CN119801706A

CN119801706A - Three-way catalytic converter ammonia leakage detection method, related device and electronic equipment

Info

Publication number: CN119801706A
Application number: CN202510043959.1A
Authority: CN
Inventors: 滕召威; 王金平; 郭明春; 蔡生青; 曲怡霖; 曲道骁
Original assignee: Weichai Power Co Ltd
Current assignee: Weichai Power Co Ltd
Priority date: 2025-01-10
Filing date: 2025-01-10
Publication date: 2025-04-11
Anticipated expiration: 2045-01-10
Also published as: CN119801706B

Abstract

The present application provides a method for detecting ammonia leakage in a three-way catalytic converter, a related device and an electronic device, the method comprising: an acquisition step, when the vehicle is in a steady-state condition and the oxygen concentration data detected by the nitrogen oxide sensor is greater than a preset value, acquiring the time proportion and oxygen concentration distribution of the oxygen concentration data in a window less than a first threshold; a first determination step, determining whether the time proportion is greater than a second threshold and whether the oxygen concentration distribution is less than a third threshold; a second determination step, when the time proportion is greater than the second threshold and the oxygen concentration distribution is less than the third threshold, determining that ammonia leakage occurs in the three-way catalytic converter; a third determination step, when the time proportion is less than or equal to the second threshold or the oxygen concentration distribution is greater than or equal to the third threshold, determining that ammonia leakage does not occur in the three-way catalytic converter. The present application solves the problem that ammonia leakage in a three-way catalytic converter cannot be accurately identified in the prior art.

Description

Method for detecting ammonia leakage of three-way catalyst, related device and electronic equipment

Technical Field

The application relates to the technical field of ammonia leakage monitoring, in particular to a method and a device for detecting ammonia leakage of a three-way catalyst, a computer readable storage medium, a computer program product and electronic equipment.

Background

In the current exhaust gas treatment system of a vehicle, detection of ammonia leakage in the three-way catalyst mainly depends on some traditional sensors, but the traditional sensors have limited precision, so that it is difficult to accurately identify the condition of ammonia leakage in the three-way catalyst.

Disclosure of Invention

The main object of the present application is to provide a method, a device, a computer readable storage medium, a computer program product and an electronic device for detecting ammonia leakage of a three-way catalyst, so as to at least solve the problem that it is difficult to accurately identify the ammonia leakage in the three-way catalyst in the prior art.

In order to achieve the above object, according to one aspect of the present application, there is provided a method for detecting ammonia leakage of a three-way catalyst in a vehicle, the method comprising an acquisition step of acquiring, when the vehicle is in a steady-state condition and oxygen concentration data detected by a nitrogen oxide sensor is greater than a preset value, a time ratio of the oxygen concentration data to be smaller than a first threshold value and an oxygen concentration distribution within a window, the window being a preset period of time or a period of time required for an engine to perform a preset work, the nitrogen oxide sensor being mounted in an exhaust pipe of the three-way catalyst, the oxygen concentration data being an oxygen concentration of exhaust gas in the exhaust pipe of the three-way catalyst, the oxygen concentration distribution being a distribution of the oxygen concentration data within the window, a first determination step of determining whether the time ratio is greater than a second threshold value and whether the oxygen concentration distribution is smaller than a third threshold value, a second determination step of time ratio being greater than the second threshold value and the oxygen concentration distribution is smaller than the third threshold value, the ammonia concentration distribution being determined to be greater than or equal to the third threshold value, the ammonia concentration being not being equal to the three-way catalyst, the ammonia concentration being determined to be greater than the third threshold value.

Optionally, the method further comprises the steps of obtaining the number of windows which are not leaked with ammonia under the condition that the three-way catalyst is not leaked with ammonia, wherein the operation conditions of the vehicles corresponding to different windows are the same, adjusting the air-fuel ratio set value of the engine in the vehicle under the condition that the number of windows which are not leaked with ammonia is larger than or equal to a fourth threshold value, enabling the air-fuel ratio set value after adjustment to be larger than the air-fuel ratio set value before adjustment, obtaining the oxygen concentration data after adjustment of the air-fuel ratio set value, and determining whether the three-way catalyst is leaked with ammonia according to the size relation between the oxygen concentration data after adjustment of the air-fuel ratio set value and the oxygen concentration data before adjustment of the air-fuel ratio set value.

Optionally, according to the magnitude relation between the oxygen concentration data after adjusting the air-fuel ratio setting value and the oxygen concentration data before adjusting the air-fuel ratio setting value, at least determining whether ammonia leakage occurs in the three-way catalyst includes a third determining step of determining that ammonia leakage occurs in the three-way catalyst when the oxygen concentration data after adjusting the air-fuel ratio setting value is smaller than the oxygen concentration data before adjusting the air-fuel ratio setting value, and determining that ammonia leakage does not occur in the three-way catalyst when the oxygen concentration data after adjusting the air-fuel ratio setting value is greater than or equal to the oxygen concentration data before adjusting the air-fuel ratio setting value, and an adjusting step of continuing adjusting the air-fuel ratio setting value such that the current adjusting direction of the air-fuel ratio setting value is the same as the previous adjusting direction when determining that ammonia leakage occurs in the three-way catalyst, and the current adjusting direction is opposite to the previous adjusting direction when determining that ammonia leakage does not occur in the three-way catalyst, and a first circulating step of circulating the third determining step and the adjusting step for a predetermined times.

