Insulation failure fault detection method and vehicle high-voltage system

Abstract

The invention provides an insulation failure fault detection method and a vehicle high-voltage system, and relates to the technical field of vehicle fault detection. The method comprises the steps of controlling a target contactor to be in a first state according to a to-be-detected object in a vehicle high-voltage system; wherein the to-be-detected object is any detection object in an input loop of a power battery, a power distribution loop of a high-voltage power distribution unit and at least one group of high-voltage parts; acquiring a first insulation detection value of the to-be-detected object detected by the insulation detection circuit in the preset detection period; according to the first insulation detection value and a preset fault threshold value, an insulation detection result is determined, and the insulation detection result is used for indicating whether the to-be-detected object has insulation abnormity or not. According to the invention, automatic detection and positioning of an insulation failure fault can be realized, and the troubleshooting efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of automotive fault detection technology, and more specifically, to a method for detecting insulation failure faults and a vehicle high-voltage system. Background Technology

[0002] Due to their high voltage and large current characteristics, new energy vehicles have high requirements for the insulation performance of their systems. Furthermore, the insulation status of each system must be monitored in real time to prevent injury to personnel and damage to the vehicle in the event of insulation failure.

[0003] In existing technology, by connecting all high-voltage components in the same circuit, when the vehicle experiences an insulation failure, since the location of the circuit fault cannot be directly determined, the vehicle will actively stop the operation of all high-voltage components and disconnect the high-voltage contactor of the circuit, thus reducing the high voltage of the vehicle.

[0004] However, because this method cannot directly determine the location of the circuit fault or narrow down the fault range, it can only shut down the circuit and measure the insulation of all high-voltage components one by one when a fault occurs, resulting in very low fault diagnosis efficiency. Summary of the Invention

[0005] The purpose of this application is to address the shortcomings of the prior art by providing an insulation failure fault detection method and a vehicle high-voltage system, so as to achieve automatic detection and location of insulation failure faults and improve fault diagnosis efficiency.

[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows: In a first aspect, embodiments of this application provide an insulation failure fault detection method applied to a vehicle controller connected to a vehicle high-voltage system. The vehicle high-voltage system includes: a power battery, a high-voltage power distribution unit, and at least one set of high-voltage components. The vehicle controller is connected to an insulation detection circuit, two input contactors, and at least one set of output contactors of the high-voltage power distribution unit. The two ends of the power battery are connected to the insulation detection circuit and the two input contactors, respectively. The two input contactors are connected to two output contactors in each set of output contactors via positive and negative wiring harnesses, respectively. Each set of output contactors connects to a set of high-voltage components to form a system. The method includes: According to the object to be tested in the vehicle high-voltage system, the target contactor is controlled to be in a first state; wherein, the object to be tested is any one of the following: the input circuit of the power battery, the power distribution circuit of the high-voltage power distribution unit, or any one of the at least one set of high-voltage components. The insulation detection circuit obtains the first insulation detection value of the object to be tested within a preset detection period; Based on the first insulation detection value and the preset fault threshold, the insulation detection result is determined, and the insulation detection result is used to indicate whether the object to be tested has an insulation abnormality.

[0007] Optionally, the object to be detected is the input circuit of the power battery, and the target contactor is all input contactors; controlling the target contactor to be in the target state includes: Control all input contactors to be in the off state; The step of determining the insulation detection result based on the first insulation detection value and the preset fault threshold includes: If the first insulation detection value is greater than or equal to the preset fault threshold, the insulation detection result is determined to be that the input circuit insulation of the power battery is normal. If the first insulation detection value is less than the preset fault threshold, the insulation detection result is determined to be an insulation abnormality in the input circuit of the power battery.

[0008] Optionally, the object to be tested is the power distribution circuit of the high-voltage power distribution unit, or the at least one set of high-voltage components; the method further includes: If the insulation test result indicates that the object under test has an insulation abnormality, control the target contactor to switch to the second state; The insulation detection circuit obtains the second insulation detection value of the object to be tested within a preset detection period; Based on the second insulation detection value, the insulation anomaly location of the object to be tested is determined, thus obtaining the insulation anomaly location of the object to be tested.

[0009] Optionally, the object to be tested is the power distribution circuit of a high-voltage power distribution unit, and the target contactors are: all input contactors and all output contactors. The first state is: all input contactors are in a closed state, and all output contactors are in an open state. If the insulation test result indicates that the object to be tested has an insulation abnormality, controlling the target contactors to switch to the second state includes: If the insulation test result indicates that the insulation of the power distribution circuit of the high-voltage power distribution unit is abnormal, control each of the input contactors to switch to the open state, while the states of the other contactors remain unchanged; The step of locating the insulation anomaly of the object under test based on the second insulation detection value to obtain the location of the insulation anomaly includes: When any input contactor is in the open state, if the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the power distribution circuit where any input contactor in the high-voltage power distribution unit is located. When all input contactors are in the open state, if the second insulation detection value is less than the preset fault threshold, the insulation abnormality location is determined to be all power distribution circuits of the high-voltage power distribution unit.

[0010] Optionally, the first type of system includes at least one, and each first type of system includes: a first group of output contactors and a first group of high-voltage components, the first group of high-voltage components including: a first high-voltage component with positive and negative contactors for the components and a second high-voltage component without positive and negative contactors for the components, the object to be tested is at least one first group of high-voltage components, the target contactor is: all input contactors and all contactors of at least one first type of system, the first state is: the target contactor is in a closed state, and if the insulation detection result indicates that the object to be tested has an insulation abnormality, controlling the target contactor to switch to a second state includes: If the insulation test result indicates an insulation abnormality in at least one high-voltage component of the first group, for each first type of system, control all contactors in the other first type of systems to be in the open state, and control the positive and negative contactors of the components in each first type of system to be in the open state, while the states of the other contactors remain unchanged. The step of locating the insulation anomaly of the object under test based on the second insulation detection value to obtain the location of the insulation anomaly includes: If the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the first high-voltage component of each first type of system; Otherwise, continue to keep the first output contactor in the first group of output contactors of each first type of system in the open state; If the new second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the wiring harness between the first group of high-voltage components and the first output contactor. If the new second insulation detection value is less than the preset fault threshold, the location of the insulation abnormality is determined to be the wiring harness between the first group of high-voltage components and the second output contactor in the first group of output contactors, or the second high-voltage component.

[0011] Optionally, the second type of system includes at least one, each second type of system including: a second group of output contactors and a third high-voltage component, the object to be tested is at least one third high-voltage component, the target contactor is: all input contactors and all contactors of at least one second type of system, the first state is: the target contactor is in a closed state, and if the insulation detection result indicates that the object to be tested has an insulation abnormality, controlling the target contactor to switch to the second state includes: If the insulation test result indicates an insulation abnormality in at least one third high-voltage component, for each second-class system, control all contactors in the other second-class systems to be in the open state, and control the third output contactor, the fourth output contactor, the positive contactor and / or the negative contactor in the positive and negative contactors of the second group of output contactors in each second-class system to be in the open state. The step of locating the insulation anomaly of the object under test based on the second insulation detection value to obtain the location of the insulation anomaly includes: If the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the third high-voltage component of each second type of system, and the location of the contactor in the disconnected state in each second type of system in the wiring harness between the third high-voltage component of each second type of system and the second set of output contactors.

[0012] Optionally, the third type of system includes at least one, and each third type of system includes: a third group of output contactors and a second group of high-voltage components, the second group of high-voltage components including: multiple fourth high-voltage components without contactors for positive and negative poles, the object to be tested is at least one of the second group of high-voltage components, the target contactor is: all output contactors and all contactors of at least one third type of system, the first state is: the target contactor is in a closed state, and if the insulation detection result indicates that the object to be tested has an insulation abnormality, controlling the target contactor to switch to the second state includes: If the insulation test result indicates an insulation abnormality of at least one second group of high-voltage components, for each third type of system, control all contactors in the other third type of systems to be in the open state, and control the fifth output contactor in the third group of output contactors in each third type of system to be in the open state and the sixth output contactor to be in the closed state. The step of locating the insulation anomaly of the object under test based on the second insulation detection value to obtain the location of the insulation anomaly includes: If the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the plurality of fourth high-voltage components, or the wiring harness between the plurality of fourth high-voltage components and the fifth output contactor; If the second insulation detection value is less than the preset fault threshold, the insulation abnormality location is determined to be one of the plurality of fourth high-voltage components, or the wiring harness between the plurality of fourth high-voltage components and the sixth output contactor.

[0013] Optionally, the method further includes: If an insulation abnormality alarm is received during operation, the contactor that was most recently closed will be switched to the open state according to the closing sequence of each contactor. If the third insulation detection value after the most recently closed contactor is switched to the open state is less than the preset fault threshold, the component contactor of the high-voltage component of the target type and the output contactor connected to the high-voltage component of the target type are switched to the open state. If the fourth insulation detection value after the contactor of the high-voltage component of the target type and the output contactor connected to the high-voltage component of the target type are switched to the open state is less than the preset fault threshold, the vehicle is controlled to stop and the high voltage is reduced.

