Engine Fault Detection Method, Controller, and Engine Fault Detection Device

Abstract

The present application provides an engine fault detection method, a controller, and an engine fault detection device. The method includes: when the operating condition of the engine is a first operating condition, obtaining a methane concentration value, where the first operating condition is an operating condition in which the engine operates normally; determining whether the methane concentration value is within a preset concentration range; and when the methane concentration value is within the preset concentration range, determining that the engine has a ventilation fault, where the ventilation fault is a disconnection between the ventilation pipeline and the intake pipeline. This method solves the problem in the prior art that it is extremely easy to have false alarms or misreports of faults when determining the connection status between the ventilation pipeline and the intake pipeline based on the change in gas pressure.

Description

Technical Field

[0001] The present application relates to the technical field of engines, and in particular, to an engine fault detection method, a controller, an engine fault detection device, and a detection system. Background Art

[0002] Currently, the general method for detecting the connection condition of the common end of the intake pipe and the ventilation pipe of the crankcase is to detect the air pressure at the common end of the intake pipe and the ventilation pipe. However, when the change in air pressure is small (for example, the change in air pressure when the intake pipe and the ventilation pipe of the crankcase are normally connected and when the intake pipe and the ventilation pipe of the crankcase are disconnected is small), false alarms or misreports of faults are likely to occur. Summary of the Invention

[0003] The main object of the present application is to provide an engine fault detection method, a controller, an engine fault detection device, and a detection system, so as to at least solve the problem that false alarms or misreports of faults are extremely likely to occur in the prior art when determining the connection condition between the ventilation pipe and the intake pipe according to the change in air pressure.

[0004] To achieve the above object, according to one aspect of the present application, there is provided an engine fault detection method. The engine includes a crankcase, an intake pipe, and a ventilation pipe. The intake port of the crankcase is communicated with one end of the intake pipe, the other end of the intake pipe is communicated with one end of the ventilation pipe, the other end of the ventilation pipe is communicated with the exhaust port of the crankcase, and a methane sensor is installed at the common end of the intake pipe and the ventilation pipe. The methane sensor is used to detect the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe. The methane sensor is communicatively connected to a controller. The engine fault detection method is applied to the controller, and the method includes: when the working condition of the engine is a first working condition, obtaining the methane concentration value, where the first working condition is the working condition when the engine is running normally; determining whether the methane concentration value is within a preset concentration range; when the methane concentration value is within the preset concentration range, determining that the engine has a ventilation fault, where the ventilation fault is that the ventilation pipe is disconnected from the intake pipe.

[0005] Optionally, after obtaining the methane concentration value, the method further includes: determining whether the methane concentration value meets a first preset condition, where the first preset condition is that the methane concentration value is within the preset concentration range and the duration is greater than a first preset time; when the methane concentration value meets the first preset condition, determining that the engine has the ventilation fault and generating a first message, where the first message is a message indicating that the engine has the ventilation fault.

[0006] Optionally, the method further includes: when the operating condition of the engine is the second operating condition, obtaining the methane concentration value, where the second operating condition is the operating condition when the engine is not started; determining whether the methane concentration value meets a second preset condition, where the second preset condition is that the methane concentration value is less than a first preset concentration value and the duration is greater than a second preset time, and the first preset concentration value is less than the lower limit of the preset concentration range; when the methane concentration value is less than the first preset concentration value, generating a second message, where the second message is a message indicating that the methane sensor is credible.

[0007] Optionally, after determining whether the methane concentration value is within the preset concentration range, the method further includes: when the methane concentration value is not within the preset concentration range, determining whether the methane concentration value is greater than a second preset concentration value, where the second preset concentration value is greater than the upper limit of the preset concentration range; when the methane concentration value is greater than the second preset concentration value, generating a third message, where the third message is a message indicating that the engine has a misfire fault.

[0008] Optionally, the engine further includes a front oxygen sensor and a cylinder. The front oxygen sensor is communicatively connected to the controller. The front oxygen sensor is used to determine the air-fuel ratio, where the air-fuel ratio is the ratio of the mass of air entering the cylinder to the mass of fuel entering the cylinder, and the fuel includes methane. After determining whether the methane concentration value is within the preset concentration range, the method further includes: when the methane concentration value is not within the preset concentration range, determining whether the methane concentration value is less than a third preset concentration value, where the third preset concentration value is equal to the lower limit of the preset concentration range; when the methane concentration value is less than the third preset concentration value, obtaining the air-fuel ratio and determining whether the air-fuel ratio is greater than a preset value; when the air-fuel ratio is greater than the preset value, generating a fourth message, where the fourth message is a message indicating that the ventilation fault cannot be detected.

[0009] Optionally, before obtaining the methane concentration value, the method further includes: obtaining the intake air volume of the engine and the fuel injection volume of the engine; when the intake air volume of the engine is within a preset intake air volume range and the fuel injection volume of the engine is within a preset fuel injection volume range, determining that the operating condition of the engine is the first operating condition; when the intake air volume of the engine is less than the preset intake air volume and the fuel injection volume of the engine is less than the preset fuel injection volume, determining that the operating condition of the engine is the second operating condition, where the preset intake air volume is less than the lower limit of the preset intake air volume range, the preset fuel injection volume is less than the lower limit of the preset fuel injection volume range, and the second operating condition is the operating condition when the engine is not started.

[0010] Optionally, before obtaining the methane concentration value, the method further includes: obtaining the engine speed and the engine torque; when the engine speed is within a preset speed range and the engine torque is within a preset torque range, determining that the engine condition is the first condition; when the engine speed is less than the preset speed and the engine torque is less than the preset torque, determining that the engine condition is the second condition, where the preset speed is less than the lower limit of the preset speed range, the preset torque is less than the lower limit of the preset torque range, and the second condition is the condition that the engine is not started.

[0011] According to another aspect of the present application, a controller is provided. The controller is communicatively connected to a methane sensor. The methane sensor is installed at the common end of the intake pipe and the ventilation pipe. The methane sensor is used to detect the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe. The controller includes: a first obtaining unit, configured to obtain the methane concentration value when the engine condition is the first condition, where the first condition is the condition that the engine is running normally; a first determining unit, configured to determine whether the methane concentration value is within a second preset concentration range; a second determining unit, configured to determine that the engine has a ventilation failure when the methane concentration value is within the second preset concentration range, where the ventilation failure is that the ventilation pipe is disconnected from the intake pipe.

[0012] According to yet another aspect of the present application, an engine fault detection device is provided. The engine fault detection device includes: a controller, where the controller is configured to execute any one of the engine fault detection methods; an engine, where the engine includes a crankcase, an intake pipe, a ventilation pipe, and a front oxygen sensor. The intake port of the crankcase is communicated with one end of the intake pipe, the other end of the intake pipe is communicated with one end of the ventilation pipe, the other end of the ventilation pipe is communicated with the exhaust port of the crankcase, the front oxygen sensor is communicatively connected to the controller, and the front oxygen sensor is used to determine the air-fuel ratio; a methane sensor, where the methane sensor is installed at the common end of the intake pipe and the ventilation pipe, the methane sensor is used to detect the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe, and the methane sensor is communicatively connected to the controller.

