Earth leakage protection system and vehicle

Abstract

A ground fault protection system and a vehicle, the system including: a first Y capacitor and a second Y capacitor connected in series; a power battery, the positive terminal of the power battery being connected to first ends of the first Y capacitor and the second Y capacitor connected in series, and second ends of the first Y capacitor and the second Y capacitor being connected to a negative terminal of the power battery and a negative terminal of a DC charging port, respectively; and a controller configured to control an energy leakage loop to avoid electric shock when acquired ground fault-related parameters satisfy preset ground fault protection conditions.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This disclosure claims priority to and the benefit of Chinese Patent Application No. 202211716536.4, entitled "ELECTRIC LEAKAGE PROTECTION SYSTEM AND VEHICLE," filed on December 29, 2022. The entire contents of the above disclosure are incorporated herein by reference.

[0002] The present disclosure relates to the field of vehicle technology, and more particularly to ground fault protection systems and vehicles. [Background technology]

[0003] With the rapid development of electric vehicles, users' requirements for vehicle charging performance are gradually increasing. Currently, the common charging modes for electric vehicles include AC charging and DC charging.

[0004] If a vehicle experiences a ground fault and a user simultaneously touches the DC charging port and the vehicle body ground, a large amount of electricity stored in the vehicle's capacitor will be discharged through the user's body, putting the user at risk of electric shock and creating a safety hazard. Summary of the Invention

[0005] The present disclosure provides a ground fault protection system and a vehicle for solving the above technical problems.

[0006] A first aspect of an embodiment of the present disclosure is a ground fault protection system, comprising: A DC charging port, a charge port capacitor, a first end of the charge port capacitor being connected to a positive pole of the DC charge port and a second end of the charge port capacitor being connected to a negative pole of the DC charge port; a first Y capacitor and a second Y capacitor, the first Y capacitor being connected in series with the second Y capacitor, and a connection midpoint between the first Y capacitor and the second Y capacitor being connected to a vehicle body ground; a power battery, the positive terminal of which is connected to first ends of a first Y capacitor and a second Y capacitor connected in series, and the second ends of which are connected to a negative terminal of the power battery and a negative terminal of a DC charging port, respectively; a controller configured to control an energy leakage circuit to avoid electric shock when the acquired leakage-related parameters satisfy a preset leakage protection condition, the energy leakage circuit being formed by a second Y capacitor, a vehicle body earth, an external conductive member, a DC charging port, and a charging port capacitor; The present invention provides a ground fault protection system including:

[0007] A second aspect of the embodiment of the present disclosure provides a vehicle including the ground fault protection system provided in the first aspect of the embodiment of the present disclosure.

[0008] According to the above technical solution, when the acquired leakage-related parameters satisfy a preset leakage protection condition, the controller can determine that a large amount of electricity is stored in the first Y capacitor or the second Y capacitor. In this case, when a user touches the DC charging port, the large amount of electricity stored in the first Y capacitor or the second Y capacitor will be discharged through the user's body, resulting in electric shock. To prevent the user from being electric shock, the energy leakage circuit can be controlled to prevent the user from being electric shock.

[0009] Other features and advantages of the present disclosure are described in detail in the detailed description section below.

[0010] The accompanying drawings are intended to provide a further understanding of the present disclosure and to constitute a part of this specification, and the following accompanying drawings and specific implementations are used to explain the disclosure and not to constitute a limitation thereof. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram of a ground fault protection system according to an exemplary embodiment; [Figure 2] 1 is a schematic diagram of a leakage current detection principle according to an exemplary embodiment; [Figure 3] FIG. 2 is a logic schematic diagram of a vehicle in a parking operation state according to an exemplary embodiment. [Figure 4] FIG. 2 is a logic schematic diagram of a vehicle during boost voltage DC charging operation in accordance with an exemplary embodiment. [Figure 5] FIG. 2 is a logic schematic diagram of a vehicle in a reduced voltage DC discharge operating state according to an exemplary embodiment. [Figure 6] FIG. 1 is a block diagram of a vehicle in accordance with an exemplary embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Specific implementations of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific implementations described herein are merely used to describe and explain the present disclosure, and are not intended to limit the present disclosure.

[0013] It should be noted that in this disclosure, all actions to obtain signals, information or data are performed in accordance with the applicable data protection regulations and policies of the country in which they are located and with the authorization of the owner of the corresponding device.

