Equipotential diagnosis system and vehicle

Abstract

The utility model provides an equipotential diagnosis system and a vehicle, belongs to the technical field of vehicles, and is applied to a power supply system of the vehicle, the power supply system comprises a high-voltage power battery and a plurality of high-voltage loads connected with the high-voltage power battery, and the system comprises a detection circuit, a power supply circuit and a control circuit, the conductive shell is also in equipotential connection with a vehicle body of the vehicle; the control circuit is connected in series in a connecting line of the high-voltage power battery and the high-voltage load, and the input end of the control circuit is connected with the output end of the detection circuit; the detection circuit is configured to be switched on in response to a power-on signal of the vehicle; and the control circuit is configured to cut off the connection between the high-voltage power battery and the plurality of high-voltage loads under the condition that the output voltage of the detection circuit is higher than the null-drift voltage. According to the equipotential diagnosis system provided by the embodiment of the invention, when equipotential detection fails, the high-voltage power battery is disconnected in time, and electric shock is avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of vehicles, and in particular relates to an equipotential diagnosis system and a vehicle. Background Art

[0002] The high-voltage load shell and body of new energy vehicles use equipotential connection technology to reduce the voltage to avoid the risk of electric shock. If the equipotential connection fails, users can easily accidentally touch the conductive shell or body of the high-voltage load on the car and cause serious electric shock accidents. Utility Model Content

[0003] In view of the above problems, embodiments of the present application provide an equipotential diagnostic system and a vehicle to overcome the above problems or at least partially solve the above problems.

[0004] In a first aspect of an embodiment of the present application, an equipotential diagnostic system is provided, which is applied to a power supply system of a vehicle. The power supply system includes a high-voltage power battery E1 and a plurality of high-voltage loads connected to the high-voltage power battery E1. The system includes:

[0005] A detection circuit 1 is located on at least one of the high-voltage loads and is connected between a power supply and a conductive housing 3 of the high-voltage load, the conductive housing also being connected to the body of the vehicle at an equipotential level;

[0006] A control circuit 2 is connected in series to the connection line between the high-voltage power battery E1 and the high-voltage load, and the input end of the control circuit 2 is connected to the output end of the detection circuit 1;

[0007] The detection circuit 1 is configured to be turned on in response to a power-on signal of the vehicle;

[0008] The control circuit 2 is configured to cut off the connection between the high-voltage power battery E1 and the plurality of high-voltage loads when the output voltage of the detection circuit 1 is higher than the zero-drift voltage;

[0009] The zero-drift voltage is a voltage indicating that the equipotential connection is normal.

[0010] Furthermore, the detection circuit 1 includes: a first switch unit 4 and a sampling resistor R; the first switch unit 4 is connected in series between the power supply and the first end of the sampling resistor R, and the second end of the sampling resistor R is connected to the conductive housing 3 of the high-voltage load; wherein,

[0011] The first switch unit 4 is configured to be turned on in response to the power-on signal, so that the power supply outputs a supply voltage to the first end of the sampling resistor R;

[0012] The control circuit 2 is configured to cut off the connection between the high-voltage power battery E1 and the plurality of high-voltage loads when the output voltage at the second end of the sampling resistor R is higher than the zero-drift voltage.

[0013] Furthermore, the detection circuit 1 further includes: a control unit 5, which is connected in parallel between the input end of the first switch unit 4 and the second end of the sampling resistor R, and is connected to the control circuit 2; wherein,

[0014] The control unit 5 is configured to output a disconnection signal to the control circuit 2 when the absolute value of the difference between the output voltage and the supply voltage is less than a preset difference;

[0015] The control circuit 2 is further configured to cut off the connection between the high-voltage power battery E1 and the plurality of high-voltage loads in response to the disconnection signal.

[0016] Furthermore, the power supply is a low-voltage DC power supply E2, which is connected to the detection circuit 1 and the control circuit 2, respectively, and serves as the power supply for the detection circuit 1 and the control circuit 2; the system further includes:

[0017] The fuse box 6 is connected in series to the power supply line between the low-voltage DC power supply E2 and the detection circuit 1, and the power supply line between the low-voltage DC power supply E2 and the control circuit 2;

[0018] The fuse box 6 is configured to cut off the power supply line when the power supply voltage output by the low-voltage DC power supply E2 to the detection circuit 1 and / or the control circuit 2 exceeds a preset voltage.

[0019] Furthermore, the control circuit 2 includes: a second switch unit 7 and a third switch unit 8, the second switch unit 7 is connected in series to the first power supply circuit between the power supply and the third switch unit 8, and the third switch unit 8 is also connected in series to the second power supply circuit between the high-voltage power battery E1 and the plurality of high-voltage loads;

[0020] Wherein, the second switch unit 7 is configured to be disconnected when the output voltage of the detection circuit 1 is higher than the zero-drift voltage, so as to cut off the first power supply circuit;

[0021] The third switch unit 8 is configured to disconnect the second power supply circuit when the first power supply circuit is disconnected; and is configured to connect the second power supply circuit when the first power supply circuit is connected.

