阅读说明：本技术 一种燃气发动机控制方法及装置 (Gas engine control method and device ) 是由 曹石 秦涛 孙松友 贾晓峰 于 2021-09-29 设计创作，主要内容包括：本发明提供的燃气发动机控制方法及装置,应用于发动机技术领域,该方法在获取表征燃气发动机运行状态的目标参数后,如果目标参数满足预设控制条件,则获取当前氧闭环控制修正因数和当前氧闭环控制学习因数,并根据当前氧闭环控制修正因数和当前氧闭环控制学习因数,判断燃气发动机是否满足预设修正条件,如果燃气发动机满足预设修正条件,则根据当前氧闭环控制学习因数修正燃气发动机的需求空气充量和需求EGR率。与现有技术相比,本方案不再依赖报文传递燃料信息,因而可以适用于整车控制器与发动机控制器之间无法发送报文的车辆,解决发动机超功率、爆震、功率不足以及失火等问题。(The invention provides a gas engine control method and a device, which are applied to the technical field of engines. Compared with the prior art, the scheme does not rely on message transmission fuel information any more, so that the method and the device are suitable for vehicles which cannot send messages between a vehicle control unit and an engine controller, and solve the problems of over power, knocking, insufficient power, fire and the like of the engine.)

1. A gas engine control method characterized by comprising:

acquiring target parameters representing the running state of the gas engine;

if the target parameter meets a preset control condition, acquiring a current oxygen closed-loop control correction factor, a current oxygen closed-loop control learning factor and a current engine speed;

judging whether the gas engine meets a preset correction condition or not according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor;

and if the gas engine meets the preset correction condition, correcting the required air charge and the required EGR rate of the gas engine according to the current oxygen closed-loop control learning factor and the current engine rotating speed.

2. The gas engine control method according to claim 1, wherein said determining whether the gas engine satisfies a preset correction condition according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor comprises:

if the current oxygen closed-loop control correction factor is greater than or equal to a first preset factor threshold and the current oxygen closed-loop control learning factor is greater than or equal to a second preset factor threshold,

or, the current oxygen closed-loop control correction factor is less than or equal to a third preset factor threshold value and the current oxygen closed-loop control learning factor is less than or equal to a fourth preset factor threshold value, and the gas engine is judged to meet a preset correction condition;

if the current oxygen closed-loop control correction factor is less than the first predetermined factor threshold,

or, the current oxygen closed-loop control learning factor is smaller than the second preset factor threshold,

or, the current oxygen closed-loop control correction factor is larger than the third preset factor threshold,

or, the current oxygen closed-loop control learning factor is larger than the fourth preset factor threshold value, and the gas engine is judged not to meet the preset correction condition;

the first preset factor threshold is greater than the third preset factor threshold, and the second preset factor threshold is greater than the fourth preset factor threshold.

3. The gas engine control method of claim 2, wherein said correcting the demanded air charge and the demanded EGR rate of the gas engine based on the current oxygen closed-loop control learning factor and the current engine speed comprises:

under the condition that the current oxygen closed-loop control correction factor is greater than or equal to a first preset factor threshold value and the current oxygen closed-loop control learning factor is greater than or equal to a second preset factor threshold value, increasing the required air charge of the gas engine according to the current oxygen closed-loop control learning factor and the current engine speed, and reducing the required EGR rate of the gas engine;

and under the condition that the current oxygen closed-loop control correction factor is smaller than or equal to a third preset factor threshold value and the current oxygen closed-loop control learning factor is smaller than or equal to a fourth preset factor threshold value, reducing the required air charge of the gas engine according to the current oxygen closed-loop control learning factor and the current engine speed, and increasing the required EGR rate of the gas engine.

4. The gas engine control method of claim 3, wherein said increasing a required air charge of the gas engine and decreasing a required EGR rate of the gas engine based on the current oxygen closed loop control learning factor and the current engine speed comprises:

determining an air charge adjustment coefficient corresponding to the current oxygen closed-loop control learning factor and the current engine speed according to a first preset mapping relation to obtain a first air charge adjustment coefficient;

wherein, the first preset mapping relation records an oxygen closed-loop control learning factor and a corresponding relation between the engine speed and an air charge adjustment coefficient, and the air charge adjustment coefficient is increased along with the increase of the oxygen closed-loop control learning factor;

increasing a demanded air charge of the gas engine based on the first air charge adjustment coefficient;

determining an EGR rate adjustment coefficient corresponding to the current oxygen closed-loop control learning factor according to a second preset mapping relation to obtain a first EGR rate adjustment coefficient;

wherein, the second preset mapping relation records the corresponding relation between the oxygen closed-loop control learning factor and the EGR rate adjustment coefficient, and the EGR rate adjustment coefficient is reduced along with the increase of the oxygen closed-loop control learning factor;

reducing a required EGR rate of the gas engine based on the first EGR rate adjustment factor.

