Independently controlled automobile power blocking device and blocking method

Abstract

The present application provides an independently controlled vehicle power blocking device and method, relating to the field of vehicle power blocking technology. The device comprises: a main control chip with a built-in decision-making unit; an independent ignition control chip connected to the main control chip via a hardware isolation channel, and a built-in verification unit; a hardware interface expansion module supporting at least one of the CAN bus, linear communication, and Line protocols, for multi-source signal interaction with the vehicle's battery management system, vehicle control system, or external detection equipment; a decision-making unit configured to generate a primary decision signal based on the multi-source signals; and an independent ignition control chip configured to drive a power cutoff module to execute a power cutoff action when the primary decision signal indicates that the vehicle power needs to be blocked and the decision verification passes. This vehicle power blocking device is independent of the ACU, possesses the ability to make autonomous decisions based on multi-source data, and supports dynamic safety regulation to address the response delays, single-point failures, and malfunctions of traditional solutions.

Description

Technical Field

[0001] The present application relates to the technical field of automobile power blocking technology, and in particular to an independently controlled automobile power blocking device and a blocking method. Background Art

[0002] Traditional automotive power blocking devices (PBDs) rely entirely on instructions from the vehicle control unit (ACU) to execute power-off operations. For example, application number 202411285956.0, titled "A New Energy Vehicle Powertrain Collision Power-Off Control Method and Vehicle," discloses its workflow: the ACU detects a fault (such as a collision or battery overvoltage) and then issues a command, causing the PBD to passively execute the power-off operation.

[0003] This workflow has the following limitations: a high risk of single-point failure. If the ACU fails or is attacked, the traditional PBD loses its emergency response capability. The traditional solution only receives single-channel instructions from the ACU. In addition, there is a lack of cross-validation of multi-source data and a high misjudgment rate. These all lead to poor reliability in blocking the vehicle power supply. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, the present application aims to provide an independently controlled automobile power blocking device and blocking method to improve the blocking reliability of the automobile power supply;

[0005] In a first aspect, the present application provides an independently controlled automobile power blocking device, comprising:

[0006] A main control chip, wherein the main control chip has a built-in decision-making unit;

[0007] An independent ignition control chip, the independent ignition control chip is connected to the main control chip via a hardware isolation channel, and the independent ignition control chip has a built-in verification unit;

[0008] A hardware interface expansion module, the hardware interface expansion module supporting at least one of CAN bus, linear communication, and Line protocol, for multi-source signal interaction with a vehicle battery management system, a vehicle control system, or external detection equipment;

[0009] The decision unit is configured to generate a primary decision signal based on the multi-source signal; the independent ignition control chip is configured to drive the power cut-off module to perform a power cut-off action when the primary decision signal indicates that the vehicle power supply needs to be blocked and the decision verification passes.

[0010] According to the technical solution provided in this application, the hardware interface expansion module includes a voltage sampling unit for voltage signals, a reconstruction unit for temperature field distribution matrix, and a feature extraction unit for electrolyte gas concentration spectrum.

[0011] According to the technical solution provided in the present application, the verification unit is configured to perform decision verification on the primary decision signal, and the decision verification includes checking the protocol integrity of the data source of the multi-source signal, verifying the physical rationality of the multi-source signal, and confirming the timing consistency between each of the multi-source signals.

[0012] According to the technical solution provided in this application, the power cut-off module includes a mechanical explosion-type fuse and an electronic fuse backup unit. The electronic fuse backup unit is configured to forcibly disconnect the high-voltage circuit through an IGBT device when the mechanical explosion-type fuse fails.

[0013] According to the technical solution provided in this application, the hardware isolation channel is a dual verification circuit, including an optical isolation channel composed of a photoelectric coupler and an electromagnetic isolation channel composed of a magnetic isolation chip. The two channels transmit the primary decision signal in parallel, and the independent ignition control chip starts the verification unit only when the signals transmitted by the two channels are logically consistent.