[0013] According to still another aspect of the present application, a detection system is provided. The detection system includes the device and a client, and the controller is communicatively connected to the client.

[0014] Applying the technical solution of the present application, when the engine is running normally, if the intake pipe and the ventilation pipe are well connected, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should be maintained within a certain concentration range. If it is determined that the intake pipe and the ventilation pipe are disconnected, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should decrease significantly. When the controller determines that the methane concentration value detected by the methane sensor on the inner wall of the common end of the intake pipe and the ventilation pipe is within the preset concentration range, that is, when it is determined that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe has decreased significantly, it can be determined that the intake pipe and the ventilation pipe are disconnected, solving the problem of easy malfunction false alarms or misreports in determining the connection status of the ventilation pipe and the intake pipe according to the air pressure change in the prior art. Brief Description of the Drawings

[0015] The accompanying drawings forming a part of this application are used to provide a further understanding of this application. The schematic embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation of this application. In the drawings:

[0016] Figure 1 Shows a schematic flow chart of a method for detecting engine faults provided by an embodiment of this application;

[0017] Figure 2 Shows a schematic diagram of the installation position of a methane sensor provided by an embodiment of this application;

[0018] Figure 3 Shows a schematic flow chart of another method for detecting engine faults provided by an embodiment of this application;

[0019] Figure 4 Shows a schematic flow chart of yet another method for detecting engine faults provided by an embodiment of this application;

[0020] Figure 5 Shows a schematic flow chart of still another method for detecting engine faults provided by an embodiment of this application;

[0021] Figure 6 Shows a structural block diagram of a controller provided by an embodiment of this application.

[0022] Among them, the above-mentioned drawings include the following reference numerals:

[0023] 10, crankcase; 20, intake pipe; 30, ventilation pipe; 40, methane sensor. Detailed Description of the Embodiment

[0024] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The following will refer to the drawings and combine the embodiments to detail this application.

[0025] In order to enable those skilled in the art to better understand the solution of this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of this application.

[0026] It should be noted that the terms "first", "second", etc. in the specification and claims of this application and the above-mentioned accompanying drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so as to implement the embodiments of this application described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0027] As introduced in the background art, in the prior art, it is extremely easy to have problems of false alarms or misreports of failures when determining the connection status of the ventilation pipeline and the intake pipeline according to the air pressure change. To solve the problem that it is extremely easy to have false alarms or misreports of failures when determining the connection status of the ventilation pipeline and the intake pipeline according to the air pressure change in the prior art, the embodiments of this application provide an engine fault detection method, a controller, an engine fault detection device, and a detection system.

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0029] In this embodiment, an engine fault detection method is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0030] The engine includes a crankcase, an intake pipe and a ventilation pipe. The intake port of the crankcase communicates with one end of the intake pipe, the other end of the intake pipe communicates with one end of the ventilation pipe, the other end of the ventilation pipe communicates with the exhaust port of the crankcase, a methane sensor is installed at the common end of the intake pipe and the ventilation pipe, the methane sensor is used to detect the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe, the methane sensor is communicatively connected to a controller, and the engine fault detection method uses the controller.

[0031] Figure 1 is a flowchart of the engine fault detection method according to an embodiment of the present application. As Figure 1 shown, the method includes the following steps:

[0032] Step S101, when the operating condition of the engine is the first operating condition, obtain the methane concentration value, where the first operating condition is the operating condition when the engine is running normally;

[0033] Specifically, when the engine is running normally, a certain amount of unburned methane in the leakage of the piston of the cylinder of the engine enters the crankcase, then enters the intake pipe through the ventilation pipe, and returns to the cylinder of the engine for combustion. That is, when the engine is running normally, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe is within the normal concentration range (the normal concentration range is the concentration value range where the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe is located when the intake pipe and the ventilation pipe are well connected, and the lower limit value of the normal concentration range is equal to the upper limit value of the preset concentration range). When the engine is running normally, the controller continuously obtains the methane concentration value detected by the methane sensor on the inner wall of the common end of the intake pipe and the ventilation pipe.

[0034] It should be noted that, as Figure 2 shown, the intake port of the crankcase 10 communicates with one end of the intake pipe 20, the other end of the intake pipe 20 communicates with one end of the ventilation pipe 30, the other end of the ventilation pipe 30 communicates with the exhaust port of the crankcase 10, a methane sensor 40 is installed at the common end of the intake pipe 20 and the ventilation pipe 30, and the methane sensor 40 is used to detect the methane concentration value on the inner wall of the common end of the intake pipe 20 and the ventilation pipe 30.

[0035] Step S102, determine whether the methane concentration value is within the preset concentration range;

[0036] Specifically, when the engine is running normally, if the intake pipe and the ventilation pipe are connected properly, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should be within the normal concentration range. If it is determined that the intake pipe and the ventilation pipe are disconnected, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should be reduced below the lower limit of the normal concentration range. The controller determines whether the methane concentration value detected by the methane sensor on the inner wall of the common end of the intake pipe and the ventilation pipe is within the preset concentration range, that is, determines whether the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe is reduced below the lower limit of the normal concentration range, so as to determine whether the intake pipe and the ventilation pipe are disconnected.

[0037] Step S103, when the methane concentration value is within the preset concentration range, it is determined that the engine has a ventilation fault, and the ventilation fault is that the ventilation pipe and the intake pipe are disconnected.

[0038] Specifically, the controller determines that the methane concentration value detected by the methane sensor on the inner wall of the common end of the intake pipe and the ventilation pipe is within the preset concentration range, that is, determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe is reduced below the lower limit of the normal concentration range, and determines that the intake pipe and the ventilation pipe are disconnected.

[0039] In order to improve the accuracy of ventilation fault detection, in an alternative solution, after the above step S201, the method further includes:

[0040] Determine whether the methane concentration value meets a first preset condition, where the first preset condition is that the methane concentration value is within the preset concentration range and the duration is greater than a first preset time;

[0041] When the methane concentration value meets the first preset condition, it is determined that the engine has the ventilation fault, and a first message is generated, where the first message is a message indicating that the engine has the ventilation fault.

[0042] In this embodiment, the controller determines that the methane concentration value detected by the methane sensor on the inner wall of the common end of the intake pipe and the ventilation pipe is within the preset concentration range and the duration is greater than the first preset time, that is, determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe is reduced below the lower limit of the normal concentration range and lasts for a certain time, and determines that the intake pipe and the ventilation pipe are disconnected to avoid contingency and improve the accuracy of ventilation fault detection.

