Tail gas treatment fault diagnosis method, device and working machine

Abstract

The application relates to the technical field of engine tail gas treatment, and provides a tail gas treatment fault diagnosis method, device and working machine, wherein the method comprises the following steps: in the case that the fuel liquid level of a target engine is monitored to be raised, acquiring the first conversion efficiency of a nitrogen oxide treatment device of the target engine; in the case that the first conversion efficiency is less than a preset threshold value, performing a sulfur removal operation on the nitrogen oxide treatment device; acquiring the second conversion efficiency of the nitrogen oxide treatment device of the target engine; in the case that the second conversion efficiency is less than the preset threshold value, determining that the nitrogen oxide treatment device is faulty, or in the case that the second conversion efficiency is greater than or equal to the preset threshold value, determining that the sulfide content in the fuel of the target engine is excessive. The method and device provided by the application can accurately determine whether the refueled fuel is excessive in sulfur in the early stage of refueling, and the exhaust emission quality of the engine is improved.

Description

Technical Field

[0001] This invention relates to the field of engine exhaust gas treatment technology, and in particular to an exhaust gas treatment fault diagnosis method, device and operating machinery. Background Technology

[0002] Diesel engines produce nitrogen oxides (NOx) during operation, which are emitted through the exhaust. With increasingly stringent requirements for energy conservation and environmental protection, a selective catalytic reduction (SCR) device can be added to the diesel engine's exhaust aftertreatment system. The SCR device is the core unit of the exhaust aftertreatment system. It works by injecting a measured amount of ammonia (NH3) from the high-temperature hydrolysis of urea, which reacts with NOx in the exhaust gas on the catalyst surface, thereby achieving emission reduction. The activity of the catalyst is crucial to the reaction and directly affects the conversion efficiency of the SCR device.

[0003] In existing technologies, periodic desulfurization is typically used in diesel engine aftertreatment systems to improve the conversion efficiency of SCR units. However, this method does not consider the true causes of catalyst activity reduction, cannot promptly improve the nitrogen oxide conversion efficiency of the SCR unit, and cannot effectively prevent SCR unit failure.

[0004] Therefore, accurately determining the reasons for the reduced conversion efficiency of nitrogen oxide treatment devices and improving the emission quality of engine exhaust has become a pressing technical problem for the industry. Summary of the Invention

[0005] This invention provides a method, apparatus, and machinery for diagnosing exhaust gas treatment faults, which addresses the technical problem of accurately determining the causes of reduced conversion efficiency in nitrogen oxide treatment devices and improving the emission quality of engine exhaust gases.

[0006] This invention provides a method for diagnosing exhaust gas treatment faults, comprising:

[0007] When a rise in the fuel level of the target engine is detected, the first conversion efficiency of the nitrogen oxide treatment device of the target engine is obtained.

[0008] If the first conversion efficiency is less than a preset threshold, the nitrogen oxide treatment device is subjected to desulfurization operation;

[0009] Obtain the second conversion efficiency of the nitrogen oxide treatment device of the target engine;

[0010] If the second conversion efficiency is less than a preset threshold, it is determined that the nitrogen oxide treatment device has malfunctioned; or, if the second conversion efficiency is greater than or equal to the preset threshold, it is determined that the sulfide content in the fuel of the target engine exceeds the standard.

[0011] In some embodiments, before obtaining the first conversion efficiency of the nitrogen oxide treatment device of the target engine upon detecting an increase in the fuel level of the target engine, the method further includes:

[0012] Obtain the fuel level of the target engine at the current moment;

[0013] Store the current fuel level in a non-volatile memory;

[0014] If the fuel level at the current moment is greater than the fuel level at the previous moment, it is determined that the fuel level of the target engine has increased.

[0015] In some embodiments, obtaining the first conversion efficiency of the nitrogen oxide treatment device of the target engine when a rise in the fuel level of the target engine is detected includes:

[0016] When the fuel level of the target engine is detected to rise, the first conversion efficiency of the nitrogen oxide treatment device of the target engine is obtained based on a preset delay time.

[0017] The preset delay time is based on the average time taken for multiple sample engines to run from a first moment to a second moment after being refueled with the target fuel; the first moment is the moment when the sample engine starts running after performing desulfurization operation on the nitrogen oxide treatment device; the second moment is the moment when the conversion efficiency of the nitrogen oxide treatment device of the sample engine is detected to drop to the conversion efficiency warning value; and the sulfur content in the target fuel exceeds the standard.

[0018] In some embodiments, performing a desulfurization operation on the nitrogen oxide treatment device when the first conversion efficiency is less than a preset threshold includes:

[0019] If the first conversion efficiency is less than a preset threshold, obtain the running time of the target engine or the running mileage of the working machinery to which the target engine belongs after the last desulfurization operation.

[0020] If the running time exceeds the preset running time or the running mileage exceeds the preset running mileage, the nitrogen oxide treatment device shall perform desulfurization operation.

