Electrical system risk early warning method and system

Abstract

This application discloses a method and system for early warning of electrical system risks. The method includes: continuously collecting real-time data of monitored parameters in a vehicle's electrical system; performing a two-dimensional parallel judgment on the real-time data, which includes comparing the absolute value of the parameter with an absolute value threshold, and calculating the rate of change of the parameter and comparing it with a rate of change threshold; triggering an early warning signal when either comparison result is true. The system includes a data acquisition unit, a processing unit, and an early warning unit configured to execute the method. By introducing a rate of change judgment dimension, this application can capture early warning signs where the absolute value has not yet exceeded the limit, and confirm the abnormal rate of change through frequency conversion sampling and dynamic impedance analysis, thereby improving the speed of early warning while effectively suppressing false alarms.

Description

Technical Field

[0001] This application relates to the field of electrical safety monitoring technology, and in particular to a method and system for early warning of electrical system risks. Background Technology

[0002] For vehicles, especially modern vehicles with highly integrated and complex electrical systems, the safety of their electrical systems is paramount. Traditional electrical system safety protection devices, such as fuses or circuit breakers, primarily rely on monitoring the absolute value of the current. When the current exceeds a preset fusing threshold, the protection device cuts off the circuit, thereby preventing equipment damage or fire. In addition, some advanced monitoring systems also monitor the absolute values ​​of parameters such as voltage and temperature; for example, they may issue alarms when the battery voltage falls below the undervoltage protection value or the temperature exceeds the overheat threshold.

[0003] However, these early warning methods, which rely solely on a single "absolute value" threshold, have inherent limitations. The main problem lies in their delayed response, failing to provide effective early warnings of rapidly deteriorating potential risks. For example, in the initial stages of an electrical short circuit or battery thermal runaway, relevant parameters (such as voltage, current, or temperature) may change drastically within a very short time, but their absolute values ​​may not yet reach the set danger limits. If the system must wait until the absolute value of the parameter exceeds the threshold before reacting, the optimal intervention time has often been missed, and damage may have already occurred or even escalated. For instance, a battery pack with a nominal voltage of 12V may have an undervoltage protection threshold set at 11V. If the battery drops from 13V to 11.5V within one second due to an internal short circuit, the absolute value may not yet trigger an alarm, but the huge rate of change clearly indicates a serious fault. Traditional alarm systems are insufficient in identifying such risks; therefore, a technical solution capable of identifying potential risks in electrical systems earlier and more sensitively is urgently needed. Summary of the Invention

[0004] The technical problem that this invention aims to solve is that existing vehicle electrical system alarm methods rely excessively on a single absolute value judgment, resulting in delayed response and an inability to provide early warning of rapidly deteriorating risks.

[0005] To achieve the above objectives, this application provides an electrical system risk early warning method, comprising the following steps: continuously collecting real-time data of at least one monitoring parameter in the vehicle electrical system; performing a two-dimensional parallel judgment on the real-time data, wherein the two-dimensional parallel judgment includes: comparing the absolute value of the monitoring parameter with a preset absolute value threshold; calculating the rate of change of the monitoring parameter and comparing the rate of change with a preset rate of change threshold; triggering an early warning signal when the comparison result of the absolute value of the monitoring parameter exceeding the absolute value threshold is valid, or the comparison result of the rate of change exceeding the rate of change threshold is valid.

[0006] Furthermore, the step of calculating the rate of change of the monitoring parameter specifically includes: acquiring monitoring parameter sample values ​​at least two different times within a preset time window; and calculating the rate of change based on the difference between the monitoring parameter sample values ​​at the at least two different times and the time interval between the at least two different times.

[0007] Furthermore, the preset time window is a dynamic time window, and the method further includes: acquiring status information representing the current working state of the vehicle; and adaptively adjusting the duration of the dynamic time window based on the status information.

