Method and system for monitoring abnormal disconnection condition of high-voltage relay of electric vehicle

Abstract

The invention discloses a method for monitoring an abnormal disconnection condition of a high-voltage relay of an electric vehicle, the method at least comprising the following operations: obtaining real-time monitoring data of the vehicle, the real-time monitoring data at least comprising a motor controller voltage and a motor speed (S1); and preliminarily determining an abnormal disconnection condition of the high-voltage relay according to the motor controller voltage and the motor speed (S2). The invention further discloses a system for monitoring the abnormal disconnection condition of the high-voltage relay of the electric vehicle and a computer program product. According to some exemplary embodiments of the invention, real-time monitoring can be realized, and the performance stability and driving safety of the electric vehicle can be improved.

Description

Technical Field

[0001] This invention relates to the field of vehicles, and particularly to the field of electric vehicles. Background Technology

[0002] People have increasingly higher performance requirements for electric vehicles, and a stable power supply is a crucial factor in demonstrating the superior performance of electric vehicles. The drive motor of an electric vehicle is connected to the power battery via a high-voltage circuit. The high-voltage relay, which controls the power supply, is a key electrical component of this circuit. An abnormal disconnection of the high-voltage relay will directly lead to a power interruption. Therefore, it is crucial to be aware of situations where an electric vehicle loses power due to an unexpected disconnection of the high-voltage relay as soon as possible. This allows for prompt repair and maintenance recommendations and also contributes to suggestions for manufacturing improvements for related models. However, current technology generally relies on user self-judgment and proactive reporting of unexpected high-voltage relay disconnections, which often results in missed reports and delays, making it difficult for automakers to promptly grasp and analyze the performance of electric vehicles.

[0003] Therefore, it is desirable to provide a method and system that can monitor the abnormal disconnection of high-voltage relays in electric vehicles in real time, thereby assisting automakers in timely screening of unexpected disconnection of high-voltage relays, providing customers with the necessary technical support at the first opportunity, and continuously improving vehicle performance stability and driving safety. Summary of the Invention

[0004] In order to overcome one of the above-mentioned disadvantages and / or other possible disadvantages in the prior art not mentioned herein, the object of the present invention is to provide a method and system for monitoring the abnormal disconnection of a high-voltage relay in an electric vehicle.

[0005] According to one aspect of the present invention, a method for monitoring the abnormal disconnection of a high-voltage relay in an electric vehicle is provided, the method comprising at least the following operations: S1 obtaining real-time monitoring data of the vehicle, the real-time monitoring data including at least motor controller voltage and motor speed; and S2 preliminarily determining the abnormal disconnection of the high-voltage relay based on the motor controller voltage and motor speed.

[0006] According to an optional embodiment of the present invention, in operation S2, when the voltage of the motor controller is less than the voltage threshold and the motor speed is greater than the speed threshold, it is initially determined that the high-voltage relay is disconnected.

[0007] According to an optional embodiment of the present invention, a vehicle whose high-voltage relay is initially determined to be disconnected is designated as a pending vehicle, and the abnormal disconnection of the high-voltage relay of the pending vehicle is further determined by combining other real-time monitoring data.

[0008] According to an optional embodiment of the present invention, the high-voltage relay includes a positive main relay, a negative main relay, and a protection relay for connecting the power battery in a high-voltage circuit.

[0009] According to an optional embodiment of the present invention, the other real-time monitoring data further includes the vehicle's accelerator pedal information, gear information, error or alarm information, and / or ignition switch information.

[0010] According to an optional embodiment of the present invention, when the accelerator pedal is depressed and the vehicle's motor has no torque output, or when the vehicle's accelerator pedal is not depressed but high-voltage components report errors or alarm messages, the high-voltage relay of the vehicle to be determined is abnormally disconnected.

[0011] According to an optional embodiment of the present invention, when the ignition switch is off and the vehicle is shifted from drive to park, or when the ignition switch is on and the vehicle is shifted from park to drive, it is determined that the high-voltage relay of the vehicle to be determined is not abnormally disconnected.

