阅读说明：本技术 发动机超级爆震后处理方法及系统 (Engine super-detonation post-processing method and system ) 是由 秦龙 岳永召 雷言言 王恺 崔良浩 于 2021-07-22 设计创作，主要内容包括：本发明涉及发动机控制领域,尤其涉及发动机超级爆震后处理方法及系统。通过循序渐进的采用喷油加浓控制、气量减少控制、断油指令控制进行发动机超级爆震后处理,可针对不同程度的超级爆震采取针对性的控制措施,能够准确有效的控制发动机超级爆震现象；通过对超级爆震后处理气量减少控制和超级爆震后处理断油指令控制的相关系数进行自学习更新,能够快速、及时地对发动机超级爆震进行响应,有效保护发动机不被损坏；不仅分析判断了超级爆震异常燃烧连续发生的次数、对应气缸及对应工况,还分析判断了超级爆震未异常燃烧的连续燃烧次数、对应气缸及对应工况,使超级爆震后处理的效果更加精确,且能够保证车辆的动力性和平顺性。(The invention relates to the field of engine control, in particular to a super-knock post-processing method and a super-knock post-processing system for an engine. The super detonation aftertreatment of the engine is carried out by adopting oil injection enrichment control, air quantity reduction control and fuel cut-off instruction control step by step, and specific control measures can be taken aiming at super detonations of different degrees, so that the super detonation phenomenon of the engine can be accurately and effectively controlled; by self-learning updating of correlation coefficients of super-detonation post-treatment air quantity reduction control and super-detonation post-treatment fuel cut-off instruction control, super-detonation of the engine can be responded quickly and timely, and the engine is effectively protected from being damaged; the method has the advantages that the number of continuous occurrence of super-knock abnormal combustion, the corresponding cylinder and the corresponding working condition are analyzed and judged, the number of continuous combustion of super-knock non-abnormal combustion, the corresponding cylinder and the corresponding working condition are also analyzed and judged, so that the super-knock post-processing effect is more accurate, and the dynamic property and the smoothness of a vehicle can be ensured.)

1. An engine super-detonation post-processing method is characterized by comprising the following steps:

detecting super knock signals of each cylinder of the engine in real time, and carrying out corresponding processing strategies;

the processing strategy comprises the following steps:

A. when the super knocking continuously occurs in any cylinder and exceeds a first preset number of times, carrying out super knocking post-treatment oil injection enrichment control, and when the super knocking continuously occurs in any cylinder and does not exceed the first preset number of times and the duration time exceeds T0, gradually quitting the super knocking post-treatment oil injection enrichment control;

B. when the condition that the number of times of continuous super detonation in any cylinder exceeds a second preset number is detected, under the premise of super detonation post-treatment oil injection enrichment control, performing super detonation post-treatment air quantity reduction control until the target air quantity with reduced air quantity is reached, performing self-learning updating of the target air quantity with reduced air quantity and the second preset number, and gradually quitting the super detonation post-treatment air quantity reduction control when the number of times of continuous super detonation in any cylinder does not exceed the second preset number and the duration time exceeds T1;

C. when the engine load is within a preset range after the super knocking continuously occurs in any cylinder, the super knocking post-processing fuel cut-off instruction control is carried out on the premise of the super knocking post-processing gas amount reduction control, the third preset number of self-learning updating is carried out, and when the super knocking continuously occurs in any cylinder, the number of times does not exceed the third preset number of times and the duration time exceeds T2, the super knocking post-processing fuel cut-off instruction control is quitted.

