A vehicle door emergency control method and system based on thermoelectric conversion

Abstract

The application relates to a kind of vehicle door emergency control method and system based on thermoelectric conversion, and the method comprises: using the flexible thermoelectric material array laid between the floor and battery pack in vehicle, real-time acquisition floor temperature change, and based on Seebeck effect, floor heat is converted into thermoelectric power difference;Based on the amplitude of thermoelectric power difference, in combination with the output voltage polarity and temperature space distribution characteristics of flexible thermoelectric material array, the overheating abnormal information of battery pack is obtained;In the case of vehicle electric control system power failure, according to the overheating abnormal information, the vehicle door is controlled to execute self-driven unlocking mode through hierarchical response, and the self-driven unlocking mode comprises: electromagnetic self-driven mode driven by thermoelectric power difference, and thermal mechanical drive mode generated by deformation tension of floor heat conduction shape memory alloy element.The application can automatically and reliably open the vehicle door lock in the extreme case of electronic door lock failure.

Description

Technical Field

[0001] This invention relates to the field of vehicle door emergency control technology, and in particular to a vehicle door emergency control method and system based on thermoelectric conversion. Background Technology

[0002] With the rapid development of electric vehicles, vehicle safety has become an increasingly important concern. Among these concerns, battery pack thermal runaway is one of the major challenges facing the industry. When abnormal conditions such as short circuits or overcharging occur inside the battery pack, a chain reaction of exothermic reactions can be triggered, causing the battery temperature to rise sharply and potentially even catch fire. In such extreme situations, the vehicle's electrical system can easily fail completely within a short period due to high temperatures, short circuits, or burnt-out cables.

[0003] Currently, electric vehicle door lock control systems typically rely on the vehicle's low-voltage electrical network. Furthermore, to address emergencies such as collisions, some vehicles are equipped with automatic unlocking functions. For example, after the airbag controller detects a collision signal, it sends an unlocking command to the body controller via the controller area network bus, which then drives the door lock motor to unlock. However, door lock control schemes relying on electrical signals and controller logic have significant drawbacks in battery thermal runaway scenarios: thermal runaway is often accompanied by severe temperature rises and flames. The vehicle's low-voltage wiring harness, controller circuit board, and door lock motor itself are highly susceptible to damage or burnout from high temperatures within a short period. Once the electrical signal link is interrupted, regardless of the preset collision unlocking logic, the door lock actuator cannot obtain effective driving power or control commands, thus preventing the door from being opened from the inside.

[0004] Several improvement solutions have been proposed in existing technologies. For example, some solutions attempt to add a mechanical cable or physical handle inside the door, directly connecting it to the door lock lever to achieve purely mechanical emergency unlocking. While this solution provides a physical unlocking method in case of electrical failure, its triggering relies entirely on the occupant's active operation. If the occupant cannot find or pull the mechanical handle in time, it can lead to escape delays. Another approach is to add a backup power supply to the vehicle's low-voltage side to temporarily maintain power to the door lock motor in case of main power failure. However, this solution still depends on the normal operation of the electronic control logic and the door lock motor, and the backup power supply itself is also at risk of failure in high-temperature environments, failing to fundamentally solve the link dependency problem.

[0005] Therefore, how to reliably and automatically unlock the vehicle doors without relying on the onboard electronic control system or the active operation of the occupants under extreme conditions where battery thermal runaway leads to the complete failure of the vehicle's electrical system is an urgent technical problem to be solved in this field. Summary of the Invention

[0006] (a) Technical problems to be solved

[0007] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a vehicle door emergency control method and system based on thermoelectric conversion, which solves the technical problem of how to automatically and reliably open the vehicle door lock when the vehicle's electrical system fails completely due to battery thermal runaway and the occupants are unable to actively operate the mechanical handle.

[0008] (II) Technical Solution

[0009] To achieve the above objectives, the main technical solutions adopted by the present invention include:

[0010] In a first aspect, embodiments of the present invention provide a vehicle door emergency control method based on thermoelectric conversion, comprising:

[0011] By using a flexible thermoelectric material array laid between the vehicle floor and the battery pack, the floor temperature change is collected in real time, and the floor heat is converted into thermoelectric electromotive force based on the Seebeck effect.

[0012] Based on the amplitude of the thermoelectric potential, combined with the output voltage polarity and temperature spatial distribution characteristics of the flexible thermoelectric material array, the overheating anomaly information of the battery pack is obtained.

[0013] In the event of a power failure in the vehicle's electronic control system, based on overheating anomaly information, the door is controlled to execute a self-driven unlocking mode through a graded response. The self-driven unlocking modes include: an electromagnetic self-driven mode in which the thermoelectric electromotive force is transmitted to the electromagnetic engagement mechanism in the door lock actuator to drive the door lock mechanical unloading; and a thermomechanical drive mode in which the heat collected from the flexible thermoelectric material array is transferred to the shape memory alloy element in the door lock actuator through a heat conduction path to generate mechanical pulling force to open the door lock through phase change contraction.

