A vehicle uninterrupted power leakage detection method and system

Abstract

This invention relates to the field of vehicle electrical system testing technology, specifically to a method and system for detecting vehicle leakage current without power interruption. The method includes: acquiring vehicle status signals and determining the vehicle's current operating condition; if the vehicle's current operating condition is a sleep preparation state, outputting a sleep guidance command to control a dual-path uninterrupted power supply module to establish an uninterrupted power supply detection path; connecting the detection device in parallel with the vehicle's battery negative terminal circuit to form a bypass path, switching to a series state while maintaining the power supply to the vehicle's electronic control unit, thus obtaining a series detection circuit; acquiring current signals and performing conversion and amplification processing to obtain an amplified voltage signal, then performing multi-dimensional error compensation processing to generate compensated current data; if the vehicle is determined to have entered a stable sleep state, comparing the compensated current data with a preset threshold to generate a leakage current determination result; and outputting a detection report. This invention achieves uninterrupted power supply detection in all scenarios, avoids data loss, and improves detection accuracy and efficiency.

Description

Technical Field

[0001] This invention relates to the field of vehicle electrical system testing technology, specifically to a method and system for detecting leakage current in vehicles without power interruption. Background Technology

[0002] As automotive electronic and electrical architectures become increasingly complex, problems such as excessive dark current or dormant current generated when the vehicle is in a quiet state, leading to battery depletion, vehicle starting failure, reduced range in new energy vehicles, and even electrical fires, are becoming increasingly prominent. Accurate and efficient detection of low-voltage leakage faults is a crucial aspect of automotive repair and maintenance.

[0003] Traditional detection methods have three major contradictions:

[0004] First, there is a conflict between the need for detection and system protection. The standard method for detecting dormant current is to disconnect the negative terminal of the battery and connect an ammeter in series after the vehicle enters dormant mode. However, disconnecting the power will cause the loss of a large amount of memory data (such as adaptive learning values, clock, and seat position) in electronic control units (ECUs) such as the engine, transmission, windows, and audio system. When the vehicle is powered on again, it will require cumbersome matching, reset, or learning, and may even generate fault codes, leading to customer complaints.

[0005] Second, there is a conflict between operational complexity and repair efficiency. Traditional methods typically require two people: one to unplug and plug fuses to locate the leakage circuit, and the other to monitor the ammeter reading. A single complete test can take more than two hours, significantly consuming valuable repair workstation resources.

[0006] Third, there is a contradiction between measurement accuracy and fault identification. The current range accuracy of multimeters commonly used in repair shops is usually ±(1%-3%), which is insufficient for identifying micro-current leakage faults of ≤10mA, easily leading to misdiagnosis. In addition, when removing or inserting fuses, the module will generate a momentary large current surge due to power failure and restart, often causing ordinary multimeter fuses to burn out.

[0007] The existing solution involves using a multimeter with a clamp-on ammeter for continuous testing. Specifically, the technician uses a high-sensitivity clamp-on meter to clamp onto the negative terminal of the battery, without disconnecting the circuit, and directly reads the current value.

[0008] This solution has the following technical defects and limitations:

[0009] Serious issues with accuracy and zero drift: Clamp meters are based on the Hall effect or fluxgate principle, making them susceptible to interference from ambient magnetic fields and causing severe zero drift. They cannot accurately measure small DC currents below 50mA and cannot meet the accuracy requirements for detecting dormant currents (20-50mA).

[0010] Inability to cover all scenarios: When it is necessary to disconnect the line to connect a more accurate shunt or troubleshoot a specific node, this solution is helpless and cannot achieve true "end-to-end" uninterrupted power detection.

[0011] Lack of intelligent operating condition guidance: The equipment only provides current values ​​and cannot identify whether the vehicle has truly entered a "sleep" state. Maintenance personnel can only rely on experience to wait for the current to stabilize and cannot determine which module is working, resulting in low diagnostic efficiency. Summary of the Invention

[0012] To address the aforementioned technical problems, this invention provides a method and system for detecting leakage current in vehicles without power interruption, aiming to achieve uninterrupted power interruption detection in all scenarios, avoid data loss and system malfunction, and improve detection accuracy and efficiency.

[0013] To achieve the above objectives, the present invention provides the following technical solution:

[0014] On one hand, embodiments of the present invention provide a method for detecting leakage current in a vehicle without power interruption, the method comprising the following steps:

[0015] S100, acquire vehicle status signal, the vehicle status signal includes ignition switch status, engine speed and door open / close status;

[0016] S200, determine the current operating condition of the vehicle based on the vehicle status signal. If the current operating condition of the vehicle is a hibernation preparation condition, output a hibernation guidance command to control the dual-path uninterrupted power supply module to establish an uninterrupted power supply detection path.