5. The gas engine control method of claim 3, wherein said reducing the required air charge of the gas engine and increasing the required EGR rate of the gas engine based on the current oxygen closed loop control learning factor and the current engine speed comprises:

determining an air charge adjustment coefficient corresponding to the current oxygen closed-loop control learning factor and the current engine speed according to a third preset mapping relation to obtain a second air charge adjustment coefficient;

wherein, the third preset mapping relation records an oxygen closed-loop control learning factor and a corresponding relation between the engine speed and an air charge adjustment coefficient, and the air charge adjustment coefficient is reduced along with the reduction of the oxygen closed-loop control learning factor;

reducing a required air charge of the gas engine based on the second air charge adjustment factor;

determining an EGR rate adjustment coefficient corresponding to the current oxygen closed-loop control learning factor according to a fourth preset mapping relation to obtain a second EGR rate adjustment coefficient;

wherein, the fourth preset mapping relation records the corresponding relation between the oxygen closed-loop control learning factor and the EGR rate adjustment coefficient, and the EGR rate adjustment coefficient is increased along with the reduction of the oxygen closed-loop control learning factor;

increasing a required EGR rate of the gas engine based on the second EGR rate adjustment factor.

6. The gas engine control method according to claim 1, wherein if the target parameter includes an engine speed, the preset control condition includes that the engine speed is greater than a preset speed threshold;

if the target parameter comprises natural gas rail pressure, the preset control condition comprises that the natural gas rail pressure is larger than a preset rail pressure threshold value;

if the target parameter comprises an oxygen closed-loop control function state, the preset control condition comprises that the oxygen closed-loop control function is in an enabling state;

if the target parameter comprises an oxygen closed-loop control correction factor self-learning function state, the preset control condition comprises that the oxygen closed-loop control correction factor self-learning function is in an enabling state;

and if the target parameter comprises the working state of the control valve related to the engine operation, the preset control condition comprises that the control valve related to the engine operation is in a normal state.

7. The gas engine control method according to any one of claims 1 to 6, characterized by further comprising:

and correcting the gas injection quantity of the gas engine according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor.

8. A gas engine control device characterized by comprising:

the first acquisition unit is used for acquiring target parameters representing the running state of the gas engine;

the second acquisition unit is used for acquiring a current oxygen closed-loop control correction factor, a current oxygen closed-loop control learning factor and a current engine speed if the target parameter meets a preset control condition;

the judging unit is used for judging whether the gas engine meets a preset correction condition or not according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor;

and the first correction unit is used for correcting the required air charge and the required EGR rate of the gas engine according to the current oxygen closed-loop control learning factor and the current engine rotating speed if the gas engine meets the preset correction condition.

9. The gas engine control device according to claim 8, wherein the determining unit is configured to determine whether the gas engine satisfies a preset correction condition according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor, and specifically includes:

if the current oxygen closed-loop control correction factor is greater than or equal to a first preset factor threshold and the current oxygen closed-loop control learning factor is greater than or equal to a second preset factor threshold,

or, the current oxygen closed-loop control correction factor is less than or equal to a third preset factor threshold value and the current oxygen closed-loop control learning factor is less than or equal to a fourth preset factor threshold value, and the gas engine is judged to meet a preset correction condition;

if the current oxygen closed-loop control correction factor is less than the first predetermined factor threshold,

or, the current oxygen closed-loop control learning factor is smaller than the second preset factor threshold,

or, the current oxygen closed-loop control correction factor is larger than the third preset factor threshold,

or, the current oxygen closed-loop control learning factor is larger than the fourth preset factor threshold value, and the gas engine is judged not to meet the preset correction condition;

the first preset factor threshold is greater than the third preset factor threshold, and the second preset factor threshold is greater than the fourth preset factor threshold.

10. The gas engine control device according to any one of claims 8 to 9, further comprising:

and the second correction unit is used for correcting the gas injection quantity of the gas engine according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor.

Technical Field

The invention belongs to the technical field of engines, and particularly relates to a gas engine control method and device.

Background

Because the gas quality components and the heat values of natural gas of different gas filling stations in the market are different, the gas filling of vehicles is accompanied with the change of natural gas performance parameters every time, if the gas engine is controlled to operate by the same control data, the problems of engine overpower, detonation and the like of the gas engine when high-heat-value natural gas is used can be caused, and the problems of engine power insufficiency, fire and the like of the gas engine when low-heat-value natural gas is used can be caused.

In practical application, most engine controllers have a natural gas self-adaptive control function, and adopt control processes corresponding to gas components of natural gas with different gas components. The premise of activating the natural gas self-adaptive control function is that the natural gas used by the gas engine can be accurately judged to be changed. In the prior art, a vehicle control unit acquires fuel information of a fuel tank through a sensor, such as gas pressure and gas liquid level, and sends the fuel information to an engine controller in the form of a message, and the engine controller judges whether a natural gas adaptive function needs to be activated according to the fuel information recorded in the message.

However, the inventor researches and discovers that at present, not all vehicles support communication between a vehicle controller and an engine controller in a message mode, so that fuel information cannot be transmitted to the engine controller, and therefore, a gas engine cannot necessarily judge whether a natural gas adaptive control function needs to be activated, and the problems of over power, knocking, insufficient power, fire and the like of the engine cannot be solved.

