Vehicle fault determination method and device, vehicle and storage medium

Abstract

The application discloses a vehicle fault determination method and device, a vehicle and a storage medium. The vehicle fault determination method comprises the following steps: acquiring a plurality of oil tank pressure values of the vehicle; classifying the plurality of oil tank pressure values to obtain a plurality of groups of oil tank pressure values, wherein the frequency of each group of oil tank pressure values is the same; performing Fourier transform processing on the plurality of groups of oil tank pressure values to obtain a plurality of pressure amplitudes, wherein each group of oil tank pressure values corresponds to one pressure amplitude; and determining the fault condition of the vehicle based on the plurality of pressure amplitudes. The application solves the technical problem of low accuracy of fault diagnosis of vehicle low-load desorption flow in the prior art.

Description

Technical Field

[0001] This invention relates to the field of automation control technology, and more specifically, to a method, apparatus, vehicle, and storage medium for determining vehicle faults. Background Technology

[0002] In existing technologies, vehicles are generally equipped with activated carbon canister adsorption systems to prevent hydrocarbon vapors volatilized from the fuel tank from being directly released into the atmosphere. When the engine is running, the fuel vapors adsorbed in the canister are drawn into the engine for combustion through the negative pressure in the intake manifold; this process is called "desorption." To ensure emissions compliance, the on-board automatic diagnostic system must effectively monitor the desorption flow rate to determine whether there are faults such as blockages or leaks in the pipeline.

[0003] With increasingly stringent emission regulations, higher demands are being placed on the frequency and accuracy of desorption system monitoring. This is particularly true under low-load conditions, where the desorption flow rate is low, posing challenges to the sensitivity and robustness of fault diagnosis. An ideal diagnostic strategy should utilize existing sensors to achieve high-precision, high-frequency fault identification without affecting vehicle driving performance, while effectively suppressing noise interference and meeting stringent requirements for minimum in-use monitoring frequency.

[0004] Currently, most mainstream desorption flow diagnostic solutions employ an active diagnostic approach. This involves the engine's electronic control system actively controlling the charcoal canister solenoid valve to operate fully open or closed under specific conditions, determining the presence of flow based on pressure sensor readings. This method has significant drawbacks: First, the active excitation process can disrupt engine stability, especially at low speeds or idle, potentially causing vehicle surging and affecting driving smoothness. Second, when relying on a fuel tank pressure sensor, the signal is susceptible to interference from fuel level fluctuations and high-frequency noise, leading to false alarms or missed alarms. Third, tightening the threshold to improve diagnostic accuracy often results in a decrease in the actual monitoring frequency, making it difficult to meet testing requirements.

[0005] There is currently no effective solution to the above-mentioned technical problems. Summary of the Invention

[0006] This invention provides a method, apparatus, vehicle, and storage medium for determining vehicle faults, in order to at least solve the technical problem of low accuracy in fault diagnosis of low-load desorption flow in vehicles in the prior art.

[0007] According to one embodiment of the present invention, a method for determining vehicle faults is provided, comprising: acquiring multiple fuel tank pressure values ​​of a vehicle; classifying the multiple fuel tank pressure values ​​to obtain multiple groups of fuel tank pressure values, wherein each group of fuel tank pressure values ​​has the same frequency; performing Fourier transform processing on the multiple groups of fuel tank pressure values ​​to obtain multiple pressure amplitudes, wherein each group of fuel tank pressure values ​​corresponds to one pressure amplitude; and determining the fault condition of the vehicle based on the multiple pressure amplitudes.

[0008] Optionally, the method for determining vehicle faults further includes: acquiring fault information of multiple vehicle components, including a canister solenoid valve, an air flow meter, an intake manifold pressure sensor, and an ambient pressure sensor; and acquiring multiple fuel tank pressure values ​​of the vehicle in response to the absence of electrical faults in the multiple vehicle components.

[0009] Optionally, the method for determining vehicle faults further includes: in response to the vehicle's engine being in an idling state, obtaining the duty cycle of the charcoal canister solenoid valve; comparing the duty cycle of the charcoal canister solenoid valve with a duty cycle threshold to obtain a first comparison result; in response to the first comparison result indicating that the duty cycle is greater than the duty cycle threshold, obtaining a duration segment of the duty cycle; comparing the duration segment with a preset time period to obtain a second comparison result; in response to the second comparison result indicating that the duration segment is greater than the preset time period, obtaining multiple fuel tank pressure values.

[0010] Optionally, the method for determining vehicle faults further includes: converting multiple sets of tank pressure values ​​into multiple sets of tank pressure signals; removing the DC component from the multiple sets of tank pressure signals to obtain multiple sets of pressure signals to be processed; windowing the multiple sets of pressure signals to be processed to obtain multiple sets of target pressure signals; and performing Fourier transform processing on the multiple sets of target pressure signals to obtain multiple pressure amplitudes.

[0011] Optionally, the method for determining vehicle faults further includes: comparing multiple pressure amplitudes with amplitude thresholds respectively to obtain a third comparison result; in response to the third comparison result indicating that any pressure amplitude among the multiple pressure amplitudes is greater than the amplitude threshold, determining that the vehicle does not have a low-load desorption flow fault; in response to the third comparison result indicating that all multiple pressure amplitudes are less than or equal to the amplitude threshold, determining that the vehicle has a low-load desorption flow fault.

[0012] Optionally, the method for determining vehicle faults further includes: updating the in-use monitoring frequency of low-load desorption flow in response to a fault diagnosis of the vehicle completing low-load desorption flow.

[0013] According to one embodiment of the present invention, a vehicle fault determination device is also provided, comprising: a first acquisition module for acquiring multiple fuel tank pressure values ​​of a vehicle; a classification module for classifying the multiple fuel tank pressure values ​​to obtain multiple sets of fuel tank pressure values, wherein each set of fuel tank pressure values ​​has the same frequency; a processing module for performing Fourier transform processing on the multiple sets of fuel tank pressure values ​​to obtain multiple pressure amplitudes, wherein each set of fuel tank pressure values ​​corresponds to one pressure amplitude; and a determination module for determining the vehicle fault condition based on the multiple pressure amplitudes.

[0014] Optionally, the vehicle fault determination device further includes: a second acquisition module for acquiring fault conditions of multiple vehicle components, wherein the multiple vehicle components include a charcoal canister solenoid valve, an air flow meter, an intake manifold pressure sensor, and an ambient pressure sensor; and a third acquisition module for acquiring multiple fuel tank pressure values ​​of the vehicle in response to the absence of electrical faults in the multiple vehicle components.

[0015] Optionally, the vehicle fault determination device further includes: a fourth acquisition module, used to acquire the duty cycle of the charcoal canister solenoid valve in response to the vehicle's engine being in an idling state; a first comparison module, used to compare the duty cycle of the charcoal canister solenoid valve with a duty cycle threshold to obtain a first comparison result; a fifth acquisition module, used to acquire the duration of the duty cycle in response to the first comparison result indicating that the duty cycle is greater than the duty cycle threshold; a second comparison module, used to compare the duration with a preset time period to obtain a second comparison result; and a sixth acquisition module, used to acquire multiple fuel tank pressure values ​​in response to the second comparison result indicating that the duration is greater than the preset time period.

[0016] Optionally, the processing module includes: a conversion unit for converting multiple sets of tank pressure values ​​into multiple sets of tank pressure signals; a first operation unit for removing the DC component from the multiple sets of tank pressure signals to obtain multiple sets of pressure signals to be processed; a second operation unit for windowing the multiple sets of pressure signals to be processed to obtain multiple sets of target pressure signals; and a processing unit for performing Fourier transform processing on the multiple sets of target pressure signals to obtain multiple pressure amplitudes.