[0014] Optionally, based on the amplitude of the thermoelectric potential, combined with the output voltage polarity and temperature spatial distribution characteristics of the flexible thermoelectric material array, the overheating anomaly information of the battery pack can be obtained, including:

[0015] By calibrating the historical temperature rise curves under two operating conditions—normal vehicle operation and thermal runaway—the thermal runaway threshold of the battery can be obtained.

[0016] When the amplitude of the thermoelectric potential exceeds the thermal runaway threshold and the floor temperature exceeds the preset second temperature threshold, the battery pack is judged to be in an overheating abnormality and a thermal runaway state.

[0017] In the thermal runaway state, based on the output voltage polarity and temperature spatial distribution characteristics of the flexible thermoelectric material array, the thermal runaway region of the battery is located, and the local overheating region of the battery pack is obtained.

[0018] Based on the information on the local overheated areas and the location distribution of occupants inside the vehicle, an emergency opening priority for the doors is generated. The information on the location distribution of occupants inside the vehicle includes the presence status and location of occupants in each seat.

[0019] Optionally, based on the output voltage polarity and temperature spatial distribution characteristics of the flexible thermoelectric material array, the thermal runaway region of the battery is located, and the local overheating region of the battery pack is obtained, including:

[0020] The output voltage polarity of each unit in the flexible thermoelectric material array is obtained, and the output voltage polarity is analyzed in the heat source space to obtain the heat source transfer direction.

[0021] When the heat source transfers upward from the floor, the spatial distribution field of the temperature gradient of the flexible thermoelectric material array is obtained.

[0022] If a local peak feature exists in the spatial distribution field of the temperature gradient, then the location corresponding to the local peak feature is determined to be a local overheating region of the battery pack.

[0023] Optionally, based on the distribution information of the localized overheated area and the location of the occupants, the emergency opening priority of the doors can be generated, including:

[0024] Obtain the presence status and position of each member in the vehicle, and determine the associated seat set corresponding to each door;

[0025] Based on the thermal radiation distance between each door and the local overheated area, and combined with the number of members in the set of seats associated with that door, the emergency avoidance coefficient of each door is determined.

[0026] The emergency opening priority of the car doors is generated in descending order of emergency avoidance coefficient.

[0027] Among them, the emergency avoidance coefficient is inversely proportional to the distance of thermal radiation, and directly proportional to the number of members present.

[0028] Optionally, based on the overheating anomaly information, controlling the door to execute a self-driven unlocking mode through a graded response includes:

[0029] When the overheating anomaly is in a high temperature warning state and the floor temperature is higher than the preset first temperature threshold, an audible and visual alarm signal is sent to the preset alarm unit, and the floor temperature data is uploaded to the cloud.

[0030] When the overheating anomaly is in a state of thermal runaway and the floor temperature is higher than the preset second temperature threshold, the door is controlled to execute the electromagnetic self-drive mode, which uses the thermoelectric potential to drive the door lock to mechanically unload.

[0031] In electromagnetic self-drive mode and when the door is not detected to be open, the door is controlled to execute thermomechanical drive mode, so that the heat collected from the flexible thermoelectric material array is transferred to the shape memory alloy element in the door lock actuator through the heat conduction path, and the mechanical pulling force is generated by phase change contraction to open the door lock.

[0032] Secondly, embodiments of the present invention provide a vehicle door emergency control system based on thermoelectric conversion, used to implement the above-described vehicle door emergency control method based on thermoelectric conversion, the system comprising:

[0033] A flexible thermoelectric floor array is laid between the vehicle floor and the battery pack to collect floor temperature changes in real time and convert thermal energy into electrical energy.

[0034] The heat transfer bus is connected to the flexible thermoelectric floor array and the door lock actuator respectively, and is used to transfer the thermal energy or electrical energy of the flexible thermoelectric floor array to the door lock actuator.

[0035] The door lock actuator, integrated into the door lock body, includes an electromagnetic engagement mechanism and a shape memory alloy element. The electromagnetic engagement mechanism is used to receive the thermoelectric electromotive force and directly drive the door lock to mechanically unload. The shape memory alloy element undergoes phase change and contraction under the action of heat conduction through the heat transfer bus to generate mechanical unlocking force.

[0036] Optionally, the flexible thermoelectric floor array uses a Bi2Te3-based composite thermoelectric thin film material;

[0037] Each thermoelectric unit in the flexible thermoelectric floor array has its hot end facing the vehicle floor surface and its cold end facing the bottom of the vehicle body. Multiple thermoelectric units are arranged in a spatial grid to form a topology that corresponds to the cell layout inside the battery pack.

[0038] Optionally, the heat transfer bus is a composite structure of optical fiber and metal heat-conducting bus;

[0039] Optical fiber is used to transmit temperature signals;

[0040] Metal thermally conductive busbars are used to transfer electrical energy to the electromagnetic engagement mechanism in the door lock actuator and to transfer thermal energy to the shape memory alloy elements in the door lock actuator.