[0014] The present disclosure provides a leakage current protection system. Referring to Figure 1, the leakage current protection system includes a DC charging port, a charging port capacitor C3, a first end of which is connected to the positive electrode of the DC charging port and a second end of which is connected to the negative electrode of the DC charging port, a charging port capacitor C3, a first Y capacitor C1 and a second Y capacitor C2, the first Y capacitor C1 being connected in series to the second Y capacitor C2, and a connection midpoint between the first Y capacitor C1 and the second Y capacitor C2 being connected to the vehicle body ground VSS, and a power battery VCC, the positive electrode of which is connected in series to the first Y capacitor C1 and the second Y capacitor C2. a power battery VCC, the first ends of which are connected to a negative electrode of the power battery VCC and a negative electrode of the DC charging port, and the second ends of the series-connected first Y capacitor C1 and second Y capacitor C2 are connected to a negative electrode of the power battery VCC and a negative electrode of the DC charging port, respectively; and a controller, the controller being configured to control an energy leakage circuit to avoid electric shock when the acquired leakage-related parameters satisfy a preset leakage-current protection condition, the energy leakage circuit being formed by the second Y capacitor C2, the vehicle body ground VSS, the external conductive member R4, the DC charging port, and the charging port capacitor C3.

[0015] For example, referring to FIG. 1, the first end of the charging port capacitor C3 is connected to the positive pole of the DC charging port, and the second end of the charging port capacitor C3 is connected to the negative pole of the DC charging port. In the process of a vehicle performing boost voltage DC charging, the charging pile charges the power battery through the charging port. However, the voltage required by the power battery is different from the voltage provided by the charging pile. In this case, the vehicle can notify the charging pile of the required charging voltage, and the charging pile converts the charging voltage to the voltage required by the vehicle and charges the charging port capacitor C3 with a large amount of electricity. Then, the charging port capacitor C3 charges the power battery VCC with a large amount of electricity that matches the power battery VCC. The positive terminal of the power battery VCC is connected to the first end of the first Y-capacitor C1, the negative terminal of the power battery VCC is connected to the negative terminal of the DC charging port, the second end of the second Y-capacitor C2 is connected to the junction between the negative terminal of the power battery VCC and the negative terminal of the DC charging port, and the second end of the first Y-capacitor C1 is connected to the first end of the first Y-capacitor C1. Vehicle body ground VSS is connected to the junction between the second end of the first Y-capacitor C1 and the first end of the second Y-capacitor C2. Vehicle body ground VSS may be understood as the conductive housing of the vehicle, such as the vehicle housing or the floor within the vehicle. One end of the external conductive member R4 is connected to the positive terminal of the DC charging port, and the other end of the external conductive member R4 is connected to the positive terminal of the power battery VCC using an analog leakage resistance, which may be an analog human body resistance.

[0016] Because a user typically comes into contact with the vehicle body ground VSS, the vehicle's overall insulation resistances, such as the positive earth insulation resistance R1 and the negative earth insulation resistance R2, may be used to prevent large currents emitted by components such as the power battery VCC and high-voltage components from being discharged to the human body through the vehicle body ground VSS. It can be understood that both the positive earth insulation resistance R1 and the negative earth insulation resistance R2 are insulation resistances between the vehicle's components, such as the power battery VCC and high-voltage components, simulated by the ground fault protection system according to the present disclosure and the vehicle body ground VSS, and are used to isolate the components, such as the power battery VCC and high-voltage components, from the vehicle body ground VSS to prevent large currents emitted by the components, such as the power battery VCC and high-voltage components, from being transmitted to the vehicle body ground VSS. In fact, the vehicle's overall insulation resistance, which isolates the power battery VCC from the vehicle body ground VSS, does not only include the positive earth insulation resistance R1 and the negative earth insulation resistance R2.

[0017] This disclosure provides an analog leakage energy circuit for an analog leakage scenario, as shown in Figures 2 and 3. One end of the positive contact K1 is connected to one end of the analog leakage switch K3, and the other end of the positive contact K1 is connected to the positive pole of the power battery VCC. One end of the negative contact K2 is connected to the negative pole of VCC, and the other end of the negative contact K2 is connected to the external conductive member R4. When the positive contact K1 and the negative contact K2 are closed, the power battery VCC is conducted to the DC charging port.

[0018] When the analog earth leakage switch K3 is not closed, the positive earth insulation resistor R1 and the negative earth insulation resistor R2 bisect the voltage of the power battery VCC. For example, if the power battery VCC generates a voltage of 500V, the positive earth insulation resistor R1 and the negative earth insulation resistor R2 each generate 250V. When the analog earth leakage switch K3 is closed, the analog earth leakage resistor R3 simulates a ground leakage scenario for the power battery VCC. Because the resistance value of the analog earth leakage resistor R3 is small, the positive terminal of the power battery VCC is directly connected to one end of the negative earth insulation resistor R2, and the negative terminal of the power battery VCC is connected to one end of the negative earth insulation resistor R2. As a result, the voltage across the negative earth insulation resistor R2 rises to 500V. In this case, the voltage difference between the first voltage and the second voltage varies from 0 to 500V and is greater than the preset voltage threshold. When the second voltage rises to 500 V, the amount of electricity stored in the second Y capacitor C2 connected across the negative earth insulation resistance R2 also increases suddenly.