[0021] In some embodiments, the desulfurization operation of the nitrogen oxide treatment device includes:

[0022] Obtain the cooling water temperature of the target engine and the inlet exhaust temperature of the particulate filter of the target engine;

[0023] When the cooling water temperature is greater than the preset water temperature and the inlet exhaust temperature is greater than the preset exhaust temperature, the regeneration temperature and regeneration time are determined.

[0024] The particle collector is regenerated based on the regeneration temperature and the regeneration time.

[0025] The exhaust gas from the particulate filter during regeneration is used to remove sulfides from the catalyst surface in the nitrogen oxide treatment device.

[0026] In some embodiments, after determining that the sulfide content in the fuel of the target engine exceeds the standard, the method further includes:

[0027] Generate fuel sulfur exceeding standard alarm information;

[0028] The alarm information regarding excessive sulfur in the fuel is sent to the instrument panel of the machine to which the target engine belongs.

[0029] This invention provides a device for diagnosing exhaust gas treatment faults, comprising:

[0030] The first acquisition unit is used to acquire the first conversion efficiency of the nitrogen oxide treatment device of the target engine when the fuel level of the target engine is detected to rise.

[0031] A desulfurization operation unit is used to perform desulfurization operation on the nitrogen oxide treatment device when the first conversion efficiency is less than a preset threshold.

[0032] The second acquisition unit is used to acquire the second conversion efficiency of the nitrogen oxide treatment device of the target engine;

[0033] The fault diagnosis unit is used to determine that the nitrogen oxide treatment device has malfunctioned when the second conversion efficiency is less than a preset threshold, or to determine that the sulfur content in the fuel of the target engine exceeds the standard when the second conversion efficiency is greater than or equal to the preset threshold.

[0034] The present invention provides a working machine, including the exhaust gas treatment fault diagnosis device.

[0035] The present invention provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the exhaust gas treatment fault diagnosis method.

[0036] The present invention provides a non-transitory computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the exhaust gas treatment fault diagnosis method.

[0037] The exhaust gas treatment fault diagnosis method, device, and operating machinery provided by this invention monitors the fuel level and performs desulfurization when the conversion efficiency of the nitrogen oxide treatment device decreases. Furthermore, it actively detects the conversion efficiency of the nitrogen oxide treatment device. Based on the detection results, it can accurately determine early in the refueling process whether the refueling fuel contains excessive sulfur or whether the nitrogen oxide treatment device itself is malfunctioning. This allows for timely alerts to the driver, preventing the continued damage to the nitrogen oxide treatment device caused by excessive sulfur fuel, thus improving the quality of engine exhaust emissions. Simultaneously, it eliminates the need for periodic desulfurization operations, allowing them to be performed only when a decrease in the conversion efficiency of the nitrogen oxide treatment device is detected. This effectively reduces fuel consumption for the operating machinery caused by periodic desulfurization operations, lowering the operating costs of the machinery. Attached Figure Description

[0038] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0039] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0040] Figure 1 This is one of the flowcharts of the exhaust gas treatment fault diagnosis method provided by the present invention;

[0041] Figure 2 This is the second flowchart of the exhaust gas treatment fault diagnosis method provided by the present invention;

[0042] Figure 3 This is a schematic flowchart of the desulfurization operation method provided by the present invention;

[0043] Figure 4 This is a schematic diagram of the exhaust gas treatment fault diagnosis device provided by the present invention;

[0044] Figure 5 This is a schematic diagram of the working machinery provided by the present invention;

[0045] Figure 6 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0047] It should be noted that the terms "first," "second," etc., used in this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or modules is not necessarily limited to those steps or modules explicitly listed, but may include other steps or modules not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0048] Many factors affect the conversion efficiency of SCR catalysts. For example, if the diesel engine uses low-quality fuel with many impurities, the resulting exhaust gas will contain more impurities that adhere to the surface of the SCR catalyst, reducing its activity. Similarly, excessive sulfur content in the fuel will produce ammonia sulfide, which will contaminate the SCR catalyst and also reduce its activity. Furthermore, malfunctions such as aging or damage to the SCR catalyst itself, abnormal urea injection, changes in vehicle operating conditions, and measurement errors in the sensors monitoring the SCR conversion efficiency can also reduce conversion efficiency.

[0049] Figure 1 This is one of the flowcharts of the exhaust gas treatment fault diagnosis method provided by the present invention, such as... Figure 1 As shown, the method includes steps 110, 120, 130 and 140.

[0050] Step 110: When the fuel level of the target engine is detected to rise, obtain the first conversion efficiency of the nitrogen oxide treatment device of the target engine.

[0051] Specifically, the entity executing the exhaust gas treatment fault diagnosis method provided in this embodiment of the invention is an exhaust gas treatment fault diagnosis device. This device can be implemented through software, such as an exhaust gas treatment fault diagnosis program running in the vehicle controller (Electronic Control Unit, ECU); or it can be a device executing the exhaust gas treatment fault diagnosis method, such as a vehicle controller or an on-board diagnostic system (OBD).