[0022] Furthermore, the third switch unit 8 includes a first relay K1 and a second relay K2; wherein,

[0023] The first relay K1 is connected between the positive electrode of the high-voltage power battery E1 and the plurality of high-voltage loads; the second relay K2 is connected between the negative electrode of the high-voltage power battery E1 and the plurality of high-voltage loads;

[0024] The control end of the first relay K1 and the control end of the second relay K2 are both connected to the output end of the second switch unit 7;

[0025] The second switch unit 7 further includes an input end and a control end. The input end of the second switch unit 7 is connected to the power supply, and the control end of the second switch unit 7 is connected to the output end of the detection circuit 1 .

[0026] Furthermore, the second switch unit 7 includes a first transistor Q1 and a second transistor Q2, wherein:

[0027] The collector of the first transistor Q1 and the collector of the second transistor Q2 are respectively connected to the power supply, and the base of the first transistor Q1 and the base of the second transistor Q2 are respectively connected to the output end of the detection circuit 1;

[0028] The emitter of the first transistor Q1 is connected to the control end of the first relay K1, and the emitter of the second transistor Q2 is connected to the control end of the second relay K2;

[0029] The first transistor Q1 is configured to control the first relay K1 to disconnect from the positive electrode of the high-voltage power battery E1 when the output voltage of the detection circuit 1 is higher than the zero-drift voltage;

[0030] The second transistor Q2 is configured to control the second relay K2 to disconnect from the negative electrode of the high-voltage power battery E1 when the output voltage of the detection circuit 1 is higher than the zero-drift voltage.

[0031] Furthermore, the second switch unit 7 further includes a third transistor Q3; the third switch unit 8 further includes a pre-charge relay K3 and a pre-charge resistor R0, wherein,

[0032] The collector of the third transistor Q3 is connected to the power supply, the base of the third transistor Q3 is connected to the output end of the detection circuit 1, and the emitter of the third transistor Q3 is connected to the control end of the pre-charge relay K3;

[0033] The pre-charging relay K3 is connected between the plurality of high-voltage loads and the first end of the pre-charging resistor R0, and the second end of the pre-charging resistor R0 is connected to the positive electrode of the high-voltage power battery E1;

[0034] The second transistor Q2 is further configured to close when the output voltage of the detection circuit 1 is lower than or equal to the zero-drift voltage and the first relay K1 is not closed, thereby controlling the second relay K2 to be closed;

[0035] The third transistor Q3 is configured to close when the second relay K2 is closed and the first relay K1 is not closed, thereby controlling the pre-charge relay K3 to be closed;

[0036] The pre-charging resistor R0 is configured to stabilize the voltage output by the high-voltage power battery E1 in response to the engagement of the second relay K2 and the pre-charging relay K3.

[0037] Furthermore, the detection circuit 1 is provided in the high-voltage power battery E1 , wherein the detection circuit 1 is respectively connected to the conductive housing of the high-voltage power battery E1 , the power supply, and the second switch unit 7 .

[0038] According to a second aspect of an embodiment of the present application, a vehicle is provided, wherein the vehicle includes the equipotential diagnostic system according to the first aspect of an embodiment of the present application.

[0039] An equipotential diagnostic system provided by this embodiment is applied to a vehicle's power supply system, which includes a high-voltage power battery E1 and multiple high-voltage loads connected to the high-voltage power battery E1. The system includes: a detection circuit 1, located on at least one of the high-voltage loads, and connected between a power supply source and a conductive shell 3 of the high-voltage load, the conductive shell also being connected to the vehicle body at the same potential; a control circuit 2, connected in series in the connection line between the high-voltage power battery E1 and the high-voltage load, the input end of the control circuit 2 being connected to the output end of the detection circuit 1; the detection circuit 1 is configured to be turned on in response to a power-on signal of the vehicle; the control circuit 2 is configured to cut off the connection between the high-voltage power battery E1 and the multiple high-voltage loads when the output voltage of the detection circuit 1 is higher than the zero-drift voltage; wherein the zero-drift voltage is a voltage that indicates that the equipotential connection is normal.

[0040] Therefore, through the equipotential diagnostic system of this embodiment, through the connection relationship between the high-voltage power battery E1, the high-voltage load, the detection circuit 1 and the control circuit 2, after the vehicle is powered on, the detection circuit 1 can be controlled to be turned on. Then, the detection circuit 1 monitors the connection status between the high-voltage power battery E1 and the high-voltage load. When the detection circuit 1 detects that the output voltage is higher than the zero-drift voltage, it indicates that there may be a problem with the equipotential connection. At this time, the control circuit 2 will cut off the connection between the high-voltage power battery E1 and the multiple high-voltage loads to avoid the failure of the equipotential connection to cut off the connection between the high-voltage power battery E1 and the multiple high-voltage loads in time, resulting in the high voltage output of the high-voltage power battery E1 to the high-voltage load being output to the conductive shell of the high-voltage load or the body of the vehicle, increasing the risk of accidental electric shock to users near the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0042] Figure 1 This is a module schematic diagram of an equipotential diagnostic system provided in an embodiment of the present application;

[0043] Figure 2 It is aimed at Figure 1 A schematic diagram of the module details of an equipotential diagnostic system is provided;

[0044] Figure 3 It is aimed at Figure 2 Detailed schematic diagram of the module of the control circuit;

[0045] Figure 4 This is a schematic diagram of the circuit structure of an equipotential diagnostic system provided in an embodiment of the present application;

[0046] Reference numerals:

[0047] Detection circuit; 2-control circuit; 3-conductive housing of high-voltage load; 4-first switch unit; 5-control unit; 6-fuse box; 7-second switch unit; 8-third switch unit; R-sampling resistor; R0-pre-charge resistor; Q1-first transistor; Q2-second transistor; Q3-third transistor; K1-first relay; K2-second relay; K3-pre-charge relay; E1-high-voltage power battery; E2-low-voltage DC power supply. DETAILED DESCRIPTION

[0048] The exemplary embodiments of the present application will be described in more detail below in conjunction with the accompanying drawings in the embodiments of the present application. Although the accompanying drawings show exemplary embodiments of the present application, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0049] In related technologies, in order to address the risk of electric shock, high-voltage insulation testing is performed on vehicles. The vehicle's high-voltage insulation testing solution often uses an unbalanced bridge insulation monitoring solution, and its diagnosis time is affected by the system capacitance and takes a long time. During the long confirmation time, the high-voltage system may cause current leakage to the vehicle body or other conductive components, which will bring a greater risk of electric shock to users.

[0050] Furthermore, if a vehicle's high-voltage insulation fails and equipotential bonding occurs simultaneously, the high-voltage system is normally completely insulated from the vehicle body. However, if the high-voltage insulation fails, the high-voltage system could leak current to the vehicle body or other conductive components, increasing the possibility of electric shock. Equipotential bonding is designed to prevent electric shock by preventing current flow when a person touches a metal part of the vehicle, even in the event of an insulation failure. If the equipotential bonding fails simultaneously, the risk of electric shock is significantly increased.

[0051] In view of this, this embodiment provides an equipotential diagnostic system and a vehicle, which are connected between the power supply and the conductive casing of the high-voltage load through a detection circuit. After the vehicle is powered on, the detection circuit monitors the connection status between the high-voltage power battery and the high-voltage load. When the detection circuit detects that the output voltage is higher than the zero-drift voltage, the control circuit can promptly cut off the connection between the high-voltage power battery and multiple high-voltage loads to prevent the user from being electric shocked.

[0052] Reference Figure 1 , Figure 1 This is a schematic diagram of a module of an equipotential diagnostic system provided in an embodiment of the present application, which is applied to the power supply system of a vehicle. Figure 1 As can be seen from the figure, the power supply system includes a high-voltage power battery E1 and multiple high-voltage loads connected to the high-voltage power battery E1. The system includes: a detection circuit 1 and a control circuit 2. The connection relationship between the detection circuit 1, the control circuit 2, the high-voltage power battery E1 and the high-voltage loads is:

[0053] The detection circuit 1 is located on at least one high-voltage load and is connected between the power supply and the conductive housing 3 of the high-voltage load, and the conductive housing is also connected to the body of the vehicle at the same potential;

[0054] The control circuit 2 is connected in series to the connection line between the high-voltage power battery E1 and the high-voltage load, and the input end of the control circuit 2 is connected to the output end of the detection circuit 1;

[0055] The detection circuit 1 and the control circuit 2 are each configured to have the following functions:

[0056] a detection circuit 1, configured to be turned on in response to a power-on signal of the vehicle;

[0057] The control circuit 2 is configured to cut off the connection between the high-voltage power battery E1 and multiple high-voltage loads when the output voltage of the detection circuit 1 is higher than the zero-drift voltage; wherein the zero-drift voltage is a voltage indicating that the equipotential connection is normal.

[0058] In this embodiment, combined with Figure 1 The detection circuit 1 is a circuit used to detect whether the conductive casing 3 of the high-voltage load is well connected to the vehicle body at the same potential. Since the detection circuit 1 is located on the high-voltage load, it is connected between the power supply and the conductive casing 3 of the high-voltage load, and the conductive casing 3 of the high-voltage load is connected to the vehicle body at the same potential. If the equipotential connection is good, the power supply voltage output by the power supply will flow into the ground through the conductive casing and the vehicle body. If the equipotential connection is poor or the equipotential connection is disconnected, the power supply voltage output by the power supply will not completely flow into the ground through the conductive casing and the vehicle body, and may be connected to other conductive casings or components on the vehicle that are not equipotentially connected, thereby causing leakage.

[0059] In addition, the power supply is not the high-voltage power battery E1, but can be other power supplies on the vehicle that can provide low-voltage power supply. Therefore, whether the high-voltage power battery E1 supplies power to the high-voltage load or not, it will not affect the diagnosis of the equipotential connection of the high-voltage load. Therefore, the detection circuit 1 can be turned on in response to the power-on signal of the vehicle. The signal can be a low-voltage power-on signal or a wake-up signal of the vehicle. Then the power supply can supply power to the conductive shell 3 of the high-voltage load through the detection circuit 1, and then the detection circuit 1 can detect the power supply voltage output by the power supply and the voltage output to the conductive shell through the detection circuit 1, that is, the output of the detection circuit 1. If the equipotential connection is good and the zero-drift voltage is not considered, the output voltage of detection circuit 1 is 0V. The zero-drift voltage refers to the voltage between the high-voltage power battery E1 and the high-voltage load when the power supply system is operating normally and there are no abnormalities. It can also be understood as the voltage of a normal equipotential connection. If the zero-drift voltage is considered, if the equipotential connection is good, the output voltage of detection circuit 1 is between 0V and the zero-drift voltage. Therefore, when the output voltage of detection circuit 1 is less than or equal to the zero-drift voltage, it indicates that the equipotential connection is normal. If the output voltage of detection circuit 1 is greater than the zero-drift voltage, it indicates that the equipotential connection is abnormal. Control circuit 2 is a switching circuit that can be used to disconnect the high-voltage power battery E1 from the high-voltage load. It cooperates with detection circuit 1. Therefore, when the output voltage of detection circuit 1 exceeds the zero-drift voltage, to prevent the user from electric shock, control circuit 2 will disconnect the high-voltage power battery E1 from the multiple high-voltage loads, preventing the high voltage output by high-voltage power battery E1 from discharging through the high-voltage loads.