[0014] Secondly, embodiments of this application also provide a vehicle high-voltage system, the vehicle high-voltage system comprising: a power battery, a high-voltage power distribution unit, and at least one set of high-voltage components; the high-voltage power distribution unit comprising: an insulation detection circuit, two input contactors, and at least one set of output contactors, the two ends of the power battery being respectively connected to the insulation detection circuit and the two input contactors, the two input contactors being respectively connected to two output contactors in each set of output contactors via positive and negative wiring harnesses, each set of output contactors being connected to a set of high-voltage components to form a system, and a vehicle controller being respectively connected to the insulation detection circuit, the two input contactors, and the at least one set of output contactors, the vehicle controller being used to execute the insulation failure fault detection method as described in any of the first aspects above.

[0015] Optionally, the system includes: a first type of system, a second type of system, and a third type of system, wherein a first high-voltage component with positive and negative contactors for the components and a second high-voltage component without positive and negative contactors for the components, together with a set of output contactors, constitute a first type of system; The third high-voltage component and a set of output contactors form a second type of system; A third type of system is formed by multiple fourth high-voltage components without positive and negative contactors and a set of output contactors.

[0016] The beneficial effects of this application are: The insulation failure fault detection method and vehicle high-voltage system provided in this application enable the vehicle controller to perform insulation anomaly detection on the input circuit of the power battery, the power distribution circuit of the high-voltage distribution unit, and each group of high-voltage components. This allows for automated and precise location of insulation failure faults, improving the efficiency of fault diagnosis. If an insulation failure fault occurs during vehicle operation, it can detect insulation failure faults in high-voltage components unrelated to vehicle operation. If the insulation failure fault is determined to be in a high-voltage component unrelated to vehicle operation, it can be controlled to stop working without stopping the vehicle and de-energizing it, thus not affecting vehicle operation. If the insulation failure fault is determined not to be in a high-voltage component unrelated to vehicle operation, the vehicle can be stopped and de-energized, greatly reducing the probability of stopping. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is an architectural diagram of a vehicle high-voltage system provided in an embodiment of this application; Figure 2 A flowchart illustrating the insulation failure detection method provided in this application embodiment. Figure 1 ; Figure 3 Flowchart of the insulation failure detection method provided in the embodiments of this application Figure 2 ; Figure 4 A flowchart illustrating the insulation failure detection process for a high-voltage power distribution unit provided in this application embodiment; Figure 5 A flowchart illustrating the insulation failure detection process of a first type of system provided in this application embodiment; Figure 6 This is a flowchart illustrating the insulation failure detection process of a second type of system provided in an embodiment of this application. Figure 7 A flowchart illustrating the insulation failure detection process of a third type of system provided in this application embodiment; Figure 8 Flowchart of the insulation failure detection method provided in the embodiments of this application Figure 3 . Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this application, but not all embodiments.

[0020] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0021] Furthermore, the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Additionally, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0022] It should be noted that, where there is no conflict, the features in the embodiments of this application can be combined with each other.

[0023] To better understand the insulation failure fault detection method of this scheme, the specific implementation of the vehicle high-voltage system applied in this application will be explained first.

[0024] Figure 1 The architecture diagram of the vehicle high-voltage system provided in the embodiments of this application is as follows: Figure 1 As shown, the vehicle high-voltage system includes: a power battery 10, a high-voltage power distribution unit 20, and at least one set of high-voltage components 30; the high-voltage power distribution unit 20 includes: an insulation detection circuit 21, two input contactors, and at least one set of output contactors. The two ends of the power battery 10 are respectively connected to the insulation detection circuit 21 and the two input contactors. The two input contactors are respectively connected to the two output contactors in each set of output contactors through the positive terminal harness HV+ and the negative terminal harness HV-. Each set of output contactors is connected to a set of high-voltage components to form a system.

[0025] The vehicle controller is connected to the insulation detection circuit 21, two input contactors and at least one set of output contactors to execute the insulation failure fault detection method provided in this application.

[0026] In this embodiment, as Figure 1 As shown, the power battery 10, high-voltage power distribution unit 20, and at least one set of high-voltage components 30 are used as the objects to be tested. A detection circuit is formed between the insulation detection circuit 21 and the vehicle body (or ground). By applying a small current in the detection circuit, the insulation detection circuit 21 calculates the insulation detection value by measuring the voltage drop. The insulation detection value is the insulation resistance value. If there is a leakage path to ground in the detection circuit, the insulation resistance value will be very small; if there is no leakage path to ground in the detection circuit, the insulation resistance value will be very large. The vehicle controller determines whether the object under test has an insulation failure fault by judging whether the insulation detection value detected by the insulation detection circuit 21 is less than a preset fault threshold.

[0027] Among them, the high-voltage components included in the high-voltage system of the whole vehicle are classified, and the high-voltage components are combined with each group of output contactors based on their type and quantity to form a system.

[0028] For each system, the vehicle controller can individually detect the high-voltage components it contains, thereby accurately locating high-voltage components with insulation failure faults. If the high-voltage component with insulation failure faults is a high-voltage component unrelated to the operation of the new energy vehicle, it can be controlled to stop working without stopping the vehicle and de-energizing it, thus not affecting the vehicle's operation. Controlling the vehicle to stop and de-energize it is only necessary when the high-voltage component with insulation failure faults is a high-voltage component related to the operation of the new energy vehicle, greatly reducing the probability of stopping.

[0029] In some embodiments, such as Figure 1 As shown, the system includes: a first type of system A, a second type of system B, and a third type of system C. A first type of system A consists of a first high-voltage component with positive and negative contactors and a second high-voltage component without positive and negative contactors, along with a set of output contactors; a third high-voltage component and a set of output contactors constitute a second type of system B; and multiple fourth high-voltage components without positive and negative contactors and a set of output contactors constitute a third type of system C.

[0030] In this embodiment, multiple high-voltage components are classified. The types of high-voltage components can be classified as follows: driving type, safety type, performance type, and comfort type. For example, driving type high-voltage components can be drive motors, safety type high-voltage components can be brake motors, performance type high-voltage components can be battery thermal management systems, and comfort type high-voltage components can be positive temperature coefficient (PTC) thermistors for heating.

[0031] The system provided in this application is divided into three categories. For safety-type high-voltage components and performance-type high-voltage components, the first category system A is preferred. Specifically, according to whether the high-voltage component has a positive and negative contactor, safety-type high-voltage components with and without positive and negative contactors are combined in pairs and connected to a set of output contactors to form a first category system A. After the pairwise combination, if there are still remaining safety-type high-voltage components, each remaining safety-type high-voltage component can also be connected to a set of output contactors to form a second category system B.

[0032] The combination of performance-type high-voltage components and safety-type high-voltage components to form the first type of system A is the same, and will not be repeated here. After the two are combined, if the remaining performance-type high-voltage components have positive and negative contactors, each of them can be connected to a set of output contactors to form a second type of system B. If the remaining performance-type high-voltage components do not have positive and negative contactors, they can be connected together to a set of output contactors to form a third type of system C.

[0033] For high-voltage components in the vehicle category, a second-type system B is adopted, in which each high-voltage component of a performance category is connected to a set of output contactors to form a second-type system B.

[0034] For comfort-type high-voltage components, a third system C is preferred, which involves connecting multiple comfort-type high-voltage components to a set of output contactors to form a third system C. The number of comfort-type high-voltage components forming the third system can be a preset number. If the number of comfort-type high-voltage components is large, multiple third systems C can be formed. In some embodiments, if a comfort-type high-voltage component has positive and negative contactors, it can also be combined with a comfort-type high-voltage component without positive and negative contactors through a set of output contactors to form a first system A.

[0035] Based on the above-mentioned vehicle high-voltage system, the specific implementation of the insulation failure fault detection method provided in this application will be described below with reference to specific embodiments.

[0036] Figure 2 Flowchart of the insulation failure detection method provided in the embodiments of this application Figure 1 ,like Figure 2 As shown, the method may include: S101. Based on the object to be tested in the vehicle's high-voltage system, control the target contactor to be in the first state; wherein, the object to be tested is any one of the following: the input circuit of the power battery, the power distribution circuit of the high-voltage power distribution unit, or at least one set of high-voltage components.

[0037] In this embodiment, the solution can perform insulation failure detection on the input circuit of the power battery, the power distribution circuit of the high-voltage power distribution unit, and at least one set of high-voltage components. For non-vehicle-related high-voltage components in the at least one set of high-voltage components, insulation failure detection can be performed during driving or after parking. For the input circuit of the power battery, the power distribution circuit of the high-voltage power distribution unit, and the vehicle-related high-voltage components, insulation failure detection needs to be performed after parking.

[0038] For different objects to be detected, the corresponding target contactors are different, and the first state of the target contactors is also different. The state of the contactor is either closed or open. The first state can be that all target contactors are closed, all target contactors are open, or some target contactors are closed and others are open.

[0039] If the object to be tested is the input circuit of a power battery, the target contactors are all the input contactors, i.e., as shown below. Figure 1 As shown in KT01 and KT02, the first state is when all input contactors are in the open state.

[0040] If the object to be tested is the power distribution circuit of a high-voltage power distribution unit, the target contactors are all input contactors and all output contactors, i.e. Figure 1 The input contactors KT01 and KT02, and the output contactors KT11 and KT21, KT12 and KT22, KT13 and KT23, KT14 and KT24, KT15 and KT25, KT16 and KT26 shown are in the first state where all input contactors are closed and all output contactors are open.