[0043] In order to ensure the accuracy of the methane sensor, in an alternative solution, as Figure 3 shown, the method further includes:

[0044] Step S201, when the operating condition of the above engine is the second operating condition, obtain the above methane concentration value, where the second operating condition is the operating condition when the above engine is not started;

[0045] Specifically, when the engine is not started, no methane enters the crankcase. That is, when the engine is not started, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should be 0. When the engine is not started, the controller continuously obtains the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor.

[0046] Step S202, determine whether the above methane concentration value meets the second preset condition. The second preset condition is that the methane concentration value is less than the first preset concentration value and the duration is greater than the second preset time. The first preset concentration value is less than the lower limit of the above preset concentration range;

[0047] Specifically, when the engine is not started, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should be 0. The controller determines whether the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is less than the first preset concentration value (the first preset concentration value is close to 0) to determine the accuracy of the methane sensor.

[0048] Step S203, when the above methane concentration value is less than the first preset concentration value, generate a second message, where the second message is a message indicating that the above methane sensor is credible.

[0049] Specifically, the controller determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is less than the first preset concentration value. At this time, it is determined that the data detected by the methane sensor is accurate.

[0050] In this embodiment, when the engine is not started, the controller determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is less than the first preset concentration value. At this time, it is determined that the data detected by the methane sensor is accurate. When the controller determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is greater than or equal to the first preset concentration value, at this time, it is determined that the data detected by the methane sensor is inaccurate, and the above message indicating that the methane sensor is not credible is generated, thereby achieving the purpose of detecting the accuracy of the methane sensor.

[0051] In order to detect the engine misfire fault, in an alternative solution, after the above step S202, the method further includes:

[0052] When the methane concentration value is not within the preset concentration range, determine whether the methane concentration value is greater than a second preset concentration value, where the second preset concentration value is greater than the upper limit of the preset concentration range;

[0053] When the methane concentration value is greater than the second preset concentration value, generate a third message, where the third message is a message indicating that a misfire fault has occurred in the engine.

[0054] In this embodiment, when the controller determines that the methane concentration value detected by the methane sensor at the inner wall of the common end of the intake pipe and the ventilation pipe is greater than the second preset concentration value, it can be determined that the engine combustion is incomplete, there is a large amount of unburned methane, and a misfire fault has occurred, thereby realizing the detection of the engine misfire fault.

[0055] It should be noted that the above engine further includes a front oxygen sensor and a cylinder. The front oxygen sensor is communicatively connected to the controller. The front oxygen sensor is used to determine the air-fuel ratio, where the air-fuel ratio is the ratio of the mass of air entering the cylinder to the mass of fuel entering the cylinder, and the fuel includes methane.

[0056] In order to detect an air-fuel ratio control fault, in an alternative solution, after the step S202, the method further includes:

[0057] When the methane concentration value is not within the preset concentration range, determine whether the methane concentration value is less than a third preset concentration value, where the third preset concentration value is equal to the lower limit of the preset concentration range;

[0058] When the methane concentration value is less than the third preset concentration value, obtain the air-fuel ratio and determine whether the air-fuel ratio is greater than a preset value;

[0059] When the air-fuel ratio is greater than the preset value, generate a fourth message, where the fourth message is a message indicating that the ventilation fault cannot be detected.

[0060] In this embodiment, when the controller determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is less than the third preset concentration value, it is then determined whether the air-fuel ratio is greater than the preset value, that is, it is determined whether the fact that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe is less than the third preset concentration value is caused by a malfunction of the air-fuel ratio control system. When the air-fuel ratio is greater than the preset value, it can be determined that there is a malfunction in the engine's air-fuel ratio control system (the air-fuel ratio control system should adjust the air-fuel ratio to the preset value, but due to a malfunction in the air-fuel ratio control system, at this time, the air-fuel ratio is greater than the preset value, which will cause the methane concentration to decrease), that is, it is determined that the fact that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe is less than the third preset concentration value is caused by a malfunction of the air-fuel ratio control system, thereby realizing the detection of air-fuel ratio control faults.

[0061] In order to determine that the engine is fault-free, in an alternative solution, after the above step S202, the method further includes:

[0062] When the methane concentration value is not within the preset concentration range, it is determined whether the methane concentration value is within the normal concentration range. The lower limit value of the normal concentration range is equal to the upper limit value of the preset concentration range, and the upper limit value of the normal concentration range is equal to the second preset concentration value;

[0063] When the methane concentration value is within the normal concentration range, it is determined that the engine is fault-free and a fifth message is generated. The fifth message is a message indicating that the engine is fault-free.

[0064] In this embodiment, when the engine is running normally, if the connection between the intake pipe and the ventilation pipe is intact, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should be within the normal concentration range. When the controller determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is within the normal concentration range, it can be determined that the connection between the intake pipe and the ventilation pipe is intact.

[0065] In order to determine the operating condition of the engine, in an alternative solution, after the above step S201, the method further includes:

[0066] Obtain the intake air volume of the engine and the fuel injection volume of the engine;

[0067] When the intake air volume of the above engine is within the preset intake air volume range and the fuel injection volume of the above engine is within the preset fuel injection volume range, it is determined that the working condition of the above engine is the above first working condition. When the intake air volume of the above engine is less than the preset intake air volume and the above fuel injection volume of the above engine is less than the preset fuel injection volume, it is determined that the working condition of the above engine is the second working condition. The above preset intake air volume is less than the lower limit value of the above preset intake air volume range, and the above preset fuel injection volume is less than the lower limit value of the above preset fuel injection volume range. The above second working condition is the working condition where the above engine is not started.

[0068] In this embodiment, the working condition of the engine can be determined according to the intake air volume and fuel injection volume of the engine. When the intake air volume of the engine is within the preset intake air volume range (for example, greater than 40% of the maximum intake air volume of the engine) and the fuel injection volume of the engine is within the preset fuel injection volume range (for example, 40% of the maximum fuel injection volume), it is determined that the engine is working normally. When the intake air volume of the engine is less than the preset intake air volume (the preset intake air volume is close to 0) and the fuel injection volume of the engine is less than the preset fuel injection volume (the preset fuel injection volume is close to 0), it is determined that the engine is not started.

[0069] In order to determine the working condition of the engine, in an alternative solution, after the above step S201, the method further includes:

[0070] Obtain the rotational speed of the above engine and the torque of the above engine;

[0071] When the rotational speed of the above engine is within the preset rotational speed range and the torque of the above engine is within the preset torque range, it is determined that the working condition of the above engine is the above first working condition. When the rotational speed of the above engine is less than the preset rotational speed and the above torque of the above engine is less than the preset torque, it is determined that the working condition of the above engine is the second working condition. The above preset rotational speed is less than the lower limit value of the above preset rotational speed range, and the above preset torque is less than the lower limit value of the above preset torque range. The above second working condition is the working condition where the above engine is not started.

