Fast charging relay sticking diagnosis method, device, equipment and storage medium

Abstract

The application discloses a fast-charging relay sticking diagnosis method, device and equipment and a storage medium, relates to the technical field of vehicle detection, and comprises the following steps: according to the state of a power battery pack, the working state of a charging pile, the state of a motor and the power supply state of a fast-charging relay, a sticking diagnosis precondition is judged; based on the judgment result and when the sticking diagnosis precondition is met, fast-charging relay sticking diagnosis in a charging end state and fast-charging relay sticking diagnosis in a driving state are performed; wherein, in a specific high-voltage architecture, the fast-charging relay is arranged outside the power battery pack. The application can realize accurate control and diagnosis of fast-charging relay sticking.

Description

Technical Field

[0001] This application relates to the field of vehicle testing technology, specifically to a method, device, equipment, and storage medium for diagnosing fast charging relay adhesion. Background Technology

[0002] In new energy vehicles, the fast-charging relay is the core safety switch in the DC fast-charging circuit. It is responsible for reliably connecting during DC charging and completely cutting off the large current of up to hundreds of amperes when charging ends or an abnormality occurs. In traditional solutions, the fast-charging relay (which includes a positive fast-charging relay and a negative fast-charging relay, generally designated K5 and K6 in automotive circuits) is usually located inside the power battery pack BDU (Battery Distribution Unit). The voltage before and after the fast-charging relay is collected by the high-voltage sensor built into the BMS (Battery Management System) to determine whether the fast-charging relay has become stuck.

[0003] Real-time and reliable diagnosis of the operating status of fast-charging relays is crucial because the arcing generated by high current can easily cause the relay contacts to stick together, making them physically unable to disconnect. Once this fault occurs, the high-voltage system of the vehicle will not be able to safely disconnect after charging, potentially leading to serious risks of leakage, short circuits, or even electric shock. Therefore, effectively diagnosing the sticking state of fast-charging relays is a pressing issue that needs to be addressed. Summary of the Invention

[0004] This application provides a method, apparatus, device, and storage medium for diagnosing fast charging relay adhesion, which can achieve precise control and diagnosis of fast charging relay adhesion.

[0005] In a first aspect, embodiments of this application provide a method for diagnosing fast-charging relay adhesion, used to diagnose the adhesion state of fast-charging relays in a specific high-voltage architecture. The fast-charging relay adhesion diagnosis method includes: Based on the charging status of the power battery pack, the working status of the charging pile, the status of the motor, and the power supply status of the fast charging relay, the preconditions for adhesion diagnosis are determined. Based on the judgment results and when the preconditions for adhesion diagnosis are met, fast charging relay adhesion diagnosis is performed in the charging end state and in the driving state. In the specific high-voltage architecture, the fast-charging relay is located outside the power battery pack.

[0006] In conjunction with the first aspect, in one embodiment, in the specific high-voltage architecture, the power supply terminal of the fast-charging relay is controlled by the BMS, and the control terminal of the fast-charging relay is controlled by the PDU or CCU.

[0007] In conjunction with the first aspect, in one implementation method, When the BMS does not detect a power battery pack charging prohibition fault and supplies power to the fast charging relay, and the main relay inside the power battery pack is closed and in the charging allowed state, and the charging pile output current is less than the set current and the charging pile relay is open, then the preconditions for fast charging relay adhesion diagnosis are met under the charging end state.

[0008] In conjunction with the first aspect, in one implementation method, the diagnosis of fast charging relay sticking in the charging completion state specifically includes: The PDU controls both the positive and negative fast-charging relays to disconnect simultaneously, waits for a preset time, then acquires the voltage flag and makes a judgment: If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that both the positive and negative fast charging relays are stuck together. If the voltage flag indicates that the voltage is normal, the positive fast charging relay is closed and the negative fast charging relay is opened to diagnose the negative fast charging relay sticking. Similarly, the positive fast charging relay is opened and the negative fast charging relay is closed to diagnose the positive fast charging relay sticking.