[0017] Optionally, the determining module includes: a comparison unit for comparing multiple pressure amplitudes with amplitude thresholds respectively to obtain a third comparison result; a first determining unit for determining that the vehicle does not have a low-load desorption flow fault in response to the third comparison result indicating that any pressure amplitude among the multiple pressure amplitudes is greater than the amplitude threshold; and a second determining unit for determining that the vehicle has a low-load desorption flow fault in response to the third comparison result indicating that all multiple pressure amplitudes are less than or equal to the amplitude threshold.

[0018] Optionally, the vehicle fault determination device further includes an update module for updating the in-use monitoring frequency of the low-load desorption flow in response to a fault diagnosis of the vehicle completing the low-load desorption flow.

[0019] According to one embodiment of the present invention, a vehicle is also provided, including a memory and a processor, wherein the memory stores a computer program and the processor is configured to run the computer program to perform the vehicle fault determination method of any of the above claims.

[0020] According to one embodiment of the present invention, an electronic device is also provided, including a memory and a processor, wherein the memory stores a computer program and the processor is configured to run the computer program to perform the vehicle fault determination method of any of the above claims.

[0021] According to one embodiment of the present invention, a non-volatile storage medium is also provided, wherein a computer program is stored in the non-volatile storage medium, wherein the computer program is configured to execute the vehicle fault determination method described in any of the above-mentioned embodiments when running.

[0022] According to one embodiment of the present invention, a computer program product is also provided, which stores a computer program, wherein the computer program, when executed by a processor, implements the steps of the vehicle fault determination method described in any of the above claims.

[0023] In this embodiment of the invention, by acquiring multiple fuel tank pressure values ​​of a vehicle and classifying them, multiple sets of fuel tank pressure values ​​are obtained. Each set of fuel tank pressure values ​​has the same frequency. This achieves the purpose of performing Fourier transform processing on multiple sets of fuel tank pressure values ​​to obtain multiple pressure amplitudes. Each set of fuel tank pressure values ​​corresponds to one pressure amplitude, thereby achieving the technical effect of determining the vehicle's fault condition based on multiple pressure amplitudes. This can solve the technical problem of low accuracy in fault diagnosis of low-load desorption flow in the prior art. Attached Figure Description

[0024] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0025] Figure 1 This is a flowchart of a method for determining vehicle faults according to one embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of a vehicle engine electronic control system according to one embodiment of the present invention;

[0027] Figure 3This is a flowchart of a method for determining a low-load desorption flow rate fault according to one embodiment of the present invention;

[0028] Figure 4 This is a structural block diagram of a vehicle fault determination device according to one embodiment of the present invention;

[0029] Figure 5 This is a structural block diagram of an electronic device according to one embodiment of the present invention. Detailed Implementation

[0030] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0031] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0032] According to an embodiment of the present invention, an embodiment of a method for determining vehicle faults is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system containing at least a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0033] This method embodiment can also be executed in an electronic device, similar control device, or vehicle-mounted terminal that includes a memory and a processor. Taking a vehicle-mounted terminal as an example, the vehicle-mounted terminal may include one or more processors and a memory for storing data. Optionally, the vehicle-mounted terminal may also include a communication device for communication functions and a display device. Those skilled in the art will understand that the above structural description is merely illustrative and does not limit the structure of the vehicle-mounted terminal. For example, the vehicle-mounted terminal may include more or fewer components than those described above, or have a different configuration than those described above.

[0034] A processor may include one or more processing units. For example, a processor may include a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processing (DSP) chip, a microprocessor, a field-programmable gate array (FPGA), a neural network processing unit (NPU), a tensor processing unit (TPU), or an artificial intelligence (AI) type processor. Different processing units may be independent components or integrated into one or more processors. In some instances, electronic devices may also include one or more processors.

[0035] The memory can be used to store computer programs, such as the computer program corresponding to the vehicle fault determination method in this embodiment of the invention. The processor implements the vehicle fault determination method by running the computer program stored in the memory. The memory may include high-speed random access memory and non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory may further include memory remotely located relative to the processor, and these remote memories can be connected to the electronic device via a grid. Examples of such grids include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0036] The communication device is used to receive or transmit data via a grid. Specific examples of the aforementioned grid may include a wireless grid provided by the mobile terminal's communication provider. In one example, the communication device includes a network interface controller (NIC), which can connect to other grid devices via a base station to communicate with the Internet. In another example, the communication device may be a radio frequency (RF) module used for wireless communication with the Internet. In some embodiments of this solution, the communication device is used to connect to mobile devices such as mobile phones and tablets, enabling the mobile device to send commands to the vehicle-mounted terminal.

[0037] The display device can be a touchscreen liquid crystal display (LCD) or a touch display (also referred to as a "touchscreen" or "touch display screen"). This LCD allows the user to interact with the user interface of the in-vehicle terminal. In some embodiments, the in-vehicle terminal has a graphical user interface (GUI), allowing the user to interact with the GUI through finger contact and / or gestures on a touch-sensitive surface. The human-machine interaction function may include a vehicle gear shifting function, and executable instructions for performing these functions are configured / stored in one or more processor-executable computer program products or readable storage media.

[0038] Figure 1 This is a flowchart of a method for determining vehicle faults according to one embodiment of the present invention, such as... Figure 1 As shown, the method includes the following steps:

[0039] Step S101: Obtain the pressure values ​​of multiple fuel tanks of the vehicle.

[0040] Optionally, the execution subject in this embodiment is a vehicle fault determination system. It should be noted that other electronic devices and processors can also be used as execution subjects, and no further limitations are made here.

[0041] In the technical solution provided by step S101 of the present invention, firstly, the system needs to determine whether the preset monitoring enable conditions are met. Specifically, the monitoring enable conditions are usually that the data acquisition process is started only after the engine is idling and the request duty cycle of the charcoal canister solenoid valve is greater than a certain threshold (e.g., 10% by default) and maintained for a period of time (e.g., 3 seconds by default).

[0042] Furthermore, the system is configured with a fixed sampling frequency (i.e., sampling rate) and sampling duration (or total number of sampling points). Optionally, the sampling frequency can be set to 100Hz, meaning 100 data points are collected per second. Within a specified time window, the electronic control unit (ECU) cyclically reads the analog or digital signals output by the fuel tank pressure sensor at the set frequency and converts them into numerical values, storing them in memory. When the number of collected data points reaches a preset value (e.g., 250), the current acquisition stops, forming a complete pressure data sample set.

[0043] The aforementioned fuel tank pressure refers to the pressure in the vapor phase space inside the vehicle's fuel tank. In the evaporative emission control system, when the charcoal canister solenoid valve opens for desorption, the negative pressure in the intake manifold is transmitted to the fuel tank, causing a change in the internal pressure of the fuel tank (usually an increase in negative pressure).

[0044] The aforementioned idling condition refers to the state in which the engine maintains its lowest stable speed under no external load (or only basic accessory load). In this state, the vacuum in the intake manifold is relatively stable, which helps to eliminate interference from complex airflow under other high-load conditions on diagnosis.

[0045] The sampling frequency mentioned above refers to the number of times the signal is sampled per unit time, and the unit is Hz (Hertz).