Disclosure of Invention

In view of the above, an object of the present invention is to provide a method and an apparatus for controlling a gas engine, which determine whether the gas engine meets a preset correction condition according to a current oxygen closed-loop control correction factor and a current oxygen closed-loop control learning factor, and correct a required air charge and a required EGR rate of the gas engine when the preset correction condition is met, and determine whether gas replacement occurs without depending on a message of a vehicle controller, so as to solve the problems in the prior art, and the specific scheme is as follows:

in a first aspect, the present invention provides a gas engine control method comprising:

acquiring target parameters representing the running state of the gas engine;

if the target parameter meets a preset control condition, acquiring a current oxygen closed-loop control correction factor, a current oxygen closed-loop control learning factor and a current engine speed;

judging whether the gas engine meets a preset correction condition or not according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor;

and if the gas engine meets the preset correction condition, correcting the required air charge and the required EGR rate of the gas engine according to the current oxygen closed-loop control learning factor and the current engine rotating speed.

Optionally, the determining whether the gas engine meets a preset correction condition according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor includes:

if the current oxygen closed-loop control correction factor is greater than or equal to a first preset factor threshold and the current oxygen closed-loop control learning factor is greater than or equal to a second preset factor threshold,

or, the current oxygen closed-loop control correction factor is less than or equal to a third preset factor threshold value and the current oxygen closed-loop control learning factor is less than or equal to a fourth preset factor threshold value, and the gas engine is judged to meet a preset correction condition;

if the current oxygen closed-loop control correction factor is less than the first predetermined factor threshold,

or, the current oxygen closed-loop control learning factor is smaller than the second preset factor threshold,

or, the current oxygen closed-loop control correction factor is larger than the third preset factor threshold,

or, the current oxygen closed-loop control learning factor is larger than the fourth preset factor threshold value, and the gas engine is judged not to meet the preset correction condition;

the first preset factor threshold is greater than the third preset factor threshold, and the second preset factor threshold is greater than the fourth preset factor threshold.

Optionally, the correcting the required air charge and the required EGR rate of the gas engine according to the current oxygen closed-loop control learning factor and the current engine speed comprises:

under the condition that the current oxygen closed-loop control correction factor is greater than or equal to a first preset factor threshold value and the current oxygen closed-loop control learning factor is greater than or equal to a second preset factor threshold value, increasing the required air charge of the gas engine according to the current oxygen closed-loop control learning factor and the current engine speed, and reducing the required EGR rate of the gas engine;

and under the condition that the current oxygen closed-loop control correction factor is smaller than or equal to a third preset factor threshold value and the current oxygen closed-loop control learning factor is smaller than or equal to a fourth preset factor threshold value, reducing the required air charge of the gas engine according to the current oxygen closed-loop control learning factor and the current engine speed, and increasing the required EGR rate of the gas engine.

Optionally, the increasing the required air charge of the gas engine and decreasing the required EGR rate of the gas engine according to the current oxygen closed-loop control learning factor and the current engine speed comprises:

determining an air charge adjustment coefficient corresponding to the current oxygen closed-loop control learning factor and the current engine speed according to a first preset mapping relation to obtain a first air charge adjustment coefficient;

wherein, the first preset mapping relation records an oxygen closed-loop control learning factor and a corresponding relation between the engine speed and an air charge adjustment coefficient, and the air charge adjustment coefficient is increased along with the increase of the oxygen closed-loop control learning factor;

increasing a demanded air charge of the gas engine based on the first air charge adjustment coefficient;

determining an EGR rate adjustment coefficient corresponding to the current oxygen closed-loop control learning factor according to a second preset mapping relation to obtain a first EGR rate adjustment coefficient;

wherein, the second preset mapping relation records the corresponding relation between the oxygen closed-loop control learning factor and the EGR rate adjustment coefficient, and the EGR rate adjustment coefficient is reduced along with the increase of the oxygen closed-loop control learning factor;

reducing a required EGR rate of the gas engine based on the first EGR rate adjustment factor.

Optionally, the reducing the required air charge of the gas engine and increasing the required EGR rate of the gas engine according to the current oxygen closed-loop control learning factor and the current engine speed comprises:

determining an air charge adjustment coefficient corresponding to the current oxygen closed-loop control learning factor and the current engine speed according to a third preset mapping relation to obtain a second air charge adjustment coefficient;

wherein, the third preset mapping relation records an oxygen closed-loop control learning factor and a corresponding relation between the engine speed and an air charge adjustment coefficient, and the air charge adjustment coefficient is reduced along with the reduction of the oxygen closed-loop control learning factor;

reducing a required air charge of the gas engine based on the second air charge adjustment factor;

determining an EGR rate adjustment coefficient corresponding to the current oxygen closed-loop control learning factor according to a fourth preset mapping relation to obtain a second EGR rate adjustment coefficient;

wherein, the fourth preset mapping relation records the corresponding relation between the oxygen closed-loop control learning factor and the EGR rate adjustment coefficient, and the EGR rate adjustment coefficient is increased along with the reduction of the oxygen closed-loop control learning factor;

increasing a required EGR rate of the gas engine based on the second EGR rate adjustment factor.