Optionally, the method comprises the steps of obtaining the number of windows in which ammonia leakage does not occur under the condition that the three-way catalyst is not determined to occur, wherein the method comprises the steps of counting, controlling a count value to be increased by 1 under the condition that the three-way catalyst is determined to not occur, and performing a second circulation step to circularly execute the obtaining step, the first determining step, the second determining step and the counting step to obtain the number of windows in which ammonia leakage does not occur.

Optionally, adjusting the air-fuel ratio setting of the engine in the vehicle includes adjusting a fuel injector injection time of the vehicle or adjusting a throttle opening of the vehicle to adjust the air-fuel ratio setting of the engine in the vehicle.

Optionally, before the step of acquiring, the method further comprises acquiring a steady state determination parameter, wherein the steady state determination parameter comprises at least part of a rotational speed of the engine, a rotational speed change rate, an intake charge of the engine, an intake charge change rate, a water temperature of the engine, a temperature of the three-way catalyst, a mass flow rate of exhaust gas in the exhaust pipe, an operating state of the nitrogen oxide sensor and an operating state of the vehicle, and determining that the vehicle is in the steady state operating state when the steady state determination parameter meets a preset condition, and the preset condition comprises at least part of the rotational speed in a first preset range, the rotational speed change rate in a second preset range, the intake charge in a third preset range, the intake charge change rate in a fourth preset range, the water temperature in a fifth preset range, the temperature in a sixth preset range, the mass flow rate in a seventh preset range, the nitrogen oxide sensor is in a normal operating state and the vehicle is in a normal operating state.

According to another aspect of the application, a detection device for ammonia leakage of a three-way catalyst is provided, wherein the three-way catalyst is located in a vehicle, the device comprises a first acquisition unit, a first determination unit and a second determination unit, wherein the first acquisition unit is used for acquiring a time proportion and an oxygen concentration distribution of oxygen concentration data detected by a nitrogen oxide sensor in a window when the vehicle is in a steady-state working condition and the oxygen concentration data detected by the nitrogen oxide sensor is larger than a preset value, the window is a preset time period or a time period required by an engine to complete preset work, the nitrogen oxide sensor is installed in an exhaust pipe of the three-way catalyst, the oxygen concentration data is the oxygen concentration of exhaust gas in the three-way catalyst, the oxygen concentration data is the distribution condition of the oxygen concentration data in the window, the first determination unit is used for determining whether the time proportion is larger than a second threshold and the oxygen concentration data is smaller than a third threshold, the second determination unit is used for determining whether the time proportion is larger than the second threshold and the oxygen concentration data is smaller than the third threshold, the time proportion is larger than the second determination unit is used for determining that the time proportion is larger than the second threshold and the oxygen concentration data is smaller than the third threshold, the time proportion is equal to the time proportion is smaller than the third threshold or equal to the three-way catalyst is determined that the ammonia leakage is smaller than the third threshold or equal to the three-way catalyst.

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

According to a further aspect of the application there is provided a computer program product comprising computer instructions which when executed by a processor implement any of the methods described.

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

By applying the technical scheme of the application, firstly, under the condition that the vehicle is in a steady-state working condition and the oxygen concentration data detected by the nitrogen oxide sensor is larger than a preset value, the time duty ratio and the oxygen concentration distribution of the oxygen concentration data smaller than a first threshold value in a window are obtained, then whether the time duty ratio is larger than a second threshold value and whether the oxygen concentration distribution is smaller than a third threshold value are determined, under the condition that the time duty ratio is larger than the second threshold value and the oxygen concentration distribution is smaller than the third threshold value, the ammonia leakage of the three-way catalyst is determined, and under the condition that the time duty ratio is smaller than or equal to the second threshold value or the oxygen concentration distribution is larger than or equal to the third threshold value, the ammonia leakage of the three-way catalyst is determined. According to the oxygen concentration data and the oxygen concentration distribution condition measured by the nitrogen oxide sensor in one window, whether the three-way catalyst leaks ammonia or not is determined, and the effect of accurately identifying whether the three-way catalyst leaks ammonia or not is achieved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:

fig. 1 is a block diagram showing a hardware configuration of a mobile terminal for performing a method of detecting ammonia leakage of a three-way catalyst according to an embodiment of the present application;

FIG. 2 shows a schematic flow chart of a method for detecting ammonia slip from a three-way catalyst according to an embodiment of the present application;

FIG. 3 illustrates a flow chart of a method for detecting ammonia slip from a three-way catalyst provided in accordance with an embodiment of the present application;

Fig. 4 shows a schematic diagram of a detection device for ammonia leakage of a three-way catalyst according to an embodiment of the present application.

Wherein the above figures include the following reference numerals:

102. Processor, 104, memory, 106, transmission equipment, 108, input and output equipment.

Detailed Description

It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be combined with each other. The application will be described in detail below with reference to the drawings in connection with embodiments.

In order that those skilled in the art will better understand the present application, a technical solution in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present application without making any inventive effort, shall fall within the scope of the present application.