[0019] In this case, if the user simultaneously touches the positive terminal of the DC charging port (in FIG. 1, the positive terminal is above the DC charging port and the negative terminal is below the DC charging port) and the vehicle ground VSS, the energy leakage circuit will be conductive, as indicated by the arrow in FIG. 1. In this case, a large amount of electricity in the second Y capacitor C2 will be discharged through the external conductive member R4 of the energy leakage circuit, i.e., the large amount of electricity stored in the second Y capacitor C2 will be discharged through the human body, putting the user at risk of electric shock and creating a potential safety hazard. The analog human body resistor R4 is a resistor used to simulate the human body.

[0020] In order to provide electric leakage protection for users in the event of electric leakage of the entire vehicle and ensure the safety of users, the present disclosure proposes to control the energy leakage circuit to prevent electric shock to users when the acquired electric leakage-related parameters meet the preset conditions.

[0021] 2 and 3, the leakage-related parameters include a first voltage U1 of the first Y-capacitor C1 and a second voltage U2 of the second Y-capacitor C2, and the preset leakage-protection condition is that the voltage difference between the first voltage and the second voltage is greater than a preset voltage threshold. The first voltage is the voltage across the positive ground insulation resistor R1, and the second voltage is the voltage across the negative ground insulation resistor R2. The preset voltage threshold may be 0 or another value. This is not a limitation of the present disclosure.

[0022] For example, when the voltage difference between the first voltage and the second voltage is greater than a preset voltage threshold, this indicates that a large amount of electricity has been stored in the second Y capacitor C2 or the first Y capacitor C1. In this case, when a user touches the DC charging port, a large amount of electricity stored in the second Y capacitor C2 or the first Y capacitor C1 will be discharged through the human body, putting the user at risk of electric shock. To prevent the user from being at risk of electric shock, the energy leakage circuit may be controlled to prevent the user from being electric shock when the voltage difference between the first voltage and the second voltage is greater than the preset voltage threshold.

[0023] The earth leakage related parameters include a positive earth resistance value and a negative earth resistance value, and the preset earth leakage protection condition is that the positive earth resistance value is different from the negative earth resistance value.

[0024] For example, if the positive earth resistance value of the positive earth insulation resistor R1 differs from the negative earth resistance value of the negative earth insulation resistor R2, the voltage difference between the first voltage and the second voltage also changes, for example, from the initial 0 to a value greater than a preset voltage threshold. In this case, a large amount of electricity is stored in the first Y capacitor C1 or the second Y capacitor C2. When a user touches the DC charging port, the large amount of electricity stored in the first Y capacitor C1 or the second Y capacitor C2 is discharged through the human body, putting the user at risk of electric shock. To prevent the user from being at risk of electric shock, the energy leakage circuit may be controlled to prevent the user from being electric shock when the positive earth resistance value differs from the negative earth resistance value.

[0025] According to the above technical solution, when the acquired leakage-related parameters satisfy the preset leakage protection conditions, the controller can determine that a large amount of electricity is stored in the first Y capacitor C1 or the second Y capacitor C2. In this case, when a user touches the DC charging port, the large amount of electricity stored in the first Y capacitor C1 or the second Y capacitor C2 will be discharged through the user's body, resulting in electric shock. To prevent the user from being electric shock, the energy leakage circuit can be controlled to prevent the user from being electric shock.

[0026] In a possible implementation, the controller can control the energy leakage circuit in the following two ways to prevent the user from getting an electric shock.

[0027] Method 1: When the acquired leakage-related parameters meet the preset leakage protection conditions, the energy leakage circuit is cut off to avoid electric shock.

[0028] Specifically, when the acquired leakage-related parameters meet the preset leakage protection conditions, the charging port cover is closed, and the connection between the external conductive member R4 and the DC charging port is cut off, thereby breaking the energy leakage circuit.

[0029] When the vehicle has a function to close the charging port cover, if the acquired leakage-related parameters meet the preset leakage protection conditions, the charging port cover will be closed to prevent the external conductive member R4 from contacting the DC charging port, thereby cutting off the connection between the external conductive member R4 and the DC charging port and further cutting off the energy leakage circuit, i.e., the energy leakage circuit will not be conductive.

[0030] For example, if the acquired leakage-related parameters meet the preset leakage protection conditions, the DC charging port is determined to be at risk of leakage. In this case, the charging port cover can be closed to prevent the DC charging port from being exposed to the external environment, ensuring that the human body cannot come into contact with the DC charging port, thereby avoiding the risk of electric shock.

[0031] Method 2: When the acquired leakage-related parameters meet the preset leakage protection conditions, the energy output by the energy leakage circuit is controlled to be smaller than the preset energy threshold to avoid electric shock.