Optionally, if the target parameter includes an engine speed, the preset control condition includes that the engine speed is greater than a preset speed threshold;

if the target parameter comprises natural gas rail pressure, the preset control condition comprises that the natural gas rail pressure is larger than a preset rail pressure threshold value;

if the target parameter comprises an oxygen closed-loop control function state, the preset control condition comprises that the oxygen closed-loop control function is in an enabling state;

if the target parameter comprises an oxygen closed-loop control correction factor self-learning function state, the preset control condition comprises that the oxygen closed-loop control correction factor self-learning function is in an enabling state;

and if the target parameter comprises the working state of the control valve related to the engine operation, the preset control condition comprises that the control valve related to the engine operation is in a normal state.

Optionally, the gas engine control method according to any one of the first aspect of the present invention further includes:

and correcting the gas injection quantity of the gas engine according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor.

In a second aspect, the present invention provides a gas engine control device comprising:

the first acquisition unit is used for acquiring target parameters representing the running state of the gas engine;

the second acquisition unit is used for acquiring a current oxygen closed-loop control correction factor, a current oxygen closed-loop control learning factor and a current engine speed if the target parameter meets a preset control condition;

the judging unit is used for judging whether the gas engine meets a preset correction condition or not according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor;

and the first correction unit is used for correcting the required air charge and the required EGR rate of the gas engine according to the current oxygen closed-loop control learning factor and the current engine rotating speed if the gas engine meets the preset correction condition.

Optionally, the determining unit is configured to determine whether the gas engine meets a preset correction condition according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor, and specifically includes:

if the current oxygen closed-loop control correction factor is greater than or equal to a first preset factor threshold and the current oxygen closed-loop control learning factor is greater than or equal to a second preset factor threshold,

or, the current oxygen closed-loop control correction factor is less than or equal to a third preset factor threshold value and the current oxygen closed-loop control learning factor is less than or equal to a fourth preset factor threshold value, and the gas engine is judged to meet a preset correction condition;

if the current oxygen closed-loop control correction factor is less than the first predetermined factor threshold,

or, the current oxygen closed-loop control learning factor is smaller than the second preset factor threshold,

or, the current oxygen closed-loop control correction factor is larger than the third preset factor threshold,

or, the current oxygen closed-loop control learning factor is larger than the fourth preset factor threshold value, and the gas engine is judged not to meet the preset correction condition;

the first preset factor threshold is greater than the third preset factor threshold, and the second preset factor threshold is greater than the fourth preset factor threshold.

Optionally, the gas engine control apparatus according to a second aspect of the present invention further includes:

and the second correction unit is used for correcting the gas injection quantity of the gas engine according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor.

Based on the technical scheme, after the target parameter representing the running state of the gas engine is obtained, if the target parameter meets the preset control condition, the current oxygen closed-loop control correction factor, the current oxygen closed-loop control learning factor and the current engine speed are obtained, whether the gas engine meets the preset correction condition or not is judged according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor, and if the gas engine meets the preset correction condition, the required air charge and the required EGR rate of the gas engine are corrected according to the current oxygen closed-loop control learning factor and the current engine speed. Compared with the mode that the fuel information is sent to the engine controller in a message mode through the vehicle control unit in the prior art, and then the engine controller judges whether to replace the natural gas according to the fuel information, the scheme judges whether the gas engine meets the preset correction condition according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor, namely judges whether the natural gas is replaced, and does not depend on the message to transmit the fuel information any more, so that the method can be suitable for vehicles which cannot send messages between the vehicle control unit and the engine controller, and solves the problems of over-power, knocking, insufficient power, fire and the like of the engine.

Furthermore, the detection requirement that the gas engine forbids receiving information of other controllers in the authentication process can be met, so that whether gas replacement occurs or not can be accurately judged in the authentication process of the gas engine, and the authentication process can be successfully completed.

Furthermore, on the basis of the prior art, the method corrects the required air charge and the required EGR rate of the gas engine according to the current oxygen closed-loop control learning factor and the current engine rotating speed under the condition of meeting the preset correction condition, and is matched with the corrected gas injection quantity, so that the probability of faults of over-power, knocking, insufficient power, fire and the like of the engine can be effectively reduced, and the running stability of the gas engine is further improved.

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 introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a flow chart of a gas engine control method provided by an embodiment of the present invention;

FIG. 2 is a flow chart of another gas engine control method provided by an embodiment of the present invention;

fig. 3 is a block diagram showing a configuration of a gas engine control device according to an embodiment of the present invention;

fig. 4 is a block diagram showing another gas engine control device according to the embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, 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 some, but not all, embodiments of the present invention. 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.

