Vehicle door unlocking control method and system after vehicle collision power failure

Abstract

The application relates to the technical field of vehicle safety control, and discloses a vehicle door unlocking control method and system after vehicle collision power failure, wherein the method comprises the following steps: S1, keeping an emergency driving path disconnected in a normal state, and charging a super capacitor and monitoring the state; S2, entering a collision unlocking mode when a collision signal is valid and a main power source is abnormal; S3, outputting a high-resistance control instruction to a vehicle body side electronic control unit by a collision power module, so that a door lock driving output end enters a high-resistance state, and a path isolation switch in a conventional driving path is disconnected; S4, collecting a door lock motor end voltage and a loop current in an emergency driving path disconnected state, and judging a straight-through, back-priming or diagnosis conflict risk through energy limiting detection; and S5, turning on the emergency driving path when there is no risk, and unlocking by super capacitor power supply, and prohibiting turning on when there is risk. The system is used for executing the above method. The application can reduce parallel driving interference when the collision power module takes over, and improve the emergency unlocking reliability of the vehicle door.

Description

Technical Field

[0001] This invention relates to the field of vehicle safety control technology, and in particular to a method and system for controlling door unlocking after a vehicle collision and power failure. Background Technology

[0002] As vehicles become more electrified and intelligent, electric door locks, hidden door handles, and electric opening mechanisms are increasingly used in vehicles. After a collision, door locks usually need to be unlocked promptly to facilitate occupant escape and external rescue. However, in a collision, the low-voltage main power supply may lose its power supply capability due to reasons such as broken wiring harness, damaged battery, blown fuse, or power failure of the controller, causing the door lock motor to be unable to unlock using the conventional power supply path.

[0003] To improve the reliability of door unlocking after a collision, existing solutions typically include a collision power module with a supercapacitor. Under normal vehicle conditions, the main power supply charges the supercapacitor; when a collision occurs and the main power supply malfunctions, the supercapacitor can serve as an emergency power source to supply power to loads such as the door lock motor.

[0004] However, in some vehicle architectures, a conventional drive path is formed between the body-side electronic control unit and the door lock motor, while an emergency drive path is formed between the collision power module and the door lock motor. The two may be connected in parallel to the same door lock motor. If the collision power module does not confirm the status of the conventional drive path before taking over the door lock motor, a straight-through loop may be formed due to the body-side electronic control unit output not being completely turned off, the low-side switch being turned on, or the wiring harness being short-circuited, resulting in abnormal energy discharge of the supercapacitor or damage to the device.

[0005] In addition, the door lock motor may generate a back electromotive force or switching spike during the switching process. There may also be offline diagnostic excitation signals for the door lock motor during normal vehicle diagnostics. If the collision power module fails to identify the above-mentioned backflow or diagnostic conflict risk and then activates the emergency drive path, it may lead to malfunction, misdiagnosis, or emergency unlocking failure. Summary of the Invention

[0006] The purpose of this invention is to solve the problem in the prior art that the conventional drive path is risky before the collision power module takes over the door unlocking drive after a collision power failure. Therefore, this invention proposes a door unlocking control method and system after a vehicle collision power failure.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a method for controlling door unlocking after a vehicle collision and power failure, wherein the vehicle includes a vehicle-side electronic control unit, a collision power module, a door lock motor, a main power supply, and a supercapacitor, wherein the vehicle-side electronic control unit and the door lock motor form a conventional drive path, and the collision power module and the door lock motor form an emergency drive path, comprising the following steps: S1: Under normal conditions, the collision power module keeps the emergency drive path disconnected and charges and monitors the status of the supercapacitor. S2: When the collision signal is valid and the main power supply is abnormal, the collision power module enters the collision unlocking mode; S3: In the collision unlocking mode, the collision power module controls the conventional drive path to enter the isolation state, including: outputting a high-resistance control command to the vehicle-side electronic control unit so that the door lock drive output terminal of the vehicle-side electronic control unit enters the high-resistance state; and controlling the path isolation switch set in the conventional drive path to open. S4: When the emergency drive path is kept disconnected, the collision power module collects the voltage at the door lock motor terminal and the circuit current, and determines whether there is a risk of direct connection, backflow or diagnostic conflict in the normal drive path through the energy limiting detection method. The energy limiting detection method is to apply a detection energy signal lower than the drive action threshold to the circuit where the door lock motor is located. S5: If the aforementioned risk does not exist, the collision power module activates the emergency drive path and the supercapacitor supplies power to the door lock motor for unlocking; if the aforementioned risk exists, the activation of the emergency drive path is prohibited.

[0008] The present invention also provides a vehicle door unlocking control system after a vehicle collision and power failure, for executing the above-described vehicle door unlocking control method after a vehicle collision and power failure, comprising: Main power supply; Door lock motor; A vehicle-side controller forms a conventional drive path with the door lock motor; the vehicle-side controller is a vehicle-side electronic control unit. The collision power module includes a supercapacitor, a controller, a voltage conversion circuit, a sampling circuit, and an emergency drive circuit. The collision power module forms an emergency drive path with the door lock motor. The controller is connected to the voltage conversion circuit, the sampling circuit, and the emergency drive circuit, respectively.

[0009] The beneficial effects of the technical solution provided by this invention include at least the following: This invention reduces the risk of a through circuit when the vehicle-side electronic control unit is not completely shut down by controlling the conventional drive path to enter an isolated state before the emergency drive path is activated by the collision power module. This avoids abnormal discharge of the supercapacitor's emergency power supply energy through the conventional drive path and reduces the possibility that the door lock motor will not receive effective drive power after a collision.

[0010] This invention collects the voltage and circuit current at the door lock motor terminals while the emergency drive path remains disconnected, and uses an energy-limiting detection method to determine the status of the conventional drive path. This allows for a safe confirmation before takeover without triggering the door lock motor. Because the detected energy signal is below the minimum energy required to drive the door lock motor, it can identify whether there are short circuits, low resistance, or abnormal coupling states in the conventional drive path while avoiding false locking or malfunctions.