[0052] The method provided in this invention is applicable to construction machinery that uses diesel engines. The type of construction machinery is not limited; for example, it can be an excavator, crane, loader, etc. In other words, it is applicable as long as the construction machinery uses a diesel engine and is equipped with an exhaust aftertreatment system. The exhaust aftertreatment system generally includes a diesel oxidation catalytic converter (DOC), a diesel particulate filter (DPF), and a selective catalytic reduction (SCR) device.

[0053] The target engine is one that uses diesel or other similar fuels. During the engine's operation, the quality of exhaust emissions is directly related to the fuel used. If fuel with excessive sulfur content is used, the resulting ammonia sulfide will contaminate the surface of the SCR (Selective Catalytic Reduction) unit and reduce its conversion efficiency. Prolonged use of this type of fuel will lead to permanent failure of the SCR unit, rendering the exhaust aftertreatment system unable to treat harmful exhaust gases. Furthermore, since the SCR unit is generally integrated into the exhaust aftertreatment system and cannot be replaced separately, its permanent failure will cause significant economic losses to the entire exhaust aftertreatment system.

[0054] The fuel level of the target engine can be monitored. Specifically, this can be done by monitoring the fuel tank level in the machinery where the target engine is located. If the fuel level rises, it indicates that new fuel has been added to the machinery. In this case, the first conversion efficiency of the nitrogen oxide treatment device of the target engine can be obtained.

[0055] A nitrogen oxide (NOx) treatment device refers to the selective catalytic converter (SCR) unit in the exhaust aftertreatment system connected to the target engine. Conversion efficiency refers to the SCR unit's ability to react NOx entering the unit with a reducing agent (usually ammonia or urea solution) and convert it into harmless substances. Higher conversion efficiency means the SCR unit can more effectively convert NOx into harmless substances, thereby reducing pollutant emissions in the exhaust. Conversion efficiency is usually expressed as a percentage; for example, an SCR unit with a conversion efficiency of 90% means that the unit can convert 90% of NOx into harmless substances.

[0056] In exhaust aftertreatment systems, an upstream nitrogen oxide sensor is typically installed at the exhaust inlet (before the DOC device) to measure the nitrogen oxide content in the engine's raw exhaust (upstream); and a downstream nitrogen oxide sensor is installed at the exhaust outlet (after the SCR device) to measure the nitrogen oxide content in the engine's exhaust gas (downstream). The conversion efficiency of the nitrogen oxide treatment device can be calculated using the measurement results from these two nitrogen oxide sensors.

[0057] It should be noted that the initial conversion efficiency is obtained after refueling with new fuel. Because the effects of high-sulfur fuel on the SCR device are delayed, it may take some time for a noticeable impact to appear. On-board diagnostic systems typically test the conversion efficiency of the SCR device according to certain operating time or mileage requirements (also known as passive monitoring). Therefore, the initial conversion efficiency here can be obtained by the on-board diagnostic system testing the SCR device at set time intervals or mileage intervals.

[0058] Step 120: If the first conversion efficiency is less than a preset threshold, perform desulfurization operation on the nitrogen oxide treatment device.

[0059] Specifically, the preset threshold is a limit value for the conversion efficiency of the SCR device, such as 80%. If the conversion efficiency is greater than or equal to the preset threshold, the exhaust gas converted by the SCR device can be considered to meet the relevant exhaust gas emission requirements; if the conversion efficiency is less than the preset threshold, the exhaust gas converted by the SCR device can be considered to not meet the relevant exhaust gas emission requirements. The preset threshold can be set according to the relevant exhaust gas emission requirements.

[0060] If the initial conversion efficiency is less than a preset threshold, it indicates that the conversion efficiency of the SCR unit has decreased after refueling. In this case, the exhaust aftertreatment system can be triggered to perform desulfurization on the SCR unit.

[0061] Desulfurization is mainly achieved by triggering the regeneration of the DPF unit. The high-temperature exhaust gas during DPF regeneration removes sulfides from the SCR unit and other parts of the aftertreatment system.

[0062] Step 130: Obtain the second conversion efficiency of the nitrogen oxide treatment device of the target engine.

[0063] Specifically, after the desulfurization operation is completed, the second conversion efficiency of the nitrogen oxide treatment device of the target engine can be calculated using the measurement data from the nitrogen oxide sensor in the exhaust gas aftertreatment system.

[0064] It should be noted that the second conversion efficiency is obtained after the desulfurization operation is completed (also known as active monitoring), and is not obtained after the on-board diagnostic system tests the SCR device at set time intervals or mileage intervals.

[0065] The first and second conversion efficiencies may belong to different driving cycles. A driving cycle refers to the combination of time from engine start, (vehicle) operation, engine shutdown, and the time from engine shutdown to the next engine start. If the first conversion efficiency was acquired in the previous driving cycle and desulfurization was performed in the previous driving cycle, then upon entering the current driving cycle, the operation to acquire the second conversion efficiency can be triggered immediately.

