Insulation fault location apparatus, method and system, medium, controller, and vehicle

Abstract

An insulation fault location apparatus, method and system, a medium, a controller, and a vehicle. The apparatus comprises: an insulation detection circuit; a first switching circuit, connected to the insulation detection circuit, adapted to be connected to a battery pack, and configured to enable the insulation detection circuit and the battery pack to form a first insulation detection loop; and a second switching circuit, adapted to be separately connected to the battery pack and a load, and configured to enable the load and the battery pack to form a load power loop.

Description

Insulation fault location devices, methods and media, controllers, systems, and vehicles

[0001] Cross-references to related applications

[0002] This application is based on and claims priority to Chinese Patent Application No. 202510353332.6, filed on March 24, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of automotive insulation testing technology, and more specifically, to an insulation fault location device, method, medium, controller, system, and vehicle. Background Technology

[0004] Insulation testing is crucial for the safety, reliability, performance, and compliance of electric vehicles and is a key measure to ensure safe vehicle operation. Summary of the Invention

[0005] This application aims to at least partially address one of the technical problems in the related art. To this end, one objective of this application is to provide an insulation fault location device that, while achieving insulation fault location, also possesses the advantages of low cost and simple and flexible implementation.

[0006] The second objective of this application is to propose a method for locating insulation faults.

[0007] The third objective of this application is to provide a computer-readable storage medium.

[0008] The fourth objective of this application is to propose a controller.

[0009] The fifth objective of this application is to provide an insulation fault location system.

[0010] The sixth objective of this application is to propose a vehicle.

[0011] To achieve the above objectives, a first aspect of this application provides an insulation fault location device, the device comprising: an insulation detection circuit; a first switching circuit connected to the insulation detection circuit and used to connect a battery pack, configured to enable the insulation detection circuit and the battery pack to form a first insulation detection circuit; and a second switching circuit used to connect the battery pack and a load respectively, configured to enable the load and the battery pack to form a load power circuit.

[0012] An insulation fault location device according to some embodiments of this application is provided with a first switching circuit connected between the insulation detection circuit and the battery pack, and a second switching circuit connected between the battery pack and the load. By controlling the on / off state of the first and second switching circuits, the insulation detection circuit, the battery pack, and the load are controlled to form different insulation detection loops. While realizing insulation fault location, it also has the advantages of low cost and simple and flexible implementation.

[0013] To achieve the above objectives, a second aspect of this application provides an insulation fault location method for an insulation fault location device. The insulation fault location device includes an insulation detection circuit, a first switching circuit, and a second switching circuit. The first switching circuit is used to connect the insulation detection circuit and a battery pack, and the second switching circuit is used to connect the battery pack and a load. The method includes: controlling the first switching circuit to conduct, so that the insulation detection circuit and the battery pack form a first insulation detection loop, and locating battery insulation anomalies based on the first insulation detection loop.

[0014] According to some embodiments of the insulation fault location method of this application, by controlling the first switch circuit to be turned on and the second switch circuit to be turned on, the insulation detection circuit forms corresponding insulation detection loops with the battery pack and the load respectively, thereby realizing insulation detection and location of the battery pack and the load. It has the advantages of simpler and more flexible implementation.

[0015] To achieve the above objectives, a third aspect of this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the insulation fault location method as proposed in the second aspect of this application.

[0016] To achieve the above objectives, a fourth aspect of this application provides a controller, including a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, it implements the insulation fault location method as proposed in the second aspect of this application.

[0017] To achieve the above objectives, a fifth aspect of this application provides an insulation fault location system, including an insulation fault location device as provided in the first aspect of this application, or a controller as provided in the fourth aspect of this application.

[0018] To achieve the above objectives, a sixth aspect of this application provides a vehicle including an insulation fault location system as described in the fifth aspect of this application.

[0019] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0020] Figure 1 is a schematic diagram of an insulation fault location device according to some embodiments of this application;

[0021] Figure 2 is a schematic diagram of an insulation fault location device according to some embodiments of this application;

[0022] Figure 3 is a schematic diagram of an insulation fault location device according to some embodiments of this application;

[0023] Figure 4 is a schematic diagram of the connection between the auxiliary power supply and the bus capacitor in some embodiments of this application;

[0024] Figure 5 is a schematic diagram of a motor-corresponding three-phase inverter according to some embodiments of this application;

[0025] Figure 6 is a schematic diagram of an insulation detection circuit according to some embodiments of this application;

[0026] Figure 7 is a flowchart of an insulation fault location method according to some embodiments of this application;

[0027] Figure 8 is a flowchart of an insulation fault location method according to some embodiments of this application;

[0028] Figure 9 is a flowchart of an insulation fault location method according to some embodiments of this application;

[0029] Figure 10 is a flowchart of an insulation fault location method according to some embodiments of this application;

[0030] Figure 11 is a flowchart of an insulation fault location method according to some specific embodiments of this application;

[0031] Figure 12 is a structural block diagram of a controller according to some embodiments of this application;

[0032] Figure 13 is a structural block diagram of an insulation fault location system according to some embodiments of this application;

[0033] Figure 14 is a structural block diagram of an insulation fault location system according to some embodiments of this application;

[0034] Figure 15 is a schematic diagram of a vehicle according to some embodiments of this application. Embodiments of the present invention

[0035] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0036] The insulation fault location device, method, medium, controller, system, and vehicle of this application will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] In related technologies, when locating insulation faults in electric vehicles, these technologies can only detect the battery end and the high-voltage load end simultaneously, and cannot achieve single-end insulation detection. Furthermore, they are costly and complex to operate.

[0038] Figure 1 is a schematic diagram of an insulation fault location device according to an embodiment of this application. As shown in Figure 1, the insulation fault location device may include:

[0039] Insulation detection circuit;

[0040] A first switching circuit, connected to an insulation detection circuit and used to connect a battery pack, is configured to make the insulation detection circuit and the battery pack form a first insulation detection loop.

[0041] The second switching circuit, used to connect the battery pack and the load respectively, is configured to make the load and the battery pack form a load power circuit.

[0042] To reduce costs while achieving insulation fault location, the insulation fault location device in this application embodiment includes a first switching circuit and a second switching circuit. The first switching circuit is connected between the insulation detection circuit and the battery pack, and the second switching circuit is connected between the battery pack and the load.

[0043] In this embodiment of the application, by controlling the on / off state of the first switch circuit and the second switch, the insulation detection circuit and the battery pack are combined to form a first insulation detection circuit, so as to realize single-end insulation detection of the battery pack.

[0044] In some embodiments, when the first switching circuit is on and the second switching circuit is off, the insulation detection circuit and the battery pack can form a first insulation detection circuit. Since the insulation detection circuit in the first insulation detection circuit is directly connected to the battery terminals, it can detect the insulation resistance values ​​Rp1 and Rn1 of the positive / negative terminals of the battery pack to the vehicle ground. Based on these insulation resistance values, it can be determined whether the battery pack is faulty. In some embodiments, if either the insulation resistance value Rp1 or Rn1 of the positive / negative terminals of the battery pack to the vehicle ground is less than a first preset threshold, the battery pack insulation is determined to be abnormal. Otherwise, the battery pack insulation is determined to be normal.