[0060] To sum up, through the equipotential diagnostic system provided by this embodiment, as long as the vehicle is in the power-on state, the high-voltage loads in the vehicle can be diagnosed with equipotential diagnosis. When it is diagnosed that the equipotential connection is abnormal, the connection between the high-voltage power battery E1 and multiple high-voltage loads can be cut off in time through the control circuit 2. In this way, it can be avoided that in the related technology, high-voltage insulation monitoring can only be performed when the high voltage is powered on, which results in too long detection time and inability to cut off the connection between the high-voltage power battery E1 and multiple high-voltage loads in time, thereby avoiding the high voltage output of the high-voltage power battery E1 from leaking through the high-voltage load and endangering the safety of the user.

[0061] In a specific embodiment, referring to Figure 2 , Figure 2 It is aimed at Figure 1 A detailed schematic diagram of the module of the equipotential diagnostic system is provided. Figure 2As can be seen, the detection circuit 1 includes: a first switch unit 4 and a sampling resistor R; the first switch unit 4 is connected in series between the power supply and the first end of the sampling resistor R, and the second end of the sampling resistor R is connected to the conductive housing 3 of the high-voltage load; wherein the first switch unit 4 is configured to be turned on in response to a power-on signal so that the power supply outputs a supply voltage to the first end of the sampling resistor R; the control circuit 2 is configured to cut off the connection between the high-voltage power battery E1 and the multiple high-voltage loads when the output voltage at the second end of the sampling resistor R is higher than the zero-drift voltage.

[0062] In this embodiment, the sampling resistor R is a relatively large resistance value. When the equipotential connection is normal, the power supply voltage output by the power supply is divided by the sampling resistor R, and the normal output voltage will be less than or equal to the zero drift voltage. The first switch unit 4 can be a transistor or a MOS tube. Figure 2 According to the connection relationship between the first switch unit 4 and the sampling resistor R, and the function configured by the first switch unit 4, in this embodiment, the first switch unit 4 can be turned on when a power-on signal arrives, and then a power supply voltage is output to the first end of the sampling resistor R through the power supply source, the power supply voltage is divided by the sampling resistor R, and the output voltage through the second end of the sampling resistor R after the voltage division is compared with the zero-drift voltage. When the output voltage is higher than the zero-drift voltage, the control circuit 2 cuts off the connection between the high-voltage power battery E1 and the multiple loads.

[0063] In a specific embodiment, referring to Figure 2 The detection circuit 1 also includes: a control unit 5, which is connected in parallel between the input end of the first switch unit 4 and the second end of the sampling resistor R, and is connected to the control circuit 2; wherein the control unit 5 is configured to output a disconnection signal to the control circuit 2 when the absolute value of the difference between the output voltage and the supply voltage is less than a preset difference; the control circuit 2 is further configured to cut off the connection between the high-voltage power battery E1 and the multiple high-voltage loads in response to the disconnection signal.

[0064] In this embodiment, the control unit 5 is a circuit for comparing the output voltage of the sampling resistor R with the supply voltage and making a corresponding response according to the comparison result. The circuit can determine whether the equipotential connection is disconnected.

[0065] When the equipotential connection is disconnected, the detection circuit 1 is not grounded and is in an open circuit state. The resistance of resistor R is much smaller than the open circuit resistance. At this time, the output voltage is not much different from the supply voltage. A preset difference is set. The preset difference can be slightly greater than 0, such as 0.2V, 0.4V, 0.6V, etc. When the absolute value of the difference between the output voltage and the supply voltage is less than the preset difference, it indicates that the equipotential connection is abnormal. A disconnect signal can be output to the control circuit 2 to disconnect the high-voltage power battery E1 from the multiple high-voltage loads, thereby preventing the high voltage output by the high-voltage power battery E1 from leaking through the high-voltage loads and endangering the safety of the user.

[0066] Combine Figure 2 According to the connection relationship of the control unit 5 in the detection circuit 1 and the function configured by the control unit 5, when the absolute value of the difference between the output voltage and the supply voltage is less than the preset difference, it is determined that the equipotential connection of the conductive shell 3 of the high-voltage load is abnormal, so the control unit 5 can output a disconnection signal to the control circuit 2, and then the control circuit 2 responds to the disconnection signal to cut off the connection between the high-voltage power battery E1 and the multiple high-voltage loads. The disconnection signal in this embodiment can be a low-level signal or other control instructions, as long as it can ensure that the control circuit 2 can cut off the connection between the high-voltage power battery E1 and the multiple high-voltage loads in a timely manner.