2. The engine super-knock post-treatment method according to claim 1, comprising the following steps:

s1, detecting super knock signals of each cylinder of the engine in real time, performing super knock post-treatment oil injection enrichment control when detecting that super knock continuously occurs in any cylinder exceeds a first preset number, and gradually quitting the super knock post-treatment oil injection enrichment control when detecting that the number of continuously occurring super knock in any cylinder does not exceed the first preset number and the duration exceeds T0;

s2, detecting super knock signals of each cylinder of the engine in real time, when detecting that super knock continuously occurs in any cylinder and exceeds a second preset number of times, performing super knock post-treatment air quantity reduction control until reaching a target air quantity with reduced air quantity on the premise of super knock post-treatment oil injection enrichment control, and gradually quitting the super knock post-treatment air quantity reduction control when detecting that the number of continuously occurring super knock in any cylinder does not exceed the second preset number of times and the duration time exceeds T1;

s3, carrying out self-learning updating of the target gas quantity with reduced gas quantity, specifically, after carrying out super knock post-treatment gas quantity reduction control, when super knock continues to occur in any cylinder, identifying the working condition when super knock occurs, and reducing the target gas quantity with reduced gas quantity by preset target gas quantity variable quantity when the engine reaches the working condition when super knock occurs in the next working cycle;

s4, performing second preset number self-learning updating, specifically, after super-knock post-treatment gas amount reduction control is performed, when super-knock continues to occur in all working conditions of any cylinder, reducing the second preset number of corresponding cylinders in the next working cycle by 1, and when super-knock does not occur in all working conditions of all cylinders and the duration exceeds T3, increasing the second preset number of all cylinders in the next working cycle by 1;

s5, detecting super detonation signals of each cylinder of the engine in real time, performing super detonation post-processing fuel cut-off instruction control on the premise of super detonation post-processing air volume reduction control when super detonation is detected to occur continuously for more than a third preset number of times in any cylinder and the engine load is in a preset range, and quitting the super detonation post-processing fuel cut-off instruction control when the number of times of super detonation continuously occurring in any cylinder is detected to not exceed the third preset number of times and the duration time exceeds T2;

and S6, carrying out third preset number self-learning updating, specifically, after super knock postprocessing fuel cut-off instruction control is carried out, when super knock continues to occur in any cylinder, identifying a working condition when super knock occurs, when the engine reaches the working condition when super knock occurs in the next working cycle, reducing the third preset number of corresponding cylinders by 2 times, reducing the third preset number of next ignition cylinders by 1 time, and when super knock does not occur in all working conditions of all cylinders and the duration exceeds T4, increasing the third preset number of all cylinders in the next working cycle by 1 time.

3. The engine super-knock aftertreatment method according to claim 1 or 2, wherein: the super detonation post-treatment oil injection enrichment control specifically comprises that under the premise of keeping the air inflow unchanged, the fuel oil enrichment coefficient is directly improved to 1.25 times of the original working condition, and the fuel oil/air mixed gas of the next working cycle in all cylinders is enriched to reduce the temperature in the cylinders; the gradual quitting super knocking post-treatment oil injection enrichment control is specifically that the fuel oil enrichment coefficient is gradually reduced to an original working condition and a parameter allowable value according to a preset change rate, wherein the preset change rate depends on the rotating speed of the engine.

4. The engine super-knock aftertreatment method according to claim 1 or 2, wherein: the super-knocking post-treatment air volume reduction control specifically reduces the air volume of the next working cycle in all cylinders according to the air volume reduction change rate until reaching the target air volume of air volume reduction, wherein the target air volume of air volume reduction is related to the real-time engine rotating speed; and gradually quitting the super-knock post-treatment air volume reduction control, specifically gradually recovering the air volumes in all the cylinders to the preset working condition and parameter allowable values according to the air volume recovery change rate.

5. The engine super-knock aftertreatment method of claim 4, wherein: when the sum of the times of all the fuel cut instructions of each cylinder does not exceed the preset times of the fuel cut instructions, the gas quantity reduction change rate is-A, the gas quantity recovery change rate is B, and the target gas quantity of gas quantity reduction is C when the engine rotating speed is n; when the sum of the times of all the fuel cut instructions of each cylinder exceeds the preset times of the fuel cut instructions, the gas quantity reduction change rate is-D, the gas quantity recovery change rate is E, and the target gas quantity of gas quantity reduction is F when the engine rotating speed is n; a is more than D, B is less than E, C is less than F, A is more than B, and D is more than E.

