtains in the first data and the engine that the crankshaft sensor in the engine detects The current data that detects of detonation sensor；

Step is calculated by the time, according to first data, the multiple cylinders calculated in the engine are respective logical Spend the time；

Catch fire and judge that parameter calculates step, according to described by the time, calculate current cylinder in the multiple cylinder with The kinetic energy of other cylinders is poor, and judges parameter using maximum kinetic energy difference as catching fire；

Filtering parameter calculates step, according to the current data and history filtering data, calculates current filter data；

It catches fire judgment step, when described catch fire judges that parameter is more than or equal to first threshold and the current filter data are less than When second threshold, judge that the current cylinder catches fire.

Wherein, it is described by the time be cylinder in combustion stroke by the time needed for predetermined angular.

Wherein, described catch fire judges that parameter calculates step and includes:

Kinetic energy difference calculates step, calculates the current cylinder according to formula (1) and the respective kinetic energy of other cylinders is poor,

Wherein, Ei indicates that the kinetic energy of the current cylinder i, Ej indicate the kinetic energy of the cylinder j in other described cylinders, J table Show the rotary inertia of the current cylinder i and the cylinder j, it is described that L indicates that the current cylinder i and the cylinder j pass through Predetermined angular, Ti indicate the current cylinder i by the time, Tj indicates that the cylinder j's passes through the time；

Determine step, the current cylinder and other described cylinders calculated according to kinetic energy difference calculating step is respective Kinetic energy is poor, and maximum kinetic energy difference is determined as described catch fire and judges parameter.

Wherein, it is calculated in step in the filtering parameter, calculates the current filter data according to formula (2),

Y (t)=wy (t)+(1-w) Y (t-1) formula (2)

Wherein, Y (t) indicates the current filter data in time t, and y (t) indicates the detonation sensor in time t The current data measured, w are filter weights, and it is the filter in time t-1 that Y (t-1), which indicates the history filtering data, Wave number evidence.

Wherein, in the judgment step of catching fire, when described catch fire judges that parameter is more than or equal to the first threshold and institute When stating current filter data more than or equal to the second threshold, judgement is currently bumpy road.

The present invention also provides a kind of misfire detecting apparatus of engine, which includes:

Acquiring unit obtains in the first data and the engine that the crankshaft sensor in the engine detects The current data that detects of detonation sensor；

By time calculating unit, according to first data, the multiple cylinders calculated in the engine are respective logical Spend the time；

Catch fire and judge parameter calculation unit, according to described by the time, calculate current cylinder in the multiple cylinder with The kinetic energy of other cylinders is poor, and judges parameter using maximum kinetic energy difference as catching fire；

Filtering parameter computing unit calculates current filter data according to the current data and history filtering data；

Catch fire judging unit, when described catch fire judges that parameter is more than or equal to first threshold and the current filter data are less than When second threshold, judge that the current cylinder catches fire.

Further, the present invention also provides a kind of detection system of catching fire of engine, which includes: crankshaft sensor, quick-fried Shake the misfire detecting apparatus of sensor, multiple cylinders and engine as described above.

By the invention it is possible to avoid two cylinders of comparison while catching fire to cause to be difficult to the case where judging.In addition, this hair It is bright accurately to judge currently to catch fire or bumpy road, to avoid the occurrence of erroneous judgement.

Detailed description of the invention

Fig. 1 is the structural schematic diagram of the detection system of catching fire of engine according to an embodiment of the present invention；

Fig. 2 is the structural schematic diagram of the misfire detecting apparatus of engine according to an embodiment of the present invention；

Fig. 3 is the flow chart of the fire detecting method of engine according to an embodiment of the present invention；

Fig. 4 is that catching fire in the misfire detecting apparatus of engine according to an embodiment of the present invention judges parameter calculation unit Structural schematic diagram；

Fig. 5 is the stream for judging that parameter calculates step that catches fire of the fire detecting method of engine according to an embodiment of the present invention Cheng Tu；

Fig. 6 is the effect explanatory diagram of the fire detecting method of engine according to an embodiment of the present invention；

Fig. 7 is another effect explanatory diagram of the fire detecting method of engine according to an embodiment of the present invention.

