A method and device for determining consistency of engine intake system

Abstract

The present application discloses a method and device for determining the consistency of an engine intake system. When the engine is in steady-state operation, a first calculation method can be used to calculate the first gas flow rate of a first subsystem in the engine intake system, and a second calculation method can be used to calculate the second gas flow rate of the first subsystem. The first calculation method uses the principle of conservation of energy, and the accuracy of the second calculation method is affected by the consistency of zero components. Then, the deviation between the first gas flow rate and the second gas flow rate is determined, and the consistency of the first subsystem is determined based on the deviation. It can be seen that the consistency of the first subsystem in the engine intake system can be determined by using this solution. Correspondingly, if this solution is used for each subsystem, the consistency of the engine intake system can be determined.

Description

Technical Field

[0001] The present application relates to the field of vehicles, and in particular to a method and device for determining the consistency of an engine intake system. Background Art

[0002] The consistency of components in a vehicle directly affects engine reliability. Small changes in the size of key components can cause significant changes in performance. If there is a consistency problem in the intake system, the accurate air-fuel ratio cannot be obtained, which will lead to excessive emissions. Among them, the consistency problem of the intake system may be the consistency problem of the components in the intake system (for example, the actual size is inconsistent with the theoretical size).

[0003] Therefore, how to determine the consistency of the engine intake system is an issue that needs to be solved urgently. Summary of the invention

[0004] The technical problem to be solved by the present application is how to determine the consistency of an engine intake system, and to provide a method and device for determining the consistency of an engine intake system.

[0005] In a first aspect, an embodiment of the present application provides a method for determining consistency of an engine intake system, the method comprising:

[0006] When the engine is running in a steady state, a first gas flow rate of a first subsystem in the engine intake system is calculated by a first calculation method, and a second gas flow rate of the first subsystem is calculated by a second calculation method, wherein the first calculation method adopts the energy conservation principle, and the accuracy of the second calculation method is affected by the consistency of zero components;

[0007] determining a deviation between the first gas flow rate and the second gas flow rate;

[0008] Based on the deviation, consistency of the first subsystem is determined.

[0009] Optionally, the first subsystem includes any one of the following:

[0010] Air subsystem, fuel gas subsystem and exhaust gas recirculation (EGR) subsystem.

[0011] Optionally, the energy conservation principle includes:

[0012] The sum of air energy change, fuel gas energy change, exhaust gas recirculation EGR energy change and heat exchange energy is 0, where:

[0013] The air energy change is determined based on the air flow rate, the temperature of the mixed gas in the engine intake pipe, the specific heat capacity of the air at the temperature of the mixed gas, the temperature of the air, and the specific heat capacity of the air at the temperature of the air;

[0014] The gas energy change is determined according to the gas flow rate, the temperature of the mixed gas, the specific heat capacity of the gas at the temperature of the mixed gas, the temperature of the gas, and the specific heat capacity of the gas at the temperature of the gas;

[0015] The EGR energy change is determined according to the EGR flow rate, the temperature of the mixed gas, the specific heat capacity of the EGR gas at the temperature of the mixed gas, the temperature of the EGR gas, and the specific heat capacity of the EGR gas at the temperature of the EGR gas;

[0016] The heat exchange energy is determined based on the surface area of ​​the engine intake system, the convective heat transfer coefficient, the convective heat transfer correction coefficient, the temperature of the mixed gas, and the ambient temperature. The heat exchange energy is the energy for heat exchange between the engine intake system and the environment.

[0017] Optionally, the second calculation method includes any one of the following:

[0018] Flow meter calculation method, Venturi method calculation method, pressure difference method calculation method, speed density method calculation method.

[0019] Optionally, the method further includes:

[0020] In the case where there is a consistency problem in the first subsystem, vehicle fault diagnosis information is obtained, and a fault cause of the first subsystem is determined according to the vehicle fault diagnosis information.

[0021] In a second aspect, an embodiment of the present application provides a device for determining consistency of an engine intake system, the device comprising:

[0022] a calculation unit, configured to calculate, when the engine is in steady-state operation, a first gas flow rate of a first subsystem in an engine intake system by a first calculation method, and calculate a second gas flow rate of the first subsystem by a second calculation method, wherein the first calculation method adopts the energy conservation principle, and the accuracy of the second calculation method is affected by the consistency of zero components;

[0023] a first determining unit, configured to determine a deviation between the first gas flow rate and the second gas flow rate;

[0024] The second determining unit is configured to determine the consistency of the first subsystem according to the deviation.