[0009] In conjunction with the first aspect, in one embodiment, the control of closing the positive fast charging relay and opening the negative fast charging relay to perform negative fast charging relay adhesion diagnosis, and the control of opening the positive fast charging relay and closing the negative fast charging relay to perform positive fast charging relay adhesion diagnosis, specifically include: The PDU controls the positive fast-charging relay to close and the negative fast-charging relay to open, waits for a preset time, acquires the voltage flag, and then determines the following: If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that the negative fast charging relay has stuck. If the voltage flag indicates that the voltage is normal, the negative fast charging relay is determined to be normal. Then, the PDU controls the positive fast charging relay to open and the negative fast charging relay to close. After waiting for a preset time, the voltage flag is obtained. If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, the positive fast charging relay is determined to be stuck. If the voltage flag indicates that the voltage is normal, the positive fast charging relay is determined to be normal.

[0010] In conjunction with the first aspect, in one implementation method, When the BMS determines that the motor speed is within the preset speed range, the fast charging relay is in the power supply state, and the PDU determines that a DC charge has been completed in the current power-on cycle, the preconditions for fast charging relay adhesion diagnosis in driving mode are met.

[0011] In conjunction with the first aspect, in one implementation method, the diagnosis of fast charging relay sticking while the vehicle is in motion specifically includes: The PDU controls the positive fast-charging relay to close and the negative fast-charging relay to open, waits for a preset time, acquires the voltage flag, and then determines the following: If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that the negative fast charging relay has stuck. If the voltage flag indicates that the voltage is normal, the negative fast charging relay is determined to be normal. Then, the PDU controls the positive fast charging relay to open and the negative fast charging relay to close. After waiting for a preset time, the voltage flag is obtained. If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, the positive fast charging relay is determined to be stuck. If the voltage flag indicates that the voltage is normal, the positive fast charging relay is determined to be normal.

[0012] Secondly, embodiments of this application provide a fast charging relay adhesion diagnostic device, the fast charging relay adhesion diagnostic device comprising: The judgment module is used to determine the preconditions for adhesion diagnosis based on the charging status of the power battery pack, the working status of the charging pile, the motor status, and the power supply status of the fast charging relay. The execution module is used to perform fast charging relay adhesion diagnosis in the charging end state and fast charging relay adhesion diagnosis in the driving state based on the judgment result and when the adhesion diagnosis preconditions are met. In the specific high-voltage architecture, the fast-charging relay is located outside the power battery pack.

[0013] Thirdly, embodiments of this application provide a fast charging relay adhesion diagnostic device, which includes a processor, a memory, and a fast charging relay adhesion diagnostic program stored in the memory and executable by the processor. When the fast charging relay adhesion diagnostic program is executed by the processor, it implements the steps of the fast charging relay adhesion diagnostic method described above.

[0014] Fourthly, embodiments of this application provide a computer-readable storage medium storing a fast-charging relay adhesion diagnostic program, wherein when the fast-charging relay adhesion diagnostic program is executed by a processor, it implements the steps of the fast-charging relay adhesion diagnostic method described above.

[0015] The beneficial effects of the technical solutions provided in this application include: (1) Convenience of maintenance and cost optimization: By structurally separating the fast charging relay and the power battery pack, the operation difficulty and time cost during after-sales maintenance are greatly reduced, making maintenance and replacement easier and thus effectively reducing maintenance expenses throughout the entire life cycle; (2) Enhanced functional safety and system redundancy: The relay control strategy with strong functional safety is distributed and deployed in multiple controllers. The BMS is responsible for power supply management and the PDU is responsible for control execution. The system redundancy is enhanced through the dual control coordination mechanism, which further strengthens the functional safety and reliability of the high-voltage circuit. (3) Enhanced intelligent detection and system integration: By comprehensively analyzing multiple working conditions and diagnostic windows, real-time monitoring and intelligent diagnosis of the fast charging relay adhesion status are realized, which not only improves the flexibility and accuracy of fault detection, but also enhances the configurability and integration of the overall architecture. Attached Figure Description

[0016] Figure 1 This is a flowchart illustrating the fast-charging relay adhesion diagnosis method of this application; Figure 2 This is a schematic diagram of a specific high-voltage architecture for this application; Figure 3 A flowchart illustrating the diagnosis of fast charging relay sticking in the charging completed state; Figure 4 This is a flowchart illustrating the diagnostic process for fast charging relay sticking while the vehicle is in motion. Figure 5 This is a schematic diagram of the functional modules of the fast charging relay adhesion diagnostic device of this application; Figure 6 This is a schematic diagram of the hardware structure of the fast charging relay adhesion diagnostic device of this application. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present application.

