Engine preignition identification method and device, vehicle and storage medium
By combining the change in nitrogen oxide concentration and the knock signal, and using model nitrogen oxide calculation and filtering processing, the problem of low accuracy in hydrogen engine pre-ignition identification is solved, achieving higher identification accuracy and reliability.
Patent Information
- Application Number
- CN202510846218.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-23
- Publication Date
- 2025-09-16
AI Technical Summary
The accuracy of hydrogen engine pre-ignition identification is low and misjudgment is caused by noise. The existing method relies on cylinder vibration sensors with poor accuracy.
By integrating the changes in nitrogen oxide concentration and knock signals, combined with model nitrogen oxide calculation and filtering processing, engine pre-ignition can be identified.
Improves the accuracy and reliability of pre-ignition identification, distinguishes true pre-ignition from noise interference, and prevents engine damage.
Smart Images
Figure CN120650064A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of vehicle technology, and in particular to an engine pre-ignition identification method, device, vehicle, and storage medium. Background Art
[0002] As a clean and efficient energy source, hydrogen has attracted considerable attention due to its excellent combustion performance, near-zero pollutant emissions, and renewable nature. Hydrogen engines, with their significant advantages of zero carbon emissions, high efficiency, and low cost, are gaining increasing attention.
[0003] However, hydrogen engines are prone to pre-ignition and abnormal combustion due to factors such as nozzle aging and leakage, and the presence of oil droplets. Pre-ignition not only reduces engine performance but can also cause engine damage. Traditional pre-ignition identification methods rely primarily on knock sensors mounted on the cylinder block, which detect pre-ignition by detecting cylinder vibration. For example, pre-ignition can be identified by distinguishing the increased voltage of the vibration sensor caused by cylinder vibration during pre-ignition from the low voltage when there is no pre-ignition. However, noise from hydrogen engine nozzle vibrations, valve seating, and other factors can also cause cylinder vibrations, causing the vibration sensor voltage to increase, leading to misjudgment of the knock sensor and reducing the accuracy of pre-ignition signal recognition, which urgently needs to be addressed. Summary of the Invention
[0004] The present application provides an engine pre-ignition identification method, device, vehicle and storage medium to solve the technical problem of low accuracy of pre-ignition identification due to noise in the background technology. By integrating multi-dimensional information such as changes in nitrogen oxide concentration and knock signals, the accuracy and reliability of pre-ignition identification are improved.
[0005] A first embodiment of the present application provides an engine pre-ignition identification method, comprising the following steps: Determining a change in actual nitrogen oxide concentration emitted by the current engine, and obtaining a state of a first pre-ignition identification flag according to the change in actual nitrogen oxide concentration emitted; determining a model nitrogen oxide concentration based on a preset model nitrogen oxide calculation strategy, obtaining a nitrogen oxide concentration growth coefficient based on the actual nitrogen oxide concentration emitted by the current engine and the model nitrogen oxide concentration, and obtaining a state of a second pre-ignition identification flag based on the nitrogen oxide concentration growth coefficient; Acquiring a knock energy signal value of the current engine, and obtaining a state of a third pre-ignition identification flag according to the knock energy signal value of the current engine; When the states of the first pre-ignition identification flag, the second pre-ignition identification flag, and the third pre-ignition identification flag are all in preset states, it is determined that pre-ignition occurs in the current engine.
[0006] According to one embodiment of the present application, determining a change in actual exhaust nitrogen oxide concentration of the current engine and obtaining a state of a first pre-ignition identification flag according to the change in actual exhaust nitrogen oxide concentration includes: Obtaining the actual exhaust nitrogen oxide concentration of the current engine; performing filtering processing on the actual nitrogen oxide emission concentration to obtain a filtered nitrogen oxide concentration, and obtaining a change in the actual nitrogen oxide emission concentration based on a difference between the actual nitrogen oxide emission concentration and the filtered nitrogen oxide concentration; If the change in the actual exhaust nitrogen oxide concentration is greater than a first preset threshold, the state of the first pre-ignition identification flag is set to the preset state.