[0046] As an optional implementation, the ECU monitors engine speed and load to confirm entry into idle mode. When the charcoal canister solenoid valve duty cycle is greater than 10% for 3 seconds, a timer interrupt is activated. Furthermore, the system is configured with an analog-to-digital converter that triggers at 10ms (corresponding to 100Hz), reading the voltage value from the fuel tank pressure sensor each time and converting it to a pressure value. The read value is stored in an array, and a counter i increments. Finally, when i reaches 250, the interrupt is disabled, data acquisition is marked as valid, and the process proceeds to the next step.

[0047] As an alternative implementation, the system monitors the intake manifold pressure and engine speed in real time to confirm a low-load desorption flushing state. Further, the system continuously reads the raw fuel tank pressure signal at a frequency of 50Hz (once every 20ms). The 50 raw data points read per second are filtered using a moving average to remove high-frequency spikes, generating 10 smoothed pressure values ​​per second. Finally, when the diagnostic trigger condition is met, 20 smoothed pressure values ​​from 2 seconds prior to the current moment are extracted to form a dataset for subsequent analysis.

[0048] It is worth noting that by acquiring multiple discrete pressure values, a pressure sequence that varies over time is formed, providing a data foundation for converting time-domain signals into frequency-domain signals (such as performing Fourier transforms). Furthermore, the invisible pressure fluctuations inside the fuel tank are transformed into processable digital values, enabling the system to accurately quantify the amplitude and frequency characteristics of fuel tank pressure fluctuations during the operation of the charcoal canister solenoid valve.

[0049] Step S102: Classify the multiple oil tank pressure values ​​to obtain multiple groups of oil tank pressure values, wherein the frequency of each group of oil tank pressure values ​​is the same.

[0050] In the technical solution provided in step S102 of the present invention, the multiple tank pressure values ​​(e.g., 250 pressure values) collected in the above steps are combined into a discrete time series array. A transformation algorithm is applied to this time series array, which can calculate the component intensity of the signal at different frequencies. Furthermore, the components of the pressure signal are divided according to the same or similar frequency values. For example, all signal energy belonging to 10Hz is grouped into one group, and all signal energy belonging to 20Hz is grouped into another group.

[0051] The aforementioned frequency refers to the number of times a signal completes a periodic change per unit time, measured in Hertz (Hz). Specifically, in this application, it refers to the rate of fluctuation in tank pressure. For example, if the charcoal canister solenoid valve operates at a frequency of 10Hz, it will cause a 10Hz fluctuation in tank pressure.

[0052] As an optional implementation, a set of bandpass digital filters with center frequencies of 10Hz, 20Hz, 30Hz, etc., are used to input the real-time collected tank pressure values ​​one by one into this set of filters. Specifically, the 10Hz bandpass filter only allows signals near 10Hz to pass through, and the 20Hz filter only allows signals near 20Hz to pass through.

[0053] It is worth noting that by breaking down and classifying the complex pressure fluctuation signals that are mixed together according to the frequency dimension, a quantifiable data foundation is provided for subsequent fault diagnosis based on frequency characteristics.

[0054] Step S103: Perform Fourier transform on multiple sets of oil tank pressure values ​​to obtain multiple pressure amplitudes, wherein each set of oil tank pressure values ​​corresponds to one pressure amplitude.

[0055] In the technical solution provided in step S103 of the present invention, the system first performs DC removal processing on each group of input tank pressure values ​​(time domain signal), that is, subtracts the mean value of the data group to avoid amplitude spikes at 0Hz masking effective information. Subsequently, in order to reduce spectral leakage caused by non-periodic signal truncation, the pressure value sequence is smoothed by multiplying it by a window function (such as a Hanning window).

[0056] Furthermore, a Fourier operation is performed on each set of preprocessed discrete pressure signals. This algorithm maps the pressure sequence in the time domain to the frequency domain, outputting a set of complex numbers. Each complex number contains a real part and an imaginary part, representing the projection intensity of that frequency component onto a cosine wave and a sine wave, respectively.

[0057] Furthermore, the absolute value (i.e., modulus, calculated as the square root of the real part squared plus the square of the imaginary part) of each complex number sequence is calculated to obtain the original amplitude at that frequency. Finally, the amplitude is normalized or energy corrected according to the number of sampling points (for example, during single-sided spectrum conversion, the amplitude at the intermediate frequency is multiplied by 2 and divided by the total number of sampling points) to obtain the pressure amplitude that accurately reflects physical pressure.

[0058] The aforementioned Fourier Transform (FFT) is a mathematical algorithm that converts a signal from the time domain to the frequency domain. Specifically, in this application, the algorithm decomposes the time-varying fuel tank pressure curve into a superposition of multiple sine waves of different frequencies, thereby identifying specific frequency components.

[0059] In frequency domain analysis, the pressure amplitude mentioned above represents the intensity or energy of pressure fluctuations at a specific frequency.

[0060] As an optional implementation, the ECU stores the collected multiple sets of fuel tank pressure values ​​into a memory buffer and calls the internal digital signal processing library functions to perform FFT operations. After the operation is completed, the complex modulus value at the corresponding frequency index is directly read according to the set frequency resolution. After normalization by dividing by the number of sampling points, the pressure amplitude of each set is output.

[0061] As an alternative implementation, the system can also forgo global FFT and instead design a dedicated digital bandpass filter for each target frequency group. The tank pressure value sequence is input into the corresponding bandpass filter to filter out interference from other frequencies. Then, the root mean square (RMS) value of the filter output signal is calculated, and this RMS value is directly used as the pressure amplitude for that frequency group.

[0062] It is worth noting that the above technical steps can successfully transform complex pressure fluctuations that are difficult to observe and compare directly in the time domain into quantifiable pressure amplitude indicators in the frequency domain, making the signal characteristics more intuitive. Furthermore, multiple sets of pressure fluctuation intensities (amplitudes) at different frequencies can be extracted independently and simultaneously, providing an interference-resistant data foundation for subsequent accurate identification of system states at specific frequencies (such as pipeline blockage or leakage).

[0063] Step S104: Determine the vehicle's fault condition based on multiple pressure amplitudes.

[0064] In the technical solution provided by step S104 of the present invention, the system calls a preset fault judgment threshold from the memory according to the current operating conditions (such as idling, specific load, etc.). The threshold usually includes the upper limit of the amplitude under normal conditions and the graded threshold used to distinguish between small leakage and large leakage.

[0065] Furthermore, the multiple pressure amplitudes extracted in the previous step are compared one by one or in combination with the corresponding thresholds. For example, it is determined whether the pressure amplitude at a specific frequency exceeds the normal physical fluctuation range. Based on the comparison results, preset diagnostic logic is executed. Specifically, if the amplitude characteristics meet the fault triggering conditions, it is determined that the vehicle has a corresponding fault (such as pipeline leakage or blockage), and a corresponding fault code (DTC) is generated or the instrument panel fault indicator light is illuminated.

[0066] The aforementioned fault determination thresholds refer to boundary values ​​obtained in advance through extensive bench tests or actual vehicle calibration. Since the normal pressure fluctuation amplitude varies at different frequencies, the system needs to set reasonable upper and lower limits for the amplitude at each frequency as a criterion for determining whether a physical fault has occurred in the current system.

[0067] The above fault codes are standardized codes generated by the system when it determines that a vehicle has malfunctioned based on the pressure amplitude. These codes are used to characterize the specific type of fault (such as leakage in the evaporative emission system) and make it easier for maintenance personnel to read and locate the problem using a diagnostic tool.