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0019] In the first aspect, embodiments of this application provide a fast charging relay adhesion diagnosis method, which detaches the fast charging relay from the power battery pack and places it in a part that is easily replaced after-sales, such as an OBC (On Board Charger), and designs an adhesion diagnosis strategy integrated in a domain controller to achieve precise control and diagnosis of fast charging relay adhesion.

[0020] In one embodiment, reference is made to Figure 1 , Figure 1 This is a flowchart illustrating the fast-charging relay adhesion diagnosis method of this application. Figure 1 As shown, the diagnostic methods for fast charging relay adhesion include: S1: Based on the charging status of the power battery pack, the working status of the charging pile, the status of the motor, and the power supply status of the fast charging relay, determine the prerequisites for adhesion diagnosis. S2: Based on the judgment result and when the preconditions for adhesion diagnosis are met, fast charging relay adhesion diagnosis is performed in the charging end state and in the driving state; wherein, in the specific high voltage architecture, the fast charging relay is arranged outside the power battery pack.

[0021] For details, see Figure 2 The diagram shown is a design schematic of a specific high-voltage architecture in this application. The positive and negative fast-charging relays are physically removed from the power battery pack. In this specific high-voltage architecture, the power supply terminal of the fast-charging relay is controlled by the BMS, increasing functional safety design redundancy. The control terminal of the fast-charging relay is controlled by the PDU (Power Distribution Unit) or CCU (Centralized Control Unit). Furthermore, a VDC (Voltage Detection Module) is added to the OBC (On Board Charger) to measure whether there is a high voltage greater than 60V on the charging port side. Figure 2 In this context, MCU stands for Motor Control Unit.

[0022] Furthermore, in one embodiment, when the BMS does not detect a charging prohibition fault in the power battery pack and supplies power to the fast charging relay, and the main relay inside the power battery pack is closed and in a charging-allowed state, and the charging pile output current is less than the set current and the charging pile relay is open, then the preconditions for fast charging relay adhesion diagnosis are met under the charging end state.

[0023] Specifically, when both conditions A and B are met, the fast-charging relay sticking diagnosis process is initiated in the charging-completed state. Condition A is that the BMS does not detect a charging prohibition fault at the power battery pack end and supplies power to the fast-charging relay, with the main relay inside the power battery pack closed and in a charging-allowed state; Condition B is that when the output current at the charging pile end is less than 1A, charging stops and the charging pile end disconnects.

[0024] Furthermore, in one embodiment, the diagnosis of fast charging relay sticking in the charging completed state specifically includes: The PDU controls both the positive and negative fast-charging relays to disconnect simultaneously, waits for a preset time, then acquires the voltage flag and makes a judgment: If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that both the positive and negative fast charging relays are stuck together. If the voltage flag indicates that the voltage is normal, the positive fast charging relay is closed and the negative fast charging relay is opened to diagnose the negative fast charging relay sticking. Similarly, the positive fast charging relay is opened and the negative fast charging relay is closed to diagnose the positive fast charging relay sticking.

[0025] Specifically, the PDU controls the positive and negative fast charging relays to disconnect simultaneously, waits for a preset time, and then obtains the voltage flag. If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that both the positive and negative fast charging relays are stuck together. If the voltage flag indicates that the voltage is normal, the PDU controls the positive fast charging relay to close and the negative fast charging relay to disconnect to diagnose the negative fast charging relay sticking together. The PDU also controls the positive fast charging relay to disconnect and the negative fast charging relay to close to diagnose the positive fast charging relay sticking together.