[0041] If the objects to be tested are all high-voltage components, and the target contactors are all input contactors and all output contactors, the first state is that all input contactors and all output contactors are in the closed state.

[0042] If the unit to be tested is any group of high-voltage components, and the target contactors are all the input contactors and the output contactors of any group of high-voltage components, the first state is that all the input contactors are closed, the output contactors connected to any group of high-voltage components are closed, and the output contactors connected to other high-voltage components are open.

[0043] S102. Obtain the first insulation detection value of the object to be tested detected by the insulation detection circuit within a preset detection period.

[0044] In this embodiment, after the target contactor is in the first state, the object to be tested forms a detection loop between the insulation detection circuit and the vehicle body (or ground). By applying a small current in the detection loop, the insulation detection circuit calculates the first insulation detection value by measuring the voltage drop within a preset detection period, and the vehicle controller obtains the first insulation detection value detected by the insulation detection circuit.

[0045] S103. Determine the insulation test result based on the first insulation test value and the preset fault threshold. The insulation test result is used to indicate whether there is an insulation abnormality in the object to be tested.

[0046] In this embodiment, if the first insulation detection value is greater than or equal to the preset fault threshold, it is determined that there is no leakage path to ground in the detection circuit between the object to be tested and the vehicle body (or ground), that is, the insulation of the object to be tested is normal. If the first insulation detection value is less than the preset fault threshold, it is determined that there is a leakage path to ground in the detection circuit between the object to be tested and the vehicle body (or ground), that is, the insulation of the object to be tested is abnormal.

[0047] The insulation failure detection method provided in the above embodiments allows the vehicle controller to perform insulation anomaly detection on the input circuit of the power battery, the power distribution circuit of the high-voltage distribution unit, and each group of high-voltage components. This enables automated and precise location of insulation failure faults, improving the efficiency of troubleshooting. If an insulation failure occurs during driving, insulation failure detection can be performed on high-voltage components unrelated to vehicle operation. If the insulation failure is determined to be on a high-voltage component unrelated to vehicle operation, it can be controlled to stop working without stopping the vehicle and de-energizing it, thus not affecting vehicle operation. If the insulation failure is determined not to be on a high-voltage component unrelated to vehicle operation, the vehicle can be stopped and de-energized, greatly reducing the probability of stopping.

[0048] In one possible implementation, the object to be detected is the input circuit of the power battery, and the target contactors are all input contactors. The process of controlling the target contactors to be in the target state in S101 can include: Keep all input contactors in the off state.

[0049] The process of determining the insulation test result based on the first insulation test value and the preset fault threshold in S103 above may include: If the first insulation detection value is greater than or equal to the preset fault threshold, the insulation detection result is determined to be that the power battery's input circuit insulation is normal; if the first insulation detection value is less than the preset fault threshold, the insulation detection result is determined to be that the power battery's input circuit insulation is abnormal.

[0050] In this embodiment, as Figure 1 As shown, all input contactors, namely KT01 and KT02, are used to connect or disconnect the power battery from the high-voltage bus of the high-voltage distribution unit. When KT01 and KT02 are in the off state, the connection between the power battery and the high-voltage bus of the high-voltage distribution unit is completely disconnected. A detection circuit is formed between the input circuit of the power battery, the insulation detection circuit, and the vehicle body (or ground). The insulation detection circuit injects a small current into the input circuit of the power battery and detects the voltage drop in the detection circuit based on the small current. The first insulation detection value to ground is calculated based on the voltage drop.

[0051] The vehicle controller compares the first insulation detection value with the preset fault threshold. If the first insulation detection value is greater than or equal to the preset fault threshold, it determines that there is no leakage path to ground in the input circuit of the power battery, that is, the insulation of the input circuit of the power battery is normal. If the first insulation detection value is less than the preset fault threshold, it determines that there is a leakage path to ground in the input circuit of the power battery, that is, the insulation of the input circuit of the power battery is abnormal.

[0052] Among them, the insulation abnormality of the power battery input circuit may be due to internal insulation failure of the power battery, abnormality of the high-voltage wiring harness of the power battery input circuit, or poor insulation of the high-voltage components on the input circuit, which requires further investigation.

[0053] In some embodiments, if the first insulation detection value is greater than or equal to a preset fault threshold, the vehicle controller returns a True indication message to the user to indicate that the input circuit insulation of the power battery is normal; if the first insulation detection value is less than the preset fault threshold, the vehicle controller returns a False indication message to the user to indicate that the input circuit insulation of the power battery is abnormal.

[0054] In another possible implementation, the object to be detected is the power distribution circuit of the high-voltage power distribution unit, the target contactors are all the input contactors and all the output contactors, and the first state is that all the input contactors are in the closed state and all the output contactors are in the open state.

[0055] In this embodiment, as Figure 1 As shown, all output contactors, namely KT11 and KT21, KT12 and KT22, KT13 and KT23, KT14 and KT24, KT15 and KT25, KT16 and KT26, are used to connect or disconnect the high-voltage busbars and high-voltage components of the high-voltage power distribution unit. When control KT01 and KT02 are in the closed state and KT11 and KT21, KT12 and KT22, KT13 and KT23, KT14 and KT24, KT15 and KT25, KT16 and KT26 are in the open state, the connection between the power battery and multiple high-voltage busbars of the high-voltage power distribution unit is made conductive, and the connection between multiple high-voltage busbars and high-voltage components of the high-voltage power distribution unit is disconnected. In this way, it can be ensured that when performing insulation failure fault detection on the power distribution circuit of the high-voltage power distribution unit, it will not be affected by any abnormalities that may exist in the high-voltage components.

[0056] The power distribution circuit of the high-voltage power distribution unit is formed between multiple high-voltage busbars, the insulation detection circuit, and the vehicle body (or ground). The insulation detection circuit injects a weak current into the power distribution circuit of the high-voltage power distribution unit and detects the voltage drop in the detection circuit based on the weak current. The first insulation detection value to ground is calculated based on the voltage drop.

[0057] The vehicle controller determines the magnitude of the first insulation detection value and the preset fault threshold. If the first insulation detection value is greater than or equal to the preset fault threshold, it determines that there is no leakage path to ground in the power distribution circuit of the high-voltage power distribution unit, that is, the insulation of the power distribution circuit of the high-voltage power distribution unit is normal. If the first insulation detection value is less than the preset fault threshold, it determines that there is a leakage path to ground in the power distribution circuit of the high-voltage power distribution unit, that is, the insulation of the power distribution circuit of the high-voltage power distribution unit is abnormal.

[0058] Among them, insulation abnormalities in the power distribution circuit of the high-voltage power distribution unit may be due to abnormalities in the wiring harnesses of any one or more high-voltage busbars, requiring further investigation.

[0059] In some embodiments, if the first insulation detection value is greater than or equal to a preset fault threshold, the vehicle controller returns a True indication message to the user to indicate that the insulation of the power distribution circuit of the high-voltage power distribution unit is normal; if the first insulation detection value is less than the preset fault threshold, the vehicle controller returns a False indication message to the user to indicate that the insulation of the power distribution circuit of the high-voltage power distribution unit is abnormal.

[0060] In another possible implementation, the objects to be detected are all high-voltage components, the target contactors are all input contactors and all output contactors, and the first state is that all input contactors and all output contactors are in the closed state.

[0061] In this embodiment, as Figure 1 As shown, when controls KT01 and KT02 are in the closed state, and KT11 and KT21, KT12 and KT22, KT13 and KT23, KT14 and KT24, KT15 and KT25, KT16 and KT26 are also in the closed state, the connection between the power battery and multiple high-voltage busbars of the high-voltage power distribution unit is completed, and the connection between multiple high-voltage busbars of the high-voltage power distribution unit and multiple sets of high-voltage components is completed.

[0062] A detection loop is formed between all high-voltage components, the insulation detection circuit, and the vehicle body (or ground). The insulation detection circuit injects a small current into the detection loop and detects the voltage drop across the detection loop based on this small current. The first insulation detection value to ground is calculated based on the voltage drop.

[0063] The vehicle controller determines the magnitude of the first insulation detection value and the preset fault threshold. If the first insulation detection value is greater than or equal to the preset fault threshold, it determines that there is no leakage path to ground in all high-voltage components, that is, the insulation of the high-voltage components is normal. If the first insulation detection value is less than the preset fault threshold, it determines that there is a leakage path to ground in at least one high-voltage component, that is, the insulation of the high-voltage component is abnormal.

[0064] Among them, the insulation abnormality of high-voltage components can be the insulation abnormality of any high-voltage component. If the insulation of the distribution circuit of the high-voltage power distribution unit has not been ruled out beforehand, the insulation abnormality of the high-voltage component includes the abnormality of the component itself, or the abnormality of the wiring harness connected to the component. If the insulation of the distribution circuit of the high-voltage power distribution unit has been determined to be normal beforehand, the insulation abnormality of the high-voltage component only includes the abnormality of the component itself.

[0065] In some embodiments, if the first insulation detection value is greater than or equal to a preset fault threshold, the vehicle controller returns a True indication message to the user to indicate that the insulation of all high-voltage components is normal; if the first insulation detection value is less than the preset fault threshold, the vehicle controller returns a False indication message to the user to indicate that the insulation of at least one high-voltage component is abnormal.