6. The engine super-knock aftertreatment method according to claim 1 or 2, wherein: the super-detonation post-processing fuel-cut instruction control specifically comprises the steps of independently sending fuel-cut instructions to corresponding cylinders which continuously generate super-detonation, executing fuel-cut control, and reading the total fuel-cut times of each cylinder, the continuous fuel-cut times of each cylinder and the continuous combustion times of each cylinder without fuel cut in real time, wherein when the sum of the continuous fuel-cut times of each cylinder exceeds the preset total fuel-cut times, fuel-cut is not allowed even if the fuel-cut instructions are sent; and the step of quitting the super-detonation post-processing fuel cut-off instruction control specifically comprises the step of forbidding fuel cut-off of the current corresponding cylinder and not sending a fuel cut-off instruction any more.

7. The engine super-knock aftertreatment method according to claim 1 or 2, wherein: the first preset time is less than the second preset time and less than the third preset time, and the T0 is less than the T1 and less than the T2.

8. The engine super-knock aftertreatment method of claim 2, wherein: the working condition specifically refers to the rotating speed, load, water temperature and VVT angle of the engine, and the preset target air quantity variable quantity is equal toBasic value of target air quantity variation x multiplication factor, wherein the multiplication factor depends on time interval delta T between two adjacent super-knock occurrences₂And Δ T₂The average value n of the engine speed.

9. An engine super-detonation aftertreatment system, comprising:

the super knock sensor is used for detecting super knock signals of all cylinders of the engine in real time;

the sensor signal processing module is used for processing the super knock signal and identifying super knock intensity;

and the engine controller is used for detecting and analyzing the processed knock signal in real time on line, and judging the continuous occurrence frequency of abnormal combustion of super knock, the corresponding cylinder and the corresponding working condition as well as the continuous combustion frequency of non-abnormal combustion of super knock, the corresponding cylinder and the corresponding working condition.

10. The engine super-knock aftertreatment system of claim 9, wherein: the engine controller runs a super-detonation aftertreatment control program, and the engine controller executes the program to realize the steps of the method according to the claims 1-8; the working conditions specifically refer to the rotating speed, load, water temperature and VVT angle of the engine.

Technical Field

The invention relates to the field of engine control, in particular to a super-knock post-processing method and a super-knock post-processing system for an engine.

Background

The oil engine supercharging technology is one of the advanced gasoline engine technologies widely applied in the automobile industry at home and abroad, and is the mainstream technology for realizing the miniaturization and low speed of the gasoline engine, greatly improving the power performance of the gasoline engine and reducing the oil consumption. However, after the technology is applied, when the gasoline engine can output higher torque and power, the peak value of the explosion pressure and the peak value of the combustion temperature in the cylinder are also obviously increased, and the self-ignition of fuel/air mixture, namely pre-ignition, is very easy to occur before the ignition of a spark plug, and is called super detonation in the industry.

Super detonation combustion of the gasoline engine is an abnormal combustion phenomenon, has strong randomness, is mostly generated in low-speed and high-load working conditions of the gasoline engine, and is very easy to cause serious mechanical faults of the gasoline engine such as piston collapse and the like along with ultrahigh peak pressure in a cylinder and extremely high pressure oscillation frequency, so that the gasoline engine fails to work. The super detonation abnormal combustion has strong randomness, and the initiation reason is mainly the thermal environment in the cylinder, so that the complete elimination of the super detonation abnormal combustion of the supercharged gasoline engine becomes an industry-recognized technical problem, and the occurrence frequency of the super detonation abnormal combustion can be only controlled so as to avoid the damage of the engine under the condition of the overhigh super detonation combustion frequency.

The existing super-detonation treatment control method does not consider the dynamic influence of the real-time working condition of the engine and the aging of parts on the super-detonation, and has the phenomena of untimely super-detonation treatment and excessive or insufficient treatment degree, so that the dynamic property, the economical efficiency and the emission of the engine are poor, and the engine is easy to damage.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the super detonation post-processing method and the super detonation post-processing system for the engine can accurately and effectively control the super detonation phenomenon of the engine, have high response speed, ensure the smoothness of the torque of the engine and protect the engine from being damaged.

