Vehicle electric drive system collision power-off protection device and method

Abstract

The embodiment of the invention provides a vehicle electric drive system collision power-off protection device and method. The device comprises a high-voltage bus, a drive board and a power-off execution unit. And the high-voltage bus is connected with a bus port of the driving board through a dense spot welding assembly in the fusing area. The power-off execution unit comprises a control module, a collision information acquisition module and a fuse. The control module can obtain vehicle collision information detected by the collision information acquisition module, and when the vehicle collision information is larger than a collision threshold value, a starting instruction is sent to the fuse, so that the execution end of the fuse generates fusing temperature rise in a fusing area, and the dense spot welding assembly is fused. The device can realize connection by adopting a dense spot welding mode at the joint of the high-voltage bus and the bus port of the driving plate, and controls the fuse to fuse the dense spot welding position according to acceleration information during collision, so that electrical connection of an electric driving system is cut off, and the risk of a secondary accident of a vehicle is reduced.

Description

Technical Field

[0001] The present application relates to the field of vehicle safety control technology, and in particular to a collision power-off protection device and method for a vehicle electric drive system. Background Art

[0002] Vehicles, especially electric vehicles and hybrid vehicles, include electric drive systems. Vehicle electric drive systems may include electric motors, electric controllers, transmissions, batteries, cooling systems, on-board chargers, high-voltage power distribution units, software control units, and mechanical structures. Due to the presence of high-voltage devices in the electric drive system, vehicles are prone to secondary accidents such as brake failure and fire caused by excessive current inside the vehicle when they collide, which directly affects the competitiveness of the automotive industry and the safety of life and property of users.

[0003] In order to improve the safety of the vehicle during a collision, the electric drive system can be equipped with a collision power-off protection device. The collision power-off protection device can send an ignition signal through the vehicle's ignition signal control device to detonate the detonating agent in the cartridge and generate a large amount of gas in a short period of time. The generated gas forms a strong air pressure in the cavity, which pushes the fuse to move, thereby cutting off the circuit and cutting off the power of the vehicle, preventing secondary accidents caused by the circuit inside the vehicle.

[0004] However, the protective device that relies on an ignition signal to detonate the explosive, thereby pushing the fuse to detach and cutting off the electrical connection of the circuit to achieve power-off due to collision, cannot judge the degree of collision, and cannot set the ignition threshold according to the degree of collision. It is difficult to achieve precise control of power-off due to collision. At the same time, this solution is only applicable to power-off of low-voltage circuits. The distance between the fuses after cutting off is relatively close, and the strong current will break through the air and continue to supply power, causing the power-off protection function to fail. Summary of the invention

[0005] In view of this, an embodiment of the present application provides a collision power-off protection device and method for a vehicle electric drive system. The power-off protection device has the problem that the power-off protection function fails under high voltage conditions.

[0006] According to one aspect of the present application, a collision power-off protection device for a vehicle electric drive system is provided, the device comprising:

[0007] High-voltage busbar, connected to vehicle power supply;

[0008] The driving board comprises a busbar port, wherein the high-voltage busbar is connected to the busbar port via a dense spot welding assembly; the dense spot welding assembly is arranged in a fuse area;

[0009] A power-off execution unit, comprising a control module, a collision information acquisition module and a fuse; the collision information acquisition module is connected to the control module; the fuse comprises a control end and an execution end, the control end of the fuse is connected to the control module, and the execution end of the fuse is arranged in the fuse region;

[0010] The collision information collection module is configured to collect vehicle collision information and send the collision information to the control module;

[0011] The control module is configured to:

[0012] Obtain vehicle collision information and preset collision threshold;

[0013] If the vehicle collision information is greater than the collision threshold, a start instruction is sent to the fuse, so that the execution end of the fuse generates a melting temperature rise in the melting area to melt the dense spot welding component.

[0014] Optionally, the device further comprises:

[0015] An electric energy sensor is connected to the control module; the electric energy sensor is configured to collect power-on information of the high-voltage bus and / or the drive board, and send the power-on information to the control module; the control module is further configured to:

[0016] receiving the power-on information;

[0017] If the power-on information indicates that the power supply has been cut off, a stop instruction is sent to the fuse to control the execution end of the fuse to stop generating a fusing temperature rise in the fusing area;

[0018] If the power-on information indicates that the power supply is not cut off, a continuous temperature rise instruction is sent to the fuse to control the execution end of the fuse to continuously generate a fusing temperature rise in the fusing area.

[0019] Optionally, the device further comprises:

[0020] a temperature sensor, arranged in the fuse area; the temperature sensor is connected to the control module, the temperature sensor is configured to collect temperature information in the fuse area, and send the temperature information to the control module; the control module is further configured to:

[0021] Acquiring the temperature information and a preset temperature threshold;

[0022] If the temperature information is greater than or equal to the temperature threshold, the step of receiving the power-on information is performed.

[0023] If the temperature information is less than the temperature threshold, the temperature information in the fuse area is continuously monitored.

[0024] Optionally, if the temperature information is less than the temperature threshold, the control module is further configured to:

[0025] Calculate the temperature rise per unit time;

[0026] If the temperature rise is less than a preset rise threshold, a re-start instruction is sent to the fuse to control the fuse to generate a melting temperature rise in the melting area to melt the dense spot welding assembly;

[0027] If the temperature increase is greater than or equal to the preset temperature increase threshold, performing the step of receiving the power-on information;

[0028] Optionally, the vehicle collision information includes acceleration information, and the control module is further configured to:

[0029] Obtaining historical acceleration information within the preset judgment period;

[0030] Setting the collision threshold according to the historical acceleration information;

[0031] If the vehicle collision information is less than or equal to the collision threshold, the acceleration information in the vehicle collision information is recorded to set the collision threshold in the next judgment cycle.

[0032] Optionally, the device further comprises:

[0033] A shielding box, wherein the control module is arranged in the shielding box;

[0034] The shielding box comprises a metal shielding layer and a through hole, wherein the metal shielding layer is arranged at the periphery of the control module and is used to shield the electric field generated by the high-voltage bus;

[0035] The control end of the fuse is connected to the control module in the shielding box, and the execution end of the fuse passes through the ignition hole and is arranged in the fusing area.

[0036] Optionally, the collision information acquisition module includes an acceleration sensor, and the acceleration sensor is configured to acquire linear acceleration information of the vehicle; the control module is further configured to:

[0037] parsing a linear threshold component from the collision threshold, the linear threshold component comprising a first linear threshold component, a second linear threshold component and a third linear threshold component;

[0038] Decomposing the linear acceleration information into a first linear acceleration component, a second linear acceleration component, and a third linear acceleration component;

[0039] If the first linear acceleration component is less than or equal to the first threshold component, and the second linear acceleration component is less than or equal to the second threshold component, and the third linear acceleration component is less than or equal to the third threshold component, marking the vehicle collision information as less than or equal to the collision threshold;

[0040] If the first linear acceleration component is greater than the first threshold component, and / or the second linear acceleration component is greater than the second threshold component, and / or the third linear acceleration component is greater than the third threshold component, the vehicle collision information is marked as greater than the collision threshold.