[0007] According to one embodiment of the present application, determining the model nitrogen oxide concentration based on a preset model nitrogen oxide calculation strategy includes: Obtaining the current engine speed, relative air charge, excess air coefficient, and engine water temperature; querying a preset master nitrogen oxide emission table based on the current engine speed and the relative air charge to obtain a basic model value; querying a first preset correction curve based on the excess air coefficient to obtain a first correction coefficient; querying a second preset correction curve based on the engine water temperature to obtain a second correction coefficient; The product of the basic model value, the first correction coefficient, and the second correction coefficient is calculated to obtain the model nitrogen oxide concentration.
[0008] According to one embodiment of the present application, obtaining a nitrogen oxide concentration growth coefficient based on the actual nitrogen oxide concentration of the current engine and the model nitrogen oxide concentration, and obtaining a state of a second pre-ignition identification flag based on the nitrogen oxide concentration growth coefficient, includes: Obtaining the nitrogen oxide concentration growth coefficient according to a ratio between the actual nitrogen oxide concentration emitted by the current engine and the model nitrogen oxide concentration; If the nitrogen oxide concentration growth coefficient is greater than a second preset threshold, the state of the second pre-ignition identification flag is set to the preset state.
[0009] According to one embodiment of the present application, obtaining the state of the third pre-ignition identification flag according to the current engine knock energy signal value includes: determining whether the current engine knock energy signal value is greater than a third preset threshold; If the knock energy signal value of the current engine is greater than the third preset threshold, the state of the third pre-ignition identification flag is set to the preset state.
[0010] According to the engine pre-ignition identification method provided in an embodiment of the present application, the state of a first pre-ignition identification flag is determined based on the change in the actual emission nitrogen oxide concentration of the current engine; a nitrogen oxide concentration growth coefficient is determined based on the actual emission nitrogen oxide concentration and the model nitrogen oxide concentration, and the state of a second pre-ignition identification flag is then determined; and the state of a third pre-ignition identification flag is determined based on the knock energy signal value of the current engine. When the states of the first pre-ignition identification flag, the second pre-ignition identification flag, and the third pre-ignition identification flag are all in a preset state, the current engine is determined to have pre-ignition. This solves the technical problem of low pre-ignition identification accuracy due to noise in the prior art and improves the accuracy and reliability of pre-ignition identification by integrating multi-dimensional information such as nitrogen oxide concentration changes and knock signals.
[0011] A second embodiment of the present application provides an engine pre-ignition identification device, comprising: a first processing module, configured to determine a change in actual nitrogen oxide concentration emitted by the current engine, and obtain a state of a first pre-ignition identification flag according to the change in actual nitrogen oxide concentration emitted; a second processing module, configured to determine a model nitrogen oxide concentration based on a preset model nitrogen oxide calculation strategy, obtain a nitrogen oxide concentration growth coefficient based on the actual nitrogen oxide concentration emitted by the current engine and the model nitrogen oxide concentration, and obtain a state of a second pre-ignition identification flag based on the nitrogen oxide concentration growth coefficient; a third processing module, configured to obtain a knock energy signal value of the current engine, and obtain a state of a third pre-ignition identification flag according to the knock energy signal value of the current engine; The identification module is configured to determine that pre-ignition occurs in the current engine when the state of the first pre-ignition identification flag, the state of the second pre-ignition identification flag, and the state of the third pre-ignition identification flag are all in a preset state.
[0012] According to one embodiment of the present application, the first processing module is configured to: Obtaining the actual exhaust nitrogen oxide concentration of the current engine; performing filtering processing on the actual nitrogen oxide emission concentration to obtain a filtered nitrogen oxide concentration, and obtaining a change in the actual nitrogen oxide emission concentration based on a difference between the actual nitrogen oxide emission concentration and the filtered nitrogen oxide concentration; If the change in the actual exhaust nitrogen oxide concentration is greater than a first preset threshold, the state of the first pre-ignition identification flag is set to the preset state.
[0013] According to one embodiment of the present application, the second processing module is configured to: Obtaining the current engine speed, relative air charge, excess air coefficient, and engine water temperature; querying a preset master nitrogen oxide emission table based on the current engine speed and the relative air charge to obtain a basic model value; querying a first preset correction curve based on the excess air coefficient to obtain a first correction coefficient; querying a second preset correction curve based on the engine water temperature to obtain a second correction coefficient; The product of the basic model value, the first correction coefficient, and the second correction coefficient is calculated to obtain the model nitrogen oxide concentration.