[0014] In a second aspect, the present application proposes an independently controlled automobile power blocking method, which is implemented based on the independently controlled automobile power blocking device as described above, and includes the following steps:

[0015] Real-time and parallel acquisition of the voltage gradient time series, temperature field distribution matrix, and electrolyte gas concentration spectrum of the vehicle battery management system;

[0016] Calculate the change rate weight in the time dimension and the distribution correlation weight in the spatial dimension;

[0017] generating an adaptive safety threshold based on the change rate weight and the distribution correlation weight, and obtaining a fault probability when the voltage gradient is greater than the corresponding adaptive safety threshold for three consecutive sampling periods;

[0018] Based on the failure probability, a comprehensive risk factor is generated by combining the proportion of temperature field abnormal distribution areas and the gas concentration mutation index;

[0019] If the comprehensive risk factor is greater than a first preset threshold, a primary decision signal is triggered after the decision verification by the verification unit passes;

[0020] If the primary decision signal indicates that the vehicle power supply needs to be cut off, the power cut-off module is driven to execute a power cut-off action.

[0021] According to the technical solution provided by this application, the primary decision signal includes:

[0022] When the comprehensive risk factor is within a first preset range, the primary decision signal represents an early warning to reduce charging power;

[0023] When the comprehensive risk factor is within a second preset range, the primary decision signal indicates that the vehicle power supply needs to be blocked;

[0024] When the comprehensive risk factor is greater than or equal to a second preset threshold, the primary decision signal indicates that cell-level directional detonation is required;

[0025] The lower limit value of the first preset interval is the first preset threshold value, the upper limit value of the first preset interval is the lower limit value of the second preset interval, the upper limit value of the second preset interval is the second preset threshold value, and the second preset threshold value is greater than the first preset threshold value.

[0026] According to the technical solution provided by this application, before generating the adaptive safety threshold based on the change rate weight and the distribution correlation weight, the following steps are included:

[0027] Obtain battery health status parameters in real time and calculate aging compensation coefficient;

[0028] Generating an adaptive safety threshold based on the change rate weight and the distribution correlation weight comprises the following steps:

[0029] If the battery health status parameter is greater than a third preset threshold, generating an adaptive safety threshold based on the change rate weight and the distribution correlation weight;

[0030] After obtaining the battery health status parameters in real time and calculating the aging compensation coefficient, the following steps are also included:

[0031] If the battery health status parameter is less than or equal to the third preset threshold, an adaptive safety threshold is generated based on the change rate weight, the distribution correlation weight, and the aging compensation coefficient.

[0032] According to the technical solution provided by the present application, before generating a comprehensive risk coefficient based on the failure probability, combined with the proportion of abnormal temperature field distribution areas and the gas concentration mutation index, the following steps are also included:

[0033] Real-time monitoring of the cell voltage difference between every two adjacent cells;

[0034] The method of generating a comprehensive risk factor based on the failure probability and combining the temperature field abnormal distribution area ratio and the gas concentration mutation index includes the following steps:

[0035] If the voltage differences of all the battery cells are less than a fourth preset threshold, a comprehensive risk factor is generated based on the failure probability, the proportion of abnormal temperature field distribution areas, and the gas concentration mutation index;

[0036] After the real-time monitoring of the cell voltage difference between every two adjacent cells, the following steps are also included:

[0037] If at least one of the battery cell voltage differences is greater than or equal to a fourth preset threshold, the position corresponding to the battery cell voltage difference is taken as the abnormal battery cell position;

[0038] If the temperature gradient of the local hot spot area obtained through the temperature field distribution matrix is ​​greater than the fifth preset threshold, and the local hot spot area coincides with the position of the abnormal battery cell, a primary decision signal indicating that battery cell-level directional detonation is required is triggered.

[0039] According to the technical solution provided by this application, the driving power cut-off module performs the power cut-off action, including the following steps:

[0040] Drive the mechanical burst fuse to perform mechanical blocking, and collect the residual voltage after mechanical blocking;

[0041] If the residual voltage after blocking is in the first-level failure range, the electronic fuse backup unit is activated to forcibly disconnect the high-voltage circuit through the IGBT device and inject reverse current into the adjacent module to offset the residual potential.