In order to solve the technical problems, the invention adopts the technical scheme that:

an engine super-detonation post-processing method is characterized by comprising the following steps:

detecting super knock signals of each cylinder of the engine in real time, and carrying out corresponding processing strategies;

the processing strategy comprises the following steps:

A. when the super knocking continuously occurs in any cylinder and exceeds a first preset number of times, carrying out super knocking post-treatment oil injection enrichment control, and when the super knocking continuously occurs in any cylinder and does not exceed the first preset number of times and the duration time exceeds T0, gradually quitting the super knocking post-treatment oil injection enrichment control;

B. when the condition that the number of times of continuous super detonation in any cylinder exceeds a second preset number is detected, under the premise of super detonation post-treatment oil injection enrichment control, performing super detonation post-treatment air quantity reduction control until the target air quantity with reduced air quantity is reached, performing self-learning updating of the target air quantity with reduced air quantity and the second preset number, and gradually quitting the super detonation post-treatment air quantity reduction control when the number of times of continuous super detonation in any cylinder does not exceed the second preset number and the duration time exceeds T1;

C. when the engine load is within a preset range after the super knocking continuously occurs in any cylinder, the super knocking post-processing fuel cut-off instruction control is carried out on the premise of the super knocking post-processing gas amount reduction control, the third preset number of self-learning updating is carried out, and when the super knocking continuously occurs in any cylinder, the number of times does not exceed the third preset number of times and the duration time exceeds T2, the super knocking post-processing fuel cut-off instruction control is quitted.

Further, the engine super-knock post-processing method specifically comprises the following steps:

s1, detecting super knock signals of each cylinder of the engine in real time, performing super knock post-treatment oil injection enrichment control when detecting that super knock continuously occurs in any cylinder exceeds a first preset number, and gradually quitting the super knock post-treatment oil injection enrichment control when detecting that the number of continuously occurring super knock in any cylinder does not exceed the first preset number and the duration exceeds T0;

s2, detecting super knock signals of each cylinder of the engine in real time, when detecting that super knock continuously occurs in any cylinder and exceeds a second preset number of times, performing super knock post-treatment air quantity reduction control until reaching a target air quantity with reduced air quantity on the premise of super knock post-treatment oil injection enrichment control, and gradually quitting the super knock post-treatment air quantity reduction control when detecting that the number of continuously occurring super knock in any cylinder does not exceed the second preset number of times and the duration time exceeds T1;

s3, carrying out self-learning updating of the target gas quantity with reduced gas quantity, specifically, after carrying out super knock post-treatment gas quantity reduction control, when super knock continues to occur in any cylinder, identifying the working condition when super knock occurs, and reducing the target gas quantity with reduced gas quantity by preset target gas quantity variable quantity when the engine reaches the working condition when super knock occurs in the next working cycle;

s4, performing second preset number self-learning updating, specifically, after super-knock post-treatment gas amount reduction control is performed, when super-knock continues to occur in all working conditions of any cylinder, reducing the second preset number of corresponding cylinders in the next working cycle by 1, and when super-knock does not occur in all working conditions of all cylinders and the duration exceeds T3, increasing the second preset number of all cylinders in the next working cycle by 1;

s5, detecting super detonation signals of each cylinder of the engine in real time, performing super detonation post-processing fuel cut-off instruction control on the premise of super detonation post-processing air volume reduction control when super detonation is detected to occur continuously for more than a third preset number of times in any cylinder and the engine load is in a preset range, and quitting the super detonation post-processing fuel cut-off instruction control when the number of times of super detonation continuously occurring in any cylinder is detected to not exceed the third preset number of times and the duration time exceeds T2;

and S6, carrying out third preset number self-learning updating, specifically, after super knock postprocessing fuel cut-off instruction control is carried out, when super knock continues to occur in any cylinder, identifying a working condition when super knock occurs, when the engine reaches the working condition when super knock occurs in the next working cycle, reducing the third preset number of corresponding cylinders by 2 times, reducing the third preset number of next ignition cylinders by 1 time, and when super knock does not occur in all working conditions of all cylinders and the duration exceeds T4, increasing the third preset number of all cylinders in the next working cycle by 1 time.