[0045] In one embodiment of this application, the second switching circuit is further configured to, together with the first switching circuit, form a second insulation detection loop with the load.

[0046] In this embodiment of the application, by controlling the on / off state of the first and second switching circuits, the insulation detection circuit and the load are combined to form a second insulation detection circuit, thereby realizing the insulation detection of the load.

[0047] In some embodiments, when the first switching circuit is on and the second switching circuit is on, the insulation detection circuit and the load form a second insulation detection circuit. Since the insulation detection circuit in the second insulation detection circuit is not directly connected to the load side, the battery pack is connected in parallel with the load in the second insulation detection circuit. Therefore, the insulation detection circuit in the second insulation detection circuit detects the insulation resistance values ​​Rp1' and Rn1' of the vehicle's DC high voltage positive / negative terminals to the vehicle ground. Based on the insulation resistance values ​​Rp1' and Rn1' detected by the insulation detection circuit in the second insulation detection circuit and the insulation resistance values ​​Rp1 and Rn1 detected by the insulation detection circuit in the first insulation detection circuit, the insulation resistance values ​​Rp2 and Rn2 of the load's positive / negative bus to the vehicle ground can be calculated. Whether the load has a fault can be determined based on the insulation resistance values ​​Rp2 and Rn2 of the load's positive / negative bus to the vehicle ground. In some embodiments, if either the insulation resistance Rp2 or the insulation resistance Rn2 of the positive / negative busbar of the load to the vehicle ground is less than a second preset threshold, the load insulation is determined to be abnormal. Otherwise, the load insulation is determined to be normal.

[0048] The insulation fault location device in this embodiment of the application is provided with a first switching circuit connected between the insulation detection circuit and the battery pack, and a second switching circuit connected between the battery pack and the load. By controlling the on and off of the first switching circuit and the second switching circuit, the insulation detection circuit, the battery pack and the load are controlled to form different insulation detection loops, thereby realizing insulation fault location.

[0049] In one embodiment of this application, as shown in FIG1, the first switching circuit may include:

[0050] The first switch K1 has its first end connected to the first end of the insulation detection circuit, and its second end connected to the positive terminal of the battery pack.

[0051] The second switch K2 has its first end connected to the second end of the insulation detection circuit, and its second end connected to the negative terminal of the battery pack.

[0052] In some embodiments, the first switching circuit may include a first switch K1 and a second switch K2. The first switch K1 is connected between the positive terminal of the battery pack and a first terminal of the insulation detection circuit, and the second switch K2 is connected between the negative terminal of the battery pack and a second terminal of the insulation detection circuit. Therefore, when the first switching circuit is turned on, the first switch K1 and the second switch K2 are closed. When the first switching circuit is turned off, the first switch K1 and the second switch K2 are open.

[0053] In one embodiment of this application, as shown in FIG1, the second switching circuit may include:

[0054] The third switch K3 has its first terminal connected to the positive terminal of the battery pack and its second terminal connected to the input terminal of the load.

[0055] The fourth switch K4 has its first terminal connected to the negative terminal of the battery pack and its second terminal connected to the output terminal of the load.

[0056] In some embodiments, the second switching circuit may include a third switch K3 and a fourth switch K4. The third switch K3 is connected between the positive terminal of the battery pack and the input terminal of the load, and the fourth switch K4 is connected between the negative terminal of the battery pack and the output terminal of the load. Therefore, when the second switching circuit is turned on, the third switch K3 and the fourth switch K4 are closed. When the second switching circuit is turned off, the third switch K3 and the fourth switch K4 are open.

[0057] It should be noted that, since the insulation detection circuit in the second insulation detection circuit is not directly connected to the load, calculations are required based on the insulation resistance values ​​detected by the insulation detection circuit in the second and first insulation detection circuits to determine whether the load has an insulation abnormality. Therefore, the insulation fault location device in this embodiment is equipped with a third switching circuit connected between the insulation detection circuit and the load, so as to directly determine the load insulation abnormality using the insulation detection circuit.

[0058] In one embodiment of this application, as shown in FIG2, the insulation fault location device may further include:

[0059] The third switching circuit is connected to the insulation detection circuit and is used to connect the load. Together with the first and second switching circuits, it is configured to form a third insulation detection loop with the insulation detection circuit and the load.

[0060] In some embodiments, when performing insulation fault detection on the load, the first and second switching circuits are disconnected, and the third switching circuit is closed, forming a third insulation detection circuit with the load. The insulation detection circuit in the third insulation detection circuit is directly connected to the load terminal; therefore, it can detect the insulation resistance values ​​Rp2 and Rn2 of the load's positive / negative busbars to the vehicle ground. Based on these values, it can be determined whether the load has a fault. In some embodiments, if either Rp2 or Rn2 is less than a second preset threshold, the load is determined to have an insulation fault. Otherwise, the load is determined to have normal insulation.

[0061] In one embodiment of this application, as shown in FIG2, the third switching circuit may include:

[0062] The fifth switch K5 has its first terminal connected to the first terminal of the insulation detection circuit, and its second terminal connected to the input terminal of the load.

[0063] The sixth switch K6 has its first terminal connected to the second terminal of the insulation detection circuit, and its second terminal connected to the output terminal of the load.

[0064] In some embodiments, the third switching circuit may include a fifth switch K5 and a sixth switch K6. The fifth switch K5 is connected between the first terminal of the insulation detection circuit and the input terminal of the load, and the sixth switch K6 is connected between the second terminal of the insulation detection circuit and the output terminal of the load. Therefore, when the third switching circuit is turned on, the fifth switch K5 and the sixth switch K6 are closed. When the third switching circuit is turned off, the fifth switch K5 and the sixth switch K6 are open.

[0065] It should be noted that, since the first switching circuit connects the insulation detection circuit and the battery pack, and the second switching circuit connects the battery pack and the load, and the insulation detection circuit also connects to the load, to form a third insulation detection circuit with the load, the first and second switching circuits need to be disconnected, and the third switching circuit closed. Therefore, the insulation detection circuit and the load forming the third insulation detection circuit are in a powered-off state.

[0066] The insulation fault location device in this embodiment of the application is equipped with a bus capacitor C1. When the battery pack is disconnected from the load circuit (when the second switching circuit is disconnected), the electrical energy stored in the bus capacitor C1 supplies power to the insulation detection circuit and the load to form a third insulation detection circuit, thereby realizing power-off insulation detection.

[0067] In one embodiment of this application, as shown in FIG3, the insulation fault location device may further include:

[0068] The bus capacitor C1, which is connected to the battery pack and the load respectively, is configured to provide a detection voltage to the insulation detection circuit and the load to form a third insulation detection loop.

[0069] In some embodiments, the electrical energy stored in the bus capacitor C1 is used to provide a detection voltage to the third insulation detection circuit formed by the insulation detection circuit and the load. There are two ways to do this:

[0070] The first method is to enter active discharge mode when the battery pack is disconnected from the load circuit (when the second switching circuit is disconnected). When the voltage stored on the bus capacitor C1 drops to 60V, the active discharge mode is exited. The insulation monitoring function is achieved by using the 60V on the bus capacitor C1 during the slow decrease.