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

As described in the background art, in order to solve the above technical problems, embodiments of the present application provide a method for detecting ammonia leakage of a three-way catalyst, a detection device, a computer-readable storage medium, a computer program product, and an electronic device, in which it is difficult for a conventional sensor in the prior art to accurately identify the ammonia leakage in the three-way catalyst.

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

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

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

In the present embodiment, a method of detecting ammonia leakage of a three-way catalyst operating in a mobile terminal, a computer terminal, or a similar computing device is provided, it being noted that the steps shown in the flowchart of the drawings may be performed in a computer system such as a set of computer executable instructions, and although a logical sequence is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than that shown herein.

Fig. 2 is a flow chart of a method of detecting ammonia slip from a three-way catalyst according to an embodiment of the present application. As shown in fig. 2, the method comprises the steps of:

Step S201, acquiring, namely acquiring a time ratio and oxygen concentration distribution of the oxygen concentration data smaller than a first threshold value in a window when the vehicle is in a steady-state working condition and the oxygen concentration data detected by a nitrogen oxide sensor is larger than a preset value, wherein the window is a preset time period or a time period required by an engine to complete preset work, the nitrogen oxide sensor is arranged in an exhaust pipe of the three-way catalyst, the oxygen concentration data is the oxygen concentration of exhaust gas in the exhaust pipe of the three-way catalyst, and the oxygen concentration distribution is the distribution condition of the oxygen concentration data in the window;

Specifically, the nox sensor has cross sensitivity to nox and ammonia, and cannot effectively distinguish whether the read value is nox or ammonia. The nitrogen oxide sensor can measure the oxygen concentration in the tail gas, and the current emission type can be intuitively judged according to the oxygen signal measured by the nitrogen oxide sensor, so that the ammonia window can be effectively identified according to the oxygen concentration. The engine finishes the preset work, namely the engine works normally according to the design requirement, and the preset output power and efficiency are achieved, so that the vehicle is driven to run.

Step S202, a first determining step of determining whether the time duty ratio is greater than a second threshold value and whether the oxygen concentration distribution is less than a third threshold value;

And step S203, a second determining step, wherein when the time duty ratio is larger than the second threshold value and the oxygen concentration distribution is smaller than the third threshold value, the ammonia leakage of the three-way catalyst is determined, and when the time duty ratio is smaller than or equal to the second threshold value or the oxygen concentration distribution is larger than or equal to the third threshold value, the ammonia leakage of the three-way catalyst is determined not to occur.

According to the embodiment, firstly, under the condition that the vehicle is in a steady-state working condition and oxygen concentration data detected by a nitrogen oxide sensor is larger than a preset value, a time duty ratio and oxygen concentration distribution of the oxygen concentration data smaller than a first threshold value in a window are obtained, then whether the time duty ratio is larger than a second threshold value and whether the oxygen concentration distribution is smaller than a third threshold value are determined, under the condition that the time duty ratio is larger than the second threshold value and the oxygen concentration distribution is smaller than the third threshold value, ammonia leakage of the three-way catalyst is determined, and under the condition that the time duty ratio is smaller than or equal to the second threshold value or the oxygen concentration distribution is larger than or equal to the third threshold value, no ammonia leakage of the three-way catalyst is determined. According to the oxygen concentration data and the oxygen concentration distribution condition measured by the nitrogen oxide sensor in one window, whether the three-way catalyst leaks ammonia or not is determined, and the effect of accurately identifying whether the three-way catalyst leaks ammonia or not is achieved.

In an alternative, the method further comprises:

Step S204, under the condition that the three-way catalyst is determined not to have ammonia leakage, acquiring the number of windows which have no ammonia leakage, wherein the operation conditions of the vehicles corresponding to different windows are the same;

the same operation condition means that the vehicle is in a steady-state condition, and oxygen concentration data detected by the nitrogen oxide sensor is larger than a preset value.

Step S205 of adjusting an air-fuel ratio set value of the engine in the vehicle such that the air-fuel ratio set value after adjustment is larger than the air-fuel ratio set value before adjustment, and acquiring the oxygen concentration data after adjustment of the air-fuel ratio set value, in a case where the number of windows in which ammonia leakage does not occur is larger than or equal to a fourth threshold;

Step S206, determining at least whether ammonia leakage occurs in the three-way catalyst according to a magnitude relation between the oxygen concentration data after the air-fuel ratio setting value is adjusted and the oxygen concentration data before the air-fuel ratio setting value is adjusted.

In the embodiment, under the condition that the three-way catalyst is confirmed to not leak ammonia, the window number of the ammonia leakage which does not occur under the same operation condition is accumulated, when the window number reaches or exceeds a preset threshold value, the problem that the oxygen concentration data detected by the nitrogen oxide sensor has large fluctuation due to the aging of the three-way catalyst and the like possibly exists, so that the judgment of ammonia leakage is disturbed, at the moment, in order to further ensure the monitoring accuracy of ammonia leakage, the air-fuel ratio set value of the vehicle engine is adjusted to be increased, then the oxygen concentration data before and after the air-fuel ratio set value is compared and adjusted is used as the basis for further judging whether the three-way catalyst leaks ammonia, and the accuracy and the sensitivity of ammonia leakage identification are further improved by dynamically adjusting the air-fuel ratio and observing the oxygen concentration change.