[0072] In this embodiment, the working condition of the engine can be determined according to the rotational speed and torque of the engine. When the rotational speed of the engine is within the preset rotational speed range (for example, within 1000 rpm - 1600 rpm) and the torque of the engine is within the preset torque range (for example, 40% of the maximum torque), it is determined that the engine is working normally. When the rotational speed of the engine is less than the preset rotational speed (the preset rotational speed is close to 0) and the torque of the engine is less than the preset torque (the preset torque is close to 0), it is determined that the engine is not started.

[0073] Through the above embodiments, when the engine is running normally, if the intake pipeline and the ventilation pipeline are well connected, the methane concentration value on the inner wall of the common end of the intake pipeline and the ventilation pipeline should be maintained within a certain concentration range. If it is determined that the intake pipeline and the ventilation pipeline are disconnected, the methane concentration value on the inner wall of the common end of the intake pipeline and the ventilation pipeline should decrease significantly. When the controller determines that the methane concentration value detected by the methane sensor on the inner wall of the common end of the intake pipeline and the ventilation pipeline is within the preset concentration range, that is, when it is determined that the methane concentration value on the inner wall of the common end of the intake pipeline and the ventilation pipeline has decreased significantly, it can be determined that the intake pipeline and the ventilation pipeline are disconnected, solving the problem that it is extremely easy to have false alarms or misreports of faults when determining the connection status of the ventilation pipeline and the intake pipeline according to the air pressure change.

[0074] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the implementation process of the engine fault detection method of the present application will be described in detail below in conjunction with specific embodiments.

[0075] This embodiment relates to a specific engine fault detection method, as Figure 4 shown, including the following steps:

[0076] Step S11: Determine the working condition of the engine according to the intake air volume and fuel injection volume of the engine;

[0077] Step S12: When the engine is in the second working condition (the intake air volume of the engine is less than the preset intake air volume and the fuel injection volume of the engine is less than the preset fuel injection volume), check the accuracy of the methane sensor, that is, determine whether the methane concentration value detected by the methane sensor is less than the first preset concentration value (the first preset concentration value is close to 0) to determine whether the methane sensor is reliable. When the methane concentration value detected by the methane sensor is less than the first preset concentration value, it is determined that the methane sensor is reliable; otherwise, it is determined that the methane sensor is unreliable;

[0078] Step S13: When the engine is in the first working condition, obtain the methane concentration value and determine whether the methane concentration value detected by the methane sensor is within the preset concentration range to determine whether the engine has a ventilation fault;

[0079] Step S14: When it is determined that the methane concentration value detected by the methane sensor is within the preset concentration range, it is determined that the engine has a ventilation fault (the intake pipeline and the ventilation pipeline are disconnected);

[0080] Step S15: When it is determined that the methane concentration value detected by the methane sensor is not within the preset concentration range, determine whether the methane concentration value detected by the methane sensor is greater than the second preset concentration value;

[0081] Step S16: When it is determined that the methane concentration value detected by the methane sensor is greater than the second preset concentration value, it is determined that the engine has a misfire fault; otherwise, it is determined whether the methane concentration value detected by the methane sensor is less than the third preset concentration value.

[0082] Step S17: When it is determined that the methane concentration value detected by the methane sensor is less than the third preset concentration value (the above-mentioned third preset concentration value is equal to the lower limit value of the above-mentioned preset concentration range), it is determined that the engine has an air-fuel ratio control fault; otherwise, it is determined whether the methane concentration value detected by the methane sensor is within the normal concentration range.

[0083] Step S18: When it is determined that the methane concentration value detected by the methane sensor is within the normal concentration range (the lower limit value of the above-mentioned normal concentration range is equal to the upper limit value of the above-mentioned preset concentration range, and the upper limit value of the above-mentioned normal concentration range is equal to the above-mentioned second preset concentration value), it is determined that the connection between the intake pipe and the ventilation pipe is intact.

[0084] This embodiment relates to another specific engine fault detection method. As Figure 5 shown, it includes the following steps:

[0085] Step S21: Determine the operating condition of the engine according to the engine speed and torque.

[0086] Step S22: When the engine is in the second operating condition (the engine speed is less than the preset speed and the engine torque is less than the preset torque), check the accuracy of the methane sensor, that is, determine whether the methane concentration value detected by the methane sensor is less than the first preset concentration value (the first preset concentration value is close to 0) to determine whether the methane sensor is reliable. When the methane concentration value detected by the methane sensor is less than the first preset concentration value, it is determined that the methane sensor is reliable; otherwise, it is determined that the methane sensor is unreliable.

[0087] Step S23: When the engine is in the first operating condition, obtain the methane concentration value and determine whether the methane concentration value detected by the methane sensor is within the preset concentration range to determine whether the engine has a ventilation fault.

[0088] Step S24: When it is determined that the methane concentration value detected by the methane sensor is within the preset concentration range, it is determined that the engine has a ventilation fault (the intake pipe and the ventilation pipe are disconnected).

[0089] Step S25: When it is determined that the methane concentration value detected by the methane sensor is not within the preset concentration range, it is determined whether the methane concentration value detected by the methane sensor is greater than the second preset concentration value.

[0090] Step S26: When it is determined that the methane concentration value detected by the methane sensor is greater than the second preset concentration value, it is determined that the engine has a misfire fault; otherwise, it is determined whether the methane concentration value detected by the methane sensor is less than the third preset concentration value.

[0091] Step S27: When it is determined that the methane concentration value detected by the methane sensor is less than the third preset concentration value (the above-mentioned third preset concentration value is equal to the lower limit value of the above-mentioned preset concentration range), it is determined that the engine has an air-fuel ratio control fault; otherwise, it is determined whether the methane concentration value detected by the methane sensor is within the normal concentration range.

[0092] Step S28: When it is determined that the methane concentration value detected by the methane sensor is within the normal concentration range (the lower limit value of the above-mentioned normal concentration range is equal to the upper limit value of the above-mentioned preset concentration range, and the upper limit value of the above-mentioned normal concentration range is equal to the above-mentioned second preset concentration value), it is determined that the connection between the intake pipe and the ventilation pipe is intact.

[0093] It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. And although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0094] The controller provided by the embodiments of the present application will be introduced below.

[0095] Figure 6 It is a schematic diagram of the controller according to the embodiments of the present application. As Figure 6 shown, the controller includes:

[0096] A first acquisition unit 300, configured to acquire the methane concentration value when the operating condition of the engine is the first operating condition, and the first operating condition is the operating condition when the engine is operating normally.

[0097] Specifically, when the engine is operating normally, there is a certain amount of unburned methane in the leakage of the piston of the engine cylinder entering the crankcase, and then entering the intake pipe through the ventilation pipe and returning to the engine cylinder for combustion. That is, when the engine is operating normally, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe is within the normal concentration range (the normal concentration range is the concentration value range where the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe is located when the connection between the intake pipe and the ventilation pipe is intact, and the lower limit value of the normal concentration range is equal to the upper limit value of the preset concentration range). When the engine is operating normally, the controller continuously acquires the methane concentration value detected by the methane sensor on the inner wall of the common end of the intake pipe and the ventilation pipe.