[0068] As an optional implementation, the ECU reads the 10Hz fundamental frequency amplitude A1 and the 20Hz harmonic amplitude A2. Further, the system compares A1 with a leakage threshold T1 and A2 with a harmonic threshold T2. Only when both A1 and A2 are greater than T1 and greater than T2, is a major leakage fault in the vehicle ultimately determined. This method effectively prevents false alarms caused by occasional interference from road bumps or other factors affecting a single frequency.

[0069] As an alternative implementation, the system can also assign weighting coefficients to pressure amplitudes of different frequencies (e.g., a weight of 0.6 for 10Hz amplitude and 0.4 for 20Hz amplitude). Further, each extracted pressure amplitude is multiplied by its corresponding weighting coefficient and summed to obtain a comprehensive fault score. When this comprehensive score exceeds a preset fault confirmation threshold, the vehicle is determined to have malfunctioned.

[0070] It is worth noting that the above technical steps can transform abstract frequency domain data (pressure amplitude) into a clear diagnostic conclusion (normal / leakage / blockage) that the vehicle control system can execute and record. Furthermore, since the judgment process is based on a comprehensive evaluation of the amplitudes of multiple frequencies, the system can effectively filter out occasional noise interference at a single frequency point, significantly reducing the false alarm rate and false negative rate of fault diagnosis.

[0071] Steps S101 to S104 above show that, in this invention, by acquiring multiple fuel tank pressure values ​​of the vehicle and classifying them, multiple sets of fuel tank pressure values ​​are obtained. Each set of fuel tank pressure values ​​has the same frequency. This achieves the purpose of performing Fourier transform processing on multiple sets of fuel tank pressure values ​​to obtain multiple pressure amplitudes. Each set of fuel tank pressure values ​​corresponds to one pressure amplitude, thereby achieving the technical effect of determining the vehicle's fault condition based on multiple pressure amplitudes. This can solve the technical problem of low accuracy in fault diagnosis of low-load desorption flow in the prior art.

[0072] The method described in this embodiment will now be described in further detail.

[0073] Step S201: Obtain the fault status of multiple vehicle components, including the charcoal canister solenoid valve, air flow meter, intake manifold pressure sensor, and ambient pressure sensor.

[0074] In step S202, in response to the absence of electrical faults in multiple vehicle components, multiple fuel tank pressure values ​​of the vehicle are obtained.

[0075] In this embodiment, such as Figure 2 As shown, the electronic control unit (ECU) first performs a status scan on the designated key components (canister solenoid valve, air flow meter, intake manifold pressure sensor, ambient pressure sensor) and reads the current circuit parameters (such as voltage, resistance or signal frequency) of each sensor and actuator.

[0076] Furthermore, based on the read parameters, the system determines whether there are any electrical abnormalities in each component. For example, it checks whether the signal voltage is consistently too high (short circuit), consistently too low (open circuit), or whether the signal exceeds a reasonable physical range. The ECU will only trigger the next data acquisition command when the electrical status of all the aforementioned components is determined to be normal, starting to read data from the fuel tank pressure sensor at a set sampling frequency to obtain multiple fuel tank pressure values. It is worth noting that if any of the aforementioned components has an electrical fault, the system will terminate or suspend the diagnostic process.

[0077] The aforementioned charcoal canister solenoid valve is an actuator in the fuel evaporative emission control system, used to control the timing and flow rate of fuel vapor adsorbed in the activated carbon canister entering the engine intake manifold.

[0078] The aforementioned intake manifold pressure sensor is used to measure the absolute pressure or vacuum in the intake manifold and convert it into a voltage signal that is fed back to the ECU. This is an important basis for calculating engine load and intake volume.

[0079] The aforementioned electrical faults refer to physical damage or abnormalities that occur in the circuit connection or signal transmission of components. They are usually manifested as short circuits, open circuits, poor contact in the circuit, or the electrical signal output by the sensor continuously deviating from the normal operating range (such as the normal range of 0.5V-4.5V).

[0080] As an optional implementation, the ECU reads the memory to check for any pending or confirmed electrical fault codes related to these four components. Simultaneously, it reads the current signal values ​​of these four components in real time to determine if the voltages of the intake manifold pressure sensor and ambient pressure sensor are within the valid range of 0.5V-4.5V, and whether the control circuit of the charcoal canister solenoid valve is conductive. If both checks are normal, a timer is started to acquire fuel tank pressure values ​​at a frequency of 100Hz.

[0081] As an alternative implementation, when the vehicle is powered on or enters a specific diagnostic condition, the ECU automatically performs a low-level electrical self-test for these four components. If the self-test passes, the ECU sets the "EVAP diagnostic enable flag" to 1 in memory; if the self-test fails, the flag is set to 0. Furthermore, the main diagnostic program continuously reads this flag; when the flag is detected as 1, it directly calls the fuel tank pressure acquisition subroutine to obtain the pressure value; if it is 0, the acquisition is skipped to avoid invalid diagnostics.

[0082] It is worth noting that pre-verification ensures that the input variables involved in the desorption flow calculation (such as intake manifold pressure, ambient pressure, etc.) are accurate and reliable, avoiding erroneous diagnosis due to sensor malfunction. Furthermore, it effectively prevents invalid pressure acquisition and complex frequency domain calculations under electrical fault conditions, saving ECU computing resources and significantly reducing the risk of false alarms.

[0083] Step S301: In response to the vehicle's engine being in an idling state, the duty cycle of the charcoal canister solenoid valve is obtained.

[0084] Step S302: Compare the duty cycle of the carbon canister solenoid valve with the duty cycle threshold to obtain the first comparison result;

[0085] Step S303: In response to the first comparison result indicating that the duty cycle is greater than the duty cycle threshold, obtain the duration of the duty cycle.

[0086] Step S304: Compare the duration segment with the preset time segment to obtain a second comparison result;

[0087] Step S305: In response to the second comparison result indicating that the duration of the time interval is longer than a preset time interval, multiple oil tank pressure values ​​are obtained.

[0088] In this embodiment, the ECU (electronic control unit) first confirms that the engine is idling and reads the duty cycle value of the PWM (pulse width modulation) signal that is currently controlling the carbon canister solenoid valve in real time.

[0089] Furthermore, the system compares the actual duty cycle read with a preset duty cycle threshold (e.g., 10%). If the duty cycle is greater than the threshold, it indicates that the solenoid valve opening is sufficient to generate effective desorption flow, and the first comparison result is obtained. After the first condition is met, the system starts an internal timer to accumulate and record the duration for which the duty cycle is continuously greater than the threshold, thus obtaining the duration of the duty cycle.

[0090] Furthermore, the system compares the accumulated duration with a preset time period (e.g., 3 seconds). If the duration is longer than the preset time period, a second comparison result is obtained. Only when both of the above conditions are met will the ECU officially issue a command to begin acquiring multiple fuel tank pressure values ​​at the set sampling frequency.

[0091] The duty cycle mentioned above refers to the percentage of time the canister purge solenoid valve is in the on (open) state within one pulse cycle, relative to the entire cycle time. The ECU precisely controls the opening degree of the canister purge solenoid valve by adjusting the duty cycle, thereby controlling the amount of fuel vapor entering the intake manifold.

[0092] The aforementioned idling condition refers to the state in which the engine maintains its lowest stable operating speed under no external load. In this state, the vacuum level in the intake manifold is relatively stable, which helps to eliminate interference from complex operating conditions on diagnosis.