[0071] The second method is to prevent the battery pack from entering the active discharge mode when it is disconnected from the load circuit (when the second switch circuit is disconnected), so that the high voltage stored on the bus capacitor C1 is discharged through the passive discharge mode, and the voltage achieves the insulation monitoring function during the passive discharge process.

[0072] The insulation fault location device in this embodiment is also equipped with an auxiliary power supply, which can also be used to supply power to the bus capacitor, so as to supply power to the insulation detection circuit and the load to form a third insulation detection circuit, thereby realizing power-off insulation detection.

[0073] In one embodiment of this application, as shown in FIG3, the insulation fault location device may further include: an auxiliary power supply connected to the bus capacitor and configured to supply power to the bus capacitor.

[0074] In some embodiments, when the battery pack is disconnected from the load circuit (when the second switching circuit is disconnected), an auxiliary power supply can be used to charge the bus capacitor C1 to provide voltage to the insulation detection circuit and realize the insulation monitoring function.

[0075] In one specific embodiment of this application, as shown in FIG4, the auxiliary power supply includes a battery and a DC-DC converter, and the battery is connected to the bus capacitor through the DC-DC converter.

[0076] In this embodiment, the bus capacitor is pre-charged in reverse using a battery and a DC-DC converter.

[0077] In some embodiments, the DC-DC converter draws power from a low-voltage battery, boosts the voltage from the low-voltage battery to a high voltage equal to the battery pack voltage, and then charges the bus capacitor C1. The charged bus capacitor C1 then provides a detection voltage to the insulation detection circuit and the load, forming a third insulation detection loop.

[0078] In one specific embodiment of this application, as shown in FIG4, the auxiliary power supply includes an AC-DC (Alternating Current to Direct Current) inverter and a generator. The generator is connected to the bus capacitor through the AC-DC inverter, wherein the generator uses an engine to generate electricity.

[0079] In this embodiment, an AC-DC inverter and a generator are used to supply power to the bus capacitor.

[0080] In some embodiments, a gasoline-powered engine can be used to drive a generator, and an AC-DC inverter can convert alternating current into high-voltage direct current to charge the bus capacitor C1, thereby providing detection voltage to the third insulation detection circuit formed by the insulation detection circuit and the load.

[0081] When the insulation fault location device in this application embodiment is used in a vehicle, it can control the vehicle to supply power to the bus capacitor using strategies such as active discharge function, passive discharge function, reverse pre-charge function, and voltage stabilization function, so as to realize the insulation detection function when the power is off.

[0082] In one embodiment of this application, the load includes a motor and a three-phase inverter. The DC terminal of the three-phase inverter is connected to the bus capacitor, and the AC terminal of the three-phase inverter is connected to the motor. The upper and lower bridge arm switches of any phase arm of the three-phase inverter are configured to form a fourth insulation detection circuit with the motor.

[0083] As shown in Figure 5, S1, S2, and S3 in the three-phase inverter correspond to the upper bridge arm switches, and S4, S5, and S6 are the lower bridge arm switches. Ra, Rb, and Rc represent the insulation resistances of each phase of the motor relative to the casing. By closing the upper or lower bridge arm switch of any phase in the three-phase inverter, the insulation detection circuit and the motor can form a fourth insulation detection circuit. Based on the insulation resistance value detected by the insulation detection circuit in the fourth insulation detection circuit, the insulation resistance value Rm of the motor can be calculated.

[0084] In some embodiments, the first and second switching circuits are disconnected, the third switching circuit is closed, and the upper or lower bridge arm switch of any phase bridge arm in the three-phase inverter is closed, forming a fourth insulation detection circuit with the motor. At this time, the load and the motor are simultaneously connected to the insulation detection circuit. Therefore, the insulation detection circuit in the fourth insulation detection circuit detects the insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative terminals to the vehicle ground. The insulation resistance value Rm of the motor can be calculated based on these values. Specifically, when calculating the motor's insulation resistance value Rm, in response to closing the upper bridge arm switch, the insulation resistance value Rm can be calculated using the formula Rm=Rp2*Rp2' / (Rp2-Rp2') based on the insulation resistance values ​​Rp2 and Rp2'. In response to the closing of the upper bridge arm switch, the insulation resistance value Rm of the motor can be calculated using the formula Rm=Rp2*Rp2' / (Rp2-Rp2') based on the insulation resistance values ​​Rp2 and Rp2'.

[0085] The presence or absence of a motor fault can be determined based on the motor's insulation resistance value Rm. In some embodiments, if the motor's insulation resistance value Rm is less than a third preset threshold, then the motor insulation is determined to be abnormal. Otherwise, the motor insulation is determined to be normal.

[0086] In one embodiment of this application, the motor includes at least one of an electric compressor, a drive motor, and a generator.

[0087] The motor in this application embodiment can be a motor in electronic equipment such as an electric compressor, drive motor, or generator. The electric compressor, drive motor, generator, and other electronic equipment all use a three-phase inverter to control the motor's operation. This application does not limit the electronic equipment in which the motor is located.

[0088] It should be noted that when performing insulation testing on the motor in the generator, the generator is not used to charge the bus capacitor.

[0089] In one embodiment of this application, the insulation detection circuit employs an unbalanced bridge insulation detection circuit.

[0090] In one specific embodiment of this application, as shown in FIG6, the insulation detection circuit may include a first resistor R1, a second resistor R2, a third resistor R3, a sampling resistor R4, and a seventh switch K7. The first end of the first resistor R1 is connected to the first end of the insulation detection circuit. The second end of the first resistor R1 is connected to the first end of the second resistor R2 to form a first node. The first node is connected to the first end of the seventh switch K7. The second end of the seventh switch K7 is connected to the second end of the insulation detection circuit. The second end of the second resistor R2 is connected to the first end of the third resistor R3 to form a second node. The second node is grounded. The second end of the third resistor R3 is connected to the first end of the sampling resistor R4. The first end of the sampling resistor R4 is connected to the voltage sampling module. The second end of the sampling resistor R4 is connected to the second end of the insulation detection circuit.

[0091] In some embodiments, the unbalanced bridge insulation detection circuit consists of a first resistor R1, a second resistor R2, a third resistor R3, a sampling resistor R4, and a seventh switch K7. U4 is the voltage across the sampling resistor R4.

[0092] The detection principle of the unbalanced bridge insulation detection circuit is as follows: When insulation detection is performed, control K9 is turned off, and the voltage U4 across sampling resistor R4 is acquired, resulting in a voltage value V1. Then, control K9 is closed, breaking the original balanced bridge and redistributing the voltage. The voltage U4 across sampling resistor R4 is acquired again, yielding another voltage value V2. Based on voltage values ​​V1 and V2, the voltages U1 and U2 of the positive / negative terminals of the tested object relative to GND (Ground) before and after K9 is closed are calculated. Substituting these parameters into the insulation resistance calculation formula, the insulation resistance value of the positive / negative terminals of the tested object relative to GND can be obtained:

[0093] Formula 1: Rp=(R4*(R2^2*U0*U1-R2^2*U0*U2+R1*R2*U0*U1-R1*R2*U0*U2)) / (R2^2 *U1*V2-R2^2*U2*V1+R1*R4*U1*U2+R2*R4*U0*U2+R1*R2*U1*V2-R1*R2*U2*V1)

[0094] Formula 2:

[0095] Rn=(R2^2*R4*U0*U1-R2^2*R4*U0*U2+R1*R2*R4*U0*U1-R1*R2*R4*U0*U2) / (R2*R4*U0^2-R2^2*U0*V1+R2^2*U0*V2-R2^2* U1*V2+R2^2*U2*V1+R1*R4*U0*U2-R1*R4*U0*U1-R1*R4*U1*U2-R1*R2*U0*V1+R1*R2*U0*V2-R1*R2*U1*V2+R1*R2*U2*V1)]

[0096] In the formula, Rp is the insulation resistance between the positive terminal of the object being tested and GND, Rn is the insulation resistance between the negative terminal of the object being tested and GND, and U0 is the voltage between the positive and negative terminals of the object being tested. The value of U0 can be obtained by closing the eighth switch K8 in Figure 6, based on the resistance of R0.