[0067] In another embodiment, the control circuit can simultaneously disconnect the high-voltage power battery E1 from multiple high-voltage loads based on both the zero-drift voltage and a preset difference. Specifically, if the output voltage at the second terminal of the sampling resistor R exceeds the zero-drift voltage, and the absolute value of the difference between the output voltage and the supply voltage is less than the preset difference, the control circuit disconnects the high-voltage power battery E1 from the multiple high-voltage loads. This dual determination based on both the zero-drift voltage and the preset difference effectively improves the accuracy of disconnecting the high-voltage power battery E1 from the multiple high-voltage loads, avoids erroneous disconnections caused by voltage instability in the equipotential diagnostic system, and enhances the user experience.

[0068] In a specific embodiment, referring to Figure 2 The power supply is a low-voltage DC power supply E2, which is connected to the detection circuit 1 and the control circuit 2 respectively. The system also includes:

[0069] A low-voltage DC power supply E2 is connected to the detection circuit 1 and the control circuit 2, respectively, and serves as the power supply for the detection circuit 1 and the control circuit 2; a fuse box 6 is connected in series to the power supply line between the low-voltage DC power supply E2 and the detection circuit 1, and to the power supply line between the low-voltage DC power supply E2 and the control circuit 2, respectively; wherein the fuse box 6 is configured to cut off the power supply line when the power supply voltage output by the low-voltage DC power supply E2 to the detection circuit 1 and / or the control circuit 2 exceeds a preset voltage.

[0070] In this embodiment, combined with Figure 2 The system also includes a low-voltage DC power supply E2 and a fuse box 6. The low-voltage DC power supply E2 is connected to the detection circuit 1 and the control circuit 2 respectively, and can be used as a power supply to output a power supply voltage to the detection circuit 1 and the control circuit 2 respectively. The fuse box 6 is connected in series to the power supply line between the low-voltage DC power supply E2 and the control circuit 2. There is a fuse in the fuse box 6. When the power supply voltage output by the low-voltage DC power supply E2 to the detection circuit 1 or the control circuit 2 exceeds a preset voltage, the preset voltage is the maximum voltage allowed to pass by the detection circuit 1 and the control circuit 2. In order to protect the detection circuit 1 and the control circuit 2, when the power supply voltage exceeds the preset voltage, the fuse in the fuse box 6 will be disconnected, cutting off the power supply line.

[0071] In a specific embodiment, referring to Figure 3 , Figure 3 It is aimed at Figure 2 Detailed module diagram of the control circuit, the control circuit 2 includes: a second switch unit 7 and a third switch unit 8, the second switch unit 7 is connected in series on the first power supply circuit between the power supply source and the third switch unit 8, and the third switch unit 8 is also connected in series on the second power supply circuit between the high-voltage power battery E1 and multiple high-voltage loads; wherein, the second switch unit 7 is configured to be disconnected when the output voltage of the detection circuit 1 is higher than the zero-drift voltage to cut off the first power supply circuit; the third switch unit 8 is configured to disconnect the second power supply circuit when the first power supply circuit is cut off; and, is configured to turn on the second power supply circuit when the first power supply circuit is turned on.

[0072] In this embodiment, combined with Figure 3 The second switch unit 7 is connected in series to the first power supply circuit between the power supply and the third switch unit 8, and the third switch unit 8 is connected in series to the second power supply circuit between the high-voltage power battery E1 and multiple high-voltage loads. The second switch unit 7 can be used to cut off the first power supply circuit, and the third switch unit 8 can be used to cut off the second power supply circuit. Therefore, when the output voltage of the detection circuit 1 is higher than the zero drift voltage, the first power supply circuit is cut off, so that the power supply stops outputting the power supply voltage to the third switch unit 8. When the third switch unit 8 has no power supply voltage input, the first power supply circuit will also be automatically cut off, and then the high-voltage power battery E1 will stop outputting high voltage to multiple high-voltage loads. Correspondingly, when the first power supply circuit is turned on, the power supply will output the power supply voltage to the third switch unit 8. When the third switch unit 8 has a power supply voltage input, the second power supply circuit will be turned on to maintain or start the high-voltage power battery E1 to output high voltage to multiple loads.

[0073] In a specific embodiment, referring to Figure 3The third switch unit 8 includes a first relay K1 and a second relay K2; wherein the first relay K1 is connected between the positive electrode of the high-voltage power battery E1 and multiple high-voltage loads; the second relay K2 is connected between the negative electrode of the high-voltage power battery E1 and multiple high-voltage loads; the control end of the first relay K1 and the control end of the second relay K2 are both connected to the output end of the second switch unit 7; the second switch unit 7 also includes an input end and a control end, the input end of the second switch unit 7 is connected to the power supply, and the control end of the second switch unit 7 is connected to the output end of the detection circuit 1.

[0074] In this embodiment, combined with Figure 3 The third switch unit 8 includes a first relay K1 and a second relay K2. The first relay K1 is connected between the positive electrode of the high-voltage power battery E1 and multiple high-voltage loads, and the second relay K2 is connected between the negative electrode of the high-voltage power battery E1 and the multiple high-voltage loads. The control ends of the first relay K1 and the second relay K2 are connected to the output end of the second switch unit 7. The conduction and shutdown of the first relay K1 and the second relay K2 are controlled by the output voltage of the second switch unit 7, and the conduction and shutdown of the second switch unit 7 are controlled by the output voltage of the output end of the detection circuit 1.

