CN117449968A

CN117449968A - Control method and control device of EGR valve and electronic equipment

Info

Publication number: CN117449968A
Application number: CN202311472972.6A
Authority: CN
Inventors: 赵鹏; 代子阳; 李丽丽; 贾锡臣; 潘发存
Original assignee: Weichai Power Co Ltd
Current assignee: Weichai Power Co Ltd
Priority date: 2023-11-07
Filing date: 2023-11-07
Publication date: 2024-01-26

Abstract

The application provides a control method, a control device and electronic equipment of an EGR valve. The method comprises the following steps: acquiring the cooled temperature and the current opening of the EGR valve; calculating cooling efficiency of the EGR cooler, acquiring a correction factor under the condition that the cooling efficiency is smaller than or equal to a first preset threshold value, calculating the product of the cooling efficiency, the correction factor and the current opening of the EGR valve to obtain a target opening of the EGR valve, and controlling the opening of the EGR valve to be the target opening of the EGR valve, wherein the correction factor is used for correcting the opening of the EGR valve, and the cooling efficiency is the efficiency of the EGR cooler for cooling the exhaust gas of the engine; and controlling the EGR valve to be closed under the condition that the cooling efficiency is larger than a first preset threshold value and the temperature after cooling is larger than or equal to a second preset threshold value. Through this application, solved the high temperature waste gas among the prior art and caused the problem that EGR valve was fused.

Description

Control method and control device of EGR valve and electronic equipment

Technical Field

The present application relates to the field of control of EGR valves, and in particular, to a control method, a control device, a computer-readable storage medium, and an electronic apparatus for an EGR valve.

Background

An EGR system (Exhaust Gas recirculation system of an engine, namely an EGR system for short) mainly comprises an EGR cooler, a one-way valve, an electric control EGR valve and the like. When the diesel engine adopts an electric control high-pressure cooling EGR system, waste gas is directly led into an EGR cooler from the front of the vortex, and after being cooled by the EGR cooler, the waste gas flows into an air inlet pipeline through a one-way valve and an electric control EGR valve, and the one-way valve is arranged to avoid fresh air backflow when the air inlet pressure is higher than the front pressure of the vortex under certain working conditions. During the operation of the diesel engine, when the EGR cooler fails, the temperature of the exhaust gas introduced from the front of the vortex is too high, so that the conditions of burning of the EGR check valve and burning of the electric control EGR valve are caused, and the engine is caused to fail. The existing method can monitor the cooling efficiency of the EGR cooler and report related faults, and cause engine torque limitation, but the engine still operates, the high-temperature EGR exhaust gas flow still passes through the check valve and the EGR valve, the EGR check valve and the EGR valve can be impacted or burned by high-temperature gas, and the engine intake temperature is abnormal and the NOx emission is abnormal.

Therefore, a solution to the problem of EGR valve burn-out is needed.

Disclosure of Invention

The main object of the present application is to provide a control method, a control device, a computer readable storage medium and an electronic device for an EGR valve, so as to at least solve the problem of EGR burning caused by high temperature exhaust gas in the prior art.

In order to achieve the above object, according to one aspect of the present application, there is provided a control method of an EGR valve, the EGR valve being included in an EGR system, the EGR system further including an EGR cooler and a check valve, the EGR cooler, the check valve, and the EGR valve being sequentially connected in order, including: acquiring the gas temperature of the exhaust gas of the engine after being cooled by the EGR cooler, obtaining the cooled temperature, and acquiring the current opening of the EGR valve to obtain the current opening of the EGR valve, wherein the EGR system is contained in the engine; calculating cooling efficiency of the EGR cooler, obtaining a correction factor when the cooling efficiency is smaller than or equal to a first preset threshold value, calculating a product of the cooling efficiency, the correction factor and the current opening of the EGR valve to obtain an EGR valve target opening, and controlling the opening of the EGR valve to be the EGR valve target opening when the EGR valve target opening is different from the current opening of the EGR valve, wherein the correction factor is used for correcting the opening of the EGR valve, and the cooling efficiency is the efficiency of the EGR cooler for cooling exhaust gas of the engine; and controlling the EGR valve to be closed under the condition that the cooling efficiency is greater than the first preset threshold value and the cooled temperature is greater than or equal to the second preset threshold value.

Optionally, calculating the cooling efficiency of the EGR cooler includes: acquiring the temperature of the gas of the exhaust gas of the engine which is not cooled by the EGR cooler, and obtaining the temperature before cooling; and calculating the ratio of the temperature after cooling to the temperature before cooling, and calculating the difference between 1 and the ratio to obtain the cooling efficiency.

Optionally, obtaining the correction factor includes: acquiring a plurality of historical cooled temperatures, a plurality of historical EGR valve flows, each historical cooled temperature and a historical correction factor corresponding to each historical EGR valve flow, and obtaining a one-to-one mapping relation of the cooled temperatures, the EGR valve flows and the correction factors; and acquiring the current EGR valve flow, determining the historical correction factors corresponding to the cooled temperature and the current EGR valve flow according to the one-to-one mapping relation of the cooled temperature, the EGR valve flow and the correction factors, and obtaining the correction factors.

Optionally, in a case where the cooling efficiency is less than or equal to a first preset threshold value or in a case where the cooling efficiency is greater than the first preset threshold value and the post-cooling temperature is greater than or equal to the second preset threshold value, the control method further includes: controlling the EGR cooler to generate an alarm signal to prompt the failure of the EGR cooler when the duration of the cooling efficiency less than or equal to the first preset threshold is greater than or equal to a first preset time period; and controlling the EGR cooler to generate the alarm signal to prompt the failure of the EGR cooler under the condition that the duration time of the cooling efficiency being greater than the first preset threshold value is greater than or equal to a second preset time period and the duration time of the cooled temperature being greater than or equal to the second preset threshold value is greater than or equal to the second preset time period.

Optionally, the control method further includes: acquiring the current torque of the engine, wherein the EGR system is contained in the engine; calculating the product of the cooling efficiency, the correction factor and the current torque to obtain a target torque under the condition that the cooling efficiency is smaller than or equal to the first preset threshold value, and controlling the engine to run at the target torque; and controlling the rotating speed of the engine to be idle under the condition that the temperature after cooling is greater than or equal to the second preset threshold value.