Specific embodiment

With reference to the accompanying drawing, the embodiment of the present invention is described in detail.

Fig. 1 is the structural schematic diagram of the detection system 10 of catching fire of engine according to an embodiment of the present invention.As shown in Figure 1, The detection system 10 of catching fire includes multiple cylinder 1a-1d, detonation sensor 5, crankshaft sensor 4, piston 2, crankshaft 3, Yi Jifa The misfire detecting apparatus 6 of motivation.It hereinafter, can be after digital number 1 plus corresponding when each cylinder is described respectively Letter, such as 1a, 1b, 1c or 1d, and in the case of other are then only indicated with number 1.

By the gas burning entered in cylinder 1, band piston 2 makees iterative motion.It is connected with cylinder 1, piston 2 Crankshaft 3 be configured with crankshaft sensor 4, position that the available piston 2 of the signal detected based on crankshaft sensor 4 is moved, Speed and the revolving speed of engine etc..Configured with the detonation sensor that can detecte engine knock phenomenon on cylinder 1 (for example, cylinder 1a) 5.The detonation sensor is the sensor of acceleration type, and original signal is the vibration signal of 1 body of cylinder.As shown in Figure 1, losing Fire detection device 6 can for example be passed through by control unit of engine ECU (Electronic Control Unit) Lai Shixian CAN bus 7 is connected with crankshaft sensor 4, detonation sensor 5 and each executing agency.In this example, crankshaft sensor 4 is, for example, Hall-type position sensor is but it is also possible to be other kinds of sensor.

Fig. 2 is the structural schematic diagram of the misfire detecting apparatus 6 of engine according to an embodiment of the present invention.As shown in Fig. 2, losing Fire detection device 6 include acquiring unit 61, by time calculating unit 62, catching fire judges parameter calculation unit 63, filtering parameter Computing unit 64 and the judging unit 65 that catches fire.

Fig. 3 is the flow chart of the fire detecting method of engine according to an embodiment of the present invention.Below with reference to Fig. 2 and Fig. 3 The embodiment of the present invention is described in detail.

As shown in figure 3, the acquiring unit 61 in misfire detecting apparatus 6 obtains the crankshaft sensing in engine in step S31 The current data that the detonation sensor 5 in the first data and engine that device 4 detects detects.Wherein, catch fire detection dress The acquiring unit 61 set in 6 obtains above-mentioned first data and above-mentioned current data via CAN bus 7 shown in FIG. 1.

The first data that crankshaft sensor 4 detects are as in the prior art, and I will not elaborate.Detonation sensor 5 current datas detected refer to the data that detonation sensor 5 is measured in time t, as in the prior art, here No longer it is described in detail.

In step S32, by time calculating unit 62 according to the first data, the multiple cylinders 1 calculated in engine are respective Pass through the time.Wherein, by the time be each cylinder 1 in combustion stroke by the time needed for predetermined angular L.

In step S33, catches fire and judge that parameter calculation unit 63 according to above by the time, calculates working as in multiple cylinders 1 The kinetic energy of front air cylinder and other cylinders is poor, and judges parameter using maximum kinetic energy difference as catching fire.

Fig. 4 is that catching fire in the misfire detecting apparatus 6 of engine according to an embodiment of the present invention judges parameter calculation unit 63 structural schematic diagram.Judge that parameter calculation unit 63 further includes kinetic energy difference computing unit 631 and determines as shown in figure 4, catching fire Unit 632.

Fig. 5 is the stream for judging that parameter calculates step that catches fire of the fire detecting method of engine according to an embodiment of the present invention Cheng Tu.In step S331, kinetic energy difference computing unit 631 calculates current cylinder and the respective kinetic energy of other cylinders according to formula (1) Difference,

Wherein, Ei indicates that the kinetic energy of current cylinder i, Ej indicate that the kinetic energy of the cylinder j in other cylinders, J indicate current gas The rotary inertia of cylinder i and cylinder j, L indicate that the predetermined angular that current cylinder i and cylinder j passes through, Ti indicate that current cylinder i's is logical The time is spent, Tj indicates that cylinder j's passes through the time.