In particular, in order to meet the technical route of the equivalence ratio plus the three-way catalyst of the natural gas engine, the air-fuel ratio needs to be controlled in a smaller window so that the nitrogen oxides, methane, carbon monoxide and ammonia can be converted with high efficiency. When the air-fuel ratio is low and deviates from the emission window, the oxygen concentration is continuously reduced, resulting in ammonia leakage. When the three-way catalyst is seriously aged, the oxygen storage capacity of the three-way catalyst is obviously reduced, the oxygen concentration measured by the nitrogen oxide sensor can be greatly fluctuated, the limiting value conditions of the steps S201, S202 and S203 can not be met, the air-fuel ratio set value is required to be actively regulated, and whether ammonia leakage occurs or not is judged according to the change of the adjusted oxygen concentration data. Wherein the equivalent ratio refers to the molar ratio of catalyst to substrate, and in a three-way catalyst, it is generally referred to as the molar ratio of nitrogen oxides to carbon monoxide. The choice of the equivalence ratio has a significant impact on the effectiveness of the catalytic reaction and it is generally desirable to determine the optimum equivalence ratio based on the particular reaction conditions and the characteristics of the catalyst.

In still other exemplary embodiments, at least determining whether or not ammonia leakage occurs in the three-way catalyst based on a magnitude relation between the oxygen concentration data after adjusting the air-fuel ratio setting value and the oxygen concentration data before adjusting the air-fuel ratio setting value includes a third determining step of determining that ammonia leakage occurs in the three-way catalyst when the oxygen concentration data after adjusting the air-fuel ratio setting value is smaller than the oxygen concentration data before adjusting the air-fuel ratio setting value, and determining that ammonia leakage does not occur in the three-way catalyst when the oxygen concentration data after adjusting the air-fuel ratio setting value is greater than or equal to the oxygen concentration data before adjusting the air-fuel ratio setting value, and an adjusting step of continuing to adjust the air-fuel ratio setting value such that a current adjustment direction of the air-fuel ratio setting value is the same as a previous adjustment direction when it is determined that ammonia leakage does not occur in the three-way catalyst, and performing the third determining step and the adjusting step in a cycle for a predetermined number of times.

In the embodiment, firstly, by comparing the oxygen concentration data before and after the air-fuel ratio setting value is adjusted, whether the three-way catalyst has ammonia leakage or not can be judged, when the adjusted oxygen concentration data is smaller than the data before adjustment, the ammonia leakage is determined, otherwise, the ammonia leakage is determined not to occur. And guiding the adjustment direction of the subsequent air-fuel ratio set value according to the judgment result of ammonia leakage. When it is determined that ammonia leakage has occurred, the same adjustment direction as the previous one is maintained, and when ammonia leakage has not occurred, the adjustment direction opposite to the previous one is adopted. Finally, through the steps of circularly executing and determining and adjusting, continuous monitoring of ammonia leakage of the three-way catalyst and dynamic adjustment of the air-fuel ratio set value are further realized, and therefore the effect of accurately identifying ammonia leakage in the three-way catalyst is further achieved.

Specifically, the adjustment direction in the current adjustment direction and the last adjustment direction refers to a direction selected when adjusting the air-fuel ratio set value, including increasing or decreasing.

In another alternative, the method for obtaining the number of windows without ammonia leakage in the case that the three-way catalyst is determined to not have ammonia leakage comprises a counting step, wherein the counting value is controlled to be increased by 1 in the case that the three-way catalyst is determined to not have ammonia leakage, and a second circulating step is performed to obtain the number of windows without ammonia leakage through the obtaining step, the first determining step, the second determining step and the counting step. In the embodiment, under the condition that the three-way catalyst is confirmed to not have ammonia leakage, the window number without ammonia leakage is counted in a cycle counting mode, so that the effect of accurately monitoring the window number without ammonia leakage is achieved.

Specifically, the initial value of the count value is 0, and the count value is reset to 0 when the number of windows is greater than or equal to a fourth threshold value.

In another alternative, adjusting the air-fuel ratio setting of the engine in the vehicle includes adjusting a fuel injector injection time of the vehicle or adjusting a throttle opening of the vehicle to adjust the air-fuel ratio setting of the engine in the vehicle.

Specifically, the fuel injector is responsible for injecting fuel into the engine cylinder, and the throttle is positioned in front of the engine intake manifold to control the amount of air entering the cylinder.

In the embodiment, the amount of fuel injected into the cylinder can be controlled by adjusting the injection time of the injector. The fuel amount increases, the air-fuel ratio decreases when the air amount remains unchanged, and the fuel amount decreases, and the air-fuel ratio increases when the air amount remains unchanged. By adjusting the opening degree of the throttle valve, the amount of air entering the cylinder can be controlled, and when the opening degree of the throttle valve increases, the amount of air entering the cylinder increases with the fuel injection amount remaining unchanged, the air-fuel ratio increases, and when the opening degree of the throttle valve decreases, the amount of air entering the cylinder decreases, with the fuel injection amount remaining unchanged, the air-fuel ratio decreases. The air-fuel ratio of the engine can be flexibly adjusted according to the needs through the adjusting mechanism.

