An electric vehicle high-voltage short-circuit protection device, system and control method

Abstract

The application relates to an electric vehicle high-voltage short-circuit protection device, system and control method, which comprises a shell, a contactor, a current sensor and a control board arranged in the shell; the shell is provided with a positive contact point and a negative contact point for connecting high-voltage load circuits on the vehicle in series; the contactor is used for turning on or turning off the positive contact point and the negative contact point; the current sensor is used for detecting real-time current values of high-voltage circuits; the control board is provided with a current threshold value, which is used for comparing the real-time current values with the current threshold value, and when the real-time current values are greater than the current threshold value, the control board controls the contactor to turn off the positive contact point and the negative contact point, and sends a fault alarm signal to an upper computer through a communication interface; when the scheme occurs short circuit, millisecond-level autonomous physical cutting and active fault state reporting can be realized.

Description

Technical Field

[0001] This invention belongs to the field of high-voltage safety technology for electric vehicles, and particularly relates to a high-voltage short-circuit protection device, system and control method for electric vehicles. Background Technology

[0002] In recent years, the number of electric vehicles in my country has continued to grow, and the safety of electric vehicles has always been a top concern for consumers. Relevant plans are constantly improving standards related to high-voltage safety in electric vehicles. Among the many electric vehicle safety issues, a significant proportion are caused by short circuits in the circuits and loads outside the power battery pack during vehicle operation due to load insulation problems. This seriously threatens the lives and property of consumers, ranging from minor issues with battery cell consistency to serious accidents such as fires.

[0003] Currently, in the high-voltage system connection scheme of electric vehicles, the power battery system is typically equipped with a fuse and a main contactor in each branch, while each high-voltage load is also equipped with a fuse and a contactor. The fuse and contactor together provide protection and switching functions for the power supply circuit of the high-voltage system. The fuse is responsible for cutting off the high-voltage circuit by melting itself when an overcurrent or short circuit occurs in the circuit.

[0004] However, when selecting fuses for actual use, factors such as ambient temperature and thermal connections must be comprehensively considered, making the selection process cumbersome and prone to large calculation errors. In practical applications, to avoid malfunctions, fuses and contactors that are too large are often configured. This results in a relatively slow breaking response speed of the fuse when a momentary short circuit occurs in the high-voltage system. Before the fault current is cut off, the battery cells are easily impacted, causing inconsistencies. Some individual cells may even be damaged, and in more serious cases, this can directly lead to a vehicle fire. Summary of the Invention

[0005] In view of this, the present invention provides a high-voltage short-circuit protection device, system and control method for electric vehicles, which solves the problems of delayed response of fuses and lack of precise branch isolation protection when a short circuit occurs in the high-voltage circuit of an electric vehicle.

[0006] To achieve the above objectives, in a first aspect, the technical solution of the present invention to solve the technical problem is to provide a high-voltage short-circuit protection device for electric vehicles, comprising: a housing, and a contactor, a current sensor, and a control board disposed within the housing; the housing is provided with a positive contact and a negative contact for connecting the high-voltage load circuit of the vehicle in series; the contactor is used to connect or disconnect the positive contact and the negative contact; the current sensor is used to detect the real-time current value of the high-voltage circuit; the control board is preset with a current threshold, used to compare the real-time current value with the current threshold, and when the real-time current value is greater than the current threshold, to control the contactor to disconnect the positive contact and the negative contact, and simultaneously send a fault alarm signal to the host computer through a communication interface.

[0007] In one possible embodiment, the current sensor is a Hall current sensor, or a current acquisition circuit including a shunt and an acquisition module; the communication interface is a CAN bus communication interface, or an I / O interface for outputting high and low level signals.

[0008] In one possible embodiment, the control board is provided with a power supply port for connecting to a low-voltage power supply of the vehicle, which is a 12V, 24V, or 48V DC power supply.