[0014] According to one embodiment of the present application, the second processing module is configured to: Obtaining the nitrogen oxide concentration growth coefficient according to a ratio between the actual nitrogen oxide concentration emitted by the current engine and the model nitrogen oxide concentration; If the nitrogen oxide concentration growth coefficient is greater than a second preset threshold, the state of the second pre-ignition identification flag is set to the preset state.
[0015] According to one embodiment of the present application, the third processing module is configured to: determining whether the current engine knock energy signal value is greater than a third preset threshold; If the knock energy signal value of the current engine is greater than the third preset threshold, the state of the third pre-ignition identification flag is set to the preset state.
[0016] According to the engine pre-ignition identification device provided in an embodiment of the present application, the state of a first pre-ignition identification flag is determined based on the change in the actual emission nitrogen oxide concentration of the current engine; a nitrogen oxide concentration growth coefficient is determined based on the actual emission nitrogen oxide concentration and the model nitrogen oxide concentration, and the state of a second pre-ignition identification flag is then determined; and the state of a third pre-ignition identification flag is determined based on the knock energy signal value of the current engine. When the states of the first pre-ignition identification flag, the second pre-ignition identification flag, and the third pre-ignition identification flag are all in a preset state, the current engine is determined to have pre-ignition. This solves the technical problem of low pre-ignition identification accuracy due to noise in the prior art, and improves the accuracy and reliability of pre-ignition identification by integrating multi-dimensional information such as nitrogen oxide concentration changes and knock signals.
[0017] The third aspect of the present application provides a vehicle, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the engine pre-ignition identification method as described in the above embodiment.
[0018] A fourth aspect of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable the computer to execute the engine pre-ignition identification method as described in the above embodiment.
[0019] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which: Figure 1 This is a flow chart of a method for identifying engine pre-ignition according to an embodiment of the present application; Figure 2 A logic diagram for identifying pre-ignition for actual exhaust nitrogen oxide changes according to one embodiment of the present application; Figure 3 A logic diagram for identifying pre-ignition by comparing actual NOx emissions with model NOx emissions according to one embodiment of the present application; Figure 4 A logic diagram for identifying pre-ignition from a knock signal according to one embodiment of the present application; Figure 5 A logic diagram for comprehensively identifying pre-ignition according to one embodiment of the present application; Figure 6 Schematic diagram of a block diagram of an engine pre-ignition identification device according to an embodiment of the present application; Figure 7 A schematic diagram of the structure of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION
[0021] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.
[0022] Those skilled in the art will understand that when pre-ignition occurs in a hydrogen engine, the accompanying rapid increase in in-cylinder explosion pressure leads to a sudden increase in nitrogen oxides (NOx) in the engine's exhaust emissions. To reduce NOx concentrations in lean-burn exhaust, hydrogen engines are typically equipped with selective catalytic reduction (SCR) technology. SCR technology requires a NOx concentration sensor in the engine exhaust to monitor NOx concentrations in real time and calculate the amount of urea injected. A NOx concentration sensor in the exhaust system facilitates pre-ignition detection.
[0023] The following describes an engine pre-ignition identification method, device, vehicle, and storage medium according to an embodiment of the present application with reference to the accompanying drawings. In response to the problem of low pre-ignition identification accuracy due to noise as mentioned in the background art, the present application utilizes the principle that pre-ignition in a hydrogen engine causes an increase in nitrogen oxide emissions, and proposes an engine pre-ignition identification method. In this method, the phenomenon of increased nitrogen oxide emissions caused by increased explosion pressure during pre-ignition in a hydrogen engine is combined with the identification and processing of nitrogen oxide signals to identify the occurrence of engine pre-ignition. Furthermore, the method, combined with the engine's own knock sensor, can identify the cylinder number where pre-ignition occurred, thereby identifying problems such as nozzle aging and cylinder abnormalities in advance, preventing engine damage, and improving the problem of noise such as nozzle vibration and valve seating in hydrogen engines affecting pre-ignition signal identification.
[0024] Specifically, Figure 1 A flow chart of an engine pre-ignition identification method provided in an embodiment of the present application.
[0025] like Figure 1 As shown, the engine pre-ignition identification method includes the following steps: In step S101, the actual change in the concentration of nitrogen oxides emitted by the current engine is determined, and the state of the first pre-ignition identification flag is obtained according to the actual change in the concentration of nitrogen oxides emitted.