[0066] In another possible implementation, the unit to be detected is any group of high-voltage components, the target contactors are all the input contactors and the output contactors of any group of high-voltage components, the first state is that all the input contactors are closed, the output contactors connected to any group of high-voltage components are closed, and the output contactors connected to other high-voltage components are open.

[0067] In this embodiment, after confirming that the insulation of the power distribution circuit of the high-voltage power distribution unit is normal, the insulation failure faults of each group of high-voltage components can be investigated separately.

[0068] Specifically, the output contactor connected to each group of high-voltage components is kept in a closed state, while the output contactors connected to other groups of high-voltage components remain in an open state. At this time, only one group of high-voltage components forms a detection loop with the insulation detection circuit and the vehicle body (or ground). The vehicle controller judges the magnitude of the first insulation detection value and the preset fault threshold. If the first insulation detection value is greater than or equal to the preset fault threshold, it is determined that there is no leakage path to ground in that group of high-voltage components, that is, the insulation of that group of high-voltage components is normal. If the first insulation detection value is less than the preset fault threshold, it is determined that there is a leakage path to ground in that group of high-voltage components, that is, the insulation of that group of high-voltage components is abnormal.

[0069] In some embodiments, if the first insulation detection value is greater than or equal to a preset fault threshold, the vehicle controller returns a True indication message to the user to indicate that the insulation of the group of high-voltage components is normal; if the first insulation detection value is less than the preset fault threshold, the vehicle controller returns a False indication message to the user to indicate that the insulation of the group of high-voltage components is abnormal.

[0070] It should be noted that if insulation failure fault detection is performed on the input circuit of the power battery, the power distribution circuit of the high-voltage power distribution unit, and at least one set of high-voltage components, the object identifier of the object to be tested should also be carried when returning the True or False indication information to indicate whether the object to be tested has normal insulation or abnormal insulation.

[0071] Furthermore, the object to be tested is the power distribution circuit of a high-voltage power distribution unit, or at least one set of high-voltage components. Figure 3 Flowchart of the insulation failure detection method provided in the embodiments of this application Figure 2 ,like Figure 3 As shown, the method may further include: S104. If the insulation test result indicates that the object under test has an insulation abnormality, control the target contactor to switch to the second state.

[0072] In this embodiment, as described above, when the distribution circuit of the high-voltage distribution unit is determined based on the first insulation detection value, or when at least one set of high-voltage components has an insulation abnormality, further judgment is required to locate the insulation abnormality.

[0073] Specifically, the target contactor is controlled to switch from the first state to the second state, which specifically involves controlling the portion of the target contactor that is in the closed state to switch to the open state.

[0074] In some embodiments, if the object to be detected is the power distribution circuit of the high-voltage power distribution unit, then the two input contactors KT01 and KT02 are controlled to switch from the closed state to the open state respectively.

[0075] In other embodiments, if the object to be tested is all high-voltage components or any group of high-voltage components, then some of the output contactors in all output contactors are controlled to switch from the closed state to the open state.

[0076] S105. Obtain the second insulation detection value of the object to be tested detected by the insulation detection circuit within a preset detection period.

[0077] In this embodiment, the insulation detection circuit detects the second insulation detection value in the same way as the first insulation detection value in S102 described above, and will not be repeated here.

[0078] S106. Based on the second insulation test value, locate the insulation abnormality of the object to be tested to obtain the location of the insulation abnormality of the object to be tested.

[0079] In this embodiment, after the part of the control target contactor that was in the closed state is switched to the open state, if the second insulation detection value is greater than or equal to the preset fault threshold, it means that the insulation failure fault that occurred before has been eliminated because the circuit where the part of the contactor is located is disconnected. This also means that the insulation failure fault that occurred before was caused by the circuit where the part of the contactor is located. Therefore, the insulation abnormality location is the circuit where the part of the contactor that has been switched to the open state is located.

[0080] If the second insulation detection value is less than the preset fault threshold, it means that the insulation failure that occurred previously was not eliminated by the disconnection of the circuit where some contactors are located. This means that the insulation failure that occurred previously was either caused by the circuit where the remaining contactors are still in the closed state, or it was caused by the circuit where some contactors switched to the open state and the circuit where the remaining contactors are still in the closed state. Therefore, the insulation abnormality location is: the circuit where the remaining contactors are still in the closed state, or the circuit where all contactors in the closed state in the first state are located.

[0081] The insulation failure detection method provided in the above embodiments, after controlling the target contactor to be in the first state and determining whether there is an insulation abnormality in the object to be tested, further locates the specific location of the abnormality in the object to be tested by controlling the target contactor to be in the second state, thereby improving the accuracy of abnormality location.

[0082] In one possible implementation, the object to be tested is the power distribution circuit of a high-voltage power distribution unit, and the target contactors are: all input contactors and all output contactors. The first state is: all input contactors are in the closed state and all output contactors are in the open state. If the insulation test result indicates that the object to be tested has an insulation abnormality, the process of controlling the target contactors to switch to the second state in S104 above may include: If the insulation test result indicates that the insulation of the power distribution circuit of the high-voltage power distribution unit is abnormal, control each of the input contactors to switch to the open state, while the states of the other contactors remain unchanged.

[0083] The process of S106 above, which locates the insulation anomaly of the object to be tested based on the second insulation test value, and obtains the location of the insulation anomaly of the object to be tested, may include: When any input contactor is in the open state, if the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the power distribution circuit where any input contactor in the high-voltage power distribution unit is located; when all input contactors are in the open state, if the second insulation detection value is less than the preset fault threshold, the insulation abnormality location is determined to be all power distribution circuits of the high-voltage power distribution unit.

[0084] In this embodiment, as Figure 1 As shown, when the control input contactors KT01 and KT02 are in the closed state, and the output contactors KT11 and KT21, KT12 and KT22, KT13 and KT23, KT14 and KT24, KT15 and KT25, KT16 and KT26 are in the open state, if the first insulation detection value is less than the preset abnormal threshold, it is determined that there may be a ground leakage path between the positive and / or negative circuits of the high-voltage power distribution unit, and further location of the insulation abnormality is required.

[0085] Specifically, the system controls one of the two input contactors to switch to the open state, opening the first distribution circuit of the high-voltage power distribution unit. An insulation detection circuit then performs insulation testing on the second distribution circuit, determining a second insulation detection value. If the second insulation detection value is greater than or equal to a preset fault threshold, the insulation abnormality is eliminated, meaning the previous insulation abnormality occurred in the first distribution circuit where the input contactor was switched to the open state. If the second insulation detection value is less than the preset fault threshold, the insulation abnormality persists. Then, one of the two input contactors is switched back to the closed state, and the other is switched to the open state, opening the second distribution circuit of the high-voltage power distribution unit. The insulation detection circuit then performs insulation testing on the first distribution circuit, determining a second insulation detection value. If the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality is eliminated, meaning the previous insulation abnormality occurred in the second distribution circuit where the input contactor was switched to the open state. If the second insulation detection value is less than the preset fault threshold, the insulation abnormality persists, indicating that both distribution circuits have insulation abnormalities, meaning the insulation abnormalities occur in both distribution circuits of the high-voltage power distribution unit.

[0086] Example, Figure 4 This is a flowchart illustrating the insulation failure detection process for a high-voltage power distribution unit provided in an embodiment of this application. Figure 4 As shown, the process may include: S201, control input contactors KT01 and KT02 are in the closed state, and output contactors KT11 and KT21, KT12 and KT22, KT13 and KT23, KT14 and KT24, KT15 and KT25, KT16 and KT26 are in the open state.

[0087] S202. Determine whether the insulation failure fault result is True or False. True indicates that the insulation is normal, and False indicates that the insulation is abnormal. If it returns True, it is determined that the insulation of the power distribution circuit of the high-voltage power distribution unit is normal. If it returns False, then jump to S203.

[0088] S203, control input contactor KT01 is switched to the open state.

[0089] S204. Determine whether the insulation failure fault result is True or False. If it returns True, then it is determined that the positive circuit insulation of the high-voltage power distribution unit is abnormal. If it returns False, then jump to S205.

[0090] S205, control input contactor KT01 is switched to the closed state, and KT02 is switched to the open state.

[0091] S206. Determine whether the insulation failure fault result is True or False. If it returns True, it is determined that the insulation of the negative circuit of the high-voltage power distribution unit is abnormal. If it returns False, it is determined that both the positive and negative circuits of the high-voltage power distribution unit have insulation abnormalities.

[0092] It should be noted that the flowchart above is merely an exemplary execution sequence, and the determination of the insulation abnormality location of the power distribution circuit in the high-voltage power distribution unit is not limited to... Figure 4 The execution order shown is one possible sequence; other execution orders are also within the scope of protection of this solution, and will not be elaborated upon in this embodiment.

[0093] The insulation failure fault detection method provided in the above embodiments controls each input contactor to switch to the open state, and determines the location of insulation abnormality in the power distribution circuit of the high-voltage power distribution unit based on the second insulation detection value and the preset fault threshold when each input contactor is open, thereby achieving accurate location of insulation failure fault.