[0009] Secondly, the present invention provides a high-voltage short-circuit protection system for electric vehicles, including a power battery, multiple high-voltage load circuits connected to the power battery, a storage battery, a vehicle controller, and short-circuit protection devices; the multiple short-circuit protection devices are respectively connected in series to the multiple high-voltage load circuits for connecting or disconnecting the high-voltage load circuits; the storage battery is connected to the multiple short-circuit protection devices for supplying power to the short-circuit protection devices; wherein, different current thresholds are preset on the control boards of the multiple short-circuit protection devices; all the short-circuit protection devices are communicatively connected to the vehicle controller through a communication interface.

[0010] In one possible embodiment, when there are at least two similar high-voltage load circuits, the similar high-voltage load circuits are connected in parallel to the same short-circuit protection device.

[0011] In one possible embodiment, during the high-voltage power-on phase, the vehicle controller sends a closing command to all the short-circuit protection devices through the communication interface, and each short-circuit protection device controls its internal contactor to close to connect its respective high-voltage load circuit.

[0012] In one possible embodiment, the high-voltage load circuit includes the high-voltage output circuit of each battery box in the power battery and the high-voltage input circuit of each high-voltage electrical load.

[0013] Thirdly, the present invention provides a high-voltage short-circuit protection control method for electric vehicles, comprising the following steps: configuring and writing the current threshold inside the short-circuit protection device on the corresponding branch according to the load characteristics of the high-voltage output circuit of each battery box in the power battery and the high-voltage input circuit of each high-voltage electrical equipment; after the vehicle is powered on at low voltage, the short-circuit protection device on each branch receives a closing command sent by the vehicle controller and controls the internal contactor to close to connect the corresponding high-voltage load circuit; during the operation of the high-voltage system, the short-circuit protection device on each branch independently and in real time collects the real-time current value in the high-voltage load circuit of its own branch; when any short-circuit protection device determines that the real-time current value of its own branch is greater than the current threshold preset for its own branch, the short-circuit protection device autonomously disconnects the contactor of its own branch to cut off the high-voltage load circuit of its own branch, and reports the fault signal of its own branch to the vehicle controller through the communication interface.

[0014] In one possible embodiment, after receiving the fault signal, the vehicle controller executes a system-level alarm or fault recording and locks the power-on operation of the corresponding branch.

[0015] In one possible embodiment, the short-circuit protection device on the branch that has not experienced a fault is not affected by the disconnection of the faulty branch and maintains the original closed power supply state.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: By integrating the current sensor and control board into the housing and linking them with the contactor, the control board uses preset thresholds to perform real-time current monitoring and rapid logic judgment, replacing the traditional fuse selection method which is greatly affected by the environment and has a slow response. In the event of a short circuit, it can achieve millisecond-level autonomous physical disconnection and actively report the fault status, which greatly improves the device's response speed, disconnection reliability and high-voltage protection safety level. Attached Figure Description

[0017] Figure 1 A schematic diagram of the structure of a short-circuit protection device for a high-voltage system of an electric vehicle provided by the present invention; Figure 2 A schematic diagram of a short-circuit protection system for a high-voltage system in an electric vehicle provided by the present invention; Figure 3 The present invention provides a flowchart of the steps of a short-circuit protection control method for a high-voltage system of an electric vehicle.

[0018] Explanation of reference numerals in the attached figures: 1. Housing; 2. Contactor; 3. Current sensor; 4. Control board; 7. Drive motor; 8. Air conditioner; 10. Power battery system; 11. Vehicle controller; 12. Battery. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0020] It should be noted that all directional indications in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0021] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of a person skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, the user should consider such a combination of technical solutions to be non-existent and not within the scope of protection claimed in this application.