[0041] Optionally, the collision information collection module further includes a gyroscope; the gyroscope is configured to collect vehicle rollover angular velocity information; and the control module is further configured to:

[0042] Resolving an angle threshold component from the collision threshold;

[0043] Acquiring the flip angular velocity information;

[0044] When executing the step of marking the vehicle collision information as less than or equal to the collision threshold, if the rollover angular velocity information is greater than the angle threshold component, marking the vehicle collision information as greater than the collision threshold;

[0045] If the rollover angular velocity information is less than or equal to the angle threshold component, the vehicle collision information is marked as less than or equal to the collision threshold.

[0046] Optionally, the fusing area is located at an edge of the driving board;

[0047] The dense spot welding assembly includes a target number of welding points, and the target number of welding points form a cantilever structure at the edge of the driving board; the dense spot welding assembly includes a connecting end and a fixed end, and the high-voltage busbar is connected to the connecting end of the dense spot welding assembly;

[0048] The target number is equal to the maximum number of welding points that can disconnect the connecting end and the fixing end under the impact of the acceleration corresponding to the preset collision threshold.

[0049] According to another aspect of the present application, a method for protecting a vehicle electric drive system from collision and power failure is provided, which is applied to the vehicle electric drive system from collision and power failure protection device; the method comprises:

[0050] Obtain vehicle collision information and preset collision threshold;

[0051] If the vehicle collision information is greater than the collision threshold, a start instruction is sent to the fuse, so that the execution end of the fuse generates a melting temperature rise in the melting area to melt the dense spot welding components.

[0052] By means of the above technical scheme, the embodiment of the present application provides a collision power-off protection device and method for a vehicle electric drive system, the device comprising a high-voltage bus, a drive board and a power-off execution unit. The high-voltage bus is connected to the bus port of the drive board through a dense spot welding assembly in the fuse area. The power-off execution unit comprises a control module, a collision information collection module and a fuse. The collision information collection module is connected to the control module and is configured to collect vehicle collision information. One end of the fuse is connected to the control module, and the other end is arranged in the fuse area. The control module can obtain vehicle collision information and a preset collision threshold. If the vehicle collision information is greater than the collision threshold, a start instruction is sent to the fuse so that the execution end of the fuse generates a melting temperature rise in the melting area and melts the dense spot welding assembly. The device can be connected by dense spot welding at the connection between the high-voltage bus and the bus port of the drive board, and the collision information collection module is used to monitor the collision information of the vehicle to judge the collision condition of the vehicle, and then the dense spot welding is melted according to the collision condition, thereby cutting off the electrical connection of the electric drive system to reduce the secondary accident risk of the vehicle after the accident.

[0053] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0055] Figure 1 A schematic diagram of the structure of a collision power-off protection device for a vehicle electric drive system provided in an embodiment of the present application;

[0056] Figure 2 A schematic diagram of a collision detection process provided in an embodiment of the present application;

[0057] Figure 3 A schematic diagram of a fuse control process provided in an embodiment of the present application;

[0058] Figure 4 A schematic diagram of a process of starting a fuse based on linear acceleration and angular velocity provided in an embodiment of the present application;

[0059] Figure 5A schematic diagram of a process for recording vehicle collision information provided in an embodiment of the present application;

[0060] Figure 6 A schematic diagram of a current detection structure provided in an embodiment of the present application;

[0061] Figure 7 A schematic diagram of a temperature detection process provided in an embodiment of the present application;

[0062] Figure 8 A schematic diagram of a fusing process for detecting a blown fuse based on temperature, voltage and current information provided in an embodiment of the present application. DETAILED DESCRIPTION

[0063] The present application will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other without conflict.

[0064] In the embodiment of the present application, the vehicle drive system collision power-off protection device and method can be applied to the electric drive system of an electric vehicle or a hybrid vehicle. The vehicle electric drive system is a system responsible for converting electrical energy into mechanical energy to drive the vehicle to move.

[0065] In some embodiments, the electric drive system may include a motor, a controller and a reducer. Among them, the motor can convert the electrical energy of the power battery into rotational mechanical energy for output power. The controller can control the operating state of the motor according to the instruction set of the vehicle control unit (VCU). The controller can control the working state of the drive motor in real time based on the hardware and software design of power semiconductors. The reducer can adjust the output speed through a transmission mechanism such as a gear set to adapt to different output torques, so that the electric drive system continues to operate in a high-efficiency range.

[0066] The electric drive system may also include a battery, a cooling system, an on-board charger, a high-voltage power distribution unit, a software control unit, and a mechanical structure. Among them, the battery is also called a vehicle power supply, which is used to provide the electrical energy required by the electric drive system. The battery can be a lithium-ion battery, a nickel-metal hydride battery, etc. The cooling system can transfer heat through a coolant circulation loop to keep the key components in the electric drive system working within a suitable temperature range. The on-board charger (OBC) can convert alternating current (AC) into direct current (DC) for charging the battery. The high-voltage power distribution unit (PDU) is responsible for distributing the battery's electrical energy to the electric drive system and other high-voltage electrical equipment. The software control unit includes software applications such as motor control algorithms, fault diagnosis, and energy management, which can automatically control the vehicle's driving process and use process. The mechanical structure may include motor brackets, connectors, etc., which are used to fix and connect the various components of the electric drive system.

[0067] The electric drive system can also divide each device into high-voltage units and low-voltage units according to the working voltage. For example, the voltage architecture of the low-voltage unit is 12V, which is used to provide low-voltage power supply for the vehicle's computer, lighting, sensors and other devices. The voltage architecture of the high-voltage unit can include multiple high-voltage levels in the range of 36V to 900V. The high-voltage levels used in different regions, different models and different standards are also different. For example, for household pure electric vehicles, the voltage architecture can be 375V or 400V. For hybrid vehicles, the voltage range can be 100 to 300V.

[0068] Since the vehicle contains a high-voltage unit, when the vehicle collides, the high-voltage unit may be deformed or displaced due to the impact, causing the high-voltage unit to deviate from the set state. When the high-voltage unit deviates seriously and contacts combustible materials, it may also generate heat or electric sparks due to the high voltage, igniting the combustible materials in contact, causing the vehicle to catch fire and other secondary accident risks after the collision. Therefore, in order to reduce the risk of secondary accidents, in some examples, the vehicle can also be equipped with a collision power-off protection device for the electric drive system.