[0032] Specifically, when the acquired leakage-related parameters satisfy the preset leakage protection conditions, the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2 is cut off, and the energy in the first Y capacitor C1 and the second Y capacitor C2 is released, making the energy output by the energy leakage circuit to the DC charging port less than the preset energy threshold.

[0033] For example, if the acquired leakage-related parameters satisfy a preset leakage protection condition, it is determined that the DC charging port is at risk of leakage. In this case, the connection between the positive contact K1 and / or the negative contact K2 can be cut off to disconnect the power battery VCC from the first Y capacitor C1 and the second Y capacitor C2, preventing the power battery VCC from continuously leaking current into the DC charging port. In addition, the electronic control unit 1 in FIG. 1 can be controlled to discharge most of the energy generated by the first Y capacitor C1 or the second Y capacitor C2 to the motor 2 to consume the large amount of electricity discharged by the second Y capacitor C2, thereby significantly reducing the energy discharged from the second Y capacitor C2 to the DC charging port. This ensures that there is no risk of electric shock even if a human body comes into contact with the DC charging port.

[0034] It may be understood that the preset energy threshold is a protection threshold. If the preset energy threshold is less than the preset energy threshold, there is no risk of electric shock when a user touches the DC charging port. If the preset energy threshold is greater than or equal to the preset energy threshold, the user may be at risk of electric shock.

[0035] According to the above technical solution, the controller controls the charging port cover to close, preventing the DC charging port from being exposed to the external environment and preventing contact between the external conductive member R4 and the DC charging port, thereby preventing electric shock to the external conductive member R4. The controller further controls the power battery VCC to disconnect the electrical connection between the first Y-capacitor C1 and the second Y-capacitor C2, preventing the power battery VCC from continuously leaking large amounts of electricity to the second Y-capacitor C2. The motor 2 can be used to consume the large amount of electricity generated by the second Y-capacitor C2. Therefore, the energy transferred to the DC charging port is less than the preset energy threshold, and there is no risk of electric shock even if the external conductive member R4 comes into contact with the DC charging port.

[0036] In a possible implementation, when the vehicle is in a target operating state such as step-up voltage DC charging, step-down voltage DC discharging, driving operating state, or parking operating state, the external conductive member R4 may come into contact with the DC charging port, resulting in electric shock to the external conductive member R4. Therefore, to prevent electric shock to the external conductive member R4, the present disclosure further includes the following examples.

[0037] The target operating state may be an operating state in which a user may come into contact with the DC charging port.

[0038] The ground fault protection system further includes a motor 2, the motor 2 including multi-phase windings (e.g., a three-phase winding as shown in FIG. 1 ), first ends of the multi-phase windings connected to each other and leading out an N-wire, the N-wire being connected to a first end of a charging port capacitor C3. The ground fault protection system further includes an electronic control unit 1, the electronic control unit 1 including multi-phase bridge arms, the midpoints of the bridge arms connected to corresponding windings, first ends of the multi-phase bridge arms connected to each other to form a first bus terminal, the first bus terminal being connected to the positive pole of a power battery VCC, second ends of the multi-phase bridge arms connected to each other to form a second bus terminal, the second bus terminal being connected to the negative pole of the power battery VCC. A controller is connected to the multi-phase bridge arms.

[0039] 1, the midpoint of each phase bridge arm is the connection point between the emitter of the upper NPN triode and the collector of the lower NPN triode in each group of NPN triodes, the first end (first bus terminal) of the multi-phase bridge arm is the end to which the collectors of the multiple upper NPN triodes in the electronic control unit 1 are connected, and the second end (second bus terminal) of the multi-phase bridge arm is the end to which the emitters of the multiple lower NPN triodes in the electronic control unit 1 are connected. The first bus terminal is connected to the positive pole of the power battery VCC via a positive contact K1, and the second bus terminal is connected to the negative pole of the power battery VCC via a negative contact K2.

[0040] In some embodiments, the controller is configured to control at least one phase bridge arm of the multi-phase bridge arms to perform boosted voltage DC charging. Referring to Figure 4, during the boosted voltage DC charging process, when the acquired leakage-related parameters satisfy a preset leakage protection condition, the boosted voltage DC charging is stopped, the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2 is cut off, and the energy of the first Y capacitor C1 and the second Y capacitor C2 is released to make the energy output by the energy leakage circuit smaller than a preset energy threshold.