[0041] Optionally, the door lock actuator is also provided with a heat collection chamber, which is connected to a flexible thermoelectric floor array through a thermally conductive material to temporarily store heat and maintain the phase change time window of the shape memory alloy element.

[0042] Optionally, the emergency control system interacts with the vehicle's low-voltage bus and onboard controller without electrical signals, operating by utilizing the thermal energy and thermoelectric potential generated under battery pack thermal runaway conditions.

[0043] (III) Beneficial Effects

[0044] The beneficial effects of this invention are as follows: The emergency door control method based on thermoelectric conversion of this invention utilizes a flexible thermoelectric material array laid between the vehicle floor and the battery pack to collect temperature in real time and convert it into a thermoelectric electromotive force based on the Seebeck effect. Simultaneously, it accurately obtains battery pack overheating anomaly information based on the amplitude, polarity, and spatial temperature distribution characteristics of the thermoelectric electromotive force. This allows for a graded response to the anomaly information in the event of a power failure in the vehicle's electronic control system, employing either an electromagnetic self-drive mode or a thermomechanical drive mode for automatic door unlocking. Compared to existing technologies, this method can automatically unlock the door even in the event of a complete failure of the vehicle's electrical system, no backup power supply, and no active operation by the occupants, by simultaneously providing both electrical and thermal energy—two independent physical driving sources—using only the heat generated by the battery's thermal runaway. Attached Figure Description

[0045] Figure 1 This is a flowchart illustrating an emergency door control method based on thermoelectric conversion, provided in an embodiment of the present invention.

[0046] Figure 2 This is a flowchart of a sub-step in step S200 of a vehicle door emergency control method provided in an embodiment of the present invention;

[0047] Figure 3 This is a flowchart of a sub-step in step S300 of the emergency door control method provided in an embodiment of the present invention. Detailed Implementation

[0048] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0049] refer to Figures 1 to 3 As shown in the embodiment of the present invention, an emergency control method for vehicle doors based on thermoelectric conversion includes: using a flexible thermoelectric material array laid between the vehicle floor and the battery pack to collect floor temperature changes in real time, and converting floor heat into thermoelectric electromotive force based on the Seebeck effect; obtaining overheating anomaly information of the battery pack based on the amplitude of the thermoelectric electromotive force, combined with the output voltage polarity and temperature spatial distribution characteristics of the flexible thermoelectric material array; in the event of a power failure of the vehicle's electronic control system, controlling the vehicle door to execute a self-driven unlocking mode through a graded response based on the overheating anomaly information, the self-driven unlocking mode includes: an electromagnetic self-driven mode in which the thermoelectric electromotive force is transmitted to an electromagnetic engagement mechanism in the door lock actuator to drive the door lock mechanical unloading with the thermoelectric electromotive force; and a thermomechanical drive mode in which the heat collected from the flexible thermoelectric material array is transferred to a shape memory alloy element in the door lock actuator through a heat conduction path to open the door lock by generating mechanical pulling force through phase change contraction.

[0050] This embodiment utilizes a flexible thermoelectric material array laid between the vehicle floor and the battery pack to collect temperature in real time and convert it into a thermoelectric electromotive force based on the Seebeck effect. Simultaneously, it accurately obtains battery pack overheating anomaly information based on the amplitude, polarity, and spatial temperature distribution characteristics of the thermoelectric electromotive force. This enables a self-driven unlocking mode that responds in stages based on the anomaly information, using either an electromagnetic self-drive mode or a thermomechanical drive mode, even in the event of a complete failure of the vehicle's electrical system, no backup power, and no active operation by the occupants. Compared to existing technologies, this allows for automatic door unlocking using only the heat generated by the battery's thermal runaway, providing both electrical and thermal energy as independent physical driving sources, even in the event of a complete failure of the vehicle's electrical system, no backup power, and no active operation by the occupants.

[0051] To better understand the above technical solutions, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present invention can be understood more clearly and thoroughly, and that the scope of the present invention can be fully conveyed to those skilled in the art.

[0052] Specifically, refer to Figure 1 As shown, the emergency door control method based on thermoelectric conversion proposed in this embodiment may include the following steps S100 to S300:

[0053] S100 utilizes a flexible thermoelectric material array laid between the vehicle floor and the battery pack to collect floor temperature changes in real time and convert floor heat into thermoelectric electromotive force based on the Seebeck effect.

[0054] In this embodiment, the flexible thermoelectric material array is composed of multiple independent thermoelectric conversion units arranged in a spatial grid pattern corresponding to the cell layout within the battery pack. The main material of each thermoelectric conversion unit is a flexible thermoelectric film based on bismuth telluride (Bi2Te3)-based composite material, with a thickness of 0.5mm-2mm, characterized by its flexibility, light weight, and low thermal conductivity. In terms of installation structure, the flexible thermoelectric material array is fixed in the interlayer between the vehicle floor sheet metal and the battery pack upper shell. Specifically, the hot end face of each thermoelectric unit is tightly bonded to the inner surface of the vehicle floor using highly thermally conductive silicone grease or adhesive, allowing direct contact and sensing of the floor temperature; its cold end face faces the bottom of the vehicle body and maintains a thermal insulation gap or insulation layer between it and the battery pack upper shell to keep the cold end temperature relatively low, thereby creating an effective temperature difference between the hot and cold ends.