[0017] S300, the detection device is connected in parallel with the negative terminal circuit of the vehicle battery through the dual-path uninterrupted power supply module to form a bypass path, and then switched to a series state while maintaining the power supply state of the vehicle electronic control unit to obtain a series detection circuit.

[0018] S400 acquires the current signal of the series detection circuit through a high-precision bidirectional current detection module, and converts and amplifies the current signal to obtain an amplified voltage signal;

[0019] S500, performs multi-dimensional error compensation processing on the amplified voltage signal, the multi-dimensional error compensation processing includes zero-point calibration, temperature compensation and nonlinear correction, and generates compensated current data;

[0020] S600, determine whether the vehicle has entered a stable sleep state based on the vehicle status signal and the compensated current data. If it has entered a stable sleep state, compare the compensated current data with a preset threshold to generate a leakage current determination result.

[0021] S700 outputs a detection report based on the leakage current determination result.

[0022] Optionally, in S300, the step of connecting the detection device and the negative terminal circuit of the vehicle battery in parallel through the dual-path uninterrupted power supply module to form a bypass path, and switching to a series state while maintaining the power supply state of the vehicle electronic control unit, to obtain a series detection circuit, includes:

[0023] S310, clamp the battery terminal of the parallel-to-series wiring harness to the negative terminal of the vehicle battery, and clamp the wiring harness terminal of the parallel-to-series wiring harness to the negative terminal of the vehicle wiring harness, forming a bypass path in parallel with the original circuit of the vehicle.

[0024] S320, maintain the power supply current of the vehicle electronic control unit through the bypass path, disconnect the fixing bolt of the negative terminal harness of the battery, and disconnect the original series circuit of the vehicle.

[0025] S330, the bypass path seamlessly transfers the current output from the vehicle battery to the inside of the testing equipment, and the testing equipment automatically switches from a parallel state to a series state with the circuit under test, thus obtaining a series testing circuit.

[0026] Optionally, in S300, the step of connecting the detection device and the negative terminal circuit of the vehicle battery in parallel through the dual-path uninterrupted power supply module to form a bypass path, and switching to a series state while maintaining the power supply state of the vehicle electronic control unit to obtain a series detection circuit, further includes:

[0027] S340, the OBD power supply harness is inserted into the vehicle's OBD interface. The detection device obtains vehicle battery power from the constant power pin of the OBD interface. The detection device obtains vehicle data through the ground pin and network pin of the OBD interface.

[0028] S350, after disconnecting the positive and negative terminals of the vehicle battery, the detection device continuously supplies power to the vehicle's critical networks through the OBD power supply harness and continuously monitors the voltage and calculates the current.

[0029] Optionally, in S400, the step of acquiring the current signal of the series detection circuit through a high-precision bidirectional current detection module, and converting and amplifying the current signal to obtain an amplified voltage signal includes:

[0030] S410, the current signal flowing through the series detection circuit is acquired through a DC shunt, and the DC shunt converts the current signal into a millivolt-level bidirectional voltage signal;

[0031] S420, the millivolt-level bidirectional voltage signal is input to a differential amplifier, and the differential amplifier performs differential amplification on the millivolt-level bidirectional voltage signal to obtain an amplified voltage signal.

[0032] Optionally, in S500, the multi-dimensional error compensation processing performed on the amplified voltage signal includes zero-point calibration, temperature compensation, and nonlinear correction to generate compensated current data, including:

[0033] S510, Record the system output value as the zero-point offset value in the state of no current input. In subsequent measurements, subtract the zero-point offset value from the measurement results to obtain the zero-point calibrated data.

[0034] S520 collects ambient temperature data through an onboard temperature sensor, and corrects the temperature drift error of the shunt and differential amplifier caused by temperature changes in real time based on the ambient temperature data to obtain temperature-compensated data.

[0035] The S530 uses a pre-calibrated multi-point correction curve and a polynomial fitting algorithm to correct nonlinear errors across the entire measurement range, generating compensated current data.

[0036] Optionally, in S600, the step of determining whether the vehicle has entered a stable sleep state based on the vehicle status signal and the compensated current data, and if it has entered a stable sleep state, comparing the compensated current data with a preset threshold to generate a leakage current determination result, includes:

[0037] S610, based on the vehicle status signal, identify changes in the vehicle ignition switch status, engine speed and door open / close status, and determine whether the vehicle is currently in a wake-up state, a pre-dormant state, a dormant state or a driving state.

[0038] S620, displays the compensated current data in real time, generates a dynamic curve of current changing with time, and marks each plateau period in the current decrease process;

[0039] S630, when the vehicle is detected to have entered a stable sleep state, the current compensated current data is compared with the preset sleep current threshold. If the current compensated current data is greater than the preset sleep current threshold, a leakage current exceeding the standard judgment result is generated.