[0041] When the charging connector uses a DC charging port to perform boost voltage DC charging of the power battery VCC, the DC charging port is exposed to the external environment, and an operator may come into contact with the DC charging port when pulling out or inserting the charging connector into the DC charging port. In this case, if the acquired leakage-related parameters meet the preset leakage-protection conditions, this indicates a high risk of electric shock to the operator. To prevent electric shock to the operator, the following actions may be taken:

[0042] (1) Stopping the boost voltage DC charging of the power battery VCC; (2) Disconnecting the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2; (3) Discharging the energy of the first Y capacitor C1 and the second Y capacitor C2 to reduce the energy output to the DC charging port by the energy leakage circuit to less than a preset energy threshold.

[0043] During the process of boosting the voltage of the power battery VCC using the DC charging port, if the power battery VCC experiences a risk of electrical leakage, a large amount of electricity surrounding the power battery VCC may be directly loaded onto the second Y capacitor C2, causing a sudden increase in the amount of electricity in the second Y capacitor C2. Similarly, the amount of electricity in the first Y capacitor C1 may also suddenly increase. In this case, when a user touches the DC charging port, the energy in the first Y capacitor C1 or the second Y capacitor C2 will be released into the human body through an energy leakage circuit. Therefore, by performing the above operation (1), the electronic control unit 1 can prevent the current output by the motor 2 from continuously leaking to the power battery VCC, and the power battery VCC can be prevented from continuously leaking direct current to the second Y capacitor C2, so that the amount of electricity output by the second Y capacitor C2 can be gradually reduced; by performing the above operation (2), the energy output by the power battery VCC can also be prevented from being input to the second Y capacitor C2; and by performing the above operation (3), the energy output by the second Y capacitor C2 to the DC charging port is reduced to below a preset energy threshold, so that there is no risk of electric shock even if a user touches the DC charging port.

[0044] In the process of boosting voltage AC charging of the power battery VCC at the AC charging port, the controller can further control the DC charging port cover to be closed to prevent users from touching the DC charging port when the power battery VCC is leaking, and the second Y capacitor C2 and the first Y capacitor C1 release energy into the DC charging port.

[0045] In some embodiments, the controller is further configured to control at least one phase bridge arm of the multi-phase bridge arms to perform step-down DC discharge. Referring to Figure 5, during the step-down DC discharge process, when the acquired leakage-related parameters satisfy a preset leakage protection condition, the step-down DC discharge is stopped, the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2 is cut off, and the energy of the first Y capacitor C1 and the second Y capacitor C2 is released.

[0046] The step-down DC discharge operating state includes the whole-vehicle external discharge operating state or the intelligent charging operating state. The whole-vehicle external discharge operating state refers to the operating state in which the power battery VCC supplies power to an external electrical device of the vehicle, such as an external induction cooking device. The intelligent charging function refers to the operating state in which the power battery VCC charges a low-voltage battery, such as charging a 12V low-voltage battery with 500V high-voltage electricity.

[0047] When the power battery VCC uses a DC charging port for step-down DC discharge, the DC charging port is used as the vehicle's discharge port and is exposed to the external environment. A user may come into contact with the DC charging port when unplugging or inserting an electrical appliance into the DC charging port. In this case, if the acquired leakage-related parameters meet the preset leakage protection conditions, this indicates a high risk of electric shock to the user. To prevent electric shock to the operator, the following actions may be taken:

[0048] (4) stopping external discharge of the power battery VCC; (5) disconnecting the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2; and (6) discharging the energy of the first Y capacitor C1 and the second Y capacitor C2 to reduce the energy output to the DC charging port by the energy leakage circuit to less than a preset energy threshold.

[0049] During the step-down DC discharge of the power battery VCC, if the power battery VCC experiences a risk of electrical leakage, a large amount of electricity surrounding the power battery VCC may be directly loaded onto the second Y capacitor C2, causing a sudden increase in the amount of electricity in the second Y capacitor C2. Similarly, the amount of electricity in the first Y capacitor C1 may also suddenly increase. In this case, when a user touches the DC charging port, the energy in the first Y capacitor C1 or the second Y capacitor C2 will be released into the human body through the energy leakage circuit. Therefore, by performing the above operation (4), the power battery VCC may be prevented from continuously leaking DC to the second Y capacitor C2, and therefore the amount of electricity output by the second Y capacitor C2 may be gradually reduced; by performing the above operation (5), the energy output by the power battery VCC may also be prevented from being input to the second Y capacitor C2; and by performing the above operation (6), the energy output by the second Y capacitor C2 to the DC charging port is made smaller than a preset energy threshold, so that there is no risk of electric shock even if a user touches the DC charging port.

[0050] During the process of discharging the power battery VCC through the AC charging port, the controller can also directly control the DC charging port cover to close, so as to avoid the risk of electric shock when the user touches the DC charging port.

[0051] In some embodiments, the controller is further configured to close the charge port cover when the vehicle is in driving operation.