[0098] It should be noted that as Figure 2As shown, the intake port of the above-mentioned crankcase 10 is communicated with one end of the above-mentioned intake pipe 20, the other end of the above-mentioned intake pipe 20 is communicated with one end of the above-mentioned ventilation pipe 30, the other end of the above-mentioned ventilation pipe 30 is communicated with the outlet port of the above-mentioned crankcase 10, a methane sensor 40 is installed at the common end of the above-mentioned intake pipe 20 and the above-mentioned ventilation pipe 30, and the above-mentioned methane sensor 40 is used to detect the methane concentration value on the inner wall of the common end of the above-mentioned intake pipe 20 and the above-mentioned ventilation pipe 30.

[0099] A first determination unit 400, configured to determine whether the above-mentioned methane concentration value is within a preset concentration range;

[0100] Specifically, when the engine is running normally, if the connection between the intake pipe and the ventilation pipe is intact, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should be within the normal concentration range. If it is determined that the intake pipe and the ventilation pipe are disconnected, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should be reduced below the lower limit value of the normal concentration range. The controller determines whether the methane concentration value detected by the methane sensor on the inner wall of the common end of the intake pipe and the ventilation pipe is within the preset concentration range, that is, determines whether the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe is reduced below the lower limit value of the normal concentration range, so as to determine whether the intake pipe and the ventilation pipe are disconnected.

[0101] A second determination unit 500, when the above-mentioned methane concentration value is within the above-mentioned preset concentration range, determines that the above-mentioned engine has a ventilation failure, and the above-mentioned ventilation failure is that the above-mentioned ventilation pipe is disconnected from the above-mentioned intake pipe.

[0102] Specifically, the controller determines that the methane concentration value detected by the methane sensor on the inner wall of the common end of the intake pipe and the ventilation pipe is within the preset concentration range, that is, determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe is reduced below the lower limit value of the normal concentration range, and determines that the intake pipe and the ventilation pipe are disconnected.

[0103] In order to improve the accuracy of ventilation failure detection, in an alternative solution, the above-mentioned controller further includes:

[0104] A third determination unit, configured to determine whether the above-mentioned methane concentration value meets a first preset condition, and the above-mentioned first preset condition is that the above-mentioned methane concentration value is within the above-mentioned preset concentration range and the duration is greater than a first preset time;

[0105] A fourth determination unit, when the above-mentioned methane concentration value meets the above-mentioned first preset condition, determines that the above-mentioned engine has the above-mentioned ventilation failure and generates a first message, and the above-mentioned first message is a message indicating that the above-mentioned engine has the above-mentioned ventilation failure.

[0106] In this embodiment, the controller determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is within the preset concentration range and the duration is greater than the first preset time, that is, it is determined that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe has dropped below the lower limit of the normal concentration range and lasted for a certain time, and it is determined that the connection between the air pipe and the ventilation pipe is disconnected to avoid contingency and improve the accuracy of ventilation fault detection.

[0107] To ensure the accuracy of the methane sensor, the above-mentioned controller further includes:

[0108] A third acquisition unit, configured to acquire the methane concentration value when the operating condition of the above-mentioned engine is the second operating condition, and the second operating condition is the operating condition when the above-mentioned engine is not started;

[0109] Specifically, when the engine is not started, no methane enters the crankcase. That is, when the engine is not started, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should be 0. When the engine is not started, the controller continuously acquires the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor.

[0110] A fifth determination unit, configured to determine whether the methane concentration value satisfies a second preset condition, and the second preset condition is that the methane concentration value is less than the first preset concentration value and the duration is greater than the second preset time, and the first preset concentration value is less than the lower limit of the preset concentration range;

[0111] Specifically, when the engine is not started, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should be 0. The controller determines whether the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is less than the first preset concentration value (the first preset concentration value is close to 0) to determine the accuracy of the methane sensor.

[0112] A first generation unit, configured to generate a second message when the methane concentration value is less than the first preset concentration value, and the second message is a message indicating that the methane sensor is credible.

[0113] Specifically, the controller determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is less than the first preset concentration value. At this time, it is determined that the data detected by the methane sensor is accurate.

[0114] In this embodiment, when the engine is not started, the controller determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is less than the first preset concentration value. At this time, it is determined that the data detected by the methane sensor is accurate. When the controller determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is greater than or equal to the first preset concentration value, it is determined at this time that the data detected by the methane sensor is inaccurate, and the above-mentioned message that the methane sensor is not credible is generated, thereby achieving the purpose of detecting the accuracy of the methane sensor.

[0115] In order to detect the engine misfire fault, in an alternative solution, the above-mentioned controller further includes:

[0116] A sixth determination unit, configured to determine whether the methane concentration value is greater than a second preset concentration value when the methane concentration value is not within the preset concentration range, and the second preset concentration value is greater than the upper limit value of the preset concentration range;

[0117] A third generation unit, configured to generate a third message when the methane concentration value is greater than the second preset concentration value, and the third message is a message indicating that the engine has a misfire fault.

[0118] In this embodiment, when the controller determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is greater than the second preset concentration value, it can be determined that the engine combustion is incomplete, there is a large amount of unburned methane, and a misfire fault occurs, thereby realizing the detection of the engine misfire fault.

[0119] It should be noted that the above-mentioned engine further includes a front oxygen sensor and a cylinder. The front oxygen sensor is communicatively connected to the controller. The front oxygen sensor is used to determine the air-fuel ratio, and the air-fuel ratio is the ratio of the mass of air entering the cylinder to the mass of fuel entering the cylinder, and the fuel includes methane.

[0120] In order to detect the air-fuel ratio control fault, in an alternative solution, the above-mentioned controller further includes:

[0121] A seventh determination unit, configured to determine whether the methane concentration value is less than a third preset concentration value when the methane concentration value is not within the preset concentration range, and the third preset concentration value is less than the lower limit value of the preset concentration range;

[0122] A fourth acquisition unit, configured to acquire the air-fuel ratio and determine whether the air-fuel ratio is greater than a preset value when the methane concentration value is less than the third preset concentration value;

[0123] A third generation unit, configured to generate a fourth message when the air-fuel ratio is greater than the preset value, where the fourth message is a message indicating that the ventilation fault cannot be detected.