[0008] Furthermore, when the comparison result of the rate of change exceeding the rate of change threshold is true, the method further includes a confirmation step before triggering the warning signal. The confirmation step includes: in response to the rate of change exceeding the rate of change threshold, switching the sampling frequency of the real-time data from the reference sampling frequency to a preset high-frequency sampling frequency; synchronously acquiring voltage data and current data at the high-frequency sampling frequency, and calculating the instantaneous equivalent impedance based on the voltage data and the current data; determining whether the instantaneous equivalent impedance is lower than a preset short-circuit impedance threshold, and if the determination result is yes, then confirming the triggering of the warning signal.

[0009] Furthermore, the parameters in the confirmation step are further limited as follows: the high-frequency sampling frequency is configured to be no less than 1 kHz; the short-circuit impedance threshold is configured to be no more than 0.1 ohms; and the calculation of the instantaneous equivalent impedance is based on the synchronous voltage and current data collected within a capture period lasting no more than 10 milliseconds after switching to the high-frequency sampling frequency.

[0010] To achieve the above objectives, this application also provides an electrical system risk early warning system, comprising: a data acquisition unit for continuously acquiring real-time data of at least one monitoring parameter in the vehicle electrical system; a processing unit electrically connected to the data acquisition unit; and an early warning unit electrically connected to the processing unit; wherein the processing unit is configured to: receive the real-time data acquired by the data acquisition unit; perform a two-dimensional parallel judgment on the real-time data, the two-dimensional parallel judgment including: comparing the absolute value of the monitoring parameter with a preset absolute value threshold, and calculating the rate of change of the monitoring parameter and comparing the rate of change with a preset rate of change threshold; and when it is determined that the absolute value of the monitoring parameter exceeds the absolute value threshold, or the rate of change exceeds the rate of change threshold, drive the early warning unit to generate an early warning signal.

[0011] Furthermore, when the processing unit is configured to calculate the rate of change, it specifically performs the following: within a dynamic time window that adaptively adjusts the duration according to the current operating state of the vehicle, it acquires the sampled values ​​of the monitoring parameters collected by the acquisition unit at at least two different times; and calculates the rate of change based on the difference between the sampled values ​​of the monitoring parameters at the at least two different times and the time interval between the at least two different times.

[0012] Furthermore, the processing unit is further configured to: after determining that the rate of change exceeds the rate of change threshold, execute confirmation logic; the confirmation logic includes: controlling the acquisition unit to switch its sampling frequency from the reference sampling frequency to a preset high-frequency sampling frequency; calculating the instantaneous equivalent impedance based on the synchronous voltage data and current data acquired at the high-frequency sampling frequency; and determining whether the instantaneous equivalent impedance is lower than a preset short-circuit impedance threshold. If the determination result is yes, then confirm driving the warning unit.

[0013] Furthermore, the parameters used by the processing unit when executing the confirmation logic are configured as follows: the high-frequency sampling frequency is not lower than 1 kHz; and the short-circuit impedance threshold is not higher than 0.1 ohms.

[0014] Furthermore, the monitoring parameters include at least one of the following: the output voltage of the vehicle battery pack, the real-time current of the main line of the vehicle electrical system, or the surface temperature of the power devices associated with the electrical system.

[0015] The beneficial effects of this application are as follows:

[0016] By innovatively introducing "rate of change" as a monitoring dimension parallel to "absolute value", this application is able to capture risk precursors of drastic parameter changes before the absolute value exceeds the limit, thus issuing early warnings earlier than traditional methods and buying time for protective measures.

[0017] The rate-of-change-based judgment mechanism enables the system to react to transient and drastic changes in electrical parameters within milliseconds, achieving rapid protection and improving the system's safety response speed.

[0018] By introducing confirmation mechanisms such as "frequency conversion sampling" and "dynamic impedance analysis" after abnormal rate of change, it is possible to accurately distinguish between actual short-circuit faults and parameter fluctuations caused by normal startup of high-power loads, effectively suppressing false alarms and improving the stability and reliability of the system.

[0019] The "absolute value-rate of change" dual-dimensional monitoring logic proposed in this application is universal and can be applied to the monitoring of various key parameters such as voltage, current, and temperature in vehicle electrical systems. Attached Figure Description

[0020] To more clearly illustrate the technical solutions 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.