Optionally, the control method further includes: acquiring the current rotating speed and the current oil quantity of the engine; determining a cooling efficiency threshold corresponding to the current rotating speed and the current oil quantity through a one-to-one mapping relation of the rotating speed, the oil quantity and the cooling efficiency threshold to obtain the first preset threshold, wherein the one-to-one mapping relation of the rotating speed, the oil quantity and the cooling efficiency threshold comprises a plurality of historical rotating speeds and the historical oil quantity and the historical cooling efficiency threshold corresponding to each historical rotating speed; and determining the temperature threshold corresponding to the current rotating speed and the current oil quantity through a one-to-one mapping relation of the rotating speed, the oil quantity and the cooled temperature threshold, and obtaining the second preset threshold, wherein the one-to-one mapping relation of the rotating speed, the oil quantity and the cooled temperature threshold comprises a plurality of historical rotating speeds and the historical oil quantity and the historical temperature threshold corresponding to each historical rotating speed.

Optionally, obtaining a gas temperature of exhaust gas of the engine after cooling by the EGR cooler, to obtain a cooled temperature, including: and under the conditions that the current opening of the EGR valve is larger than or equal to 0 and the engine where the EGR system is positioned has no error, acquiring the gas temperature of the exhaust gas of the engine after the exhaust gas is cooled by the EGR cooler, and obtaining the cooled temperature.

According to another aspect of the present application, there is provided a control apparatus of an EGR valve included in an EGR system, the EGR system further including an EGR cooler and a check valve, the EGR cooler, the check valve and the EGR valve being sequentially connected in order, including: a first obtaining unit, configured to obtain a gas temperature of exhaust gas of an engine after the exhaust gas passes through the EGR cooler to obtain a cooled temperature, and obtain a current opening of the EGR valve to obtain a current opening of the EGR valve, where the EGR system is included in the engine; a first control unit, configured to calculate a cooling efficiency of the EGR cooler, obtain a correction factor when the cooling efficiency is less than or equal to a first preset threshold, calculate a product of the cooling efficiency, the correction factor, and a current opening of the EGR valve, obtain an EGR valve target opening, and control the opening of the EGR valve to be the EGR valve target opening when the EGR valve target opening is different from the EGR valve current opening, where the correction factor is used to correct the opening of the EGR valve, and the cooling efficiency is an efficiency of the EGR cooler to cool exhaust gas of the engine; and a second control unit configured to control the EGR valve to be closed in a case where the cooling efficiency is greater than the first preset threshold and the post-cooling temperature is greater than or equal to the second preset threshold.

According to still another aspect of the present application, there is provided a computer-readable storage medium including a stored program, wherein the program, when executed, controls a device in which the computer-readable storage medium is located to perform any one of the control methods.

According to still another aspect of the present application, there is provided an electronic apparatus including: one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs comprising instructions for performing any one of the control methods.

By applying the technical scheme, the cooled temperature of the EGR cooler and the current opening of the EGR valve in the EGR system are obtained, the cooling efficiency of the EGR cooler is calculated, and under the condition that the cooling efficiency is smaller than a first preset threshold value, the product of the cooling efficiency, the correction factor and the current opening of the EGR valve is calculated to obtain the target opening of the EGR valve; and controlling the EGR valve to be closed under the condition that the cooling efficiency is larger than a first preset threshold value and the cooled temperature is larger than a second preset threshold value. Therefore, through monitoring the cooling efficiency and the temperature after cooling of the EGR cooler, when the cooling efficiency of the EGR is low or the temperature after cooling is too high, the circulation of exhaust gas of the EGR valve can be timely reduced or interrupted, and the EGR valve is prevented from being burnt due to hot gas impact. Compared with the prior art, after the fault of the EGR cooler, the high-temperature EGR waste flow still flows through the EGR valve, and the EGR valve is burnt and melted, the high-temperature waste flow of the EGR valve is timely reduced or interrupted, the problems of further burnt and melted of the EGR valve or damage and the like are avoided, and therefore the problem that the burnt and melted of the EGR valve is caused by high-temperature waste gas in the prior art can be solved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application and do not constitute an undue limitation to the application. In the drawings:

fig. 1 is a block diagram showing a hardware configuration of a mobile terminal that performs a control method of an EGR valve according to an embodiment of the present application;

fig. 2 shows a flow chart of a control method of an EGR valve according to an embodiment of the present application;

FIG. 3 shows a flow chart of a method for calculating cooling efficiency in a control method of an EGR valve according to an embodiment of the present application;

FIG. 4 shows a schematic diagram of an engine device to which a control method of an EGR valve is applied according to an embodiment of the present application;

FIG. 5 illustrates a flow diagram of a particular method of controlling an EGR valve provided by embodiments of the present application;

fig. 6 shows a block diagram of a control device of an EGR valve provided in an embodiment of the present application.

Wherein the above figures include the following reference numerals:

102. a processor; 104. a memory; 106. a transmission device; 108. an input-output device; 1. an EGR cooler front temperature sensor; 2. an EGR cooler post temperature sensor; 3. an EGR cooler; 4. a one-way valve; 5. an EGR valve; 6. an intake manifold; 7. an exhaust manifold.

Detailed Description

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

In order to make the present application solution better understood by those skilled in the art, the following description will be made in detail and with reference to the accompanying drawings in the embodiments of the present application, it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, shall fall within the scope of the present application.

It should be noted that the terms "first," "second," and the like in the description and claims of the present application and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate in order to describe the embodiments of the present application described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

For convenience of description, the following will describe some terms or terms related to the embodiments of the present application:

EGR system: an Exhaust Gas recirculation system, an EGR system for short, returns a part of the Exhaust Gas discharged from the engine to the intake manifold and Re-enters the cylinder together with the fresh mixture.

As described in the background art, in the prior art, high-temperature exhaust gas may cause EGR burning under the condition of failure of an EGR cooler, and in order to solve the problem that high-temperature exhaust gas may cause EGR burning, embodiments of the present application provide a control method, a control device, a computer-readable storage medium, and an electronic device for an EGR valve.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

The method embodiments provided in the embodiments of the present application may be performed in a mobile terminal, a computer terminal or similar computing device. Taking the operation on a mobile terminal as an example, fig. 1 is a block diagram of a hardware structure of a mobile terminal according to a control method of an EGR valve according to an embodiment of the present invention. As shown in fig. 1, a mobile terminal may include one or more (only one is shown in fig. 1) processors 102 (the processor 102 may include, but is not limited to, a microprocessor MCU or a processing device such as a programmable logic device FPGA) and a memory 104 for storing data, wherein the mobile terminal may also include a transmission device 106 for communication functions and an input-output device 108. It will be appreciated by those skilled in the art that the structure shown in fig. 1 is merely illustrative and not limiting of the structure of the mobile terminal described above. For example, the mobile terminal may also include more or fewer components than shown in fig. 1, or have a different configuration than shown in fig. 1.