[0055] When the battery pack experiences thermal runaway or localized overheating, heat is transferred through the battery pack's upper casing to the cold end and surrounding areas of the flexible thermoelectric material array, causing a rapid rise in the vehicle's floor temperature. As the hot end of the thermoelectric film heats up, while the cold end remains relatively cool, a temperature difference is created between them. According to the Seebeck effect, driven by this temperature difference, charge carriers within the thermoelectric film diffuse from the hot end to the cold end, generating a thermoelectric electromotive force across the thermoelectric unit. Multiple thermoelectric units can be connected in series or a hybrid series-parallel configuration to output a sufficiently high voltage or current to drive the door lock actuator. Seebeck effect instantaneous power generation:

[0056] ;

[0057] In the formula, N is the number of thermocouple pairs, S is the Seebeck coefficient, and T is the number of thermocouple pairs. battery T is the hot end temperature. cabin This refers to the cold end temperature. In the extreme case of battery thermal runaway, the electrical energy generated by the temperature difference can drive the pre-configured low-impedance electromagnetic coil in the electromagnetic engagement mechanism to forcibly push open the physical latch of the door lock. If a higher voltage is required, the number of series stages N can be increased or a material with a higher Seebeck coefficient can be selected.

[0058] In practical applications, each thermoelectric conversion unit is equipped with independent positive and negative leads, which converge into a high thermal conductivity composite busbar. This busbar simultaneously performs the functions of electrical energy transmission and heat conduction: on the one hand, it collects the thermoelectric electromotive force generated by each unit and outputs it directly to the electromagnetic engagement mechanism or graded response control module of the door lock actuator; on the other hand, through the metal thermally conductive part of the busbar, it concentrates the heat transfer to the heat collection end of the shape memory alloy element, providing a heat source for the thermomechanical drive mode.

[0059] In addition, the flexible thermoelectric material array is also connected to a voltage detection module, which is used to collect the voltage amplitude and polarity of each thermoelectric unit in real time. The voltage signal is used to calculate the temperature rise rate and temperature spatial distribution characteristics, and to determine the direction of the heat source, thus providing an accurate basis for subsequent abnormal state judgment.

[0060] S200: Based on the amplitude of the thermoelectric potential, combined with the output voltage polarity and temperature spatial distribution characteristics of the flexible thermoelectric material array, the overheating anomaly information of the battery pack is obtained.

[0061] In this embodiment, the overheating anomaly information includes two levels: high-temperature warning and thermal runaway. The high-temperature warning state occurs when a vehicle is parked under direct sunlight, and the floor temperature can reach 50°C. However, the entire floor surface heats up uniformly, the voltage distribution is flat (without spikes), and the rate of temperature rise (amplitude of the thermoelectric potential) changes slowly, approaching zero. The thermal runaway state occurs on top of the high-temperature warning state, where the floor temperature continues to increase, the temperature rise curve grows exponentially, and voltage distribution is accompanied by spikes. Specifically, refer to... Figure 2 As shown, step S200 may include the following sub-steps S210 to S240:

[0062] S210. By calibrating the historical temperature rise curves under two operating conditions—normal vehicle operation and thermal runaway—the thermal runaway threshold of the battery is obtained.

[0063] Furthermore, the thermal runaway threshold is configured with two temperature thresholds: 50°C for the first temperature threshold and 70°C for the second temperature threshold. The first temperature threshold is one of the criteria for judging a high-temperature warning state. For example, when the floor temperature exceeds 50°C, the vehicle enters a high-temperature state. At this point, it cannot be confirmed whether it is battery thermal runaway (it may be due to normal heat generation after prolonged driving or ambient high temperature). Therefore, a high-temperature warning needs to be sent to the user to remind the occupants to pay attention to the abnormality, but it will not trigger the door locks to open automatically to avoid accidental operation. The second temperature threshold is also one of the criteria for judging a thermal runaway state. For example, when the floor temperature exceeds 70°C, there may be a high risk of thermal runaway. However, to avoid misjudgment caused by a single-point absolute temperature threshold (such as local high temperature near the exhaust pipe), it is necessary to further confirm the situation by combining the amplitude of the thermoelectric potential, the polarity of the output voltage of the flexible thermoelectric material array, and the temperature spatial distribution characteristics before finally determining it to be a thermal runaway state.

[0064] S220. When the amplitude of the thermoelectric potential exceeds the thermal runaway threshold and the floor temperature exceeds the preset second temperature threshold, the battery pack is determined to be in an overheating abnormality and a thermal runaway state.

[0065] S230. Under thermal runaway conditions, based on the output voltage polarity and temperature spatial distribution characteristics of the flexible thermoelectric material array, the thermal runaway region of the battery is located to obtain the local overheated region of the battery pack.