[0124] In this embodiment, the controller determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is less than a third preset concentration value. At this time, it is determined whether the air-fuel ratio is greater than the preset value, that is, it is determined whether the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe being less than the third preset concentration value is caused by a fault in the air-fuel ratio control system. When the air-fuel ratio is greater than the preset value, it can be determined that there is a fault in the air-fuel ratio control system of the engine (the air-fuel ratio control system should adjust the air-fuel ratio to the preset value, but due to a fault in the air-fuel ratio control system, at this time, the air-fuel ratio is greater than the preset value, which will cause the methane concentration to decrease), that is, it is determined that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe being less than the third preset concentration value is caused by a fault in the air-fuel ratio control system, thereby realizing the detection of the air-fuel ratio control fault.

[0125] In order to determine that the engine is fault-free, in an alternative solution, the controller further includes:

[0126] An eighth determination unit, configured to determine whether the methane concentration value is within the normal concentration range when the methane concentration value is not within the preset concentration range;

[0127] A ninth determination unit, configured to determine that the engine is fault-free and generate a fifth message when the methane concentration value is within the normal concentration range, where the fifth message is a message indicating that the engine is fault-free.

[0128] In this embodiment, when the engine is running normally, if the connection between the intake pipe and the ventilation pipe is intact, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should be within the normal concentration range. When the controller determines that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe detected by the methane sensor is within the normal concentration range, it can be determined that the connection between the intake pipe and the ventilation pipe is intact.

[0129] In order to determine the operating condition of the engine, in an alternative solution, the controller further includes:

[0130] A fifth acquisition unit, configured to acquire the intake air volume of the engine and the fuel injection volume of the engine;

[0131] A tenth determination unit is configured to determine that the operating condition of the engine is the first operating condition when the intake air volume of the engine is within a preset intake air volume range and the fuel injection volume of the engine is within a preset fuel injection volume range, and to determine that the operating condition of the engine is the second operating condition when the intake air volume of the engine is less than the preset intake air volume and the fuel injection volume of the engine is less than the preset fuel injection volume. The preset intake air volume is less than the lower limit value of the preset intake air volume range, the preset fuel injection volume is less than the lower limit value of the preset fuel injection volume range, and the second operating condition is the operating condition when the engine is not started.

[0132] In this embodiment, the operating condition of the engine can be determined according to the intake air volume and the fuel injection volume of the engine. When the intake air volume of the engine is within a preset intake air volume range (for example, greater than 40% of the maximum intake air volume of the engine) and the fuel injection volume of the engine is within a preset fuel injection volume range (for example, 40% of the maximum fuel injection volume), it is determined that the engine is operating normally. When the intake air volume of the engine is less than the preset intake air volume (the preset intake air volume is close to 0) and the fuel injection volume of the engine is less than the preset fuel injection volume (the preset fuel injection volume is close to 0), it is determined that the engine is not started.

[0133] In an alternative solution for determining the operating condition of the engine, the controller further includes:

[0134] A sixth acquisition unit is configured to acquire the rotational speed of the engine and the torque of the engine;

[0135] An eleventh determination unit is configured to determine that the operating condition of the engine is the first operating condition when the rotational speed of the engine is within a preset rotational speed range and the torque of the engine is within a preset torque range, and to determine that the operating condition of the engine is the second operating condition when the rotational speed of the engine is less than the preset rotational speed and the torque of the engine is less than the preset torque. The preset rotational speed is less than the lower limit value of the preset rotational speed range, the preset torque is less than the lower limit value of the preset torque range, and the second operating condition is the operating condition when the engine is not started.

[0136] In this embodiment, the operating condition of the engine can be determined according to the rotational speed and the torque of the engine. When the rotational speed of the engine is within a preset rotational speed range (for example, within 1000 rpm - 1600 rpm) and the torque of the engine is within a preset torque range (for example, 40% of the maximum torque), it is determined that the engine is operating normally. When the rotational speed of the engine is less than the preset rotational speed (the preset rotational speed is close to 0) and the torque of the engine is less than the preset torque (the preset torque is close to 0), it is determined that the engine is not started.

[0137] Through the above embodiments, when the engine is running normally, if the intake pipe and the ventilation pipe are well connected, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should be maintained within a certain concentration range. If it is determined that the intake pipe and the ventilation pipe are disconnected, the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe should decrease significantly. When the controller determines that the methane concentration value detected by the methane sensor on the inner wall of the common end of the intake pipe and the ventilation pipe is within the preset concentration range, that is, when it is determined that the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe has decreased significantly, it can be determined that the intake pipe and the ventilation pipe are disconnected, solving the problem in the prior art that it is extremely easy to have false alarms or misreports of faults when determining the connection status of the ventilation pipe and the intake pipe according to the air pressure change.

[0138] The above controller includes a processor and a memory. The above first acquisition unit, first determination unit, second determination unit, etc. are all stored in the memory as program units, and the processor executes the above program units stored in the memory to implement corresponding functions. The above modules are all located in the same processor; or, the above modules are respectively located in different processors in any combination form.

[0139] The processor contains a kernel, and the kernel retrieves the corresponding program unit from the memory. One or more kernels can be set, and by adjusting the kernel parameters, the problem in the prior art that it is extremely easy to have false alarms or misreports of faults when determining the connection status of the ventilation pipe and the intake pipe according to the air pressure change is solved.

[0140] The memory may include non-permanent memory in a computer-readable medium, forms such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash memory (flash RAM), and the memory includes at least one storage chip.

[0141] An embodiment of the present invention provides an engine fault detection device. The above engine fault detection device includes: a controller, the controller is used to execute any one of the above engine fault detection methods; an engine, the engine includes a crankcase, an intake pipe, a ventilation pipe, and a front oxygen sensor. The intake port of the crankcase is communicated with one end of the intake pipe, the other end of the intake pipe is communicated with one end of the ventilation pipe, the other end of the ventilation pipe is communicated with the exhaust port of the crankcase, the front oxygen sensor is communicatively connected with the controller, and the front oxygen sensor is used to determine the air-fuel ratio; a methane sensor, the methane sensor is installed at the common end of the intake pipe and the ventilation pipe, the methane sensor is used to detect the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe, and the methane sensor is communicatively connected with the controller.

[0142] An embodiment of the present invention provides a detection system. The detection system includes the above-mentioned device and a client, and the controller communicates with the client.

[0143] The present application also provides a computer program product, which, when executed on a data processing device, is adapted to execute a program initialized with at least the following method steps:

[0144] An engine fault detection method, where the engine includes a crankcase, an intake pipeline, and a ventilation pipeline. The intake port of the crankcase is communicated with one end of the intake pipeline, the other end of the intake pipeline is communicated with one end of the ventilation pipeline, the other end of the ventilation pipeline is communicated with the outlet port of the crankcase, a methane sensor is installed at the common end of the intake pipeline and the ventilation pipeline, the methane sensor is used to detect the methane concentration value on the inner wall of the common end of the intake pipeline and the ventilation pipeline, the methane sensor is communicatively connected to a controller, and the engine fault detection method applies the controller. The method includes: when the working condition of the engine is the first working condition, obtaining the methane concentration value, where the first working condition is the working condition when the engine is running normally; determining whether the methane concentration value is within a preset concentration range; when the methane concentration value is within the preset concentration range, determining that the engine has a ventilation fault, where the ventilation fault is a disconnection between the ventilation pipeline and the intake pipeline.