[0011] This invention determines the risks of shoot-through, backflow, or diagnostic conflict based on the door lock motor terminal voltage, circuit current, and offline diagnostic excitation signal, thereby reducing mutual interference when the collision power module and the vehicle-side electronic control unit drive the same door lock motor in parallel. This method enables the collision power module to identify abnormal electrical states in the normal drive path before taking over the door lock motor, thus reducing the impact of back electromotive force, diagnostic current, or residual switch states on the emergency unlocking process.

[0012] This invention improves the reliability of door unlocking after a collision power failure by continuously monitoring the voltage and circuit current at the door lock motor after the emergency drive path is activated, and disconnecting the emergency drive path when abnormal conditions persist for more than a preset filtering time. By setting a preset filtering time, the probability of false protection caused by transient spikes or short-term disturbances can be reduced, while timely disconnection of the emergency drive path when continuous abnormalities occur protects the collision power module and door lock drive circuit. Attached Figure Description

[0013] To more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is an overall flowchart of the door unlocking control method provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the door unlocking control system provided in an embodiment of the present invention. Detailed Implementation

[0015] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a vehicle door unlocking control method and system based on the present invention after a vehicle collision and power failure. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0016] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0017] The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0018] The following describes in detail, with reference to the accompanying drawings, a specific scheme for a vehicle door unlocking control method and system provided by the present invention. The present invention aims to improve the reliability of the emergency unlocking process of the vehicle door after a collision, so that before the collision power module takes over the door lock motor, problems such as direct flow, backflow, or diagnostic conflicts may occur due to the unclear status of the conventional drive path.

[0019] Please see Figure 1 This invention illustrates a method for controlling door unlocking after a vehicle collision and power failure, provided by an embodiment of the present invention. The vehicle includes a vehicle-side electronic control unit (ECU), a collision power module (CPM), a door lock motor, a main power supply, and a supercapacitor. A conventional drive path is formed between the vehicle-side ECU and the door lock motor, and an emergency drive path is formed between the collision power module and the door lock motor. The method includes the following steps: S1: Under normal conditions, the collision power module keeps the emergency drive path disconnected and charges and monitors the status of the supercapacitor.

[0020] Specifically, when the vehicle is not involved in a collision and the main power supply is in normal working order, the vehicle-side electronic control unit drives the door lock motor to perform locking or unlocking actions according to the vehicle control commands. At this time, the collision power module does not participate in the normal drive of the door lock motor, and the emergency drive path between the collision power module and the door lock motor remains disconnected, thereby avoiding interference from the emergency drive path to the normal door lock control process.

[0021] Under normal conditions, the collision power module can charge the supercapacitor through a voltage conversion circuit. This voltage conversion circuit can be a buck-boost circuit, a step-down circuit, a boost circuit, or other power conversion circuit capable of transferring energy between the main power supply and the supercapacitor. The collision power module can also collect status parameters of the supercapacitor, such as voltage, current, and temperature, through a sampling circuit to determine whether the supercapacitor is in a state suitable for emergency unlocking.

[0022] It is worth noting that the status monitoring in step S1 is not limited to monitoring the voltage of the supercapacitor. In other embodiments, the collision power module can also determine the availability status of the supercapacitor based on its charging status, discharging status, temperature status, or historical fault status, and record fault information or report status information to the vehicle control system when the availability status is abnormal.

[0023] S2: When the collision signal is valid and the main power supply is abnormal, the collision power module enters the collision unlock mode.

[0024] Specifically, collision signals can originate from the airbag controller, collision sensors, inertial sensors, vehicle-side electronic control units, body controller, or collision messages within the vehicle network. The collision power module can receive collision signals via hard-wired signals, communication messages, or local sensor signals. When a collision signal meets preset valid conditions, the collision power module determines that the vehicle is in the midst of a collision event.

[0025] In step S2, a main power supply malfunction is determined based on at least one of the following: the main power supply voltage is lower than a preset power-off threshold, or the main power supply connection is interrupted. The main power supply voltage can be detected by the sampling circuit in the collision power module. The preset power-off threshold can be calibrated based on the rated voltage of the vehicle's low-voltage system, the minimum operating voltage of the door lock motor, and the operating range of the power conversion circuit. The main power supply connection interruption can be determined based on changes in the main power supply input voltage, changes in the main power supply input current, or the main power supply connection status signal.

[0026] When communication between the vehicle-side electronic control unit and the collision power module is interrupted, or when the periodic status signal of the vehicle-side electronic control unit is lost, the collision power module will determine the status of the normal drive path as unconfirmable. At this time, even if the collision power module cannot directly confirm the door lock drive output status on the vehicle-side electronic control unit side, it will not directly activate the emergency drive path, but will instead proceed to the subsequent isolation and risk detection process.

[0027] It is worth noting that the collision unlocking mode is an emergency control mode executed by the collision power supply module in the event of a collision and power failure. In this mode, the collision power supply module prioritizes safety confirmation before the door lock motor takes over, isolation of the normal drive path, determination of the emergency drive path continuity, and emergency unlocking control.

[0028] S3: In the collision unlocking mode, the collision power module controls the conventional drive path to enter the isolation state, including: outputting a high-resistance control command to the vehicle-side electronic control unit so that the door lock drive output terminal of the vehicle-side electronic control unit enters the high-resistance state; and controlling the path isolation switch set in the conventional drive path to open.

[0029] Specifically, the conventional drive path refers to the electrical path between the vehicle-side electronic control unit and the door lock motor used for normal door lock motor operation. This path can include an H-bridge drive circuit, high-side switch, low-side switch, relays, power MOSFETs, or other door lock drive devices.