[0066] Further, step S230 may include the following sub-steps S231 to S233:

[0067] S231. Obtain the output voltage polarity of each unit in the flexible thermoelectric material array, and perform heat source spatial analysis on the output voltage polarity to obtain the heat source transfer direction.

[0068] To further explain, when the hot end face of the flexible thermoelectric material array is closely attached to the inner surface of the vehicle floor, the cold end face faces the bottom of the vehicle body, and a heat insulation gap or heat insulation layer is provided between it and the upper shell of the battery pack, the output voltage of the thermoelectric unit that generates high temperature is positive, indicating that the heat is transferred from bottom to top, that is, from the floor upwards.

[0069] S232. When the heat source is transferred upwards from the floor, obtain the spatial distribution field of the temperature gradient of the flexible thermoelectric material array.

[0070] S233. If there is a local peak feature in the temperature gradient spatial distribution field, then the location corresponding to the local peak feature is determined to be a local overheating area of ​​the battery pack.

[0071] S240. Based on the information on the distribution of the local overheated area and the location of the occupants inside the vehicle, generate the emergency opening priority of the vehicle door. The information on the distribution of the occupants inside the vehicle includes the presence status and location of the occupants in each seat.

[0072] Further, step S230 may include the following sub-steps S231 to S233:

[0073] S241. Obtain the existence status and position of each member in the car, and determine the associated seat set corresponding to each door.

[0074] S242. Based on the thermal radiation distance between each door and the local overheated area, and combined with the number of members in the set of seats associated with that door, determine the emergency avoidance coefficient of each door.

[0075] S243. Generate the emergency opening priority of the car doors in descending order of emergency avoidance coefficient.

[0076] Among them, the emergency avoidance coefficient is inversely proportional to the distance of thermal radiation, and directly proportional to the number of members present.

[0077] S300: In the event of a power failure in the vehicle's electronic control system, based on overheating anomaly information, the door is controlled to execute a self-driven unlocking mode through a graded response. The self-driven unlocking modes include: an electromagnetic self-driven mode in which the thermoelectric electromotive force is transmitted to the electromagnetic engagement mechanism in the door lock actuator to drive the door lock mechanical unloading; and a thermomechanical drive mode in which the heat collected from the flexible thermoelectric material array is transferred to the shape memory alloy element in the door lock actuator through a heat conduction path to generate mechanical pulling force to open the door lock through phase change contraction.

[0078] In this embodiment, the graded response is divided into three levels: Level 1 response corresponds to the high-temperature warning state, Level 2 response corresponds to the electromagnetic self-drive mode under thermal runaway state, and Level 3 response corresponds to the thermomechanical drive mode after the electromagnetic self-drive fails under thermal runaway state. All of the above graded responses are executed under the preset condition that the vehicle's electronic control system is powered off or about to be powered off, and do not rely on the on-board controller or low-voltage bus signals. Specifically, refer to... Figure 3 As shown, step S300 may include the following sub-steps S310 to S330:

[0079] S310: When the overheating abnormality information is in the high temperature warning state and the floor temperature is higher than the preset first temperature threshold, send an audible and visual alarm signal to the preset alarm unit and upload the floor temperature data to the cloud.

[0080] Furthermore, when step S200 determines that the current overheating anomaly is a high-temperature warning state (e.g., the local floor temperature reaches 50°C but does not meet the characteristics of thermal runaway), it first determines whether the vehicle's low-voltage electronic control system is still operating normally. If the low-voltage system still has power, the instrument panel warning lights and voice module are activated via the body controller to issue a high-temperature warning; if the low-voltage system has lost power, the weak voltage output from the flexible thermoelectric material array directly drives a low-power audible and visual alarm independent of the vehicle bus. Simultaneously, the current temperature data, voltage distribution heatmap, and location information are uploaded to the cloud or vehicle remote monitoring platform via the optical communication module (multimode optical cable + optical transceiver) for background analysis and fire alarm. During the Level 1 response, no automatic door unlocking actions are performed to avoid accidental operation under non-hazardous conditions.

[0081] S320: When the overheating abnormality information indicates thermal runaway and the floor temperature is higher than the preset second temperature threshold, the door is controlled to execute the electromagnetic self-drive mode, using the thermoelectric potential to drive the door lock to mechanically unload.

[0082] Furthermore, when step S200 determines that the overheating anomaly has escalated to a thermal runaway state, and the calculated floor temperature exceeds the second temperature threshold (70°C), a secondary response is immediately initiated: the electromagnetic self-drive mode. This mode bypasses any vehicle controller or electronic switch, instead directly transmitting the thermoelectric electromotive force output from the flexible thermoelectric material array to the electromagnetic engagement mechanism in the door lock actuator via an independent low-impedance wire. The electromagnetic engagement mechanism integrates a low-impedance electromagnetic coil (e.g., starting voltage 3V~12V, current 0.5A~2A). When the thermoelectric electromotive force is sufficient, the electromagnetic coil generates attraction, overcoming the holding force of the door lock spring or pawl, causing the door lock to mechanically unload, and the door automatically opens under gravity or internal / external pressure difference. To avoid the risk of arcing or short circuits, a normally closed thermal fuse (operating temperature set at 120°C) can be connected in series in this circuit. It automatically disconnects the protection circuit only when the thermal runaway temperature is too high, but by then the heat is sufficient to trigger the next stage of thermomechanical drive.