In still other embodiments, adjusting the air-fuel ratio setting of the engine in the vehicle includes fine-tuning the air-fuel ratio setting by a predetermined step to observe changes in NOx sensor readings, using a stepwise adjustment. If the read value shows an expected change trend, the current adjusting direction and the step length are maintained, if the read value does not show an expected change or the change trend is opposite, the reverse adjustment is needed, the change of the read value of the nitrogen oxide sensor is continuously observed, and fine adjustment is carried out based on the change result of the read value until the system can accurately judge whether ammonia leakage exists.

In still further exemplary aspects of the present application, the method further includes, prior to the step of obtaining, obtaining a steady state determination parameter including at least a portion of a rotational speed of the engine, a rotational speed change rate, an intake charge of the engine, an intake charge change rate, a water temperature of the engine, a temperature of the three-way catalyst, a mass flow rate of exhaust gas in the exhaust pipe, an operating state of the nitrogen oxide sensor, and an operating state of the vehicle, determining that the vehicle is in the steady state operating condition if the steady state determination parameter satisfies a preset condition including at least a portion of the rotational speed being within a first preset range, the rotational speed change rate being within a second preset range, the intake charge being within a third preset range, the intake charge change rate being within a fourth preset range, the water temperature being within a fifth preset range, the temperature being within a sixth preset range, the mass flow rate being within a seventh preset range, the nitrogen oxide sensor being in a normal operating state, and the vehicle being in a normal operating state.

In the embodiment, whether the vehicle is in a steady-state working condition is determined according to at least part of the rotating speed, the rotating speed change rate, the air inlet charge of the engine, the air inlet charge change rate, the water temperature of the engine, the temperature of the three-way catalyst, the mass flow of tail gas in the exhaust pipe, the working state of the nitrogen oxide sensor and the working state of the vehicle, so that whether the vehicle is in the steady-state working condition can be accurately reflected, and the accurate judgment on the working state of the vehicle is ensured. Because the running parameters of the engine are relatively stable under the steady-state working condition of the vehicle, the method is beneficial to reducing the interference caused by the working condition change, so that the follow-up ammonia leakage detection step is more effectively executed, and the accuracy and reliability of the ammonia leakage detection are further improved.

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 method for detecting ammonia leakage of the three-way catalyst of the present application will be described in detail with reference to specific embodiments.

The embodiment relates to a specific method for detecting ammonia leakage of a three-way catalyst, as shown in fig. 3, comprising the following steps:

Step S1, acquiring a time duty ratio and oxygen concentration distribution of oxygen concentration data in a window, wherein the time duty ratio and the oxygen concentration distribution are smaller than a first threshold value;

step S2, judging whether the time duty ratio is larger than a second threshold value, if so, executing step S3, and if so, executing step S4;

step S3, judging whether the oxygen concentration distribution is smaller than a third threshold value, if the oxygen concentration distribution is smaller than the third threshold value, determining that ammonia leakage occurs in the three-way catalyst, and if the oxygen concentration distribution is larger than or equal to the third threshold value, executing step S4;

Step S4, under the condition that the three-way catalyst is determined not to have ammonia leakage, the control count value is increased by 1;

Step S5, judging whether the count value is larger than or equal to a fourth threshold value, if the count value is larger than or equal to the fourth threshold value, executing step S6, and if the count value is smaller than the fourth threshold value, executing at least steps S1, S2 and S3 in a circulating way;

Step S6, adjusting the air-fuel ratio set value of the engine to obtain oxygen concentration data;

And S7, judging whether the oxygen concentration data after the air-fuel ratio setting value is smaller than the oxygen concentration data before the air-fuel ratio setting value is adjusted, if the oxygen concentration data after the air-fuel ratio setting value is smaller than the oxygen concentration data before the air-fuel ratio setting value is adjusted, determining that the three-way catalyst has ammonia leakage, and if the oxygen concentration data after the air-fuel ratio setting value is greater than or equal to the oxygen concentration data before the air-fuel ratio setting value is adjusted, determining that the three-way catalyst has no ammonia leakage.

It should be noted that the steps illustrated in the flowcharts of the figures may be performed in a computer system such as a set of computer executable instructions, and that although a logical order is illustrated in the flowcharts, in some cases the steps illustrated or described may be performed in an order other than that illustrated herein.

The embodiment of the application also provides a device for detecting the ammonia leakage of the three-way catalyst, and the device for detecting the ammonia leakage of the three-way catalyst can be used for executing the method for detecting the ammonia leakage of the three-way catalyst. The device is used for implementing the embodiments and the preferred embodiments, and is not described again. As used below, the term "module" may be a combination of software and/or hardware that implements a predetermined function. While the means described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and contemplated.

The following describes a detection device for ammonia leakage of a three-way catalyst provided by an embodiment of the present application.