[0026] Furthermore, in one embodiment, controlling the positive fast charging relay to close and the negative fast charging relay to open to perform negative fast charging relay adhesion diagnosis, and controlling the positive fast charging relay to open and the negative fast charging relay to close to perform positive fast charging relay adhesion diagnosis, specifically includes: The PDU controls the positive fast-charging relay to close and the negative fast-charging relay to open, waits for a preset time, acquires the voltage flag, and then determines the following: If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that the negative fast charging relay has stuck. If the voltage flag indicates that the voltage is normal, the negative fast charging relay is determined to be normal. Then, the PDU controls the positive fast charging relay to open and the negative fast charging relay to close. After waiting for a preset time, the voltage flag is obtained. If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, the positive fast charging relay is determined to be stuck. If the voltage flag indicates that the voltage is normal, the positive fast charging relay is determined to be normal.

[0027] Specifically, the PDU controls the positive fast charging relay to close and the negative fast charging relay to open. After waiting for a preset time, it obtains the voltage flag. If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that the negative fast charging relay is stuck. If the voltage flag indicates that the voltage is normal, it is determined that the negative fast charging relay is normal. After the diagnosis of the negative fast charging relay is completed, the PDU controls the positive fast charging relay to open and the negative fast charging relay to close. After waiting for a preset time, it obtains the voltage flag. If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that the positive fast charging relay is stuck. If the voltage flag indicates that the voltage is normal, it is determined that the positive fast charging relay is normal.

[0028] The following combination Figure 3This application provides a detailed explanation of the fast charging relay adhesion diagnosis method in the charging completion state.

[0029] For the diagnosis of fast charging relay sticking in the charging end state, the diagnostic window of the positive fast charging relay closure and the negative fast charging relay is designed after DC (Direct Charger) charging is completed. The input signal of the monitoring logic is whether the DC charging port voltage is greater than 60V (Flag Voltage=1 is greater than 60V, Flag Voltage=0 is less than 60V).

[0030] The BMS did not detect a charging prohibition fault at the power battery pack end and supplied power to the fast charging relay. The main relay inside the power battery pack was closed and in the charging enabled state. When the output current at the charging pile end was less than 1A, charging stopped and the charging pile end was disconnected. At this time, the vehicle end entered the fast charging relay adhesion diagnosis.

[0031] First, the PDU requests that both the positive and negative fast charging relays simultaneously disconnect. After waiting for a preset time, it acquires and judges the voltage flag (Flag Voltage). If Flag Voltage = 1 (meaning the voltage flag indicates an over-limit voltage) and remains so for the set duration, it determines that both the positive and negative fast charging relays are stuck. Then, the fast charging relay sticking diagnosis ends in the charging-completed state. If Flag Voltage = 0 (meaning the voltage flag indicates normal voltage), it proceeds to the next step. The PDU requests that the positive fast charging relay close, while the negative fast charging relay remains disconnected. After waiting for a preset time, it acquires and judges the voltage flag (Flag Voltage). If Flag Voltage = 1 and remains so for the set duration, it determines that the negative fast charging relay is stuck. If Flag Voltage = 0, it determines that the negative fast charging relay is normal. After judging the negative fast charging relay, it proceeds to the next step. The PDU controls the positive fast charging relay to disconnect and the negative fast charging relay to close. After waiting for a preset time, it acquires and judges the voltage flag (Flag Voltage). If Flag Voltage = 1 and remains so for the set duration, it determines that the positive fast charging relay is stuck. If Flag Voltage = 0, it determines that the negative fast charging relay is normal. If Voltage=0, the positive fast charging relay is considered normal. After the adhesion diagnosis is completed, the PDU controls both the positive and negative fast charging relays to disconnect simultaneously.

[0032] Furthermore, in one embodiment, when the BMS determines that the motor speed is within a preset speed range, the fast charging relay is in a power-on state, and the PDU determines that a DC charge has been completed within the current power-on cycle, the preconditions for fast charging relay adhesion diagnosis under driving conditions are met.

[0033] For diagnosing fast charging relay sticking while driving, the specific steps include: The PDU controls the positive fast-charging relay to close and the negative fast-charging relay to open, waits for a preset time, acquires the voltage flag, and then determines the following: If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that the negative fast charging relay has stuck. If the voltage flag indicates that the voltage is normal, the negative fast charging relay is determined to be normal. Then, the PDU controls the positive fast charging relay to open and the negative fast charging relay to close. After waiting for a preset time, the voltage flag is obtained. If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, the positive fast charging relay is determined to be stuck. If the voltage flag indicates that the voltage is normal, the positive fast charging relay is determined to be normal.