[0066] Step 140: If the second conversion efficiency is less than a preset threshold, determine that the nitrogen oxide treatment device has malfunctioned; or, if the second conversion efficiency is greater than or equal to the preset threshold, determine that the sulfur content in the fuel of the target engine exceeds the standard.

[0067] Specifically, if the second conversion efficiency is less than a preset threshold, it indicates that although desulfurization was performed to remove sulfides from the catalyst, the conversion efficiency of the SCR unit was not effectively improved. This suggests a possible malfunction in the SCR unit itself, unrelated to fuel quality, such as aging, damage, abnormal urea injection, or sensor malfunction. In this case, an error can be reported through the on-board diagnostic system to alert the driver.

[0068] If the second conversion efficiency is greater than or equal to the preset threshold, it indicates that the SCR device's conversion efficiency has been effectively improved after the desulfurization operation. The reason for the decrease in the SCR device's conversion efficiency is that the sulfur content in the target engine's fuel exceeds the standard. In this case, the vehicle controller can send an error message indicating excessive sulfur content in the fuel to the instrument panel to alert the driver. Excessive sulfur content means that the sulfur content in the fuel exceeds the standard value specified in the relevant requirements.

[0069] Figure 2 This is a second schematic flowchart of the exhaust gas treatment fault diagnosis method provided by the present invention, as shown below. Figure 2 As shown, the method includes:

[0070] Step 210: Measure the fuel level using the fuel tank level gauge and compare it with the fuel level at the previous moment to determine that new fuel has been added.

[0071] Step 220: After the delay time, the first conversion efficiency is obtained based on the passive monitoring of the conversion efficiency of the SCR device;

[0072] Step 230: If the first conversion efficiency is greater than the preset threshold, it indicates that the SCR device is converting normally; if the first conversion efficiency is less than the preset threshold, it indicates that the SCR device is converting abnormally.

[0073] Step 240: In the event of an abnormal conversion in the SCR unit, trigger the desulfurization operation;

[0074] Step 250: Actively trigger the SCR device's conversion efficiency monitoring to obtain the second conversion efficiency;

[0075] Step 260: If the second conversion efficiency is greater than the preset threshold, it indicates that the SCR device is poisoned by sulfur, and a fuel sulfur exceeding the standard alarm is sent; if the second conversion efficiency is less than the preset threshold, it indicates that the SCR device has malfunctioned, and an SCR device malfunction alarm is sent.

[0076] The exhaust gas treatment fault diagnosis method provided in this embodiment of the invention, when detecting an increase in the fuel level of a target engine, obtains a first conversion efficiency of the nitrogen oxide treatment device of the target engine; if the first conversion efficiency is less than a preset threshold, performs a desulfurization operation on the nitrogen oxide treatment device; obtains a second conversion efficiency of the nitrogen oxide treatment device of the target engine; if the second conversion efficiency is less than the preset threshold, determines that the nitrogen oxide treatment device has malfunctioned, or if the second conversion efficiency is greater than or equal to the preset threshold, determines that the sulfur content in the fuel of the target engine exceeds the standard; because the fuel level is monitored, the nitrogen oxide treatment device... When the conversion efficiency of the nitrogen oxide treatment device decreases, a desulfurization operation is performed. Then, the conversion efficiency of the nitrogen oxide treatment device is actively monitored. Based on the monitoring results, it can be accurately determined early in the refueling process whether the refueling fuel contains excessive sulfur or whether the nitrogen oxide treatment device itself is malfunctioning. The driver can be promptly alerted to avoid the continuous damage to the nitrogen oxide treatment device caused by excessive sulfur fuel, thereby improving the quality of engine exhaust emissions. At the same time, periodic desulfurization operations can be avoided, and can be performed only when the conversion efficiency of the nitrogen oxide treatment device is detected to decrease. This can effectively reduce the fuel consumption of the operating machinery caused by periodic desulfurization operations and reduce the operating cost of the operating machinery.

[0077] It should be noted that each embodiment of the present invention can be freely combined, rearranged, or executed individually, and does not need to rely on or depend on a fixed execution order.

[0078] In some embodiments, prior to step 110, the method further includes:

[0079] Obtain the fuel level of the target engine at the current moment;

[0080] Store the current fuel level in non-volatile memory;

[0081] If the fuel level at the current moment is higher than the fuel level at the previous moment, determine that the fuel level of the target engine has increased.

[0082] Specifically, to detect whether the target engine in the operating machinery is fueled, it is necessary to monitor the fuel level, which means acquiring the fuel level at various times.

[0083] If the fuel level at the current moment is higher than the fuel level at the previous moment, it can be determined that the fuel level of the target engine has increased, and it can also be determined that the working machinery has been refueled with new fuel.