[0022] like Figure 1 As shown, the first embodiment of the present invention provides a short-circuit protection device for a high-voltage system of an electric vehicle, which includes: a housing 1, and a contactor 2, a current sensor 3 and a control board 4 disposed in the housing 1; The housing 1 is provided with positive and negative contacts for connecting the high-voltage load circuit of the automobile in series; Contactor 2 is used to connect or disconnect the positive and negative contacts; Current sensor 3 is used to detect the real-time current value of the high-voltage circuit; The control board 4 has a preset current threshold, which is used to compare the real-time current value with the current threshold. When the real-time current value is greater than the current threshold, the control contactor 2 is controlled to disconnect the positive and negative contacts, and at the same time, a fault alarm signal is sent to the host computer through the communication interface.

[0023] Specifically, housing 1 is an insulated structure with a sealed internal cavity, within which contactor 2, current sensor 3, and control board 4 are all housed. Contactor 2 includes an electromagnetic coil, a return spring, an armature assembly, and metal contacts. The metal contacts are linked to the armature assembly. When energized, the electromagnetic coil drives the armature assembly to move, causing the metal contacts to contact the positive and negative contacts on housing 1. When de-energized, the return spring drives the armature assembly to reset, causing the metal contacts to separate from the positive and negative contacts on housing 1. Thus, contactor 2 enables the connection or disconnection of the positive and negative contacts, i.e., the connection or disconnection of the high-voltage load circuit.

[0024] Current sensor 3 is installed on the high-voltage load circuit to collect real-time current data and send it to control board 4. Control board 4 has a pre-set current threshold based on load characteristics. When control board 4 detects that the collected real-time current value exceeds this threshold, it immediately cuts off the power supply to the coil of contactor 2, causing the internal reset spring of contactor 2 to actuate, forcibly separating the positive and negative contacts and cutting off the high-voltage power supply. Simultaneously, control board 4 sends this circuit-breaking action as a fault alarm signal to the host computer via the communication interface.

[0025] It should be noted that the metal contacts can have any structure, as long as they can conduct the high-voltage load circuit when in contact with the positive and negative contacts, and disconnect the high-voltage load circuit when separated from the positive and negative contacts.

[0026] Contactor 2 can be an electromagnetic relay or a high-power solid-state relay, as long as it can connect or disconnect the high-voltage load circuit under the drive of control board 4.

[0027] The control board 4 can be a microcontroller unit (MCU) or a hardware logic gate comparison circuit. It can only preset the current threshold and output a control signal based on the comparison result between the real-time current value and the current threshold.

[0028] By highly integrating the contactor 2, current sensor 3, and control board 4 into the insulating and sealed housing 1, and relying on the mechanical cooperation of the electromagnetic coil excitation driving the armature to physically disengage from the reset spring, the traditional fuse, which is greatly affected by ambient temperature and has a complex selection process, is replaced. This achieves millisecond-level autonomous physical disconnection during overcurrent or short circuit and can actively report the fault status to the vehicle controller 11, thereby improving the safety level of high-voltage protection.

[0029] In an optional embodiment, the current sensor 3 is a Hall current sensor, or a current acquisition circuit based on a shunt and an acquisition module; the communication interface is a CAN (Controller Area Network) bus communication interface, or an I / O interface for outputting high and low level signals.

[0030] Specifically, when the current sensor 3 uses a Hall sensor, it achieves non-contact measurement with no insertion loss; when using a shunt solution, it achieves low-cost, high-precision current detection by using a series precision resistor in conjunction with the acquisition module. The communication interface can use the CAN bus commonly used in vehicles for bidirectional data exchange with the host computer, or it can directly trigger external alarm hardware via high and low voltage levels.

[0031] It should be noted that the current sensor 3 can also use a TMR (tunnel magnetoresistive) current sensor to obtain higher measurement accuracy and signal-to-noise ratio. The communication interface can also be replaced with a LIN bus communication interface to adapt to cheaper low-voltage communication networks.