Fig. 4 is a schematic diagram of a detection device for ammonia slip of a three-way catalyst according to an embodiment of the present application. As shown in fig. 4, the apparatus includes:

A first obtaining unit 10, configured to obtain, when the vehicle is in a steady-state working condition and the oxygen concentration data detected by a nitrogen oxide sensor is greater than a preset value, a time duty ratio and an oxygen concentration distribution of the oxygen concentration data in a window, where the window is a preset time period or a time period required by an engine to complete a preset work, the nitrogen oxide sensor is installed in an exhaust pipe of the three-way catalyst, the oxygen concentration data is an oxygen concentration of exhaust gas in the exhaust pipe of the three-way catalyst, and the oxygen concentration distribution is a distribution of the oxygen concentration data in the window;

A first determining unit 20 for determining whether the time duty ratio is greater than a second threshold value and whether the oxygen concentration distribution is less than a third threshold value in the first determining step;

And a second determination unit 30 configured to determine that ammonia leakage occurs in the three-way catalyst in a case where the time duty ratio is greater than the second threshold value and the oxygen concentration distribution is less than the third threshold value, and determine that ammonia leakage does not occur in the three-way catalyst in a case where the time duty ratio is less than or equal to the second threshold value or the oxygen concentration distribution is greater than or equal to the third threshold value.

According to the embodiment, when the vehicle is in a steady-state working condition and the oxygen concentration data detected by the nitrogen oxide sensor is larger than a preset value, a time proportion and an oxygen concentration distribution of which the oxygen concentration data is smaller than a first threshold value in one window are obtained, whether the time proportion is larger than a second threshold value and whether the oxygen concentration distribution is smaller than a third threshold value are determined through a first determining unit, ammonia leakage of the three-way catalyst is determined through a second determining unit when the time proportion is larger than the second threshold value and the oxygen concentration distribution is smaller than the third threshold value, and ammonia leakage of the three-way catalyst is determined not when the time proportion is smaller than or equal to the second threshold value or when the oxygen concentration distribution is larger than or equal to the third threshold value. According to the application, whether the three-way catalyst leaks ammonia or not is determined according to the oxygen concentration data and the oxygen concentration distribution condition measured by the nitrogen oxide sensor in one window, so that the effect of accurately identifying whether the three-way catalyst leaks ammonia or not is achieved.

In another alternative, the apparatus further comprises:

the second acquisition unit is used for acquiring the number of windows in which ammonia leakage does not occur under the condition that the three-way catalyst is determined not to occur, and the running conditions of the vehicles corresponding to different windows are the same;

An adjusting unit configured to adjust an air-fuel ratio set value of the engine in the vehicle such that the air-fuel ratio set value after adjustment is larger than the air-fuel ratio set value before adjustment, and acquire the oxygen concentration data after adjustment of the air-fuel ratio set value, in a case where the number of windows in which ammonia leakage does not occur is larger than or equal to a fourth threshold value;

And a third determining unit configured to determine at least whether or not ammonia leakage occurs in the three-way catalyst, based on a magnitude relation between the oxygen concentration data after the air-fuel ratio setting value is adjusted and the oxygen concentration data before the air-fuel ratio setting value is adjusted.

In another alternative, the third determining unit includes:

A determining module configured to determine that ammonia leakage occurs in the three-way catalyst when the oxygen concentration data after adjustment of the air-fuel ratio setting value is smaller than the oxygen concentration data before adjustment of the air-fuel ratio setting value, and determine that ammonia leakage does not occur in the three-way catalyst when the oxygen concentration data after adjustment of the air-fuel ratio setting value is greater than or equal to the oxygen concentration data before adjustment of the air-fuel ratio setting value;

the first adjusting module is used for continuously adjusting the air-fuel ratio set value, so that the current adjusting direction of the air-fuel ratio set value is the same as the last adjusting direction under the condition that the ammonia leakage of the three-way catalyst is determined, and the current adjusting direction is opposite to the last adjusting direction under the condition that the ammonia leakage of the three-way catalyst is not determined;

and the first execution module is used for circularly executing the third determination step and the adjustment step for a preset number of times in a first circulation step.

In other exemplary embodiments, the second acquisition unit includes:

the control module is used for counting, and controlling the count value to be increased by 1 under the condition that the three-way catalyst is determined not to have ammonia leakage;

And the second execution module is used for circularly executing the acquisition step, the first determination step, the second determination step and the counting step to obtain the number of windows in which ammonia leakage does not occur.

In the embodiment, under the condition that the three-way catalyst is confirmed to not have ammonia leakage, the window number without ammonia leakage is counted in a cycle counting mode, so that the effect of accurately monitoring the window number without ammonia leakage is achieved.

In another alternative, the adjustment unit includes a second adjustment module for adjusting a fuel injector injection time of the vehicle or adjusting a throttle opening of the vehicle to adjust an air-fuel ratio setting of the engine in the vehicle.

In still other exemplary aspects of the application, the apparatus further comprises:

A third acquisition unit configured to acquire a steady-state determination parameter including at least a part of a rotation speed, a rotation speed change rate, an intake charge of the engine, an intake charge change rate, a water temperature of the engine, a temperature of the three-way catalyst, a mass flow rate of exhaust gas in the exhaust pipe, an operating state of the nitrogen oxide sensor, and an operating state of the vehicle, before the acquisition step;

And the fourth determining unit is used for determining that the vehicle is in the steady-state working condition under the condition that the steady-state judging parameter meets a preset condition, wherein the preset condition comprises at least part of the rotating speed in a first preset range, the rotating speed change rate in a second preset range, the air intake charge in a third preset range, the air intake charge change rate in a fourth preset range, the water temperature in a fifth preset range, the temperature in a sixth preset range, the mass flow in a seventh preset range, the nitrogen oxide sensor in a normal working state and the vehicle in a normal working state.