[0042] Compared with the existing technology, the beneficial effects of the present application are as follows: the present application realizes decision-making-execution separation through a dual-chip architecture (MCU + ignition chip), the main control chip is responsible for multi-source data analysis, and the ignition chip implements hardware-level verification, reducing the false trigger rate and improving safety performance; at the same time, hardware isolation channels and parallel data processing effectively overcome the power-off action triggering delay problem and curb the spread of battery thermal runaway; in addition, the decision unit can adapt to programmable logic thresholds, support real-time adjustment of safety thresholds based on parameters such as battery SOH (health status) and ambient temperature, and optimize dynamic adaptability; through the hardware interface expansion module, it is compatible with multi-source instructions such as BUD, ACU, and user terminals. When the ACU fails, power off can still be triggered through BUD direct connection or user APP, supporting scenario compatibility expansion. At this point, the vehicle power blocking device can be independent of the ACU, have the ability to make independent decisions based on multi-source data, and support dynamic safety regulation to solve the response delay, single point failure and false operation problems of traditional solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is a schematic diagram of the structure of the independently controlled automobile power blocking device provided in this application;

[0044] Figure 2 This is a flowchart of the steps of the independently controlled automobile power blocking method provided in this application. DETAILED DESCRIPTION

[0045] The present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the relevant invention and are not intended to limit the invention. It should also be noted that, for ease of description, only portions relevant to the invention are shown in the accompanying drawings.

[0046] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0047] Example 1

[0048] As mentioned in the background technology, in order to solve the problems in the prior art, this application proposes an independent control type automobile power blocking device and a blocking device, such as Figure 1 Shown, including:

[0049] A main control chip, wherein the main control chip has a built-in decision-making unit;

[0050] An independent ignition control chip, the independent ignition control chip is connected to the main control chip via a hardware isolation channel, and the independent ignition control chip has a built-in verification unit;

[0051] A hardware interface expansion module, the hardware interface expansion module supporting at least one of CAN bus, linear communication, and Line protocol, for multi-source signal interaction with a vehicle battery management system, a vehicle control system, or external detection equipment;

[0052] The decision unit is configured to generate a primary decision signal based on the multi-source signal; the independent ignition control chip is configured to drive the power cut-off module to perform a power cut-off action when the primary decision signal indicates that the vehicle power supply needs to be blocked and the decision verification passes.

[0053] Furthermore, the hardware isolation channel is a dual verification circuit, including an optical isolation channel composed of a photoelectric coupler and an electromagnetic isolation channel composed of a magnetic isolation chip. The two channels transmit the primary decision signal in parallel, and the independent ignition control chip starts the verification unit only when the signals transmitted by the two channels are logically consistent.

[0054] Optionally, the main control chip utilizes a Cortex-M7 core MCU running FreeRTOS. The decision-making unit is an algorithm module based on an LSTM neural network, with input dimensions consisting of a spatiotemporal matrix of voltage, temperature, and gas concentration. The independent ignition control chip utilizes an ASIL D-rated safety chip (such as the Infineon Aurix TC397), and the verification unit has a built-in physical rule library (e.g., temperature change rate ≤ 50°C / s). Hardware interface expansion modules include a CAN bus interface, which connects to the vehicle network via a TJA1042 transceiver; a Linear communication interface, which utilizes the RS-485 physical layer and directly connects to the BUD's ADC sampling unit; and a Line protocol interface, which implements Manchester encoding and decoding via optocoupler isolation circuits. The hardware isolation channel between the main control chip and the ignition chip is dually isolated using the ADuM3160 (magnetic isolation) and the HCPL-0723 (optical isolation), with a transmission rate of 10 Mbps. Multi-source signal interaction includes simultaneous data processing of at least two heterogeneous protocols (e.g., CAN + Linear).

[0055] In a preferred embodiment, the hardware interface expansion module includes a voltage sampling unit for voltage signals, a temperature field distribution matrix reconstruction unit, and a feature extraction unit for electrolyte gas concentration spectrum.

[0056] Specifically, a 64-channel PT100 thermocouple array is used to cover the upper and lower surfaces of each battery module in a 5×5 matrix (32 sensors per surface), and auxiliary sensors are set at the module gaps (2 per gap, a total of 16). The spacing between the module surface sensors is ≤2cm to ensure that adjacent sensors can cross-verify in the event of a single point failure. Module gap: Flexible thermocouple tapes are inserted between adjacent modules with a spacing of ≤1cm to detect the heat conduction path. The reconstruction unit of the temperature field distribution matrix receives the temperature space-time matrix composed of the real-time readings of all temperature sensors;

[0057] Specifically, nine TGS8100 sensors are deployed inside the battery pack to form a 3×3 monitoring grid: four sensors are deployed in the module gaps (spacing ≤ 5 cm), and five sensors are deployed in the top space (center + four corners). The readings of these nine sensors form a gas space-time matrix. The electrolyte gas concentration spectrum mainly detects the gas concentrations of H2, CO, and C2H4. Feature extraction: Wavelet packet transform is performed on the sensor response curve, and the 3rd-5th order coefficients are extracted as feature vectors.