[0097] Therefore, when the insulation detection circuit and the battery pack form the first insulation detection circuit, the insulation resistance values ​​Rp1 and Rn1 of the positive / negative terminals of the battery pack to the vehicle ground can be calculated by closing the seventh switch K7. When the insulation detection circuit and the load form the third insulation detection circuit, the insulation resistance values ​​Rp2 and Rn2 of the positive / negative busbars of the load to the vehicle ground can be calculated by closing the seventh switch K7.

[0098] It should be noted that the embodiments of this application do not limit the form of the insulation detection circuit, and other forms of insulation detection circuits may also be used.

[0099] It should be noted that the first, second, and third preset thresholds are defined by each OEM. For example, the first and second preset thresholds are set to 500Ω / V according to relevant regulations.

[0100] It should be noted that when the insulation fault location device in this embodiment is implemented on a vehicle, a main positive contactor and a main negative contactor are provided between the vehicle's battery pack and the load. The main positive contactor can be used as the main positive contactor, and the main negative contactor can be used as the fourth switch K4.

[0101] The insulation fault location device of this application embodiment, by adding a first switching circuit that connects the insulation detection circuit to the battery pack end and a third switching circuit that connects the insulation detection circuit to the high-voltage load end, can simultaneously realize insulation monitoring functions at both ends of the battery and the load. Furthermore, when using the insulation fault location device for insulation location, it also has the advantage of a simpler and more flexible implementation method.

[0102] This application provides a method for locating insulation faults.

[0103] The insulation fault location method of this application embodiment is used in an insulation fault location device. The insulation fault location device includes an insulation detection circuit, a first switch circuit, and a second switch circuit. The first switch circuit is used to connect the insulation detection circuit and the battery pack, and the second switch circuit is used to connect the battery pack and the load.

[0104] In this embodiment, the first switching circuit is connected between the insulation detection circuit and the battery pack, and the second switching circuit is connected between the battery pack and the load.

[0105] Figure 7 is a flowchart of an insulation fault location method according to an embodiment of this application. As shown in Figure 7, the insulation fault location method may include:

[0106] S101, control the first switch circuit to turn on, so that the insulation detection circuit and the battery pack form a first insulation detection circuit, and locate the battery insulation abnormality based on the first insulation detection circuit.

[0107] In some embodiments, when the first switching circuit is turned on, it connects the insulation detection circuit and the battery pack to form a first insulation detection circuit. The insulation detection circuit in the first insulation detection circuit is directly connected to the battery terminal. The insulation detection circuit can detect the insulation resistance values ​​Rp1 and Rn1 of the positive / negative terminals of the battery pack to the vehicle ground. Based on the insulation resistance values ​​Rp1 and Rn1 of the positive / negative terminals of the battery pack to the vehicle ground, it can be determined whether the battery pack has an insulation abnormality.

[0108] In one embodiment of this application, battery insulation anomaly location is performed based on a first insulation detection circuit, including:

[0109] If either the insulation resistance value Rp1 or the insulation resistance value Rn1 of the battery pack's positive / negative terminals to the vehicle ground, detected by the insulation detection circuit in the first insulation detection circuit, is less than a first preset threshold, then the battery pack insulation is determined to be abnormal.

[0110] In some embodiments, if either the insulation resistance Rp1 or the insulation resistance Rn1 between the positive / negative terminals of the battery pack and the vehicle ground is less than a first preset threshold, then the battery pack insulation is determined to be abnormal. Otherwise, the battery pack insulation is determined to be normal.

[0111] In one embodiment of this application, as shown in FIG8, the insulation fault location method may include:

[0112] S102 controls the second switching circuit to turn on, so that the insulation detection circuit and the load form a second insulation detection loop, and performs load insulation abnormality location based on the second insulation detection loop.

[0113] In some embodiments, when the second switching circuit (high voltage on the vehicle) is turned on, i.e., the first switching circuit is turned on, and the second switching circuit is turned on, the insulation detection circuit and the load form a second insulation detection loop. Since the insulation detection circuit in the second insulation detection loop is not directly connected to the load side, the battery pack is connected in parallel with the load in the second insulation detection loop. Therefore, based on the insulation resistance values ​​detected by the insulation detection circuit in the second insulation detection loop and the insulation resistance values ​​detected by the insulation detection circuit in the first insulation detection loop, the insulation resistance values ​​Rp2 and Rn2 of the positive / negative busbars of the load to the vehicle ground can be calculated. Based on the insulation resistance values ​​Rp2 and Rn2 of the positive / negative busbars of the load to the vehicle ground, it can be determined whether the load has an insulation abnormality.

[0114] In one embodiment of this application, load insulation anomaly location is performed based on a second insulation detection circuit, including:

[0115] Based on the insulation resistance values ​​Rp1' and Rn1' of the positive / negative DC high voltage poles of the vehicle to the vehicle body ground, as well as the insulation resistance values ​​Rp1 and Rn1, obtained by the insulation detection circuit in the second insulation detection circuit, calculate the insulation resistance values ​​Rp2 and Rn2 of the positive / negative busbars of the load to the vehicle body ground.

[0116] If either the insulation resistance value Rp2 or the insulation resistance value Rn2 is less than a second preset threshold, then the load insulation is determined to be abnormal.

[0117] In some embodiments, the insulation detection circuit in the second insulation detection circuit detects the insulation resistance values ​​Rp1' and Rn1' of the vehicle's DC high voltage positive / negative terminals to the vehicle body ground. The insulation resistance values ​​Rp1' and Rn1' of the vehicle's DC high voltage positive / negative terminals to the vehicle body ground detected by the insulation detection circuit in the second insulation detection circuit can be stored. Based on the insulation resistance values ​​Rp1 and Rn1 of the battery pack's positive / negative terminals to the vehicle body ground detected by the insulation detection circuit in the first insulation detection circuit, the insulation resistance values ​​Rp2 and Rn2 of the load's positive / negative busbars to the vehicle body ground can be calculated.

[0118] Specifically, when calculating the insulation resistance Rp2, it can be calculated using the formula Rp2=Rp1*Rp1' / (Rp1-Rp1') based on the insulation resistances Rp1 and Rp1'. Similarly, when calculating the insulation resistance Rn2, it can be calculated using the formula Rn2=Rn1*Rn1' / (Rn1-Rn1') based on the insulation resistances Rn1 and Rn1'.