Referring to fig. 1, fig. 1 is a flowchart of a gas engine control method according to an embodiment of the present invention, where the method may be applied to an on-vehicle controller, specifically, an engine controller, or of course, another controller with data processing capability that is disposed on a vehicle, such as a vehicle controller. Referring to fig. 1, a flow of a gas engine control method provided in an embodiment of the present invention may include:

s100, acquiring target parameters representing the running state of the gas engine.

Optionally, the target parameter capable of characterizing the operation state of the gas engine adopted by the embodiment of the invention may include: engine speed, natural gas rail pressure, oxygen closed loop control function state, oxygen closed loop control correction factor self-learning function state, and operating states of control valves associated with engine operation, such as fuel injection valves, oxygen sensors, and EGR valves. Of course, other parameters capable of representing the operation state of the gas engine can be included according to the actual control requirement and the specific structure of the gas engine, and the parameters also belong to the protection scope of the invention on the premise of not exceeding the core idea scope of the invention.

And S110, judging whether the target parameters meet preset control conditions, if so, executing S120.

As can be seen from the content of S100, the specific selection of the target parameter is different, and the corresponding preset control condition is also adjusted accordingly.

Specifically, if the target parameter includes the engine speed, the preset control condition includes that the engine speed is greater than a preset speed threshold;

if the target parameter comprises natural gas rail pressure, the preset control condition comprises that the natural gas rail pressure is larger than a preset rail pressure threshold value;

if the target parameter comprises an oxygen closed-loop control function state, the preset control condition comprises that the oxygen closed-loop control function is in an enabling state;

if the target parameter comprises an oxygen closed-loop control correction factor self-learning function state, the preset control condition comprises that the oxygen closed-loop control correction factor self-learning function is in an enabling state;

if the target parameter includes an operating state of a control valve associated with engine operation, the preset control condition includes that the control valve associated with engine operation is in a normal state. For example, there is no fuel injection valve electrical failure, no fuel injection valve internal leakage failure, the oxygen sensor is normal, the EGR is operating normally, and so on.

If the preset control condition is met through judgment, only the subsequent steps are needed to judge whether the required air charge and the required EGR rate of the gas engine are needed to be corrected.

And S120, acquiring a current oxygen closed-loop control correction factor, a current oxygen closed-loop control learning factor and a current engine speed.

Specifically, the gas engine control is generally performed by performing PID closed-loop control on a preset air-fuel ratio and an actual air-fuel ratio acquired by an oxygen sensor, and the output of the PID controller, i.e., an oxygen closed-loop control correction factor, is used for correcting the gas injection amount, so as to achieve consistency between the actual air-fuel ratio and the required air-fuel ratio. In practical applications, the oxygen closed-loop control correction factor can be obtained based on the prior art, and the oxygen closed-loop control correction factor can be directly obtained by the embodiment of the invention.

In the prior art, most gas vehicles have an oxygen closed-loop control learning factor self-learning function, the function is mainly to perform self-adaptation of fuel mixture control deviation, and the oxygen closed-loop control learning factor is self-learned under a specific working condition, so that the deviation caused by fuel composition gas quality difference, fuel rail pressure difference, injection valve fault or aging can be self-learned, and the oxygen closed-loop control learning factor is output to the function. Accordingly, the current oxygen closed-loop control learning factor mentioned in the present embodiment is the oxygen closed-loop control learning factor in the current control period. In practical applications, the learning factor of the oxygen closed-loop control can also be obtained based on the prior art, and the invention is not limited thereto.

As for the current engine speed, it should be particularly noted that, if the target parameter in S100 includes the engine speed, the current engine speed in this step is different from the engine speed adopted when determining whether the gas engine meets the preset control condition, and the current engine speed and the engine speed are not obtained at the same time.

S130, judging whether the gas engine meets a preset correction condition, if so, executing S140.

And judging whether the gas engine meets the preset correction condition or not according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor.

Specifically, if the current oxygen closed-loop control correction factor is greater than or equal to a first preset factor threshold value and the current oxygen closed-loop control learning factor is greater than or equal to a second preset factor threshold value, or the current oxygen closed-loop control correction factor is less than or equal to a third preset factor threshold value and the current oxygen closed-loop control learning factor is less than or equal to a fourth preset factor threshold value, it is determined that the gas engine meets the preset correction condition.

The first preset factor threshold is larger than a third preset factor threshold, and the second preset factor threshold is larger than a fourth preset factor threshold. Further, based on the comparison process, it can be seen that the first preset factor threshold and the third preset factor threshold form a first factor range corresponding to the current oxygen closed-loop control correction factor, the second preset factor threshold and the fourth preset factor threshold form a second factor range corresponding to the current oxygen closed-loop control learning factor, and if both the oxygen closed-loop control correction factor and the oxygen closed-loop control learning factor are greater than or equal to the upper limit values of the respective factor ranges or are less than or equal to the lower limit values of the respective factor ranges, it may be determined that the preset correction condition is met, which indicates that new natural gas is added to the entire vehicle.