[0058] Specifically, the voltage sensor array layout is as follows: each battery module is configured with 24 voltage sampling points, evenly distributed in a 6×4 matrix (spacing ≤ 3 cm), covering the positive / negative tabs and the center area of ​​the module, obtaining 24 voltage signals, generating a data frame every 10 ms, and obtaining a voltage space-time matrix.

[0059] In a preferred embodiment, the verification unit is configured to perform decision verification on the primary decision signal, and the decision verification includes checking the protocol integrity of the data source of the multi-source signal, verifying the physical rationality of the multi-source signal, and confirming the timing consistency between each of the multi-source signals.

[0060] Specifically, the protocol integrity check includes verifying the packet header identifier (such as CAN ID 0x18FFA1B2) and payload length, as well as verifying the digital signature (ECDSA algorithm, key length 256 bits). Physical rationality verification includes checking the temperature signal mutation rate: if ΔT / Δt>100°C / s, it is judged to be abnormal; and voltage-gas concentration correlation check: the theoretical gas concentration is calculated according to the Nernst equation, and an abnormality is considered if the deviation from the measured value is >20%. Timing consistency confirmation (the quantitative standard is that the time difference between each signal must be less than 1ms) includes multi-source signal timestamp alignment: μs-level synchronization is achieved based on the PTP protocol, and causal logic verification: the temperature rise must precede the gas concentration mutation (delay ≤ 50ms).

[0061] This embodiment can resolve false triggering caused by tampering of sensor data (such as forged temperature signals) and decision conflicts caused by differences in multi-source signal transmission delays.

[0062] In a preferred embodiment, the power cut-off module includes a mechanical burst fuse and an electronic fuse backup unit, and the electronic fuse backup unit is configured to forcibly disconnect the high-voltage circuit through an IGBT device when the mechanical burst fuse fails.

[0063] Specifically, the mechanical burst fuse uses a powder-driven copper blade to cut the busbar, with an operating time of ≤0.5ms. The burst pressure is 50MPa and is triggered by a piezoelectric ceramic sensor. The electronic fuse backup unit uses the Infineon FF600R12ME4 IGBT module with a rated voltage of 1200V. The driver circuit uses gate charge pump technology, with a turn-off time of ≤10μs. Fuse failure is determined by a residual voltage >60V after the mechanical burst fuse has blown.

[0064] Example 2

[0065] This embodiment proposes an independent control type automobile power blocking method, which is implemented based on the independent control type automobile power blocking device as described in Example 1. Figure 2 As shown, the following steps are included:

[0066] S1. Real-time and parallel acquisition of the voltage gradient time series, temperature field distribution matrix, and electrolyte gas concentration spectrum of the vehicle battery management system;

[0067] Specifically, the voltage gradient time series is obtained by calculating dV / dt through a sliding window (length 100 ms) with a window step of 10 ms; the temperature field distribution matrix is ​​obtained by updating it every 50 ms, and the gas concentration spectrum: the sampling rate per channel is 500 Hz.

[0068] S2. Calculate the change rate weight in the time dimension and the distribution correlation weight in the spatial dimension;

[0069] Specifically, through the formula Get the change rate weight in the time dimension, where W t It represents the rate of change weight in the time dimension, which is used to quantify the urgency of the voltage gradient change. dV / dt represents the voltage gradient (the rate of change of voltage over time), which is calculated by the above sliding window. k is the slope adjustment coefficient of the Sigmoid function, which controls the sensitivity of the weight to the change of the voltage gradient. k=0.1; through the formula ,in, W s represents the distribution correlation weight in the spatial dimension, It represents the difference between the temperature of the pixel at row i and column j in the temperature field matrix and the reference temperature. N The total number of pixels in the abnormal area (i.e. the number of pixels judged to be "abnormal"), T avg Represents the average temperature of the temperature field (global or local background).

[0070] S3. Generate an adaptive safety threshold based on the change rate weight and the distribution correlation weight, and obtain a fault probability when the voltage gradient is greater than the corresponding adaptive safety threshold for three consecutive sampling periods;

[0071] Specifically, through the formula Get the adaptive security threshold, where V base According to the battery type setting (such as ternary lithium battery is set to 4.2V), each 10ms is a sampling cycle, and the time range of three consecutive sampling cycles is 30ms.