[0040] S640, while maintaining the uninterrupted power detection path, removes the fuses of the suspected branches one by one, records and displays the current change before and after removing each fuse, identifies the branch with the largest current change as the main leakage branch, and generates leakage branch location information.

[0041] Optionally, in S700, the step of outputting a detection report based on the leakage current determination result includes:

[0042] S710, integrate the compensated current data, the leakage current determination result, the current operating condition of the vehicle and the leakage current branch location information into a detection report;

[0043] S720 presents the test report in the form of a chart through the display and interaction unit. The chart includes a curve of current change over time, a comparison chart of current changes in each branch, and a conclusion on leakage current determination.

[0044] On the other hand, embodiments of the present invention provide a vehicle uninterrupted power leakage detection system, comprising:

[0045] At least one processor;

[0046] At least one memory for storing at least one program;

[0047] When the at least one program is executed by the at least one processor, the at least one processor performs the method described above.

[0048] On the other hand, embodiments of the present invention provide a computer-readable storage medium storing a processor-executable program, which, when executed by a processor, is used to perform the above-described method.

[0049] On the other hand, embodiments of the present invention provide a vehicle uninterrupted power leakage detection device, comprising:

[0050] A dual-path uninterruptible power supply module, comprising a parallel-to-serial wiring harness and an OBD power supply wiring harness, wherein the parallel-to-serial wiring harness comprises a battery terminal clamp and a wiring harness terminal clamp, and the OBD power supply wiring harness comprises a connector that matches the vehicle's OBD interface.

[0051] A high-precision bidirectional current detection module includes a DC shunt, a differential amplifier, and a microcontroller unit. The DC shunt is connected in series in the detection circuit. The input terminal of the differential amplifier is connected to both ends of the DC shunt, and the output terminal of the differential amplifier is connected to the input terminal of the microcontroller unit.

[0052] The intelligent control and data processing module includes a working condition identification unit and a display and interaction unit. The working condition identification unit acquires vehicle status signals through a CAN bus or hard-wired signals, and the display and interaction unit is used to output sleep guidance commands and detection reports.

[0053] The embodiments of the present invention have the following beneficial effects:

[0054] This invention achieves uninterrupted power supply throughout the detection process through a dual-path uninterrupted power supply module, completely solving the problems of data loss and system instability caused by the need for power interruption in traditional leakage current detection. The dual-path design includes two independent technical paths: parallel-to-series wiring harnesses and OBD power supply harnesses, covering all scenarios from accurate total current measurement to rapid troubleshooting.

[0055] This invention employs a hardware circuit combining a high-precision DC shunt and a differential amplifier, along with a multi-dimensional error compensation algorithm, to reduce the overall system measurement error to within ±0.1%, enabling reliable identification of milliampere-level micro-current leakage faults. The detection accuracy is 10-30 times higher than that of traditional solutions.

[0056] This invention identifies vehicle operating conditions through an intelligent control and data processing module, intelligently guiding maintenance personnel into the correct testing process. It transforms the complex leakage current diagnosis process into a guided operation on the screen, reducing the testing time for a single person from more than 2 hours to within 20 minutes, increasing efficiency by 6 times, and significantly reducing reliance on the experience level of maintenance personnel.

[0057] This invention achieves seamless switching through parallel-to-series technology without disconnecting the negative terminal of the battery, allowing all electronic control units in the vehicle to maintain their original power supply status and operating mode. This fundamentally eliminates data loss and system malfunctions caused by testing, achieving zero-risk, uninterrupted power testing. Attached Figure Description

[0058] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0059] Figure 1 This is a flowchart illustrating the vehicle uninterrupted power leakage detection method in an embodiment of the present invention;

[0060] Figure 2 This is a schematic diagram of the architecture of the vehicle uninterrupted power leakage detection device in an embodiment of the present invention. Detailed Implementation

[0061] The following will provide a clear and complete description of the concept, specific structure, and technical effects of the present invention in conjunction with embodiments and accompanying drawings, so as to fully understand the purpose, solution, and effects of the present invention. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0062] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the embodiments of this invention; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this invention as detailed in the appended claims.

[0063] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this invention is for descriptive purposes only and is not intended to limit the invention.

[0064] refer to Figure 1 ,like Figure 1 The figure shows a method for detecting leakage current in a vehicle without power interruption provided by an embodiment of the present invention. The method includes the following steps:

[0065] S100, acquire vehicle status signal, the vehicle status signal includes ignition switch status, engine speed and door open / close status;

[0066] S200, determine the current operating condition of the vehicle based on the vehicle status signal. If the current operating condition of the vehicle is a hibernation preparation condition, output a hibernation guidance command to control the dual-path uninterrupted power supply module to establish an uninterrupted power supply detection path.

[0067] S300, the detection device is connected in parallel with the negative terminal circuit of the vehicle battery through the dual-path uninterrupted power supply module to form a bypass path, and then switched to a series state while maintaining the power supply state of the vehicle electronic control unit to obtain a series detection circuit.