[0030] If the collision power module directly outputs emergency drive power to the door lock motor without isolating the normal drive path, a through circuit may be formed due to the incomplete shutdown of the drive devices on the vehicle side electronic control unit side, or reverse current may be generated due to the body diodes, protection devices, and wiring harness paths of the drive devices.

[0031] In step S3, controlling the regular drive path to enter the isolation state includes the following steps: S31: Send a high-impedance control signal to the vehicle-side electronic control unit, causing the door lock drive output of the vehicle-side electronic control unit to enter a high-impedance state.

[0032] Specifically, the high-impedance control signal can be a communication message, a hard-wired control signal, an enable / disable signal, or a fault protection signal. When the vehicle-side electronic control unit receives the high-impedance control signal, its door lock drive output terminal enters a high-impedance state, so that the door lock drive output terminal does not actively provide drive current to the door lock motor, nor does it actively pull the door lock motor terminal to the main power supply or vehicle ground.

[0033] In one specific implementation, if the vehicle-side electronic control unit can maintain communication with the collision power module, the collision power module requests the vehicle-side electronic control unit to turn off the door lock drive output through a communication message; if communication is unavailable, the collision power module directly processes the situation as unconfirmed and continues to execute the path isolation switch disconnection and energy limitation detection process.

[0034] S32: Controls the path isolation switch set in the normal drive path to disconnect, so as to form electrical isolation between the vehicle-side electronic control unit and the door lock motor.

[0035] Specifically, the path isolation switch can be a relay, a power MOSFET, a back-to-back MOSFET, a smart high-side switch, a smart low-side switch, or other switching devices capable of disconnecting the conventional drive path. The path isolation switch is installed between the vehicle-side electronic control unit and the door lock motor to cut off the conventional drive path when the collision power module enters the collision unlocking mode, reducing the impact of the vehicle-side electronic control unit circuitry on the emergency drive path.

[0036] S33: Based on the disconnection feedback signal of the path isolating switch and the change in the voltage at the door lock motor terminal, confirm that the normal drive path has entered the isolation state.

[0037] Specifically, after receiving the disconnection feedback signal from the path isolating switch, the collision power module collects the voltage at the door lock motor terminal as the isolation confirmation reference voltage, and determines the polarity of the auxiliary detection signal based on the isolation confirmation reference voltage. When the isolation confirmation reference voltage is higher than the preset intermediate voltage, a weak pull-down signal is applied to the door lock motor side through the energy-limiting detection branch; when the isolation confirmation reference voltage is not higher than the preset intermediate voltage, a weak pull-up signal is applied to the door lock motor side through the energy-limiting detection branch.

[0038] During the application of the auxiliary detection signal, the voltage at the door lock motor terminals and the detection current of the power limiting detection branch are collected. When the voltage at the door lock motor terminals changes along a preset direction corresponding to the auxiliary detection signal, and the voltage change reaches a preset following threshold, and the detection current is less than a preset isolation confirmation current threshold, the conventional drive path is confirmed to have entered an isolation state. When the voltage at the door lock motor terminals does not change along the preset direction, or the detection current reaches the preset isolation confirmation current threshold, the conventional drive path is determined to have failed to isolate or is in an unconfirmable state.

[0039] The disconnection feedback signal of the path isolating switch can be obtained from the status feedback terminal of the switching device itself, the fault feedback terminal of the driver chip, the current feedback signal of the sampling resistor, or the voltage change across the switch. The voltage change at the door lock motor terminal can include the voltage change of the door lock motor terminal relative to the vehicle body ground, the differential voltage change across the door lock motor, and the stable state of the door lock motor terminal voltage after the isolation operation.

[0040] It is worth noting that the purpose of step S33 is to avoid relying solely on control commands to determine whether isolation is successful. The collision power module not only issues isolation control commands, but also needs to confirm that the normal drive path has indeed entered the isolation state based on feedback signals or voltage status, thereby reducing the risk of misjudgment caused by path isolation switch jamming, abnormal output of the vehicle side electronic control unit, or wiring harness short circuit.

[0041] S4: When the emergency drive path is kept disconnected, the collision power module collects the voltage at the door lock motor terminal and the circuit current, and determines whether there is a risk of direct connection, backflow, or diagnostic conflict in the normal drive path through the energy limiting detection method. The energy limiting detection method is to apply a detection energy signal lower than the drive action threshold to the circuit where the door lock motor is located.

[0042] Specifically, "emergency drive path remains disconnected" means that the collision power module has not yet output the emergency drive power from the supercapacitor to the door lock motor. In this state, the collision power module only performs low-energy detection on the circuit containing the door lock motor through the sampling circuit and the current-limiting detection branch, without applying enough drive energy to the door lock motor to generate an unlocking action.

[0043] In step S4, the door lock motor terminal voltage includes the voltage of at least one terminal of the door lock motor relative to the vehicle body ground and the differential voltage across the two ends of the door lock motor. The loop current includes the drive current flowing through the door lock motor and the reverse current flowing from the door lock motor side to the collision power module side.

[0044] Specifically, by simultaneously collecting terminal voltage and loop current, the collision power module can identify whether there is a low-resistance path, reverse power supply path, abnormal pull-down or abnormal rise in the circuit where the door lock motor is located.

[0045] In step S4, the energy limitation detection method includes the following steps: S41: With the emergency drive path kept disconnected, the voltage at the door lock motor terminal is collected as the reference voltage.

[0046] Specifically, before applying a detection energy signal, the collision power module collects the voltage at the door lock motor terminal and uses this voltage as the reference voltage for subsequent judgment. The reference voltage is used to represent the natural electrical state of the circuit where the door lock motor is located when there is no detection excitation.

[0047] S42: Apply a detection energy signal to the circuit where the door lock motor is located through the current limiting detection branch, wherein the energy of the detection energy signal is lower than the minimum energy required to drive the door lock motor to produce an action.