[0032] By offering two hardware options (Hall effect / shunt) and two network configuration paths (CAN bus / high / low level), the universality and compatibility of this protection device are greatly enhanced across vehicles with different cost profiles and electronic control architectures.

[0033] In an optional embodiment, the control board 4 is provided with a power supply port for connecting to the vehicle's low-voltage power supply, which is a 12V, 24V, or 48V DC power supply.

[0034] Specifically, control board 4 is connected to the vehicle's independent low-voltage power supply (e.g., 24V battery 12) via its own power supply port. After the vehicle starts, it is powered by the low-voltage battery and activated. Control board 4 integrates a wide voltage input voltage regulator module, which is compatible with various vehicle models from 12V to 48V.

[0035] It should be noted that the power supply port of board 4 can directly draw from the auxiliary step-down power supply with high voltage output, without the need for an external independent low voltage power supply; the interior of housing 1 can also be filled with high thermal conductivity insulating potting compound to further enhance the overall waterproof, dustproof and shockproof performance of the device.

[0036] like Figure 2 As shown, the second embodiment of the present invention provides a short-circuit protection system for a high-voltage system of an electric vehicle, which includes: a power battery 10, a plurality of high-voltage load circuits connected to the power battery 10, a vehicle controller 11, a storage battery 12, and a short-circuit protection device. Multiple short-circuit protection devices are connected in series to multiple high-voltage load circuits to connect or disconnect the high-voltage load circuits. The storage battery is connected to multiple short-circuit protection devices to supply power to them; Among them, different current thresholds are preset on the control board 4 of multiple short-circuit protection devices; All short-circuit protection devices are connected to the vehicle controller 11 via a communication interface.

[0037] Specifically, the power battery supplies power to loads such as the drive motor 7, air conditioner 8, or other loads through multiple high-voltage load circuits. Each high-voltage load circuit is connected in series with a short-circuit protection device for independent monitoring.

[0038] The low-voltage power supplied by battery 12 is directly delivered to the control board 4 of each short-circuit protection device, ensuring that it can enter standby mode before the vehicle is powered on with high voltage. The current threshold written inside each short-circuit protection device is configured independently during the vehicle assembly stage based on the actual power characteristics and overload capacity of the corresponding load in the high-load circuit. Therefore, the current thresholds of different branches are different. At the same time, all short-circuit protection devices are connected to the vehicle controller 11 via the CAN bus, forming a global low-voltage communication network.

[0039] By independently deploying short-circuit protection devices with dedicated current thresholds on each high-voltage load circuit, the system possesses distributed protection capabilities of "multi-point independent judgment and local fault isolation," significantly improving the reliability and fault tolerance of the vehicle's high-voltage system.

[0040] In an optional embodiment, when there are at least two similar high-voltage load circuits, the similar high-voltage load circuits are connected in parallel to the same short-circuit protection device.

[0041] Specifically, in the vehicle's electrical architecture, there are often two high-voltage loads of the same specifications (such as dual DC / AC inverters or dual high-voltage PTC heaters) to improve the vehicle's power output or provide redundancy. In this case, the input terminals of these two similar loads can be connected in parallel to the same high-voltage load circuit, and the preset current threshold of the short-circuit protection device corresponding to the high-voltage load circuit can be set to the total maximum current when the two parallel loads are working simultaneously.

[0042] It should be noted that if the vehicle has extremely high fault tolerance requirements for the failure of a single load, a short-circuit protection device can be independently configured for each of the two parallel loads of the same type, forming a dual redundancy protection structure.

[0043] Depending on the specific needs of the vehicle's electrical architecture, the "single device co-protection" or "independent device redundancy" can be flexibly selected, which not only achieves effective protection for similar equipment, but also saves on the number of short-circuit protection devices and the cost of the vehicle's wiring harness when extreme redundancy is not required.

[0044] In an optional embodiment, during the high-voltage power-on phase, the vehicle controller 11 sends a closing command to all short-circuit protection devices via a communication interface, and each short-circuit protection device controls its internal contactor 2 to close to connect its respective high-voltage load circuit.