[0026] Furthermore, in some embodiments, the change in the actual emission nitrogen oxide concentration in the current engine exhaust is determined, and the state of the first pre-ignition identification flag is obtained based on the change in the actual emission nitrogen oxide concentration, including: obtaining the actual emission nitrogen oxide concentration of the current engine; filtering the actual emission nitrogen oxide concentration to obtain the filtered nitrogen oxide concentration, and obtaining the change in the actual emission nitrogen oxide concentration based on the difference between the actual emission nitrogen oxide concentration and the filtered nitrogen oxide concentration; if the change in the actual emission nitrogen oxide concentration is greater than a first preset threshold value, the state of the first pre-ignition identification flag is set to a preset state.
[0027] Optionally, the embodiment of the present application can obtain the actual emission nitrogen oxide concentration of the current engine through a nitrogen oxide concentration sensor set in the engine exhaust, which is not specifically limited here.
[0028] Specifically, if Figure 2 As shown, the present embodiment identifies pre-ignition by identifying changes in the actual nitrogen oxide concentration ActNOX. First, the actual nitrogen oxide concentration ActNOX is filtered through a filter to obtain a filtered nitrogen oxide concentration FilNOX. The difference between the actual nitrogen oxide concentration ActNOX and the filtered nitrogen oxide concentration FilNOX is then calculated to obtain the actual nitrogen oxide concentration change DeNOX. If the actual nitrogen oxide concentration ActNOX suddenly increases due to pre-ignition, the actual nitrogen oxide concentration change DeNOX will suddenly increase to a larger value. Figure 2 PREIGN1_MAP is a table of nitrogen oxide concentration thresholds calibrated based on engine speed and relative charge volume (rl), output as Limitpreig1. When the actual change in nitrogen oxide concentration (DeNOX) exceeds the threshold (Limitpreig1), the pre-ignition identification flag (B_preig1) is set to 1.
[0029] In step S102, based on the preset model nitrogen oxide calculation strategy, the model nitrogen oxide concentration is determined, and the nitrogen oxide concentration growth coefficient is obtained according to the actual emission nitrogen oxide concentration of the current engine and the model nitrogen oxide concentration, and the state of the second pre-ignition identification flag is obtained according to the nitrogen oxide concentration growth coefficient.
[0030] Furthermore, in some embodiments, the model nitrogen oxide concentration is determined based on a preset model nitrogen oxide calculation strategy, including: obtaining the current engine speed, relative air charge, excess air coefficient and engine water temperature; querying a preset main nitrogen oxide emission table based on the current engine speed and relative air charge to obtain a basic model value; querying a first preset correction curve based on the excess air coefficient to obtain a first correction coefficient; querying a second preset correction curve based on the engine water temperature to obtain a second correction coefficient; and calculating the product of the basic model value, the first correction coefficient and the second correction coefficient to obtain the model nitrogen oxide concentration.
[0031] Among them, the preset main nitrogen oxide emission table is calibrated by the engine speed speed and the relative air charge rl, the first preset correction curve is calibrated by the excess air coefficient, and the second preset correction curve is calibrated by the engine water temperature.
[0032] Optionally, the embodiment of the present application can obtain the current engine speed through a speed sensor, calculate the relative charging volume based on data such as the air mass flow, engine speed, and engine displacement under the current operating conditions of the engine, determine the excess air coefficient through flue gas analysis calculations, and obtain the current engine water temperature through a temperature sensor, which is not specifically limited here.
[0033] Specifically, if Figure 3 As shown, the present embodiment identifies pre-ignition by comparing actual NOx emissions from a hydrogen engine with modeled NOx emissions. First, based on the current engine speed and relative air charge, a master NOx emissions table, ModNox_MAP, calibrated based on speed and relative air charge, is queried to obtain a base model value. Based on the excess air coefficient, a correction curve, FacLam_CUR, calibrated based on excess air coefficient lam, is queried to obtain a first correction coefficient. Based on the engine water temperature, a correction curve, FacTwo_CUR, calibrated based on engine water temperature two, is queried to obtain a second correction coefficient.