[0119] If either the insulation resistance Rp2 or the insulation resistance Rn2 of the positive / negative busbar of the load to the vehicle ground is less than a second preset threshold, the load insulation is determined to be abnormal. Otherwise, the load insulation is determined to be normal.

[0120] In one embodiment of this application, the insulation fault location device includes a third switching circuit for connecting the insulation detection circuit and the load.

[0121] In this embodiment, the third switching circuit is connected between the insulation detection circuit and the load.

[0122] In one embodiment of this application, as shown in FIG9, the insulation fault location method may further include:

[0123] S103 controls the first and second switching circuits to turn off and the third switching circuit to turn on, so that the insulation detection circuit and the load form a third insulation detection loop, and the load insulation abnormality is located based on the third insulation detection loop.

[0124] In some embodiments, when performing insulation fault detection on the load, the first and second switching circuits are turned off, and the third switching circuit is closed, so that the insulation detection circuit and the load form a third insulation detection loop. The insulation detection circuit in the third insulation detection loop is directly connected to the load terminal; therefore, the insulation detection circuit in the third insulation detection loop can detect the insulation resistance values ​​Rp2 and Rn2 of the positive / negative busbars of the load to the vehicle ground. Based on the insulation resistance values ​​Rp2 and Rn2 of the positive / negative busbars of the load to the vehicle ground, it can be determined whether the load has malfunctioned.

[0125] In one embodiment of this application, load insulation anomaly location based on a third insulation detection circuit includes:

[0126] If either the insulation resistance value Rp2 or the insulation resistance value Rn2 of the positive / negative busbar of the load to the vehicle body ground, detected by the insulation detection circuit in the third insulation detection circuit, is less than the second preset threshold, then the load insulation is determined to be abnormal.

[0127] In some embodiments, if either the insulation resistance Rp2 or the insulation resistance Rn2 of the positive / negative busbar of the load to the vehicle ground is less than a second preset threshold, the load insulation is determined to be abnormal. Otherwise, the load insulation is determined to be normal.

[0128] It should be noted that, since the first switching circuit connects the insulation detection circuit and the battery pack, and the second switching circuit connects the battery pack and the load, and the insulation detection circuit also connects to the load, to form a third insulation detection circuit with the load, the first and second switching circuits need to be disconnected, and the third switching circuit closed. Therefore, the insulation detection circuit and the load forming the third insulation detection circuit are in a powered-off state.

[0129] In one embodiment of this application, the insulation fault location device may include a bus capacitor connected to the battery pack and the load respectively. The insulation fault location method further includes: when the second switching circuit is turned off, using the bus capacitor to provide a detection voltage to the insulation detection circuit and the load to form a third insulation detection circuit.

[0130] To enable load insulation anomaly location based on the third insulation detection circuit, when the second switching circuit is disconnected, the electrical energy stored in the bus capacitor C1 can supply power to the insulation detection circuit and the load to form the third insulation detection circuit, thereby achieving power-off insulation detection.

[0131] In some embodiments, the electrical energy stored in the bus capacitor C1 is used to provide a detection voltage to the third insulation detection circuit formed by the insulation detection circuit and the load. There are two ways to do this:

[0132] The first method is to enter active discharge mode when the battery pack is disconnected from the load circuit (when the second switching circuit is disconnected). When the voltage stored on the bus capacitor C1 drops to 60V, the active discharge mode is exited. The insulation monitoring function is achieved by using the 60V on the bus capacitor C1 during the slow decrease.

[0133] The second method is to prevent the battery pack from entering the active discharge mode when it is disconnected from the load circuit (when the second switch circuit is disconnected), so that the high voltage stored on the bus capacitor C1 is discharged through the passive discharge mode, and the voltage achieves the insulation monitoring function during the passive discharge process.

[0134] In addition to utilizing the active discharge mode and passive discharge mode when the battery pack is disconnected from the load circuit, this application embodiment can also utilize an auxiliary power supply to power the bus capacitor to achieve power-off insulation detection.

[0135] In one embodiment of this application, the insulation fault location device includes an auxiliary power supply that can be connected to the bus capacitor, and the insulation fault location method further includes: controlling the auxiliary power supply to supply power to the bus capacitor.

[0136] In some embodiments, the auxiliary power supply can be controlled to supply power to the bus capacitor, so that the bus capacitor C1 supplies power to the insulation detection circuit and the load to form a third insulation detection circuit, thereby realizing power-off insulation detection.

[0137] In one specific embodiment of this application, the auxiliary power supply may include a battery and a DC-DC converter, with the battery connected to the bus capacitor via the DC-DC converter.

[0138] In this embodiment, the bus capacitor is pre-charged in reverse using a battery and a DC-DC converter.

[0139] In some embodiments, the DC-DC converter draws power from a low-voltage battery, boosts the voltage from the low-voltage battery to a high voltage equal to the battery pack voltage, and then charges the bus capacitor C1. The charged bus capacitor C1 then provides a detection voltage to the insulation detection circuit and the load, forming a third insulation detection loop.

[0140] In one specific embodiment of this application, the auxiliary power supply may include an AC-DC inverter and a generator, wherein the generator is connected to the bus capacitor through the AC-DC inverter, and the generator uses an engine to generate electricity.

[0141] In this embodiment, an AC-DC inverter and a generator are used to supply power to the bus capacitor.

[0142] In some embodiments, a gasoline-powered engine can be used to drive a generator, and an AC-DC inverter can convert alternating current into high-voltage direct current to charge the bus capacitor C1, thereby providing detection voltage to the third insulation detection circuit formed by the insulation detection circuit and the load.

[0143] When the insulation fault location method in this application is used in a vehicle, it can employ strategies such as active discharge function, passive discharge function, reverse pre-charge function, and voltage stabilization function to achieve insulation detection function when power is off.

[0144] In one embodiment of this application, as shown in FIG10, the load may include a motor and a three-phase inverter, and the insulation fault location method includes:

[0145] S104 controls the closing of the upper or lower bridge arm switch of any phase bridge arm in the three-phase inverter corresponding to the motor, so that the insulation detection circuit and the motor form a fourth insulation detection circuit, and the motor insulation abnormality is located based on the fourth insulation detection circuit.

[0146] In some embodiments, the first and second switching circuits are disconnected, the third switching circuit is closed, and the upper or lower bridge arm switch of any phase arm in the three-phase inverter is closed, forming a fourth insulation detection circuit with the motor. The bus capacitor in the fourth insulation detection circuit is directly connected to the motor.

[0147] When the upper arm switch is closed, the insulation resistance Rp2 of the load's positive bus to the vehicle ground is connected in parallel with the motor's insulation resistance Rm. When the lower arm switch is closed, the insulation resistance Rn2 of the load's negative bus to the vehicle ground is connected in parallel with the motor's insulation resistance Rm. Therefore, the insulation detection circuit in the fourth insulation detection circuit detects the insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative terminals to the vehicle ground. Thus, the motor's insulation resistance value Rm can be calculated based on the insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative terminals to the vehicle ground, and the insulation resistance values ​​Rp2 and Rn2 of the load's positive / negative bus to the vehicle ground.