[0045] Specifically, when the driver starts the vehicle and the battery 12 supplies power, the vehicle controller 11 completes its self-test and determines that the high-voltage power-on safety conditions are met. Then, it sends a closing command to the short-circuit protection devices on each branch simultaneously through the CAN communication network. After receiving the command, the control board 4 of each short-circuit protection device drives the electromagnetic coil of the contactor 2 to be energized and engaged, thereby energizing the high-voltage loads on each branch synchronously.

[0046] It should be noted that the closing command can also use a 24V high-level hard-wired signal instead of a CAN communication message to further improve power-on reliability in extremely harsh electromagnetic environments. The closing time of each high-voltage load circuit can also be staggered by the vehicle controller 11 to avoid instantaneous peak current surges to the power battery 10 caused by multiple high-power loads being powered on simultaneously.

[0047] The vehicle controller 11 centrally manages the power-on sequence and closing action of the short-circuit protection devices of each branch, ensuring that the high-voltage circuit of the vehicle is connected to the power battery 10 in an orderly, controlled and safe manner, avoiding high-voltage misconnection or surge impact.

[0048] In an optional embodiment, the high-voltage load circuit includes the high-voltage output circuit of each battery box in the power battery 10 and the high-voltage input circuit of each high-voltage electrical load.

[0049] Specifically, the high-voltage load circuits in the entire system are divided into two main categories: one is the charging and discharging output circuit of the battery box itself inside the power battery 10, and the other is the input power circuit of various external high-voltage loads (drive motor 7, air conditioner 8, etc.). Short-circuit protection devices are independently connected in series in both types of circuits to monitor them.

[0050] like Figure 3 As shown, the third embodiment of the present invention also provides a short-circuit protection control method for a high-voltage system of an electric vehicle, including the following steps: S100, based on the load characteristics of the high voltage output circuit of each battery box in the power battery 10 and the high voltage input circuit of each high voltage load, respectively configure and write the current threshold inside the short circuit protection device on the corresponding branch. During the offline calibration phase of the system, technicians calculated the safety protection thresholds for the circuits of different loads such as drive motor 7, air conditioner 8, and battery box, based on parameters such as the starting peak value and continuous operating current. These thresholds were then programmed into the internal chip of the control board 4 of the short-circuit protection device for each corresponding branch.

[0051] It should be noted that this current threshold can also be updated online via the vehicle's OTA remote upgrade technology during subsequent use, by the back-end cloud to adapt to changes in battery capacity due to aging or special needs of driving modes.

[0052] S200, after the vehicle is powered on at low voltage, the short circuit protection device on each branch receives the closing command sent by the vehicle controller 11 and controls the internal contactor 2 to close to connect the corresponding high voltage load circuit. After the battery 12 supplies power to the control boards 4 of each short-circuit protection device, each short-circuit protection device is in a standby listening state. When the vehicle controller 11 confirms that there is no major fault in the vehicle, it sends a unified closing command through the CAN bus, and each branch control board 4 then drives the electromagnetic coil of the contactor 2 to be energized and engaged, and the power battery 10 begins to supply power to each load circuit.

[0053] S300: During high-voltage system operation, the short-circuit protection device on each branch independently and in real time collects the real-time current value in the high-voltage load circuit of its own branch. During vehicle operation or charging, current sensor 3 is always in a high-frequency working state, collecting current data of its branch at a frequency of milliseconds or even microseconds, and performing real-time filtering and processing inside control board 4. It does not rely on polling feedback from vehicle controller 11, thus ensuring the independence of system judgment.

[0054] It should be noted that the sampling frequency of the current sensor 3 can also be adaptively adjusted according to the load operating status. For example, the sampling frequency can be reduced under non-peak conditions to reduce its own power consumption.