[0048] Specifically, the current-limiting detection branch may include a current-limiting resistor, a constant current source, a current-limiting switch, a pulse-driven switch, or a combination thereof. The detected energy signal may be a short-time voltage pulse, a short-time current pulse, or a detection excitation of limited energy. The amplitude, duration, and number of outputs of the detected energy signal can be calibrated according to the door lock motor's action threshold and the resolution of the sampling circuit.

[0049] It is important to note that the detection energy signal is different from the emergency unlocking drive signal. The energy of the detection energy signal is lower than the minimum energy required to drive the door lock motor to produce an action, so it will not cause the door lock motor to produce an actual unlocking action. Its function is only to detect the electrical state of the circuit where the door lock motor is located.

[0050] S43: During the application of the detection energy signal, the voltage change at the door lock motor terminal and the circuit current are collected.

[0051] Specifically, the change in voltage at the door lock motor terminals can be the voltage difference before and after the application of the detection energy signal, or the change in the voltage slope or peak value during the application of the detection energy signal. The loop current can be acquired through a sampling resistor, a Hall current sensor, the current detection terminal of the driver chip, or a current mirror circuit.

[0052] When there is a risk of shoot-through or low resistance in the conventional drive path, the applied energy detection signal may manifest as an abnormal increase in loop current, failure of the terminal voltage to enter the preset voltage window, or a rapid drop in the terminal voltage. When a reverse current path exists, it may manifest as an increase in reverse current, an abnormal rise in the terminal voltage of the door lock motor, or a change in the terminal voltage direction inconsistent with the energy detection signal.

[0053] S44: After the detection energy signal is removed, the voltage decay time at the door lock motor terminal is collected.

[0054] Specifically, the terminal voltage decay time refers to the time required for the door lock motor terminal voltage to recover from the detected voltage to a preset voltage range or near a reference terminal voltage after the energy detection signal is removed. This decay time can be used to determine the equivalent impedance state of the circuit in which the door lock motor is located. When the conventional drive path is in an isolated state, the terminal voltage usually decays according to the preset high-resistance circuit characteristics; when the conventional drive path has a low-resistance path, a short-circuit path, or a reverse-flow path, the terminal voltage decay time will deviate from the preset range.

[0055] S45: When the voltage change at the door lock motor terminal is within a preset voltage window, the loop current is less than the first preset threshold, and the voltage decay time at the door lock motor terminal is greater than the second preset threshold, it is determined that there is no risk of direct connection or backflow in the conventional drive path.

[0056] Specifically, the preset voltage window, the first preset threshold, and the second preset threshold can be calibrated based on the door lock motor parameters, wiring harness impedance, current limiting detection branch parameters, sampling circuit accuracy, and the vehicle's electrical environment. If the voltage change at the door lock motor terminal is not within the preset voltage window, or the loop current is not less than the first preset threshold, or the voltage decay time at the door lock motor terminal is not greater than the second preset threshold, the collision power module can determine that there is a risk of direct connection or backflow in the conventional drive path and prohibit the conduction of the emergency drive path.

[0057] In step S4, the assessment of conflict risk includes: During the period when the collision power module does not send a drive command to the door lock motor, it detects whether the voltage at the door lock motor terminal changes periodically within a preset detection period, and detects whether the circuit current is within a preset diagnostic current range. When the voltage at the door lock motor terminal changes periodically and the circuit current is within the preset diagnostic current range, an offline diagnostic excitation signal is detected in the normal drive path, and a diagnostic conflict risk is determined.

[0058] Specifically, under normal vehicle conditions, the vehicle-side electronic control unit may perform offline diagnostics on the door lock motor and wiring harness through low-current excitation, periodic voltage detection, or switch status detection. The energy of these diagnostic signals is usually insufficient to drive the door lock motor, but they will cause periodic changes in the door lock motor's terminal voltage or circuit current. If the collision power module directly activates the emergency drive path at this time, it may lead to superposition or conflict between the diagnostic signals and the emergency drive signals. Therefore, when the collision power module identifies an offline diagnostic excitation signal, it treats it as a diagnostic conflict risk and prohibits or delays the activation of the emergency drive path.

[0059] S5: If there is no risk, the collision power module will activate the emergency drive path and the supercapacitor will supply power to the door lock motor to unlock it; if there is a risk, the emergency drive path will be deactivated.

[0060] Specifically, when the collision power module confirms, according to S3 and S4, that the normal drive path is in an isolated state and there is no risk of direct connection, backflow, or diagnostic conflict, the collision power module activates the emergency drive path. Activating the emergency drive path may include closing the emergency isolation switch, enabling the emergency drive circuit, starting the voltage conversion circuit, or controlling the supercapacitor to output unlocking power to the door lock motor.

[0061] In one specific implementation, the collision power module converts the supercapacitor voltage into a driving voltage suitable for the door lock motor through a voltage conversion circuit, and outputs an unlocking drive signal to the door lock motor through an emergency drive circuit. The emergency drive circuit can be an H-bridge drive circuit, a high-side drive circuit, a low-side drive circuit, or other circuits capable of driving the door lock motor.

[0062] If the collision power module determines that there is a risk of shoot-through, backflow, or diagnostic conflict, it will disable the emergency drive path. Disabling this path can include keeping the emergency disconnect switch open, disabling the emergency drive circuit, preventing the voltage conversion circuit from outputting to the door lock motor, or recording the corresponding fault status. This method prevents the supercapacitor from releasing energy into the door lock motor circuit under abnormal electrical conditions.

[0063] In step S5, after the collision power module turns on the emergency drive path, it continuously collects the door lock motor terminal voltage and circuit current within the preset monitoring period. When at least one of the following abnormal conditions is met and continues for more than the preset filtering time: the circuit current is greater than the preset overcurrent threshold, the door lock motor terminal voltage is lower than the preset drop threshold, or the reverse current is greater than the preset reverse current threshold, the emergency drive path is disconnected and the unlocking abnormal status is recorded.