The memory 104 may be used to store a computer program, for example, a software program of application software and a module, such as a computer program corresponding to a control method of the EGR valve in the embodiment of the present invention, and the processor 102 executes the computer program stored in the memory 104 to perform various functional applications and data processing, that is, implement the above-mentioned method. Memory 104 may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include memory remotely located relative to the processor 102, which may be connected to the mobile terminal via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof. The transmission device 106 is used to receive or transmit data via a network. Specific examples of the network described above may include a wireless network provided by a communication provider of the mobile terminal. In one example, the transmission device 106 includes a network adapter (Network Interface Controller, simply referred to as NIC) that can connect to other network devices through a base station to communicate with the internet. In one example, the transmission device 106 may be a Radio Frequency (RF) module, which is configured to communicate with the internet wirelessly.

In the present embodiment, there is provided a control method of an EGR valve operating on a mobile terminal, a computer terminal, or the like, it should be noted that the steps shown in the flowchart of the drawings may be performed in a computer system such as a set of computer executable instructions, and that although a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in an order different from that herein.

Fig. 2 is a flowchart of a control method of an EGR valve according to an embodiment of the present application, the EGR valve being included in an EGR system, the EGR system further including an EGR cooler and a check valve, the EGR cooler, the check valve, and the EGR valve being sequentially connected in order, as shown in fig. 2, the method including the steps of:

step S201, obtaining the gas temperature of the exhaust gas of the engine after being cooled by the EGR cooler, obtaining the cooled temperature, and obtaining the current opening of the EGR valve, wherein the EGR system is contained in the engine;

specifically, EGR is an exhaust gas recirculation system of an engine, exhaust gas of the engine is reintroduced through an intake manifold and reintroduced into a cylinder together with fresh air mixture, the process firstly needs to be cooled by an EGR cooler, otherwise, high-temperature gas can cause a problem of melting through a one-way valve, therefore, a temperature sensor before the EGR cooler and a temperature sensor after the EGR cooler are usually arranged on the EGR cooler, and the temperature of the exhaust gas of the engine before and after the exhaust gas is cooled by the EGR cooler can be measured through corresponding sensors, and the current opening degree of the EGR valve needs to be obtained so as to facilitate the subsequent judgment of whether the EGR cooler has a fault.

Step S202, calculating cooling efficiency of the EGR cooler, obtaining a correction factor when the cooling efficiency is smaller than or equal to a first preset threshold value, calculating a product of the cooling efficiency, the correction factor and the current opening of the EGR valve to obtain an EGR valve target opening, and controlling the opening of the EGR valve to be the EGR valve target opening when the EGR valve target opening is different from the current opening of the EGR valve, wherein the correction factor is used for correcting the opening of the EGR valve, and the cooling efficiency is the efficiency of the EGR cooler for cooling exhaust gas of the engine;

specifically, whether the EGR cooler can cool the exhaust gas of the engine, namely, whether the engine can work normally is generally determined through the cooling efficiency of the EGR cooler, therefore, the cooling efficiency of the EGR cooler is calculated first, the first preset threshold, namely, the EGR cooler efficiency threshold corresponding to the current rotation speed and the oil quantity, is obtained through the MAP query calibrated in advance, that is, the efficiency threshold which the EGR cooler should reach under the condition that the calculated EGR cooling efficiency is smaller than or equal to the efficiency threshold, the condition that the efficiency of the EGR cooler does not reach the minimum requirement is further indicated, and the condition that the cooling efficiency of the EGR cooler is low and the EGR cooler fails is further indicated. In this case, a correction factor is obtained by querying the pre-calibrated EGR cooled temperature, the EGR exhaust gas flow and the correction factor MAP according to the cooled temperature and the current exhaust gas flow, and after the correction factor is obtained, the current opening of the EGR valve is corrected by calculating the product of the cooling efficiency, the correction factor and the current opening of the EGR valve to obtain the target opening of the EGR valve, wherein the value of the correction factor is smaller than 1, i.e., the target opening of the EGR valve is reduced compared with the current opening of the EGR valve.

And step S203, controlling the EGR valve to close when the cooling efficiency is greater than the first preset threshold and the post-cooling temperature is greater than or equal to the second preset threshold.

Specifically, under the condition that the cooling efficiency is normal, that is, the cooling efficiency is greater than a first preset threshold, whether the cooled temperature is greater than or equal to a second preset threshold is judged, the second preset threshold is a maximum temperature threshold corresponding to the rotating speed and the oil quantity, and the maximum temperature threshold is generally the limit high temperature born by the EGR check valve minus 20 ℃. When the temperature after cooling of the cooler is greater than or equal to the maximum temperature threshold, the temperature after cooling is too high, and the cooler cannot cool waste, and the cooler fails, and in this case, the opening of the EGR valve is directly controlled to be 0, namely the EGR valve is closed. The smaller the cooling efficiency of the EGR cooler, the faster the EGR valve closing rate.

According to the method, the temperature after cooling of the EGR cooler and the current opening of the EGR valve in the EGR system are obtained, the cooling efficiency of the EGR cooler is calculated, and under the condition that the cooling efficiency is smaller than a first preset threshold value, the product of the cooling efficiency, the correction factor and the current opening of the EGR valve is calculated, so that the target opening of the EGR valve is obtained; and controlling the EGR valve to be closed under the condition that the cooling efficiency is larger than a first preset threshold value and the cooled temperature is larger than a second preset threshold value. Therefore, through monitoring the cooling efficiency and the temperature after cooling of the EGR cooler, when the cooling efficiency of the EGR is low or the temperature after cooling is too high, the circulation of exhaust gas of the EGR valve can be timely reduced or interrupted, and the EGR valve is prevented from being burnt due to hot gas impact. Compared with the prior art, after the fault of the EGR cooler, the high-temperature EGR waste flow still flows through the EGR valve, and the EGR valve is burnt and melted, the high-temperature waste flow of the EGR valve is timely reduced or interrupted, the problems of further burnt and melted of the EGR valve or damage and the like are avoided, and therefore the problem that the burnt and melted of the EGR valve is caused by high-temperature waste gas in the prior art can be solved.

In a specific implementation process, the step S202 may be implemented by the following steps: as shown in fig. 3: step S2021: acquiring the temperature of the exhaust gas of the engine which is not cooled by the EGR cooler, and obtaining the temperature before cooling; step S2022: and calculating the ratio of the temperature after cooling to the temperature before cooling, and calculating the difference between 1 and the ratio to obtain the cooling efficiency. According to the method, the cooling efficiency is obtained through calculation of the temperature before cooling and the temperature after cooling, so that the cooling efficiency can be accurately obtained through calculation, and whether the EGR cooler is in failure or not is determined through the cooling efficiency.