[0145] Optionally, after obtaining the methane concentration value, the method further includes: determining whether the methane concentration value meets a first preset condition, where the first preset condition is that the methane concentration value is within the preset concentration range and the duration is greater than a first preset time; when the methane concentration value meets the first preset condition, determining that the engine has the ventilation fault and generating a first message, where the first message is a message indicating that the engine has the ventilation fault.

[0146] Optionally, the method further includes: when the working condition of the engine is the second working condition, obtaining the methane concentration value, where the second working condition is the working condition when the engine is not started; determining whether the methane concentration value meets a second preset condition, where the second preset condition is that the methane concentration value is less than a first preset concentration value and the duration is greater than a second preset time, and the first preset concentration value is less than the lower limit of the preset concentration range; when the methane concentration value is less than the first preset concentration value, generating a second message, where the second message is a message indicating that the methane sensor is reliable.

[0147] Optionally, after determining whether the above methane concentration value is within a preset concentration range, the above method further includes: when the methane concentration value is not within the preset concentration range, determining whether the methane concentration value is greater than a second preset concentration value, where the second preset concentration value is greater than the upper limit value of the preset concentration range; when the methane concentration value is greater than the second preset concentration value, generating a third message, where the third message is a message indicating that a misfire fault has occurred in the engine.

[0148] Optionally, the above engine further includes a front oxygen sensor and a cylinder. The front oxygen sensor is communicatively connected to the controller. The front oxygen sensor is used to determine the air-fuel ratio, where the air-fuel ratio is the ratio of the mass of air entering the cylinder to the mass of fuel entering the cylinder, and the fuel includes methane. After determining whether the above methane concentration value is within a preset concentration range, the above method further includes: when the methane concentration value is not within the preset concentration range, determining whether the methane concentration value is less than a third preset concentration value, where the third preset concentration value is equal to the lower limit value of the preset concentration range; when the methane concentration value is less than the third preset concentration value, obtaining the air-fuel ratio and determining whether the air-fuel ratio is greater than a preset value; when the air-fuel ratio is greater than the preset value, generating a fourth message, where the fourth message is a message indicating that the ventilation fault cannot be detected.

[0149] Optionally, before obtaining the above methane concentration value, the above method further includes: obtaining the intake air volume of the above engine and the fuel injection volume of the above engine; when the intake air volume of the above engine is within a preset intake air volume range and the fuel injection volume of the above engine is within a preset fuel injection volume range, determining that the operating condition of the above engine is the above first operating condition; when the intake air volume of the above engine is less than the preset intake air volume and the fuel injection volume of the above engine is less than the preset fuel injection volume, determining that the operating condition of the above engine is the second operating condition, where the preset intake air volume is less than the lower limit value of the preset intake air volume range, the preset fuel injection volume is less than the lower limit value of the preset fuel injection volume range, and the second operating condition is the operating condition where the above engine is not started.

[0150] Optionally, before obtaining the above methane concentration value, the above method further includes: obtaining the rotational speed of the above engine and the torque of the above engine; when the rotational speed of the above engine is within a preset rotational speed range and the torque of the above engine is within a preset torque range, determining that the operating condition of the above engine is the above first operating condition; when the rotational speed of the above engine is less than the preset rotational speed and the torque of the above engine is less than the preset torque, determining that the operating condition of the above engine is the second operating condition, where the preset rotational speed is less than the lower limit value of the preset rotational speed range, the preset torque is less than the lower limit value of the preset torque range, and the second operating condition is the operating condition where the above engine is not started.

[0151] Obviously, those skilled in the art should understand that the above-mentioned modules or steps of the present invention can be implemented by a general-purpose computing device. They can be concentrated on a single computing device or distributed over a network composed of multiple computing devices. They can be implemented by program codes executable by the computing device. Thus, they can be stored in a storage device and executed by the computing device. And in some cases, the steps shown or described can be executed in a different order from here, or they can be separately made into individual integrated circuit modules, or multiple modules or steps among them can be made into a single integrated circuit module for implementation. In this way, the present invention is not limited to any specific combination of hardware and software.

[0152] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0153] The present application is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0154] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device that implements the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0155] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide for implementing the process Figure 1 one process or multiple processes and / or blocks Figure 1 steps of the functions specified in one block or multiple blocks.

[0156] In a typical configuration, a computing device includes one or more processors (CPUs), an input / output interface, a network interface, and memory.

[0157] The memory may include non-permanent memory in the computer-readable medium, in the form of random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash memory (flash RAM). The memory is an example of a computer-readable medium.

[0158] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology for information storage. The information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media 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 technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassette tapes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media, such as modulated data signals and carrier waves.

[0159] It should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, commodity or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, commodity or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, commodity or device comprising the element.

[0160] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0161] 1) The engine fault detection method of the present application includes: when the working condition of the above-mentioned engine is the first working condition, obtaining the above-mentioned methane concentration value, where the first working condition is the working condition of the normal operation of the above-mentioned engine; determining whether the above-mentioned methane concentration value is within a preset concentration range; when the above-mentioned methane concentration value is within the above-mentioned preset concentration range, determining that the above-mentioned engine has a ventilation fault, where the ventilation fault is a disconnection between the above-mentioned ventilation pipeline and the above-mentioned intake pipeline. Since when the engine is running normally, if the intake pipeline and the ventilation pipeline are well connected, the methane concentration value on the inner wall of the common end of the intake pipeline and the ventilation pipeline should be maintained within a certain concentration range. If it is determined that there is a disconnection between the gas pipeline and the ventilation pipeline, the methane concentration value on the inner wall of the common end of the intake pipeline and the ventilation pipeline should be significantly reduced. The controller determines that the methane concentration value detected by the methane sensor on the inner wall of the common end of the intake pipeline and the ventilation pipeline is within the preset concentration range, that is, it is determined that the methane concentration value on the inner wall of the common end of the intake pipeline and the ventilation pipeline is significantly reduced, and it can be determined that there is a disconnection between the gas pipeline and the ventilation pipeline, solving the problem that it is extremely easy to have false alarms or misreports of faults in determining the connection status of the ventilation pipeline and the intake pipeline according to the gas pressure change in the prior art.