[0069] The collision power-off protection device can cut off the power supply of the high-voltage unit according to the severity of the collision when the vehicle collides, so that the high-voltage unit no longer generates heat or electric sparks due to the high voltage, thereby reducing the risk of igniting combustible materials. To this end, the collision power-off protection device may include a detector, a controller, and an actuator. Among them, the detector is used to detect relevant information when the vehicle collides, such as acceleration, roll angle, collision force, etc. The controller is used to judge the severity of the collision based on the collision information detected by the detector, and send a control instruction to the actuator when the severity of the collision reaches a preset condition. The actuator can respond to the control instruction sent by the controller, generate a corresponding execution action, and cut off the power supply of the high-voltage unit.

[0070] In some embodiments, the detector may include one or more combinations of an acceleration sensor, an angle sensor, and a strain gauge sensor. The acceleration sensor may be a piezoelectric acceleration sensor, a piezoresistive acceleration sensor, a capacitive acceleration sensor, a servo acceleration sensor, etc. The acceleration during the operation of the vehicle may be converted into an electrical signal, and after pre-processing such as noise reduction and analog-to-digital conversion, the signal may be transmitted to the controller.

[0071] The controller can be a vehicle built-in central processing unit (CPU) or a micro-control unit (MCU) dedicated to the control of the collision power-off protection function. The controller can receive the collision information detected by the detector, judge the collision information, and generate control instructions based on the judgment results and send them to the actuator.

[0072] The actuator can generate corresponding execution actions such as ignition, position movement, deformation, and fracture according to the control instructions sent by the controller to cut off the high-voltage power supply of the high-voltage unit. Depending on the execution action, the execution structure can have different structures. For example, the actuator can include an igniter, an explosive agent, a medicine tube, a fuse, etc. After the controller determines that the collision-related information reaches the preset collision severity, it can generate an ignition signal and send the ignition signal to the igniter. After receiving the ignition signal, the igniter generates an electric spark to detonate the explosive agent in the medicine tube, generating a large amount of gas in a short time. The generated gas forms a high pressure in the cavity of the medicine tube, pushing the fuse to move, thereby cutting off the circuit and cutting off the power to the vehicle.

[0073] For another example, the actuator may be a high-voltage relay, and the controller may generate a disconnection signal according to the collision rollover information and send the disconnection signal to the high-voltage relay. The high-voltage relay cuts off the electrical connection between the power battery module and the vehicle according to the disconnection signal, so that the vehicle is powered off.

[0074] However, the above embodiments have problems such as failure of the power-off protection function under high-voltage conditions and inaccurate judgment of vehicle collision conditions. For example, by relying on the ignition signal to detonate the explosive to push the fuse plate out of contact, when the electrical connection of the circuit is cut off, the degree of collision cannot be judged, the ignition threshold cannot be set according to the degree of collision, and it is difficult to achieve precise control of the collision power-off. In addition, since the fuse plates are close after being cut off, the high voltage will break through the air and continue to supply power. By detecting the vehicle rollover information and using a high-voltage relay to perform circuit breaking, the instantaneous acceleration of the vehicle during a collision cannot be monitored. If the vehicle suddenly collides strongly but does not roll over, the power cannot be cut off in time, so it does not play a protective role.

[0075] In order to alleviate the problem of failure of the power-off protection function, a collision power-off protection device for a vehicle electric drive system is provided in this embodiment. Figure 1 As shown, the device includes: a high-voltage bus 1, a drive board 2 and a power-off execution unit 5.

[0076] Among them, one end of the high-voltage bus 1 can be connected to the vehicle power supply, and the other end can be connected to a specific power-consuming device. Therefore, the high-voltage bus 1 is used to provide an electrical connection path for the components in the high-voltage unit, thereby distributing the high-voltage direct current of the power battery to the power-consuming devices on the vehicle. For electric vehicles, the vehicle power supply is the vehicle power supply battery. The power supply battery can transmit electrical energy with a voltage greater than 36V to the power-consuming devices through the high-voltage bus 1.

[0077] Since the DC function can be used in the vehicle electric drive system, the high-voltage bus 1 can include at least two cables, one of which is used to connect the positive pole of the vehicle power supply, and the other is used to connect the negative pole of the vehicle power supply.

[0078] The high-voltage bus 1 can use a high-voltage cable that meets the preset voltage requirements. The working voltage of the high-voltage cable can be 600AC / 900DC or 1000AC / 1500DC. And it can be in the form of shielded or unshielded single-core and multi-core cables. For example, the cross-sectional area of ​​a single conductor of the multi-core cable conductor in the high-voltage bus 1 is 0.5mm 2 -120mm 2 , the conductor of the multi-core cable can be a stranded copper conductor or a stranded aluminum conductor.

[0079] The drive board 2 is a key part of the electric vehicle power system, responsible for dividing the high-voltage direct current of the power battery into multiple paths to power different electrical devices. For example, the drive board 2 used to drive the motor can be called a motor controller drive board. The motor controller drive board can convert the high-voltage direct current of the power battery into the high-voltage alternating current required by the motor to control the speed and torque of the motor.

[0080] In some embodiments, the driver board 2 may include laminated busbars, filter capacitors, insulated gate bipolar transistors (IGBT), three-phase copper busbars, current sensors, voltage sensors and other components. Taking the motor controller driver board as an example, the driver board 2 can convert direct current into alternating current through power electronic devices such as IGBT to supply the motor. The driver board 2 is also responsible for current sampling to monitor the current state of the motor to ensure that the motor runs in a safe and efficient state.

[0081] The drive board 2 can be connected to the high-voltage bus 1 to obtain power supply from the high-voltage bus 1, that is, one end of the high-voltage bus 1 is connected to the vehicle power supply, and the other end of the high-voltage bus 1 is connected to the drive board 2. In order to connect the high-voltage bus 1, a bus port 3 can also be provided on the drive board 2. The bus port 3 is a key interface for connecting the high-voltage DC power supply and the drive board 2. It is responsible for transmitting the high-voltage DC power provided by the battery pack to the drive board 2, and then supplying power devices such as motors and IGBTs. The bus port 3 can form a wiring assembly through a metal conductor with good conductivity, which is used to transmit power after connecting the high-voltage bus 1.

[0082] The bus port 3 can also be used in conjunction with components such as capacitors to reduce voltage fluctuations and ripples and improve power supply stability. For example, in order to alleviate the problem of electromagnetic interference (EMI), components such as filter capacitors can be provided near the bus port 3 to reduce electromagnetic radiation and improve the electromagnetic compatibility of the system.