[0025] Optionally, the first subsystem includes any one of the following:

[0026] Air subsystem, fuel gas subsystem and exhaust gas recirculation (EGR) subsystem.

[0027] Optionally, the energy conservation principle includes:

[0028] The sum of air energy change, fuel gas energy change, exhaust gas recirculation EGR energy change and heat exchange energy is 0, where:

[0029] The air energy change is determined based on the air flow rate, the temperature of the mixed gas in the engine intake pipe, the specific heat capacity of the air at the temperature of the mixed gas, the temperature of the air, and the specific heat capacity of the air at the temperature of the air;

[0030] The gas energy change is determined according to the gas flow rate, the temperature of the mixed gas, the specific heat capacity of the gas at the temperature of the mixed gas, the temperature of the gas, and the specific heat capacity of the gas at the temperature of the gas;

[0031] The EGR energy change is determined according to the EGR flow rate, the temperature of the mixed gas, the specific heat capacity of the EGR gas at the temperature of the mixed gas, the temperature of the EGR gas, and the specific heat capacity of the EGR gas at the temperature of the EGR gas;

[0032] The heat exchange energy is determined based on the surface area of ​​the engine intake system, the convective heat transfer coefficient, the convective heat transfer correction coefficient, the temperature of the mixed gas, and the ambient temperature. The heat exchange energy is the energy for heat exchange between the engine intake system and the environment.

[0033] Optionally, the second calculation method includes any one of the following:

[0034] Flow meter calculation method, Venturi method calculation method, pressure difference method calculation method, speed density method calculation method.

[0035] Optionally, the device further comprises:

[0036] The processing unit is used to obtain vehicle fault diagnosis information when there is a consistency problem in the first subsystem, and determine the cause of the fault of the first subsystem according to the vehicle fault diagnosis information.

[0037] In a third aspect, an embodiment of the present application provides a device, comprising: a processor, a memory, and a system bus; the processor and the memory are connected via the system bus; the memory is used to store one or more programs, and the one or more programs include instructions, which, when executed by the processor, enable the processor to execute any one of the methods described in the first aspect above.

[0038] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein instructions are stored in the computer-readable storage medium. When the instructions are executed on a terminal device, the terminal device executes any of the methods described in the first aspect above.

[0039] Compared with the prior art, the embodiments of the present application have the following advantages:

[0040] The embodiment of the present application provides a method for determining the consistency of an engine intake system. In one example, when the engine is in steady-state operation, a first calculation method can be used to calculate the first gas flow of a first subsystem in the engine intake system, and a second calculation method can be used to calculate the second gas flow of the first subsystem. The first calculation method adopts the principle of conservation of energy, and the accuracy of the second calculation method is affected by the consistency of zero components. Then, the deviation between the first gas flow and the second gas flow is determined, and the consistency of the first subsystem is determined based on the deviation. Since the first calculation method adopts the principle of conservation of energy, the first gas flow can be considered to be relatively stable and reliable. Accordingly, the accuracy of the second gas flow can be measured based on the deviation between the first gas flow and the second gas flow, and the accuracy of the second calculation method is affected by the consistency of zero components. Therefore, based on the deviation, the consistency of the first subsystem can be determined. It can be seen that the consistency of the first subsystem in the engine intake system can be determined by using this solution. Accordingly, if this solution is used for each subsystem, the consistency of the engine intake system can be determined. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 A flow chart of a method for determining consistency of an engine intake system provided in an embodiment of the present application;

[0043] Figure 2 A schematic diagram of the structure of an engine intake system provided in an embodiment of the present application;

[0044] Figure 3 A schematic diagram of the structure of a device for determining the consistency of an engine intake system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0046] Various non-limiting implementations of the present application are described in detail below in conjunction with the accompanying drawings.

[0047] Exemplary Methods

[0048] See also Figure 1 , which is a flow chart of a method for determining consistency of an engine intake system provided by an embodiment of the present application. In this embodiment, the method may include the following steps: S101-S103.

[0049] S101: When the engine is running in a steady state, a first calculation method is used to calculate a first gas flow rate of a first subsystem in the engine intake system, and a second calculation method is used to calculate a second gas flow rate of the first subsystem. The first calculation method uses the principle of conservation of energy, and the accuracy of the second calculation method is affected by the consistency of zero components.