[0072] Specifically, the Bayesian conditional probability is used to calculate the single failure probability of each single sampling period, and a weight is assigned to each exceeding sampling period to reflect its risk contribution. The failure probability is then obtained based on the single failure probability and the assigned weight of each exceeding sampling period.

[0073] For example, the historical database records 1000 voltage gradient exceeding events, 200 of which eventually lead to failures (N fault =200,N total=1000), the current three consecutive cycles exceed the standard value: Cycle 1: dV1 / dt = 0.6V / s, Vth(t1) = 0.5V / s; Cycle 2: dV2 / dt = 0.7V / s, Vth(t2) ​​= 0.55V / s; Cycle 3: dV3 / dt = 0.8V / s, Vth(t3) = 0.6V / s. Single cycle probability calculation: Single failure probability in cycle 1 Similarly, the probability of a single failure in period 2 is 0.253, and the probability of a single failure in period 3 is 0.291. The time weight is calculated as follows: the distribution weight of period 1 =0.606, the assigned weight of cycle 2 is 0.779, and the assigned weight of cycle 3 is 0.882. The normalized weights are: cycle 1 = 0.267, cycle 2 = 0.343, cycle 3 = 0.390, and the final failure probability is 0.259.

[0074] S4. Based on the failure probability, a comprehensive risk factor is generated by combining the proportion of abnormal temperature field distribution areas and the gas concentration mutation index;

[0075] Specifically, the temperature field anomaly distribution area is defined as a continuous 3×3 pixel block with a temperature difference greater than 15°C. The gas concentration mutation index is calculated as the logarithmic rate of change of the current concentration / baseline concentration, where the baseline concentration is determined by the average of 24 consecutive hours of sampling while the battery is in a static state. The comprehensive risk factor is a normalized risk assessment value (ranging from 0 to 1) that quantifies the overall safety risk level of the battery system. It integrates the anomaly characteristics of multi-source heterogeneous data (voltage, temperature, and gas concentration) to generate a single decision metric. The comprehensive risk factor is 0.6A + 0.3B + 0.1C, where A represents the voltage fault probability, calculated based on historical statistics of voltage gradient violations (Bayesian probability model). B represents the proportion of the temperature field anomaly distribution area, which is the ratio of the area of ​​continuous 3×3 pixel blocks with a temperature difference greater than 15°C to the total monitored area. C represents the gas concentration mutation index. The basis for weight distribution is that the voltage failure probability (60%) has the highest weight, because voltage mutation is the most direct precursor to thermal runaway; temperature anomaly (30%) reflects the risk of thermal diffusion; gas concentration (10%) is an early chemical byproduct indicator with low sensitivity but complementary.

[0076] S5. If the comprehensive risk factor is greater than a first preset threshold, a primary decision signal is triggered after the verification unit passes the decision verification;

[0077] S6. If the primary decision signal indicates that the vehicle power supply needs to be blocked, the power cut-off module is driven to execute a power cut-off action.

[0078] Furthermore, the primary decision signal includes:

[0079] When the comprehensive risk factor is within a first preset range, the primary decision signal represents an early warning to reduce charging power;

[0080] When the comprehensive risk factor is within a second preset range, the primary decision signal indicates that the vehicle power supply needs to be blocked;

[0081] When the comprehensive risk factor is greater than or equal to a second preset threshold, the primary decision signal indicates that cell-level directional detonation is required;

[0082] The lower limit value of the first preset interval is the first preset threshold value, the upper limit value of the first preset interval is the lower limit value of the second preset interval, the upper limit value of the second preset interval is the second preset threshold value, and the second preset threshold value is greater than the first preset threshold value.

[0083] Specifically, the first preset threshold is the safety baseline for the comprehensive risk factor, used to distinguish between "normal state" and "warning state." Below this threshold, the battery status is stable, and no active intervention is required, avoiding frequent false triggering and degrading the user experience. The second preset threshold is the emergency action line for the comprehensive risk factor, used to distinguish between "power off state" and "detonation state." Above this threshold, the most stringent measures (such as cell-level targeted detonation) must be immediately implemented to curb the chain reaction.