[0012] According to an optional embodiment of the present invention, the system assists automakers in obtaining real-time monitoring data of the vehicle, so that automakers can monitor the abnormal disconnection of the vehicle's high-voltage relay in real time.

[0013] According to a second aspect of the present invention, a system for monitoring abnormal disconnection of a high-voltage relay in an electric vehicle is provided, comprising: an acquisition module 1 configured to acquire real-time monitoring data of the vehicle, the real-time monitoring data including at least a motor controller voltage and a motor speed; and a judgment module 2 configured to preliminarily determine the abnormal disconnection of the high-voltage relay based on the motor controller voltage and the motor speed.

[0014] According to a third aspect of the invention, a computer program product, such as a machine-readable storage medium, is provided, which includes or stores computer program instructions that, when run on a computer, are adapted to perform a method for monitoring abnormal disconnection of a high-voltage relay in an electric vehicle.

[0015] According to certain exemplary embodiments of the present invention, real-time monitoring is possible, thereby improving the performance stability and driving safety of electric vehicles. Attached Figure Description

[0016] The invention will now be described in more detail with reference to the accompanying drawings, which will provide a better understanding of its principles, features, and advantages. The drawings include:

[0017] Figure 1 A flowchart is shown of a method for monitoring abnormal disconnection of a high-voltage relay in an electric vehicle according to an exemplary embodiment of the present invention.

[0018] Figure 2 A schematic diagram of the communication link for a method of monitoring abnormal disconnection of a high-voltage relay in an electric vehicle according to an exemplary embodiment of the present invention is shown.

[0019] Figure 3 A schematic diagram of a system for monitoring abnormal disconnection of a high-voltage relay in an electric vehicle, and a vehicle having such a system, is shown, according to an exemplary embodiment of the present invention. Detailed Implementation

[0020] To make the technical problems to be solved, the technical solutions, and the beneficial technical effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and several exemplary embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of protection of this invention.

[0021] The vehicle described in this invention can be a small car or a large truck, and in particular, it can be an autonomous vehicle or driverless vehicle at Level 3 or above. The monitoring of abnormal disconnection of the high-voltage relay in this invention refers to the disconnection of the high-voltage relay caused by abnormal vehicle operation or at least some software or hardware malfunctions, especially disconnection beyond the driver's control.

[0022] Figure 1 A flowchart is shown of a method for monitoring abnormal disconnection of a high-voltage relay in an electric vehicle according to an exemplary embodiment of the present invention.

[0023] The method of the present invention for monitoring abnormal disconnection of the high-voltage relay of an electric vehicle includes at least operations S1 and S2.

[0024] In operation S1, real-time monitoring data of the vehicle is obtained. This real-time monitoring data includes at least the motor controller voltage and motor speed. According to relevant national standards, such as GB / T 32960.3-2016 (Technical Specification for Remote Service and Management System of Electric Vehicles), real-time monitoring data (RTM) mainly includes several categories such as battery system data (core monitoring item), motor and electronic control data, safety and fault data, charging system data, and vehicle operation data. Electric vehicles can communicate with the monitoring and maintenance platform of car manufacturers or governments through an on-board terminal (T-Box). Specifically, the on-board terminal (T-Box) follows standard-defined communication protocols and data formats, can compress and encrypt data, and upload it to a cloud server via 4G / 5G / Wi-Fi. The cloud server stores and analyzes the data and pushes it to the maintenance platform. Figure 2The diagram shows a communication link for a method of monitoring abnormal disconnection of a high-voltage relay in an electric vehicle according to an exemplary embodiment of the present invention.