[0148] In one embodiment of this application, the motor insulation anomaly location is based on the fourth insulation detection circuit, including: calculating the motor insulation resistance value Rm based on the insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative poles to the vehicle body ground detected by the insulation detection circuit in the fourth insulation detection circuit;

[0149] If the motor insulation resistance Rm is less than the third preset threshold, then the motor insulation is determined to be abnormal.

[0150] In some embodiments, the insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative terminals to the vehicle body ground, detected by the insulation detection circuit in the fourth insulation detection circuit, are stored. The motor insulation resistance value Rm can be calculated based on the insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative terminals to the vehicle body ground, and the insulation resistance values ​​Rp2 and Rn2' of the load's positive / negative busbars to the vehicle body ground.

[0151] If the motor insulation resistance Rm is less than a third preset threshold, the motor insulation is determined to be abnormal. Otherwise, the motor insulation is determined to be normal.

[0152] In one embodiment of this application, the insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative terminals to the vehicle ground are detected by the insulation detection circuit in the fourth insulation detection circuit, which may include:

[0153] In response to the closing of the upper bridge arm switch of any phase in the three-phase inverter corresponding to the control motor, the insulation resistance value Rm of the motor is calculated based on the insulation resistance value Rp2 and the insulation resistance value Rp2'.

[0154] In response to the closing of any phase lower arm switch in the three-phase inverter corresponding to the control motor, the insulation resistance value Rm of the motor is calculated based on the insulation resistance value Rn2 and the insulation resistance value Rn2'.

[0155] In some embodiments, when the upper bridge arm switch is closed, the motor insulation resistance Rm can be calculated using the formula Rm=Rp2*Rp2' / (Rp2-Rp2') based on the insulation resistance values ​​Rp2 and Rp2'. When the lower bridge arm switch is closed, the motor insulation resistance Rm can be calculated using the formula Rm=Rn2*Rn2' / (Rn2-Rn2') based on the insulation resistance values ​​Rn2 and Rn2'.

[0156] In one embodiment of this application, when the insulation fault location device is provided with a first switching circuit connected between the insulation detection circuit and the battery pack, and a second switching circuit connected between the battery pack and the load, but not a third switching circuit connected between the insulation detection circuit and the load, when the first switching circuit and the second switching circuit are turned on, the upper or lower bridge arm switch of any phase bridge arm in the three-phase inverter can also be closed to perform insulation detection and location of the motor.

[0157] Specifically, when the upper arm switch is closed, the insulation resistance Rp2 of the load's positive bus to the vehicle ground is connected in parallel with the motor's insulation resistance Rm. When the lower arm switch is closed, the insulation resistance Rn2 of the load's negative bus to the vehicle ground is connected in parallel with the motor's insulation resistance Rm. At this time, the insulation detection circuit detects the insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative terminals to the vehicle ground. Therefore, the motor's insulation resistance value Rm can be calculated based on the insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative terminals to the vehicle ground, as well as the insulation resistance values ​​Rp1' and Rn1' of the vehicle's DC high voltage terminals to the vehicle ground.

[0158] In some embodiments, when the upper bridge arm switch is closed, the motor insulation resistance Rm can be calculated using the formula Rm=Rp1'*Rp2' / (Rp1'-Rp2') based on the insulation resistance values ​​Rp1' and Rp2'. When the lower bridge arm switch is closed, the motor insulation resistance Rm can be calculated using the insulation resistance values ​​Rn1' and Rn2', and the formula Rm=Rn1'*Rn2' / (Rn1'-Rn2').

[0159] In one embodiment of this application, given the insulation resistance values ​​Rp1' and Rn1' of the vehicle's DC high voltage positive / negative terminals to the vehicle ground, and the insulation resistance values ​​Rp2 and Rn2 of the load's positive / negative busbars to the vehicle ground, the insulation resistance values ​​Rp1 and Rn1 of the battery pack's positive / negative terminals to the vehicle ground are calculated based on the insulation resistance values ​​Rp1', Rn1', Rp2, and Rn2.

[0160] In some embodiments, the battery insulation resistance Rp1 can be calculated using the formula Rp1=Rp2*Rp1' / (Rp2-Rp1') based on the insulation resistance values ​​Rp2 and Rp1'. Similarly, the battery insulation resistance Rn1 can be calculated using the formula Rn1=Rn2*Rn1' / (Rn2-Rn1') based on the insulation resistance values ​​Rn2 and Rn1'.

[0161] The following is a detailed description of the insulation detection and positioning method of this application, using the method in the embodiments of this application to perform insulation detection and positioning of a vehicle as an example:

[0162] As shown in Figure 11, the vehicle control system enters a vehicle leakage current condition, disconnecting the third switch K3 and the fourth switch K4, and closing the first switch K3 and the second switch K4 to perform battery insulation anomaly detection. The insulation resistance values ​​Rp1 and Rn1 of the battery pack's positive / negative terminals to the vehicle ground, detected by the insulation detection circuit, are saved. It is then determined whether the insulation resistance value Rp1 or Rn1 is less than a first preset threshold. If the insulation resistance value Rp1 or Rn1 is less than the first preset threshold, a battery pack insulation fault is located, and further investigation of battery problems is conducted. Otherwise, the battery pack insulation is determined to be normal.

[0163] In addition to locating insulation faults in the battery pack, insulation fault detection can also be performed on the load and motor.

[0164] In some embodiments, the first switch K3 and the second switch K4 are disconnected, and the fifth switch K5 and the sixth switch K6 are closed. The insulation detection circuit can be powered using any of the following strategies: active discharge function, passive discharge function, reverse pre-charge function, and voltage regulation function. The insulation resistance values ​​Rp2 and Rn2 of the positive / negative busbars of the load to the vehicle ground, detected by the insulation detection circuit, are saved. If either the insulation resistance value Rp2 or Rn2 is less than a second preset threshold, a DC insulation fault in the high-voltage load is determined, and the high-voltage load and busbar faults are investigated. Otherwise, the DC insulation of the high-voltage load is determined to be normal. The upper or lower bridge arm switch of the three-phase inverter corresponding to the target motor is closed. The insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative terminals to the vehicle ground are saved. The insulation resistance value Rm of the target motor is calculated based on the insulation resistance values ​​Rp2' and Rn2'. If the insulation resistance value Rm of the target motor is less than a third preset threshold, an insulation fault in the target motor is determined, and the insulation problem of the target motor is investigated. If the insulation resistance Rm of the target motor is greater than or equal to the third preset threshold, then the insulation of the target motor is determined to be normal. The above steps can be used to check multiple motors in the vehicle, such as the electric compressor, drive motor, and generator.