[0084] For example, the vehicle controller and instruments of the operating machinery can exchange information via the Controller Area Network (CAN) bus. The vehicle controller can add a message field and node to receive the current fuel level from the instruments in the fuel tank and store it in non-volatile memory. Non-volatile memory has the characteristic of data retention after power failure, allowing the fuel level to be stored both before and after power failure, even if the vehicle controller is completely powered off. This maintains continuous monitoring of the fuel level and enables accurate determination of whether the operating machinery has been refueled.

[0085] The exhaust gas treatment fault diagnosis method provided in this embodiment of the invention determines whether new fuel has been added by monitoring changes in fuel level at various times, and stores the fuel level at various times using a non-volatile memory, thus maintaining continuous monitoring of the fuel level and improving the accuracy of fuel addition judgment.

[0086] In some embodiments, step 110 includes:

[0087] When the fuel level of the target engine is detected to rise, the first conversion efficiency of the nitrogen oxide treatment device of the target engine is obtained based on a preset delay time.

[0088] The preset delay time is based on the average time taken for multiple sample engines to run from the first moment to the second moment after the target fuel is added; the first moment is the moment when the sample engine starts running after the nitrogen oxide treatment device performs desulfurization operation; the second moment is the moment when the conversion efficiency of the nitrogen oxide treatment device of the sample engine is detected to drop to the conversion efficiency warning value; and the sulfur content in the target fuel exceeds the standard.

[0089] Specifically, the inferior fuel added will generally not have a significant impact on the conversion efficiency of the SCR device in the short term due to the different degrees of fuel deterioration and the dilution effect of the normal fuel remaining in the tank before addition. As a result, the on-board diagnostic system may not be able to detect it for a short period of time. In other words, the effect of the added fuel on the SCR device has a lag.

[0090] If a rise in the fuel level of the target engine is detected, the first conversion efficiency of the nitrogen oxide treatment device of the target engine can be obtained after a preset delay period.

[0091] The preset delay duration can be obtained by statistically analyzing the operating data of multiple sample engines. The sample engines can be diesel engines in machinery refueling the target fuel. The preset delay duration is the time between the first and second moments. The first moment is the time when the sample engine starts operating after performing desulfurization on the nitrogen oxide treatment device in the exhaust aftertreatment system; the second moment is the time when the conversion efficiency of the nitrogen oxide treatment device of the sample engine is detected to have dropped to the conversion efficiency warning value. The conversion efficiency warning value is used to trigger periodic desulfurization operations in the aftertreatment system and can be set to 90%.

[0092] For example, tracking tests on multiple vehicles whose SCR (Self-Recovery Catalytic Reduction) devices suffered from "sulfur poisoning" due to the use of substandard fuel revealed that after high-temperature regeneration and desulfurization, the SCR device's conversion efficiency was close to 100%. However, after continuing to operate the vehicle with substandard fuel, the conversion efficiency dropped to around 95% after approximately 3-4 hours, to around 90% (the conversion efficiency warning value) after about 8 hours, and to below 80% after 20 hours (80% being a preset threshold). At this point, the exhaust emissions from the aftertreatment system no longer met the relevant requirements. Therefore, to trigger fuel quality detection in the shortest possible time and reduce continued damage to the SCR device, the vehicle should be run for another 8 hours after refueling. At this point, the SCR device's conversion efficiency is just close to the conversion efficiency warning value (the passive monitoring limit for SCR device efficiency), allowing the desulfurization function to be triggered while the fault is being reported normally. It cannot be triggered immediately after refueling, as the efficiency is not yet affected. The higher the sulfur content in the substandard fuel, the shorter the trigger time for the desulfurization function.

[0093] The exhaust gas treatment fault diagnosis method provided in this embodiment of the invention improves the accuracy of first conversion efficiency detection by delaying the acquisition of the first conversion efficiency of the nitrogen oxide treatment device when the fuel level of the target engine is detected to rise.

[0094] In some embodiments, step 120 includes:

[0095] If the first conversion efficiency is less than a preset threshold, obtain the running time of the target engine or the running mileage of the machinery to which the target engine belongs after the last desulfurization operation;

[0096] When the operating time exceeds the preset operating time or the operating mileage exceeds the preset operating mileage, the nitrogen oxide treatment device shall be subjected to desulfurization operation.

[0097] Specifically, performing desulfurization on the nitrogen oxide treatment unit when the first conversion efficiency is less than a preset threshold is a condition for triggering the desulfurization operation by using the passive monitoring fault of the SCR unit's conversion efficiency.

[0098] If the target engine's operating time is short after the previous desulfurization operation, or the operating mileage of the machinery using the target engine is low, triggering another desulfurization operation would result in excessively frequent operations, increasing fuel consumption. Therefore, a preset operating time or preset operating mileage can be set to limit the number of desulfurization operations. Desulfurization will only be triggered when the operating time exceeds the preset operating time or the operating mileage exceeds the preset operating mileage. The preset operating time and preset operating mileage can be set as needed.