The detecting device for ammonia leakage of the three-way catalyst comprises a processor and a memory, wherein the first acquisition unit, the first determination unit, the second determination unit and the like are all stored in the memory as program units, and the processor executes the program units stored in the memory to realize corresponding functions. The modules are all located in the same processor, or the modules are respectively located in different processors in any combination.

The processor includes a kernel, and the kernel fetches the corresponding program unit from the memory. The inner core can be provided with one or more than one, and the problem that ammonia leakage in the three-way catalyst is difficult to accurately identify in the prior art is at least solved by adjusting the parameters of the inner core.

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

The embodiment of the invention provides a computer readable storage medium, which comprises a stored program, wherein when the program runs, equipment in which the computer readable storage medium is arranged is controlled to execute the method for detecting the ammonia leakage of the three-way catalyst.

Specifically, the method for detecting ammonia leakage of the three-way catalyst comprises the following steps:

The embodiment of the invention provides a processor which is used for running a program, wherein the method for detecting ammonia leakage of a three-way catalyst is executed when the program runs.

The application also provides a computer program product comprising computer instructions which when executed by a processor implement at least the following method steps:

The embodiment of the application also provides electronic equipment, which comprises one or more processors, a memory and one or more programs, wherein the one or more programs comprise a method for executing any one of the methods. The process executing program realizes at least the following steps:

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

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

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

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

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

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

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

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

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

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

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

1) According to the method for detecting the ammonia leakage of the three-way catalyst, firstly, under the condition that the vehicle is in a steady-state working condition and the oxygen concentration data detected by the nitrogen oxide sensor is larger than a preset value, the time proportion and the oxygen concentration distribution of the oxygen concentration data smaller than a first threshold value in a window are obtained, then whether the time proportion is larger than a second threshold value and whether the oxygen concentration distribution is smaller than a third threshold value are determined, under the condition that the time proportion is larger than the second threshold value and the oxygen concentration distribution is smaller than the third threshold value, the ammonia leakage of the three-way catalyst is determined, and under the condition that the time proportion is smaller than or equal to the second threshold value or the oxygen concentration distribution is larger than or equal to the third threshold value, the ammonia leakage of the three-way catalyst is determined. According to the oxygen concentration data and the oxygen concentration distribution condition measured by the nitrogen oxide sensor in one window, whether the three-way catalyst leaks ammonia or not is determined, and the effect of accurately identifying whether the three-way catalyst leaks ammonia or not is achieved.

2) According to the detecting device for ammonia leakage of the three-way catalyst, when the vehicle is in a steady-state working condition and the oxygen concentration data detected by the nitrogen oxide sensor is larger than a preset value, a time duty ratio and an oxygen concentration distribution of which the oxygen concentration data is smaller than a first threshold value in one window are obtained, whether the time duty ratio is larger than a second threshold value or not and whether the oxygen concentration distribution is smaller than a third threshold value or not are determined through the first determining unit, ammonia leakage of the three-way catalyst is determined through the second determining unit when the time duty ratio is larger than the second threshold value and the oxygen concentration distribution is smaller than the third threshold value, and ammonia leakage of the three-way catalyst is determined not to be generated when the time duty ratio is smaller than or equal to the second threshold value or the oxygen concentration distribution is larger than or equal to the third threshold value. According to the application, whether the three-way catalyst leaks ammonia or not is determined according to the oxygen concentration data and the oxygen concentration distribution condition measured by the nitrogen oxide sensor in one window, so that the effect of accurately identifying whether the three-way catalyst leaks ammonia or not is achieved.

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

Claims

1. A method for detecting ammonia leakage of a three-way catalytic converter, wherein the three-way catalytic converter is located in a vehicle, characterized in that the method comprises:

an acquisition step, in which, when the vehicle is in a steady-state operating condition and the oxygen concentration data detected by the nitrogen oxide sensor is greater than a preset value, a time proportion in which the oxygen concentration data is less than a first threshold value and an oxygen concentration distribution in a window are acquired, the window being a preset time period or a time period required for the engine to complete a preset work, the nitrogen oxide sensor being installed in the exhaust pipe of the three-way catalytic converter, the oxygen concentration data being the oxygen concentration of the exhaust gas in the exhaust pipe of the three-way catalytic converter, and the oxygen concentration distribution being the distribution of the oxygen concentration data in the window;

A first determination step is to determine whether the time proportion is greater than a second threshold, and whether the oxygen concentration distribution is less than a third threshold;

In the second determination step, when the time proportion is greater than the second threshold and the oxygen concentration distribution is less than the third threshold, it is determined that ammonia leakage occurs in the three-way catalytic converter; when the time proportion is less than or equal to the second threshold, or the oxygen concentration distribution is greater than or equal to the third threshold, it is determined that ammonia leakage does not occur in the three-way catalytic converter.