[0083] If the thermoelectric electromotive force amplitude is insufficient to directly drive the electromagnet, wait 0.5 to 2 seconds until the temperature and voltage rise further before attempting to drive it. Alternatively, this implementation can increase the number of thermoelectric units in series or use a boost capacitor to multiply the voltage, ensuring sufficient starting voltage is output even at lower temperature differences.

[0084] S330, in electromagnetic self-drive mode and when the door is not detected to be open, control the door to execute thermomechanical drive mode, so that the heat collected from the flexible thermoelectric material array is transferred to the shape memory alloy element in the door lock actuator through the heat conduction path, and the mechanical pulling force is generated by phase change contraction to open the door lock.

[0085] Furthermore, after the electromagnetic self-drive mode is activated, the door lock position is detected via an independent microswitch. If the door remains closed after a preset time, it automatically switches to a third-level response: thermomechanical drive mode. In thermomechanical drive mode, instead of relying on electrical energy, the heat collected by the flexible thermoelectric material array is directly transferred through a highly thermally conductive path to the shape memory alloy (SMA) element integrated in the door lock actuator. This SMA element is a nickel-titanium (NiTi) alloy wire with a phase transformation temperature set between 70°C and 90°C. When the heat conduction causes its temperature to exceed the phase transformation point, the alloy crystal structure transforms from martensite to austenite, generating approximately 4% to 8% contraction strain and outputting a large contraction force. This contraction force acts directly on the mechanical unlocking fork of the door lock through a lever, forcibly pulling the bolt back to achieve physical unlocking.

[0086] Furthermore, to ensure rapid and sufficient heat transfer to the SMA element, a heat collection chamber is installed inside the door lock actuator. This chamber is made of a highly thermally conductive metal, filled with thermally conductive silicone grease, and directly connected to the heat collection plate on the back of the flexible thermoelectric material array via a metal thermally conductive busbar. Even if the vehicle is completely powered off and the electromagnet fails, as long as heat from the floor continues to be conducted to the heat collection chamber, the SMA element will reach the phase change temperature within a few seconds and trigger the unlocking. Simultaneously, the heat capacity of this chamber can maintain the phase change temperature for several minutes, providing sufficient window of opportunity for occupants to escape.

[0087] It's worth noting that the thermomechanical drive mode is a purely physical backup channel independent of the electromagnetic self-drive mode. Both share a single door lock mechanical unloading mechanism, but their drive sources do not interfere with each other. In practical design, the SMA contraction force and electromagnetic attraction force can be applied in parallel to the same unlocking lever; either drive being effective will open the door. Furthermore, in cases of extremely severe thermal runaway, where the floor temperature instantaneously exceeds 120°C, the electromagnetic self-drive mode may fail prematurely due to circuit burnout. In this situation, the thermomechanical drive mode can still independently complete the unlocking task, thus achieving true dual redundancy physical security.

[0088] Furthermore, this invention also proposes a vehicle door emergency control system based on thermoelectric conversion, used to implement the above-described vehicle door emergency control method based on thermoelectric conversion. The system includes:

[0089] A flexible thermoelectric floor array is laid between the vehicle floor and the battery pack to collect floor temperature changes in real time and convert thermal energy into electrical energy.

[0090] The heat transfer bus is connected to the flexible thermoelectric floor array and the door lock actuator respectively, and is used to transfer the heat energy or electrical energy of the flexible thermoelectric floor array to the door lock actuator.

[0091] The door lock actuator, integrated into the door lock body, includes an electromagnetic engagement mechanism and a shape memory alloy element. The electromagnetic engagement mechanism is used to receive the thermoelectric electromotive force and directly drive the door lock to mechanically unload. The shape memory alloy element undergoes phase change and contraction under the action of heat conduction through the heat transfer bus to generate mechanical unlocking force.

[0092] Furthermore, the flexible thermoelectric floor array uses Bi2Te3-based composite thermoelectric thin film material; the hot end of each thermoelectric unit in the flexible thermoelectric floor array faces the vehicle floor surface, and the cold end faces the bottom of the vehicle body. Multiple thermoelectric units are arranged in a spatial grid to form a topology structure corresponding to the cell layout in the battery pack.

[0093] Furthermore, the heat conduction bus is a composite structure of optical fiber and metal heat conduction bus; the optical fiber is used to transmit temperature signals; the metal heat conduction bus is used to transmit electrical energy to the electromagnetic engagement mechanism in the door lock actuator, and to transmit thermal energy to the shape memory alloy element in the door lock actuator.