[0084] Optionally, the first preset threshold is 0.5, and the second preset threshold is 0.9. The primary decision signal is to divide the battery safety status into four levels (normal, warning, power off, and detonation), corresponding to different control responses. Normal state (coefficient <0.5): Maintain routine monitoring and collect data every 100ms. Warning state (0.5≤coefficient <0.7): Start the thermal management system, reduce the charging power to 50% of the rated value, and increase the data sampling frequency to 10ms. The car power supply needs to be blocked (0.7≤coefficient <0.9): Trigger the main relay to disconnect, and start the backup power supply to maintain the operation of critical systems. Detonation state (coefficient ≥0.9): Send a 12V trigger signal to the EBF device of the corresponding battery cell through the ASIC chip.

[0085] In a preferred embodiment, before generating the adaptive safety threshold based on the change rate weight and the distribution correlation weight, the following steps are included:

[0086] Obtain battery health status parameters in real time and calculate aging compensation coefficient;

[0087] Specifically, the state of health parameter (SOH) of the battery characterizes the percentage of the current capacity of the battery relative to the initial capacity; the aging compensation coefficient (β) is a scaling factor used to correct the safety threshold to adapt to the aging state of the battery. When SOH > 85%, the aging compensation coefficient is 1 (i.e., no compensation is required). When 70% < SOH ≤ 85%, the aging compensation coefficient is , and when SOH ≤ 70%, the aging compensation coefficient is 0.5; the calculation formula integrates a coulomb meter (such as TI BQ34Z100) in the BMS to statistically accumulate the charge and discharge power. When the cumulative cycle capacity reaches 85% of C initial, it is determined that SOH = 85%;

[0088] Generating an adaptive safety threshold based on the change rate weight and the distribution correlation weight includes the following steps:

[0089] If the state of health parameter of the battery is greater than the third preset threshold, an adaptive safety threshold is generated based on the change rate weight and the distribution correlation weight;

[0090] After obtaining the state of health parameter of the battery in real time and calculating the aging compensation coefficient, the following steps are further included:

[0091] If the state of health parameter of the battery is less than or equal to the third preset threshold, an adaptive safety threshold is generated based on the change rate weight, the distribution correlation weight, and the aging compensation coefficient.

[0092] Specifically, the adaptive safety threshold is a dynamically adjusted voltage gradient threshold. After every 24 hours or each charge and discharge cycle, the state of health parameter (SOH value) of the battery is updated through the BMS; the third preset threshold is set to 85%. When the SOH value > 85%, the adaptive safety threshold is obtained through the formula When SOH ≤ 85%, the compensation logic is activated, and the adaptive safety threshold is obtained through the formula to obtain the adaptive safety threshold.

[0093] In a preferred embodiment, before generating a comprehensive hazard coefficient based on the failure probability, in combination with the proportion of the abnormal distribution area of the temperature field and the gas concentration mutation index, the following steps are further included:

[0094] Real-time monitor the voltage difference between every two adjacent battery cells;

[0095] Specifically, the voltage difference between battery cells refers to the absolute value difference of the voltages between adjacent battery cells. Use an AD7779 ADC chip (24-bit resolution, 8-channel synchronous sampling) to collect the voltage of the battery cells once every 1 ms. Establish a battery cell topology relationship matrix in the MCU to automatically identify adjacent battery cell pairs, and calculate the voltage difference between battery cells in real time through a hardware subtractor;

[0096] The method of generating a comprehensive risk factor based on the failure probability and combining the temperature field abnormal distribution area ratio and the gas concentration mutation index includes the following steps:

[0097] If the voltage differences of all the battery cells are less than a fourth preset threshold, a comprehensive risk factor is generated based on the failure probability, the proportion of abnormal temperature field distribution areas, and the gas concentration mutation index;

[0098] Specifically, the fourth preset threshold is set based on the battery type: 0.3V for ternary lithium batteries and 0.2V for lithium iron phosphate batteries. A voltage difference across all cells below the fourth preset threshold indicates the absence of the following issues: cell aging or damage: differences in internal resistance leading to uneven charging and discharging; partial short circuit: a short circuit within a cell causing a sudden voltage drop; or connection failure: poor contact at a busbar or welding point causing an abnormal voltage drop.