[0021] Figure 1 This is a structural block diagram of an electrical system risk early warning system provided in an embodiment of the present invention.

[0022] Figure 2 This is a flowchart illustrating an electrical system risk warning method provided in an embodiment of the present invention. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1

[0025] This embodiment provides an electrical system risk early warning system. (Refer to...) Figure 1 This system is a preferred hardware implementation scheme of this application, and is particularly suitable for application scenarios with high electrical safety requirements, such as vehicles. The system's physical architecture is centered around an intelligent power distribution control unit 101.

[0026] The intelligent power distribution control unit 101 integrates a processing unit 103, which can be a high-performance microcontroller. This processing unit 103 can run a real-time operating system to ensure that the risk warning algorithm is processed promptly as a top priority task. The system also includes a data acquisition unit 102 and a warning unit 104 electrically connected to the processing unit 103.

[0027] The acquisition unit 102 is responsible for continuously acquiring real-time data of at least one monitored parameter in the vehicle's electrical system. In this embodiment, the monitored parameter may include at least one of the following: the output voltage of the vehicle battery pack, the real-time current of the main circuit of the vehicle electrical system, or the surface temperature of the power devices associated with the electrical system. To achieve high-precision data acquisition, the acquisition unit 102 may include a multi-channel high-precision analog-to-digital converter. Specifically, for current acquisition, a low-resistance shunt, such as a 100-microohm shunt, can be connected in series at the positive input terminal of the battery pack, and the main circuit current can be calculated by measuring the voltage difference across its terminals. For voltage and temperature acquisition, appropriate voltage sampling circuits and temperature sensors can be used. The acquisition unit 102 converts the acquired analog signals into digital real-time data and transmits them to the processing unit 103.

[0028] The processing unit 103 is the control core of the system and is configured to execute the risk warning logic described in this application. The processing unit 103 receives real-time data collected by the acquisition unit 102 and performs a two-dimensional parallel judgment on it. The logic of this two-dimensional parallel judgment is as follows: on the one hand, the processing unit 103 compares the absolute value of the monitored parameter with a preset absolute value threshold. On the other hand, the processing unit 103 calculates the rate of change of the monitored parameter in parallel and compares this rate of change with a preset rate of change threshold.

[0029] When the processing unit 103 determines that the absolute value of the monitored parameter exceeds the absolute value threshold, or determines that its rate of change exceeds the rate of change threshold, that is, when the "or" logic judgment condition is met, it will drive the early warning unit 104 to generate an early warning signal.

[0030] After receiving the drive command from the processing unit 103, the early warning unit 104 executes the corresponding early warning action. The early warning signal can be a combination of one or more forms; for example, it can be connected to the vehicle's CAN bus to display alarm information of a severe level on the central control human-machine interface, or it can drive a buzzer, warning lights, etc., to emit an audible and visual alarm. In some embodiments, the early warning unit 104 can also integrate a cut-off execution module, which is integrated into the intelligent power distribution control unit 101. This module can directly and physically cut off the circuit to a specific load, thereby achieving proactive risk avoidance.

[0031] In a preferred embodiment, the processing unit 103 employs a dynamic time window-based algorithm when calculating the rate of change of the monitored parameters to balance monitoring sensitivity and stability. Specifically, within a time window, the processing unit 103 acquires sampled values ​​of the monitored parameters collected by the acquisition unit 102 at at least two different times, and calculates the rate of change based on the difference between these sampled values ​​and the time interval. The duration of this time window is adaptively adjusted according to the current operating state of the vehicle. For example, the system can acquire vehicle status information via the CAN bus. When the status information indicates that the vehicle is in a driving state, electrical system fluctuations may be more frequent, and the processing unit 103 will shorten the duration of the dynamic time window to improve monitoring sensitivity; when the status information indicates that the vehicle is in a static parking state, the duration of the dynamic time window will be lengthened to filter out normal fluctuations caused by slow environmental changes, thereby reducing the false judgment rate.