[0068] S400 acquires the current signal of the series detection circuit through a high-precision bidirectional current detection module, and converts and amplifies the current signal to obtain an amplified voltage signal;

[0069] S500, performs multi-dimensional error compensation processing on the amplified voltage signal, the multi-dimensional error compensation processing includes zero-point calibration, temperature compensation and nonlinear correction, and generates compensated current data;

[0070] S600, determine whether the vehicle has entered a stable sleep state based on the vehicle status signal and the compensated current data. If it has entered a stable sleep state, compare the compensated current data with a preset threshold to generate a leakage current determination result.

[0071] S700 outputs a detection report based on the leakage current determination result.

[0072] This invention provides a method and system for detecting vehicle leakage current without power interruption. By employing a dual-path uninterrupted power supply module, the entire detection process is kept powered on, completely resolving the data loss and system instability issues caused by the requirement for power disconnection in traditional leakage current detection methods. Through a high-precision bidirectional current detection module combined with multi-dimensional error compensation processing, the overall system measurement error is reduced to within ±0.1%, enabling reliable identification of milliampere-level micro-current leakage faults. The intelligent control and data processing module identifies vehicle operating conditions and guides the detection process, transforming the complex leakage current diagnosis process into on-screen guided operations, significantly improving detection efficiency and user-friendliness.

[0073] The core of this embodiment lies in the vehicle uninterrupted power leakage detection system, which achieves uninterrupted power leakage detection through dual-path power supply maintenance, high-precision bidirectional current detection, and intelligent operating condition recognition.

[0074] The vehicle uninterruptible power leakage detection system provided in this embodiment of the invention includes: a dual-path uninterruptible power supply module (including parallel-to-series wiring harness and OBD power supply wiring harness), a high-precision bidirectional current detection module (including DC shunt, differential amplifier, and microcontroller unit), an intelligent control and data processing module (including operating condition identification unit, display and interaction unit), and vehicle interfaces (battery terminal, OBD interface, and fuse box).

[0075] Dual-path uninterruptible power supply module:

[0076] This module is the core hardware foundation of this invention, providing two independent uninterrupted power detection paths:

[0077] Path 1: Parallel to series connection technology.

[0078] Operation and Principle: ① Clamp the battery terminal clamp on the "parallel to series wiring harness" of this device to the negative terminal of the vehicle battery, and simultaneously clamp the wiring harness terminal clamp to the negative wiring harness terminal, forming a bypass path in parallel with the vehicle's circuitry. ② At this point, the testing device is connected in parallel with the vehicle's original circuitry, and the internal current detection circuit of the device begins to operate. ③ The maintenance personnel remove the fixing bolts of the battery negative wiring harness, disconnecting the original series connection. Due to the existence of the parallel bypass path, the current seamlessly transfers to the testing device, ensuring uninterrupted vehicle power supply. At this time, the device automatically switches from parallel to series connection with the circuit under test, and begins to accurately measure the total current.

[0079] Advantages: It achieves seamless and uninterrupted conversion from parallel to series connection, making it the gold standard for accurate measurement of total current.

[0080] Path 2: OBD power supply and measurement technology.

[0081] Operation and Principle: ① Insert the device's OBD power supply harness into the vehicle's OBD interface. The device draws power from the vehicle's battery through the constant-power pin (Pin16) of the OBD interface and begins operation. ② Simultaneously, the device can independently measure voltage and acquire vehicle data through the ground pin (Pin4 / 5) and network pins (such as the CAN bus) of the OBD interface. ③ Even if the battery's positive and negative terminals are disconnected, the device can still supply power to some critical vehicle networks and continuously monitor voltage and calculate current.

[0082] Advantages: No need to touch the battery terminals, the operation is the simplest, suitable for quick troubleshooting or "power preservation" of the vehicle after disconnecting the main power.

[0083] High-precision bidirectional current detection module:

[0084] Hardware circuitry: The core components are a high-precision DC shunt (0.5-level accuracy) and a differential amplifier (such as INA128). The DC shunt is connected in series in the main circuit, feeding the weak bidirectional voltage signal (mV level) generated at its two ends into the differential amplifier. The amplifier's high common-mode rejection ratio (CMRR>110dB) effectively suppresses electromagnetic interference generated by engines, generators, etc.

[0085] Software compensation algorithm: After the microcontroller acquires the voltage signal output by the differential amplifier, it runs a multi-dimensional error compensation algorithm:

[0086] 1. Zero-point calibration: When there is no current input, record the system output value as the zero-point offset and subtract it in subsequent measurements.

[0087] 2. Temperature compensation: The onboard temperature sensor corrects the temperature drift error of the DC shunt and differential amplifier caused by temperature changes in real time.