Conversely, if at least one of the oxygen closed-loop-control correction factor and the oxygen closed-loop-control learning factor is within the corresponding factor range, it may be determined that the preset correction condition is not satisfied. Specifically, if the current oxygen closed-loop control correction factor is smaller than a first preset factor threshold, or the current oxygen closed-loop control learning factor is smaller than a second preset factor threshold, or the current oxygen closed-loop control correction factor is larger than a third preset factor threshold, or the current oxygen closed-loop control learning factor is larger than a fourth preset factor threshold, it is determined that the gas engine does not meet the preset correction condition. Under the condition, the required air charge and the required EGR rate of the gas engine do not need to be corrected, and the current control period is directly exited.

It should be noted that, for the specific values of the four preset factor thresholds, specific control requirements and performance parameter selection of the gas engine need to be combined, and the specific values of the four preset factor thresholds are not limited in the present invention.

And S140, correcting the required air charge and the required EGR rate of the gas engine according to the current oxygen closed-loop control learning factor and the current engine speed.

Under the condition that the gas engine meets the preset correction condition, the required air charge and the required EGR rate of the gas engine can be corrected according to the current oxygen closed-loop control learning factor and the current engine rotating speed, and as for a specific correction mode, the specific correction mode is developed in the subsequent content.

In summary, compared with the mode that the vehicle control unit sends the fuel information to the engine controller in the form of the message in the prior art, and then the engine controller judges whether to replace the natural gas according to the fuel information, the scheme judges whether the gas engine meets the preset correction condition according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor, namely judges whether to replace the natural gas, and does not rely on the message to transmit the fuel information any more, so that the method can be applied to vehicles which cannot send messages between the vehicle control unit and the engine controller, and solves the problems of over-power, knocking, insufficient power, fire and the like of the engine.

Furthermore, the detection requirement that the gas engine forbids receiving information of other controllers in the authentication process can be met, so that whether gas replacement occurs or not can be accurately judged in the authentication process of the gas engine, and the authentication process can be successfully completed.

Furthermore, on the basis of the prior art, the method corrects the required air charge and the required EGR rate of the gas engine according to the current oxygen closed-loop control learning factor and the current engine rotating speed under the condition of meeting the preset correction condition, and is matched with the corrected gas injection quantity, so that the probability of faults of over-power, knocking, insufficient power, fire and the like of the engine can be effectively reduced, and the running stability of the gas engine is further improved.

Optionally, referring to fig. 2, fig. 2 is a flowchart of another gas engine control method provided in an embodiment of the present invention, where the flowchart of the control method provided in this embodiment may include:

and S200, acquiring target parameters representing the running state of the gas engine.

Optionally, an alternative implementation of S200 may be implemented with reference to S100 in the embodiment shown in fig. 1, and will not be repeated here.

S210, judging whether the target parameters meet preset control conditions, if so, executing S220.

Optionally, an alternative implementation of S210 may be implemented with reference to S210 in the embodiment shown in fig. 1, and will not be repeated here.

And S220, acquiring a current oxygen closed-loop control correction factor, a current oxygen closed-loop control learning factor and a current engine speed.

Optionally, an alternative implementation of S220 may be implemented with reference to S220 in the embodiment shown in fig. 1, and will not be repeated here.

S230, judging whether the current oxygen closed-loop control correction factor is larger than or equal to a first preset factor threshold value and the current oxygen closed-loop control learning factor is larger than or equal to a second preset factor threshold value, if so, executing S240, and if not, executing S250.

The selection and magnitude relationship between the first predetermined factor threshold and the second predetermined factor threshold can be referred to the foregoing, and will not be repeated here. If the judgment condition of the step is not satisfied, S250 is executed to further judge the current oxygen closed-loop control correction factor and the current oxygen closed-loop learning factor.

And S240, increasing the required air charge of the gas engine according to the current oxygen closed-loop control learning factor, and reducing the required EGR rate of the gas engine.

And under the condition that the current oxygen closed-loop control correction factor is greater than or equal to a first preset factor threshold value and the current oxygen closed-loop control learning factor is greater than or equal to a second preset factor threshold value, increasing the required air charge of the gas engine according to the current oxygen closed-loop control learning factor, and reducing the required EGR rate of the gas engine.

Optionally, the current oxygen closed-loop control correction factor is greater than or equal to a first preset factor threshold value, and the current oxygen closed-loop control learning factor is greater than or equal to a second preset factor threshold value, which indicates that the natural gas currently used by the whole vehicle belongs to the low-calorific-value natural gas, the duration time that the low-calorific-value natural gas adaptive control function can be in the enabling state is counted, if the duration time that the low-calorific-value natural gas adaptive control function can be in the enabling state reaches the first time threshold value, the determination of S230 can be determined to be credible, and then the step can be executed. The first time threshold value can be determined based on actual operation experience and performance parameters of the gas engine, and specific values of the first time threshold value are not limited.