[0094] In one possible implementation, the first type of system includes at least one, each first type of system including: a first group of output contactors and a first group of high-voltage components, the first group of high-voltage components including: a first high-voltage component with positive and negative contactors and a second high-voltage component without positive and negative contactors, the object to be detected is at least one first group of high-voltage components, the target contactor is: all input contactors and all contactors of at least one first type of system, and the first state is: the target contactor is in the closed state.

[0095] In this embodiment, as Figure 1 As shown, the first type of system A may include one or more, Figure 1Two systems are shown. System A1 consists of output contactors KT11 and KT21, a first high-voltage component A1-1, and a second high-voltage component A1-2. System A2 consists of output contactors KT12 and KT22, a first high-voltage component A2-1, and a second high-voltage component A2-2. The first high-voltage component A1-1 has a positive contactor KT31 and a negative contactor KT41. The first high-voltage component A2-1 has a positive contactor KT32 and a negative contactor KT42. The second high-voltage components A1-2 and A2-2 do not have positive and negative contactors.

[0096] In S101, the object to be tested can be the first group of high-voltage components of all first-class systems. The first state is that the input contactors KT01 and KT02 are in the closed state, the output contactors KT11 and KT21, KT12 and KT22 of all first-class systems, and the positive and negative contactors KT31 and KT41, KT32 and KT42 of the components are in the closed state. If the first insulation detection value detected by the insulation detection circuit is less than the preset insulation threshold, it is determined that there is an insulation abnormality in the high-voltage components of all first-class systems. The insulation abnormality may be an insulation abnormality of the component itself, or it may be an insulation abnormality of the wiring harness between the component and the output contactor (provided that the high-voltage distribution unit has been excluded from having an insulation abnormality).

[0097] In this situation, it is necessary to further pinpoint which group of high-voltage components in the first type of system has an insulation anomaly, and which component within that group of high-voltage components has the anomaly. The method for locating the insulation anomaly is the same for each type of system; this solution uses... Figure 1 The following explanation uses system A1 as an example.

[0098] If the insulation test result indicates that the object under test has an insulation abnormality, the process of controlling the target contactor to switch to the second state in the above S104 may include: If the insulation test results indicate that at least one high-voltage component in the first group has an insulation abnormality, for each first-class system, all contactors in the other first-class systems are controlled to be in the open state, and the positive and negative contactors of the components in each first-class system are controlled to be in the open state, while the states of the other contactors remain unchanged.

[0099] In this embodiment, if it is determined that there is an insulation abnormality in the first group of high-voltage components of all first-class systems, all other first-class systems except system A1 can be controlled first, for example... Figure 1In system A2, all output contactors KT12 and KT22 and all component positive and negative contactors KT32 and KT42 are in the open state. In system A1, all output contactors KT11 and KT21 and all component positive and negative contactors KT31 and KT41 are in the closed state. It is determined whether the second insulation detection value is greater than or equal to the preset fault threshold. If the second insulation detection value is greater than or equal to the preset fault threshold, it is determined that the insulation failure faults of all previous first-type systems are not in system A1, and other first-type systems such as system A2 are investigated. If the second insulation detection value is less than the preset fault threshold, it is determined that the previous insulation failure faults are in system A1, and the insulation abnormality location can be further located in system A1.

[0100] It should be noted that stating that the previous insulation failure occurred in system A1 does not mean that the insulation failure did not occur in other Class I systems, because the insulation failure may occur in multiple Class I systems, and troubleshooting is still required for other Class I systems as well.

[0101] Furthermore, if an insulation failure is found in system A1, the first high-voltage component in system A1 with the positive and negative contactors of the component is further tested for an insulation failure.

[0102] Specifically, taking system A1 as an example, in controlling all other Class I systems besides system A1, for example... Figure 1 When all output contactors KT12 and KT22 and all component positive and negative contactors KT32 and KT42 of system A2 are in the open state, the component positive and negative contactors KT31 and KT41 of system A1 are also in the open state. Determine whether the insulation failure fault has been eliminated under this condition.

[0103] The process of S106 above, which locates the insulation anomaly of the object to be tested based on the second insulation test value, and obtains the location of the insulation anomaly of the object to be tested, may include: If the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the first high-voltage component of each first-class system; otherwise, the first output contactor in the first group of output contactors of each first-class system is kept in the open state.

[0104] In this embodiment, it is determined whether the second insulation detection value at this time is greater than or equal to the preset fault threshold. If the second insulation detection value at this time is greater than or equal to the preset fault threshold, the location of the insulation failure fault of all previous first-type systems is determined to be the first high-voltage component A1-1 of system A1 itself.

[0105] If the second insulation detection value is less than the preset fault threshold, then the insulation failure faults of all previous Class I systems may be in other locations of System A1 or in other Class I systems. It is necessary to first determine whether they are in other locations of System A1.

[0106] Specifically, other locations in system A1 can be the second high-voltage component A1-2, or the wiring harness HV+ of the positive circuit connected to the first high-voltage component A1-1 and the second high-voltage component A1-2, and the wiring harness HV- of the negative circuit.

[0107] Either of the output contactors KT11 and KT21 of system A1 is used as the first output contactor. The first output contactor is controlled to be in the open state, and it is determined whether the insulation failure fault is eliminated under this condition.

[0108] If the new second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the wiring harness between the first group of high-voltage components and the first output contactor.

[0109] If the new second insulation detection value is less than the preset fault threshold, the insulation abnormality location is determined to be the wiring harness between the first group of high-voltage components and the second output contactor in the first group of output contactors, or the second high-voltage component.

[0110] In this embodiment, it is determined whether the second insulation detection value is greater than or equal to a preset fault threshold. If the second insulation detection value is greater than or equal to the preset fault threshold, the location of the insulation failure fault of all previous first-type systems is determined to be the wiring harness between the first high-voltage component A1-1, the second high-voltage component A1-2, and the first output contactor. If the second insulation detection value is less than the preset fault threshold, since the second high-voltage component does not have a component positive and negative contactor, it is impossible to rule out whether the insulation failure fault is a component insulation failure fault or a wiring harness insulation failure fault. The location of the insulation abnormality is determined to be the wiring harness between the first high-voltage component A1-1, the second high-voltage component A1-2, and the second output contactor, or the second high-voltage component A1-2 itself.

[0111] It should be noted that, since it has not yet been determined whether the insulation failure faults of all the first-class systems exist in other first-class systems, if the fault still exists after performing the above steps to detect the fault in system A1, it can only be temporarily assumed that the wiring harness between the first high-voltage component A1-1, the second high-voltage component A1-2, and the second output contactor, or the second high-voltage component A1-2 itself, has an insulation failure fault. If, when performing fault detection on other first-class systems, it is clearly determined that the insulation failure fault exists in other first-class systems (i.e., by controlling the contactor of the corresponding first-class system to disconnect, so that the second insulation detection value is greater than or equal to the preset fault threshold, thereby eliminating the insulation failure fault), then it is determined that the wiring harness between the first high-voltage component A1-1, the second high-voltage component A1-2, and the second output contactor, or the second high-voltage component A1-2 itself, does not have an insulation failure fault.

[0112] The above embodiments only describe the location of insulation failure faults in one type of first system. The location of insulation failure faults in other types of first systems is similar and will not be repeated here. It should be noted that if the second insulation detection value is detected to be greater than or equal to the preset fault threshold at any step of the fault detection process, thus eliminating the insulation failure fault, it means that the insulation abnormality location has been accurately located, and it is no longer necessary to continue fault location for the remaining locations of the first type of system.

[0113] Example, Figure 5 The flowchart of the insulation failure detection process for the first type of system provided in the embodiments of this application is as follows: Figure 5 As shown, the process may include: S301, control input contactors KT01 and KT02 are in the closed state, and all output contactors KT11 and KT21, KT12 and KT22 of the first type system A and all component positive and negative contactors KT31 and KT41, KT32 and KT42 are in the closed state.

[0114] S302. Determine whether the insulation failure fault result is True or False. If it returns True, it is determined that the insulation of the first type of system A is normal. If it returns False, then jump to S303.

[0115] S303, the output contactors KT12 and KT22 of the control system A2 and the positive and negative contactors KT32 and KT42 of the components are in the open state.

[0116] S304. Determine whether the insulation failure fault result is True or False. If it returns True, jump to S305; if it returns False, jump to S306.

[0117] S305. After confirming that there is no insulation abnormality in system A1, further locate the insulation abnormality in system A2.

[0118] S306. It is determined that there is an insulation abnormality in system A1, and further insulation abnormality detection is performed on system A1.

[0119] S307, The positive and negative contactors KT31 and KT41 of the control system A1 are in the open state.

[0120] S308. Determine whether the insulation failure fault result is True or False. If it returns True, then the insulation of the first high-voltage component A1-1 is confirmed to be abnormal. If it returns False, then jump to S309.

[0121] S309, The output contactor KT11 of control system A1 is in the open state.

[0122] S310. Determine whether the insulation failure result is True or False. If it returns True, then determine that the positive wire harness HV+ insulation of the circuit containing the first high-voltage component A1-1 and the second high-voltage component A1-2 is abnormal. If it is determined that the negative wire harness HV- insulation of the circuit containing the first high-voltage component A1-1 and the second high-voltage component A1-2 is abnormal, or the insulation of the second high-voltage component A1-2 is abnormal.