Further, the super-detonation post-treatment oil injection enrichment control specifically includes that on the premise that air inflow is kept unchanged, the fuel oil enrichment coefficient is directly improved to be 1.25 times of the original working condition, and fuel oil/air mixed gas of the next working cycle in all cylinders is enriched to reduce the temperature in the cylinders; the gradual quitting super knocking post-treatment oil injection enrichment control is specifically that the fuel oil enrichment coefficient is gradually reduced to an original working condition and a parameter allowable value according to a preset change rate, wherein the preset change rate depends on the rotating speed of the engine.

Further, the super-knock post-treatment air volume reduction control specifically reduces the air volume of the next working cycle in all cylinders according to the air volume reduction change rate until reaching the target air volume of air volume reduction, wherein the target air volume of air volume reduction is related to the real-time engine rotating speed; and gradually quitting the super-knock post-treatment air volume reduction control, specifically gradually recovering the air volumes in all the cylinders to the preset working condition and parameter allowable values according to the air volume recovery change rate.

Further, when the sum of the times of all fuel cut instructions of each cylinder does not exceed the preset times of fuel cut instructions, the gas quantity reduction change rate is-A, the gas quantity recovery change rate is B, and the target gas quantity of gas quantity reduction is C when the engine speed is n; when the sum of the times of all the fuel cut instructions of each cylinder exceeds the preset times of the fuel cut instructions, the gas quantity reduction change rate is-D, the gas quantity recovery change rate is E, and the target gas quantity of gas quantity reduction is F when the engine rotating speed is n; a is more than D, B is less than E, C is less than F, A is more than B, and D is more than E.

Further, the super-knocking post-processing fuel cut instruction control specifically includes that fuel cut instructions are sent to corresponding cylinders which continuously generate super-knocking independently, fuel cut control is executed, the total fuel cut times of each cylinder, the continuous fuel cut times of each cylinder and the continuous combustion times of each cylinder without fuel cut are read in real time, and when the sum of the continuous fuel cut times of each cylinder exceeds the preset total fuel cut times, fuel cut is not allowed any more even if the fuel cut instructions are sent; and the step of quitting the super-detonation post-processing fuel cut-off instruction control specifically comprises the step of forbidding fuel cut-off of the current corresponding cylinder and not sending a fuel cut-off instruction any more.

Furthermore, the first preset time is less than the second preset time and less than the third preset time, and the T0 is less than the T1 and less than the T2.

Further, the operating conditions specifically refer to the rotation speed, load, water temperature and VVT angle of the engine, the preset target air quantity variation is a target air quantity variation basic value multiplied by a multiplication factor, and the multiplication factor depends on the time interval Δ T between two adjacent super-knock occurrences₂And Δ T₂The average value n of the engine speed.

An engine super-detonation aftertreatment system, comprising:

the super knock sensor is used for detecting super knock signals of all cylinders of the engine in real time;

the sensor signal processing module is used for processing the super knock signal and identifying super knock intensity;

and the engine controller is used for detecting and analyzing the processed knock signal in real time on line, and judging the continuous occurrence frequency of abnormal combustion of super knock, the corresponding cylinder and the corresponding working condition as well as the continuous combustion frequency of non-abnormal combustion of super knock, the corresponding cylinder and the corresponding working condition.

Further, the engine controller runs a super knock post-processing control program, and the engine controller executes the program to realize the steps of the method according to the claims 1-8; the working conditions specifically refer to the rotating speed, load, water temperature and VVT angle of the engine.