[0075] In a specific embodiment, referring to Figure 3 The second switch unit 7 includes a first transistor Q1 and a second transistor Q2, wherein the collector of the first transistor Q1 and the collector of the second transistor Q2 are respectively connected to the power supply, and the base of the first transistor Q1 and the base of the second transistor Q2 are respectively connected to the output end of the detection circuit 1; the emitter of the first transistor Q1 is connected to the control end of the first relay K1, and the emitter of the second transistor Q2 is connected to the control end of the second relay K2; the first transistor Q1 is configured to control the first relay K1 to disconnect from the positive electrode of the high-voltage power battery E1 when the output voltage of the detection circuit 1 is higher than the zero-drift voltage; the second transistor Q2 is configured to control the second relay K2 to disconnect from the negative electrode of the high-voltage power battery E1 when the output voltage of the detection circuit 1 is higher than the zero-drift voltage.

[0076] In this embodiment, the second switch unit 7 includes a first transistor Q1 and a second transistor Q2. The first transistor Q1 and the second transistor Q2 are connected to each other to configure their respective functions. The first transistor Q1 controls the on / off state of the first relay K1, and the second transistor Q2 controls the on / off state of the second relay K2. Therefore, when the output voltage of the detection circuit 1 is higher than the zero-drift voltage, the first relay K1 is controlled to be off, so that the power supply voltage output by the power supply source cannot be output to the control terminal of the first relay K1. When the control terminal of the first relay K1 does not receive the power supply voltage, it automatically disconnects from the positive electrode of the high-voltage power battery E1. At the same time, when the output voltage of the detection circuit 1 is higher than the zero-drift voltage, the second transistor Q2 controls the second relay K2 to be off, so that the power supply voltage output by the power supply source cannot be output to the control terminal of the second relay K2. When the control terminal of the second relay K2 does not receive the power supply voltage, it automatically disconnects from the negative electrode of the high-voltage power battery E1.

[0077] In a specific embodiment, referring to Figure 3 The second switch unit 7 further includes a third transistor Q3; the third switch unit 8 further includes a pre-charging relay K3 and a pre-charging resistor R0, wherein the collector of the third transistor Q3 is connected to the power supply, the base of the third transistor Q3 is connected to the output end of the detection circuit 1, and the emitter of the third transistor Q3 is connected to the control end of the pre-charging relay K3; the pre-charging relay K3 is connected between multiple high-voltage loads and the first end of the pre-charging resistor R0, and the second end of the pre-charging resistor R0 is connected to the positive electrode of the high-voltage power battery E1; the second transistor Q2 is further configured to close when the output voltage of the detection circuit 1 is lower than or equal to the zero-drift voltage and the first relay K1 is not energized, thereby controlling the second relay K2 to be energized; the third transistor Q3 is configured to close when the second relay K2 is energized and the first relay K1 is not energized, thereby controlling the pre-charging relay K3 to be energized; the pre-charging resistor R0 is configured to stabilize the voltage output by the high-voltage power battery E1 in response to the energization of the second relay K2 and the pre-charging relay K3.

[0078] In this embodiment, the second switch unit 7 further includes a third transistor Q3, and the third switch unit 8 further includes a pre-charge resistor R0 and a pre-charge relay K3. Figure 3The connection relationship between the third transistor Q3, the pre-charge resistor R0 and the pre-charge relay K3 is that before the high-voltage power battery E1 outputs a high voltage to supply power to multiple high-voltage loads, in order to avoid the transient high voltage output by the high-voltage power battery E1 causing a high-voltage impact on the high-voltage load and damaging the high-voltage load, before supplying power to multiple high-voltage loads, the detection circuit 1 will first be used to detect whether the equipotential connection of the high-voltage load is normal. Under normal circumstances, it can also be understood that the output voltage of the detection circuit 1 is lower than or equal to the zero-drift voltage, then the first relay K1 is closed before it is attracted, and the circuit between the power supply and the second relay K2 can be turned on, and the power supply outputs power to the control end of the second relay K2. When the second relay K2 is closed, the third transistor Q3 is also closed. At this time, the power supply outputs the power supply voltage to the control end of the pre-charging relay K3, controlling the pre-charging relay K3 to be closed. At this time, through the attraction of the pre-charging relay K3 and the second relay K2, the high-voltage power battery E1 will output a high voltage to the pre-charging resistor R0. The pre-charging resistor R0 can pre-charge the voltage output by the high-voltage power battery E1 to avoid the transient high voltage output by the high-voltage power battery E1 from being transmitted to multiple high-voltage loads, stabilize the voltage output by the high-voltage power battery E1, and avoid the transient high voltage output by the high-voltage power battery E1 from supplying power to the high-voltage loads and damaging the high-voltage loads.

[0079] In a specific embodiment, referring to Figure 2 A detection circuit 1 is provided in the high-voltage power battery E1, wherein the detection circuit 1 is respectively connected to the conductive shell of the high-voltage power battery E1, the power supply and the second switch unit 7.