[0025] Optionally, vehicle manufacturing or operating companies can build a vehicle enterprise monitoring and maintenance platform. In operation S1, real-time monitoring data can be obtained from this platform, which may include at least motor controller voltage and motor speed. Specifically, the monitoring and maintenance platform can periodically acquire motor controller voltage and motor speed using conventional methods. Furthermore, when the motor controller voltage is abnormal (e.g., >600V or <240V), or when the motor is overspeeding, a level three alarm may be triggered. Therefore, the monitoring and maintenance platform can also indirectly obtain information such as motor controller voltage and motor speed by parsing the alarm information.

[0026] In operation S2, the abnormal disconnection of the high-voltage relay is initially determined based on the motor controller voltage and motor speed. Vehicle drivers often attempt to restart the vehicle after it loses power. However, in some cases, the high-voltage relay disconnection is not caused by a hardware malfunction, and the same high-voltage relay disconnection may not recur shortly after restarting. Therefore, drivers easily overlook the high-voltage relay disconnection, leading to the problem remaining unaddressed for an extended period. This invention no longer relies on user judgment and proactive information reporting, but instead uses real-time monitoring data to promptly grasp and analyze the operating status and performance of electric vehicles.

[0027] Optionally, in operation S2, when the motor controller voltage is less than a voltage threshold and the motor speed is greater than a speed threshold, it is preliminarily determined that the high-voltage relay of the electric vehicle is disconnected. Specifically, the voltage threshold (e.g., 240V) and speed threshold (e.g., 600rpm) are preset values ​​and can be adjusted according to the specific model and brand of the vehicle. In particular, for specific models and brands of vehicles, the voltage and speed thresholds can be obtained in advance based on tests on sample vehicles. The sample vehicles can be internal test vehicles of the car manufacturer or vehicles sold after the sale, as long as they can be monitored by the monitoring and maintenance platform. Here, the abnormal disconnection of the high-voltage relay can be directly determined based solely on the two real-time monitoring data of the motor controller voltage and the motor speed. This is beneficial for timely detection of situations where the high-voltage relay disconnection causes the vehicle to lose power, and it is less likely to miss the report.

[0028] However, to improve the accuracy of the determination, further determination can be made after initially identifying the abnormal disconnection of the high-voltage relay based solely on the motor controller voltage and motor speed real-time monitoring data. Optionally, vehicles whose high-voltage relays are initially identified as disconnected are designated as pending vehicles, and the abnormal disconnection of the high-voltage relays in these pending vehicles is further determined by combining other real-time monitoring data. The on-board terminal (T-Box) of the electric vehicle reads signals from the CAN bus at a preset step frequency. The same real-time monitoring data (RTM) message (such as a vehicle data frame) may contain signals at different step frequencies. Considering the very slight deviation in the step frequency of signals from different CAN buses, it is advantageous to introduce more real-time monitoring data in addition to the motor controller voltage and motor speed to more accurately determine the abnormal disconnection of the high-voltage relays in electric vehicles. Optionally, other real-time monitoring data may include the vehicle's accelerator pedal information, gear position information, error or alarm information, and / or ignition switch information. Error or alarm information specifically refers to information related to critical high-voltage components, including the motor, battery, inverter, and DC / DC converter. Errors or malfunctions in critical high-voltage components directly affect vehicle driving safety, often requiring immediate stopping of the vehicle in a safe location and power disconnection for repair. Therefore, error or alarm information related to critical high-voltage components can also be used to determine abnormal disconnection of high-voltage relays.

[0029] Optionally, when the accelerator pedal is depressed and the vehicle's motor has no torque output, it is determined that the high-voltage relay of the vehicle under investigation has abnormally disconnected. In particular, this can be further confirmed by combining real-time monitoring data related to the vehicle shifting from drive (D) to neutral (N), the ignition switch shifting from ON to ACC, the gradual decrease in vehicle speed and motor speed, the gradual decrease in inverter voltage, and the DC / DC converter being in OFF mode.