[0088] 3. Nonlinear correction: Using pre-calibrated multi-point curves, a polynomial fitting algorithm is employed to perform software correction of nonlinear errors across the entire measurement range.

[0089] Final result: The overall measurement error of the system is reduced from ±1%-3% in the traditional solution to within ±0.1%, achieving bidirectional, high-precision measurement of current from 1mA to 1000A.

[0090] Intelligent control and data processing module:

[0091] Operating condition identification: The device acquires information such as the vehicle's ignition switch status (OFF / ACC / ON / START), engine speed, and door open / close status in real time via CAN bus or hard-wired signals, and intelligently determines whether the vehicle is currently in a wake-up, pre-sleep, sleep, or driving state.

[0092] Core decision-making logic (dormant current test procedure):

[0093] 1. Guided vehicle lock and sleep mode: The interactive interface prompts "Please turn off all electrical appliances, lock the doors, and wait for the vehicle to go into sleep mode."

[0094] 2. Monitoring the hibernation process: Real-time display of the current value and a dynamically changing current-time curve. The system automatically marks each plateau period during the current decrease process and can prompt "Body Control Module (BCM) enters standby" and "Engine ECU hibernates".

[0095] 3. Determining excessive leakage current: Once the system detects that the vehicle has entered a stable sleep state, it compares the current value with a preset threshold (e.g., 50mA). If the current exceeds the threshold, the interface will display an alarm: "Abnormal sleep current detected."

[0096] 4. Assisted Locating of Leakage Points: While maintaining uninterrupted power, maintenance personnel can remove suspected fuses one by one according to system prompts. The system will automatically record and display the current change before and after removing each fuse. The branch with the largest change is the main leakage branch, presented in a graphical format.

[0097] In some embodiments, in S300, the step of connecting the detection device and the negative terminal circuit of the vehicle battery in parallel through the dual-path uninterrupted power supply module to form a bypass path, and switching to a series state while maintaining the power supply state of the vehicle electronic control unit, to obtain a series detection circuit, includes:

[0098] S310, clamp the battery terminal of the parallel-to-series wiring harness to the negative terminal of the vehicle battery, and clamp the wiring harness terminal of the parallel-to-series wiring harness to the negative terminal of the vehicle wiring harness, forming a bypass path in parallel with the original circuit of the vehicle.

[0099] S320, maintain the power supply current of the vehicle electronic control unit through the bypass path, disconnect the fixing bolt of the negative terminal harness of the battery, and disconnect the original series circuit of the vehicle.

[0100] S330, the bypass path seamlessly transfers the current output from the vehicle battery to the inside of the testing equipment, and the testing equipment automatically switches from a parallel state to a series state with the circuit under test, thus obtaining a series testing circuit.

[0101] This embodiment achieves seamless switching between the testing equipment and the vehicle's circuitry by converting a parallel-to-series wiring harness. After connecting the battery terminal clamp and wiring harness terminal clamp to the negative battery terminal and the negative wiring harness terminal respectively, a parallel bypass path is formed, ensuring uninterrupted power supply to the vehicle's electronic control unit when the original series connection is disconnected. After disconnecting the fixing bolts, the current seamlessly transfers to the testing equipment through the bypass path, achieving a state switch from parallel to series connection, resulting in a series testing circuit. This allows for the series connection of the testing equipment without interrupting the vehicle's power supply.

[0102] In some embodiments, S300, the step of connecting the detection device and the negative terminal circuit of the vehicle battery in parallel through the dual-path uninterrupted power supply module to form a bypass path, and switching to a series state while maintaining the power supply state of the vehicle electronic control unit to obtain a series detection circuit, further includes:

[0103] S340, the OBD power supply harness is inserted into the vehicle's OBD interface. The detection device obtains vehicle battery power from the constant power pin of the OBD interface. The detection device obtains vehicle data through the ground pin and network pin of the OBD interface.

[0104] S350, after disconnecting the positive and negative terminals of the vehicle battery, the detection device continuously supplies power to the vehicle's critical networks through the OBD power supply harness and continuously monitors the voltage and calculates the current.

[0105] This embodiment utilizes the OBD power supply harness to achieve an alternative uninterrupted testing path. After inserting the OBD power supply harness into the vehicle's OBD interface, the testing device draws operating power from the constant power pins and independently measures voltage and acquires vehicle data via the ground and network pins. Even after disconnecting the vehicle battery's positive and negative terminals, the testing device can still continuously supply power to the vehicle's critical networks through the OBD power supply harness, maintaining the operational status of some vehicle modules and continuously monitoring voltage and calculating current. This enables rapid troubleshooting and power preservation functions without touching the battery terminals.