[0083] In order to realize the connection between the driving board 2 and the high-voltage busbar 1 and meet the requirements of the collision power-off protection function, the high-voltage busbar 1 is connected to the busbar port 3 through a dense spot welding component 4. Among them, the dense spot welding component 4 is a connection component formed by dense spot welding process. Dense spot welding, also known as multi-spot welding, is a welding technology used in the metal processing industry. It can form a component connection relationship by welding on the driving board 2 through multiple dense welding points.

[0084] In some embodiments, the dense spot welding assembly 4 can form multiple welding points by capacitor discharge (CD) and drawn arc (ARC) spot welding to form a connection assembly. The dense spot welding assembly 4 can be formed by welding metal materials with low melting points such as tin, lead, zinc, and their alloy materials. Therefore, the connection assembly composed of dense spot welding can disconnect the connection between the high-voltage bus 1 and the bus port 3 by heating and melting, so that when the vehicle collides, it can be quickly fused to achieve collision power-off protection.

[0085] The dense spot welding assembly 4 is arranged in the fuse area, and the fuse area is an area demarcated between the high-voltage busbar 1 and the driving board 2 in order to realize the fuse principle. The fuse area can be controlled at the dense spot welding place between the high-voltage busbar 1 and the busbar port 3 (copper busbar) to avoid damage to other components such as filter capacitors. For example, the busbar port 3 is arranged at the edge of the driving board 2, and the ends of the two high-voltage busbars 1 are also located near the edge of the driving board 2. Then, an area covering the two busbar ports and the ends of the two high-voltage busbars 1 can be arranged at the edge of the driving board 2 as the fuse area, and the corresponding dense spot welding assembly 4 is arranged in the demarcated fuse area.

[0086] It should be noted that since the high-voltage busbar 1 and the drive board 2 may be deformed or displaced due to the collision when the vehicle collides, the designated fuse area should have a certain space margin while covering the two busbar ports 3 and the two ends of the high-voltage busbar 1, so that when the vehicle collides, the ends of the high-voltage busbar 1 will not easily contact the surrounding components. The specific space margin can be comprehensively set based on the vehicle's design driving speed, collision test and the layout of the vehicle body parts (especially the high-voltage busbar 1 and the drive board 2).

[0087] In order to meet the design space margin requirements, in some embodiments, when the fuse area is located at the edge of the drive board 2, the dense spot welding assembly 4 can be designed as a cantilever structure located at the edge of the drive board 2. To this end, the dense spot welding assembly 4 may include a plurality of welding points. A plurality of welding points may be evenly arranged and stacked to form a cantilever structure with a certain spatial span. That is, the length of the dense spot welding assembly 4 formed by the plurality of welding points should be greater than or equal to the distance between the bus port and the end of the high-voltage bus 1 to meet the design space margin requirements.

[0088] In some embodiments, the number of welds included in the dense spot welding assembly 4 not only needs to meet the design space margin requirements, but also can achieve the connection relationship between the high-voltage bus 1 and the bus port 3 by disconnecting the welds when a collision occurs. That is, the dense spot welding assembly 4 includes a target number of welds. The target number of welds forms a cantilever structure at the edge of the drive plate 2. The dense spot welding assembly 4 includes a connecting end and a fixed end, and the high-voltage bus 1 is connected to the connecting end of the dense spot welding assembly 4. Among them, the target number is equal to the maximum number of welds that can disconnect the connecting end and the fixed end under the impact of the acceleration corresponding to the preset collision threshold. The collision threshold may include the minimum acceleration that is likely to cause a secondary vehicle collision accident determined by comprehensive indicators such as collision tests, empirical values, and vehicle design requirements.

[0089] For example, the dense spot welding assembly 4 is a rectangular plate structure including N welding spots, one side of the plate-like structure of the dense spot welding assembly 4 is connected to the bus port 3 on the drive board 2 as a fixed end, and the other side of the dense spot welding assembly 4 is connected to the high-voltage bus 1 as a connection end. After the vehicle collides, the high-voltage bus 1 can be relatively displaced with the drive board 2 due to the impact of the acceleration during the collision process. This relative displacement can break the dense spot welding assembly 4, so that the connection between the high-voltage bus 1 and the bus port 3 is cut off. The number of welding spots N included in the dense spot welding assembly 4 can meet the maximum number of welding spots that can be broken when impacted by collision acceleration.

[0090] Obviously, the larger the number N of welds included in the dense spot welding assembly 4, the better the corresponding connection strength, and the smaller the number N of welds included in the dense spot welding assembly 4, the higher the possibility of being broken in the event of a collision. Therefore, by setting N welds, it is possible to meet both the connection strength requirements and the collision disconnection design requirements.

[0091] In order to realize the collision power-off protection function, the collision power-off protection device of the vehicle electric drive system may further include a power-off execution unit 5. The power-off execution unit 5 is used to execute the power-off action, so the power-off execution unit 5 may include a control collision information collection module 51, a control module 52 and a fuse 53. Among them, the collision information collection module 51 is connected to the control module 52. The collision information collection module 51 is configured to collect vehicle collision information and send the collision information to the control module 52.

[0092] In some embodiments, the collision information acquisition module 51 may include an acceleration sensor and / or an angular velocity sensor. The acceleration sensor is used to collect linear acceleration information generated during vehicle travel and collision, which can be used to assist in determining the impact force of a vehicle collision. The angular velocity sensor is used to collect angular velocity and angular acceleration information generated during a collision, which can be used to assist in determining the displacement, flipping, etc. of the vehicle after a collision.

[0093] Similar to the detectors shown in the above embodiments, the acceleration sensor may be one or more combinations of a piezoelectric acceleration sensor, a piezoresistive acceleration sensor, a capacitive acceleration sensor, and a servo acceleration sensor. The angular velocity sensor may be one or more combinations of a gyroscope angular velocity sensor, a Hall angular velocity sensor, a capacitive angular velocity sensor, a piezoelectric angular velocity sensor, a fiber optic gyroscope, an omnidirectional gyroscope, a vibration gyroscope, and a piezoelectric gyroscope.

[0094] The fuse 53 includes a control end and an execution end, the control end of the fuse 53 is connected to the control module 52, and the execution end of the fuse 53 is arranged in the fusing area. The fuse 53 can be controlled by the control module 52 to generate a temperature rise for fusing the dense spot welding assembly 4. The fuse 53 can generate a fusing temperature rise based on electric heating, electric controlled flame, etc.