[0055] S400, when any short-circuit protection device determines that the real-time current value of this branch is greater than the preset current threshold of this branch, the short-circuit protection device automatically disconnects the contactor 2 of this branch to cut off the high-voltage load circuit of this branch, and reports the fault signal of this branch to the vehicle controller 11 through the communication interface. When a short circuit or severe overload occurs, the control board 4 directly triggers a logic judgment locally. Once it is confirmed that the real-time current value exceeds the limit, the control board 4 immediately cuts off the electromagnetic coil current of the contactor 2. The reset spring inside the contactor 2 uses mechanical elasticity to instantly push the armature assembly to reset. The armature assembly causes the metal contacts inside the contactor 2 to separate from the positive and negative contacts on the housing 1, achieving physical isolation of the high voltage.

[0056] At the same time, the short-circuit protection device will actively send a message containing the fault branch number, fault type and operating current value to the vehicle controller 11 and wait for processing feedback.

[0057] It should be noted that when the judgment result is a minor overload rather than a severe short circuit, the control board 4 can first output a PWM high-frequency pulse suppression strategy for a period of time to try to avoid instantaneous surges before judging whether to disconnect, so as to avoid frequent false tripping.

[0058] By implementing a closed-loop logic of independent detection, local judgment, autonomous disconnection, and centralized reporting through the short-circuit protection devices of each branch, millisecond-level response of protection actions is achieved, greatly shortening the fault clearing time.

[0059] In an optional embodiment, after receiving the fault signal, the vehicle controller executes a system-level alarm or fault recording and locks the power-on operation of the corresponding branch.

[0060] Upon receiving a fault report, the vehicle controller 11 first activates the audible and visual alarms on the vehicle's instrument panel to alert the driver. Simultaneously, it records the timestamp of the fault occurrence, the branch location, and current information into the vehicle's fault black box. To prevent the faulty branch from being accidentally reset before the potential hazard has been completely eliminated, the vehicle controller 11 locks the power-on flag of that branch in its memory. Unless manually cleared by maintenance personnel or unlocked by a command, that branch will no longer be able to close contactor 2 again.

[0061] It should be noted that after receiving a fault signal, the vehicle controller 11 can also simultaneously limit the total discharge power output of the power battery 10 according to the severity of the fault, so as to reduce the overall load of the vehicle.

[0062] By executing the locking and alarm commands from the host computer through the vehicle controller 11, the fault status is ensured to be controlled and traceable, preventing the risk of secondary short circuits caused by electrical reset of the faulty branch.

[0063] In an optional embodiment, the short-circuit protection device on the branch that has not experienced a fault is not affected by the disconnection of the faulty branch and maintains the original closed power supply state.

[0064] After the faulty branch is isolated, the real-time current values ​​of the remaining high-voltage load circuits on the high-voltage busbar of the vehicle, where the power battery 10 is located, remain within their preset current threshold ranges. Therefore, the short-circuit protection devices on these branches will not misjudge or malfunction, and their contactors 2 will remain closed. Each unfaulty high-voltage electrical load (such as the drive motor 7, air conditioner 8, etc.) can continue to draw power normally from the busbar, ensuring that the vehicle still has the ability to drive and maintain basic safety functions.

[0065] It should be noted that after receiving a single branch fault, the vehicle controller 11 can also send a power reduction command to other branches that have not exceeded the limit to cooperate with the local output capacity fluctuation of the power battery 10 caused by the short circuit of a single branch, thereby achieving coordinated degrade control at the vehicle level.

[0066] By ensuring the independence of each branch short-circuit protection device, precise isolation is achieved based on the fault location, effectively solving the defect of "branch short circuit, whole vehicle high voltage cut-off" in the traditional single relay protection mode, and improving the vehicle's survival and self-protection capabilities in the event of a sudden high-voltage short circuit.