[0106] In some embodiments, in S400, the step of acquiring the current signal of the series detection circuit through a high-precision bidirectional current detection module, and converting and amplifying the current signal to obtain an amplified voltage signal includes:

[0107] S410, the current signal flowing through the series detection circuit is acquired through a DC shunt, and the DC shunt converts the current signal into a millivolt-level bidirectional voltage signal;

[0108] S420, the millivolt-level bidirectional voltage signal is input to a differential amplifier, and the differential amplifier performs differential amplification on the millivolt-level bidirectional voltage signal to obtain an amplified voltage signal.

[0109] This embodiment uses a DC shunt to convert a current signal into a voltage signal. The DC shunt is connected in series in the detection circuit. When current flows through it, a bidirectional voltage drop in the millivolt range, proportional to the current, is generated across its terminals. This weak voltage signal is differentially amplified by a differential amplifier. The high common-mode rejection ratio of the differential amplifier effectively suppresses electromagnetic interference generated by the engine, generator, etc., resulting in a stable and reliable amplified voltage signal. This provides high-quality raw data for subsequent error compensation and leakage current determination.

[0110] In some embodiments, in S500, the multi-dimensional error compensation processing performed on the amplified voltage signal includes zero-point calibration, temperature compensation, and nonlinear correction to generate compensated current data, including:

[0111] S510, Record the system output value as the zero-point offset value in the state of no current input. In subsequent measurements, subtract the zero-point offset value from the measurement results to obtain the zero-point calibrated data.

[0112] S520 collects ambient temperature data through an onboard temperature sensor, and corrects the temperature drift error of the shunt and differential amplifier caused by temperature changes in real time based on the ambient temperature data to obtain temperature-compensated data.

[0113] The S530 uses a pre-calibrated multi-point correction curve and a polynomial fitting algorithm to correct nonlinear errors across the entire measurement range, generating compensated current data.

[0114] This embodiment improves current detection accuracy through multi-dimensional error compensation processing. The system output value is recorded as a zero-point offset value when there is no current input, and this offset value is subtracted in subsequent measurements to eliminate the system's inherent zero-point error. Ambient temperature data is collected in real time using an onboard temperature sensor, and the temperature drift error of the DC shunt and differential amplifier is corrected in real time based on temperature changes. Using pre-calibrated multi-point correction curves, a polynomial fitting algorithm is employed to correct nonlinear errors across the entire measurement range, ultimately generating high-precision compensated current data and reducing the overall system measurement error to within ±0.1%.

[0115] In some embodiments, in S600, determining whether the vehicle has entered a stable sleep state based on the vehicle status signal and the compensated current data, and if it has entered a stable sleep state, comparing the compensated current data with a preset threshold to generate a leakage current determination result, includes:

[0116] S610, based on the vehicle status signal, identify changes in the vehicle ignition switch status, engine speed and door open / close status, and determine whether the vehicle is currently in a wake-up state, a pre-dormant state, a dormant state or a driving state.

[0117] S620, displays the compensated current data in real time, generates a dynamic curve of current changing with time, and marks each plateau period in the current decrease process;

[0118] S630, when the vehicle is detected to have entered a stable sleep state, the current compensated current data is compared with the preset sleep current threshold. If the current compensated current data is greater than the preset sleep current threshold, a leakage current exceeding the standard judgment result is generated.

[0119] S640, while maintaining the uninterrupted power detection path, removes the fuses of the suspected branches one by one, records and displays the current change before and after removing each fuse, identifies the branch with the largest current change as the main leakage branch, and generates leakage branch location information.

[0120] This embodiment achieves intelligent dormant current testing through operating condition recognition. Based on vehicle status signals, it identifies changes in ignition switch status, engine speed, and door open / close status to intelligently determine whether the vehicle is currently in a wake-up state, pre-dormant state, dormant state, or driving state. It displays the compensated current data in real time and generates a dynamic curve of current changes over time, automatically marking each plateau period during the current decrease process, visually demonstrating the dormant progress of each vehicle module. Once the vehicle is detected to have entered a stable dormant state, the current compensated current data is compared with a preset dormant current threshold. If the current value exceeds the preset threshold, a leakage current exceeding the limit judgment result is generated. While maintaining an uninterrupted power detection path, the fuses of suspected branches are removed one by one, and the current change before and after each fuse removal is recorded and displayed. The branch with the largest current change is identified as the main leakage branch, generating leakage branch location information to achieve precise location of the leakage fault.

[0121] In some embodiments, in S700, the step of outputting a detection report based on the leakage current determination result includes:

[0122] S710, integrate the compensated current data, the leakage current determination result, the current operating condition of the vehicle and the leakage current branch location information into a detection report;

[0123] S720 presents the test report in the form of a chart through the display and interaction unit. The chart includes a curve of current change over time, a comparison chart of current changes in each branch, and a conclusion on leakage current determination.