[0095] For example, the fuse 53 can be an igniter with an electronic control function, and the fuse 53 can include a control unit, a fuel pipe, a fuel valve, an electric spark assembly, etc. Combustible gas or flammable liquid is stored in the fuel pipe, and the fuel valve is arranged on the fuel pipe to control the release and stop of the release of fuel. The control unit can receive the control instruction issued by the control module 52, and control the fuel valve to open in response to the control instruction, so that the fuel is transmitted to the execution end of the fuse 53 located in the fuse area. Then the electric spark assembly is controlled to generate electric sparks to ignite the fuel, and generate a flame for melting the dense spot welding assembly 4. As the temperature near the flame increases, the welding points of the dense spot welding assembly 4 can be melted, and the connection between the high-voltage bus 1 and the bus port 3 can be disconnected, so as to achieve the purpose of power-off protection.

[0096] For another example, when the fuse 53 is an electric heating component, it may include a heating power supply unit, a control unit, a heating wire, and a relay. The heating power supply unit is connected to the heating wire to form a heating circuit. The relay is arranged on the heating circuit to control the circuit on and off of the heating wire. The heating wire is arranged in the fuse area. When the control unit receives the control instruction issued by the control module 52, it can respond to the control instruction and control the closing relay to make the power supply unit supply power to the heating wire to generate a heating current. The thermal effect of the current generates heat at the execution end of the fuse 53 to melt the dense spot welding component 4, disconnect the connection between the high-voltage bus 1 and the bus port 3, and achieve the purpose of power-off protection.

[0097] The control module 52 may be a central controller of the vehicle or a microprocessor dedicated to the power-off protection function. The control module 52 may determine the vehicle collision situation according to the vehicle collision information, and send a control instruction to the fuse 53 according to the collision situation. Figure 2 As shown, the control module 52 can be configured to perform the following steps:

[0098] S101, obtaining vehicle collision information and a preset collision threshold.

[0099] When the vehicle is started or in a parking state, the control module 52 can receive the vehicle collision information collected by the collision information collection module 51. Depending on the type of sensor included in the collision information collection module 51, the vehicle collision information collected by the collision information collection module 51 can include different types. For example, when the collision information collection module 51 includes an acceleration sensor, the collected vehicle collision information may include linear acceleration information. When the collision information collection module 51 includes an angular velocity sensor, the collected vehicle collision information may include angular velocity information.

[0100] Before or at the same time as receiving the vehicle collision information, the control module 52 may also obtain a preset collision threshold. The collision threshold is one or more thresholds related to the collision information used to determine the severity of the collision. For example, the greater the linear acceleration of the vehicle, the greater the force applied to the vehicle, and the more likely it is caused by a vehicle collision. Therefore, by setting the linear acceleration threshold, when it is determined that the vehicle acceleration exceeds the preset collision threshold, it indicates that the vehicle may be subjected to a more serious collision and requires collision power-off protection.

[0101] In order to determine the severity of a vehicle collision, a collision threshold may be set based on one or more combinations of empirical values, vehicle collision tests, vehicle design standards, and vehicle usage data. The collision threshold may be set based on vehicle usage data, and the collision threshold may be dynamically variable, that is, the collision threshold may be set based on acceleration information during vehicle operation. Therefore, the collision threshold is a threshold set based on historical acceleration information within a preset judgment period.

[0102] In some embodiments, the control module 52 is further configured to obtain historical acceleration information within the preset judgment period and set the collision threshold according to the historical acceleration information when executing the step of obtaining the preset collision threshold. The historical acceleration information may be acceleration information recorded during the operation of the vehicle according to the preset sampling frequency. For example, if the preset judgment period is 24 hours and the preset sampling period is 1 minute, then during the driving of the vehicle, sampling may be performed every 1 minute to save the acceleration information detected by the collision information acquisition module 51 when the vehicle is driving, i.e., the historical acceleration information. When obtaining the preset collision threshold, the control module 52 may obtain all acceleration information recorded within 24 hours.

[0103] Then, the average acceleration value is calculated based on the acquired acceleration information, and the acceleration range is determined based on the acceleration average value, and the collision threshold is determined based on the mapping relationship between the acceleration range and the collision threshold. For example, the historical acceleration information acquired by the vehicle includes a1, a2, ..., a n , then the average acceleration can be calculated based on the historical acceleration information, that is, a = (a1 + a2 + ... + an ) / n. Then determine the acceleration range based on the average acceleration value, that is, a is between [a m , a m+1 ] interval, thus determining [a m , a m+1] The collision threshold a corresponding to the interval t .

[0104] When the vehicle is traveling in an environment with complex road conditions such as congestion or mountain roads, it will be affected by factors such as driving behavior (such as braking, frequent acceleration and deceleration, etc.), traffic conditions, and road bumps. The acceleration collected by the collision information collection module 51 is greater than the acceleration of the vehicle traveling on an uncongested, flat road. Therefore, the vehicle's recent driving road environment can be judged through historical acceleration information, and a dynamic collision threshold can be set to reduce the impact of changes in acceleration information caused by the driving environment on the collision state detection process, thereby reducing the probability of misjudging a collision and causing power failure.

[0105] S102: If the vehicle collision information is greater than the collision threshold, a start instruction is sent to the fuse, so that the execution end of the fuse generates a melting temperature rise in the melting area to melt the dense spot welding assembly.

[0106] After obtaining the vehicle collision information and the preset collision threshold, the control module 52 can compare the obtained vehicle collision information with the preset collision threshold. If the vehicle collision information is greater than the collision threshold, it means that the current vehicle collision information is abnormal, and it can be determined that a collision has occurred, so a start instruction can be sent to the fuse 53.

[0107] After receiving the start command, the fuse 53 can respond to the start command and start the ignition or electric heating function, thereby generating a melting temperature rise at the execution end of the fuse 53. Since the execution end of the fuse 53 is located in the melting area, the generated melting temperature rise can act on the dense spot welding assembly 4, thereby melting the dense spot welding assembly 4, cutting off the connection between the high-voltage bus 1 and the bus port 3, and stopping the power supply to the drive board 2, thereby reducing the risk of secondary accidents.

[0108] In some embodiments, when the collision information collection module 51 includes an acceleration sensor, the acceleration sensor is configured to collect linear acceleration information of the vehicle. Figure 3 , Figure 4 As shown, after obtaining the vehicle collision information and the preset collision threshold, the control module 52 can also parse the linear threshold component from the collision threshold. The linear threshold component includes a first linear threshold component, a second linear threshold component and a third linear threshold component. The first linear threshold component, the second linear threshold component and the third linear threshold component are threshold components on three mutually perpendicular coordinate axes.

[0109] For example, according to the coordinate axis setting method of the Cartesian coordinate system, the first linear threshold component is the threshold component of the linear acceleration threshold in the collision threshold on the x-axis. The second linear threshold component is the threshold component of the linear acceleration threshold in the collision threshold on the y-axis. The third linear threshold component is the threshold component of the linear acceleration threshold in the collision threshold on the z-axis. In order to facilitate threshold judgment, the linear acceleration threshold in the collision threshold can directly set three threshold components, namely, the first linear threshold component in the x-axis direction, the second linear threshold component in the y-axis direction, and the third linear threshold component in the z-axis direction.