[0064] Specifically, the preset filtering time is used to prevent short-term voltage spikes, motor commutation transients, or sampling noise from causing the collision power module to misjudge abnormalities. The collision power module will only execute the protection action of disconnecting the emergency drive path if the abnormal condition persists for more than the preset filtering time. The unlocked abnormal state can be stored in the collision power module's storage unit or reported to the vehicle control system via the communication interface.

[0065] In one implementation, after entering the collision unlocking mode, the collision power module can first perform a collision signal validity verification. Collision signal validity verification includes determining the source, duration, and consistency of the collision signal. Specifically, when the collision signal originates from a hard-wired trigger terminal, the collision power module can determine whether the level of the hard-wired trigger terminal remains valid within a preset verification time; when the collision signal originates from a vehicle communication message, the collision power module can determine whether the collision flag bit in the communication message is valid and whether the message meets a preset freshness requirement. Through the above methods, the possibility of the collision power module mistakenly entering the collision unlocking mode due to a single glitch signal, communication transient anomalies, or wiring harness interference can be reduced.

[0066] In one implementation, the determination of main power supply anomalies can be achieved by combining voltage judgment and connection status judgment. The controller of the collision power module collects the main power input voltage through the main power sampling terminal. When the main power input voltage is lower than a preset power failure threshold and remains below it for a preset confirmation time, the main power voltage is determined to be abnormal. The collision power module can also determine whether the main power supply connection is interrupted based on the main power input current, the status of the main power connection detection terminal, or the status of the main power pre-stage protection device. If at least one of the following conditions is met—main power voltage abnormality or main power supply connection interruption—the collision power module confirms the main power supply anomaly. Thus, the collision power module can enter collision unlocking mode under different scenarios such as main power drop, disconnection, or input connection failure.

[0067] In one implementation, the collision power module employs a conservative takeover strategy when it determines that the status of the vehicle-side electronic control unit (ECU) is unconfirmable. Unconfirmable status includes at least one of the following: communication interruption, loss of periodic status signals, ECU reset, or door lock drive status feedback timeout. When such unconfirmable status occurs, the collision power module does not directly assume the conventional drive path is in a safe state. Instead, it marks the conventional drive path as pending confirmation and continues to execute high-resistance control, path isolation switch disconnection, and energy-limiting detection procedures. Through this conservative takeover strategy, even if the vehicle-side ECU loses communication capability after a collision, the collision power module can still determine whether the emergency drive path should be allowed to operate based on local sampling and detection results.

[0068] In one embodiment, the path isolation switch can be located between the door lock drive output terminal of the vehicle-side electronic control unit and the door lock motor. The path isolation switch can be a relay, a power MOSFET, a smart high-side switch, or a back-to-back MOSFET. When the path isolation switch uses a power MOSFET, the collision power module can determine whether the path isolation switch has been opened by collecting the MOSFET gate drive state, the voltage difference across the switch, or the feedback signal from the drive chip. When the path isolation switch uses a relay, the collision power module can determine whether the relay contacts have been opened by relay drive feedback, contact state feedback, or changes in the voltage at the door lock motor terminal. These feedback methods can be used individually or in combination.

[0069] In one implementation, the voltage change at the door lock motor terminals can be used to assist in confirming whether the conventional drive path has entered the isolation state. Specifically, after the collision power module sends a high-impedance control signal and controls the path isolation switch to open, the collision power module collects the voltage of the first terminal of the door lock motor relative to the vehicle body ground, the voltage of the second terminal of the door lock motor relative to the vehicle body ground, and the differential voltage between the two terminals. When the above voltages are within a preset static voltage range within a preset observation time, and no abnormal state of being pulled high by the main power supply or pulled low by the vehicle body ground occurs, the collision power module can confirm that the conventional drive path has entered the isolation state. If either terminal of the door lock motor is still continuously pulled to the main power supply or the vehicle body ground, the collision power module determines that the conventional drive path may not be completely isolated.

[0070] In one embodiment, the current-limiting detection branch includes a detection power supply terminal, a current-limiting element, a detection switch, and a sampling node. The detection power supply terminal can be provided by the low-voltage regulated power supply inside the collision power module, or by a supercapacitor via a current-limiting circuit. The detection switch is briefly turned on under the control of the controller, allowing the detection energy signal to be applied to the circuit containing the door lock motor via the current-limiting element. The current-limiting element limits the current or energy of the detection energy signal, ensuring that the detection energy signal is insufficient to drive the door lock motor to produce mechanical action. The sampling node is used to collect changes in the voltage at the door lock motor terminal, the circuit current, or the voltage of the detection branch. Through this current-limiting detection branch, the collision power module can identify the electrical state of the circuit containing the door lock motor when the emergency drive path is not open.

[0071] In one implementation, the energy limitation detection method can employ single-pulse detection or multi-pulse detection. Single-pulse detection involves the collision power supply module applying a single detection energy signal to the circuit containing the door lock motor and making a judgment based on the change in terminal voltage, circuit current, and voltage decay time during that detection process. Multi-pulse detection involves the collision power supply module continuously applying multiple detection energy signals and judging the consistency of the multiple detection results. When multiple detection results meet preset conditions, the collision power supply module determines that there is no risk of shoot-through or backflow in the conventional drive path; when any detection result shows an abnormal increase in circuit current, an abnormal drop in terminal voltage, or an abnormal decay time, the collision power supply module determines that there is a risk and prohibits the conduction of the emergency drive path. Using multi-pulse detection can reduce the probability of misjudgment caused by sampling noise or transient disturbances.