[0030] Optionally, when a high-voltage component reports an error or alarm, especially when an error or level 3 alarm related to a critical high-voltage component is reported, the high-voltage relay of the vehicle to be determined is disconnected. For example, in scenario 1: the ignition switch is in the ON position, the vehicle speed is zero, and the accelerator pedal is not depressed, but the motor speed increases rapidly, the inverter temperature also rises rapidly, and the DC / DC converter enters the LOCKED mode. Combining this real-time monitoring data, it is easy to know that the vehicle has a control logic error and the motor control system has malfunctioned. Further, it can be determined that the high-voltage relay of the vehicle has indeed disconnected, causing the electric vehicle to lose power. In scenario 2: the vehicle shifts from drive (D) to neutral (N), the vehicle speed and motor speed gradually decrease accordingly, the inverter voltage drops rapidly, and the DC / DC converter is in an abnormal state. For example, the DC / DC converter frequently switches between low-voltage high-demand (LHDM) mode, buck mode, and off mode. Combining this real-time monitoring data, it is easy to know that the DC / DC converter is in an abnormal state and triggers an alarm, causing a chain reaction. Further, it can be determined that the high-voltage relay of the vehicle has indeed abnormally disconnected, causing the vehicle to lose power.

[0031] Optionally, when the ignition switch is off and the vehicle is shifted from drive to park, or when the ignition switch is on and the vehicle is shifted from park to drive, it is determined that the high-voltage relay of the vehicle in question is not abnormally disconnected. Here, "on" means the ignition switch is in the ON position, and "off" means the ignition switch is in the ACC or OFF position. During normal power-on / start or power-off operation of an electric vehicle, it may experience an intermediate state where the motor controller voltage is lower than the threshold voltage and the motor speed is higher than the threshold speed. Combining the ignition switch information and gear position information mentioned above can avoid misjudging an abnormal disconnection of the high-voltage relay. For example, when the ignition switch is switched from the ON position to the ACC position, and the electric vehicle is simultaneously switched from the N position to the P position, with the accelerator pedal not depressed, the vehicle speed and motor speed gradually decrease accordingly, and the inverter voltage and voltage gradually decrease. When the DC / DC converter normally switches to the OFF mode, it is easy to know that the electric vehicle has completed the normal parking and power-off process, and it can be further determined that the high-voltage relay of the vehicle in question is not abnormally disconnected.

[0032] Additionally, when the monitoring and maintenance platform determines that the high-voltage relay has abnormally disconnected, causing the vehicle to lose power, it can promptly notify the user. The user can be the monitoring and maintenance personnel of the relevant car manufacturer or government, or the R&D engineer of the car manufacturer. This allows relevant engineering technicians to quickly grasp the vehicle's operating status, especially the situation of the vehicle losing power and its cause. This enables them to provide suggestions for vehicle maintenance and repair, and further, to provide improvement suggestions for the production and manufacturing of relevant models or brands of vehicles. Ultimately, this helps to improve the performance stability and driving safety of electric vehicles.

[0033] Optionally, based on the structural characteristics of high-voltage circuits in electric vehicles, the high-voltage relay of the present invention includes a positive main relay, a negative main relay, and a protection relay in the high-voltage circuit for connecting the power battery and the motor controller.

[0034] Figure 3 A schematic diagram of a system for monitoring abnormal disconnection of a high-voltage relay in an electric vehicle, according to an exemplary embodiment of the present invention, is shown.

[0035] The system for monitoring abnormal disconnection of high-voltage relays in electric vehicles according to the present invention includes:

[0036] Acquisition module 1 is configured to acquire real-time monitoring data of the vehicle, the real-time monitoring data including at least the motor controller voltage and motor speed; and

[0037] The judgment module 2 is configured to preliminarily determine the abnormal disconnection status of the high-voltage relay based on the motor controller voltage and the motor speed.

[0038] Optionally, the acquisition module 1 and the judgment module 2 are configured for use in the corresponding monitoring and maintenance platform, especially the monitoring and maintenance platform of car manufacturers, so that car manufacturers can keep track of the abnormal disconnection of the high-voltage relays of vehicles in real time.