Compared with the prior art, the invention has the following main advantages:

1. the super detonation aftertreatment of the engine is carried out by adopting oil injection enrichment control, air quantity reduction control and fuel cut-off instruction control step by step, and specific control measures can be taken aiming at super detonations of different degrees, so that the super detonation phenomenon of the engine can be accurately and effectively controlled;

2. by self-learning updating of correlation coefficients of super-detonation post-treatment air quantity reduction control and super-detonation post-treatment fuel cut-off instruction control, super-detonation of the engine can be responded quickly and timely, and the engine is effectively protected from being damaged;

3. the target air quantity reduced by optimizing the air quantity is updated by combining with the real-time working condition of the engine, so that the influence of super-knock post-treatment on the dynamic property of the vehicle can be reduced on the premise of inhibiting super-knock, the fluctuation of the torque of the engine can be reduced, and the flameout of the engine can be avoided;

4. the method has the advantages that the number of continuous occurrence of super-knock abnormal combustion, the corresponding cylinder and the corresponding working condition are analyzed and judged, the number of continuous combustion of super-knock non-abnormal combustion, the corresponding cylinder and the corresponding working condition are also analyzed and judged, so that the super-knock post-processing effect is more accurate, and the dynamic property and the smoothness of a vehicle can be ensured.

Drawings

FIG. 1 is a logic diagram of a super-detonation post-processing method for an engine according to the present invention;

FIG. 2 is a schematic diagram of an engine super-detonation aftertreatment system of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to fig. 1 and an embodiment. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

It should be noted that, according to the implementation requirement, each step/component described in the present application can be divided into more steps/components, and two or more steps/components or partial operations of the steps/components can be combined into new steps/components to achieve the purpose of the present invention.

First embodiment, an engine super-knock post-processing method implemented according to the present invention is shown in fig. 1, and specifically includes the following steps:

s1, detecting super knock signals of each cylinder of the engine in real time, and performing super knock post-treatment oil injection enrichment control when detecting that the super knock continuously occurs in any cylinder exceeds a first preset number (1 in the example); and gradually quitting the super-knock post-treatment fuel injection enrichment control when the conditions that the number of times of continuously generating super-knock in any cylinder does not exceed the first preset number (1 time in the example) and the duration time exceeds T0 (0.25 s in the example) are detected.

The super-detonation post-treatment oil injection enrichment control specifically comprises the steps of increasing the fuel enrichment coefficient to be 1.25 times of the original working condition on the premise of keeping the air inflow unchanged, and enriching the fuel/air mixed gas of the next working cycle in all cylinders so as to reduce the temperature in the cylinders.

The gradual quitting super-knock post-treatment oil injection enrichment control is characterized in that a fuel oil enrichment coefficient is gradually reduced to an original working condition and a parameter allowable value according to a preset change rate, the preset change rate depends on the rotating speed of an engine, and the specific relation is as follows:

when super detonation post-treatment oil injection enrichment control is carried out, the fuel oil enrichment coefficient is directly and quickly improved, super detonation can be quickly responded, and an engine is protected; when the super detonation post-processing oil injection enrichment control is quitted, the fuel oil enrichment factor is gradually reduced at a slow speed, so that the super detonation can be prevented from being recovered again due to the fact that the fuel oil enrichment factor is reduced too fast.

S2, detecting super knock signals of each cylinder of the engine in real time, and when detecting that super knock continuously occurs in any cylinder and exceeds a second preset number (the initial value of the example is 3 times), performing super knock post-treatment air quantity reduction control on the premise of super knock post-treatment oil injection enrichment control; when it is detected that the number of continuous super-knocking occurrences in any cylinder does not exceed the second preset number (the initial value of the present example is 3) and the duration exceeds T1 (0.6 s in the present example), the super-knocking post-treatment-air-quantity reduction control is gradually exited.

The super-knock post-treatment air volume reduction control specifically includes reducing air volumes of next working cycle in all cylinders according to air volume reduction change rates until reaching target air volumes of air volume reduction, namely reducing the working load of an engine and the combustion temperature and pressure in the cylinders, wherein the target air volumes of air volume reduction are not less than the minimum air volumes for avoiding engine flameout under various working conditions, and the target air volumes of air volume reduction are related to the real-time engine rotating speed.

And gradually quitting the super-knock post-treatment air volume reduction control, specifically gradually recovering the air volumes in all the cylinders to the preset working condition and parameter allowable values according to the air volume recovery change rate.