Specifically, the cooling efficiency can be calculated by (1-post-cooling temperature/pre-cooling temperature), so that the cooling efficiency can be accurately obtained by only re-acquiring the pre-cooling temperature and calculating the pre-cooling temperature, the pre-cooling temperature and the post-cooling temperature can be measured by temperature sensors arranged at the front end and the rear end of the EGR cooler, the front end and the rear end refer to the front end at the end through which the air flows first and the rear end at the rear end according to the direction of the air flow.

In order to accurately acquire the correction factor to correct the opening degree of the EGR valve, the above step S202 of the present application may also be implemented by: acquiring a plurality of historical cooling temperatures, a plurality of historical EGR valve flows, each historical cooling temperature and a historical correction factor corresponding to each historical EGR valve flow, and obtaining a one-to-one mapping relation of the cooled temperatures, the EGR valve flows and the correction factors; and acquiring the current EGR valve flow, and determining a historical correction factor corresponding to the cooled temperature and the current EGR valve flow according to the one-to-one mapping relation of the cooled temperature, the EGR valve flow and the correction factor to obtain the correction factor. According to the method, the historical correction factors are calibrated according to the temperature after historical cooling and the flow of the historical EGR valve, and the one-to-one mapping relation between the parameters is obtained, so that the correction factors corresponding to the current temperature after cooling and the current flow of the EGR valve can be determined through the one-to-one mapping relation.

In the specific implementation process, a plurality of historical cooling temperatures, a plurality of historical EGR valve flows and historical correction factors corresponding to the parameters are obtained through a test or simulation mode and the like, so that a one-to-one mapping relation of the cooling temperatures, the EGR valve flows and the correction factors is obtained, wherein the one-to-one mapping relation can be expressed in a MAP, namely a MAP, or in a form of a table with the one-to-one mapping relation. After the cooled temperature and the current EGR valve flow rate are obtained, a historical correction factor corresponding to the cooled temperature and the current EGR valve flow rate, which are identical to the cooled temperature and the current EGR valve flow rate in the one-to-one mapping relationship, can be determined as a correction factor corresponding to the cooled temperature and the current EGR valve flow rate.

The above method further comprises the steps of, for example: controlling the EGR cooler to generate an alarm signal to prompt the failure of the EGR cooler when the duration of the cooling efficiency being less than or equal to the first preset threshold is greater than or equal to a first preset time period; and controlling the EGR cooler to generate the alarm signal to prompt the failure of the EGR cooler when the duration of the cooling efficiency being greater than the first preset threshold value is greater than or equal to a second preset time period and the duration of the cooled temperature being greater than or equal to the second preset threshold value is greater than or equal to the second preset time period. According to the method, under the condition that the cooling efficiency or the cooled temperature shows that the cooler is faulty, an alarm signal is generated to prompt the fault of the EGR cooler, prompt a driver to troubleshoot the fault, and ensure the safety of an EGR system and the stability of an engine or emission of a subsequent vehicle.

Specifically, in the case where the duration of the cooling efficiency is equal to or less than the first preset threshold value is equal to or greater than a first preset time period, or in the case where the duration of the cooling efficiency is equal to or greater than the first preset threshold value is equal to or greater than a second preset time period and the duration of the post-cooling temperature is equal to or greater than the second preset threshold value is equal to or greater than the second preset time period, an EGR cooler failure is indicated, and therefore, an alarm signal, that is, an EGR cooler failure report, is generated, the engine lights up and the driver is prompted to perform a process in time.

In order to limit the torque of the engine in time in case of failure of the EGR cooler, avoiding causing the failure of the engine, the above method may further comprise, in some embodiments, the steps of: acquiring the current torque of the engine, wherein the EGR system is contained in the engine; calculating a product of the cooling efficiency, the correction factor, and the current torque to obtain a target torque, and controlling the engine to operate at the target torque when the cooling efficiency is less than or equal to the first preset threshold; and controlling the rotation speed of the engine to be idle under the condition that the temperature after cooling is greater than or equal to the second preset threshold value. The method also corrects the engine torque through the correction factors, so that the EGR opening degree can be limited and the EGR torque can be limited at the same time under the condition of the failure of the EGR cooler, thereby avoiding the failure of an EGR valve and the engine.

In the specific implementation process, the opening degree of the EGR valve is controlled to be reduced to be a target opening degree or closed, and simultaneously the torque of the engine is limited, and when the cooling efficiency is smaller than or equal to the first preset threshold value, namely, the cooling efficiency is lower than an efficiency threshold value, the product of the cooling efficiency, the correction factor and the current torque is calculated, the current torque is corrected to obtain the target torque, and the engine is controlled to operate at the target torque; and multiplying 0, a correction factor and the current torque to obtain a target torque, namely, the target torque is 0, and controlling the torque of the engine to be 0 or the rotating speed of the engine to be idling, namely, the engine is operated in a neutral gear when the cooled temperature is larger than or equal to the second preset threshold value, namely, the cooled temperature is higher than the maximum temperature threshold value.

In some alternative embodiments, the control method further includes the steps of: acquiring the current rotating speed and the current oil quantity of the engine; determining a cooling efficiency threshold corresponding to the current rotating speed and the current oil quantity through a one-to-one mapping relation of the rotating speed, the oil quantity and the cooling efficiency threshold to obtain the first preset threshold, wherein the one-to-one mapping relation of the rotating speed, the oil quantity and the cooling efficiency threshold comprises a plurality of historical rotating speeds and the historical oil quantity and the historical cooling efficiency threshold corresponding to each historical rotating speed; and determining the temperature threshold value corresponding to the current rotating speed and the current oil quantity through a one-to-one mapping relation of the rotating speed, the oil quantity and the cooled temperature threshold value, and obtaining the second preset threshold value, wherein the one-to-one mapping relation of the rotating speed, the oil quantity and the cooled temperature threshold value comprises a plurality of historical rotating speeds and the historical oil quantity and the historical temperature threshold value corresponding to each historical rotating speed. The method determines a first preset threshold value through the one-to-one mapping relation of the rotating speed, the oil quantity and the cooling efficiency threshold value, and determines a second preset threshold value through the one-to-one mapping relation of the rotating speed, the oil quantity and the cooled temperature threshold value, so that the first preset threshold value and the second preset threshold value can be accurately determined.

Specifically, the current rotating speed and the current oil quantity of the engine are obtained, a historical cooling efficiency threshold corresponding to the historical rotating speed and the historical oil quantity which are the same as the current rotating speed and the current oil quantity in a one-to-one mapping relation of the rotating speed, the oil quantity and the cooling efficiency threshold is used as a first preset threshold, and a historical temperature threshold corresponding to the historical rotating speed and the historical oil quantity which are the same as the current rotating speed and the current oil quantity in a one-to-one mapping relation of the rotating speed, the oil quantity and the cooled temperature threshold is used as a second preset threshold.