[0050] In the embodiment of the present application, when the engine meets the following conditions, it can be considered that the engine is operating in a steady state.

[0051] 1. Stable operating conditions, such as no sudden acceleration or deceleration, no parking, no reverse towing, etc.

[0052] 2. The minimum running time of the engine is greater than the first time, and the engine water temperature and oil temperature meet certain conditions to ensure that the engine is in a non-warm-up state;

[0053] 3. The sensors related to flow calculation are not faulty.

[0054] Regarding the engine intake system, it can be combined with Figure 2 To understand, Figure 2 FIG. 1 shows a schematic diagram of the structure of an engine intake system. Figure 2 As shown, the engine intake system 200 includes three types of intake ports, namely: air intake port 201, fuel gas intake port 202 and exhaust gas recirculation (EGR) intake port 203. After these three gases enter the intake system 200, a mixed gas is obtained. Figure 2The intake system shown may include: an air subsystem, a gas subsystem and an EGR subsystem. The first subsystem may be any one of the air subsystem, the gas subsystem and the EGR subsystem.

[0055] When the first subsystem is an air subsystem, the first gas flow rate is the air flow rate calculated by a first calculation method, and the second gas flow rate is the air flow rate calculated by a second calculation method;

[0056] When the first subsystem is a gas subsystem, the first gas flow is the gas flow calculated by a first calculation method, and the second gas flow is the gas flow calculated by a second calculation method;

[0057] When the first subsystem is an EGR subsystem, the first gas flow is an EGR flow calculated by a first calculation method, and the second gas flow is an EGR flow calculated by a second calculation method.

[0058] Regarding the energy conservation principle, it should be noted that, in one example, the energy conservation principle can be reflected as follows: the sum of air energy change, fuel gas energy change, exhaust gas recirculation EGR energy change and heat exchange energy is 0. That is, it is reflected as the following formula (1):

[0059] ΔQ Air +ΔQ Fuel +ΔQ EGR +ΔQ HT =0 Formula (1)

[0060] In formula (1):

[0061] ΔQ Air For air energy changes;

[0062] ΔQ Fuel The energy change of gas;

[0063] ΔQ EGR The EGR energy changes are:

[0064] ΔQ HT It is heat exchange energy, wherein the heat exchange energy is the energy of heat exchange between the intake system of the engine and the environment.

[0065] In one example, the air energy change is determined based on the air flow rate, the temperature of the mixed gas in the engine intake pipe, the specific heat capacity of the air at the temperature of the mixed gas, the temperature of the air, and the specific heat capacity of the air at the temperature of the air. As an example, the air energy change can be calculated by the following formula (2).

[0066] ΔQAir =m Air *[C p1 (T Mix )*T Mix -C p1 (T Air )*T Air ] Formula (2)

[0067] In formula (2):

[0068] ΔQ Air For air energy changes;

[0069] m Air is the air flow rate in kilograms per second (kg / s);

[0070] T Mix is the temperature of the mixed gas in the engine intake pipe, and its value can be measured by a sensor;

[0071] C p1 (T Mix ) is the constant-pressure specific heat capacity of air at the temperature of the mixed gas, which can be calculated if the temperature of the mixed gas is known;

[0072] T Air is the temperature of the air, and its value can be measured by a sensor;

[0073] C p1 (T Air ) is the constant-pressure specific heat capacity of air at the temperature of the air, which can be calculated when the temperature of the air is known.

[0074] In one example, the gas energy change is determined based on the gas flow rate, the temperature of the mixed gas, the specific heat capacity of the gas at the temperature of the mixed gas, the temperature of the gas, and the specific heat capacity of the gas at the temperature of the gas. As an example, the gas energy change can be calculated by the following formula (3).

[0075] ΔQ Fuel =m Fuel *[C p2 (T Mix )*T Mix -C p2 (T Fuel )*T Fuel ] Formula (3)

[0076] In formula (3):

[0077] △Q Fuel is the gas energy change;

[0078] m Fuelis the gas flow rate, in kg / s;

[0079] T Mix is the temperature of the mixed gas;

[0080] C p2 (T Mix ) is the constant-pressure specific heat capacity of the fuel gas at the temperature of the mixed gas. If the temperature of the mixed gas is known, this value can be calculated;

[0081] T Fuel is the temperature of the gas, and its value can be measured by a sensor;

[0082] C p2 (T Fuel ) is the constant-pressure specific heat capacity of the gas at the gas temperature. This value can be calculated if the gas temperature is known.