[0052] When the vehicle is in a driving operating state, the vehicle does not supply power to the outside through the DC charging port, and the vehicle does not obtain external power through the DC charging port. Therefore, to avoid the risk of electric shock to the user, when the vehicle is in a driving operating state, the charging port cover may be directly controlled to be closed, and thus the external conductive member R4 and the DC charging port remain disconnected.

[0053] Specifically, when the vehicle is in a driving state, the charging port cover is closed when the acquired leakage-related parameters satisfy the preset leakage-protection conditions.

[0054] When the vehicle is in a driving state, for example, when the vehicle is traveling at a low speed, if the acquired leakage-related parameters meet the preset protection conditions, which indicates a risk of electric shock after a user touches the DC charging port, the charging port cover of the DC charging port is controlled to close, thereby preventing the risk of electric shock caused by the user touching the DC charging port.

[0055] In some embodiments, the controller is configured to disconnect the electrical connection between the power battery VCC and the first Y-capacitor C1 and the second Y-capacitor C2 and release energy from the first Y-capacitor C1 and the second Y-capacitor C2 when the vehicle is in a parking operating state and the acquired leakage-current-related parameters satisfy a preset leakage-current protection condition.

[0056] Referring to FIG. 3, when the vehicle is in a power-up operating state, the vehicle is in a target gear, the vehicle speed is less than a preset vehicle speed, and the charging port is in an open state, the vehicle is determined to be in a parking operating state; alternatively, when the vehicle is in a power-up driving operating state, the vehicle is in a target gear, and the vehicle speed is less than a preset vehicle speed, the vehicle is determined to be in a parking operating state.

[0057] The target gear includes a parking gear or a neutral gear. When the vehicle is in the parking gear or the neutral gear, this indicates that the vehicle can stop moving, and only in this case can the user contact the charging port; when the vehicle is in the non-parking gear or the neutral gear, this indicates that the vehicle is moving, and in this case, the user cannot contact the charging port of the moving vehicle.

[0058] When the vehicle is in parking gear or neutral gear, the vehicle speed may be low, and it may be understood that the vehicle is coasting, for example. The vehicle speed may be determined to further determine whether the vehicle has stopped running or is coasting. When the vehicle speed is lower than a preset vehicle speed (e.g., 5 km / h), this indicates that the vehicle has stopped running, and the user may contact the vehicle's DC charging port. In this case, if the acquired leakage-related parameters satisfy the preset leakage protection conditions, the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2 may be disconnected, and the energy in the first Y capacitor C1 and the second Y capacitor C2 may be discharged. When the vehicle speed is greater than or equal to the preset vehicle speed, this indicates that the vehicle is coasting. In this case, the user cannot contact the DC charging port of a vehicle that is coasting. Therefore, the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2 does not need to be cut off, and the energy in the first Y capacitor C1 and the second Y capacitor C2 does not need to be discharged.

[0059] It may be understood that in a parking operation state, the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2 may be disconnected and the energy of the first Y capacitor C1 and the second Y capacitor C2 may be discharged only when the vehicle is in the target gear and the vehicle speed is less than a preset vehicle speed, and that the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2 cannot be disconnected and the energy of the first Y capacitor C1 and the second Y capacitor C2 cannot be discharged simply when the vehicle speed is less than the preset vehicle speed.

[0060] The reason is that when the vehicle starts in a forward gear (non-target gear), there is a stage when the vehicle speed becomes slower than the preset vehicle speed after the vehicle starts moving. In this case, if the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2 is directly cut off when the vehicle speed is slower than the preset vehicle speed, the vehicle cannot start smoothly.

[0061] Therefore, if the power battery VCC is leaking, when the vehicle is in a target gear such as a parking gear or a neutral gear, the vehicle speed is less than the preset vehicle speed, the vehicle is parked, and the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2 may be disconnected, and the energy of the first Y capacitor C1 and the second Y capacitor C2 may be released to ensure the normal running of the vehicle.

[0062] In any implementation of the present disclosure, if a vehicle has a charge port cover detection function, the charge port cover detection function may be enabled to detect a charge port cover when the acquired leakage-related parameters satisfy a preset leakage protection condition, the vehicle is in a target gear, and the vehicle speed is less than a preset vehicle speed. When the charge port cover is in an open state, the electrical connection between the power battery VCC and the first Y-capacitor C1 and the second Y-capacitor C2 is disconnected, and the energy in the first Y-capacitor C1 and the second Y-capacitor C2 is discharged. When the charge port cover is in a closed state, the electrical connection between the power battery VCC and the first Y-capacitor C1 and the second Y-capacitor C2 does not need to be disconnected, and the energy in the first Y-capacitor C1 and the second Y-capacitor C2 does not need to be discharged, and the charge port cover remains closed.

[0063] When the vehicle does not have a charging port cover detection function, the charging port cover does not need to be detected.When the acquired leakage-related parameters meet the preset leakage protection conditions, the vehicle is in the target gear, and the vehicle speed is lower than the preset vehicle speed, the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2 is directly disconnected, and the energy in the first Y capacitor C1 and the second Y capacitor C2 is discharged.