[0034] Specifically, the PDU controls the positive fast charging relay to close and the negative fast charging relay to open. After waiting for a preset time, it obtains the voltage flag. If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that the negative fast charging relay is stuck. If the voltage flag indicates that the voltage is normal, it is determined that the negative fast charging relay is normal. After the diagnosis of the negative fast charging relay is completed, the PDU controls the positive fast charging relay to open and the negative fast charging relay to close. After waiting for a preset time, it obtains the voltage flag. If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that the positive fast charging relay is stuck. If the voltage flag indicates that the voltage is normal, it is determined that the positive fast charging relay is normal.

[0035] The following combination Figure 4 This application provides a detailed explanation of the diagnosis of fast charging relay adhesion while the vehicle is in motion.

[0036] Under non-charging conditions, the positive and negative fast charging relays must be in the open state to ensure high voltage safety. This application provides a fast charging relay adhesion diagnosis under driving conditions to perform single fast charging relay adhesion diagnosis.

[0037] When both the first and second conditions are met, the fast charging relay adhesion diagnosis process under driving conditions is executed to diagnose adhesion for a single fast charging relay.

[0038] The first condition is that the BMS determines the motor speed is within a preset speed range. This condition locks the vehicle speed range, such as within a low-speed range of 20kph to 30kph. If this condition is met, the BMS supplies power to both the positive and negative fast-charging relays. The second condition is that the PDU determines that one DC charge has been completed within the current power-on cycle. The purpose of this condition is to reduce the frequency of diagnostics and extend the lifespan of the fast-charging relays.

[0039] If both the first and second conditions are met, the fast charging relay adhesion diagnosis process in driving mode will be executed; otherwise, it will exit.

[0040] The specific diagnostic process for fast charging relay sticking while the vehicle is in motion is as follows: The PDU controls the positive fast charging relay to close, while the negative fast charging relay is in the open state. After waiting for a preset time, the voltage flag bit (Flag Voltage) is obtained and judged. If Flag Voltage = 1 and continues for the set duration, the negative fast charging relay is determined to be sticking; if Flag Voltage = 0, the negative fast charging relay is determined to be normal. After judging the negative fast charging relay, the next step is to control the positive fast charging relay to open and the negative fast charging relay to close. After waiting for a preset time, the voltage flag bit (Flag Voltage) is obtained and judged. If Flag Voltage = 1 and continues for the set duration, the positive fast charging relay is determined to be sticking; if Flag Voltage = 0, the positive fast charging relay is determined to be normal. After the sticking diagnosis is completed, the PDU controls both the positive and negative fast charging relays to open simultaneously.

[0041] The fast-charging relay adhesion diagnosis method of this application offers several advantages: Improved maintenance convenience and cost optimization: By structurally separating the fast-charging relay from the power battery pack, the operational difficulty and time cost during after-sales maintenance are significantly reduced, facilitating maintenance and replacement, thereby effectively reducing maintenance expenses throughout the entire lifecycle. Enhanced functional safety and system redundancy: The relay control strategy, which is strongly related to functional safety, is distributed across multiple controllers. The BMS is responsible for power supply management, and the PDU is responsible for control execution. This dual-control collaborative mechanism enhances system redundancy and further strengthens the functional safety and reliability of the high-voltage circuit. Enhanced intelligent detection and system integration: By comprehensively analyzing multiple operating conditions and diagnostic windows, real-time monitoring and intelligent diagnosis of the fast-charging relay adhesion status are achieved. This not only improves the flexibility and accuracy of fault detection but also enhances the configurability and integration of the overall architecture.

[0042] Secondly, embodiments of this application also provide a fast charging relay adhesion diagnostic device.

[0043] In one embodiment, reference is made to Figure 5 , Figure 5 This is a schematic diagram of the functional modules of the fast-charging relay adhesion diagnostic device of this application. Figure 5 As shown, the fast charging relay adhesion diagnostic device includes: a judgment module and an execution module.