[0083] In one example, the EGR energy change is determined based on the EGR flow rate, the temperature of the mixed gas, the specific heat capacity of the EGR gas at the temperature of the mixed gas, the temperature of the EGR gas, and the specific heat capacity of the EGR gas at the temperature of the EGR gas. As an example, the EGR energy change can be calculated by the following formula (4).

[0084] ΔQ EGR =m EGR *[C p3 (T Mix )*T Mix -C p3 (T EGR )*T EGR ] Formula (4)

[0085] In formula (4):

[0086] ΔQ EGR is the EGR energy change;

[0087] m EGR is the EGR flow rate, in kg / s;

[0088] T Mix is the temperature of the mixed gas;

[0089] C p3 (T Mix ) is the constant-pressure specific heat capacity of the EGR gas at the temperature of the mixed gas, and this value can be calculated when the temperature of the mixed gas is known;

[0090] T EGR is the temperature of the EGR gas, and its value can be measured by a sensor;

[0091] Cp3 (T EGR ) is the constant-pressure specific heat capacity of the EGR gas at the temperature of the EGR gas, and this value can be calculated when the temperature of the EGR gas is known.

[0092] In one example, the heat exchange energy is determined according to a surface area of ​​an intake system of the engine, a convection heat transfer coefficient, a convection heat transfer correction coefficient, a temperature of the mixed gas, and an ambient temperature.

[0093] As an example, the heat exchange energy can be calculated by the following formula (5).

[0094]

[0095] In formula (5):

[0096] ΔQ HT For heat transfer energy:

[0097] A s is the surface area of ​​the engine intake system, which is a known value;

[0098] H is the convective heat transfer coefficient between the intake system and the environment;

[0099] is the convective heat transfer correction coefficient, which can be calibrated based on factors such as vehicle speed, engine speed, and mixture pressure, and is a known value;

[0100] T Mix is the temperature of the mixed gas, and its value can be measured by a sensor;

[0101] T0 is the ambient temperature, and its value can be measured by a sensor.

[0102] From the above formulas (1) to (5), we can see that when m Air 、m Fuel 、m EGR If any two variables in are taken as known values ​​(for example, the values ​​calculated by the second calculation method or the third calculation method), the value of the other variable can be calculated by the energy balance formula, based on which the air flow rate, gas flow rate and EGR flow rate can be respectively obtained.

[0103] Regarding the second calculation method, it should be noted that the second calculation method can be any one of the flow meter calculation method, the Venturi method calculation method, the pressure difference method calculation method, and the speed density method calculation method. The flow meter calculation method, the Venturi method calculation method, the pressure difference method calculation method, and the speed density method calculation method are not described in detail here.

[0104] Regarding the third calculation method mentioned above, it should be noted that the third calculation method is similar to the second calculation method, and can also be one of the flow meter calculation method, the Venturi method calculation method, the pressure difference method calculation method, and the velocity density method calculation method. The third calculation method can be the same as or different from the second calculation method.

[0105] S102: Determine a deviation between the first gas flow rate and the second gas flow rate.

[0106] In one example, the deviation can be calculated using the following formula (6) or formula (7).

[0107]

[0108] In formula (6) and formula (7):

[0109] m1 is the first gas flow rate;

[0110] m2 is the flow rate of the second gas.

[0111] S103: Determine the consistency of the first subsystem according to the deviation.

[0112] In the specific implementation of S103, the consistency of the first subsystem can be determined based on the deviation and the preset threshold. When the deviation is less than the preset threshold, it is determined that there is no consistency problem in the first subsystem. When the deviation is greater than or equal to the preset threshold, it is determined that there is a consistency problem in the first subsystem. The preset threshold mentioned here can be a smaller value, and the specific value is not limited here.

[0113] From the above description, it can be known that since the first calculation method adopts the principle of conservation of energy, the first gas flow rate can be considered to be relatively stable and reliable. Accordingly, the accuracy of the second gas flow rate can be measured according to the deviation between the first gas flow rate and the second gas flow rate, and the accuracy of the second calculation method is affected by the consistency of the components in the first subsystem. Therefore, based on the deviation, the consistency of the first subsystem can be determined. For example, if the deviation indicates that the accuracy of the second gas flow rate is high, the possibility that the first subsystem has a consistency problem is low. Correspondingly, if the deviation indicates that the accuracy of the second gas flow rate is low, the possibility that the first subsystem has a consistency problem is high. It can be seen that, using this solution, the consistency of the first subsystem in the engine intake system can be determined. Correspondingly, if this solution is used for each subsystem, the consistency of the engine intake system can be determined.