In order to make the calculation of the EGR cooling efficiency more accurate, the above step S201 may be implemented by: and under the condition that the current opening of the EGR valve is larger than or equal to 0 and the engine where the EGR system is positioned has no error, acquiring the gas temperature of the exhaust gas of the engine after being cooled by the EGR cooler, and obtaining the cooled temperature. The method obtains the cooled temperature and carries out subsequent judgment under the condition, so that the calculation of the cooling efficiency can be carried out under the condition, and the EGR cooling efficiency can be calculated more accurately.

In the specific implementation process, the calculation of the cooling efficiency of the EGR cooler is further performed only under the condition that the engine runs and has no related faults and the EGR rate or the EGR opening degree is greater than or equal to 0, the temperature after cooling is obtained, and the like, and if the engine is not in the running state under the conditions, for example, the engine is not in the running state, whether the EGR cooler is in fault or not is not required to be determined, or if the engine has reported to be in fault, the cooling efficiency of the EGR and whether the fault occurs or not are not required to be determined.

In order to enable those skilled in the art to more clearly understand the technical solutions of the present application, the implementation process of the control method of the EGR valve of the present application will be described in detail below with reference to specific embodiments.

The present embodiment relates to a control method of a specific EGR valve, fig. 4 is a schematic diagram of an engine device including an EGR valve, including an EGR cooler 3, a check valve 4, an EGR valve 5, an intake manifold 6, and an exhaust manifold 7, the EGR cooler 3 is provided with an EGR cooler front temperature sensor 1 and an EGR cooler rear temperature sensor 2, and fig. 5 is a flowchart of a control method of a specific EGR valve, including the steps of:

step S1: under the condition that the engine runs and has no relation to faults, and the EGR rate or the EGR opening (the current opening of the EGR valve) is more than or equal to 0, performing the next judgment;

step S2: acquiring a normal EGR cooler post temperature (post-cooling temperature) and a normal EGR cooler pre temperature (pre-cooler temperature), calculating cooling efficiency of the EGR cooler= (1-normal EGR cooler post temperature/normal pre-EGR cooler temperature), determining an EGR cooler efficiency threshold (a first preset threshold) corresponding to the current rotation speed and the current oil quantity according to the rotation speed, the oil quantity and an EGR cooler efficiency threshold MAP, wherein when the EGR cooler efficiency threshold is smaller than or equal to the EGR cooler efficiency threshold, after a delay time passes, the EGR cooler efficiency is low, error reporting (alarm signal), "/1/" indicates that "the EGR cooler efficiency is low, the" the EGR cooler efficiency is low, error reporting "does not satisfy the enabling condition when the EGR cooler efficiency threshold is larger than the EGR cooler efficiency threshold, and the rotation speed, the oil quantity and the EGR cooler efficiency threshold MAP are calibrated by experimental data such as the rotation speed, the oil quantity and the EGR cooler efficiency threshold in advance;

Step S3: when the EGR cooler efficiency is greater than an EGR cooler efficiency threshold (a first preset threshold), namely the EGR cooler efficiency does not meet the enabling condition of 'EGR cooler efficiency low error reporting', determining a maximum temperature threshold (a second preset threshold) corresponding to the current rotation speed and the oil quantity according to the rotation speed, the oil quantity and the maximum temperature threshold MAP, determining whether the temperature behind the normal EGR cooler is greater than or equal to the maximum temperature threshold (the second preset threshold), and when the temperature behind the normal EGR cooler is greater than or equal to the maximum temperature threshold, after the delay time, meeting the enabling condition of 'EGR cooler efficiency low error reporting', and then determining that the EGR cooler efficiency is low error reporting (an alarm signal);

step S4: determining a correction factor corresponding to the current EGR cooler post-temperature and the EGR exhaust gas amount according to the EGR cooler post-temperature, the EGR exhaust gas flow and the correction factor MAP, multiplying the correction factor and the EGR cooling efficiency by the EGR opening to obtain the EGR opening (target EGR valve opening), controlling the EGR valve to be the EGR opening (target EGR valve opening), multiplying the correction factor and the EGR cooling efficiency by the engine torque to obtain the engine torque (target torque), and controlling the engine to operate at the target torque when the condition that the EGR cooler efficiency threshold is less than or equal to the EGR cooler efficiency threshold is even enabled;

Step S5: under the condition that the temperature after the normal EGR cooler is more than or equal to the maximum temperature threshold value meets even energy conditions, multiplying the correction factor by the EGR opening to obtain the EGR opening, namely the target EGR valve opening is 0, and closing the EGR valve;

step S6: under the condition that the two conditions are met, namely the EGR cooler efficiency threshold value is less than or equal to the EGR cooler efficiency threshold value and the normal EGR cooler post-temperature is less than or equal to the maximum temperature threshold value, multiplying the correction factor and the EGR cooling efficiency by the EGR opening to obtain the EGR opening (target opening of the EGR valve), controlling the EGR valve to be the EGR opening (target opening of the EGR valve), and multiplying 0 and the correction factor by the engine torque to obtain the engine torque of 0, namely controlling the engine torque to be 0.

The embodiment of the application also provides a control device of the EGR valve, and the control device of the EGR valve can be used for executing the control method for the EGR valve. The device is used for realizing the above embodiments and preferred embodiments, and is not described in detail. As used below, the term "module" may be a combination of software and/or hardware that implements a predetermined function. While the means described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and contemplated.

The control device of the EGR valve provided in the embodiment of the present application is described below.

Fig. 6 is a schematic diagram of a control device of an EGR valve according to an embodiment of the present application. The EGR valve is included in an EGR system, and the EGR system further includes an EGR cooler and a check valve, and the EGR cooler, the check valve, and the EGR valve are sequentially connected in order, as shown in fig. 6, and the apparatus includes:

a first obtaining unit 10, configured to obtain a gas temperature of exhaust gas of an engine after the exhaust gas of the engine is cooled by the EGR cooler, obtain a cooled temperature, and obtain a current opening of the EGR valve, where the EGR system is included in the engine;

A first control unit 20 configured to calculate a cooling efficiency of the EGR cooler, obtain a correction factor when the cooling efficiency is less than or equal to a first preset threshold value, calculate a product of the cooling efficiency, the correction factor, and a current opening of the EGR valve to obtain an EGR valve target opening, and control the opening of the EGR valve to be the EGR valve target opening when the EGR valve target opening is different from the current opening of the EGR valve, wherein the correction factor is used to correct the opening of the EGR valve, and the cooling efficiency is an efficiency of the EGR cooler to cool exhaust gas of the engine;

And a second control unit 30 configured to control the EGR valve to be closed when the cooling efficiency is greater than the first preset threshold and the post-cooling temperature is greater than or equal to the second preset threshold.