[0093] As an optional implementation, the ECU monitors engine speed in the main cycle. After confirming the entry into idle mode, it reads the duty cycle of the carbon canister solenoid valve. If the duty cycle is greater than 10%, the "desorption flow rate target flag" in memory is set to 1, and a timer is started. Furthermore, if the timer's accumulated time is greater than 3 seconds, the "diagnostic enable flag" is set to 1. Finally, when the data acquisition subroutine detects that the diagnostic enable flag is 1, it immediately starts the ADC (analog-to-digital converter) to acquire the fuel tank pressure value at a frequency of 100Hz.

[0094] As an alternative implementation, the ECU continuously samples the duty cycle of the carbon canister solenoid valve at fixed intervals (e.g., 10ms). Furthermore, the system maintains a sliding time window, calculating in real-time the cumulative time within which the duty cycle is greater than 10%. When the cumulative effective time within the sliding window exceeds 3 seconds, the system determines that the desorption state is stable and directly triggers the data reading task from the fuel tank pressure sensor in the interrupt service routine.

[0095] It is worth noting that through rigorous verification of dual conditions (duty cycle threshold and duration), it is ensured that the carbon canister solenoid valve is in a stable and effective desorption flushing state when the pressure acquisition is triggered, providing an input signal with significant physical characteristics for subsequent frequency domain analysis. Furthermore, the system can effectively filter transient airflow fluctuations when the solenoid valve first opens at the initial idle speed, as well as weak desorption flow caused by an excessively small duty cycle, avoiding false diagnostics due to unclear signal characteristics or unstable operating conditions.

[0096] Step S401: Convert multiple sets of oil tank pressure values ​​into multiple sets of oil tank pressure signals;

[0097] Step S402: Remove the DC component from multiple sets of oil tank pressure signals to obtain multiple sets of pressure signals to be processed;

[0098] Step S403: Window the multiple sets of pressure signals to be processed to obtain multiple sets of target pressure signals;

[0099] Step S404: Perform Fourier transform processing on multiple sets of target pressure signals to obtain multiple pressure amplitudes.

[0100] In this embodiment, multiple discretely acquired tank pressure values ​​(such as in array form) are arranged and mapped according to the time sampling order, and converted into a standard time-domain tank pressure signal sequence.

[0101] Furthermore, the system calculates the arithmetic mean (i.e., DC component) of the pressure signal sequence and subtracts this mean from each pressure value in the sequence, aiming to eliminate the static base pressure in the signal that does not change over time and retain only the dynamically fluctuating AC component.

[0102] Furthermore, in order to suppress spectral leakage caused by signal truncation, the mean-free pressure signal sequence is multiplied point-by-point in the time domain with a specific window function (such as the Hanning window). This allows the two ends of the signal sequence to decay smoothly to zero, reducing energy diffusion caused by aperiodic signal truncation.

[0103] Finally, the Fast Fourier Transform (FFT) algorithm is executed on the windowed target pressure signal sequence to map the time-domain signal to the frequency domain and calculate the magnitude of the complex result at each frequency point, thereby accurately extracting multiple pressure amplitudes.

[0104] In signal processing, the aforementioned DC component refers to the component in a signal with a frequency of 0. In the tank pressure signal, it represents the current static absolute pressure or baseline pressure level of the system and does not contain any information about periodic fluctuations.

[0105] The aforementioned spectral leakage refers to the fact that, because the actual acquired signal is of finite length (equivalent to a rectangular window truncation of an infinitely long signal), the real energy of the signal will diffuse (leak) to adjacent frequency points during Fourier transform, resulting in spectral distortion.

[0106] The window function described above is a mathematical function used in signal processing. Multiplying a signal by a window function in the time domain can smooth the transition at truncation boundaries, thereby effectively suppressing spectral leakage and improving the accuracy of frequency domain analysis.

[0107] It is worth noting that by removing the DC component, a large amplitude spike at 0Hz is avoided, preventing it from masking the effective low-frequency fluctuation signal and improving the purity of frequency domain feature extraction. Furthermore, windowing operations smooth the signal boundaries, significantly reducing energy diffusion to adjacent frequency points, making the extracted pressure amplitude at specific frequencies more accurate and realistically reflect the actual energy of physical fluctuations.

[0108] Step S501: Compare multiple pressure amplitudes with amplitude thresholds respectively to obtain a third comparison result;

[0109] Step S502: In response to the third comparison result indicating that any pressure amplitude among multiple pressure amplitudes is greater than the amplitude threshold, it is determined that the vehicle does not have a low-load desorption flow fault.

[0110] Step S503: In response to the third comparison result indicating that multiple pressure amplitudes are less than or equal to the amplitude threshold, it is determined that the vehicle has a low-load desorption flow fault.

[0111] In this embodiment, such as Figure 3 As shown, the system compares the multiple pressure amplitudes (such as fundamental frequency amplitude, harmonic amplitude, etc.) extracted by Fourier transform in the previous step with the preset amplitude thresholds one by one to generate the comparison results for each frequency point.

[0112] Furthermore, the system executes a normal operation logic if any one of the multiple pressure amplitudes is satisfied. If any one of these amplitudes exceeds a threshold, the system immediately terminates the fault determination, confirming that the vehicle does not have a low-load desorption flow fault. This indicates that as long as there is a sufficiently strong pressure fluctuation at a specific frequency, it proves that the pipeline has normal desorption flow.

[0113] Furthermore, the system can also execute a fault-only logic where all conditions are met. That is, if the system iterates through all pressure amplitudes and finds that they are all less than or equal to the amplitude threshold, the system ultimately confirms that the vehicle has a low-load desorption flow fault. This indicates that at all monitoring frequencies, there is a lack of normal pressure fluctuation characteristics, and the pipeline is most likely in a state of blockage or insufficient flow.

[0114] The aforementioned amplitude threshold refers to a pre-calibrated critical value used to measure whether the energy of pressure fluctuations in the oil tank meets the standard. This threshold represents the minimum energy level of pressure fluctuations at a specific frequency under normal desorption flow.

[0115] The aforementioned low-load desorption flow fault refers to a fault condition in which, under low engine load conditions, the fuel vapor flow rate entering the intake manifold is lower than the system's preset normal standard due to reasons such as blockage of the carbon canister desorption pipeline, solenoid valve sticking, or pipeline leakage, which affects vehicle driving stability and emissions.

[0116] As an optional implementation, the ECU simultaneously inputs multiple pressure amplitude values ​​and amplitude thresholds into a hardware comparator array. If any comparator outputs a high-level signal greater than the threshold, the hardware circuit immediately triggers an interrupt, clears the fault flag, and directly outputs a no-fault conclusion, without waiting for subsequent amplitude comparisons, greatly saving judgment time. Furthermore, if all comparators output low levels (all less than or equal to the threshold) and all polling is completed, the fault flag is set, and a conclusion of low-load desorption flow fault is output.

[0117] As an alternative implementation, the ECU can also initialize an anomaly counter to 0. The software iterates through all pressure amplitudes, incrementing the counter by 1 for each amplitude exceeding a threshold. After the loop, the counter value is checked: if the counter is greater than 0, no fault exists; if the counter is 0 (i.e., all amplitudes are less than or equal to the threshold), a low-load desorption flow fault exists.

[0118] It is worth noting that the logic of determining normal operation based on any pressure amplitude exceeding a threshold ensures that the system can quickly confirm pipeline patency as long as it captures effective desorption fluctuation characteristics at any frequency point, effectively avoiding false alarms caused by signal attenuation at a single frequency point. Furthermore, the system employs stringent conditions, requiring multiple pressure amplitudes to be less than or equal to a threshold before determining a fault. This ensures that a fault is only reported when normal flow characteristics are lacking across all monitoring dimensions, significantly improving the accuracy and reliability of fault diagnosis for low-load desorption flow.