[0072] In one implementation, the risk of direct current surge can be determined based on changes in both loop current and terminal voltage. If, after the energy detection signal is applied, the loop current exceeds a first preset threshold, and the change in the door lock motor terminal voltage is less than the lower limit of a preset voltage window, it indicates that the detected energy may be discharged through a low-resistance path, and the collision power module determines that there is a risk of direct current surge. The risk of reverse current surge can be determined based on the direction of reverse current and terminal voltage change. If, after the energy detection signal is removed, a reverse current flowing from the door lock motor side to the collision power module side is detected, or if an abnormal rise in the door lock motor terminal voltage occurs that is inconsistent with the direction of the energy detection signal, the collision power module determines that there is a risk of reverse current surge.

[0073] In one implementation, the identification of diagnostic conflict risk can be determined jointly by a time window and signal characteristics. During periods when the collision power supply module is not outputting drive commands to the door lock motor, it continuously collects the door lock motor terminal voltage and loop current. When the door lock motor terminal voltage exhibits periodic increases and decreases within a preset detection period, and the loop current is within a preset diagnostic current range, the collision power supply module identifies an offline diagnostic excitation signal in the normal drive path. If this offline diagnostic excitation signal persists, the collision power supply module determines that there is a diagnostic conflict risk and keeps the emergency drive path disconnected. If the offline diagnostic excitation signal disappears within a preset waiting time, the collision power supply module can re-execute the energy-limiting detection process.

[0074] In one implementation, after disabling the emergency drive path, the collision power module can perform different actions based on the risk type. If a pass-through risk is detected, the collision power module keeps the emergency isolation switch open and records the pass-through risk status. If a backflow risk is detected, the collision power module keeps the emergency drive circuit disabled and records the backflow risk status. If a diagnostic conflict risk is detected, the collision power module can delay for a preset waiting time and then re-detect, or send a diagnostic stop request to the vehicle-side electronic control unit. During the above processing, the collision power module can store the risk status in a local storage unit for subsequent fault diagnosis or accident analysis.

[0075] In one implementation, after the collision power module activates the emergency drive path, it can output an unlocking drive signal to the door lock motor via an emergency disconnect switch and an emergency drive circuit. The emergency disconnect switch remains open before activation to block energy transfer between the supercapacitor and the door lock motor. When the collision power module confirms that the conventional drive path is isolated and poses no risk, the controller controls the emergency disconnect switch to close and enables the voltage conversion circuit and the emergency drive circuit. The voltage conversion circuit converts the supercapacitor voltage into a drive voltage suitable for the door lock motor's operation, and the emergency drive circuit drives the door lock motor to perform the unlocking action according to the controller's unlocking control signal.

[0076] In one implementation, the collision power module performs closed-loop protection monitoring after the emergency drive path is activated. The controller continuously collects the door lock motor terminal voltage, door lock motor circuit current, and reverse current in the emergency drive path within a preset monitoring period. If the circuit current exceeds a preset overcurrent threshold and persists for more than a preset filtering time, it is determined that the door lock motor circuit may be stalled or short-circuited; if the door lock motor terminal voltage is lower than a preset drop threshold and persists for more than a preset filtering time, it is determined that the emergency drive voltage cannot be maintained; if the reverse current exceeds a preset reverse current threshold and persists for more than a preset filtering time, it is determined that a reverse current anomaly exists. When the above anomalies occur, the collision power module disconnects the emergency drive path and records the unlocking anomaly status.

[0077] In one embodiment, the preset threshold, preset voltage window, preset diagnostic current range, and preset filtering time can all be determined through calibration. The calibration method can be based on the rated parameters of the door lock motor, wiring harness impedance, the conduction and disconnection characteristics of the path isolating switch, the accuracy of the sampling circuit, the output capability of the voltage conversion circuit, and the operating voltage range of the supercapacitor. Different calibration parameters can be used for different vehicle models, different door lock motors, or different collision power module placements. The above parameters are not limited to fixed values; any parameters that can distinguish between normal isolation states, direct-through risk states, backflow risk states, and diagnostic conflict states are applicable to the control method of this invention.

[0078] In one embodiment, the collision power module may include a main control unit, a supercapacitor management unit, a power conversion unit, a path isolation control unit, an emergency drive unit, a sampling unit, and a communication unit. The supercapacitor management unit is used to perform supercapacitor charging and discharging status monitoring and abnormal status recording. The power conversion unit is used to charge the supercapacitor under normal conditions and convert the supercapacitor voltage into the drive voltage required by the door lock motor in collision unlocking mode. The path isolation control unit is used to control the path isolation switch in the conventional drive path. The emergency drive unit is used to control the emergency isolation switch and the door lock motor drive output in the emergency drive path. The sampling unit is used to collect the door lock motor terminal voltage, loop current, and reverse current. The communication unit is used to receive collision signals, send high-impedance control signals, and report unlocking abnormal states.

[0079] In one embodiment, the aforementioned units can be integrated within the same collision power module housing, or they can be distributed according to the vehicle architecture. For example, the supercapacitor, power conversion unit, and emergency drive unit can be located near the door lock motor to reduce the wiring harness length of the emergency drive path; the main control unit and communication unit can be located on the control circuit board of the collision power module; the path isolation switch can be located near the door lock output terminal of the vehicle-side electronic control unit, or it can be located near the door lock motor connection terminal. Regardless of the arrangement, as long as it can achieve conventional drive path isolation, emergency drive path conduction control, and pre-takeover risk detection, it falls under the embodiments of the present invention.

[0080] Please see Figure 2 The present invention also provides a vehicle door unlocking control system after a vehicle collision and power failure, for executing the above-described vehicle door unlocking control method after a vehicle collision and power failure, comprising: Main power supply; Door lock motor; The body-side controller forms a conventional drive path with the door lock motor; the body-side controller is a body-side electronic control unit. The collision power module includes a supercapacitor, a controller, a voltage conversion circuit, a sampling circuit, and an emergency drive circuit. An emergency drive path is formed between the collision power module and the door lock motor. The controller is connected to the voltage conversion circuit, the sampling circuit, and the emergency drive circuit.