[0114] In one example, if after executing S101-S103, it is determined that the first subsystem has a consistency problem, vehicle fault diagnosis information can be further obtained, and the fault cause of the first subsystem can be determined based on the vehicle fault diagnosis information. The vehicle fault diagnosis information mentioned here can be fault diagnosis information output by an on board diagnostics (OBD) system, and the fault diagnosis information includes but is not limited to supercharger correction status information, air-fuel ratio self-learning value, and EGR valve correction status information.

[0115] Exemplary Devices

[0116] Based on the method provided in the above embodiment, the embodiment of the present application further provides a device, which is described below in conjunction with the accompanying drawings.

[0117] See also Figure 3 , Figure 3 The schematic diagram of the structure of a device for determining the consistency of an engine intake system provided in an embodiment of the present application is as follows: the device 300 may specifically include: a calculation unit 301 , a first determination unit 302 , and a second determination unit 303 .

[0118] The calculation unit 301 is used to calculate the first gas flow of a first subsystem in the engine intake system by a first calculation method when the engine is running in a steady state, and calculate the second gas flow of the first subsystem by a second calculation method, wherein the first calculation method adopts the energy conservation principle, and the accuracy of the second calculation method is affected by the consistency of zero components;

[0119] A first determining unit 302, configured to determine a deviation between the first gas flow rate and the second gas flow rate;

[0120] The second determining unit 303 is configured to determine the consistency of the first subsystem according to the deviation.

[0121] Optionally, the first subsystem includes any one of the following:

[0122] Air subsystem, fuel gas subsystem and exhaust gas recirculation (EGR) subsystem.

[0123] Optionally, the energy conservation principle includes:

[0124] The sum of air energy change, fuel gas energy change, exhaust gas recirculation EGR energy change and heat exchange energy is 0, where:

[0125] The air energy change is determined based on the air flow rate, the temperature of the mixed gas in the engine intake pipe, the specific heat capacity of the air at the temperature of the mixed gas, the temperature of the air, and the specific heat capacity of the air at the temperature of the air;

[0126] The gas energy change is determined according to the gas flow rate, the temperature of the mixed gas, the specific heat capacity of the gas at the temperature of the mixed gas, the temperature of the gas, and the specific heat capacity of the gas at the temperature of the gas;

[0127] The EGR energy change is determined according to the EGR flow rate, the temperature of the mixed gas, the specific heat capacity of the EGR gas at the temperature of the mixed gas, the temperature of the EGR gas, and the specific heat capacity of the EGR gas at the temperature of the EGR gas;

[0128] The heat exchange energy is determined based on the surface area of ​​the engine intake system, the convective heat transfer coefficient, the convective heat transfer correction coefficient, the temperature of the mixed gas, and the ambient temperature. The heat exchange energy is the energy for heat exchange between the engine intake system and the environment.

[0129] Optionally, the second calculation method includes any one of the following:

[0130] Flow meter calculation method, Venturi method calculation method, pressure difference method calculation method, speed density method calculation method.

[0131] Optionally, the device further comprises:

[0132] The processing unit is used to obtain vehicle fault diagnosis information when there is a consistency problem in the first subsystem, and determine the cause of the fault of the first subsystem according to the vehicle fault diagnosis information.

[0133] Since the device 300 is a device corresponding to the method provided in the above method embodiment, the specific implementation of each unit of the device 300 is based on the same concept as the above method embodiment. Therefore, for the specific implementation of each unit of the device 300, reference can be made to the description part of the above method embodiment, which will not be repeated here.

[0134] An embodiment of the present application also provides a device, which includes: a processor, a memory, and a system bus; the processor and the memory are connected via the system bus; the memory is used to store one or more programs, and the one or more programs include instructions, which, when executed by the processor, enable the processor to execute the method described in any one of the above method embodiments.

[0135] An embodiment of the present application provides a computer-readable storage medium, in which instructions are stored. When the instructions are executed on a terminal device, the terminal device executes the method described in any one of the above method embodiments.