[0099] The exhaust gas treatment fault diagnosis method provided in this embodiment of the invention, when the first conversion efficiency is less than a preset threshold, triggers the desulfurization operation of the nitrogen oxide treatment device by setting a preset running time and a preset running mileage, so as to avoid the desulfurization operation being too frequent and reduce the fuel consumption of the working machinery for the desulfurization operation.

[0100] In some embodiments, performing a desulfurization operation on a nitrogen oxide treatment device includes:

[0101] Obtain the cooling water temperature and the inlet exhaust temperature of the target engine's particulate filter;

[0102] When the cooling water temperature is higher than the preset water temperature and the inlet exhaust temperature is higher than the preset exhaust temperature, determine the regeneration temperature and regeneration time.

[0103] The regeneration of the particle collector is controlled based on the regeneration temperature and regeneration time.

[0104] The exhaust gas from the particulate filter during regeneration is used to remove sulfides from the catalyst surface in the nitrogen oxide treatment unit.

[0105] Specifically, the desulfurization operation of the nitrogen oxide treatment unit is mainly achieved through the regeneration of the particulate filter.

[0106] Before controlling the regeneration of the particulate filter, it is necessary to obtain the cooling water temperature and the inlet exhaust temperature of the particulate filter of the target engine.

[0107] The preset water temperature and preset exhaust temperature are the conditions that the particulate filter needs to meet for regeneration, and can be set as needed.

[0108] When the cooling water temperature and the inlet exhaust temperature are both higher than the preset water temperature and the inlet exhaust temperature, the regeneration temperature and regeneration time can be set. For example, the regeneration temperature can be set to 500 degrees Celsius and the regeneration time can be set to 1200 seconds. Since the exhaust gas from the particulate filter during regeneration can be used to remove sulfides from the catalyst surface in the nitrogen oxide treatment unit, the regeneration time can also be understood as the desulfurization time.

[0109] A timer can be set to measure the regeneration time. After the timer expires, an RS trigger can be set to reset the desulfurization status of the nitrogen oxide treatment device. At this time, the post-treatment system ends the desulfurization operation (particulate matter collector regeneration).

[0110] Figure 3 This is a schematic flowchart of the desulfurization operation method provided by the present invention, as shown below. Figure 3 As shown, the method includes:

[0111] Step 310: Report a low efficiency fault in the SCR device;

[0112] Step 320: Determine that the engine's operating time is greater than the preset operating time, the operating mileage of the working machinery is greater than the preset operating mileage, and determine that there are no other related faults that prohibit regeneration in the system;

[0113] Step 330: Issue a particulate filter regeneration request to trigger the particulate filter to enter the regeneration state;

[0114] Step 340: Determine that the engine coolant temperature is greater than the preset coolant temperature and the inlet exhaust temperature of the particulate filter is greater than the preset exhaust temperature.

[0115] Step 350: Control the regeneration of the particulate filter according to the set regeneration temperature and regeneration time. The exhaust gas at the outlet of the particulate filter during regeneration is used to remove sulfides from the surface of the catalyst in the nitrogen oxide treatment unit.

[0116] The exhaust gas treatment fault diagnosis method provided in this embodiment of the invention limits the regeneration of the particulate filter by controlling the engine's cooling water temperature and the inlet exhaust temperature of the particulate filter, thereby improving the implementation effect of desulfurization operation.

[0117] In some embodiments, after step 140, the method further includes:

[0118] Generate fuel sulfur exceeding standard alarm information;

[0119] The alarm message indicating excessive sulfur in the fuel is sent to the instrument panel of the machine to which the target engine belongs.

[0120] Specifically, if it is determined that the sulfur content in the fuel of the target engine exceeds the standard, a fuel sulfur exceeding the standard alarm message can be generated and sent to the instrument panel of the operating machinery to remind the driver through lights or sound.

[0121] The exhaust gas treatment fault diagnosis method provided in this embodiment of the invention provides a fuel sulfur exceeding standard alarm prompt to the driver on the instrument panel, which improves the driver's user experience.

[0122] The apparatus provided in the embodiments of the present invention will be described below. The apparatus described below can be referred to in correspondence with the method described above.

[0123] Figure 4 This is a schematic diagram of the exhaust gas treatment fault diagnosis device provided by the present invention, as shown below. Figure 4 As shown, the device 400 includes:

[0124] The first acquisition unit 410 is used to acquire the first conversion efficiency of the nitrogen oxide treatment device of the target engine when the fuel level of the target engine is detected to rise.

[0125] The desulfurization operation unit 420 is used to perform desulfurization operation on the nitrogen oxide treatment device when the first conversion efficiency is less than a preset threshold.

[0126] The second acquisition unit 430 is used to acquire the second conversion efficiency of the nitrogen oxide treatment device of the target engine;

[0127] The fault diagnosis unit 440 is used to determine that the nitrogen oxide treatment device has malfunctioned when the second conversion efficiency is less than a preset threshold, or to determine that the sulfur content in the fuel of the target engine exceeds the standard when the second conversion efficiency is greater than or equal to the preset threshold.