[0034] Furthermore, a model nitrogen oxide concentration ModNOX is calculated based on the basic model value, the first correction coefficient, and the second correction coefficient. The model nitrogen oxide concentration ModNOX is obtained by multiplying the basic model value, the first correction coefficient, and the second correction coefficient.
[0035] Furthermore, in some embodiments, a nitrogen oxide concentration growth coefficient is obtained based on the actual nitrogen oxide concentration emitted by the current engine and the model nitrogen oxide concentration, and the state of the second pre-ignition identification flag is obtained based on the nitrogen oxide concentration growth coefficient, including: obtaining the nitrogen oxide concentration growth coefficient based on the ratio between the actual nitrogen oxide concentration emitted by the current engine and the model nitrogen oxide concentration; if the nitrogen oxide concentration growth coefficient is greater than a second preset threshold value, the state of the second pre-ignition identification flag is set to a preset state.
[0036] Specifically, if Figure 3 As shown in the figure, the ratio between the actual NOx concentration ActNOX and the model NOx concentration ModNOX is calculated to obtain the NOx concentration growth coefficient FacNox. When pre-ignition occurs, the actual NOx concentration ActNOX increases. The actual NOx concentration is greater than the model NOx concentration ModNOX, and the NOx concentration growth coefficient FacNox increases.
[0037] Furthermore, Figure 3PREIGN2_MAP is a table of nitrogen oxide growth factor thresholds calibrated based on engine speed and relative air charge (rl), output as Limitpreig2. When the growth factor FacNox of the actual nitrogen oxide concentration ActNOX relative to the model nitrogen oxide concentration ModNOX exceeds the threshold Limitpreig2, the pre-ignition identification flag B_preig2 (the second pre-ignition identification flag) is set to 1.
[0038] In step S103, the knock energy signal value of the current engine is obtained, and the state of the third pre-ignition identification flag is obtained according to the knock energy signal value of the current engine.
[0039] Furthermore, in some embodiments, the state of the third pre-ignition identification flag is obtained based on the knock energy signal value of the current engine, including: determining whether the knock energy signal value of the current engine is greater than a third preset threshold; if the knock energy signal value of the current engine is greater than the third preset threshold, setting the state of the third pre-ignition identification flag to a preset state.
[0040] The third preset threshold may be a pre-ignition energy threshold preset by those skilled in the art, which is not specifically limited here.
[0041] Optionally, the embodiment of the present application can obtain the knock energy signal value of the current engine through a knock sensor installed on the engine cylinder block, which is not specifically limited here.
[0042] Specifically, if Figure 4 As shown, the embodiment of the present application compares the knock energy signal value KNK of the current engine with the pre-ignition energy threshold knklimit. When the knock signal energy value KNK is greater than the pre-ignition energy threshold knklimit, the output pre-ignition identification flag B_preig3 (i.e., the third pre-ignition identification flag) is set to 1.
[0043] In step S104, when the states of the first pre-ignition identification flag, the second pre-ignition identification flag, and the third pre-ignition identification flag are all in the preset states, it is determined that pre-ignition occurs in the current engine.
[0044] The preset state may be that the pre-ignition identification flag is at 1, which is not specifically limited here.
[0045] Specifically, if Figure 5As shown, the embodiment of the present application performs a logical AND operation on the first pre-ignition identification flag B_preig1, the second pre-ignition identification flag B_preig2, and the third pre-ignition identification flag B_preig3. When the first pre-ignition identification flag B_preig1, the second pre-ignition identification flag B_preig2, and the third pre-ignition identification flag B_preig3 are all set to 1, the comprehensive pre-ignition identification flag B_preig is set to 1, indicating that pre-ignition has occurred in the current engine.
[0046] Therefore, the engine pre-ignition identification method according to the embodiment of the present application can effectively distinguish abnormal judgments caused by abnormal vibrations such as hydrogen nozzles and valve seating, thereby improving the accuracy of identifying true pre-ignition.
[0047] Furthermore, if the cumulative rate of pre-ignition counts in one or more cylinders of a hydrogen engine is significantly higher than normal (e.g., more than 4 times per 200 engine combustion cycles), the hydrogen nozzle can be identified as abnormal or aged, and a message indicating the need for nozzle inspection or replacement can be output. By utilizing the increased cumulative rate of pre-ignition counts in a hydrogen engine to output information about nozzle inspection, maintenance, and replacement, the system can effectively prevent damage to hydrogen engines caused by abnormal combustion.