For example, current cylinder i is the cylinder 1a in Fig. 1, the cylinder j in other cylinders is the cylinder 1b in Fig. 1, then can To calculate the kinetic energy difference D of cylinder 1a and cylinder 1b according to above-mentioned formula (1)_ab.It is also possible to be calculated according to above-mentioned formula (1) The cylinder 1a and respective kinetic energy difference D of cylinder 1c, 1d_ac、D_ad。

Then, in step S332, determination unit 632 is according to the calculated current cylinder of kinetic energy difference computing unit 631 and its The respective kinetic energy difference E of his cylinder_ab、E_ac、E_ad, maximum kinetic energy difference be determined as to catch fire judge parameter.In this example, such as when The kinetic energy difference E of front air cylinder 1a and cylinder 1c_acValue it is maximum, then by E_acIt is determined as to catch fire and judges parameter.

Fig. 3 is returned to, in step S34, filtering parameter computing unit 64 is calculated according to current data and history filtering data Current filter data.

Specifically, filtering parameter computing unit 64 calculates current filter data according to formula (2),

Y (t)=wy (t)+(1-w) Y (t-1) formula (2)

Wherein, Y (t) indicates the current filter data in time t, and y (t) indicates what detonation sensor 5 was detected in time t Current data, w are filter weights, and Y (t-1) indicates history filtering data, are the filtering data in time t-1, history filtering Number Y (t-1) is stored in the memory that figure does not regard.

Then, in step S35, parameter E is judged when catching fire_acMore than or equal to first threshold and current filter data Y (t) is less than When second threshold, the judging unit 65 that catches fire judges that current cylinder 1a catches fire.Parameter E is judged when catching fire_acMore than or equal to first threshold And current filter data Y (t) be more than or equal to second threshold when, the judging unit 65 that catches fire judges it is currently bumpy road.Here, One threshold value and second threshold are according to the predetermined threshold value of experimental data.

Fig. 6 is the effect explanatory diagram of the fire detecting method of engine according to an embodiment of the present invention.As shown in fig. 6, this Invention can accurately detect catching fire in the time 1.27,1.29,1.31.

Fig. 7 is another effect explanatory diagram of the fire detecting method of engine according to an embodiment of the present invention.Wherein, more A closed square indicates above-mentioned first threshold, and multiple solid diamond blocks indicate to judge parameter in catching fire for different time.Such as Fig. 7 institute Show, in dashed circle 70, catching fire for time 1.40 judges that parameter 71b, catching fire for time 1.42 judge parameter 71a, time 1.43 catch fire judges that parameter 71c is greater than first threshold, in addition, current filter data Y (1.40), the Y of corresponding time (1.42), Y (1.43) is also both less than second threshold.Therefore, the present invention can accurately detect time 1.40,1.42, 1.43 catch fire.

It is poor by calculating current cylinder 1a and the respective kinetic energy of other cylinders 1b, 1c, 1d in the present invention, and will be maximum Kinetic energy difference judges parameter as catching fire to carry out judgement of catching fire, and can catch fire simultaneously to avoid two cylinders of comparison causes to be difficult to sentence Disconnected situation.

In addition, due to the judgement of traditional bumpy road be also based on crankshaft sensor 4 by calculate cylinder between when Between difference realize, therefore when the case where continuous three cylinder catches fire occurs, catch fire and judge that parameter E can trigger bumpy road judgement and patrol Volume, so as to lead to be mistaken for bumpy road, and fail to correctly judge to catch fire.In the present invention, volume production engine is utilized On detonation sensor 5 detect current data y (t) and above-mentioned history filtering data Y (t-1), according to above-mentioned formula (2) count It the current filter data Y (t) of calculating and catches fire and judges parameter E, can accurately judge whether be currently bumpy road, To avoid the occurrence of erroneous judgement.

Although by being described in conjunction with specific embodiments to the present invention, for the ordinary artisan of this field, It will be apparent according to many substitutions, modification and the variation made after mentioned above.Therefore, when such substitution, modification When being fallen into variation within the spirit and scope of appended claims, it should be included in the present invention.