[0094] Furthermore, the door lock actuator is equipped with a heat collection chamber, which is connected to a flexible thermoelectric floor array via a thermally conductive material. This chamber is used to temporarily store heat and maintain the phase change time window of the shape memory alloy element.

[0095] Furthermore, the emergency control system does not interact with the vehicle's low-voltage bus and on-board controller via electrical signals, but operates using the thermal energy and thermoelectric potential generated under battery pack thermal runaway conditions.

[0096] In summary, this invention proposes a vehicle door emergency control method and system based on thermoelectric conversion. It employs a flexible thermoelectric material array laid between the vehicle floor and the battery pack to collect temperature data in real time and convert it into a thermoelectric electromotive force (EMF) based on the Seebeck effect. The method accurately obtains battery pack overheating anomaly information based on the amplitude, polarity, and spatial temperature distribution characteristics of the EMF. This enables a self-driven unlocking mode that responds in stages to either electromagnetic self-drive mode or thermomechanical drive mode when the vehicle's electronic control system loses power, based on the anomaly information. Compared to existing technologies, this invention offers the following technical advantages:

[0097] 1. Fully self-powered by thermal runaway, without relying on external power source: Thermoelectric materials are used to directly convert the waste heat generated by thermal runaway into driving electrical or mechanical energy, eliminating the need for any backup power source such as on-board batteries or supercapacitors, thus fundamentally avoiding the risk of backup power failure in high-temperature environments.

[0098] 2. Dual self-opening mode redundancy: The electromagnetic self-drive mode and the thermomechanical drive mode are independent of each other and serve as backups for each other. Even if one drive path is damaged due to extreme high temperature, the other can still independently complete the unlocking action, which significantly improves the escape success rate under extreme conditions.

[0099] 3. Physical isolation, unaffected by electronic control system failure: The entire unlocking link does not pass through the vehicle controller, CAN bus or any electronic switch, forming an emergency channel that is completely physically isolated from the vehicle's electrical system. Even if the vehicle's computer and wiring harness are burned out, the door lock can still be opened normally.

[0100] 4. Precise overheat detection to avoid false triggering: Through comprehensive analysis of the amplitude, polarity, and spatial distribution characteristics of the thermoelectric potential, it can accurately identify battery thermal runaway rather than non-dangerous conditions such as high ambient temperature, effectively preventing accidental unlocking caused by high floor temperature in summer.

[0101] 5. Hierarchical control response: When the electronic control system has not completely failed, conventional electronic unlocking is used first. Only after power failure or electronic control failure will it automatically switch to physical self-drive mode, which takes into account both the convenience of daily use and the security in extreme situations.

[0102] Since the systems / devices described in the above embodiments of the present invention are systems / devices used to implement the methods of the above embodiments of the present invention, those skilled in the art can understand the specific structure and modifications of the systems / devices based on the methods described in the above embodiments of the present invention, and therefore will not be repeated here. All systems / devices used in the methods of the above embodiments of the present invention fall within the scope of protection of the present invention.

[0103] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0104] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, as well as combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions.

[0105] It should be noted that in the description of this invention, the word "a" or "an" preceding a component does not exclude the existence of multiple such components. This invention can be implemented by means of hardware comprising several different components and by means of a suitably programmed computer. The use of terms such as first, second, third, etc., is merely for convenience and does not indicate any order. These terms can be understood as part of the component names.

[0106] Furthermore, it should be noted that in the description of this specification, the terms "one embodiment," "some embodiments," "embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0107] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning of the basic inventive concept, can make other changes and modifications to these embodiments.

[0108] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from the spirit and scope of the invention.

Claims

1. A vehicle door emergency control method based on thermoelectric conversion, characterized in that, include: By using a flexible thermoelectric material array laid between the vehicle floor and the battery pack, the floor temperature change is collected in real time, and the floor heat is converted into thermoelectric electromotive force based on the Seebeck effect. Based on the amplitude of the thermoelectric potential, combined with the output voltage polarity and temperature spatial distribution characteristics of the flexible thermoelectric material array, the overheating anomaly information of the battery pack is obtained. In the event of a power failure in the vehicle's electronic control system, based on the overheating anomaly information, the door is controlled to execute a self-driven unlocking mode through a graded response. The self-driven unlocking mode includes: an electromagnetic self-driven mode in which the thermoelectric potential is transmitted to the electromagnetic engagement mechanism in the door lock actuator, and the thermoelectric potential drives the door lock to mechanically unload. In addition, the heat collected from the flexible thermoelectric material array is transferred to the shape memory alloy element in the door lock actuator through the heat conduction path, and the door lock is opened by a thermomechanical drive mode that generates mechanical pulling force through phase change contraction.