[0123] The insulation failure fault detection method provided in the above embodiments controls the positive and negative contactors and output contactors of the components in each first type of system to be in an open state. Based on the second insulation detection value and the preset fault threshold when the positive and negative contactors and output contactors of the components are open, the insulation abnormality location of the high-voltage components in each first type of system is determined, thereby achieving accurate location of insulation failure faults.

[0124] In one possible implementation, the second type of system includes at least one, each second type of system including: a second set of output contactors and a third high-voltage component, the object to be tested is at least one third high-voltage component, the target contactor is: all input contactors and all contactors of at least one second type of system, and the first state is: the target contactor is in the closed state.

[0125] In this embodiment, as Figure 1 As shown, the second type of system B may include one or more, Figure 1 Two are shown. System B1 consists of output contactors KT13 and KT23 and a third high-voltage component B1-1. System B2 consists of output contactors KT14 and KT24 and a third high-voltage component B2-1. The third high-voltage component B1-1 has a positive contactor KT33 and a negative contactor KT43. The third high-voltage component B2-1 does not have positive and negative contactors.

[0126] In S101, the object to be tested can be the third high-voltage component of all second-class systems. The first state is that the input contactors KT01 and KT02 are in the closed state, the output contactors KT13 and KT23, KT14 and KT24 of all second-class systems, and the positive and negative contactors KT33 and KT43 of the component are in the closed state. At this time, if the first insulation detection value detected by the insulation detection circuit is less than the preset insulation threshold, it is determined that the third high-voltage component in all second-class systems may have an insulation abnormality. The insulation abnormality may be an insulation abnormality of the component itself, or it may be an insulation abnormality of the wiring harness between the component and the output contactor (provided that the high-voltage distribution unit has been ruled out as not having an insulation abnormality).

[0127] In this case, it is necessary to further locate which third high-voltage component in the second type of system has an insulation abnormality, and the location of the insulation abnormality in the third high-voltage component.

[0128] If the insulation test result indicates that the object under test has an insulation abnormality, the process of controlling the target contactor to switch to the second state in the above S104 may include: If the insulation test result indicates an insulation abnormality in at least one third high-voltage component, for each second-class system, control all contactors in the other second-class systems to be in the open state, and control the third output contactor, fourth output contactor, positive contactor and / or negative contactor in the positive and negative contactors of the second set of output contactors in each second-class system to be in the open state.

[0129] In this embodiment, if it is determined that there is an insulation abnormality in the third high-voltage component of all second-type systems, all contactors of one second-type system can be kept closed while all contactors of other second-type systems are in the open state.

[0130] like Figure 1 As shown, if all output contactors KT13 and KT23 of control system B1 and the positive and negative contactors KT33 and KT43 of the components remain closed, then all output contactors KT14 and KT24 of control system B2 are open. If all output contactors KT14 and KT24 of control system B2 remain closed, then all output contactors KT13 and KT23 of control system B1 and the positive and negative contactors KT33 and KT43 of the components are open.

[0131] Determine whether the second insulation detection value at this time is greater than or equal to the preset fault threshold. If the second insulation detection value at this time is greater than or equal to the preset fault threshold, it is determined that the insulation failure faults of all previous second-type systems are not in the second-type systems that maintain the closed state. If the second insulation detection value at this time is less than the preset fault threshold, it is determined that the insulation failure faults of all previous second-type systems are in the second-type systems that maintain the closed state.

[0132] Among them, such as Figure 1 As shown, the third high-voltage component is divided into the third high-voltage component B1-1 with component positive and negative contactors and the third high-voltage component B2-1 without component positive and negative contactors. If it is determined that the insulation failure of all previous second-type systems is in system B1 which is in the closed state, the output contactors KT13 and KT23 of system B1, the component positive and negative contactors KT33 and / or KT43 of the third high-voltage component B1-1 can be in the open state.

[0133] If it is determined that the insulation failure of all previous Type II systems occurred in system B2, which is in a closed state, then the output contactors KT13 and KT23 of system B2 can be controlled to be in an open state.

[0134] In some embodiments, each of the output contactors KT13, KT23, and the positive and negative contactors KT33, KT43 can be controlled to be in an open state individually, while the remaining contactors remain in a closed state, to determine whether the insulation failure fault has been eliminated.

[0135] In other embodiments, the output contactors KT13 and KT23, and the positive and negative contactors KT33 and KT43 of the components can be controlled to be in the open state in pairs or in groups of three, while the remaining contactors remain in the closed state, to determine whether the insulation failure fault has been eliminated.

[0136] In other embodiments, the output contactors KT13 and KT23, and the positive and negative contactors KT33 and KT43 of the components can be controlled to be in the open state in a preset order until all four contactors are in the open state, so as to determine whether the insulation failure fault is eliminated after each control of one contactor to be open.

[0137] It should be noted that since the third high-voltage component B2-1 of system B2 does not have a component positive and negative contactor, the above steps for controlling the component positive and negative contactor to be in the open state are omitted for system B2.

[0138] The process of S106 above, which locates the insulation anomaly of the object to be tested based on the second insulation test value, and obtains the location of the insulation anomaly of the object to be tested, may include: If the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the third high-voltage component of each second type of system, and the location of the contactor in the disconnected state in each second type of system in the wiring harness between the third high-voltage component of each second type of system and the second set of output contactors.

[0139] In this embodiment, in each case where each contactor is controlled to be in the open state, if the corresponding second insulation detection value is greater than or equal to the preset fault threshold, it means that the insulation failure fault is eliminated after the contactor is opened, that is, the previous insulation failure fault is located at the location of the opened contactor.

[0140] Specifically, for the third high-voltage component B1-1, if each of the output contactors KT13, KT23, and the positive and negative contactors KT33, KT43 is individually in the open state, and the corresponding second insulation detection value is greater than or equal to the preset fault threshold, then the insulation fault location is determined to be one of the following locations: the positive wiring harness HV+ where the output contactor KT13 is located, the negative wiring harness HV- where the output contactor KT23 is located, the positive terminal of the third high-voltage component B1-1 where the positive contactor KT33 is located, or the negative terminal of the third high-voltage component B1-1 where the negative contactor KT43 is located.

[0141] If the output contactors KT13 and KT23, and the positive and negative contactors KT33 and KT43 are in the open state in pairs or in groups of three, or if the output contactors KT13 and KT23, and the positive and negative contactors KT33 and KT43 are in the open state in a preset order, and the corresponding second insulation detection value is greater than or equal to the preset fault threshold, then the insulation fault location is the location of all the contactors in the open state.

[0142] Example, Figure 6 The flowchart of the insulation failure detection process for the second type of system provided in the embodiments of this application is as follows: Figure 6 As shown, taking system B1 as an example, this process may include: S401, control input contactors KT01 and KT02 are in the closed state, and all output contactors KT13 and KT23, KT14 and KT24 of the second type system B and the positive and negative contactors KT33 and KT43 of the parts are in the closed state.

[0143] S402. Determine whether the insulation failure fault result is True or False. If it returns True, it is determined that the insulation of the second type system B is normal. If it returns False, then jump to S403.

[0144] S403, All output contactors KT14 and KT24 of control system B2 are in the open state.

[0145] S404. Determine whether the insulation failure fault result is True or False. If it returns True, confirm that the insulation of the third high-voltage component B1-1 is normal. If it returns False, jump to S405.

[0146] S405, The positive contactor KT33 of the control component B1-1 of the third high voltage component is in the open state.

[0147] S406. Determine whether the insulation failure fault result is True or False. If it returns True, confirm that the positive electrode insulation of the third high voltage component B1-1 is abnormal. If it returns False, jump to S407.

[0148] S407. Continue to control the negative contactor KT43 of the third high-voltage component B1-1 to be in the open state.

[0149] S408. Determine whether the insulation failure fault result is True or False. If it returns True, confirm that at least the negative electrode insulation of the third high-voltage component B1-1 is abnormal. If it returns False, jump to S409.

[0150] S409. Continue to control system B1. Output contactor KT13 is in the open state.

[0151] S410. Determine whether the insulation failure fault result is True or False. If it returns True, determine that the positive wire harness HV+ of at least the third high-voltage component B1-1 has an insulation abnormality. If it returns False, determine that the negative wire harness HV- of at least the third high-voltage component B1-1 has an insulation abnormality.

[0152] It should be noted that the above-described procedure for detecting insulation failure in the second type of system is merely an example. Other detection procedures are also within the scope of protection of this solution and will not be elaborated upon here. Specifically, if the third high-voltage component does not have positive and negative contactors, the steps for controlling the positive and negative contactors can be adjusted. By controlling the disconnection of the output contactor, if an insulation failure is detected, the location of the insulation anomaly will be the corresponding wiring harness or the third high-voltage component.

[0153] The insulation failure fault detection method provided in the above embodiments controls the positive and negative contactors and output contactors of the components in each second type of system to be in an open state. Based on the second insulation detection value under the condition that the positive and negative contactors and output contactors of the components are open and the preset fault threshold, the insulation abnormality location of the high-voltage components in each second type of system is determined, thereby achieving accurate location of insulation failure faults.

[0154] In one possible implementation, the third type of system includes at least one, each third type of system including: a third group of output contactors and a second group of high-voltage components, the second group of high-voltage components including: multiple fourth high-voltage components without component positive and negative terminals, the object to be tested is at least one second group of high-voltage components, the target contactor is: all output contactors and all contactors of at least one third type of system, the first state is: the target contactor is in the closed state.