[0099] After the real-time monitoring of the cell voltage difference between every two adjacent cells, the following steps are also included:

[0100] If at least one of the battery cell voltage differences is greater than or equal to a fourth preset threshold, the position corresponding to the battery cell voltage difference is taken as the abnormal battery cell position;

[0101] If the temperature gradient of the local hot spot area obtained through the temperature field distribution matrix is ​​greater than the fifth preset threshold, and the local hot spot area coincides with the position of the abnormal battery cell, a primary decision signal indicating that battery cell-level directional detonation is required is triggered.

[0102] Specifically, if at least one of the cell voltage differences is greater than or equal to the fourth preset threshold, indicating at least one of the aforementioned issues, a determination is made as to whether to trigger cell-level directional detonation for safety reasons. A local hotspot is defined as a continuous 3×3 pixel area in the temperature field matrix with a single-point temperature gradient of 12°C / cm². A FLIR A315 infrared camera (320×240 resolution) with a spatial resolution of 1mm / pixel is used to identify the coordinates of the hotspot area using an image processing algorithm (OpenCV contour detection). The location of the abnormal cell voltage difference (e.g., cell 5) is mapped to thermal imaging coordinates. A match is determined if the coordinates of the hotspot center are ≤2mm away from the location of the tab of cell 5. The fifth preset threshold is a temperature gradient of 10°C / cm² (set based on battery thermal runaway experimental data: when the local temperature gradient exceeds 10°C / cm², the probability of a cell short circuit exceeds 95%).

[0103] In a preferred embodiment, the driving power cut-off module performs the power cut-off action, comprising the following steps:

[0104] Drive the mechanical burst fuse to perform mechanical blocking, and collect the residual voltage after mechanical blocking;

[0105] If the residual voltage after blocking is in the first-level failure range, the electronic fuse backup unit is activated to forcibly disconnect the high-voltage circuit through the IGBT device and inject reverse current into the adjacent module to offset the residual potential.

[0106] Specifically, the first-level failure interval refers to the range of 5-60V residual voltage after mechanical melting. The first-level failure interval is 5-60V. If the residual voltage after blocking is in the first-level failure interval, the electronic fuse backup unit needs to be activated. The second-level failure interval is the residual voltage ≥60V. When the residual voltage is between 5-60V, a reverse current is injected into the adjacent module based on the H-bridge circuit: using CREE CAS300M12BM2 SiC module, the control logic is a PID regulator that dynamically adjusts the reverse current amplitude according to the residual voltage value; when the residual voltage is ≥60V and the temperature is greater than 150℃, the residual voltage after blocking is in the second-level failure interval, and the injection valve is opened for liquid nitrogen spray cooling.

[0107] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression, there are objectively infinite specific structures. For ordinary technicians in this technical field, without departing from the principles of the present invention, they can also make several improvements, modifications or changes, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. An independently controlled automobile power blocking device, characterized in that: include: A main control chip, wherein the main control chip has a built-in decision-making unit; An independent ignition control chip, the independent ignition control chip is connected to the main control chip via a hardware isolation channel, and the independent ignition control chip has a built-in verification unit; A hardware interface expansion module, the hardware interface expansion module supporting at least one of CAN bus, linear communication, and Line protocol, for multi-source signal interaction with a vehicle battery management system, a vehicle control system, or external detection equipment; Wherein, the decision unit is configured to generate a primary decision signal according to the multi-source signals; The independent ignition control chip is configured to drive the power cut-off module to execute a power cut-off action when the primary decision signal indicates that the vehicle power supply needs to be blocked and the decision verification passes; The hardware isolation channel is a dual verification circuit, including an optical isolation channel composed of a photoelectric coupler and an electromagnetic isolation channel composed of a magnetic isolation chip. The two channels transmit the primary decision signal in parallel, and the independent ignition control chip starts the verification unit only when the signals transmitted by the two channels are logically consistent.

2. The independently controlled automobile power supply blocking device according to claim 1, characterized in that: The hardware interface expansion module includes a voltage sampling unit for voltage signals, a temperature field distribution matrix reconstruction unit, and a feature extraction unit for electrolyte gas concentration spectrum.

3. The independently controlled automobile power supply blocking device according to claim 1, characterized in that: The verification unit is configured to perform decision verification on the primary decision signal, wherein the decision verification includes checking the protocol integrity of the data source of the multi-source signal, verifying the physical rationality of the multi-source signal, and confirming the timing consistency between each of the multi-source signals.