[0081] Specifically, the main power supply provides power to the vehicle side controller, collision power module, and other low-voltage loads under normal vehicle conditions. The supercapacitor stores the energy required for emergency unlocking. The voltage conversion circuit charges the supercapacitor under normal conditions and converts the supercapacitor voltage into the drive voltage required by the door lock motor in collision unlocking mode. The sampling circuit collects the door lock motor terminal voltage, door lock motor circuit current, reverse current in the emergency drive path, and supercapacitor status parameters. The emergency drive circuit drives the door lock motor to perform the unlocking action after the collision power module confirms that the takeover conditions are met.

[0082] A path isolation switch is installed in the regular drive path, and an emergency isolation switch is installed in the emergency drive path. The path isolation switch is used to disconnect the electrical connection between the vehicle-side electronic control unit and the door lock motor in collision unlocking mode. The emergency isolation switch is used to connect the emergency drive path between the collision power module and the door lock motor after the collision power module confirms that the regular drive path is safe.

[0083] A path isolation switch is set in the conventional drive path, and an emergency isolation switch is set in the emergency drive path. The sampling circuit is used to collect the door lock motor terminal voltage, the door lock motor circuit current, and the reverse current in the emergency drive path. The controller is configured to allow the emergency disconnect switch to close after confirming that the normal drive path is isolated and determining, based on the door lock motor terminal voltage, door lock motor circuit current, and reverse current in the emergency drive path, that there is no risk of shoot-through, backflow, or diagnostic conflict.

[0084] In one specific implementation, the emergency disconnect switch can employ a back-to-back MOSFET structure to block reverse current flowing from the door lock motor side to the collision power module side. The path disconnect switch can employ a relay or power MOSFET structure to achieve electrical isolation of the conventional drive path in collision unlocking mode. The sampling circuit may include a terminal voltage sampling unit, a current sampling unit, and a reverse current detection unit. The controller can execute the above method steps based on the sampling results of each sampling unit.

[0085] In one simulation embodiment, to verify the feasibility of conventional drive path isolation verification and energy-limiting detection methods, an equivalent simulation model of the vehicle door lock drive circuit was established using MATLAB / Simulink R2023b simulation software developed by MathWorks. The equivalent simulation model includes a supercapacitor model, a voltage conversion circuit model, a door lock motor model, a vehicle body-side drive circuit model, a path isolation switch model, an emergency isolation switch model, a current-limiting detection branch, and terminal voltage and loop current sampling nodes. Specifically, the vehicle body-side drive circuit model simulates the door lock drive output of the vehicle body-side electronic control unit; the path isolation switch is positioned between the vehicle body-side drive circuit model and the door lock motor model; and the current-limiting detection branch applies a detection energy signal to the door lock motor model when the emergency isolation switch remains open.

[0086] In this simulation embodiment, the equivalent capacitance of the supercapacitor is set to 5F, and the initial voltage is set to 12.5V; the door lock motor adopts an equivalent model of a resistor and an inductor in series, with an equivalent resistance of 3.2Ω and an equivalent inductance of 8mH; the equivalent resistance of the wiring harness is 0.15Ω; the on-resistance of the path isolating switch is 25mΩ, and the off-resistance is 10MΩ; the current-limiting resistance of the current-limiting detection branch is 1kΩ. The detection node is equipped with an equivalent sampling capacitance of 1μF and an equivalent discharge resistance of 100kΩ. The detection energy signal adopts a pulse signal with an amplitude of 5V and a duration of 20ms. The preset voltage window for the terminal voltage change is set to 3V to 5V, the first preset threshold is set to 3mA, the second preset threshold is set to 50ms, the reverse current threshold is set to 2mA, and the sampling period for the terminal voltage and loop current is set to 1ms.

[0087] Under normal isolation conditions in the conventional drive path, after applying a detection energy signal, the terminal voltage of the detection node on the door lock motor side can change along the direction of the detection energy signal, and the amount of voltage change is within a preset voltage window; in the later part of the detection pulse, the detection current is lower than the first preset threshold. After the detection energy signal is removed, the terminal voltage decays according to the equivalent RC characteristics of the detection node, and its decay time is greater than the second preset threshold, thus determining that the conventional drive path is in a normal isolation state.

[0088] When the low-side switch on the vehicle body is abnormally turned on, the detected energy signal is discharged through the low-resistance path formed by the low-side switch. The voltage change at the door lock motor terminal is lower than the lower limit of the preset voltage window, and the detected current is in the range of about 4.5mA to 5mA and exceeds the first preset threshold. Based on this, the controller determines that there is a risk of direct connection and keeps the emergency drive path disconnected.

[0089] When an external power supply is connected to the door lock motor, the voltage at the door lock motor is clamped by the external power supply. After the detection energy signal is applied, it does not change in the preset direction, and a reverse current flowing from the door lock motor side to the collision power module side is detected; the reverse current exceeds the preset reverse current threshold. Based on this, the controller determines that there is a risk of backflow and prohibits the emergency drive path from conducting.

[0090] The above simulation analysis shows that by jointly judging the change in voltage at the door lock motor terminal and the loop current during the application of the detection energy signal, as well as the voltage decay characteristics after the detection signal is removed, the normal isolation state, the direct-through risk state, and the backflow risk state of the conventional drive path can be distinguished, and the conduction state of the emergency isolation switch can be controlled accordingly.