[0110] The linear acceleration information is then decomposed into a first linear acceleration component, a second linear acceleration component, and a third linear acceleration component. Corresponding to the first linear threshold component, the second linear threshold component, and the third linear threshold component, the linear acceleration information can also be decomposed into a first linear acceleration component, a second linear acceleration component, and a third linear acceleration component based on three mutually perpendicular direction coordinate axes, that is:

[0111] After the linear threshold component is obtained by analysis and the linear acceleration component is decomposed, the linear acceleration component in each direction can be compared with the linear threshold component respectively. When the linear acceleration components in all directions are less than or equal to the linear threshold component, it is determined that the vehicle collision information is less than or equal to the collision threshold. That is, through comparison, if the first linear acceleration component is less than or equal to the first threshold component, and the second linear acceleration component is less than or equal to the second threshold component, and the third linear acceleration component is less than or equal to the third threshold component, it is marked that the vehicle collision information is less than or equal to the collision threshold.

[0112] Correspondingly, if the linear acceleration component in any direction is greater than the linear threshold component, it is determined that the vehicle collision information is greater than the collision threshold. That is, if the first linear acceleration component is greater than the first threshold component, and / or the second linear acceleration component is greater than the second threshold component, and / or the third linear acceleration component is greater than the third threshold component, it is marked that the vehicle collision information is greater than the collision threshold.

[0113] In some embodiments, when the collision information acquisition module 51 includes a gyroscope, the gyroscope may be configured to acquire vehicle rollover angular velocity information. Then the control module 52 may parse the angle threshold component from the collision threshold and acquire the rollover angular velocity information.

[0114] The flip angular velocity information is then compared with the angle threshold component, and when the flip angular velocity information is greater than the angle threshold component, it is determined that the vehicle collision information is greater than the collision threshold. Similarly, when the flip angular velocity information is less than or equal to the angle threshold component, it can be determined that the vehicle collision information is less than or equal to the collision threshold.

[0115] In some embodiments, when the collision information acquisition module 51 includes a linear acceleration sensor and a gyroscope, the linear acceleration component in each direction can be compared with the linear threshold component, and the flip angular velocity information can be compared with the angle threshold component. When the linear acceleration components in all directions are less than or equal to the linear threshold component, and the flip angular velocity information is less than or equal to the angle threshold component, it is determined that the vehicle collision information is less than or equal to the collision threshold.

[0116] That is, if the first linear acceleration component is less than or equal to the first threshold component, and the second linear acceleration component is less than or equal to the second threshold component, and the third linear acceleration component is less than or equal to the third threshold component, then when executing the step of marking the vehicle collision information as less than or equal to the collision threshold, it is also necessary to compare the flip angular velocity information with the angle threshold component, and if the flip angular velocity information is less than or equal to the angle threshold component, mark the vehicle collision information as less than or equal to the collision threshold. If the flip angular velocity information is greater than the angle threshold component, mark the vehicle collision information as greater than the collision threshold.

[0117] It can be seen that when implementing the collision power-off protection function, the acceleration sensor and the gyroscope can work together to make a comprehensive judgment on the vehicle collision process. The gyroscope can detect the angular velocity of the vehicle when it flips, and the acceleration sensor can detect the linear acceleration in the x-axis, y-axis, and z-axis directions of the vehicle at the moment of collision. By performing attitude calculation on the measurement data of the gyroscope and the acceleration sensor, the attitude information of the carrier can be obtained. When the linear acceleration a1 is greater than the preset linear acceleration threshold a t , or the angular velocity ω1 is greater than the preset angular velocity threshold ω t , the collected information is output to the control module 52, and the fuse 53 is controlled to generate a melting temperature rise.

[0118] In some embodiments, the bus port 3 and the high-voltage bus 1 can reserve a certain stress through the position relationship when connected. The reserved stress can separate the bus port and the high-voltage bus 1 by a certain safety distance after the dense spot welding assembly 4 is melted, reduce the possibility that the high-voltage bus 1 still contacts the bus port after the dense spot welding assembly 4 is melted, and improve safety.

[0119] S103: If the vehicle collision information is less than or equal to the collision threshold, record the vehicle collision information to set a collision threshold in a next judgment cycle.

[0120] like Figure 5 As shown, in some embodiments, by comparing the vehicle collision information and the preset collision threshold, if the vehicle collision information is less than or equal to the collision threshold, it means that the current vehicle has not collided, or the collision is relatively light and is not likely to cause a secondary accident. Therefore, the vehicle collision information can be recorded, that is, the acquired acceleration information is stored as historical acceleration information to set the collision threshold in the next judgment cycle.

[0121] It can be seen that based on the collision power-off protection device for the vehicle electric drive system shown in the above embodiment, a dense spot welding assembly 4 is set at the connection between the high-voltage bus 1 and the bus port 3 (copper busbar). When the vehicle collides, the acceleration sensor and the gyroscope collect linear acceleration information and angular velocity (or angular acceleration) information to judge the instantaneous acceleration and flip angular velocity information of the vehicle collision. When the collected data is greater than the threshold value of the collision judgment, the control module 52 starts the fuse 53 to melt the welding point, thereby cutting off the electrical connection between the copper busbar and the high-voltage bus 1, and realizing the function of collision power-off protection.

[0122] Further, as a refinement and expansion of the specific implementation of the above embodiment, in order to fully illustrate the specific implementation process of this embodiment, some embodiments of this application also provide a collision power-off protection device for a vehicle electric drive system, such as Figure 6 As shown, the device also includes an electric energy sensor. The electric energy sensor can be arranged on the high-voltage bus 1 and / or the fuse area and / or the drive board 2, and connected to the control module 52. Therefore, the electric energy sensor is configured to collect power-on information of the high-voltage bus 1 and / or the drive board 2, and send the power-on information to the control module 52. Among them, the power-on information is information used to characterize whether there is an electrical connection between the drive board 2 and the high-voltage bus 1. For example, the power-on information can be current, voltage and a combination thereof.

[0123] Correspondingly, such as Figure 7 As shown, the control module 52 is also configured to:

[0124] S201, receiving the power-on information.

[0125] Depending on the type of the electric energy sensor, the content of the power-on information received by the control module 52 is also different. For example, when the electric energy sensor is an ammeter connected in series to the high-voltage bus 1, the power-on information received by the control module 52 is the current value. For another example, when the electric energy sensor is a voltmeter connected in parallel to both ends of the dense spot welding assembly 4, the power-on information received by the control module 52 is the voltage value.