[0128] The exhaust gas treatment fault diagnosis device provided in this embodiment of the invention, when detecting an increase in the fuel level of a target engine, obtains a first conversion efficiency of the nitrogen oxide treatment device of the target engine; if the first conversion efficiency is less than a preset threshold, performs a desulfurization operation on the nitrogen oxide treatment device; obtains a second conversion efficiency of the nitrogen oxide treatment device of the target engine; if the second conversion efficiency is less than the preset threshold, determines that the nitrogen oxide treatment device has malfunctioned, or if the second conversion efficiency is greater than or equal to the preset threshold, determines that the sulfur content in the fuel of the target engine exceeds the standard; because the fuel level is monitored, the nitrogen oxide treatment device... When the conversion efficiency of the nitrogen oxide treatment device decreases, a desulfurization operation is performed. Then, the conversion efficiency of the nitrogen oxide treatment device is actively monitored. Based on the monitoring results, it can be accurately determined early in the refueling process whether the refueling fuel contains excessive sulfur or whether the nitrogen oxide treatment device itself is malfunctioning. The driver can be promptly alerted to avoid the continuous damage to the nitrogen oxide treatment device caused by excessive sulfur fuel, thereby improving the quality of engine exhaust emissions. At the same time, periodic desulfurization operations can be avoided, and can be performed only when the conversion efficiency of the nitrogen oxide treatment device is detected to decrease. This can effectively reduce the fuel consumption of the operating machinery caused by periodic desulfurization operations and reduce the operating cost of the operating machinery.

[0129] In some embodiments, the device further includes:

[0130] The fuel level monitoring unit is used to obtain the fuel level of the target engine at the current moment;

[0131] Store the current fuel level in non-volatile memory;

[0132] If the fuel level at the current moment is higher than the fuel level at the previous moment, determine that the fuel level of the target engine has increased.

[0133] In some embodiments, the first acquisition unit is specifically used for:

[0134] When the fuel level of the target engine is detected to rise, the first conversion efficiency of the nitrogen oxide treatment device of the target engine is obtained based on a preset delay time.

[0135] The preset delay time is based on the average time taken for multiple sample engines to run from the first moment to the second moment after the target fuel is added; the first moment is the moment when the sample engine starts running after the nitrogen oxide treatment device performs desulfurization operation; the second moment is the moment when the conversion efficiency of the nitrogen oxide treatment device of the sample engine is detected to drop to the conversion efficiency warning value; and the sulfur content in the target fuel exceeds the standard.

[0136] In some embodiments, the desulfurization operation unit is specifically used for:

[0137] If the first conversion efficiency is less than a preset threshold, obtain the running time of the target engine or the running mileage of the machinery to which the target engine belongs after the last desulfurization operation;

[0138] When the operating time exceeds the preset operating time or the operating mileage exceeds the preset operating mileage, the nitrogen oxide treatment device shall be subjected to desulfurization operation.

[0139] In some embodiments, the desulfurization operation unit is specifically used for:

[0140] Obtain the cooling water temperature and the inlet exhaust temperature of the target engine's particulate filter;

[0141] When the cooling water temperature is higher than the preset water temperature and the inlet exhaust temperature is higher than the preset exhaust temperature, determine the regeneration temperature and regeneration time.

[0142] The regeneration of the particle collector is controlled based on the regeneration temperature and regeneration time.

[0143] The exhaust gas from the particulate filter during regeneration is used to remove sulfides from the catalyst surface in the nitrogen oxide treatment unit.

[0144] In some embodiments, the device further includes:

[0145] The fuel alarm unit is used to generate alarm information for excessive sulfur content in fuel.

[0146] The alarm message indicating excessive sulfur in the fuel is sent to the instrument panel of the machine to which the target engine belongs.

[0147] Figure 5 This is a schematic diagram of the structure of the operating machinery provided by the present invention, as shown below. Figure 5 As shown, the working machine 500 includes the exhaust gas treatment fault diagnosis device 400 in the above embodiment.

[0148] Specifically, the types of operating machinery in the embodiments of the present invention are not limited. For example, operating machinery may include heavy trucks, trailers, excavators, anchor boring machines, bulldozers, road rollers and concrete pump trucks, or mechanical operating equipment such as tower cranes, construction hoists and material hoists.

[0149] The operating machinery provided in this embodiment of the invention has the advantages of high emission quality of engine exhaust gas and low fuel consumption in desulfurization operation due to the exhaust gas treatment fault diagnosis device as described above, resulting in low operating costs.