In a specific implementation process, the first control unit comprises a first acquisition module and a first calculation module, wherein the first acquisition module is used for acquiring the gas temperature of the exhaust gas of the engine, which is not cooled by the EGR cooler, so as to obtain the temperature before cooling; the first calculating module is used for calculating the ratio of the temperature after cooling to the temperature before cooling, and calculating the difference between 1 and the ratio to obtain the cooling efficiency. According to the method, the cooling efficiency is obtained through calculation of the temperature before cooling and the temperature after cooling, so that the cooling efficiency can be accurately obtained through calculation, and whether the EGR cooler is in failure or not is determined through the cooling efficiency.

In order to accurately acquire correction factors so as to correct the opening of the EGR valve, the first control unit further comprises a second acquisition module and a determination module, wherein the second acquisition module is used for acquiring a plurality of historical cooled temperatures, a plurality of historical EGR valve flows, historical correction factors corresponding to each historical cooled temperature and each historical EGR valve flow, and obtaining a one-to-one mapping relation of the cooled temperatures, the EGR valve flows and the correction factors; the determining module is used for obtaining the current EGR valve flow, determining the historical correction factors corresponding to the cooled temperature and the current EGR valve flow according to the one-to-one mapping relation of the cooled temperature, the EGR valve flow and the correction factors, and obtaining the correction factors. According to the method, the historical correction factors are calibrated according to the temperature after historical cooling and the flow of the historical EGR valve, and the one-to-one mapping relation between the parameters is obtained, so that the correction factors corresponding to the current temperature after cooling and the current flow of the EGR valve can be determined through the one-to-one mapping relation.

The method further comprises a third control unit and a fourth control unit, wherein the third control unit is used for controlling the EGR cooler to generate an alarm signal to prompt the failure of the EGR cooler when the duration time of the cooling efficiency smaller than or equal to the first preset threshold value is larger than or equal to a first preset time period; and the fourth control unit is used for controlling the EGR cooler to generate the alarm signal to prompt the failure of the EGR cooler when the duration time of the cooling efficiency larger than the first preset threshold value is larger than or equal to a second preset time period and the duration time of the cooled temperature larger than or equal to the second preset threshold value is larger than or equal to the second preset time period. According to the method, under the condition that the cooling efficiency or the cooled temperature shows that the cooler is faulty, an alarm signal is generated to prompt the fault of the EGR cooler, prompt a driver to troubleshoot the fault, and ensure the safety of an EGR system and the stability of an engine or emission of a subsequent vehicle.

In order to limit the torque of the engine in time in case of failure of the EGR cooler, to avoid causing the failure of the engine, in some embodiments, the above-mentioned apparatus further comprises a second obtaining unit, a fifth control unit and a sixth control unit, wherein the current torque of the above-mentioned engine is obtained, wherein the second obtaining unit is used for the above-mentioned EGR system to be included in the above-mentioned engine; a fifth control unit configured to calculate a product of the cooling efficiency, the correction factor, and the current torque to obtain a target torque, and control the engine to operate at the target torque, when the cooling efficiency is less than or equal to the first preset threshold; and the sixth control unit is used for controlling the rotating speed of the engine to be idle when the temperature after cooling is greater than or equal to the second preset threshold value. The method also corrects the engine torque through the correction factors, so that the EGR opening degree can be limited and the EGR torque can be limited at the same time under the condition of the failure of the EGR cooler, thereby avoiding the failure of an EGR valve and the engine.

In some optional embodiments, the control method further includes a third acquiring unit, a first determining unit, and a second determining unit, where the third acquiring unit is configured to acquire the current rotation speed and the current oil amount of the engine; the first determining unit is configured to determine a cooling efficiency threshold corresponding to the current rotation speed and the current oil amount according to a one-to-one mapping relationship between the rotation speed, the oil amount and the cooling efficiency threshold, so as to obtain the first preset threshold, where the one-to-one mapping relationship between the rotation speed, the oil amount and the cooling efficiency threshold includes a plurality of historical rotation speeds and the historical oil amount and the historical cooling efficiency threshold corresponding to each historical rotation speed; the first determining unit is configured to determine a temperature threshold corresponding to the current rotation speed and the current oil amount according to a one-to-one mapping relationship between the rotation speed, the oil amount and the cooled temperature threshold, and obtain the second preset threshold, where the one-to-one mapping relationship between the rotation speed, the oil amount and the cooled temperature threshold includes a plurality of historical rotation speeds and the historical oil amount and the historical temperature threshold corresponding to each of the historical rotation speeds. The method determines a first preset threshold value through the one-to-one mapping relation of the rotating speed, the oil quantity and the cooling efficiency threshold value, and determines a second preset threshold value through the one-to-one mapping relation of the rotating speed, the oil quantity and the cooled temperature threshold value, so that the first preset threshold value and the second preset threshold value can be accurately determined.

In order to make the calculation of the EGR cooling efficiency more accurate, the first obtaining unit includes a third obtaining module configured to obtain the gas temperature of the exhaust gas of the engine after the exhaust gas of the engine is cooled by the EGR cooler, to obtain the cooled temperature, when the current opening of the EGR valve is greater than or equal to 0 and the engine where the EGR system is located has no error. The method obtains the cooled temperature and carries out subsequent judgment under the condition, so that the calculation of the cooling efficiency can be carried out under the condition, and the EGR cooling efficiency can be calculated more accurately.

The control device of the EGR valve comprises a processor and a memory, wherein the first acquisition unit, the first control unit, the second control unit and the like are stored in the memory as program units, and the processor executes the program units stored in the memory to realize corresponding functions. The modules are all located in the same processor; alternatively, the above modules may be located in different processors in any combination.

The processor includes a kernel, and the kernel fetches the corresponding program unit from the memory. The inner core can be provided with one or more than one, and the problem of burning and melting of the EGR valve is solved by adjusting the parameters of the inner core.

The memory may include volatile memory, random Access Memory (RAM), and/or nonvolatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM), among other forms in computer readable media, the memory including at least one memory chip.

The embodiment of the invention provides a computer readable storage medium, which comprises a stored program, wherein the control method for controlling equipment where the computer readable storage medium is located to execute the EGR valve is controlled by the program.

Specifically, the control method of the EGR valve includes:

Optionally, calculating the cooling efficiency of the EGR cooler includes: acquiring the temperature of the exhaust gas of the engine which is not cooled by the EGR cooler, and obtaining the temperature before cooling; and calculating the ratio of the temperature after cooling to the temperature before cooling, and calculating the difference between 1 and the ratio to obtain the cooling efficiency.