1) When the sum of all the times of the fuel cut instruction of each cylinder does not exceed the preset times of the fuel cut instruction (3 is taken in the example), the gas amount reduction change rate is-200 mg/l/10ms in the example, the gas amount recovery change rate is 80mg/l/10ms in the example, and the relationship between the target gas amount of gas amount reduction and the real-time engine rotating speed is as follows:

2) when the sum of all the times of the fuel cut instruction of each cylinder exceeds the preset times of the fuel cut instruction (3 is taken in the example), the gas quantity reduction change rate is-100 mg/l/10ms, the gas quantity recovery change rate is 90mg/l/10ms, and the relationship between the target gas quantity of the gas quantity reduction and the real-time engine rotating speed is as follows:

the engine has the advantages that the number of times of fuel cut instructions of the engine under the second condition is large, the torque change is large, the air volume reduction under the second condition is relatively less than that under the first condition, the torque fluctuation is avoided to be large, and the large air volume can quickly respond to the torque response after the oil supply is recovered next time.

Furthermore, the reason why the target air quantity of air quantity reduction is related to the real-time engine rotating speed is that under the premise of achieving super knock suppression, the influence on the vehicle dynamic performance is ensured to be small under different rotating speeds, and the torque fluctuation change rate is not more than +/-5 Nm/100 ms.

Furthermore, the absolute value of the air quantity reduction change rate is large, so that super knocking can be quickly dealt with, and an engine can be protected; the absolute value of the gas quantity recovery change rate is small, so that super knock can be prevented from recovering again due to fast gas quantity recovery.

S3, performing self-learning updating of the target gas quantity with reduced gas quantity, specifically, after performing super knock post-treatment gas quantity reduction control, when super knock continues to occur in any cylinder, recognizing the working condition when super knock occurs, and further reducing the target gas quantity with reduced gas quantity when the engine reaches the working condition when super knock occurs in the next working cycle (the purpose of gradually reducing the target gas quantity is to avoid vehicle suspension caused by large interference of gas quantity fluctuation on rotating speed and torque), but the gas quantity must not be less than the minimum gas quantity allowed in each working condition (the allowed minimum gas quantity refers to the minimum gas quantity of the engine capable of not extinguishing fire).

Wherein, the target gas amount variation is the basic value of the target gas amount variation (in this example, 35mg/l) × multiplication factorWherein n is the time interval Delta T between two adjacent super-knock occurrences₂Average value of engine speed in, said multiplication factorAndthe relationship of (A) to (B) is as follows:

the idea of calibrating the settings is: if the time of two adjacent times is shorter, the air quantity needs to be reduced as soon as possible to suppress the occurrence of knocking. By usingThe reasons for this are: the super detonation is caused by abnormal combustion of each cylinder, each cylinder finishes once acting every 2 times when the engine rotates, and the super detonation is easier to occur near the acting stroke, so that the continuous occurrence of the super detonation can be avoided and the loss of torque can be reduced as much as possible by directly adopting the interval time based on the number of running circles of the engine as an input ratio.

S4, performing second preset times of self-learning updating, specifically, after super-knock post-treatment air quantity reduction control is performed, when super-knock continues to occur under all working conditions of any cylinder, reducing the second preset times of the corresponding cylinder in the next working cycle by 1 time; when super knock is not present in all cylinders under all operating conditions and the duration exceeds T3 (example 20s), then the second preset number of times for all cylinders in the next operating cycle is increased by 1.

The working conditions specifically refer to the rotation speed, load, water temperature and VVT (variable valve timing) angle of the engine.

S5, detecting super knock signals of each cylinder of the engine in real time, and when detecting that the super knock continuously occurs in any cylinder for more than a third preset number of times (the initial value of the example is 5 times) and the load of the engine is in a preset range, performing super knock post-processing fuel cut instruction control on the premise of controlling reduction of super knock post-processing air quantity; and when the super knocking continuously occurs in any cylinder and the number of times does not exceed the third preset number (the initial value of the example is 5 times) and the duration time exceeds T2 (the example 1s), quitting the super knocking post-processing fuel cut instruction control.