[0126] S202: If the power-on information indicates that the power supply has been cut off, a stop instruction is sent to the fuse 53 to control the execution end of the fuse 53 to stop generating a fusing temperature rise in the fusing area.

[0127] After receiving the power-on information, the control module 52 can judge the power-on information to determine whether the power supply corresponding to the high-voltage bus 1 has been cut off. Depending on the specific content of the power-on information, the basis for the control module 52 to judge whether the power supply corresponding to the high-voltage bus 1 has been cut off is also different. For example, when the power-on information is a current value, if the current value is equal to 0, it means that the power supply corresponding to the high-voltage bus 1 has been cut off. If the current value is not equal to 0, it means that the power supply corresponding to the high-voltage bus 1 has not been cut off. For another example, when the power-on information is a voltage value, if the voltage value at both ends of the dense spot welding assembly 4 is 0, it means that the power supply corresponding to the high-voltage bus 1 has not been cut off. If the voltage value at both ends of the dense spot welding assembly 4 is not 0, it means that the power supply corresponding to the high-voltage bus 1 has been cut off.

[0128] When the power-on information indicates that the power supply corresponding to the high-voltage bus 1 has been cut off, the control module 52 can send a stop command to the fuse 53. After receiving the stop command, the fuse 53 can respond to the stop command and stop generating the melting temperature rise. That is, the control module 52 can monitor the voltage and current information on the high-voltage bus 1 or the drive board 2 in real time, and judge whether the dense spot welding assembly 4 is fused according to the voltage and current information. When the dense spot welding assembly 4 is fused, the control module 52 can control the ignition module to turn off according to the feedback voltage and current information, thereby realizing the vehicle collision power-off protection function.

[0129] S203: If the power-on information indicates that the power supply is not cut off, a continuous temperature rise instruction is sent to the fuse 53 to control the execution end of the fuse 53 to continuously generate a fusing temperature rise in the fusing area.

[0130] When the power-on information indicates that the power supply corresponding to the high-voltage bus 1 has not been cut off, it means that the fuse function has not been completed. Therefore, the power-on information can be continuously monitored until the power-on information is detected to indicate that the power supply corresponding to the high-voltage bus 1 has been cut off.

[0131] In order to timely implement the collision power-off protection function, if the power-on information indicates that the power supply corresponding to the high-voltage bus 1 is not cut off, the control module 52 can also send a continuous temperature rise instruction to the fuse 53. The continuous temperature rise instruction can have different control modes according to the type of the fuse 53. For example, when the fuse 53 is an igniter, the continuous temperature rise instruction can control the igniter to increase the fuel release flow rate to increase the flame and melt the dense spot welding assembly 4. When the fuse 53 is an electric heater, the continuous temperature rise instruction can also be used to control the electric heater to increase the power supply and increase the heating value of the heating wire.

[0132] like Figure 8 As shown, in some embodiments, when the vehicle electric drive system collision power-off protection device implements the fusing, it can also monitor the temperature of the fusing area, that is, the device also includes a temperature sensor arranged in the fusing area. The temperature sensor can be a thermocouple, a thermistor, an infrared temperature sensor, etc. The temperature sensor is connected to the control module 52, and the temperature sensor is configured to collect temperature information in the fusing area and send the temperature information to the control module 52.

[0133] Correspondingly, the control module 52 is further configured to: obtain the temperature information and a preset temperature threshold, and compare the temperature information with the preset temperature threshold, and if the temperature information is greater than or equal to the temperature threshold, execute the step of receiving the power-on information.

[0134] For example, the device can also monitor the temperature of the dense spot welding assembly 4 through a temperature sensor. When it is detected that the temperature has not reached the melting point of the welding point, the control module 52 can control the melting temperature of the fuse 53 to continue to rise until the temperature reaches the melting point of the welding point and stops rising. At the same time, the voltage and current information on the high-voltage bus 1 is monitored in real time through the power sensor. Whether the dense spot welding assembly 4 is fused is determined by the voltage and current information. When it is detected that the dense spot welding assembly 4 is fused, the fuse 53 can be controlled to close according to the feedback voltage and current information, thereby realizing the function of vehicle power-off protection.

[0135] If the temperature information is less than the temperature threshold, the temperature information in the fusing area can be continuously monitored. In some embodiments, when it is determined that the temperature information is less than the temperature threshold, the temperature rise in a unit time can be calculated. The temperature rise is compared with a preset rise threshold. If the temperature rise is less than the preset rise threshold, a restart instruction is sent to the fuse 53 to control the fuse 53 to generate a fusing temperature rise in the fusing area, thereby fusing the dense spot welding assembly 4.

[0136] That is, the control module 52 can determine whether the fuse 53 is working normally according to the temperature increase. When the temperature increase is less than the preset increase threshold, it means that the temperature increase is small, and the fuse 53's melting temperature rise output is abnormal. Therefore, a restart instruction can be sent to the fuse 53 to re-control the fuse 53 to melt. If the temperature increase is greater than or equal to the preset increase threshold, the voltage and current information on the high-voltage bus 1 can be monitored in real time through the power sensor in the manner provided in the above embodiment, that is, the step of receiving the power-on information is performed.

[0137] Since the high-voltage bus 1 and other electrical components of the vehicle will form an electric field and a magnetic field in the surrounding environment after being energized, and the power-off execution unit 5 is in a weak current environment and is easily interfered by the electromagnetic field in the surrounding environment, therefore, in some embodiments, in order to prevent the ignition module from being interfered by the electromagnetic interference in the surrounding electromagnetic environment when working, the device also includes a shielding box 6, and the control module 52 is arranged in the shielding box 6. Among them, the shielding box 6 includes a metal shielding layer and a through hole, and the metal shielding layer is arranged on the periphery of the control module 52 to shield the electric field generated by the high-voltage bus 1. The control end of the fuse 53 is connected to the control module 52 in the shielding box 6, and the execution end of the fuse 53 is arranged in the fuse area through the through hole.

[0138] For example, the shielding box 6 is a rectangular box of metal material, and the control module 52 and the electronic components for signal processing can be arranged in the shielding box 6. The fuse 53 can be a cylindrical structure, one end of which is arranged in the shielding box 6 as a control end and is connected to the control module 52. The shielding box 6 is provided with two through holes with a diameter slightly larger than the diameter of the cylinder of the fuse 53. The cylinder of the fuse 53 passes through the two through holes from the shielding box 6 and extends to the outside of the shielding box 6, enters the fusing area to form an execution end. By placing the control module 52 in the shielding box 6, it is possible to shield the control module 52 and each connected signal line, thereby ensuring that the ignition module can work normally when the vehicle collides.