Optionally, the embodiment provides a first preset mapping relationship and a second preset mapping relationship, wherein the first preset mapping relationship records an oxygen closed-loop control learning factor and a corresponding relationship between an engine speed and an air charge adjustment coefficient, the air charge adjustment coefficient increases with the increase of the oxygen closed-loop control learning factor, the second preset mapping relationship records a corresponding relationship between the oxygen closed-loop control learning factor and an EGR rate adjustment coefficient, and the EGR rate adjustment coefficient decreases with the increase of the oxygen closed-loop control learning factor.

Further, an air charge adjustment coefficient corresponding to the current oxygen closed-loop control learning factor and the current engine speed can be determined according to the first preset mapping relation, and a first air charge adjustment coefficient is obtained; and determining an EGR rate adjustment coefficient corresponding to the current oxygen closed-loop control learning factor according to the second preset mapping relation to obtain a first EGR rate adjustment coefficient. The method includes increasing a desired air charge of the gas engine based on a first air charge adjustment factor, and specifically, taking a product of the first air charge adjustment factor and a current desired air charge of the gas engine as the increased desired air charge, while decreasing a desired EGR rate of the gas engine based on a first EGR rate adjustment factor, and similarly, taking a product of the first EGR rate adjustment factor and the current desired EGR rate of the gas engine as the decreased desired EGR rate.

S250, judging whether the current oxygen closed-loop control correction factor is smaller than or equal to a third preset factor threshold value and the current oxygen closed-loop control learning factor is smaller than or equal to a fourth preset factor threshold value, if so, executing S260.

The selection and magnitude relationship between the third predetermined factor threshold and the fourth predetermined factor threshold can be implemented with reference to the embodiment shown in fig. 1, and will not be repeated here.

And S260, reducing the required air charge of the gas engine according to the current oxygen closed-loop control learning factor and the current engine speed, and increasing the required EGR rate of the gas engine.

And under the condition that the current oxygen closed-loop control correction factor is smaller than or equal to a third preset factor threshold value and the current oxygen closed-loop control learning factor is smaller than or equal to a fourth preset factor threshold value, reducing the required air charge of the gas engine according to the current oxygen closed-loop control learning factor and the current engine speed, and increasing the required EGR rate of the gas engine.

Optionally, similar to S240, if the current oxygen closed-loop control correction factor is less than or equal to the third preset factor threshold and the current oxygen closed-loop control learning factor is less than or equal to the fourth preset factor threshold, it is indicated that the high calorific value natural gas is currently used by the entire vehicle, the duration of the enabling state of the high calorific value natural gas adaptive control function is counted, and if the duration of the enabling state of the high calorific value natural gas adaptive control function reaches the second time threshold, it may be determined that the determination of S250 is authentic, and then the step may be executed. The second time threshold is selected according to the same rule as the first time threshold, and the first time threshold may even be selected according to the same value as the second time threshold, which is also optional.

Optionally, the present embodiment further provides a third preset mapping relationship and a fourth preset mapping relationship, wherein the third preset mapping relationship records the oxygen closed-loop control learning factor and the corresponding relationship between the engine speed and the air charge adjustment coefficient, the air charge adjustment coefficient decreases as the oxygen closed-loop control learning factor decreases, and the fourth preset mapping relationship records the corresponding relationship between the oxygen closed-loop control learning factor and the EGR rate adjustment coefficient, and the EGR rate adjustment coefficient increases as the oxygen closed-loop control learning factor decreases.

Further, an air charge adjustment coefficient corresponding to the current oxygen closed-loop control learning factor and the current engine speed is determined according to a third preset mapping relation, a second air charge adjustment coefficient is obtained, and the required air charge of the gas engine is reduced based on the second air charge adjustment coefficient, namely the product of the second air charge adjustment coefficient and the current required air charge of the gas engine is used as the reduced required air charge.

And determining an EGR rate adjustment coefficient corresponding to the current oxygen closed-loop control learning factor according to a fourth preset mapping relation to obtain a second EGR rate adjustment coefficient, and increasing the required EGR rate of the gas engine based on the second EGR rate adjustment coefficient, namely taking the product of the second EGR rate adjustment coefficient and the current required EGR rate of the gas engine as the increased required EGR rate.

Optionally, on the basis of any of the above embodiments, the gas engine control method provided by the present invention further includes: the gas injection quantity of the gas engine is corrected according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor, it should be noted that the specific process of correcting the gas injection quantity of the gas engine can be realized based on the prior art, and the invention is not limited to this.

In the following, a gas engine control apparatus provided in an embodiment of the present invention is described, where the gas engine control apparatus described below may be regarded as a functional module architecture that needs to be set in a central device to implement the gas engine control method provided in the embodiment of the present invention; the following description may be cross-referenced with the above.

Fig. 3 is a block diagram of a gas engine control apparatus according to an embodiment of the present invention, and referring to fig. 3, the apparatus may include:

a first obtaining unit 10, configured to obtain a target parameter representing an operating state of a gas engine;

a second obtaining unit 20, configured to obtain a current oxygen closed-loop control correction factor, a current oxygen closed-loop control learning factor, and a current engine speed if the target parameter meets a preset control condition;

the judging unit 30 is used for judging whether the gas engine meets the preset correction condition or not according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor;

and the first correcting unit 40 is used for correcting the required air charge and the required EGR rate of the gas engine according to the current oxygen closed-loop control learning factor and the current engine rotating speed if the gas engine meets the preset correcting condition.