[0039] Optionally, the acquisition module 1 can periodically or triggeredly acquire real-time monitoring data in accordance with the communication protocols and data formats defined by relevant standards.

[0040] The present invention also discloses a computer program product, such as a machine-readable storage medium, which includes or stores computer program instructions, said computer program being adapted, when run on a computer, to perform the method of the present invention for monitoring abnormal disconnection of a high-voltage relay in an electric vehicle.

[0041] Although specific embodiments have been described above, these embodiments are not intended to limit the scope of the invention, even when only a single embodiment is described with respect to a particular feature. The feature examples provided in this disclosure are intended to be illustrative and not limiting, unless explicitly stated otherwise. In practice, multiple features may be combined with each other as needed and where technically feasible. Various substitutions, alterations, and modifications are conceived without departing from the spirit and scope of the invention.

Claims

1. A method for monitoring abnormal disconnection of a high-voltage relay in an electric vehicle, the method comprising at least the following operations: S1) Obtain real-time monitoring data of the vehicle, wherein the real-time monitoring data includes at least the motor controller voltage and motor speed; and S2) Based on the motor controller voltage and motor speed, the abnormal disconnection status of the high-voltage relay is initially determined.

2. The method for monitoring the abnormal disconnection of high-voltage relays in electric vehicles according to claim 1, characterized in that, In operation S2), when the voltage of the motor controller is less than the voltage threshold and the motor speed is greater than the speed threshold, it is initially determined that the high-voltage relay is disconnected.

3. The method for monitoring the abnormal disconnection of the high-voltage relay in an electric vehicle according to claim 2, characterized in that, Vehicles whose high-voltage relays are initially determined to be disconnected are designated as pending vehicles. Further analysis is then conducted using other real-time monitoring data to determine the abnormal disconnection of the high-voltage relays in these pending vehicles.

4. The method for monitoring the abnormal disconnection of a high-voltage relay in an electric vehicle according to any one of claims 1-3, characterized in that, The high-voltage relay includes a positive main relay, a negative main relay, and a protection relay for connecting the high-voltage circuit of the power battery.

5. The method for monitoring the abnormal disconnection of the high-voltage relay in an electric vehicle according to claim 3 or 4, characterized in that, Other real-time monitoring data includes the vehicle's accelerator pedal information, gear information, error or alarm information, and / or ignition switch information.

6. The method for monitoring the abnormal disconnection of a high-voltage relay in an electric vehicle according to any one of claims 2-5, characterized in that, When the accelerator pedal is depressed and the vehicle's motor has no torque output, or, When the high-voltage components of the vehicle display error or alarm messages, Then it is determined that the high-voltage relay of the vehicle to be determined is abnormally disconnected.

7. The method for monitoring the abnormal disconnection of a high-voltage relay in an electric vehicle according to any one of claims 3-6, characterized in that, When the ignition switch is turned off and the vehicle is shifted from drive to park, or, When the ignition switch is turned on and the vehicle is shifted from park to drive, Then it is determined that the high-voltage relay of the vehicle to be determined is not abnormally disconnected.

8. The method for monitoring the abnormal disconnection of a high-voltage relay in an electric vehicle according to any one of claims 1-7, characterized in that, This assists automakers in obtaining real-time monitoring data of the vehicles, enabling them to monitor the abnormal disconnection of the high-voltage relays in real time.

9. A system for monitoring abnormal disconnection of a high-voltage relay in an electric vehicle, comprising: The acquisition module (1) is configured to acquire real-time monitoring data of the vehicle, the real-time monitoring data including at least the motor controller voltage and the motor speed; and The judgment module (2) is configured to preliminarily determine the abnormal disconnection of the high-voltage relay based on the voltage of the motor controller and the motor speed.

10. A computer program product, such as a machine-readable storage medium, comprising or storing computer program instructions, said computer program, when run on a computer, being adapted to perform the method for monitoring abnormal disconnection of a high-voltage relay in an electric vehicle according to any one of claims 1-8.

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