[0139] Further, as a method for implementing the vehicle electric drive system collision power-off protection device described in the above embodiment, the embodiment of the present application also provides a vehicle electric drive system collision power-off protection method, which is applied to the vehicle electric drive system collision power-off protection device; the method includes:

[0140] Obtain vehicle collision information and preset collision threshold;

[0141] If the vehicle collision information is greater than the collision threshold, a start instruction is sent to the fuse, so that the execution end of the fuse generates a melting temperature rise in the melting area to melt the dense spot welding components.

[0142] By applying the technical solution of this embodiment, the embodiment of the present application provides a vehicle electric drive system collision power-off protection device and method. The method can use the collision information acquisition module to monitor the vehicle's acceleration information to determine the vehicle collision condition, and fuse the dense spot welding points according to the collision condition, thereby cutting off the electrical connection of the electric drive system to reduce the risk of secondary accidents of the vehicle after the accident.

[0143] It should be noted that for other corresponding descriptions of the various steps involved in the vehicle electric drive system collision power-off protection method provided in an embodiment of the present application, reference can be made to the corresponding descriptions in the vehicle electric drive system collision power-off protection device provided in the above embodiment, and will not be repeated here.

[0144] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0145] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A collision power-off protection device for a vehicle electric drive system, characterized in that: The device comprises: High-voltage busbar, connected to vehicle power supply; The driving board comprises a busbar port, wherein the high-voltage busbar is connected to the busbar port via a dense spot welding assembly; the dense spot welding assembly is arranged in a fuse area; A power-off execution unit, comprising a control module, a collision information acquisition module and a fuse; the collision information acquisition module is connected to the control module; the fuse comprises a control end and an execution end, the control end of the fuse is connected to the control module, and the execution end of the fuse is arranged in the fuse region; The collision information collection module is configured to collect vehicle collision information and send the collision information to the control module; The control module is configured to: Obtain vehicle collision information and preset collision threshold; If the vehicle collision information is greater than the collision threshold, a start instruction is sent to the fuse, so that the execution end of the fuse generates a melting temperature rise in the melting area to melt the dense spot welding component.

2. The device according to claim 1, characterized in that The device also includes: An electric energy sensor is connected to the control module; the electric energy sensor is configured to collect power-on information of the high-voltage bus and / or the drive board, and send the power-on information to the control module; the control module is further configured to: receiving the power-on information; If the power-on information indicates that the power supply has been cut off, a stop instruction is sent to the fuse to control the execution end of the fuse to stop generating a fusing temperature rise in the fusing area; If the power-on information indicates that the power supply is not cut off, a continuous temperature rise instruction is sent to the fuse to control the execution end of the fuse to continuously generate a fusing temperature rise in the fusing area.

3. The device according to claim 2, characterized in that The device also includes: a temperature sensor, arranged in the fuse area; the temperature sensor is connected to the control module, the temperature sensor is configured to collect temperature information in the fuse area, and send the temperature information to the control module; the control module is further configured to: Acquiring the temperature information and a preset temperature threshold; If the temperature information is greater than or equal to the temperature threshold, performing the step of receiving the power-on information; If the temperature information is less than the temperature threshold, the temperature information in the fuse area is continuously monitored.

4. The device according to claim 3, characterized in that If the temperature information is less than the temperature threshold, the control module is further configured to: Calculate the temperature rise per unit time; If the temperature rise is less than a preset rise threshold, a re-start instruction is sent to the fuse to control the fuse to generate a melting temperature rise in the melting area to melt the dense spot welding assembly; If the temperature increase is greater than or equal to the preset increase threshold, the step of receiving the power-on information is performed.

5. The device according to claim 1, characterized in that The vehicle collision information includes acceleration information, and the control module is further configured to: Obtaining historical acceleration information within the preset judgment period; Setting the collision threshold according to the historical acceleration information; If the vehicle collision information is less than or equal to the collision threshold, the acceleration information in the vehicle collision information is recorded to set the collision threshold in the next judgment cycle.

6. The device according to claim 1, characterized in that The device also includes: A shielding box, wherein the control module is arranged in the shielding box; The shielding box comprises a metal shielding layer and a through hole, wherein the metal shielding layer is arranged at the periphery of the control module and is used to shield the electric field generated by the high-voltage bus; The control end of the fuse is connected to the control module in the shielding box, and the execution end of the fuse passes through the ignition hole and is arranged in the fusing area.

7. The device according to claim 1, characterized in that The collision information acquisition module includes an acceleration sensor, and the acceleration sensor is configured to acquire linear acceleration information of the vehicle; the control module is further configured to: parsing a linear threshold component from the collision threshold, the linear threshold component comprising a first linear threshold component, a second linear threshold component and a third linear threshold component; Decomposing the linear acceleration information into a first linear acceleration component, a second linear acceleration component, and a third linear acceleration component; If the first linear acceleration component is less than or equal to the first threshold component, and the second linear acceleration component is less than or equal to the second threshold component, and the third linear acceleration component is less than or equal to the third threshold component, marking the vehicle collision information as less than or equal to the collision threshold; If the first linear acceleration component is greater than the first threshold component, and / or the second linear acceleration component is greater than the second threshold component, and / or the third linear acceleration component is greater than the third threshold component, the vehicle collision information is marked as greater than the collision threshold.

8. The device according to claim 7, characterized in that The collision information acquisition module further includes a gyroscope; the gyroscope is configured to acquire vehicle rollover angular velocity information; the control module is further configured to: Resolving an angle threshold component from the collision threshold; Acquiring the flip angular velocity information; When executing the step of marking the vehicle collision information as less than or equal to the collision threshold, if the rollover angular velocity information is greater than the angle threshold component, marking the vehicle collision information as greater than the collision threshold; If the rollover angular velocity information is less than or equal to the angle threshold component, the vehicle collision information is marked as less than or equal to the collision threshold.

9. The device according to claim 1, characterized in that The fusing area is located at the edge of the driving board; The dense spot welding assembly includes a target number of welding points, and the target number of welding points form a cantilever structure at the edge of the driving board; the dense spot welding assembly includes a connecting end and a fixed end, and the high-voltage busbar is connected to the connecting end of the dense spot welding assembly; The target number is equal to the maximum number of welding points that can disconnect the connecting end and the fixing end under the impact of the acceleration corresponding to the preset collision threshold.

10. A collision power-off protection method for a vehicle electric drive system, characterized in that: The vehicle electric drive system collision power-off protection device applied to any one of claims 1 to 9; the method comprises: Obtain vehicle collision information and preset collision threshold; If the vehicle collision information is greater than the collision threshold, a start instruction is sent to the fuse, so that the execution end of the fuse generates a melting temperature rise in the melting area to melt the dense spot welding components.

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