[0165] In this system, while checking that the battery pack insulation is normal, insulation fault detection can also be performed on the load and motor. In some embodiments, the third switch K3 and the fourth switch K4 are closed to perform insulation detection on the load. The insulation resistance values ​​Rp1' and Rn1' of the vehicle's DC high voltage positive / negative terminals to the vehicle ground, obtained by the insulation detection circuit at this time, are saved. The insulation resistance values ​​Rp2 and Rn2 of the load's positive / negative busbars to the vehicle ground are calculated based on the insulation resistance values ​​Rp1' and Rn1'. If the insulation resistance value Rp2 or Rn2 is less than a second preset threshold, a DC insulation fault in the high voltage load is determined, and the high voltage load and busbar faults are investigated. Otherwise, the DC insulation of the high voltage load is determined to be normal. The upper or lower bridge arm switch of the three-phase inverter corresponding to the target motor is closed. The insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative terminals to the vehicle ground are saved at this time. The insulation resistance value Rm of the target motor is calculated based on the insulation resistance values ​​Rp2' and Rn2'. If the insulation resistance Rm of the target motor is less than the third preset threshold, an insulation fault in the target motor is determined, and the insulation problem of the target motor is investigated. If the insulation resistance Rm of the target motor is greater than or equal to the third preset threshold, the insulation of the target motor is determined to be normal. The above steps can be used to check multiple motors in the vehicle, such as the electric compressor, drive motor, and alternator, one by one.

[0166] If the battery, high-voltage load DC, and motor insulation are all normal, the problem can be identified as another fault, such as a false alarm.

[0167] The insulation fault location method in this application embodiment controls the on / off state of the first switch circuit, the second switch circuit, and the third switch circuit, so that the insulation detection circuit forms corresponding insulation detection circuits with the battery pack, the load, and the motor, respectively, thereby realizing insulation detection and location of the battery pack, the load, and the motor. It has the advantages of being simpler and more flexible in implementation.

[0168] This application provides a computer-readable storage medium.

[0169] In this embodiment, computer instructions are stored on a computer-readable storage medium. When the computer instructions are executed by a processor, the insulation fault location method described above is implemented.

[0170] This application provides a controller.

[0171] In this embodiment, the controller may include a memory and a processor. The memory stores computer instructions, and when the computer instructions are executed by the processor, the insulation fault location method described above is implemented.

[0172] Figure 12 is a structural block diagram of the controller according to an embodiment of this application.

[0173] As shown in Figure 12, the controller 500 includes a processor 501 and a memory 503. The processor 501 and the memory 503 are connected, for example, via a bus 502. The controller 500 may also include a transceiver 504. It should be noted that in practical applications, the transceiver 504 is not limited to one unit, and the structure of the controller 500 does not constitute a limitation on the embodiments of this application.

[0174] Processor 501 may be a CPU (Central Processing Unit), a general-purpose processor, a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this application. Processor 501 may also be a combination that implements computational functions, such as including one or more microprocessor combinations, a combination of a DSP and a microprocessor, etc.

[0175] Bus 502 may include a pathway for transmitting information between the aforementioned components. Bus 502 may be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus, etc. Bus 502 may be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in Figure 12, but this does not mean that there is only one bus or one type of bus.

[0176] The memory 503 stores computer instructions corresponding to the insulation fault location method of the above embodiments of this application. These computer instructions are controlled and executed by the processor 501. The processor 501 executes the computer instructions stored in the memory 503 to implement the content shown in the aforementioned method embodiments.

[0177] The controller 500 includes, but is not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Android Devices), PMPs (Portable Media Players), and in-vehicle terminals (e.g., in-vehicle navigation terminals), as well as fixed terminals such as digital TVs (Digital Television) and desktop computers. The controller 500 shown in Figure 12 is merely an example and should not be construed as limiting the functionality and scope of the embodiments in this application.

[0178] The computer-readable storage medium and controller in this application embodiment utilize the above-mentioned insulation fault location method to control the conduction of the first switching circuit and the on / off state of the second and third switching circuits, so that the insulation detection circuit forms corresponding insulation detection loops with the battery pack, load and motor respectively, thereby realizing insulation detection and location of the battery pack, load and motor. It has the advantages of simpler and more flexible implementation.

[0179] This application provides an insulation fault location system.

[0180] Figure 13 is a structural block diagram of an insulation fault location system according to an embodiment of this application. As shown in Figure 13, the insulation fault location system 1000 may include the insulation fault location device 100 as described above.

[0181] Figure 14 is a structural block diagram of an insulation fault location system according to an embodiment of this application. As shown in Figure 14, the insulation fault location system 1000 may include the controller 500 as described above.

[0182] This application provides a vehicle.

[0183] Figure 15 is a schematic diagram of a vehicle according to an embodiment of this application. As shown in Figure 15, the vehicle 2000 may include the insulation fault location system 1000 as described above.

[0184] In some embodiments, a main positive contactor and a main negative contactor are provided between the vehicle's battery pack and the load. When the insulation fault location system 1000 is implemented on the vehicle, the main positive contactor can be used as a third switch K3 and the main negative contactor can be used as a fourth switch K4.

[0185] The insulation fault location device 100 of this application embodiment is mainly based on electric vehicle design and does not require additional cost.

[0186] The vehicle in this application embodiment, based on the above-mentioned insulation fault location system 1000, has a simpler and more flexible implementation method, and can be associated with big data. It can quickly locate and handle after-sales vehicle leakage problems through big data, saving personnel on the cost of going out for inspection.

[0187] The vehicle in this application embodiment can employ strategies such as active discharge function, passive discharge function, reverse pre-charge function, and voltage stabilization function to achieve insulation detection function when the vehicle is powered off.

[0188] The vehicle described in this application embodiment can perform insulation testing at both ends of the battery and the high-voltage load.

[0189] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples of computer-readable media (a non-exhaustive list) include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), fiber optic devices, and compact disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which the program can be printed, as the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0190] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0191] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0192] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0193] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0194] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0195] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0196] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. An insulation fault location device, wherein, The device includes: Insulation detection circuit; A first switching circuit, connected to the insulation detection circuit and used to connect to the battery pack, is configured to form a first insulation detection loop with the insulation detection circuit and the battery pack; and The second switching circuit, used to connect the battery pack and the load respectively, is configured to make the load and the battery pack form a load power circuit.

2. The insulation fault location device according to claim 1, wherein, The second switching circuit is also configured as follows: Together with the first switching circuit, the insulation detection circuit and the load form a second insulation detection circuit.

3. The insulation fault location device according to any one of claims 1-2, wherein, The first switching circuit includes: A first switch, wherein a first terminal of the first switch is connected to a first terminal of the insulation detection circuit, and a second terminal of the first switch is connected to the positive terminal of the battery pack; and The second switch has its first end connected to the second end of the insulation detection circuit and its second end connected to the negative terminal of the battery pack.

4. The insulation fault location device according to any one of claims 1-3, wherein, The second switching circuit includes: A third switch, wherein the first terminal of the third switch is connected to the positive terminal of the battery pack, and the second terminal of the third switch is connected to the input terminal of the load; and The fourth switch has its first end connected to the negative terminal of the battery pack and its second end connected to the output terminal of the load.

5. The insulation fault location device according to any one of claims 1-4, wherein, The device further includes: A third switching circuit is connected to the insulation detection circuit and used to connect the load, and together with the first switching circuit and the second switching circuit, is configured to form a third insulation detection loop between the insulation detection circuit and the load.

6. The insulation fault location device according to claim 5, wherein, The third switching circuit includes: A fifth switch, wherein the first terminal of the fifth switch is connected to the first terminal of the insulation detection circuit, and the second terminal of the fifth switch is connected to the input terminal of the load; and The sixth switch has its first end connected to the second end of the insulation detection circuit, and its second end connected to the output end of the load.