[0032] Furthermore, to address the issue of false alarms caused by rapid changes in normal parameters during the startup of high-power equipment, this embodiment introduces a confirmation mechanism based on dynamic impedance analysis. The processing unit 103 is further configured to, after initially determining that the rate of change of the monitored parameters exceeds the rate of change threshold, not immediately activate the early warning unit 104, but instead execute a confirmation logic first.

[0033] The confirmation logic includes: the processing unit 103 controls the acquisition unit 102 to switch its sampling frequency from a lower reference sampling frequency to a preset high-frequency sampling frequency. In high-speed sampling mode, the processing unit 103 calculates the instantaneous equivalent impedance based on the synchronously acquired voltage and current data. This calculation logic can be implemented using the following formula:

[0034]

[0035] in, express The instantaneous equivalent impedance at time t. and These represent the voltage and current values ​​acquired synchronously, respectively.

[0036] Processing unit 103 determines whether the calculated instantaneous equivalent impedance is lower than a preset short-circuit impedance threshold. This short-circuit impedance threshold, also known as the inherent impedance threshold of the line, is calibrated based on physical parameters such as the conductor diameter and length of the vehicle's wiring. In a preferred configuration, this threshold is no higher than 0.1 ohms. If the determination result is yes, that is, the instantaneous equivalent impedance rapidly drops to a range close to zero and cannot recover, then processing unit 103 determines that a real short-circuit fault has occurred, and only then confirms the drive warning unit 104. Conversely, if the instantaneous equivalent impedance drops but stabilizes at a clearly non-zero value, it is determined that a large load has started normally, and the alarm is suppressed, with only the event log recorded. Through this confirmation mechanism, the system can reduce the false alarm rate to below 0.1% while maintaining a millisecond-level response speed. In a specific embodiment, when the processing unit executes the confirmation logic, the high-frequency sampling frequency is configured to be no lower than 1 kHz, and the short-circuit impedance threshold is configured to be no higher than 0.1 ohms.

[0037] In summary, the system in this embodiment achieves early risk detection through parallel judgment of "absolute value-rate of change" and high accuracy through the collaborative confirmation mechanism of "frequency conversion sampling-dynamic impedance analysis", thus solving the inherent contradiction between sensitivity and stability in traditional early warning systems.

[0038] Example 2

[0039] This embodiment provides a method for early warning of electrical system risks, which can be executed by the system described in Embodiment 1. (Refer to...) Figure 2 The method includes the following steps:

[0040] Continuously collect real-time data of monitoring parameters.

[0041] The acquisition unit 102 in the system continuously acquires real-time data of at least one key monitoring parameter in the vehicle's electrical system at a certain sampling frequency and transmits the data to the processing unit 103. In normal inspection mode, a reference sampling frequency can be used to reduce system power consumption.

[0042] Perform parallel judgment on real-time data in two dimensions.

[0043] After receiving the real-time data, the processing unit 103 initiates a parallel processing path. This judgment process is divided into two parallel branches: absolute value comparison and rate of change calculation and comparison.

[0044] The absolute value of the monitored parameter is compared with the absolute value threshold.

[0045] The processing unit 103 directly compares the absolute value of the currently acquired monitoring parameter with the preset absolute value threshold in the memory. If the comparison result is true, the judgment condition is met.

[0046] Calculate the rate of change of the monitored parameters and compare it with the rate of change threshold.

[0047] In parallel, the processing unit 103 uses a data buffer to calculate the rate of change of the monitored parameters. Specifically, within a preset time window, it acquires sampled values ​​of the monitored parameters at at least two different times; then, based on the difference between these two sampled values ​​and the time interval between them, it calculates the rate of change.

[0048] For example, if the monitored parameter is voltage The calculation logic for its rate of change can be approximated by first-order difference. In a preferred embodiment, the above calculation logic is implemented by the following formula:

[0049]

[0050] in, Indicates the rate of change of voltage. and They are time points and The voltage sample value.

[0051] Subsequently, the processing unit 103 compares the calculated rate of change with a preset rate of change threshold. If the comparison result is true, the judgment condition is met.