[0091] This description is only intended to illustrate the technical solutions of this application and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for controlling door unlocking after a vehicle collision and power failure, the vehicle comprising a vehicle-side electronic control unit, a collision power module, a door lock motor, a main power supply, and a supercapacitor, wherein the vehicle-side electronic control unit and the door lock motor form a conventional drive path, and the collision power module and the door lock motor form an emergency drive path, characterized in that... Includes the following steps: S1: Under normal conditions, the collision power module keeps the emergency drive path disconnected and charges and monitors the status of the supercapacitor. S2: When the collision signal is valid and the main power supply is abnormal, the collision power module enters the collision unlocking mode; S3: In the collision unlocking mode, the collision power module controls the conventional drive path to enter the isolation state, including: outputting a high-resistance control command to the vehicle-side electronic control unit so that the door lock drive output terminal of the vehicle-side electronic control unit enters the high-resistance state; and controlling the path isolation switch set in the conventional drive path to open. S4: When the emergency drive path is kept disconnected, the collision power module collects the voltage at the door lock motor terminal and the circuit current, and determines whether there is a risk of direct connection, backflow or diagnostic conflict in the normal drive path through the energy limiting detection method. The energy limiting detection method is to apply a detection energy signal lower than the drive action threshold to the circuit where the door lock motor is located. S5: Determine whether the aforementioned risk exists. If the risk does not exist, the collision power module activates the emergency drive path and the supercapacitor supplies power to the door lock motor to unlock it. If the risk exists, the activation of the emergency drive path is prohibited.

2. The vehicle door unlocking control method after power failure following a vehicle collision as described in claim 1, characterized in that: In step S2, the main power supply abnormality is determined based on at least one of the main power supply voltage being lower than a preset power failure threshold and the main power supply connection being interrupted. When communication between the vehicle-side electronic control unit and the collision power module is interrupted, or when the periodic status signal of the vehicle-side electronic control unit is lost, the collision power module will determine the status of the normal drive path as unconfirmable.

3. The vehicle door unlocking control method after power failure following a vehicle collision as described in claim 1, characterized in that: In step S3, controlling the conventional drive path to enter the isolation state includes the following steps: S31: Send a high-impedance control signal to the vehicle-side electronic control unit to cause the door lock drive output of the vehicle-side electronic control unit to enter a high-impedance state; S32: Controls the path isolation switch set in the normal drive path to disconnect, so as to form electrical isolation between the vehicle-side electronic control unit and the door lock motor; S33: Based on the disconnection feedback signal of the path isolation switch and the change in the voltage at the door lock motor terminal, confirm that the conventional drive path has entered the isolation state.

4. The vehicle door unlocking control method after power failure following a vehicle collision as described in claim 1, characterized in that: In step S4, the door lock motor terminal voltage includes the voltage of at least one terminal of the door lock motor relative to the vehicle body ground and the differential voltage between the two ends of the door lock motor. The circuit current includes the drive current flowing through the door lock motor and the reverse current flowing from the door lock motor side to the collision power module side.

5. The vehicle door unlocking control method after power failure following a vehicle collision as described in claim 1, characterized in that: In step S4, the energy-limited detection method includes the following steps: S41: With the emergency drive path kept disconnected, the voltage at the door lock motor terminal is collected as the reference voltage. S42: Apply a detection energy signal to the circuit where the door lock motor is located through the current limiting detection branch, wherein the energy of the detection energy signal is lower than the minimum energy required to drive the door lock motor to produce an action; S43: During the application of the detection energy signal, the voltage change at the door lock motor terminal and the loop current are collected; S44: After the detected energy signal is withdrawn, the voltage decay time at the door lock motor terminal is collected; S45: When the voltage change at the door lock motor terminal is within a preset voltage window, the circuit current is less than a first preset threshold, and the voltage decay time at the door lock motor terminal is greater than a second preset threshold, it is determined that there is no risk of direct connection or backflow in the conventional drive path.

6. The vehicle door unlocking control method after power failure following a vehicle collision as described in claim 1, characterized in that: In step S4, the assessment of conflict risk includes: During the period when the collision power module does not send a drive command to the door lock motor, it detects whether the voltage at the door lock motor terminal changes periodically within a preset detection period, and detects whether the circuit current is within a preset diagnostic current range. When the voltage at the door lock motor terminal changes periodically and the circuit current is within the preset diagnostic current range, an offline diagnostic excitation signal is detected in the conventional drive path, and a diagnostic conflict risk is determined.

7. The vehicle door unlocking control method after power failure following a vehicle collision as described in claim 1, characterized in that: In step S5, after the collision power module turns on the emergency drive path, it continuously collects the door lock motor terminal voltage and circuit current within a preset monitoring period. When at least one of the following abnormal conditions is met and continues for more than the preset filtering time: the circuit current is greater than the preset overcurrent threshold, the door lock motor terminal voltage is lower than the preset drop threshold, or the reverse current is greater than the preset reverse current threshold, the emergency drive path is disconnected and the unlocking abnormal status is recorded.

8. A vehicle door unlocking control system after a vehicle collision and power failure, used to execute the vehicle door unlocking control method after a vehicle collision and power failure as described in any one of claims 1 to 7, characterized in that, include: Main power supply; Door lock motor; A vehicle-side controller forms a conventional drive path with the door lock motor; the vehicle-side controller is a vehicle-side electronic control unit. The collision power module includes a supercapacitor, a controller, a voltage conversion circuit, a sampling circuit, and an emergency drive circuit. The collision power module forms an emergency drive path with the door lock motor. The controller is connected to the voltage conversion circuit, the sampling circuit, and the emergency drive circuit, respectively.

9. The vehicle door unlocking control system after a vehicle collision power failure according to claim 8, characterized in that, The conventional drive path is equipped with a path isolation switch, the emergency drive path is equipped with an emergency isolation switch, and the sampling circuit is used to collect the door lock motor terminal voltage, the door lock motor circuit current, and the reverse current in the emergency drive path. The controller is configured to allow the emergency isolation switch to close after confirming that the normal drive path is in an isolated state and determining, based on the door lock motor terminal voltage, door lock motor circuit current, and reverse current in the emergency drive path, that there is no risk of shoot-through, backflow, or diagnostic conflict.

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