[0067] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A high-voltage short-circuit protection device for electric vehicles, characterized in that, Includes: a housing, and a contactor, a current sensor, and a control board disposed within the housing; The housing is provided with positive and negative contacts for connecting the high-voltage load circuit of the vehicle in series. The contactor is used to connect or disconnect the positive contact and the negative contact; The current sensor is used to detect the real-time current value of the high-voltage circuit; The control board has a preset current threshold, which is used to compare the real-time current value with the current threshold. When the real-time current value is greater than the current threshold, the control board controls the contactor to disconnect the positive and negative contacts and sends a fault alarm signal to the host computer through the communication interface.

2. The electric vehicle high-voltage short-circuit protection device as described in claim 1, characterized in that: The current sensor is a Hall current sensor, or a current acquisition circuit including a shunt and an acquisition module; the communication interface is a CAN bus communication interface, or an I / O interface for outputting high and low level signals.

3. The electric vehicle high-voltage short-circuit protection device as described in claim 1, characterized in that: The control board is equipped with a power supply port for connecting to the vehicle's low-voltage power supply, which is a 12V, 24V, or 48V DC power supply.

4. A high-voltage short-circuit protection system for an electric vehicle, comprising a power battery, multiple high-voltage load circuits connected to the power battery, a storage battery, and a vehicle controller, characterized in that, It also includes a plurality of short-circuit protection devices as described in any one of claims 1-3; Multiple short-circuit protection devices are connected in series to multiple high-voltage load circuits to connect or disconnect the high-voltage load circuits. The storage battery is connected to multiple short-circuit protection devices to supply power to the short-circuit protection devices. Different current thresholds are preset on the control boards of the multiple short-circuit protection devices; All of the short-circuit protection devices are connected to the vehicle controller via a communication interface.

5. The electric vehicle high-voltage short-circuit protection system as described in claim 4, characterized in that: When there are at least two high-voltage load circuits of the same type, the high-voltage load circuits of the same type are connected in parallel to the same short-circuit protection device.

6. The electric vehicle high-voltage short-circuit protection system as described in claim 4, characterized in that: During the high-voltage power-on phase, the vehicle controller sends a closing command to all the short-circuit protection devices through the communication interface, and each short-circuit protection device controls its internal contactor to close to connect its respective high-voltage load circuit.

7. The electric vehicle high-voltage short-circuit protection system as described in claim 4, characterized in that: The high-voltage load circuit includes the high-voltage output circuit of each battery box in the power battery and the high-voltage input circuit of each high-voltage electrical load.

8. A high-voltage short-circuit protection control method for an electric vehicle according to any one of claims 4-7, characterized in that, Includes the following steps: Based on the load characteristics of the high-voltage output circuit of each battery box in the power battery and the high-voltage input circuit of each high-voltage electrical equipment, the current threshold of the short-circuit protection device on the corresponding branch is configured and written into the device. After the vehicle is powered on at low voltage, the short-circuit protection device on each branch receives the closing command sent by the vehicle controller and controls the internal contactor to close to connect the corresponding high-voltage load circuit. During the operation of the high-voltage system, the short-circuit protection device on each branch independently and in real time collects the real-time current value in the high-voltage load circuit of its branch. When any of the short-circuit protection devices determines that the real-time current value of the branch is greater than the preset current threshold of the branch, the short-circuit protection device automatically disconnects the contactor of the branch to cut off the high-voltage load circuit of the branch, and reports the fault signal of the branch to the vehicle controller through the communication interface.

9. The high-voltage short-circuit protection control method for electric vehicles as described in claim 8, characterized in that: After receiving the fault signal, the vehicle controller executes a system-level alarm or fault record and locks the power-on operation of the corresponding branch.

10. The high-voltage short-circuit protection control method for electric vehicles as described in claim 8, characterized in that: The short-circuit protection device on the branch that has not experienced a fault is not affected by the disconnection of the faulty branch and maintains the original closed power supply state.

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