[0048] According to the engine pre-ignition identification method proposed in the embodiment of the present application, the state of the first pre-ignition identification flag is determined based on the change in the actual emission nitrogen oxide concentration of the current engine; the nitrogen oxide concentration growth coefficient is determined based on the actual emission nitrogen oxide concentration and the model nitrogen oxide concentration, and the state of the second pre-ignition identification flag is then determined; the state of the third pre-ignition identification flag is determined based on the knock energy signal value of the current engine; and when the states of the first pre-ignition identification flag, the second pre-ignition identification flag, and the third pre-ignition identification flag are all in preset states, it is determined that the current engine has pre-ignition. This solves the technical problem of low pre-ignition identification accuracy due to noise in the background art, and improves the accuracy and reliability of pre-ignition identification by integrating multi-dimensional information such as nitrogen oxide concentration changes and knock signals.
[0049] Next, the engine pre-ignition identification device proposed according to the embodiment of the present application is described with reference to the accompanying drawings.
[0050] Figure 6 4 is a block diagram of an engine pre-ignition identification device according to an embodiment of the present application.
[0051] like Figure 6 As shown, the engine pre-ignition identification device 10 includes: a first processing module 100 , a second processing module 200 , a third processing module 300 and an identification module 400 .
[0052] Among them, the first processing module 100 is used to determine the change in the actual emission nitrogen oxide concentration of the current engine, and obtain the state of the first pre-ignition identification flag according to the change in the actual emission nitrogen oxide concentration; the second processing module 200 is used to determine the model nitrogen oxide concentration based on the preset model nitrogen oxide calculation strategy, and obtain the nitrogen oxide concentration growth coefficient according to the actual emission nitrogen oxide concentration and the model nitrogen oxide concentration of the current engine, and obtain the state of the second pre-ignition identification flag according to the nitrogen oxide concentration growth coefficient; the third processing module 300 is used to obtain the knock energy signal value of the current engine, and obtain the state of the third pre-ignition identification flag according to the knock energy signal value of the current engine; the identification module 400 is used to determine that pre-ignition occurs in the current engine when the state of the first pre-ignition identification flag, the state of the second pre-ignition identification flag and the state of the third pre-ignition identification flag are all in the preset state.
[0053] Furthermore, in some embodiments, the first processing module 100 is used to: obtain the actual emission nitrogen oxide concentration of the current engine; filter the actual emission nitrogen oxide concentration to obtain the filtered nitrogen oxide concentration, and obtain the change in the actual emission nitrogen oxide concentration based on the difference between the actual emission nitrogen oxide concentration and the filtered nitrogen oxide concentration; if the change in the actual emission nitrogen oxide concentration is greater than a first preset threshold value, set the state of the first pre-ignition identification flag to a preset state.
[0054] Furthermore, in some embodiments, the second processing module 200 is used to: obtain the current engine speed, relative air charge, excess air coefficient and engine water temperature; query the preset main nitrogen oxide emission table based on the current engine speed and relative air charge to obtain a basic model value; query the first preset correction curve based on the excess air coefficient to obtain a first correction coefficient; query the second preset correction curve based on the engine water temperature to obtain a second correction coefficient; calculate the product of the basic model value, the first correction coefficient and the second correction coefficient to obtain a model nitrogen oxide concentration.
[0055] Furthermore, in some embodiments, the second processing module 200 is used to: obtain a nitrogen oxide concentration growth coefficient based on the ratio between the actual emission nitrogen oxide concentration of the current engine and the model nitrogen oxide concentration; if the nitrogen oxide concentration growth coefficient is greater than a second preset threshold, the state of the second pre-ignition identification flag is set to a preset state.
[0056] Furthermore, in some embodiments, the third processing module is used to: determine whether the knock energy signal value of the current engine is greater than a third preset threshold; if the knock energy signal value of the current engine is greater than the third preset threshold, set the state of the third pre-ignition identification flag to a preset state.
[0057] It should be noted that the aforementioned explanation of the embodiment of the engine pre-ignition identification method is also applicable to the engine pre-ignition identification device of this embodiment, and will not be repeated here.