7. The insulation fault location device according to claim 5 or 6, wherein, The device further includes: The bus capacitor, which is connected to the battery pack and the load respectively, is configured to provide a detection voltage to the insulation detection circuit and the load to form a third insulation detection loop.

8. The insulation fault location device according to claim 7, wherein, The device further includes an auxiliary power supply connected to the bus capacitor and configured to supply power to the bus capacitor.

9. The insulation fault location device according to claim 8, wherein, The auxiliary power supply includes a battery and a DC-DC converter, and the battery is connected to the bus capacitor through the DC-DC converter.

10. The insulation fault location device according to claim 8 or 9, wherein, The auxiliary power supply includes an AC-DC inverter and a generator. The generator is connected to the bus capacitor through the AC-DC inverter, and the generator uses an engine to generate electricity.

11. The insulation fault location device according to any one of claims 7-10, wherein, The load includes a motor and a three-phase inverter. The DC terminal of the three-phase inverter is connected to the bus capacitor, and the AC terminal of the three-phase inverter is connected to the motor. The upper and lower bridge arm switches of any phase arm of the three-phase inverter are configured to form a fourth insulation detection circuit with the motor.

12. The insulation fault location device according to claim 11, wherein, The motor includes at least one of the following: an electric compressor, a drive motor, and a generator.

13. The insulation fault location device according to any one of claims 1-12, wherein, The insulation detection circuit adopts the unbalanced bridge method for insulation detection.

14. The insulation fault location device according to claim 13, wherein, The insulation detection circuit includes a first resistor, a second resistor, a third resistor, a sampling resistor, and a seventh switch. The first end of the first resistor is connected to the first end of the insulation detection circuit. The second end of the first resistor is connected to the first end of the second resistor to form a first node. The first node is connected to the first end of the seventh switch. The second end of the seventh switch is connected to the second end of the insulation detection circuit. The second end of the second resistor is connected to the first end of the third resistor to form a second node. The second node is grounded. The second end of the third resistor is connected to the first end of the sampling resistor. The first end of the sampling resistor is connected to a voltage sampling module. The second end of the sampling resistor is connected to the second end of the insulation detection circuit.

15. An insulation fault location method, wherein, An insulation fault location device is used, the insulation fault location device including an insulation detection circuit, a first switching circuit and a second switching circuit, the first switching circuit being used to connect the insulation detection circuit and a battery pack, and the second switching circuit being used to connect the battery pack and a load, the method including: The first switching circuit is turned on, so that the insulation detection circuit and the battery pack form a first insulation detection loop, and the battery insulation anomaly is located based on the first insulation detection loop.

16. The insulation fault location method according to claim 15, wherein, The method includes: The second switching circuit is turned on, so that the insulation detection circuit and the load form a second insulation detection loop, and the load insulation anomaly is located based on the second insulation detection loop.

17. The insulation fault location method according to claim 15 or 16, wherein, The method of locating battery insulation anomalies based on the first insulation detection circuit includes: If either the insulation resistance value Rp1 or the insulation resistance value Rn1 of the positive / negative terminal of the battery pack to the vehicle ground, detected by the insulation detection circuit in the first insulation detection circuit, is less than a first preset threshold, then the insulation of the battery pack is determined to be abnormal.

18. The insulation fault location method according to claim 16, wherein, The load insulation anomaly location based on the second insulation detection circuit includes: Based on the insulation resistance values ​​Rp1' and Rn1' of the positive / negative DC high voltage poles of the vehicle to the vehicle body ground detected by the insulation detection circuit in the second insulation detection circuit, as well as the insulation resistance values ​​Rp1 and Rn1, the insulation resistance values ​​Rp2 and Rn2 of the positive / negative busbars of the load to the vehicle body ground are calculated. If either the insulation resistance value Rp2 or the insulation resistance value Rn2 is less than a second preset threshold, then the load insulation is determined to be abnormal.

19. The insulation fault location method according to any one of claims 15-18, wherein, The insulation fault location device includes a third switching circuit, which is used to connect the insulation detection circuit and the load. The method further includes: The first and second switching circuits are turned off, and the third switching circuit is turned on, so that the insulation detection circuit and the load form a third insulation detection loop, and the load insulation anomaly is located based on the third insulation detection loop.

20. The insulation fault location method according to claim 19, wherein, The load insulation anomaly location based on the third insulation detection circuit includes: If either the insulation resistance value Rp2 or the insulation resistance value Rn2 of the positive / negative busbar of the load to the vehicle ground, detected by the insulation detection circuit in the third insulation detection circuit, is less than a second preset threshold, then the load insulation is determined to be abnormal.

21. The insulation fault location method according to claim 19 or 20, wherein, The insulation fault location device includes bus capacitors connected to the battery pack and the load respectively, and the method further includes: When the second switching circuit is turned off, the bus capacitor provides a detection voltage to the insulation detection circuit and the load to form a third insulation detection circuit.

22. The insulation fault location method according to claim 21, wherein, The insulation fault location device includes an auxiliary power supply connected to the bus capacitor, and the method further includes: Control the auxiliary power supply to supply power to the bus capacitor.

23. The insulation fault location method according to any one of claims 20-22, wherein, The load includes a motor and a three-phase inverter, and the method includes: The upper or lower bridge arm switch of any phase bridge arm in the three-phase inverter corresponding to the motor is closed, so that the insulation detection and the motor form a fourth insulation detection circuit, and the motor insulation abnormality is located based on the fourth insulation detection circuit.

24. The insulation fault location method according to claim 23, wherein, The method of locating motor insulation anomalies based on the fourth insulation detection circuit includes: Based on the insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative terminals to the vehicle body ground detected by the insulation detection circuit in the fourth insulation detection circuit, the insulation resistance value Rm of the motor is calculated. If the motor insulation resistance Rm is less than a third preset threshold, then the motor insulation is determined to be abnormal.

25. The insulation fault location method according to claim 24, wherein, The step of detecting the insulation resistance values ​​Rp2' and Rn2' of the vehicle's positive / negative terminals to the vehicle ground according to the insulation detection circuit in the fourth insulation detection circuit includes: In response to the closing of the upper bridge arm switch of any phase in the three-phase inverter corresponding to the control motor, the insulation resistance value Rm of the motor is calculated based on the insulation resistance value Rp2 and the insulation resistance value Rp2'. In response to the closing of any phase lower arm switch in the three-phase inverter corresponding to the control motor, the insulation resistance value Rm of the motor is calculated based on the insulation resistance value Rn2 and the insulation resistance value Rn2'.

26. A computer-readable storage medium having stored thereon computer instructions, wherein, When the computer instructions are executed by the processor, the insulation fault location method as described in any one of claims 15-25 is implemented.

27. A controller, comprising a memory and a processor, wherein the memory stores computer instructions, wherein... When the computer instructions are executed by the processor, the insulation fault location method as described in any one of claims 15-25 is implemented.

28. An insulation fault location system, wherein, Includes the insulation fault location device as described in any one of claims 1-14, or the controller as described in claim 27.

29. A vehicle, wherein, Including the insulation fault location system as described in claim 28.

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