[0124] This embodiment generates a complete inspection report by integrating multi-dimensional detection data. The compensated current data, leakage current determination results, vehicle current operating conditions, and leakage branch location information are integrated into a unified inspection report, which is presented intuitively in chart form through a display and interactive unit. The current-time curve shows the current change trend during vehicle sleep mode, the comparison chart of current changes in each branch clearly identifies the main leakage branches, and the leakage current determination conclusion clearly provides the inspection results, offering maintenance personnel a comprehensive and intuitive diagnostic basis.

[0125] refer to Figure 2 This invention provides a vehicle uninterruptible power leakage detection device, comprising:

[0126] A dual-path uninterruptible power supply module, comprising a parallel-to-serial wiring harness and an OBD power supply wiring harness, wherein the parallel-to-serial wiring harness comprises a battery terminal clamp and a wiring harness terminal clamp, and the OBD power supply wiring harness comprises a connector that matches the vehicle's OBD interface.

[0127] A high-precision bidirectional current detection module includes a DC shunt, a differential amplifier, and a microcontroller unit. The DC shunt is connected in series in the detection circuit. The input terminal of the differential amplifier is connected to both ends of the DC shunt, and the output terminal of the differential amplifier is connected to the input terminal of the microcontroller unit.

[0128] The intelligent control and data processing module includes a working condition identification unit and a display and interaction unit. The working condition identification unit acquires vehicle status signals through a CAN bus or hard-wired signals, and the display and interaction unit is used to output sleep guidance commands and detection reports.

[0129] The content of the above method embodiments is applicable to this embodiment. The specific functions implemented in this embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments. Therefore, they will not be repeated here.

[0130] This invention also provides a vehicle uninterrupted power leakage detection system, comprising:

[0131] At least one processor;

[0132] At least one memory for storing at least one program;

[0133] When the at least one program is executed by the at least one processor, the at least one processor performs the method described above.

[0134] The content of the above method embodiments is applicable to this embodiment. The specific functions implemented in this embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments. Therefore, they will not be repeated here.

[0135] This invention also provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the method described above. This electronic device can be any smart terminal, including tablet computers, in-vehicle computers, etc.

[0136] It is understood that the content of the above method embodiments is applicable to this device embodiment. The specific functions implemented by this device embodiment are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0137] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method.

[0138] It is understood that the content of the above method embodiments is applicable to this storage medium embodiment. The specific functions implemented in this storage medium embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.

[0139] This invention also provides a computer program product, including a computer program or computer instructions, which are stored in a memory. A processor of a computer device reads the computer program or computer instructions from the memory and executes the computer program or computer instructions, causing the computer device to perform the above-described method.

[0140] It is understood that the content of the above method embodiments is applicable to the embodiments of this program product. The specific functions implemented by the embodiments of this program product are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0141] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0142] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically include computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0143] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

Claims

1. A method for detecting leakage current in a vehicle without power interruption, characterized in that, The method includes the following steps: S100, acquire vehicle status signal, the vehicle status signal includes ignition switch status, engine speed and door open / close status; S200, determine the current operating condition of the vehicle based on the vehicle status signal. If the current operating condition of the vehicle is a hibernation preparation condition, output a hibernation guidance command to control the dual-path uninterrupted power supply module to establish an uninterrupted power supply detection path. S300, the detection device is connected in parallel with the negative terminal circuit of the vehicle battery through the dual-path uninterrupted power supply module to form a bypass path, and then switched to a series state while maintaining the power supply state of the vehicle electronic control unit to obtain a series detection circuit. S400 acquires the current signal of the series detection circuit through a high-precision bidirectional current detection module, and converts and amplifies the current signal to obtain an amplified voltage signal; S500, performs multi-dimensional error compensation processing on the amplified voltage signal, the multi-dimensional error compensation processing includes zero-point calibration, temperature compensation and nonlinear correction, and generates compensated current data; S600, determine whether the vehicle has entered a stable sleep state based on the vehicle status signal and the compensated current data. If it has entered a stable sleep state, compare the compensated current data with a preset threshold to generate a leakage current determination result. S700 outputs a detection report based on the leakage current determination result.

2. The method according to claim 1, characterized in that, In S300, the detection device is connected in parallel with the negative terminal circuit of the vehicle battery through the dual-path uninterrupted power supply module to form a bypass path. While maintaining the power supply to the vehicle's electronic control unit, it switches to a series state to obtain a series detection circuit, including: S310, clamp the battery terminal of the parallel-to-series wiring harness to the negative terminal of the vehicle battery, and clamp the wiring harness terminal of the parallel-to-series wiring harness to the negative terminal of the vehicle wiring harness, forming a bypass path in parallel with the original circuit of the vehicle. S320, maintain the power supply current of the vehicle electronic control unit through the bypass path, disconnect the fixing bolt of the negative terminal harness of the battery, and disconnect the original series circuit of the vehicle. S330, the bypass path seamlessly transfers the current output from the vehicle battery to the inside of the testing equipment, and the testing equipment automatically switches from a parallel state to a series state with the circuit under test, thus obtaining a series testing circuit.