[0155] In this embodiment, as Figure 1 As shown, the third type of system C may include one or more, Figure 1 Two systems are shown. System C1 consists of output contactors KT15 and KT25, and fourth high-voltage components C1-1 and C1-2. System C2 consists of output contactors KT16 and KT26, and fourth high-voltage components C2-1 and C2-2.

[0156] In S101, the object to be tested can be the second group of high-voltage components of all third-class systems. The first input state is that the input contactors KT01 and KT02 are in the closed state, and the output contactors KT15 and KT25, KT16 and KT26 of all third-class systems are in the closed state. If the first insulation detection value detected by the insulation detection circuit is less than the preset insulation threshold, it is determined that there is an insulation abnormality in the second group of high-voltage components of all third-class systems. This insulation abnormality may be an insulation abnormality of the component itself, or it may be an insulation abnormality of the wiring harness between the component and the output contactor (provided that the high-voltage distribution unit has been excluded from having an insulation abnormality).

[0157] In this case, it is necessary to further locate the abnormal location of the insulation failure fault in the third type of system. The method for locating the insulation anomaly is the same for each third type of system; this solution uses... Figure 1 The following explanation uses system C1 as an example.

[0158] If the insulation test result indicates that the object under test has an insulation abnormality, the process of controlling the target contactor to switch to the second state in the above S104 may include: If the insulation test result indicates that at least one of the second group of high-voltage components has an insulation abnormality, for each third type of system, control all contactors in the other third type of systems to be in the open state, and control the fifth output contactor in the third group of output contactors in each third type of system to be in the open state and the sixth output contactor to be in the closed state.

[0159] In this embodiment, if it is determined that there is an insulation abnormality in the second group of high-voltage components of all third-class systems, all other third-class systems except system C1 can be controlled first, for example... Figure 1All output contactors KT16 and KT26 of system C2 are in the open state, while all output contactors KT15 and KT25 of system C1 remain in the closed state. It is determined whether the second insulation detection value is greater than or equal to the preset fault threshold. If the second insulation detection value is greater than or equal to the preset fault threshold, it is determined that the insulation failure faults of all previous third-class systems are not in system C1, and other third-class systems such as system C2 are investigated. If the second insulation detection value is less than the preset fault threshold, it is determined that the previous insulation failure faults are in system C1, and the insulation abnormality location can be further located in system C1.

[0160] Furthermore, if an insulation failure is found in system C1, the insulation failure of the fourth high-voltage component and the wiring harness between the fourth high-voltage component and the output contactor in system C1 will be further investigated.

[0161] Specifically, taking system C1 as an example, in controlling all other third-class systems besides system C1, such as... Figure 1 When all output contactors KT16 and KT26 of system C2 are in the open state, it also controls system C1 to control one of the output contactors KT15 and KT25, for example, KT15, to be in the open state and the other output contactor KT25 to be in the closed state.

[0162] The process of S106 above, which locates the insulation anomaly of the object to be tested based on the second insulation test value, and obtains the location of the insulation anomaly of the object to be tested, may include: If the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be multiple fourth high-voltage components and the wiring harness between them and the fifth output contactor; if the second insulation detection value is less than the preset fault threshold, the insulation abnormality location is determined to be multiple fourth high-voltage components and the wiring harness between them and the sixth output contactor.

[0163] In this embodiment, it is determined whether the second insulation detection value at this time is greater than or equal to the preset fault value. If the second insulation detection value at this time is greater than or equal to the preset fault threshold, the location of the insulation failure fault of all previous third-type systems is determined to be the wiring harness of the output contactor in the open state in system C1 or the fourth high-voltage components C1-1 and C1-2. If the second insulation detection value at this time is less than the preset fault threshold, the location of the insulation failure fault of all previous third-type systems is determined to be the wiring harness of the output contactor in the closed state in system C1 or the fourth high-voltage components C1-1 and C1-2.

[0164] Example, Figure 7 The flowchart of the insulation failure detection process for the third type of system provided in the embodiments of this application is as follows: Figure 7As shown, taking system C1 as an example, this process may also include: S501, control input contactors KT01 and KT02 are in the closed state, and all output contactors KT15 and KT25, KT16 and KT26 of the third type system C are in the closed state.

[0165] S502. Determine whether the insulation failure fault result is True or False. If it returns True, it is determined that the insulation of the third type system C is normal. If it returns False, then jump to S503.

[0166] S503, the output contactors KT16 and KT26 of the control system C2 are in the open state.

[0167] S504. Determine whether the insulation failure fault result is True or False. If it returns True, jump to S505; if it returns False, jump to S506.

[0168] S505. After confirming that there is no insulation abnormality in system C1, further locate the insulation abnormality in system C2.

[0169] S506. It is determined that there is an insulation abnormality in system C1, and further insulation abnormality detection is performed on system C1.

[0170] S507, The output contactor KT15 of the control system C1 is in the open state.

[0171] S508. Determine whether the insulation failure result is True or False. If it returns True, then it is determined that the positive wire harness HV+ of multiple fourth high voltage components or the insulation of multiple fourth high voltage components is abnormal. If it returns False, then it is determined that the negative wire harness HV- of multiple fourth high voltage components or the insulation of multiple fourth high voltage components is abnormal.

[0172] The insulation failure fault detection method provided in the above embodiments controls one output contactor in each third type of system to be in an open state, and determines the insulation abnormality location of the high-voltage component in each third type of system based on the second insulation detection value when one output contactor is open and the preset fault threshold, thereby achieving accurate location of insulation failure faults.

[0173] Except for high-voltage components unrelated to vehicle movement, which can be detected for insulation failure during vehicle operation, the other components can only be detected after the vehicle has stopped. The following explains the specific implementation method for detecting insulation failure during vehicle operation.

[0174] Figure 8 Flowchart of the insulation failure detection method provided in the embodiments of this application Figure 3 ,like Figure 8As shown, the method may further include: S601. If an insulation abnormality alarm is received during operation, the contactor that was most recently closed will be switched to the open state according to the closing sequence of each contactor.

[0175] In this embodiment, after the vehicle is connected to high voltage, the closing states of the input and output contactors in the high-voltage power distribution unit and the working states of the high-voltage components are recorded. The closing sequence of each contactor and the working sequence of the high-voltage components are recorded simultaneously. When an insulation abnormality alarm occurs during vehicle operation due to low insulation value, the most recently closed contactor is switched to the open state according to the closing sequence of each contactor. This causes the high-voltage component connected to the most recently closed contactor to stop working and disables the working enable request of the high-voltage component. This prevents the vehicle controller from switching the working state of the high-voltage components again when performing insulation abnormality detection.

[0176] It should be noted that, to ensure the normal operation of the vehicle, the input contactor is always the first to start. Therefore, the most recently closed contactor is not the input contactor. For high-voltage components with positive and negative contactors, the positive and negative contactors and the connected output contactors may start together or sequentially. However, the high-voltage component will only start working after both the positive and negative contactors and the connected output contactors have started. Therefore, the most recently closed contactor may be the output contactor connected to the high-voltage component or the positive and negative contactors of the high-voltage component. For high-voltage components without positive and negative contactors, the most recently closed contactor can only be the output contactor connected to the high-voltage component.

[0177] S602. If the third insulation detection value after the most recently closed contactor is switched to the open state is less than the preset fault threshold, the component contactor of the high-voltage component of the target type and the output contactor connected to the high-voltage component of the target type are switched to the open state.

[0178] In this embodiment, it is determined whether the third insulation detection value after the most recently closed contactor switches to the open state is greater than or equal to a preset fault threshold. If the third insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the wiring harness or the high-voltage component connected to the most recently closed contactor. The contactor is no longer controlled to close again, so that the corresponding high-voltage component stops working. The vehicle continues to drive and returns to the insulation abnormality location to the user, so that it can be checked and handled after the vehicle has driven.

[0179] If the third insulation detection value is less than the preset fault threshold, and the insulation abnormality is determined to be at another location in the vehicle, then the positive and negative contactors of the target type high-voltage component and the output contactor connected to the target type high-voltage component are switched to the open state. The target type high-voltage component can be a non-vehicle-related high-voltage component, or a non-vehicle-related and non-safety-related high-voltage component, such as a comfort-related high-voltage component, etc. This embodiment does not impose any restrictions on this.

[0180] S603. If the fourth insulation detection value after the contactor of the target type high voltage component and the output contactor connected to the target type high voltage component are switched to the open state is less than the preset fault threshold, control the vehicle to stop and reduce the high voltage.

[0181] In this embodiment, it is determined whether the fourth insulation detection value after the positive and negative contactors of the target type high-voltage component and the output contactor connected to the target type high-voltage component are switched to the open state is greater than or equal to a preset fault threshold. If the fourth insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the target type high-voltage component or the wiring harness connected to the target type high-voltage component. These contactors are no longer controlled to close again, so that the target type high-voltage component stops working. The vehicle continues to drive and returns to the insulation abnormality location to the user, so that it can be checked and handled after the vehicle has driven.