[0080] In this embodiment, a detection circuit 1 may also be provided in the high-voltage power battery E1. The detection circuit 1 is respectively connected to the conductive shell of the high-voltage power battery E1, the power supply and the second switch unit 7. The conductive shell of the high-voltage power battery E1 may also be subjected to equipotential detection. When it is detected that the output voltage of the detection circuit 1 connected to the conductive shell of the high-voltage power battery E1 is higher than the zero-drift voltage, the connection between the high-voltage power battery E1 and the plurality of high-voltage loads may be cut off through the control circuit 2.

[0081] For example, refer to Figure 4 , Figure 4 This is a schematic diagram of the circuit structure of an equipotential diagnostic system provided in an embodiment of the present application, combined with Figure 2 and Figure 3 ,from Figure 4It can be seen that the 12V lead-acid battery on the vehicle serves as a low-voltage power supply for the detection circuit 1 and the control circuit 2. The positive pole of the low-voltage power supply is respectively connected to the first switch unit 4 and the first transistor Q1, the second transistor Q2 and the third transistor Q3. Multiple high-voltage loads are connected in parallel with the first relay K1, the second relay K2 and the pre-charge relay K3. The negative pole of the low-voltage power supply E1, the conductive shell 3 of the high-voltage load, and the conductive shell of the high-voltage power battery E1 are respectively connected to the vehicle body at the same potential. The detection circuit 1 is respectively provided in the high-voltage load and the high-voltage power battery E1, and the control circuit 2 can be set close to the high-voltage power battery E1.

[0082] Therefore, when the vehicle is powered on at low voltage, each detection circuit 1 detects whether the equipotential connection of the conductive housing 3 of the corresponding high-voltage load or the conductive housing of the high-voltage power battery E1 is normal.

[0083] The following will take high voltage load 1 as an example to further explain:

[0084] After the vehicle is powered on (low-voltage power-up), the vehicle control system outputs a power-on signal to the control unit 5 in the detection circuit 1. The control unit 5 then outputs a voltage to the first switch unit 4, turning it on. This allows the low-voltage power supply to output the supply voltage to the sampling resistor R via the first switch unit 4. Simultaneously, the control unit 5 also collects the output voltage at the second end of the sampling resistor R, using it as a basis for comparison with the zero-drift voltage. When the output voltage at the second end of the sampling resistor R is lower than or equal to the zero-drift voltage, it indicates that the equipotential connection of the high-voltage load 1 is good, and disconnection between the high-voltage power battery E1 and the multiple high-voltage loads is not necessary. In this embodiment, the first switch unit 4 is a transistor.

[0085] Since the low-voltage power supply is 12V, the sampling point voltage is generally 0~1V (considering zero drift), which means the equipotential connection is good; the sampling point voltage is 1~11V, which means the equipotential contact is poor; the sampling point voltage is 12V, which means the equipotential connection is disconnected. When the output voltage at the second end of the sampling resistor R is higher than the zero-drift voltage, to avoid electric shock, regardless of whether the equipotential contact is poor or the equipotential connection is disconnected, the connection between the high-voltage power and the multiple high-voltage loads needs to be disconnected. At this time, the control unit 5 will output a low-level signal to the second switch unit 7 in the control circuit 2 via a communication line (not shown in the figure). The second switch unit 7 is composed of a first transistor Q1, a second transistor Q2, and a third transistor Q3. Specifically, the control unit 5 can output a low-level signal to the base of each transistor to switch the second switch unit 7 from a conductive state to a static state, thereby disconnecting the second circuit of the output power supply voltage from the low-voltage power supply to the third switch unit 8. When no power supply voltage passes through, the control ends of the first relay K1, the second relay K2, and the pre-charge relay K3 in the third switch unit 8 are in a disconnected state, thereby automatically disconnecting the connection between the high-voltage power battery E1 and the multiple high-voltage loads. This solves the problem that the insulation monitoring cannot diagnose load insulation failure when the high voltage is not powered on and the diagnosis time is long.

[0086] An embodiment of the present application further provides a vehicle, which includes the equipotential diagnostic system described in the embodiment.

[0087] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0088] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0089] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "includes," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, article, or terminal device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, article, or terminal device. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of additional identical elements in the process, article, or terminal device that includes the element.

[0090] The above is a detailed introduction to an equipotential diagnostic system and a vehicle provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. An equipotential diagnostic system, characterized in that: A power supply system for a vehicle, comprising a high-voltage power battery (E1) and a plurality of high-voltage loads connected to the high-voltage power battery (E1), the system comprising: A detection circuit (1) is located on at least one of the high-voltage loads and is connected between a power supply and a conductive housing (3) of the high-voltage load, the conductive housing also being connected to the vehicle body at an equipotential level; A control circuit (2) is connected in series to a connection line between the high-voltage power battery (E1) and the high-voltage load, and an input end of the control circuit (2) is connected to an output end of the detection circuit (1); The detection circuit (1) is configured to be turned on in response to a power-on signal of the vehicle; The control circuit (2) is configured to cut off the connection between the high-voltage power battery (E1) and the plurality of high-voltage loads when the output voltage of the detection circuit (1) is higher than the zero-drift voltage; The zero-drift voltage is a voltage indicating that the equipotential connection is normal.