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

When it is determined that no ammonia leakage occurs in the three-way catalytic converter, the number of the windows where no ammonia leakage occurs is obtained, and the operating conditions of the vehicle corresponding to different windows are the same;

When the number of the windows where no ammonia leakage occurs is greater than or equal to a fourth threshold, adjusting an air-fuel ratio setting value of the engine in the vehicle so that the adjusted air-fuel ratio setting value is greater than the air-fuel ratio setting value before adjustment, and acquiring the oxygen concentration data after the air-fuel ratio setting value is adjusted;

At least whether ammonia slip occurs in the three-way catalyst is determined according to the magnitude relationship between the oxygen concentration data after the air-fuel ratio setting value is adjusted and the oxygen concentration data before the air-fuel ratio setting value is adjusted.

3. The method according to claim 2, characterized in that, at least determining whether ammonia leakage occurs in the three-way catalyst according to the magnitude relationship between the oxygen concentration data after adjusting the air-fuel ratio setting value and the oxygen concentration data before adjusting the air-fuel ratio setting value comprises:

A third determination step, in a case where the oxygen concentration data after adjusting the air-fuel ratio setting value is less than the oxygen concentration data before adjusting the air-fuel ratio setting value, determining that ammonia leakage occurs in the three-way catalyst, and in a case where the oxygen concentration data after adjusting the air-fuel ratio setting value is greater than or equal to the oxygen concentration data before adjusting the air-fuel ratio setting value, determining that ammonia leakage does not occur in the three-way catalyst;

an adjusting step of continuing to adjust the air-fuel ratio setting value, so that when it is determined that ammonia leakage occurs in the three-way catalyst, the current adjustment direction of the air-fuel ratio setting value is the same as the previous adjustment direction, and when it is determined that ammonia leakage does not occur in the three-way catalyst, the current adjustment direction is opposite to the previous adjustment direction;

The first loop step is to loop and execute the third determining step and the adjusting step a predetermined number of times.

4. The method according to claim 2, characterized in that, when it is determined that the three-way catalytic converter does not leak ammonia, obtaining the number of the windows where no ammonia leak occurs comprises:

A counting step, in which, when it is determined that no ammonia leakage occurs in the three-way catalytic converter, the count value is controlled to increase by 1;

The second loop step is to loop through the acquisition step, the first determination step, the second determination step and the counting step to obtain the number of the windows where no ammonia leakage occurs.

5. The method according to claim 2, characterized in that adjusting the air-fuel ratio setting value of the engine in the vehicle comprises:

The fuel injector injection time of the vehicle is adjusted or the throttle opening of the vehicle is adjusted, thereby adjusting the air-fuel ratio setting value of the engine in the vehicle.

6. The method according to any one of claims 1 to 5, characterized in that before the obtaining step, the method further comprises:

Acquire steady-state determination parameters, wherein the steady-state determination parameters include at least part of the following: the speed of the engine, the speed change rate, the intake air charge of the engine, the intake air charge change rate, the water temperature of the engine, the temperature of the three-way catalytic converter, the mass flow rate of the exhaust gas in the exhaust pipe, the working state of the nitrogen oxide sensor, and the working state of the vehicle;

When the steady-state judgment parameter meets the preset conditions, it is determined that the vehicle is in the steady-state operating condition, and the preset conditions include at least part of the following: the speed is within a first preset range, the speed change rate is within a second preset range, the intake charge is within a third preset range, the intake charge change rate is within a fourth preset range, the water temperature is within a fifth preset range, the temperature is within a sixth preset range, the mass flow rate is within a seventh preset range, the nitrogen oxide sensor is in a normal working state, and the vehicle is in a normal working state.

7. A device for detecting ammonia leakage of a three-way catalytic converter, wherein the three-way catalytic converter is located in a vehicle, characterized in that it comprises:

a first acquisition unit, configured to acquire, in a step of acquiring, when the vehicle is in a steady-state operating condition and the oxygen concentration data detected by the nitrogen oxide sensor is greater than a preset value, a time proportion in a window in which the oxygen concentration data is less than a first threshold value and an oxygen concentration distribution, wherein the window is a preset time period or a time period required for the engine to complete a preset work, the nitrogen oxide sensor is installed in the exhaust pipe of the three-way catalytic converter, the oxygen concentration data is the oxygen concentration of the exhaust gas in the exhaust pipe of the three-way catalytic converter, and the oxygen concentration distribution is the distribution of the oxygen concentration data in the window;

A first determining unit, used in a first determining step, determines whether the time proportion is greater than a second threshold, and whether the oxygen concentration distribution is less than a third threshold;

The second determination unit is used for the second determination step, to determine that ammonia leakage occurs in the three-way catalytic converter when the time proportion is greater than the second threshold and the oxygen concentration distribution is less than the third threshold; and to determine that ammonia leakage does not occur in the three-way catalytic converter when the time proportion is less than or equal to the second threshold, or the oxygen concentration distribution is greater than or equal to the third threshold.

8. A computer-readable storage medium, characterized in that the computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the method according to any one of claims 1 to 6.

9. A computer program product, comprising computer instructions, characterized in that when the computer instructions are executed by a processor, the method according to any one of claims 1 to 6 is implemented.

10. An electronic device, characterized in that it comprises: one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include a method for executing any one of claims 1 to 6.