[0052] Perform a logical "OR" judgment.

[0053] Processing unit 103 performs a logical "OR" operation on the comparison results of the aforementioned steps. This means that as long as either of the two conditions is true, namely "absolute value exceeds the limit" or "rate of change exceeds the limit", the judgment process will continue.

[0054] An early warning signal has been triggered.

[0055] When the logical judgment result is true, the processing unit 103 drives the early warning unit 104 to trigger the early warning signal.

[0056] In a more refined implementation, to further improve the accuracy of the warning, the method enters an optional confirmation step after the rate of change exceeds the limit. This confirmation step is specifically designed to distinguish between a genuine fault and a normal high-load startup.

[0057] The confirmation step specifically includes:

[0058] In response to the rate of change exceeding the rate of change threshold, the sampling frequency of data acquisition is immediately switched from the reference sampling frequency to the preset high-frequency sampling frequency.

[0059] In high-frequency sampling mode, voltage and current data are acquired synchronously. Based on the data captured in this high-frequency sampling mode, the instantaneous equivalent impedance is calculated within a capture period of no more than 10 milliseconds. This calculation is based on the synchronous voltage and current data, using the formula... accomplish.

[0060] Determine whether the instantaneous equivalent impedance is lower than the preset short-circuit impedance threshold. If the determination result is yes, it is confirmed as a real short-circuit risk, and only then is a warning signal triggered; if the determination result is no, it is determined to be a normal operating condition such as heavy load startup, the alarm is suppressed, the process ends or returns to the normal monitoring state.

[0061] To verify the effectiveness of the proposed solution, a test platform was built, comprising a lithium battery pack, an inverter, and a simulated short-circuit breaker. The tests compared three solutions: the "traditional absolute value mode," the "traditional rate of change mode," and the "proposed solution mode (dual-dimensional + impedance verification)." The performance comparison test data are shown in the table below:

[0062] Test conditions Traditional absolute value model (threshold 11V) Traditional rate of change model (threshold -0.5V / 100ms) This application mode (two-dimensional + impedance) True short circuit simulation (0.01Ω contact) Response time 2500ms (severe lag) Response time 5ms Response time: 8ms (including computation time and security considerations) Air conditioner starts (inrush current 80A) No police report False alarm (system power failure) No alarm (identified as load connection) Microwave oven starts (inrush current 150A) No police report False alarm (system power failure) No alarm (identified as load connection) Battery pack thermal runaway (gradual voltage drop + rapid voltage drop) Call the police (but it might be too late). Call the police Alarm (early warning)

[0063] As shown in the table above, while the traditional rate-of-change mode offers a fast response, it generates false alarms during high-power load startup. The proposed mode, while maintaining a near-simple rate-of-change mode's rapid response, completely eliminates false alarms during load startup, achieving a balance between speed and accuracy in early warning and meeting the substantive requirements of automotive-grade safety systems.

[0064] It should be noted that the above embodiments are only preferred solutions of this application. Those skilled in the art can make various modifications and changes based on the above ideas. For example, the specific selection of each hardware unit, the specific numerical setting of the parameter threshold, and the specific calculation method of the rate of change can all be adjusted according to the actual application scenario. These modifications and changes should all be included within the protection scope of this invention.

[0065] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for early warning of electrical system risks, characterized in that, Includes the following steps: Continuously collect real-time data of at least one monitoring parameter in the vehicle's electrical system; The real-time data is subjected to a two-dimensional parallel judgment, which includes: The absolute value of the monitored parameter is compared with a preset absolute value threshold; Calculate the rate of change of the monitored parameter and compare the rate of change with a preset rate of change threshold; An early warning signal is triggered when the comparison result of the absolute value of the monitored parameter exceeding the absolute value threshold is true, or when the comparison result of the rate of change exceeding the rate of change threshold is true.

2. The method according to claim 1, characterized in that, The steps for calculating the rate of change of the monitored parameters specifically include: Within a preset time window, acquire monitoring parameter sampling values ​​at at least two different times; The rate of change is calculated based on the difference between the sampled values ​​of the monitoring parameters at at least two different times and the time interval between the at least two different times. Wherein, if the monitoring parameter is voltage Then its rate of change pass The logic is determined, where and They are time points and The voltage sample value.