[0058] According to the engine pre-ignition identification device proposed in the embodiment of the present application, the state of the first pre-ignition identification flag is determined based on the change in the actual emission nitrogen oxide concentration of the current engine; the nitrogen oxide concentration growth coefficient is determined based on the actual emission nitrogen oxide concentration and the model nitrogen oxide concentration, and the state of the second pre-ignition identification flag is then determined; the state of the third pre-ignition identification flag is determined based on the knock energy signal value of the current engine; and when the states of the first pre-ignition identification flag, the second pre-ignition identification flag, and the third pre-ignition identification flag are all in preset states, the current engine is determined to have pre-ignition. This solves the technical problem of low pre-ignition identification accuracy due to noise in the background art, and improves the accuracy and reliability of pre-ignition identification by integrating multi-dimensional information such as nitrogen oxide concentration changes and knock signals.
[0059] Figure 7 A schematic diagram of the structure of a vehicle provided in an embodiment of the present application. The vehicle may include: Memory 701 , processor 702 , and computer programs stored in the memory 701 and executable on the processor 702 .
[0060] When the processor 702 executes the program, the engine pre-ignition identification method provided in the above embodiment is implemented.
[0061] Furthermore, the vehicle further comprises: The communication interface 703 is used for communication between the memory 701 and the processor 702 .
[0062] The memory 701 is used to store computer programs that can be run on the processor 702 .
[0063] The memory 701 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.
[0064] If the memory 701, processor 702, and communication interface 703 are implemented independently, the communication interface 703, memory 701, and processor 702 can be interconnected via a bus to communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. Buses can be divided into address buses, data buses, control buses, etc. For ease of representation, Figure 7 Only one thick line is used in the diagram, but this does not mean that there is only one bus or one type of bus.
[0065] Optionally, in a specific implementation, if the memory 701, the processor 702 and the communication interface 703 are integrated on a chip, the memory 701, the processor 702 and the communication interface 703 can communicate with each other through an internal interface.
[0066] The processor 702 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.
[0067] An embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned engine pre-ignition identification method.
[0068] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.
[0069] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this application, "N" means at least two, for example, two, three, etc., unless otherwise specifically defined.
[0070] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present application belong.
[0071] The logic and / or steps represented in a flowchart or otherwise described herein, for example, can be considered a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (e.g., a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device). For purposes of this specification, a "computer-readable medium" is any device that can contain, store, communicate, propagate, or transport a program for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (not exhaustive) of computer-readable media include: an electrical connection with one or more wires (electronic devices), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and a portable compact disc read-only memory (CDROM). Furthermore, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing it in another suitable manner if necessary, and then storing it in a computer memory.
[0072] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiment, the N steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having logic gate circuits for implementing logical functions on data signals, an application-specific integrated circuit having suitable combinational logic gate circuits, a programmable gate array (PGA), a field-programmable gate array (FPGA), etc.
[0073] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.
[0074] In addition, the functional units in the various embodiments of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into a module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.
[0075] The storage medium mentioned above may be a read-only memory, a magnetic disk, or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present application. Persons skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.
Claims
1. A method for identifying engine pre-ignition, characterized in that: The following steps are involved: Determining a change in actual nitrogen oxide concentration emitted by the current engine, and obtaining a state of a first pre-ignition identification flag according to the change in actual nitrogen oxide concentration emitted; determining a model nitrogen oxide concentration based on a preset model nitrogen oxide calculation strategy, obtaining a nitrogen oxide concentration growth coefficient based on the actual nitrogen oxide concentration emitted by the current engine and the model nitrogen oxide concentration, and obtaining a state of a second pre-ignition identification flag based on the nitrogen oxide concentration growth coefficient; Acquiring a knock energy signal value of the current engine, and obtaining a state of a third pre-ignition identification flag according to the knock energy signal value of the current engine; When the states of the first pre-ignition identification flag, the second pre-ignition identification flag, and the third pre-ignition identification flag are all in preset states, it is determined that pre-ignition occurs in the current engine.
2. The method according to claim 1, characterized in that The determining of the change in actual exhaust nitrogen oxide concentration of the current engine and obtaining the state of the first pre-ignition identification flag according to the change in actual exhaust nitrogen oxide concentration includes: Obtaining the actual exhaust nitrogen oxide concentration of the current engine; performing filtering processing on the actual nitrogen oxide emission concentration to obtain a filtered nitrogen oxide concentration, and obtaining a change in the actual nitrogen oxide emission concentration based on a difference between the actual nitrogen oxide emission concentration and the filtered nitrogen oxide concentration; If the change in the actual exhaust nitrogen oxide concentration is greater than a first preset threshold, the state of the first pre-ignition identification flag is set to the preset state.