The load of the engine depends on the rotating speed of the engine, when the load is too high, protection after super detonation is realized without oil cut, and the influence of oil cut on the dynamic property is poor by reducing the air quantity; when the load is too low, the engine is not controlled by a fuel cut-off instruction, and the engine is prevented from stalling, wherein the relationship between the engine load and the real-time engine rotating speed is as follows:

the super-detonation post-processing fuel-cut instruction control specifically comprises the steps of sending fuel-cut instructions to corresponding cylinders which continuously generate super-detonation, executing fuel-cut control, and reading the total fuel-cut times of each cylinder, the continuous fuel-cut times of each cylinder and the continuous combustion times of each cylinder which does not generate fuel-cut in real time, wherein when the sum of the continuous fuel-cut times of each cylinder exceeds the preset total fuel-cut times (10 is taken in the example), fuel-cut instructions are not allowed to be sent any more even if the fuel-cut instructions are sent, so that the vehicle irregularity caused by the influence on dynamic property is avoided.

And the step of quitting the super-detonation post-processing fuel cut-off instruction control specifically comprises the step of forbidding fuel cut-off of the current corresponding cylinder and not sending a fuel cut-off instruction any more.

S6, carrying out self-learning update for a third preset time, specifically, after carrying out super knock post-processing fuel cut-off instruction control, when super knock continues to occur in any cylinder, the operating condition at which super knock occurs is identified and, at the next operating cycle when the engine reaches said operating condition at which super knock occurs, the third preset number of times of the corresponding cylinder is reduced by 2 times, and the third preset number of times of the next ignition cylinder after the corresponding cylinder is reduced by 1 time (in this example, a 4-cylinder machine is adopted, the working cycle is 1-3-2-4, namely, the 3 rd cylinder starts to work after the 1 st cylinder works, and then the 2 nd cylinder and the 4 th cylinder are adopted, so that the next ignition cylinder is 4 cylinders under the assumption that the current corresponding cylinder is 2 cylinders, wherein the reason for reducing the third preset number of times of the next ignition cylinder is set is that the combustion stability of the current engine can influence the next ignition cylinder); when super knock is not present in all cylinders under all operating conditions and the duration exceeds T4 (example 25s), then the third preset number of times for all cylinders in the next operating cycle is increased by 1.

The working conditions specifically refer to the rotation speed, load, water temperature and VVT (variable valve timing) angle of the engine.

The first preset time is less than the second preset time and less than the third preset time, and the T0 is less than the T1 and less than the T2.

The method is suitable for automobiles of pure engine type and hybrid vehicle type containing the engine.

Based on the same inventive concept, the embodiment of the present application further provides an engine super-knock aftertreatment system, as shown in fig. 2, including:

the super knock sensor is used for detecting super knock signals of all cylinders of the engine in real time;

the sensor signal processing module is used for processing the super knock signal and identifying super knock intensity;

and the engine controller is used for detecting and analyzing the processed knock signal in real time on line, and judging the continuous occurrence frequency of abnormal combustion of super knock, the corresponding cylinder and the corresponding working condition as well as the continuous combustion frequency of non-abnormal combustion of super knock, the corresponding cylinder and the corresponding working condition.

The operating conditions specifically refer to the engine speed, load, water temperature, and VVT (variable valve timing) angle.

The engine controller runs a super-knock aftertreatment control program, and when the engine controller executes the program, all or part of the method steps of the method are realized.

The second embodiment is basically the same as the first embodiment in principle and technical scheme, and the difference is as follows: and if the super detonation is not detected or the super detonation post-processing method is completely exited, the engine controller operates according to the original working condition and parameter setting.

The third embodiment is basically the same as the first and second embodiments in principle and technical scheme, and the difference is as follows: when the sum of the continuous fuel cut-off times of each cylinder exceeds the preset total fuel cut-off times (10 in the example), fuel cut-off is not allowed even if a fuel cut-off command is sent, at the moment, the fuel cut-off command exceeding the preset total fuel cut-off times does not respond to the cylinder number which is distributed to the cylinder number with the largest continuous combustion times and has no fuel cut-off, namely, the cylinder number with the largest continuous combustion times and has no fuel cut-off is firstly recovered to supply fuel, the cylinder number with the second continuous combustion times and has no fuel cut-off is recovered to supply fuel, and the like.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.