[0162] 2) The controller of the present application includes: a first acquisition unit for obtaining the above-mentioned methane concentration value when the working condition of the engine is the first working condition, where the first working condition is the working condition of the normal operation of the above-mentioned engine; a first determination unit for determining whether the above-mentioned methane concentration value is within a second preset concentration range; a second determination unit for determining that the above-mentioned engine has a ventilation fault when the above-mentioned methane concentration value is within the above-mentioned second preset concentration range, where the ventilation fault is a disconnection between the above-mentioned ventilation pipeline and the above-mentioned intake pipeline. Since when the engine is running normally, if the intake pipeline and the ventilation pipeline are well connected, the methane concentration value on the inner wall of the common end of the intake pipeline and the ventilation pipeline should be maintained within a certain concentration range. If it is determined that there is a disconnection between the gas pipeline and the ventilation pipeline, the methane concentration value on the inner wall of the common end of the intake pipeline and the ventilation pipeline should be significantly reduced. The controller determines that the methane concentration value detected by the methane sensor on the inner wall of the common end of the intake pipeline and the ventilation pipeline is within the preset concentration range, that is, it is determined that the methane concentration value on the inner wall of the common end of the intake pipeline and the ventilation pipeline is significantly reduced, and it can be determined that there is a disconnection between the gas pipeline and the ventilation pipeline, solving the problem that it is extremely easy to have false alarms or misreports of faults in determining the connection status of the ventilation pipeline and the intake pipeline according to the gas pressure change in the prior art.

[0163] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An engine fault detection method, characterized in that, The engine includes a crankcase, an intake pipeline, a ventilation pipeline, a front oxygen sensor, and a cylinder. The front oxygen sensor is used to determine the air-fuel ratio, which is the ratio of the mass of air entering the cylinder to the mass of fuel entering the cylinder. The fuel includes methane. The intake port of the crankcase is communicated with one end of the intake pipeline, the other end of the intake pipeline is communicated with one end of the ventilation pipeline, the other end of the ventilation pipeline is communicated with the exhaust port of the crankcase, and a methane sensor is installed at the common end of the intake pipeline and the ventilation pipeline. The methane sensor is used to detect the methane concentration value on the inner wall of the common end of the intake pipeline and the ventilation pipeline. The front oxygen sensor and the methane sensor are respectively communicatively connected to a controller. The engine fault detection method applies the controller, and the method includes: When the operating condition of the engine is the first operating condition, obtain the methane concentration value. The first operating condition is the operating condition when the engine is running normally; determine whether the methane concentration value is within a preset concentration range; when the methane concentration value is within the preset concentration range, determine that the engine has a ventilation fault, and the ventilation fault is that the ventilation pipeline is disconnected from the intake pipeline; When the operating condition of the engine is the second operating condition, obtain the methane concentration value. The second operating condition is the operating condition when the engine is not started; determine whether the methane concentration value meets a second preset condition, and the second preset condition is that the methane concentration value is less than a first preset concentration value and the duration is greater than a second preset time, and the first preset concentration value is less than the lower limit of the preset concentration range; when the methane concentration value is less than the first preset concentration value, generate a second message, and the second message is a message indicating that the methane sensor is reliable; After determining whether the methane concentration value is within the preset concentration range, the method further includes: when the methane concentration value is not within the preset concentration range, determine whether the methane concentration value is less than a third preset concentration value, and the third preset concentration value is equal to the lower limit of the preset concentration range; when the methane concentration value is less than the third preset concentration value, obtain the air-fuel ratio and determine whether the air-fuel ratio is greater than a preset value; when the air-fuel ratio is greater than the preset value, generate a fourth message, and the fourth message is a message indicating that the ventilation fault cannot be detected.

2. The detection method according to claim 1, wherein After obtaining the methane concentration value, the method further includes: Determine whether the methane concentration value meets a first preset condition, and the first preset condition is that the methane concentration value is within the preset concentration range and the duration is greater than a first preset time; When the methane concentration value meets the first preset condition, determine that the engine has the ventilation fault and generate a first message, and the first message is a message indicating that the engine has the ventilation fault.

3. The method according to claim 1, wherein After determining whether the methane concentration value is within a preset concentration range, the method further includes: when the methane concentration value is not within the preset concentration range, determining whether the methane concentration value is greater than a second preset concentration value, where the second preset concentration value is greater than the upper limit of the preset concentration range; when the methane concentration value is greater than the second preset concentration value, generating a third message, where the third message is a message indicating that a misfire fault has occurred in the engine.

4. The method according to claim 1, wherein Before obtaining the methane concentration value, the method further includes: obtaining the intake air volume of the engine and the fuel injection volume of the engine; When the intake air volume of the engine is within a preset intake air volume range and the fuel injection volume of the engine is within a preset fuel injection volume range, determining that the operating condition of the engine is the first operating condition; when the intake air volume of the engine is less than the preset intake air volume and the fuel injection volume of the engine is less than the preset fuel injection volume, determining that the operating condition of the engine is the second operating condition, where the preset intake air volume is less than the lower limit of the preset intake air volume range, the preset fuel injection volume is less than the lower limit of the preset fuel injection volume range, and the second operating condition is the operating condition where the engine is not started.

5. The method according to claim 1, wherein Before obtaining the methane concentration value, the method further includes: obtaining the rotational speed of the engine and the torque of the engine; When the rotational speed of the engine is within a preset rotational speed range and the torque of the engine is within a preset torque range, determining that the operating condition of the engine is the first operating condition; when the rotational speed of the engine is less than the preset rotational speed and the torque of the engine is less than the preset torque, determining that the operating condition of the engine is the second operating condition, where the preset rotational speed is less than the lower limit of the preset rotational speed range, the preset torque is less than the lower limit of the preset torque range, and the second operating condition is the operating condition where the engine is not started.

6. A controller, the controller being configured to execute the engine fault detection method according to any one of claims 1 to 5, characterized in that, The controller includes: a first obtaining unit, configured to obtain the methane concentration value when the operating condition of the engine is the first operating condition, where the first operating condition is the operating condition where the engine is running normally; a first determining unit, configured to determine whether the methane concentration value is within a preset concentration range; a second determining unit, configured to determine that a ventilation fault has occurred in the engine when the methane concentration value is within the preset concentration range, where the ventilation fault is a disconnection between the ventilation pipeline and the intake pipeline.

7. An engine fault detection device, characterized in that, The engine fault detection device includes: a controller, where the controller is configured to execute the engine fault detection method according to any one of claims 1 to 5; an engine, where the engine includes a crankcase, an intake pipeline, a ventilation pipeline, a front oxygen sensor, and a cylinder. The intake port of the crankcase is communicated with one end of the intake pipeline, the other end of the intake pipeline is communicated with one end of the ventilation pipeline, the other end of the ventilation pipeline is communicated with the exhaust port of the crankcase, the front oxygen sensor is communicatively connected to the controller, and the front oxygen sensor is configured to determine the air-fuel ratio. A methane sensor, which is installed at the common end of the intake pipe and the ventilation pipe. The methane sensor is used to detect the methane concentration value on the inner wall of the common end of the intake pipe and the ventilation pipe, and the methane sensor is communicatively connected to a controller.

8. A detection system, characterized in that, The detection system includes the device according to claim 7 and a client, and the controller communicates with the client.

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