[0119] Step S601: In response to the vehicle completing the fault diagnosis of low load desorption flow, update the in-use monitoring frequency of low load desorption flow.

[0120] In this embodiment, the ECU monitors the running status of the low-load desorption flow fault diagnosis program in real time and determines whether the diagnosis process in the current driving cycle has been fully executed (i.e., whether the conclusion of "pass" or "fail" has been reached).

[0121] Furthermore, once the system confirms the diagnosis is complete, it immediately updates the In-Use Monitoring Frequency (IUPR) counters. Specifically, as part of the frequency update, the system increments the numerator in the IUPR calculation formula by 1. In the statistical logic of IUPR, the numerator typically represents the number of completed diagnoses or the number of available diagnostic opportunities. Increasing the numerator by 1 signifies that the system has officially recorded a successful and effective diagnostic attempt for this diagnostic cycle.

[0122] The aforementioned low-load desorption flow fault diagnosis refers to the detection process under low engine load conditions, which involves actively controlling the opening of the carbon canister solenoid valve and utilizing the characteristics of fuel tank pressure fluctuations to determine whether the desorption pipeline of the evaporation system is unobstructed or whether the flow rate meets the standard.

[0123] The In-Use Monitoring Frequency (IUPR) mentioned above refers to the frequency with which a vehicle's emission diagnostic system performs specific diagnostic monitoring during actual operation. It is typically a ratio used to measure the adequacy of the diagnostic system's ability to perform diagnostics within a specified mileage or time period. Vehicles are required to complete a sufficient number of diagnostics within a certain period to ensure the reliability of the emission control system.

[0124] As an optional implementation, the ECU has an internal diagnostic end flag. This flag is set to "1" after the fault diagnosis logic (such as amplitude comparison) reaches a conclusion. When the main loop program detects that this flag is "1", it immediately reads the current IUPR numerator value stored in non-volatile memory (such as EEPROM). After incrementing this value by 1, it writes it directly back to memory and clears the diagnostic end flag, preparing for the next diagnosis.

[0125] As an alternative implementation, when the diagnostic module completes its judgment and generates a result, a high-priority diagnostic completion interrupt is triggered. In the interrupt service routine, the IUPR molecular variable cached in RAM is directly incremented by 1. Furthermore, when the vehicle is turned off or at a specific synchronization point, the system writes the updated molecular values ​​from RAM to the Flash memory in batches to reduce frequent memory erase / write operations.

[0126] It is worth noting that by immediately incrementing the numerator by 1 after the diagnosis, the completion status of each diagnosis cycle can be accurately and comprehensively recorded, providing reliable basic data for subsequent IUPR calculations. Furthermore, this technology directly supports the statistical requirements of vehicle emission diagnostic systems for IUPR, ensuring that the system can track the frequency of diagnostic execution in real time, thereby guaranteeing that the vehicle meets the mandatory requirements for diagnostic coverage throughout its entire lifecycle.

[0127] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods according to the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or grid device, etc.) to execute the methods of the various embodiments of the present invention.

[0128] This embodiment also provides a vehicle fault determination device, which is used to implement the above embodiments and preferred embodiments, and will not be repeated as already described. As used below, the term "module" can be a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0129] Figure 4 This is a structural block diagram of a vehicle fault determination device 400 according to one embodiment of the present invention, such as... Figure 4 As shown, the device includes: a first acquisition module 41, a classification module 42, a processing module 43, and a determination module 44.

[0130] The first acquisition module 41 is used to acquire multiple fuel tank pressure values ​​of the vehicle;

[0131] The classification module 42 is used to classify multiple oil tank pressure values ​​to obtain multiple groups of oil tank pressure values, wherein each group of oil tank pressure values ​​has the same frequency.

[0132] Processing module 43 is used to perform Fourier transform processing on multiple sets of oil tank pressure values ​​to obtain multiple pressure amplitudes, wherein each set of oil tank pressure values ​​corresponds to one pressure amplitude.

[0133] The determination module 44 is used to determine the vehicle's fault condition based on multiple pressure amplitudes.

[0134] Optionally, the vehicle fault determination device 400 further includes: a second acquisition module for acquiring fault conditions of multiple vehicle components, wherein the multiple vehicle components include a canister solenoid valve, an air flow meter, an intake manifold pressure sensor, and an ambient pressure sensor; and a third acquisition module for acquiring multiple fuel tank pressure values ​​of the vehicle in response to the absence of electrical faults in the multiple vehicle components.

[0135] Optionally, the vehicle fault determination device 400 further includes: a fourth acquisition module, used to acquire the duty cycle of the charcoal canister solenoid valve in response to the vehicle's engine being in an idling state; a first comparison module, used to compare the duty cycle of the charcoal canister solenoid valve with a duty cycle threshold to obtain a first comparison result; a fifth acquisition module, used to acquire the duration of the duty cycle in response to the first comparison result indicating that the duty cycle is greater than the duty cycle threshold; a second comparison module, used to compare the duration with a preset time period to obtain a second comparison result; and a sixth acquisition module, used to acquire multiple fuel tank pressure values ​​in response to the second comparison result indicating that the duration is greater than the preset time period.

[0136] Optionally, the processing module 43 includes: a conversion unit for converting multiple sets of tank pressure values ​​into multiple sets of tank pressure signals; a first operation unit for removing the DC component from the multiple sets of tank pressure signals to obtain multiple sets of pressure signals to be processed; a second operation unit for windowing the multiple sets of pressure signals to be processed to obtain multiple sets of target pressure signals; and a processing unit for performing Fourier transform processing on the multiple sets of target pressure signals to obtain multiple pressure amplitudes.

[0137] Optionally, the determining module 44 includes: a comparison unit for comparing multiple pressure amplitudes with amplitude thresholds respectively to obtain a third comparison result; a first determining unit for determining that the vehicle does not have a low-load desorption flow fault in response to the third comparison result indicating that any pressure amplitude among the multiple pressure amplitudes is greater than the amplitude threshold; and a second determining unit for determining that the vehicle has a low-load desorption flow fault in response to the third comparison result indicating that all multiple pressure amplitudes are less than or equal to the amplitude threshold.

[0138] Optionally, the vehicle fault determination device 400 further includes an update module for updating the in-use monitoring frequency of the low-load desorption flow in response to a fault diagnosis of the vehicle completing the low-load desorption flow.

[0139] Embodiments of the present invention also provide a vehicle, including a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to perform the above-described method for determining vehicle faults.

[0140] Optionally, in this embodiment, the vehicle may be configured to store a computer program for performing the following steps:

[0141] Step S101: Obtain multiple fuel tank pressure values ​​of the vehicle;

[0142] Step S102: Classify the multiple oil tank pressure values ​​to obtain multiple groups of oil tank pressure values, wherein the frequency of each group of oil tank pressure values ​​is the same.

[0143] Step S103: Perform Fourier transform on multiple sets of oil tank pressure values ​​to obtain multiple pressure amplitudes, wherein each set of oil tank pressure values ​​corresponds to one pressure amplitude.

[0144] Step S104: Determine the vehicle's fault condition based on multiple pressure amplitudes.

[0145] Optionally, the processor, when executing the program, also performs the following steps: acquiring fault conditions of multiple vehicle components, including a canister solenoid valve, an air flow meter, an intake manifold pressure sensor, and an ambient pressure sensor; and acquiring multiple fuel tank pressure values ​​of the vehicle in response to the absence of electrical faults in the multiple vehicle components.