Optionally, obtaining the correction factor includes: acquiring a plurality of historical cooling temperatures, a plurality of historical EGR valve flows, each historical cooling temperature and a historical correction factor corresponding to each historical EGR valve flow, and obtaining a one-to-one mapping relation of the cooled temperatures, the EGR valve flows and the correction factors; and acquiring the current EGR valve flow, and determining a historical correction factor corresponding to the cooled temperature and the current EGR valve flow according to the one-to-one mapping relation of the cooled temperature, the EGR valve flow and the correction factor to obtain the correction factor.

Optionally, in a case where the cooling efficiency is less than or equal to a first preset threshold or the cooling efficiency is greater than the first preset threshold and the post-cooling temperature is greater than or equal to the second preset threshold, the control method further includes: controlling the EGR cooler to generate an alarm signal to prompt the failure of the EGR cooler when the duration of the cooling efficiency being less than or equal to the first preset threshold is greater than or equal to a first preset time period; and controlling the EGR cooler to generate the alarm signal to prompt the failure of the EGR cooler when the duration of the cooling efficiency being greater than the first preset threshold value is greater than or equal to a second preset time period and the duration of the cooled temperature being greater than or equal to the second preset threshold value is greater than or equal to the second preset time period.

Optionally, the control method further includes: acquiring the current torque of the engine, wherein the EGR system is contained in the engine; calculating a product of the cooling efficiency, the correction factor, and the current torque to obtain a target torque, and controlling the engine to operate at the target torque when the cooling efficiency is less than or equal to the first preset threshold; and controlling the rotation speed of the engine to be idle under the condition that the temperature after cooling is greater than or equal to the second preset threshold value.

Optionally, the control method further includes: acquiring the current rotating speed and the current oil quantity of the engine; determining a cooling efficiency threshold corresponding to the current rotating speed and the current oil quantity through a one-to-one mapping relation of the rotating speed, the oil quantity and the cooling efficiency threshold to obtain the first preset threshold, wherein the one-to-one mapping relation of the rotating speed, the oil quantity and the cooling efficiency threshold comprises a plurality of historical rotating speeds and the historical oil quantity and the historical cooling efficiency threshold corresponding to each historical rotating speed; and determining the temperature threshold value corresponding to the current rotating speed and the current oil quantity through a one-to-one mapping relation of the rotating speed, the oil quantity and the cooled temperature threshold value, and obtaining the second preset threshold value, wherein the one-to-one mapping relation of the rotating speed, the oil quantity and the cooled temperature threshold value comprises a plurality of historical rotating speeds and the historical oil quantity and the historical temperature threshold value corresponding to each historical rotating speed.

Optionally, obtaining a gas temperature of exhaust gas of the engine after cooling by the EGR cooler, to obtain a cooled temperature, including: and under the condition that the current opening of the EGR valve is larger than or equal to 0 and the engine where the EGR system is positioned has no error, acquiring the gas temperature of the exhaust gas of the engine after being cooled by the EGR cooler, and obtaining the cooled temperature.

The embodiment of the invention provides equipment, which comprises a processor, a memory and a program stored in the memory and capable of running on the processor, wherein the processor realizes at least the following steps when executing the program:

The device herein may be a server, PC, PAD, cell phone, etc.

The present application also provides a computer program product adapted to perform a program initialized with at least the following method steps when executed on a data processing device:

It will be appreciated by those skilled in the art that the modules or steps of the invention described above may be implemented in a general purpose computing device, they may be concentrated on a single computing device, or distributed across a network of computing devices, they may be implemented in program code executable by computing devices, so that they may be stored in a storage device for execution by computing devices, and in some cases, the steps shown or described may be performed in a different order than that shown or described herein, or they may be separately fabricated into individual integrated circuit modules, or multiple modules or steps of them may be fabricated into a single integrated circuit module. Thus, the present invention is not limited to any specific combination of hardware and software.

It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

In one typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include volatile memory in a computer-readable medium, random Access Memory (RAM) and/or nonvolatile memory, etc., such as Read Only Memory (ROM) or flash RAM. Memory is an example of a computer-readable medium.

Computer readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of storage media for a computer include, but are not limited to, phase change memory (PRAM), static Random Access Memory (SRAM), dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), read Only Memory (ROM), electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium, which can be used to store information that can be accessed by a computing device. Computer-readable media, as defined herein, does not include transitory computer-readable media (transmission media), such as modulated data signals and carrier waves.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article or apparatus that comprises an element.

From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

1) According to the control method of the EGR valve, the cooled temperature of the EGR cooler and the current opening of the EGR valve in the EGR system are obtained, the cooling efficiency of the EGR cooler is calculated, and under the condition that the cooling efficiency is smaller than a first preset threshold value, the product of the cooling efficiency, the correction factor and the current opening of the EGR valve is calculated, so that the target opening of the EGR valve is obtained; and controlling the EGR valve to be closed under the condition that the cooling efficiency is larger than a first preset threshold value and the cooled temperature is larger than a second preset threshold value. Therefore, through monitoring the cooling efficiency and the temperature after cooling of the EGR cooler, when the cooling efficiency of the EGR is low or the temperature after cooling is too high, the circulation of exhaust gas of the EGR valve can be timely reduced or interrupted, and the EGR valve is prevented from being burnt due to hot gas impact. Compared with the prior art, after the fault of the EGR cooler, the high-temperature EGR waste flow still flows through the EGR valve, and the EGR valve is burnt and melted, the high-temperature waste flow of the EGR valve is timely reduced or interrupted, the problems of further burnt and melted of the EGR valve or damage and the like are avoided, and therefore the problem that the burnt and melted of the EGR valve is caused by high-temperature waste gas in the prior art can be solved.

2) In the control device of the EGR valve, the cooled temperature of the EGR cooler and the current opening of the EGR valve in the EGR system are obtained, the cooling efficiency of the EGR cooler is calculated, and under the condition that the cooling efficiency is smaller than a first preset threshold value, the product of the cooling efficiency, the correction factor and the current opening of the EGR valve is calculated to obtain the target opening of the EGR valve; and controlling the EGR valve to be closed under the condition that the cooling efficiency is larger than a first preset threshold value and the cooled temperature is larger than a second preset threshold value. Therefore, through monitoring the cooling efficiency and the temperature after cooling of the EGR cooler, when the cooling efficiency of the EGR is low or the temperature after cooling is too high, the circulation of exhaust gas of the EGR valve can be timely reduced or interrupted, and the EGR valve is prevented from being burnt due to hot gas impact. Compared with the prior art, after the fault of the EGR cooler, the high-temperature EGR waste flow still flows through the EGR valve, and the EGR valve is burnt and melted, the high-temperature waste flow of the EGR valve is timely reduced or interrupted, the problems of further burnt and melted of the EGR valve or damage and the like are avoided, and therefore the problem that the burnt and melted of the EGR valve is caused by high-temperature waste gas in the prior art can be solved.