[0150] Figure 6 This is a schematic diagram of the structure of an electronic device provided in one embodiment of the present invention, as shown below. Figure 6As shown, the electronic device may include: a processor 610, a communications interface 620, a memory 630, and a communications bus 640, wherein the processor 610, the communications interface 620, and the memory 630 communicate with each other via the communications bus 640. The processor 610 can call logical commands in the memory 630 to execute the following methods:

[0151] If the fuel level of the target engine is detected to rise, the first conversion efficiency of the nitrogen oxide treatment device of the target engine is obtained; if the first conversion efficiency is less than a preset threshold, the nitrogen oxide treatment device is subjected to desulfurization operation; the second conversion efficiency of the nitrogen oxide treatment device of the target engine is obtained; if the second conversion efficiency is less than the preset threshold, it is determined that the nitrogen oxide treatment device has malfunctioned, or if the second conversion efficiency is greater than or equal to the preset threshold, it is determined that the sulfur content in the fuel of the target engine exceeds the standard.

[0152] Furthermore, the logical commands in the aforementioned memory can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several commands to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0153] The processor in the electronic device provided in this embodiment of the invention can call logical instructions in the memory to implement the above method. Its specific implementation method is the same as the aforementioned method implementation method and can achieve the same beneficial effects, which will not be repeated here.

[0154] This invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to perform the methods provided in the above embodiments.

[0155] The specific implementation method is the same as the aforementioned method implementation method and can achieve the same beneficial effects, so it will not be repeated here.

[0156] This invention provides a computer program product, including a computer program that, when executed by a processor, implements the method described above.

[0157] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0158] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0159] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for diagnosing exhaust gas treatment faults, characterized in that, include: When a rise in the fuel level of the target engine is detected, the first conversion efficiency of the nitrogen oxide treatment device of the target engine is obtained based on a preset delay time. The preset delay time is the average time taken for multiple sample engines to run from a first moment to a second moment after the target fuel is added. The first moment is the moment when the sample engine starts running after the nitrogen oxide treatment device performs desulfurization. The second moment is the moment when the conversion efficiency of the nitrogen oxide treatment device of the sample engine is detected to drop to a warning value. The sulfur content in the target fuel exceeds the standard. If the first conversion efficiency is less than a preset threshold, obtain the running time of the target engine or the running mileage of the working machinery to which the target engine belongs after the last desulfurization operation. If the running time is greater than the preset running time or the running mileage is greater than the preset running mileage, the cooling water temperature of the target engine and the inlet exhaust temperature of the particulate filter of the target engine are obtained. When the cooling water temperature is greater than the preset water temperature and the inlet exhaust temperature is greater than the preset exhaust temperature, the regeneration temperature and regeneration time are determined. The particle collector is regenerated based on the regeneration temperature and the regeneration time. The exhaust gas from the particulate filter during regeneration is used to remove sulfides from the catalyst surface in the nitrogen oxide treatment device. Obtain the second conversion efficiency of the nitrogen oxide treatment device of the target engine; If the second conversion efficiency is less than a preset threshold, it is determined that the nitrogen oxide treatment device has malfunctioned; or, if the second conversion efficiency is greater than or equal to the preset threshold, it is determined that the sulfide content in the fuel of the target engine exceeds the standard.

2. The exhaust gas treatment fault diagnosis method according to claim 1, characterized in that, Before obtaining the first conversion efficiency of the nitrogen oxide treatment device of the target engine when a rise in the fuel level of the target engine is detected, the method further includes: Obtain the fuel level of the target engine at the current moment; Store the current fuel level in a non-volatile memory; If the fuel level at the current moment is greater than the fuel level at the previous moment, it is determined that the fuel level of the target engine has increased.

3. The exhaust gas treatment fault diagnosis method according to claim 1, characterized in that, After determining that the sulfide content in the fuel of the target engine exceeds the standard, the method further includes: Generate fuel sulfur exceeding standard alarm information; The alarm information regarding excessive sulfur in the fuel is sent to the instrument panel of the machine to which the target engine belongs.

4. A device for diagnosing exhaust gas treatment faults, characterized in that, The device is used to implement the exhaust gas treatment fault diagnosis method according to any one of claims 1-3, the device comprising: The first acquisition unit is used to acquire the first conversion efficiency of the nitrogen oxide treatment device of the target engine when the fuel level of the target engine is detected to rise. A desulfurization operation unit is used to perform desulfurization operation on the nitrogen oxide treatment device when the first conversion efficiency is less than a preset threshold. The second acquisition unit is used to acquire the second conversion efficiency of the nitrogen oxide treatment device of the target engine; The fault diagnosis unit is used to determine that the nitrogen oxide treatment device has malfunctioned when the second conversion efficiency is less than a preset threshold, or to determine that the sulfur content in the fuel of the target engine exceeds the standard when the second conversion efficiency is greater than or equal to the preset threshold.

5. A type of operating machinery, characterized in that, Includes the exhaust gas treatment fault diagnosis device as described in claim 4.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the exhaust gas treatment fault diagnosis method as described in any one of claims 1 to 3.

7. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the exhaust gas treatment fault diagnosis method as described in any one of claims 1 to 3.

Images