[0064] Certainly, the vehicle can further output a warning signal when the acquired leakage-related parameters meet the preset leakage protection conditions to instruct the user that the vehicle is at risk of leakage.

[0065] In any embodiment of the present disclosure, if the acquired leakage-current-related parameters do not satisfy the preset leakage-current protection conditions, the leakage-current-related parameters continue to be monitored, and the energy leakage circuit is controlled to avoid electric shock only when the leakage-current-related parameters satisfy the preset leakage-current-protection conditions.

[0066] According to the above technical solution, when the vehicle is in a target operating state, such as a driving operating state, a parking operating state, a step-up voltage DC charging operating state, or a step-down voltage DC discharging operating state, if it is detected that the leakage-related parameters satisfy the preset leakage protection condition, this indicates that there is a risk of electric shock after a user touches the DC charging port. In this case, the charging port cover may be controlled to be closed, and / or the electrical connection between the power battery VCC and the first Y capacitor C1 and the second Y capacitor C2 may be controlled to be disconnected, and the energy of the first Y capacitor C1 and the second Y capacitor C2 may be discharged to prevent the user from getting an electric shock.

[0067] 6 is a block diagram of a vehicle 600 according to an exemplary embodiment. For example, vehicle 600 may be a hybrid vehicle, or a non-hybrid vehicle, an electric vehicle, a fuel cell vehicle, or another type of vehicle. Vehicle 600 may be an autonomous vehicle, a semi-autonomous vehicle, or a non-autonomous vehicle.

[0068] 6, vehicle 600 may include various subsystems, such as an information and entertainment system 610, a sensing system 620, a decision and control system 630, a drive system 640, and a computing platform 650. Vehicle 600 may further include more or fewer subsystems, and each subsystem may include multiple components. Additionally, each subsystem and component of vehicle 600 may be interconnected via wires or wirelessly.

[0069] In some embodiments, the information and entertainment system 610 may include a communication system, an entertainment system, a navigation system, and the like.

[0070] The sensing system 620 may include several sensors configured to sense ambient environmental information of the vehicle 600. For example, the sensing system 620 may include a global positioning system (the global positioning system may be a GPS system, a BeiDou system, or another positioning system), an inertial measurement unit (IMU), a laser radar, a millimeter wave radar, an ultrasonic radar, and a camera device.

[0071] The decision control system 630 may include a computing system, an overall vehicle control unit, a steering system, an accelerator, and a braking system.

[0072] Drive system 640 may include components that provide power for vehicle 600 to move. In an embodiment, drive system 640 may include an engine, an energy source, a drive system, and wheels. The engine may be one or more combinations of an internal combustion engine, an electric motor, and an air compression engine. The engine may convert energy provided by an energy source into mechanical energy.

[0073] Some or all of the functions of vehicle 600 are controlled by computing platform 650. Computing platform 650 may include at least one processor 651 and memory 652. Processor 651 may execute instructions 653 stored in memory 652.

[0074] The processor 651 may be any conventional processor, such as a commercially available CPU, etc. The processor may further include, for example, a graphics processing unit (GPU), a field programmable gate array (FPGA), a system on a chip (SOC), an application specific integrated circuit (ASIC), or a combination thereof.

[0075] The memory 652 may be implemented by any type of volatile or non-volatile storage device, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk, or optical disk, or a combination thereof.

[0076] In addition to instructions 653, memory 652 may further store data such as road maps, route information, location, direction, speed, and other vehicle data. The data stored in memory 652 may be used by computing platform 650.

[0077] In this embodiment of the present disclosure, the processor 651 can execute instructions 653 to complete all or part of the steps of the above-mentioned earth leakage protection system. Preferred implementation forms of the present disclosure have been described in detail above with reference to the accompanying drawings. However, the present disclosure is not limited to the specific details of the above-mentioned implementation forms. Within the technical concept of the present disclosure, multiple simple modifications may be made to the technical solution of the present disclosure, and these simple modifications fall within the protection scope of the present disclosure.

[0078] It is further noted that the specific technical features described in the above specific embodiments may be combined in any suitable manner where not inconsistent, and various possible combinations are not specifically described in the present disclosure to avoid unnecessary repetition.

[0079] In addition, different implementations of the present disclosure may be combined in any manner without departing from the spirit of the present disclosure, and these combinations are also considered to be disclosed in the present disclosure.