The foregoing description is only of the preferred embodiments of the present application and is not intended to limit the same, but rather, various modifications and variations may be made by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. The control method of the EGR valve is characterized in that the EGR valve is contained in an EGR system, the EGR system further comprises an EGR cooler and a check valve, and the EGR cooler, the check valve and the EGR valve are sequentially connected in sequence and comprise the following steps:

acquiring the gas temperature of the exhaust gas of the engine after being cooled by the EGR cooler, obtaining the cooled temperature, and acquiring the current opening of the EGR valve to obtain the current opening of the EGR valve, wherein the EGR system is contained in the engine;

calculating cooling efficiency of the EGR cooler, obtaining a correction factor when the cooling efficiency is smaller than or equal to a first preset threshold value, calculating a product of the cooling efficiency, the correction factor and the current opening of the EGR valve to obtain an EGR valve target opening, and controlling the opening of the EGR valve to be the EGR valve target opening when the EGR valve target opening is different from the current opening of the EGR valve, wherein the correction factor is used for correcting the opening of the EGR valve, and the cooling efficiency is the efficiency of the EGR cooler for cooling exhaust gas of the engine;

and controlling the EGR valve to be closed under the condition that the cooling efficiency is greater than the first preset threshold value and the cooled temperature is greater than or equal to a second preset threshold value.

2. The control method according to claim 1, characterized in that calculating the cooling efficiency of the EGR cooler comprises:

acquiring the temperature of the gas of the exhaust gas of the engine which is not cooled by the EGR cooler, and obtaining the temperature before cooling;

and calculating the ratio of the temperature after cooling to the temperature before cooling, and calculating the difference between 1 and the ratio to obtain the cooling efficiency.

3. The control method according to claim 1, characterized in that acquiring the correction factor includes:

acquiring a plurality of historical cooled temperatures, a plurality of historical EGR valve flows, each historical cooled temperature and a historical correction factor corresponding to each historical EGR valve flow, and obtaining a one-to-one mapping relation of the cooled temperatures, the EGR valve flows and the correction factors;

and acquiring the current EGR valve flow, determining the historical correction factors corresponding to the cooled temperature and the current EGR valve flow according to the one-to-one mapping relation of the cooled temperature, the EGR valve flow and the correction factors, and obtaining the correction factors.

4. The control method according to claim 1, characterized in that in the case where the cooling efficiency is less than or equal to a first preset threshold value or where the cooling efficiency is greater than the first preset threshold value and the post-cooling temperature is greater than or equal to the second preset threshold value, the control method further comprises:

Controlling the EGR cooler to generate an alarm signal to prompt the failure of the EGR cooler when the duration of the cooling efficiency less than or equal to the first preset threshold is greater than or equal to a first preset time period;

and controlling the EGR cooler to generate the alarm signal to prompt the failure of the EGR cooler under the condition that the duration time of the cooling efficiency being greater than the first preset threshold value is greater than or equal to a second preset time period and the duration time of the cooled temperature being greater than or equal to the second preset threshold value is greater than or equal to the second preset time period.

5. The control method according to claim 1, characterized in that the control method further comprises:

acquiring the current torque of the engine, wherein the EGR system is contained in the engine;

calculating the product of the cooling efficiency, the correction factor and the current torque to obtain a target torque under the condition that the cooling efficiency is smaller than or equal to the first preset threshold value, and controlling the engine to run at the target torque;

and controlling the rotating speed of the engine to be idle under the condition that the temperature after cooling is greater than or equal to the second preset threshold value.

6. The control method according to claim 1, characterized in that the control method further comprises:

acquiring the current rotating speed and the current oil quantity of the engine;

determining a cooling efficiency threshold corresponding to the current rotating speed and the current oil quantity through a one-to-one mapping relation of the rotating speed, the oil quantity and the cooling efficiency threshold to obtain the first preset threshold, wherein the one-to-one mapping relation of the rotating speed, the oil quantity and the cooling efficiency threshold comprises a plurality of historical rotating speeds and historical oil quantity and historical cooling efficiency thresholds corresponding to each historical rotating speed;

and determining the temperature threshold corresponding to the current rotating speed and the current oil quantity through a one-to-one mapping relation of the rotating speed, the oil quantity and the cooled temperature threshold, and obtaining the second preset threshold, wherein the one-to-one mapping relation of the rotating speed, the oil quantity and the cooled temperature threshold comprises a plurality of historical rotating speeds and the historical oil quantity and the historical temperature threshold corresponding to each historical rotating speed.

7. The control method according to claim 1, characterized in that obtaining a gas temperature of exhaust gas of the engine after cooling by the EGR cooler, obtaining a cooled temperature, comprises:

and under the conditions that the current opening of the EGR valve is larger than or equal to 0 and the engine where the EGR system is positioned has no error, acquiring the gas temperature of the exhaust gas of the engine after the exhaust gas is cooled by the EGR cooler, and obtaining the cooled temperature.

8. The control device of the EGR valve is characterized in that the EGR valve is contained in an EGR system, the EGR system further comprises an EGR cooler and a check valve, and the EGR cooler, the check valve and the EGR valve are sequentially connected in sequence and comprise:

a first obtaining unit, configured to obtain a gas temperature of exhaust gas of an engine after the exhaust gas passes through the EGR cooler to obtain a cooled temperature, and obtain a current opening of the EGR valve to obtain a current opening of the EGR valve, where the EGR system is included in the engine;

a first control unit, configured to calculate a cooling efficiency of the EGR cooler, obtain a correction factor when the cooling efficiency is less than or equal to a first preset threshold, calculate a product of the cooling efficiency, the correction factor, and a current opening of the EGR valve, obtain an EGR valve target opening, and control the opening of the EGR valve to be the EGR valve target opening when the EGR valve target opening is different from the EGR valve current opening, where the correction factor is used to correct the opening of the EGR valve, and the cooling efficiency is an efficiency of the EGR cooler to cool exhaust gas of the engine;

and the second control unit is used for controlling the EGR valve to be closed under the condition that the cooling efficiency is larger than the first preset threshold value and the cooled temperature is larger than or equal to a second preset threshold value.

9. A computer-readable storage medium, characterized in that the computer-readable storage medium includes a stored program, wherein the program, when run, controls a device in which the computer-readable storage medium is located to execute the control method according to any one of claims 1 to 7.

10. An electronic device, comprising: one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs comprising instructions for performing the control method of any of claims 1-7.