2. The method as described in claim 1, characterized in that, Based on the amplitude of the thermoelectric potential, combined with the output voltage polarity and temperature spatial distribution characteristics of the flexible thermoelectric material array, the overheating anomaly information of the battery pack is obtained, including: By calibrating the historical temperature rise curves under two operating conditions—normal vehicle operation and thermal runaway—the thermal runaway threshold of the battery can be obtained. When the amplitude of the thermoelectric potential exceeds the thermal runaway threshold and the floor temperature exceeds the preset second temperature threshold, the battery pack is judged to be in an overheating abnormality and a thermal runaway state. In the thermal runaway state, based on the output voltage polarity and temperature spatial distribution characteristics of the flexible thermoelectric material array, the thermal runaway region of the battery is located, and the local overheating region of the battery pack is obtained. Based on the information on the local overheated areas and the location distribution of occupants inside the vehicle, an emergency opening priority for the doors is generated. The information on the location distribution of occupants inside the vehicle includes the presence status and location of occupants in each seat.

3. The method as described in claim 2, characterized in that, Based on the output voltage polarity and temperature spatial distribution characteristics of the flexible thermoelectric material array, the thermal runaway region of the battery is located, and the local overheating regions of the battery pack are identified as follows: The output voltage polarity of each unit in the flexible thermoelectric material array is obtained, and the output voltage polarity is analyzed in the heat source space to obtain the heat source transfer direction. When the heat source transfers upward from the floor, the spatial distribution field of the temperature gradient of the flexible thermoelectric material array is obtained. If a local peak feature exists in the spatial distribution field of the temperature gradient, then the location corresponding to the local peak feature is determined to be a local overheating region of the battery pack.

4. The method as described in claim 2, characterized in that, Based on the distribution information of localized overheated areas and the positions of occupants inside the vehicle, the emergency opening priorities for the doors are generated as follows: Obtain the presence status and position of each member in the vehicle, and determine the associated seat set corresponding to each door; Based on the thermal radiation distance between each door and the local overheated area, and combined with the number of members in the set of seats associated with that door, the emergency avoidance coefficient of each door is determined. The emergency opening priority of the car doors is generated in descending order of emergency avoidance coefficient. Among them, the emergency avoidance coefficient is inversely proportional to the distance of thermal radiation, and directly proportional to the number of members present.

5. The method as described in claim 1, characterized in that, Based on the overheating anomaly information, the door is controlled to execute a self-driven unlocking mode through a graded response, including: When the overheating anomaly is in a high temperature warning state and the floor temperature is higher than the preset first temperature threshold, an audible and visual alarm signal is sent to the preset alarm unit, and the floor temperature data is uploaded to the cloud. When the overheating anomaly is in a state of thermal runaway and the floor temperature is higher than the preset second temperature threshold, the door is controlled to execute the electromagnetic self-drive mode, which uses the thermoelectric potential to drive the door lock to mechanically unload. In electromagnetic self-drive mode and when the door is not detected to be open, the door is controlled to execute thermomechanical drive mode, so that the heat collected from the flexible thermoelectric material array is transferred to the shape memory alloy element in the door lock actuator through the heat conduction path, and the mechanical pulling force is generated by phase change contraction to open the door lock.

6. A vehicle door emergency control system based on thermoelectric conversion, characterized in that, For implementing the thermoelectric conversion-based emergency door control method as described in any one of claims 1-5, the system comprises: A flexible thermoelectric floor array is laid between the vehicle floor and the battery pack to collect floor temperature changes in real time and convert thermal energy into electrical energy. The heat transfer bus is connected to the flexible thermoelectric floor array and the door lock actuator respectively, and is used to transfer the thermal energy or electrical energy of the flexible thermoelectric floor array to the door lock actuator. The door lock actuator, integrated into the door lock body, includes an electromagnetic engagement mechanism and a shape memory alloy element. The electromagnetic engagement mechanism is used to receive the thermoelectric electromotive force and directly drive the door lock to mechanically unload. The shape memory alloy element undergoes phase change and contraction under the action of heat conduction through the heat transfer bus to generate mechanical unlocking force.

7. The system as described in claim 6, characterized in that, The flexible thermoelectric floor array uses Bi2Te3-based composite thermoelectric thin film material; Each thermoelectric unit in the flexible thermoelectric floor array has its hot end facing the vehicle floor surface and its cold end facing the bottom of the vehicle body. Multiple thermoelectric units are arranged in a spatial grid to form a topology that corresponds to the cell layout inside the battery pack.

8. The system as described in claim 6, characterized in that, The heat transfer bus is a composite structure of optical fiber and metal heat-conducting bus. Optical fiber is used to transmit temperature signals; Metal thermally conductive busbars are used to transfer electrical energy to the electromagnetic engagement mechanism in the door lock actuator and to transfer thermal energy to the shape memory alloy elements in the door lock actuator.

9. The system as described in claim 6, characterized in that, The door lock actuator also has a heat collection chamber inside, which is connected to a flexible thermoelectric floor array through a heat-conducting material. This chamber is used to temporarily store heat and maintain the phase change time window of the shape memory alloy element.

10. The system as described in claim 6, characterized in that, The emergency control system does not interact with the vehicle's low-voltage bus and on-board controller via electrical signals. Instead, it operates using the thermal energy and thermoelectric potential generated under battery pack thermal runaway conditions.

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