3. The method according to claim 2, characterized in that, The preset time window is a dynamic time window, and the method further includes: Obtain status information representing the current operating state of the vehicle; The duration of the dynamic time window is adaptively adjusted based on the status information. Specifically, when the status information indicates that the vehicle is in a driving state, the duration of the dynamic time window is shortened to improve monitoring sensitivity; when the status information indicates that the vehicle is in a static parking state, the duration of the dynamic time window is lengthened to reduce misjudgments caused by slow changes in the environment.

4. The method according to claim 1, characterized in that, When the comparison result of the rate of change exceeding the rate of change threshold is true, the method further includes a confirmation step before triggering the warning signal. The confirmation step includes: In response to the rate of change exceeding the rate of change threshold, the sampling frequency of the real-time data is switched from the reference sampling frequency to a preset high-frequency sampling frequency; At the high-frequency sampling frequency, voltage and current data are collected synchronously, and the instantaneous equivalent impedance is calculated based on the voltage and current data. Determine whether the instantaneous equivalent impedance is lower than a preset short-circuit impedance threshold. If the determination result is yes, then confirm the triggering of the warning signal.

5. The method according to claim 4, characterized in that, The parameters in the confirmation step are further defined as follows: The high-frequency sampling frequency is configured to be no less than 1 kHz; The short-circuit impedance threshold is configured to be no higher than 0.1 ohms; Furthermore, the calculation of the instantaneous equivalent impedance is based on the synchronous voltage and current data collected within a capture period of no more than 10 milliseconds after switching to the high-frequency sampling frequency.

6. An electrical system risk early warning system, characterized in that, include: The acquisition unit is used to continuously acquire real-time data of at least one monitoring parameter in the vehicle's electrical system; The processing unit is electrically connected to the acquisition unit; The early warning unit is electrically connected to the processing unit; The processing unit is configured as follows: Receive the real-time data collected by the acquisition unit; Perform a two-dimensional parallel judgment on the real-time data. The two-dimensional parallel judgment includes: comparing the absolute value of the monitoring parameter with a preset absolute value threshold, and calculating the rate of change of the monitoring parameter and comparing the rate of change with a preset rate of change threshold. When it is determined that the absolute value of the monitoring parameter exceeds the absolute value threshold, or when it is determined that the rate of change exceeds the rate of change threshold, the early warning unit is driven to generate an early warning signal.

7. The system according to claim 6, characterized in that, When the processing unit is configured to calculate the rate of change, it specifically performs the following: Within a dynamic time window that adaptively adjusts the duration based on the vehicle's current operating status, the sampled values ​​of the monitoring parameters collected by the acquisition unit at at least two different times are acquired. The rate of change is calculated based on the difference between the sampled values ​​of the monitoring parameters at at least two different times and the time interval between the at least two different times.

8. The system according to claim 6, characterized in that, The processing unit is further configured to: After determining that the rate of change exceeds the rate of change threshold, the confirmation logic is executed; The confirmation logic includes: controlling the acquisition unit to switch its sampling frequency from the reference sampling frequency to a preset high-frequency sampling frequency; calculating the instantaneous equivalent impedance based on the synchronous voltage and current data acquired at the high-frequency sampling frequency; and determining whether the instantaneous equivalent impedance is lower than a preset short-circuit impedance threshold. If the determination result is yes, then confirming the activation of the warning unit.

9. The system according to claim 8, characterized in that, The parameters used by the processing unit when executing the confirmation logic are configured as follows: The high-frequency sampling frequency is not less than 1 kHz; The short-circuit impedance threshold is no higher than 0.1 ohms.

10. The system according to claim 6, characterized in that, The monitoring parameters include at least one of the following: the output voltage of the vehicle battery pack, the real-time current of the main line of the vehicle electrical system, or the surface temperature of the power devices associated with the electrical system.

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