3. The method according to claim 1, characterized in that, In S300, the method of connecting the detection device and the negative terminal circuit of the vehicle battery in parallel through the dual-path uninterrupted power supply module to form a bypass path, and switching to a series state while maintaining the power supply state of the vehicle electronic control unit to obtain a series detection circuit, further includes: S340, the OBD power supply harness is inserted into the vehicle's OBD interface. The detection device obtains vehicle battery power from the constant power pin of the OBD interface. The detection device obtains vehicle data through the ground pin and network pin of the OBD interface. S350, after disconnecting the positive and negative terminals of the vehicle battery, the detection device continuously supplies power to the vehicle's critical networks through the OBD power supply harness and continuously monitors the voltage and calculates the current.

4. The method according to claim 1, characterized in that, In S400, the process of acquiring the current signal of the series detection circuit through a high-precision bidirectional current detection module, and converting and amplifying the current signal to obtain an amplified voltage signal includes: S410, the current signal flowing through the series detection circuit is acquired through a DC shunt, and the DC shunt converts the current signal into a millivolt-level bidirectional voltage signal; S420, the millivolt-level bidirectional voltage signal is input to a differential amplifier, and the differential amplifier performs differential amplification on the millivolt-level bidirectional voltage signal to obtain an amplified voltage signal.

5. The method according to claim 1, characterized in that, In S500, the amplified voltage signal undergoes multi-dimensional error compensation processing, which includes zero-point calibration, temperature compensation, and nonlinear correction, generating compensated current data, including: S510, Record the system output value as the zero-point offset value in the state of no current input. In subsequent measurements, subtract the zero-point offset value from the measurement results to obtain the zero-point calibrated data. S520 collects ambient temperature data through an onboard temperature sensor, and corrects the temperature drift error of the shunt and differential amplifier caused by temperature changes in real time based on the ambient temperature data to obtain temperature-compensated data. The S530 uses a pre-calibrated multi-point correction curve and a polynomial fitting algorithm to correct nonlinear errors across the entire measurement range, generating compensated current data.

6. The method according to claim 1, characterized in that, In S600, the step of determining whether the vehicle has entered a stable sleep state based on the vehicle status signal and the compensated current data, and if it has entered a stable sleep state, comparing the compensated current data with a preset threshold to generate a leakage current determination result, includes: S610, based on the vehicle status signal, identify changes in the vehicle ignition switch status, engine speed and door open / close status, and determine whether the vehicle is currently in a wake-up state, a pre-dormant state, a dormant state or a driving state. S620, displays the compensated current data in real time, generates a dynamic curve of current changing with time, and marks each plateau period in the current decrease process; S630, when the vehicle is detected to have entered a stable sleep state, the current compensated current data is compared with the preset sleep current threshold. If the current compensated current data is greater than the preset sleep current threshold, a leakage current exceeding the standard judgment result is generated. S640, while maintaining the uninterrupted power detection path, removes the fuses of the suspected branches one by one, records and displays the current change before and after removing each fuse, identifies the branch with the largest current change as the main leakage branch, and generates leakage branch location information.

7. The method according to claim 6, characterized in that, In S700, the step of outputting a detection report based on the leakage current determination result includes: S710, integrate the compensated current data, the leakage current determination result, the current operating condition of the vehicle and the leakage current branch location information into a detection report; S720 presents the test report in the form of a chart through the display and interaction unit. The chart includes a curve of current change over time, a comparison chart of current changes in each branch, and a conclusion on leakage current determination.

8. A vehicle uninterruptible power leakage current detection system, characterized in that, include: At least one processor; At least one memory for storing at least one program; When the at least one program is executed by the at least one processor, the at least one processor performs the method as described in any one of claims 1 to 7.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 1 to 7.

10. A vehicle uninterruptible power leakage current detection device, characterized in that, include: A dual-path uninterruptible power supply module, comprising a parallel-to-serial wiring harness and an OBD power supply wiring harness, wherein the parallel-to-serial wiring harness comprises a battery terminal clamp and a wiring harness terminal clamp, and the OBD power supply wiring harness comprises a connector that matches the vehicle's OBD interface. A high-precision bidirectional current detection module includes a DC shunt, a differential amplifier, and a microcontroller unit. The DC shunt is connected in series in the detection circuit. The input terminal of the differential amplifier is connected to both ends of the DC shunt, and the output terminal of the differential amplifier is connected to the input terminal of the microcontroller unit. The intelligent control and data processing module includes a working condition identification unit and a display and interaction unit. The working condition identification unit acquires vehicle status signals through a CAN bus or hard-wired signals, and the display and interaction unit is used to output sleep guidance commands and detection reports.

Images