2. The system according to claim 1, wherein: The detection circuit (1) comprises: a first switch unit (4) and a sampling resistor (R); the first switch unit (4) is connected in series between the power supply and the first end of the sampling resistor (R), and the second end of the sampling resistor (R) is connected to the conductive housing (3) of the high-voltage load; wherein, The first switch unit (4) is configured to be turned on in response to the power-on signal, so that the power supply outputs a supply voltage to the first end of the sampling resistor (R); The control circuit (2) is configured to cut off the connection between the high-voltage power battery (E1) and the plurality of high-voltage loads when the output voltage at the second end of the sampling resistor (R) is higher than the zero-drift voltage.

3. The system according to claim 2, characterized in that The detection circuit (1) further includes: a control unit (5), the control unit (5) being connected in parallel between the input end of the first switch unit (4) and the second end of the sampling resistor (R), and connected to the control circuit (2); wherein, The control unit (5) is configured to output a disconnection signal to the control circuit (2) when the absolute value of the difference between the output voltage and the supply voltage is less than a preset difference; The control circuit (2) is further configured to cut off the connection between the high-voltage power battery (E1) and the plurality of high-voltage loads in response to the disconnection signal.

4. The system according to claim 2, wherein: The power supply is a low-voltage DC power supply (E2), and the low-voltage DC power supply (E2) is connected to the detection circuit (1) and the control circuit (2) respectively; the system further includes: A fuse box (6) is connected in series to the power supply line between the low-voltage DC power supply (E2) and the detection circuit (1), and the power supply line between the low-voltage DC power supply (E2) and the control circuit (2); The fuse box (6) is configured to cut off the power supply line when the power supply voltage output by the low-voltage DC power supply (E2) to the detection circuit (1) and / or the control circuit (2) exceeds a preset voltage.

5. The system according to claim 1, wherein: The control circuit (2) comprises: a second switch unit (7) and a third switch unit (8), wherein the second switch unit (7) is connected in series to a first power supply circuit between the power supply source and the third switch unit (8), and the third switch unit (8) is further connected in series to a second power supply circuit between the high-voltage power battery (E1) and the plurality of high-voltage loads; Wherein, the second switch unit (7) is configured to be disconnected when the output voltage of the detection circuit (1) is higher than the zero-drift voltage, so as to cut off the first power supply circuit; The third switch unit (8) is configured to disconnect the second power supply circuit when the first power supply circuit is disconnected; and is configured to connect the second power supply circuit when the first power supply circuit is connected.

6. The system according to claim 5, characterized in that The third switch unit (8) includes a first relay (K1) and a second relay (K2); wherein, The first relay (K1) is connected between the positive electrode of the high-voltage power battery (E1) and the plurality of high-voltage loads; the second relay (K2) is connected between the negative electrode of the high-voltage power battery (E1) and the plurality of high-voltage loads; The control end of the first relay (K1) and the control end of the second relay (K2) are both connected to the output end of the second switch unit (7); The second switch unit (7) further comprises an input end and a control end, the input end of the second switch unit (7) is connected to the power supply, and the control end of the second switch unit (7) is connected to the output end of the detection circuit (1).

7. The system according to claim 6, characterized in that The second switch unit (7) comprises a first transistor (Q1) and a second transistor (Q2), wherein: The collector of the first transistor (Q1) and the collector of the second transistor (Q2) are respectively connected to the power supply, and the base of the first transistor (Q1) and the base of the second transistor (Q2) are respectively connected to the output end of the detection circuit (1); The emitter of the first transistor (Q1) is connected to the control end of the first relay (K1), and the emitter of the second transistor (Q2) is connected to the control end of the second relay (K2); The first transistor (Q1) is configured to control the first relay (K1) to disconnect the positive electrode of the high-voltage power battery (E1) when the output voltage of the detection circuit (1) is higher than the zero-drift voltage; The second transistor (Q2) is configured to control the second relay (K2) to disconnect from the negative electrode of the high-voltage power battery (E1) when the output voltage of the detection circuit (1) is higher than the zero-drift voltage.

8. The system according to claim 7, characterized in that The second switch unit (7) further includes a third transistor (Q3); the third switch unit (8) further includes a pre-charge relay (K3) and a pre-charge resistor (R0), wherein: The collector of the third transistor (Q3) is connected to the power supply, the base of the third transistor (Q3) is connected to the output end of the detection circuit (1), and the emitter of the third transistor (Q3) is connected to the control end of the pre-charge relay (K3); The pre-charging relay (K3) is connected between the plurality of high-voltage loads and a first end of the pre-charging resistor (R0), and the second end of the pre-charging resistor (R0) is connected to the positive electrode of the high-voltage power battery (E1); The second transistor (Q2) is further configured to close when the output voltage of the detection circuit (1) is lower than or equal to the zero-drift voltage and the first relay (K1) is not closed, and to control the second relay (K2) to close; The third transistor (Q3) is configured to close when the second relay (K2) is closed and the first relay (K1) is not closed, thereby controlling the pre-charge relay (K3) to be closed; The pre-charging resistor (R0) is configured to stabilize the voltage output by the high-voltage power battery (E1) in response to the engagement of the second relay (K2) and the pre-charging relay (K3).

9. The system according to claim 5, characterized in that The high-voltage power battery (E1) is provided with the detection circuit (1), wherein the detection circuit (1) is respectively connected to the conductive housing of the high-voltage power battery (E1), the power supply, and the second switch unit (7).

10. A vehicle, characterized in that: The vehicle comprises the equipotential diagnostic system according to any one of claims 1 to 9.

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