[0136] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0137] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

[0138] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for determining the consistency of an engine intake system, characterized in that: The method comprises: In the case of steady-state operation of the engine, a first calculation method is used to calculate a first gas flow rate of a first subsystem in the engine intake system, and a second calculation method is used to calculate a second gas flow rate of the first subsystem, wherein the first calculation method adopts the energy conservation principle, and the accuracy of the second calculation method is affected by the consistency of zero components; determining a deviation between the first gas flow rate and the second gas flow rate; determining consistency of the first subsystem based on the deviation; The energy conservation principle includes: The sum of air energy change, fuel gas energy change, exhaust gas recirculation EGR energy change and heat exchange energy is 0, where: The air energy change is determined based on the air flow rate, the temperature of the mixed gas in the engine intake pipe, the specific heat capacity of the air at the temperature of the mixed gas, the temperature of the air, and the specific heat capacity of the air at the temperature of the air; The gas energy change is determined according to the gas flow rate, the temperature of the mixed gas, the specific heat capacity of the gas at the temperature of the mixed gas, the temperature of the gas, and the specific heat capacity of the gas at the temperature of the gas; The EGR energy change is determined according to the EGR flow rate, the temperature of the mixed gas, the specific heat capacity of the EGR gas at the temperature of the mixed gas, the temperature of the EGR gas, and the specific heat capacity of the EGR gas at the temperature of the EGR gas; The heat exchange energy is determined based on the surface area of ​​the engine intake system, the convective heat transfer coefficient, the convective heat transfer correction coefficient, the temperature of the mixed gas, and the ambient temperature. The heat exchange energy is the energy for heat exchange between the engine intake system and the environment.

2. The method according to claim 1, characterized in that: The first subsystem includes any one of the following: Air subsystem, fuel gas subsystem and exhaust gas recirculation (EGR) subsystem.

3. The method according to claim 1, characterized in that The second calculation method includes any one of the following: Flow meter calculation method, Venturi method calculation method, pressure difference method calculation method, speed density method calculation method.

4. The method according to claim 1, characterized in that The method further comprises: In the case where there is a consistency problem in the first subsystem, vehicle fault diagnosis information is obtained, and a fault cause of the first subsystem is determined according to the vehicle fault diagnosis information.

5. A device for determining the consistency of an engine intake system, characterized in that: The device comprises: a calculation unit, configured to calculate, when the engine is in steady-state operation, a first gas flow rate of a first subsystem in an engine intake system by a first calculation method, and calculate a second gas flow rate of the first subsystem by a second calculation method, wherein the first calculation method adopts the energy conservation principle, and the accuracy of the second calculation method is affected by the consistency of zero components; a first determining unit, configured to determine a deviation between the first gas flow rate and the second gas flow rate; a second determining unit, configured to determine the consistency of the first subsystem according to the deviation; The energy conservation principle includes: The sum of air energy change, fuel gas energy change, exhaust gas recirculation EGR energy change and heat exchange energy is 0, where: The air energy change is determined based on the air flow rate, the temperature of the mixed gas in the engine intake pipe, the specific heat capacity of the air at the temperature of the mixed gas, the temperature of the air, and the specific heat capacity of the air at the temperature of the air; The gas energy change is determined according to the gas flow rate, the temperature of the mixed gas, the specific heat capacity of the gas at the temperature of the mixed gas, the temperature of the gas, and the specific heat capacity of the gas at the temperature of the gas; The EGR energy change is determined according to the EGR flow rate, the temperature of the mixed gas, the specific heat capacity of the EGR gas at the temperature of the mixed gas, the temperature of the EGR gas, and the specific heat capacity of the EGR gas at the temperature of the EGR gas; The heat exchange energy is determined based on the surface area of ​​the engine intake system, the convective heat transfer coefficient, the convective heat transfer correction coefficient, the temperature of the mixed gas, and the ambient temperature. The heat exchange energy is the energy for heat exchange between the engine intake system and the environment.

6. The device according to claim 5, characterized in that The first subsystem includes any one of the following: Air subsystem, fuel gas subsystem and exhaust gas recirculation (EGR) subsystem.

7. A device for determining the consistency of an engine intake system, characterized in that The device includes: a processor, a memory, and a system bus; the processor and the memory are connected via the system bus; the memory is used to store one or more programs, and the one or more programs include instructions, which, when executed by the processor, enable the processor to execute the method described in any one of claims 1 to 4.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions, and when the instructions are executed on a terminal device, the terminal device executes the method according to any one of claims 1 to 4.

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