4. The independently controlled automobile power supply blocking device according to claim 1, characterized in that: The power cut-off module includes a mechanical explosion-type fuse and an electronic fuse backup unit. The electronic fuse backup unit is configured to forcibly disconnect the high-voltage circuit through an IGBT device when the mechanical explosion-type fuse fails.

5. A method for independently controlling a vehicle power supply blocking, implemented based on the independently controlling a vehicle power supply blocking device according to any one of claims 1 to 4, characterized in that: The following steps are involved: Real-time and parallel acquisition of the voltage gradient time series, temperature field distribution matrix, and electrolyte gas concentration spectrum of the vehicle battery management system; Calculate the change rate weight in the time dimension and the distribution correlation weight in the spatial dimension; generating an adaptive safety threshold based on the change rate weight and the distribution correlation weight, and obtaining a fault probability when the voltage gradient is greater than the corresponding adaptive safety threshold for three consecutive sampling periods; Based on the failure probability, a comprehensive risk factor is generated by combining the proportion of temperature field abnormal distribution areas and the gas concentration mutation index; If the comprehensive risk factor is greater than a first preset threshold, a primary decision signal is triggered after the decision verification by the verification unit passes; If the primary decision signal indicates that the vehicle power supply needs to be cut off, the power cut-off module is driven to execute a power cut-off action.

6. The independently controlled automobile power blocking method according to claim 5, characterized in that: The primary decision signal includes: When the comprehensive risk factor is within a first preset range, the primary decision signal represents an early warning to reduce charging power; When the comprehensive risk factor is within a second preset range, the primary decision signal indicates that the vehicle power supply needs to be blocked; When the comprehensive risk factor is greater than or equal to a second preset threshold, the primary decision signal indicates that cell-level directional detonation is required; The lower limit value of the first preset interval is the first preset threshold value, the upper limit value of the first preset interval is the lower limit value of the second preset interval, the upper limit value of the second preset interval is the second preset threshold value, and the second preset threshold value is greater than the first preset threshold value.

7. The independently controlled automobile power blocking method according to claim 5, characterized in that: Before generating the adaptive safety threshold based on the change rate weight and the distribution correlation weight, the following steps are included: Obtain battery health status parameters in real time and calculate aging compensation coefficient; Generating an adaptive safety threshold based on the change rate weight and the distribution correlation weight comprises the following steps: If the battery health status parameter is greater than a third preset threshold, generating an adaptive safety threshold based on the change rate weight and the distribution correlation weight; After obtaining the battery health status parameters in real time and calculating the aging compensation coefficient, the following steps are also included: If the battery health status parameter is less than or equal to the third preset threshold, an adaptive safety threshold is generated based on the change rate weight, the distribution correlation weight, and the aging compensation coefficient.

8. The independently controlled automobile power blocking method according to claim 5, characterized in that: Before generating a comprehensive risk factor based on the failure probability and combining the temperature field abnormal distribution area ratio and the gas concentration mutation index, the following steps are also included: Real-time monitoring of the cell voltage difference between every two adjacent cells; The method of generating a comprehensive risk factor based on the failure probability and combining the temperature field abnormal distribution area ratio and the gas concentration mutation index includes the following steps: If the voltage differences of all the battery cells are less than a fourth preset threshold, a comprehensive risk factor is generated based on the failure probability, the proportion of abnormal temperature field distribution areas, and the gas concentration mutation index; After the real-time monitoring of the cell voltage difference between every two adjacent cells, the following steps are also included: If at least one of the battery cell voltage differences is greater than or equal to a fourth preset threshold, the position corresponding to the battery cell voltage difference is taken as the abnormal battery cell position; If the temperature gradient of the local hot spot area obtained through the temperature field distribution matrix is ​​greater than the fifth preset threshold, and the local hot spot area coincides with the position of the abnormal battery cell, a primary decision signal indicating that battery cell-level directional detonation is required is triggered.

9. The independently controlled automobile power blocking method according to claim 5, characterized in that: The driving power cut-off module performs the power cut-off action, including the following steps: Drive the mechanical burst fuse to perform mechanical blocking, and collect the residual voltage after mechanical blocking; If the residual voltage after blocking is in the first-level failure range, the electronic fuse backup unit is activated to forcibly disconnect the high-voltage circuit through the IGBT device and inject reverse current into the adjacent module to offset the residual potential.

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