Optionally, the determining unit 30 is configured to determine whether the gas engine meets a preset correction condition according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor, and includes:

if the current oxygen closed-loop control correction factor is greater than or equal to a first preset factor threshold and the current oxygen closed-loop control learning factor is greater than or equal to a second preset factor threshold,

or judging that the gas engine meets the preset correction condition when the current oxygen closed-loop control correction factor is less than or equal to a third preset factor threshold and the current oxygen closed-loop control learning factor is less than or equal to a fourth preset factor threshold;

if the current oxygen closed-loop control correction factor is less than the first predetermined factor threshold,

or the current oxygen closed-loop control learning factor is smaller than a second preset factor threshold value,

or, the current oxygen closed-loop control correction factor is larger than a third preset factor threshold value,

or judging that the gas engine does not meet the preset correction condition when the current oxygen closed-loop control learning factor is larger than a fourth preset factor threshold;

the first preset factor threshold is larger than a third preset factor threshold, and the second preset factor threshold is larger than a fourth preset factor threshold.

Optionally, the first correcting unit 40 is configured to correct the required air charge and the required EGR rate of the gas engine according to the current oxygen closed-loop control learning factor, and includes:

under the condition that the current oxygen closed-loop control correction factor is greater than or equal to a first preset factor threshold value and the current oxygen closed-loop control learning factor is greater than or equal to a second preset factor threshold value, the required air charge of the gas engine is increased according to the current oxygen closed-loop control learning factor, and the required EGR rate of the gas engine is reduced;

and under the condition that the current oxygen closed-loop control correction factor is less than or equal to a third preset factor threshold value and the current oxygen closed-loop control learning factor is less than or equal to a fourth preset factor threshold value, reducing the required air charge of the gas engine according to the current oxygen closed-loop control learning factor and increasing the required EGR rate of the gas engine.

Optionally, the first correcting unit 40, configured to increase the required air charge of the gas engine according to the current oxygen closed-loop control learning factor and the current engine speed, and decrease the required EGR rate of the gas engine, includes:

determining an air charge adjustment coefficient corresponding to the current oxygen closed-loop control learning factor and the current engine speed according to the first preset mapping relation to obtain a first air charge adjustment coefficient;

the first preset mapping relation records an oxygen closed-loop control learning factor and a corresponding relation between the engine speed and an air charge adjustment coefficient, and the air charge adjustment coefficient is increased along with the increase of the oxygen closed-loop control learning factor;

increasing a demanded air charge of the gas engine based on a first air charge adjustment coefficient;

determining an EGR rate adjustment coefficient corresponding to the current oxygen closed-loop control learning factor according to a second preset mapping relation to obtain a first EGR rate adjustment coefficient;

wherein, the second preset mapping relation records the corresponding relation between the oxygen closed-loop control learning factor and the EGR rate adjustment coefficient, and the EGR rate adjustment coefficient is reduced along with the increase of the oxygen closed-loop control learning factor;

the required EGR rate of the gas engine is reduced based on the first EGR rate adjustment coefficient.

Optionally, the first correcting unit 40, configured to decrease the required air charge of the gas engine according to the current oxygen closed-loop control learning factor and the current engine speed, and increase the required EGR rate of the gas engine, includes:

determining an air charge adjustment coefficient corresponding to the current oxygen closed-loop control learning factor and the current engine speed according to a third preset mapping relation to obtain a second air charge adjustment coefficient;

wherein, the third preset mapping relation records the aerobic closed-loop control learning factor and the corresponding relation between the engine speed and the air charge adjusting coefficient, and the air charge adjusting coefficient is reduced along with the reduction of the aerobic closed-loop control learning factor;

reducing a required air charge of the gas engine based on the second air charge adjustment coefficient;

determining an EGR rate adjustment coefficient corresponding to the current oxygen closed-loop control learning factor according to a fourth preset mapping relation to obtain a second EGR rate adjustment coefficient;

the fourth preset mapping relation records the corresponding relation between the oxygen closed-loop control learning factor and the EGR rate adjustment coefficient, and the EGR rate adjustment coefficient is increased along with the reduction of the oxygen closed-loop control learning factor;

the required EGR rate of the gas engine is increased based on the second EGR rate adjustment coefficient.

Alternatively, referring to fig. 4, fig. 4 is a block diagram of another gas engine control device according to an embodiment of the present invention, and on the basis of the embodiment shown in fig. 3, the device further includes:

and the second correction unit 50 is used for correcting the gas injection quantity of the gas engine according to the current oxygen closed-loop control correction factor and the current oxygen closed-loop control learning factor.

Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in Random Access Memory (RAM), memory, Read Only Memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

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.