[0146] Optionally, the processor, when executing the program, further implements the following steps: in response to the vehicle's engine being in an idling state, obtaining the duty cycle of the charcoal canister solenoid valve; comparing the duty cycle of the charcoal canister solenoid valve with a duty cycle threshold to obtain a first comparison result; in response to the first comparison result indicating that the duty cycle is greater than the duty cycle threshold, obtaining a duration segment of the duty cycle; comparing the duration segment with a preset time period to obtain a second comparison result; in response to the second comparison result indicating that the duration segment is greater than the preset time period, obtaining multiple fuel tank pressure values.

[0147] Optionally, the processor may also perform the following steps when executing the program: converting multiple sets of tank pressure values ​​into multiple sets of tank pressure signals; removing the DC component from the multiple sets of tank pressure signals to obtain multiple sets of pressure signals to be processed; windowing the multiple sets of pressure signals to be processed to obtain multiple sets of target pressure signals; and performing Fourier transform processing on the multiple sets of target pressure signals to obtain multiple pressure amplitudes.

[0148] Optionally, the processor, when executing the program, also performs the following steps: comparing multiple pressure amplitudes with amplitude thresholds respectively to obtain a third comparison result; in response to the third comparison result indicating that any pressure amplitude among the multiple pressure amplitudes is greater than the amplitude threshold, determining that the vehicle does not have a low-load desorption flow fault; in response to the third comparison result indicating that all multiple pressure amplitudes are less than or equal to the amplitude threshold, determining that the vehicle has a low-load desorption flow fault.

[0149] Optionally, the processor also performs the following steps when executing the program: updating the in-use monitoring frequency of the low-load desorption flow in response to a fault diagnosis of the vehicle completing the low-load desorption flow.

[0150] Optionally, specific examples in this embodiment can refer to the examples described in the above embodiments and optional implementations, and will not be repeated here.

[0151] Embodiments of the present invention also provide an electronic device, such as... Figure 5As shown, it includes a memory 51 and a processor 52, wherein the memory stores a computer program and the processor is configured to run the computer program to perform the above-described method for determining vehicle faults.

[0152] Optionally, in this embodiment, the electronic device may be configured to store a computer program for performing the following steps:

[0153] Step S101: Obtain multiple fuel tank pressure values ​​of the vehicle;

[0154] Step S102: Classify the multiple oil tank pressure values ​​to obtain multiple groups of oil tank pressure values, wherein the frequency of each group of oil tank pressure values ​​is the same.

[0155] Step S103: Perform Fourier transform on multiple sets of oil tank pressure values ​​to obtain multiple pressure amplitudes, wherein each set of oil tank pressure values ​​corresponds to one pressure amplitude.

[0156] Step S104: Determine the vehicle's fault condition based on multiple pressure amplitudes.

[0157] Optionally, the processor, when executing the program, also performs the following steps: acquiring fault conditions of multiple vehicle components, including a canister solenoid valve, an air flow meter, an intake manifold pressure sensor, and an ambient pressure sensor; and acquiring multiple fuel tank pressure values ​​of the vehicle in response to the absence of electrical faults in the multiple vehicle components.

[0158] Optionally, the processor, when executing the program, further implements the following steps: in response to the vehicle's engine being in an idling state, obtaining the duty cycle of the charcoal canister solenoid valve; comparing the duty cycle of the charcoal canister solenoid valve with a duty cycle threshold to obtain a first comparison result; in response to the first comparison result indicating that the duty cycle is greater than the duty cycle threshold, obtaining a duration segment of the duty cycle; comparing the duration segment with a preset time period to obtain a second comparison result; in response to the second comparison result indicating that the duration segment is greater than the preset time period, obtaining multiple fuel tank pressure values.

[0159] Optionally, the processor may also perform the following steps when executing the program: converting multiple sets of tank pressure values ​​into multiple sets of tank pressure signals; removing the DC component from the multiple sets of tank pressure signals to obtain multiple sets of pressure signals to be processed; windowing the multiple sets of pressure signals to be processed to obtain multiple sets of target pressure signals; and performing Fourier transform processing on the multiple sets of target pressure signals to obtain multiple pressure amplitudes.

[0160] Optionally, the processor, when executing the program, also performs the following steps: comparing multiple pressure amplitudes with amplitude thresholds respectively to obtain a third comparison result; in response to the third comparison result indicating that any pressure amplitude among the multiple pressure amplitudes is greater than the amplitude threshold, determining that the vehicle does not have a low-load desorption flow fault; in response to the third comparison result indicating that all multiple pressure amplitudes are less than or equal to the amplitude threshold, determining that the vehicle has a low-load desorption flow fault.

[0161] Optionally, the processor also performs the following steps when executing the program: updating the in-use monitoring frequency of the low-load desorption flow in response to a fault diagnosis of the vehicle completing the low-load desorption flow.

[0162] Optionally, specific examples in this embodiment can refer to the examples described in the above embodiments and optional implementations, and will not be repeated here.

[0163] Embodiments of the present invention also provide a computer-readable storage medium storing a computer program configured to perform the above-described method for determining vehicle faults when run on a computer or processor.

[0164] Optionally, in this embodiment, the computer-readable storage medium may be configured to store a computer program for performing the following steps:

[0165] Step S101: Obtain multiple fuel tank pressure values ​​of the vehicle;

[0166] Step S102: Classify the multiple oil tank pressure values ​​to obtain multiple groups of oil tank pressure values, wherein the frequency of each group of oil tank pressure values ​​is the same.

[0167] Step S103: Perform Fourier transform on multiple sets of oil tank pressure values ​​to obtain multiple pressure amplitudes, wherein each set of oil tank pressure values ​​corresponds to one pressure amplitude.

[0168] Step S104: Determine the vehicle's fault condition based on multiple pressure amplitudes.

[0169] Optionally, the storage medium is configured to store program code for performing the following steps: acquiring fault conditions of multiple vehicle components, including a canister solenoid valve, an air flow meter, an intake manifold pressure sensor, and an ambient pressure sensor; and acquiring multiple fuel tank pressure values ​​of the vehicle in response to the absence of electrical faults in the multiple vehicle components.

[0170] Optionally, the storage medium is configured to store program code for performing the following steps: in response to the vehicle's engine being in an idling state, obtaining the duty cycle of the charcoal canister solenoid valve; comparing the duty cycle of the charcoal canister solenoid valve with a duty cycle threshold to obtain a first comparison result; in response to the first comparison result indicating that the duty cycle is greater than the duty cycle threshold, obtaining a duration segment of the duty cycle; comparing the duration segment with a preset time period to obtain a second comparison result; in response to the second comparison result indicating that the duration segment is greater than the preset time period, obtaining multiple fuel tank pressure values.

[0171] Optionally, the storage medium is configured to store program code for performing the following steps: converting multiple sets of tank pressure values ​​into multiple sets of tank pressure signals; removing the DC component from the multiple sets of tank pressure signals to obtain multiple sets of pressure signals to be processed; windowing the multiple sets of pressure signals to be processed to obtain multiple sets of target pressure signals; and performing Fourier transform processing on the multiple sets of target pressure signals to obtain multiple pressure amplitudes.

[0172] Optionally, the storage medium is configured to store program code for performing the following steps: comparing multiple pressure amplitudes with amplitude thresholds respectively to obtain a third comparison result; determining that the vehicle does not have a low-load desorption flow fault in response to the third comparison result indicating that any pressure amplitude among the multiple pressure amplitudes is greater than the amplitude threshold; and determining that the vehicle has a low-load desorption flow fault in response to the third comparison result indicating that all multiple pressure amplitudes are less than or equal to the amplitude threshold.