[0182] If the fourth insulation detection value is less than the preset fault threshold, the insulation abnormality location is determined to be the input circuit of the power battery, the power distribution circuit of the high-voltage power distribution unit, or a high-voltage component related to vehicle operation or safety. In this case, the risk of the vehicle continuing to drive is high, and it is necessary to control the vehicle to stop immediately and remove the high voltage. After stopping and removing the high voltage, the above-mentioned S101-S103 and S104-S106 are used to automatically detect and locate the insulation abnormality location.

[0183] The insulation failure detection method provided in the above embodiments can determine whether an insulation failure occurs during vehicle operation and whether the location of the insulation failure affects the vehicle's driving safety. If the location of the insulation failure does not affect the vehicle's driving safety, the vehicle can continue to drive. If the location of the insulation failure does affect the vehicle's driving safety, the user can control the vehicle to stop and reduce the high voltage. This not only reduces the probability of the vehicle stopping due to failure but also improves the reliability and safety of the entire vehicle.

[0184] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for detecting insulation failure, characterized in that, A vehicle controller is applied to a vehicle high-voltage system, the vehicle high-voltage system comprising: a power battery, a high-voltage power distribution unit, and at least one set of high-voltage components; the vehicle controller is respectively connected to an insulation detection circuit, two input contactors, and at least one set of output contactors of the high-voltage power distribution unit; the two ends of the power battery are respectively connected to the insulation detection circuit and the two input contactors; the two input contactors are respectively connected to two output contactors in each set of output contactors via positive and negative wiring harnesses; each set of output contactors is connected to a set of high-voltage components to form a system; the method includes: Based on the object to be tested in the vehicle's high-voltage system, the target contactor is controlled to be in a first state; wherein, the object to be tested is any one of the following: the input circuit of the power battery, the power distribution circuit of the high-voltage power distribution unit, or any one of the at least one set of high-voltage components. The insulation detection circuit obtains the first insulation detection value of the object to be tested within a preset detection period; Based on the first insulation detection value and the preset fault threshold, the insulation detection result is determined, and the insulation detection result is used to indicate whether the object to be tested has an insulation abnormality.

2. The method as described in claim 1, characterized in that, The object to be tested is the input circuit of the power battery, and the target contactor is all input contactors; controlling the target contactor to be in the target state includes: Control all input contactors to be in the off state; The step of determining the insulation detection result based on the first insulation detection value and the preset fault threshold includes: If the first insulation detection value is greater than or equal to the preset fault threshold, the insulation detection result is determined to be that the input circuit insulation of the power battery is normal. If the first insulation detection value is less than the preset fault threshold, the insulation detection result is determined to be an insulation abnormality in the input circuit of the power battery.

3. The method as described in claim 1, characterized in that, The object to be tested is the power distribution circuit of the high-voltage power distribution unit, or the at least one set of high-voltage components; the method further includes: If the insulation test result indicates that the object under test has an insulation abnormality, control the target contactor to switch to the second state; Obtain the second insulation detection value of the object to be tested detected by the insulation detection circuit within a preset detection period; Based on the second insulation detection value, the insulation anomaly location of the object to be tested is determined, thus obtaining the insulation anomaly location of the object to be tested.

4. The method as described in claim 3, characterized in that, The object to be tested is the power distribution circuit of a high-voltage power distribution unit. The target contactors are all input contactors and all output contactors. The first state is that all input contactors are in the closed state and all output contactors are in the open state. If the insulation test result indicates that the object to be tested has an insulation abnormality, the target contactors are controlled to switch to the second state, including: If the insulation test result indicates that the insulation of the power distribution circuit of the high-voltage power distribution unit is abnormal, control each of the input contactors to switch to the open state, while the states of the other contactors remain unchanged. The step of locating the insulation anomaly of the object under test based on the second insulation detection value to obtain the location of the insulation anomaly includes: When any input contactor is in the open state, if the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the power distribution circuit where any input contactor in the high-voltage power distribution unit is located. When all input contactors are in the open state, if the second insulation detection value is less than the preset fault threshold, the insulation abnormality location is determined to be all power distribution circuits of the high-voltage power distribution unit.

5. The method as described in claim 3, characterized in that, The first type of system includes at least one, and each first type of system includes: a first group of output contactors and a first group of high-voltage components. The first group of high-voltage components includes: a first high-voltage component with positive and negative contactors for the components and a second high-voltage component without positive and negative contactors for the components. The object to be tested is at least one first group of high-voltage components. The target contactor is: all input contactors and all contactors of at least one first type of system. The first state is: the target contactor is in a closed state. If the insulation detection result indicates that the object to be tested has an insulation abnormality, controlling the target contactor to switch to the second state includes: If the insulation test result indicates an insulation abnormality in at least one high-voltage component of the first group, for each first type of system, control all contactors in the other first type of systems to be in the open state, and control the positive and negative contactors of the components in each first type of system to be in the open state, while the states of the other contactors remain unchanged. The step of locating the insulation anomaly of the object under test based on the second insulation detection value to obtain the location of the insulation anomaly includes: If the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the first high-voltage component of each first type of system; Otherwise, continue to keep the first output contactor in the first group of output contactors of each first type of system in the open state; If the new second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the wiring harness between the first group of high-voltage components and the first output contactor. If the new second insulation detection value is less than the preset fault threshold, the location of the insulation abnormality is determined to be the wiring harness between the first group of high-voltage components and the second output contactor in the first group of output contactors, or the second high-voltage component.

6. The method as described in claim 3, characterized in that, The second type of system includes at least one, and each second type of system includes: a second group of output contactors and a third high-voltage component, the object to be tested is at least one third high-voltage component, the target contactor is: all input contactors and all contactors of at least one second type of system, the first state is: the target contactor is in a closed state, and if the insulation test result indicates that the object to be tested has an insulation abnormality, controlling the target contactor to switch to the second state includes: If the insulation test result indicates an insulation abnormality in at least one third high-voltage component, for each second-class system, control all contactors in the other second-class systems to be in the open state, and control the third output contactor, the fourth output contactor, the positive contactor and / or the negative contactor in the positive and negative contactors of the second group of output contactors in each second-class system to be in the open state. The step of locating the insulation anomaly of the object under test based on the second insulation detection value to obtain the location of the insulation anomaly includes: If the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the third high-voltage component of each second type of system, and the location of the contactor in the disconnected state in each second type of system in the wiring harness between the third high-voltage component of each second type of system and the second set of output contactors.

7. The method as described in claim 3, characterized in that, The third type of system includes at least one, and each third type of system includes: a third group of output contactors and a second group of high-voltage components. The second group of high-voltage components includes: multiple fourth high-voltage components without contactors for positive and negative poles. The object to be tested is at least one of the second group of high-voltage components. The target contactor is: all output contactors and all contactors of at least one third type of system. The first state is: the target contactor is in a closed state. If the insulation detection result indicates that the object to be tested has an insulation abnormality, controlling the target contactor to switch to the second state includes: If the insulation test result indicates an insulation abnormality of at least one second group of high-voltage components, for each third type of system, control all contactors in the other third type of systems to be in the open state, and control the fifth output contactor in the third group of output contactors in each third type of system to be in the open state and the sixth output contactor to be in the closed state. The step of locating the insulation anomaly of the object under test based on the second insulation detection value to obtain the location of the insulation anomaly includes: If the second insulation detection value is greater than or equal to the preset fault threshold, the insulation abnormality location is determined to be the plurality of fourth high-voltage components, or the wiring harness between the plurality of fourth high-voltage components and the fifth output contactor; If the second insulation detection value is less than the preset fault threshold, the insulation abnormality location is determined to be one of the plurality of fourth high-voltage components, or the wiring harness between the plurality of fourth high-voltage components and the sixth output contactor.

8. The method as described in claim 1, characterized in that, The method further includes: If an insulation abnormality alarm is received during operation, the contactor that was most recently closed will be switched to the open state according to the closing sequence of each contactor. If the third insulation detection value after the most recently closed contactor is switched to the open state is less than the preset fault threshold, the component contactor of the high-voltage component of the target type and the output contactor connected to the high-voltage component of the target type are switched to the open state. If the fourth insulation detection value after the contactor of the high-voltage component of the target type and the output contactor connected to the high-voltage component of the target type are switched to the open state is less than the preset fault threshold, the vehicle is controlled to stop and the high voltage is reduced.

9. A vehicle high-voltage system, characterized in that, The vehicle high-voltage system includes: a power battery, a high-voltage power distribution unit, and at least one set of high-voltage components; the high-voltage power distribution unit includes: an insulation detection circuit, two input contactors, and at least one set of output contactors; the two ends of the power battery are respectively connected to the insulation detection circuit and the two input contactors; the two input contactors are respectively connected to two output contactors in each set of output contactors via positive and negative wiring harnesses; each set of output contactors is connected to a set of high-voltage components to form a system; the vehicle controller is respectively connected to the insulation detection circuit, the two input contactors, and the at least one set of output contactors; the vehicle controller is used to execute the insulation failure fault detection method as described in any one of claims 1-8.

10. The vehicle high-voltage system as described in claim 9, characterized in that, The system includes: a first type of system, a second type of system and a third type of system, wherein a first high-voltage component with a component positive and negative contactor and a second high-voltage component without a component positive and negative contactor, together with a set of output contactors, constitute a first type of system; The third high-voltage component and a set of output contactors form a second type of system; A third type of system is formed by multiple fourth high-voltage components without positive and negative contactors and a set of output contactors.

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