Claims

1. 1. A ground fault protection system comprising: A DC charging port, a charge port capacitor, a first end of the charge port capacitor connected to a positive terminal of the DC charge port and a second end of the charge port capacitor connected to a negative terminal of the DC charge port; a first Y capacitor and a second Y capacitor, the first Y capacitor being connected in series with the second Y capacitor, and a connection midpoint between the first Y capacitor and the second Y capacitor being connected to a vehicle body ground; a power battery, wherein a positive terminal of the power battery is connected to a first end of the first Y capacitor and the second Y capacitor connected in series, and second ends of the first Y capacitor and the second Y capacitor connected in series are connected to a negative terminal of the power battery and the negative terminal of the DC charging port, respectively; a controller configured to control an energy leakage circuit to avoid electric shock when the acquired earth leakage-related parameter satisfies a preset earth leakage protection condition, the energy leakage circuit being formed by the second Y capacitor, the vehicle body earth, the external conductive member, the DC charging port, and the charging port capacitor; A ground fault protection system comprising:

2. the leakage-related parameters include a first voltage of the first Y-capacitor and a second voltage of the second Y-capacitor; The ground fault protection system of claim 1 , wherein the preset ground fault protection condition is that a voltage difference between the first voltage and the second voltage is greater than a preset voltage threshold.

3. the leakage current-related parameters include a positive earth resistance value and a negative earth resistance value; 3. The earth leakage protection system according to claim 1, wherein the preset earth leakage protection condition is that the positive earth resistance value is different from the negative earth resistance value.

4. The earth leakage protection system according to any one of claims 1 to 3, wherein the controller is configured to disconnect the energy leakage circuit to avoid electric shock when the acquired earth leakage-related parameters satisfy the preset earth leakage protection conditions.

5. 5. The ground fault protection system according to claim 1, wherein the controller is configured to close a charging port cover and disconnect the external conductive member from the DC charging port to disconnect the energy leakage circuit when the acquired ground fault-related parameter satisfies the preset ground fault protection condition.

6. The earth leakage protection system according to any one of claims 1 to 5, wherein the controller is configured to control the energy output by the energy leakage circuit to be less than a preset energy threshold when the acquired earth leakage-related parameter satisfies the preset earth leakage protection condition, thereby avoiding electric shock.

7. 7. The earth leakage protection system according to claim 1, wherein the controller is configured, when the acquired earth leakage-related parameter satisfies the preset earth leakage protection condition, to disconnect the electrical connection between the power battery and the first Y-capacitor and the second Y-capacitor, and release energy from the first Y-capacitor and the second Y-capacitor, so that the energy output by the energy leakage circuit is less than a preset energy threshold.

8. a motor (2), the motor (2) including multi-phase windings, first ends of the multi-phase windings connected together and leading out N wires, the N wires connected to the first end of the charge port capacitor; an electronic control unit (1), the electronic control unit (1) comprising multi-phase bridge arms, the midpoint of each phase bridge arm being connected to a corresponding winding, first ends of the multi-phase bridge arms being connected to each other to form a first bus terminal, the first bus terminal being connected to the positive pole of the power battery, and second ends of the multi-phase bridge arms being connected to each other to form a second bus terminal, the second bus terminal being connected to the negative pole of the power battery; and Furthermore, 8. The earth leakage protection system according to claim 1, wherein the controller is connected to the multi-phase bridge arms, and the controller is configured to control at least one phase bridge arm of the multi-phase bridge arms to perform boosted voltage DC charging.

9. 9. The earth leakage protection system according to claim 1, wherein, during a process of boosted voltage DC charging, when the acquired earth leakage-related parameter satisfies the preset earth leakage protection condition, the controller is further configured to stop the boosted voltage DC charging, cut off electrical connections between the power battery and the first Y capacitor and the second Y capacitor, and release energy in the first Y capacitor and the second Y capacitor so as to make the energy output by the energy leakage circuit smaller than a preset energy threshold.

10. The ground fault protection system of any one of claims 1 to 9, wherein the controller is further configured to close a charge port cover when the vehicle is in driving operation.

11. The ground-fault protection system of claim 8 , wherein the controller is further configured to control at least one phase bridge arm of the multi-phase bridge arms to perform a step-down voltage DC discharge.

12. 12. The earth leakage protection system according to claim 1, wherein the controller is further configured to, when the acquired earth leakage-related parameter satisfies the preset earth leakage protection condition during a process of step-down voltage DC discharge, stop the step-down voltage DC discharge, disconnect the power battery from the first Y capacitor and the second Y capacitor, and release energy from the first Y capacitor and the second Y capacitor.

13. 13. The earth leakage protection system according to claim 1, wherein the controller is configured to, when the vehicle is in a parking operation state and the acquired earth leakage-related parameters satisfy the preset earth leakage protection condition, disconnect the electrical connection between the power battery and the first Y-capacitor and the second Y-capacitor, and release energy from the first Y-capacitor and the second Y-capacitor.

14. A vehicle comprising the earth leakage protection system according to any one of claims 1 to 13.

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