3. The method according to claim 2, characterized in that The method of determining the model nitrogen oxide concentration based on a preset model nitrogen oxide calculation strategy includes: Obtaining the current engine speed, relative air charge, excess air coefficient, and engine water temperature; querying a preset master nitrogen oxide emission table based on the current engine speed and the relative air charge to obtain a basic model value; querying a first preset correction curve based on the excess air coefficient to obtain a first correction coefficient; querying a second preset correction curve based on the engine water temperature to obtain a second correction coefficient; The product of the basic model value, the first correction coefficient, and the second correction coefficient is calculated to obtain the model nitrogen oxide concentration.
4. The method according to claim 3, characterized in that The step of obtaining a nitrogen oxide concentration growth coefficient based on the actual nitrogen oxide concentration emitted by the current engine and the model nitrogen oxide concentration, and obtaining a state of a second pre-ignition identification flag based on the nitrogen oxide concentration growth coefficient, includes: Obtaining the nitrogen oxide concentration growth coefficient according to a ratio between the actual nitrogen oxide concentration emitted by the current engine and the model nitrogen oxide concentration; If the nitrogen oxide concentration growth coefficient is greater than a second preset threshold, the state of the second pre-ignition identification flag is set to the preset state.
5. The method according to claim 1, characterized in that The state of the third pre-ignition identification flag is obtained according to the knock energy signal value of the current engine, including: determining whether the current engine knock energy signal value is greater than a third preset threshold; If the knock energy signal value of the current engine is greater than the third preset threshold, the state of the third pre-ignition identification flag is set to the preset state.
6. An engine pre-ignition identification device, characterized in that: include: a first processing module, configured to determine a change in actual nitrogen oxide concentration emitted by the current engine, and obtain a state of a first pre-ignition identification flag according to the change in actual nitrogen oxide concentration emitted; a second processing module, configured to determine a model nitrogen oxide concentration based on a preset model nitrogen oxide calculation strategy, obtain a nitrogen oxide concentration growth coefficient based on the actual nitrogen oxide concentration emitted by the current engine and the model nitrogen oxide concentration, and obtain a state of a second pre-ignition identification flag based on the nitrogen oxide concentration growth coefficient; a third processing module, configured to obtain a knock energy signal value of the current engine, and obtain a state of a third pre-ignition identification flag according to the knock energy signal value of the current engine; The identification module is configured to determine that pre-ignition occurs in the current engine when the state of the first pre-ignition identification flag, the state of the second pre-ignition identification flag, and the state of the third pre-ignition identification flag are all in a preset state.
7. The device according to claim 6, characterized in that The first processing module is configured to: Obtaining the actual exhaust nitrogen oxide concentration of the current engine; performing filtering processing on the actual nitrogen oxide emission concentration to obtain a filtered nitrogen oxide concentration, and obtaining a change in the actual nitrogen oxide emission concentration based on a difference between the actual nitrogen oxide emission concentration and the filtered nitrogen oxide concentration; If the change in the actual exhaust nitrogen oxide concentration is greater than a first preset threshold, the state of the first pre-ignition identification flag is set to the preset state.
8. The device according to claim 7, characterized in that The second processing module is configured to: Obtaining the current engine speed, relative air charge, excess air coefficient, and engine water temperature; querying a preset master nitrogen oxide emission table based on the current engine speed and the relative air charge to obtain a basic model value; querying a first preset correction curve based on the excess air coefficient to obtain a first correction coefficient; querying a second preset correction curve based on the engine water temperature to obtain a second correction coefficient; The product of the basic model value, the first correction coefficient, and the second correction coefficient is calculated to obtain the model nitrogen oxide concentration.
9. A vehicle, characterized in that: include: 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 engine pre-ignition identification method according to any one of claims 1 to 5.
10. A computer-readable storage medium having a computer program stored thereon, characterized in that: The computer program is executed by a processor to implement the engine pre-ignition identification method according to any one of claims 1 to 5.