[0044] The judgment module is used to determine the preconditions for adhesion diagnosis based on the charging status of the power battery pack, the working status of the charging pile, the motor status, and the power supply status of the fast charging relay; the execution module is used to perform fast charging relay adhesion diagnosis in the charging end state and fast charging relay adhesion diagnosis in the driving state based on the judgment results and when the adhesion diagnosis preconditions are met; wherein, in the specific high voltage architecture, the fast charging relay is arranged outside the power battery pack.

[0045] Thirdly, embodiments of this application provide a fast charging relay adhesion diagnostic device, which can be a device with data processing capabilities such as a personal computer (PC), a laptop, or a server.

[0046] Reference Figure 6 , Figure 6 This is a schematic diagram of the hardware structure of the fast charging relay adhesion diagnostic device involved in the embodiments of this application. In the embodiments of this application, the fast charging relay adhesion diagnostic device may include a processor, a memory, a communication interface, and a communication bus.

[0047] The communication bus can be of any type and is used to interconnect the processor, memory, and communication interface.

[0048] The communication interface includes input / output (I / O) interfaces, physical interfaces, and logical interfaces used for interconnecting internal components of the fast-charging relay adhesion diagnostic device, as well as interfaces used for interconnecting the device with other devices (such as other computing devices or user equipment). Physical interfaces can be Ethernet interfaces, fiber optic interfaces, ATM interfaces, etc.; user equipment can be displays, keyboards, etc.

[0049] Memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0050] The processor can be a general-purpose processor, which can call the fast-charging relay adhesion diagnosis program stored in the memory and execute the fast-charging relay adhesion diagnosis method provided in the embodiments of this application. For example, the general-purpose processor can be a central processing unit (CPU). The method executed when the fast-charging relay adhesion diagnosis program is called can be referred to in the various embodiments of the fast-charging relay adhesion diagnosis method of this application, and will not be repeated here.

[0051] Those skilled in the art will understand that Figure 6 The hardware structure shown does not constitute a limitation of this application and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0052] Fourthly, embodiments of this application also provide a computer-readable storage medium.

[0053] The present application provides a computer-readable storage medium storing a fast charging relay adhesion diagnostic program, wherein when the fast charging relay adhesion diagnostic program is executed by a processor, it implements the steps of the fast charging relay adhesion diagnostic method described above.

[0054] The method implemented when the fast charging relay adhesion diagnosis procedure is executed can be referred to in various embodiments of the fast charging relay adhesion diagnosis method of this application, and will not be repeated here.

[0055] The terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus. The terms "first," "second," and "third," etc., are used to distinguish different objects, etc., and do not indicate a sequence, nor do they limit "first," "second," and "third" to different types.

[0056] In the description of the embodiments of this application, terms such as "exemplary," "for example," or "for instance" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplary," "for example," or "for instance" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary," "for example," or "for instance" is intended to present the relevant concepts in a concrete manner.

[0057] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this application, "multiple" means two or more.

[0058] In some processes described in the embodiments of this application, multiple operations or steps are included in a specific order. However, it should be understood that these operations or steps may not be executed in the order they appear in the embodiments of this application, or they may be executed in parallel. The sequence number of the operation is only used to distinguish different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed sequentially or in parallel, and these operations or steps may be combined.

[0059] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of 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 this application, in essence, 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) as described above, and includes several instructions to cause a terminal device to execute the methods described in the various embodiments of this application.

[0060] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A method for diagnosing fast-charging relay adhesion, used to diagnose the adhesion status of fast-charging relays in a specific high-voltage architecture, characterized in that, The fast charging relay adhesion diagnosis method includes: Based on the charging status of the power battery pack, the working status of the charging pile, the status of the motor, and the power supply status of the fast charging relay, the preconditions for adhesion diagnosis are determined. Based on the judgment results and when the preconditions for adhesion diagnosis are met, fast charging relay adhesion diagnosis is performed in the charging end state and in the driving state. In the specific high-voltage architecture, the fast-charging relay is located outside the power battery pack.

2. The fast charging relay adhesion diagnosis method as described in claim 1, characterized in that, In the specific high-voltage architecture, the power supply terminal of the fast charging relay is controlled by the BMS, and the control terminal of the fast charging relay is controlled by the PDU or CCU.