[0173] Optionally, the storage medium is configured to store program code for performing the following steps: updating the in-use monitoring frequency of the low-load desorption flow in response to a fault diagnosis of the vehicle completing the low-load desorption flow.

[0174] Optionally, specific examples in this embodiment can refer to the examples described in the above embodiments and optional implementations, and will not be repeated here.

[0175] Embodiments of the present invention also provide a computer program product, including a computer program, wherein the computer program, when executed by a processor, implements the steps of the above-described method for determining vehicle faults.

[0176] Optionally, in this embodiment, the computer program product described above may be configured to store a computer program for performing the following steps:

[0177] Step S101: Obtain multiple fuel tank pressure values ​​of the vehicle;

[0178] Step S102: Classify the multiple oil tank pressure values ​​to obtain multiple groups of oil tank pressure values, wherein the frequency of each group of oil tank pressure values ​​is the same.

[0179] Step S103: Perform Fourier transform on multiple sets of oil tank pressure values ​​to obtain multiple pressure amplitudes, wherein each set of oil tank pressure values ​​corresponds to one pressure amplitude.

[0180] Step S104: Determine the vehicle's fault condition based on multiple pressure amplitudes.

[0181] Optionally, the computer program may also perform the following steps when executing the program: acquiring fault conditions of multiple vehicle components, including a canister solenoid valve, an air flow meter, an intake manifold pressure sensor, and an ambient pressure sensor; and acquiring multiple fuel tank pressure values ​​of the vehicle in response to the absence of electrical faults in the multiple vehicle components.

[0182] Optionally, the computer program further performs the following steps when executing the program: in response to the vehicle's engine being in an idling state, obtaining the duty cycle of the charcoal canister solenoid valve; comparing the duty cycle of the charcoal canister solenoid valve with a duty cycle threshold to obtain a first comparison result; in response to the first comparison result indicating that the duty cycle is greater than the duty cycle threshold, obtaining a duration segment of the duty cycle; comparing the duration segment with a preset time period to obtain a second comparison result; in response to the second comparison result indicating that the duration segment is greater than the preset time period, obtaining multiple fuel tank pressure values.

[0183] Optionally, the computer program may further perform the following steps when executing the program: converting multiple sets of tank pressure values ​​into multiple sets of tank pressure signals; removing the DC component from the multiple sets of tank pressure signals to obtain multiple sets of pressure signals to be processed; windowing the multiple sets of pressure signals to be processed to obtain multiple sets of target pressure signals; and performing Fourier transform processing on the multiple sets of target pressure signals to obtain multiple pressure amplitudes.

[0184] Optionally, when the computer program executes the program, it further implements the following steps: comparing multiple pressure amplitudes with amplitude thresholds respectively to obtain a third comparison result; in response to the third comparison result indicating that any pressure amplitude among the multiple pressure amplitudes is greater than the amplitude threshold, determining that the vehicle does not have a low-load desorption flow fault; in response to the third comparison result indicating that all multiple pressure amplitudes are less than or equal to the amplitude threshold, determining that the vehicle has a low-load desorption flow fault.

[0185] Optionally, the computer program may also perform the following steps when executing the program: in response to the vehicle completing a fault diagnosis of low-load desorption flow, update the in-use monitoring frequency of low-load desorption flow.

[0186] Optionally, specific examples in this embodiment can refer to the examples described in the above embodiments and optional implementations, and will not be repeated here.

[0187] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0188] In the embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some interfaces; indirect couplings or communication connections between units or modules may be electrical or other forms.

[0189] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0190] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0191] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or grid device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0192] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for determining vehicle faults, characterized in that, include: Obtain the pressure values ​​of multiple fuel tanks in the vehicle; The multiple tank pressure values ​​are classified to obtain multiple groups of tank pressure values, wherein each group of tank pressure values ​​has the same frequency. The multiple sets of oil tank pressure values ​​are subjected to Fourier transform processing to obtain multiple pressure amplitudes, wherein each set of oil tank pressure values ​​corresponds to one pressure amplitude. The vehicle's fault condition is determined based on the multiple pressure amplitudes.

2. The method for determining vehicle faults according to claim 1, characterized in that, The method further includes: The system acquires fault information for multiple vehicle components, including a charcoal canister solenoid valve, an air flow meter, an intake manifold pressure sensor, and an ambient pressure sensor. In response to the absence of electrical faults in the plurality of vehicle components, the pressure values ​​of the plurality of fuel tanks of the vehicle are obtained.

3. The method for determining vehicle faults according to claim 2, characterized in that, The method further includes: In response to the vehicle's engine being in an idling state, the duty cycle of the charcoal canister solenoid valve is obtained; The duty cycle and duty cycle threshold of the solenoid valve of the charcoal canister are compared to obtain the first comparison result; In response to the first comparison result indicating that the duty cycle is greater than the duty cycle threshold, the duration of the duty cycle is obtained; The duration segment is compared with the preset time period to obtain a second comparison result; In response to the second comparison result indicating that the duration is greater than the preset time period, the pressure values ​​of the plurality of oil tanks are obtained.

4. The method for determining vehicle faults according to claim 1, characterized in that, The Fourier transform processing of the multiple sets of tank pressure values ​​yields the multiple pressure amplitudes, including: The multiple sets of oil tank pressure values ​​are converted into multiple sets of oil tank pressure signals; The DC component of the multiple sets of tank pressure signals is removed to obtain multiple sets of pressure signals to be processed. Windowing is applied to the multiple sets of pressure signals to be processed to obtain multiple sets of target pressure signals; The Fourier transform processing is performed on the multiple sets of target pressure signals to obtain the multiple pressure amplitudes.

5. The method for determining vehicle faults according to claim 1, characterized in that, Determining the fault condition based on the multiple pressure amplitudes includes: The multiple pressure amplitudes are compared with amplitude thresholds to obtain a third comparison result; In response to the third comparison result indicating that any one of the plurality of pressure amplitudes is greater than the amplitude threshold, it is determined that the vehicle does not have a low-load desorption flow fault. In response to the third comparison result indicating that all of the plurality of pressure amplitudes are less than or equal to the amplitude threshold, it is determined that the vehicle has the low-load desorption flow fault.

6. The method for determining vehicle faults according to claim 1, characterized in that, The method further includes: In response to a fault diagnosis that the vehicle has completed a low-load desorption flow rate, the in-use monitoring frequency of the low-load desorption flow rate is updated.

7. A device for determining vehicle malfunctions, characterized in that, include: The first acquisition module is used to acquire multiple fuel tank pressure values ​​of the vehicle; The classification module is used to classify the multiple oil tank pressure values ​​to obtain multiple groups of oil tank pressure values, wherein each group of oil tank pressure values ​​has the same frequency. The processing module is used to perform Fourier transform processing on the multiple sets of oil tank pressure values ​​to obtain multiple pressure amplitudes, wherein each set of oil tank pressure values ​​corresponds to one pressure amplitude. The determination module is used to determine the fault status of the vehicle based on the multiple pressure amplitudes.

8. An electronic device comprising a memory and a processor, characterized in that, The memory stores a computer program, and the processor is configured to run the computer program to perform the vehicle fault determination method as described in any one of claims 1 to 6.

9. A vehicle comprising a memory and a processor, characterized in that, The memory stores a computer program, and the processor is configured to run the computer program to perform the vehicle fault determination method as described in any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, wherein the computer program is configured to execute the vehicle fault determination method as described in any one of claims 1 to 6 when run on a computer or processor.

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