3. The fast charging relay adhesion diagnosis method as described in claim 2, characterized in that: When the BMS does not detect a power battery pack charging prohibition fault and supplies power to the fast charging relay, and the main relay inside the power battery pack is closed and in the charging allowed state, and the charging pile output current is less than the set current and the charging pile relay is open, then the preconditions for fast charging relay adhesion diagnosis are met under the charging end state.

4. The fast charging relay adhesion diagnosis method as described in claim 2, characterized in that, For diagnosing fast charging relay sticking after charging is complete, the specific steps include: The PDU controls both the positive and negative fast-charging relays to disconnect simultaneously, waits for a preset time, then acquires the voltage flag and makes a judgment: If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that both the positive and negative fast charging relays are stuck together. If the voltage flag indicates that the voltage is normal, the positive fast charging relay is closed and the negative fast charging relay is opened to diagnose the negative fast charging relay sticking. Similarly, the positive fast charging relay is opened and the negative fast charging relay is closed to diagnose the positive fast charging relay sticking.

5. The fast charging relay adhesion diagnosis method as described in claim 4, characterized in that, The method of controlling the positive fast charging relay to close and the negative fast charging relay to open to diagnose negative fast charging relay adhesion, and controlling the positive fast charging relay to open and the negative fast charging relay to close to diagnose positive fast charging relay adhesion, specifically includes: The PDU controls the positive fast-charging relay to close and the negative fast-charging relay to open, waits for a preset time, acquires the voltage flag, and then determines the following: If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that the negative fast charging relay has stuck. If the voltage flag indicates that the voltage is normal, the negative fast charging relay is determined to be normal. Then, the PDU controls the positive fast charging relay to open and the negative fast charging relay to close. After waiting for a preset time, the voltage flag is obtained. If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, the positive fast charging relay is determined to be stuck. If the voltage flag indicates that the voltage is normal, the positive fast charging relay is determined to be normal.

6. The fast charging relay adhesion diagnosis method as described in claim 2, characterized in that: When the BMS determines that the motor speed is within the preset speed range, the fast charging relay is in the power supply state, and the PDU determines that a DC charge has been completed in the current power-on cycle, the preconditions for fast charging relay adhesion diagnosis in driving mode are met.

7. The fast charging relay adhesion diagnosis method as described in claim 6, characterized in that, For diagnosing fast charging relay sticking while driving, the specific steps include: The PDU controls the positive fast-charging relay to close and the negative fast-charging relay to open, waits for a preset time, acquires the voltage flag, and then determines the following: If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, it is determined that the negative fast charging relay has stuck. If the voltage flag indicates that the voltage is normal, the negative fast charging relay is determined to be normal. Then, the PDU controls the positive fast charging relay to open and the negative fast charging relay to close. After waiting for a preset time, the voltage flag is obtained. If the voltage flag indicates that the voltage exceeds the limit and continues for the set duration, the positive fast charging relay is determined to be stuck. If the voltage flag indicates that the voltage is normal, the positive fast charging relay is determined to be normal.

8. A fast-charging relay adhesion diagnostic device, characterized in that, The fast charging relay adhesion diagnostic device includes: The judgment module is used to determine the preconditions for adhesion diagnosis based on the charging status of the power battery pack, the working status of the charging pile, the motor status, and the power supply status of the fast charging relay. The execution module is used to perform fast charging relay adhesion diagnosis in the charging end state and fast charging relay adhesion diagnosis in the driving state based on the judgment result and when the adhesion diagnosis preconditions are met. In the specific high-voltage architecture, the fast-charging relay is located outside the power battery pack.

9. A diagnostic device for fast-charging relay adhesion, characterized in that, The fast charging relay adhesion diagnostic device includes a processor, a memory, and a fast charging relay adhesion diagnostic program stored in the memory and executable by the processor, wherein when the fast charging relay adhesion diagnostic program is executed by the processor, it implements the steps of the fast charging relay adhesion diagnostic method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a fast-charging relay adhesion diagnostic program, wherein when the fast-charging relay adhesion diagnostic program is executed by a processor, it implements the steps of the fast-charging relay adhesion diagnostic method as described in any one of claims 1 to 7.

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