Fast breaking device and system against arc fault

Abstract

The application discloses a rapid breaking device and system for arc fault, and the device comprises an arc fault detection module, a control module and a rapid breaking module, wherein the arc fault detection module is used for collecting target working data of a low-voltage direct-current system; determining a target fault detection result according to the target working data; the target fault detection result comprises one of the following: an arc fault exists or an arc fault does not exist; the control module is used for generating a target breaking instruction when the target fault detection result comprises the arc fault; and the rapid breaking module is used for performing a breaking operation according to the target breaking instruction to reduce the safety risk. The embodiment of the application improves the accuracy of arc fault detection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of arc fault, and in particular to a quick breaking device and system for arc fault. BACKGROUND

[0002] In the operation process of a low-voltage direct-current system, once an arc fault occurs, it will release intense heat instantaneously, which is extremely easy to cause an electrical fire accident and poses a major threat to the stable operation of the electrical system.

[0003] At present, a detection method based on radiation characteristics is generally used to detect arc faults. This method can accurately locate the arc under laboratory conditions, but in actual application, high-frequency noise generated by inverters, communication equipment and the like will interfere with the detection, resulting in an increased false positive rate and low accuracy. For example, in a photovoltaic microgrid, the PWM modulation signal of the inverter overlaps with the arc radiation frequency band, and it is difficult to effectively distinguish them. Therefore, the problem of how to improve the accuracy of arc fault detection needs to be solved urgently. SUMMARY

[0004] The embodiments of the present application provide a quick breaking device and system for arc fault, which improves the accuracy of arc fault detection.

[0005] In a first aspect, the embodiments of the present application provide a quick breaking device for arc fault, which is applied to a low-voltage direct-current system and includes an arc fault detection module, a control module and a quick breaking module, wherein:

[0006] The arc fault detection module is configured to collect target working data of the low-voltage direct-current system, determine a target fault detection result according to the target working data, and the target fault detection result includes one of the following: an arc fault exists or an arc fault does not exist.

[0007] The control module is configured to generate a target breaking instruction when the target fault detection result includes the arc fault exists.

[0008] The quick breaking module is configured to perform a breaking operation according to the target breaking instruction to reduce the safety risk.

[0009] In a second aspect, the embodiments of the present application provide a quick breaking system for arc fault, which includes the quick breaking device for arc fault as described in the first aspect.

[0010] In a third aspect, the embodiments of the present application provide a quick breaking method for arc fault, which is applied to the quick breaking device for arc fault as described in the first aspect and includes the following steps:

[0011] The arc fault detection module collects target working data of the low-voltage direct-current system; a target fault detection result is determined according to the target working data; the target fault detection result includes one of the following: an arc fault exists, or an arc fault does not exist;

[0012] The control module generates a target breaking instruction when the target fault detection result includes the arc fault existing;

[0013] The rapid breaking module performs a breaking operation according to the target breaking instruction to reduce a safety risk.

[0014] In a fourth aspect, an electronic device is provided, including a processor, a memory, a communication interface, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the processor, and the programs include instructions for performing the steps in the third aspect of the embodiments.

[0015] In a fifth aspect, a computer-readable storage medium is provided, which stores a computer program for electronic data exchange, wherein the computer program causes a computer to perform some or all of the steps described in the third aspect of the embodiments.

[0016] In a sixth aspect, a computer program product is provided, which includes a non-transitory computer-readable storage medium storing a computer program, and the computer program is operable to cause a computer to perform some or all of the steps described in the third aspect of the embodiments. The computer program product can be a software installation package.

[0017] The present application has the following advantages:

[0018] As can be seen, the rapid breaking device for arc faults described in the present application collects target working data (such as voltage, current, and other signals) of a low-voltage direct-current system through an arc fault detection module; the target working data is analyzed, and when an arc fault occurs, the voltage and current of the system will exhibit unique transient characteristics (such as waveform distortion, high-frequency pulsation, abnormal mutation slope, etc.), thereby obtaining a target fault detection result. Compared with a detection method based on radiation characteristics, the device analyzes the characteristics of the working electrical signals of the low-voltage direct-current system, can avoid the interference dilemma of "radiation frequency band overlap", does not need to rely on radiation signals that are easily contaminated by noise, but distinguishes based on the characteristic differences between arc and noise in electrical signals, thereby reducing misjudgment and improving the accuracy of arc fault detection. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background, the drawings needed to be used in the embodiments of the present application or the background will be described below.

[0020] Figure 1 is an application scenario of a fast breaking device for arc fault provided by an embodiment of the present application;

[0021] Figure 2 is a structural schematic diagram of a fast breaking device for arc fault provided by an embodiment of the present application;

[0022] Figure 3 is a flowchart of a method for determining a target fault detection result provided by an embodiment of the present application;

[0023] Figure 4 is a flowchart of another method for determining a target fault detection result provided by an embodiment of the present application;

[0024] Figure 5 is a structural schematic diagram of a fast breaking module provided by an embodiment of the present application;

[0025] Figure 6 is a structural schematic diagram of another fast breaking device for arc fault provided by an embodiment of the present application;

[0026] Figure 7 is a flowchart of a fast breaking method for arc fault provided by an embodiment of the present application;

[0027] Figure 8 is a structural schematic diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0028] In order to make the person skilled in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative labor fall within the scope of protection of the present application.

[0029] The terms "first", "second", and the like in the description and in the claims of the present application and above-described drawings are used to distinguish different objects, and are not used to describe a particular order. In addition, the terms "comprise" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to these processes, methods, products, or devices.

[0030] It should be understood that the term "and / or" herein is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. In addition, the character " / " in this paper represents that the front and rear associated objects are a "or" relationship. "Multiple" in the embodiments of the present application means two or more.

[0031] The "at least one" or similar expressions in the embodiments of the present application mean any combination of these items, including any combination of single item or multiple items, means one or more, and multiple means two or more. For example, at least one of a, b or c can mean the following seven cases: a, b, c, a and b, a and c, b and c, a, b and c. Wherein, each of a, b and c can be an element or a set containing one or more elements.

[0032] The "connection" appearing in the embodiments of the present application means direct connection or indirect connection and various connection modes to realize communication between devices, which is not limited in the embodiments of the present application.

[0033] In this paper, "embodiment" means that the specific features, structures or characteristics described in conjunction with the embodiment can be included in at least one embodiment of the present application. The phrase appears at various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment to other embodiments. The skilled person in the art explicitly and implicitly understands that the embodiments described herein can be combined with other embodiments.

[0034] The electronic device described in the embodiments of the present application can include a smart phone (such as an Android phone, an iOS phone, a Windows Phone phone, etc.), a tablet computer, a palm computer, a notebook computer, a video matrix, a monitoring platform, a mobile internet device (MID) or a wearable device, etc. The above are only examples, not exhaustive, including but not limited to the above devices.

[0035] Of course, the above-mentioned electronic device can also be a rapid breaking device for arc fault.

[0036] The related content, concepts, meanings, technical problems, technical solutions, and beneficial effects involved in the embodiments of the present application are described below.

[0037] First, some professional terms involved in the present application are explained:

[0038] Low-voltage direct-current system: refers to a direct-current power supply system with a rated voltage usually below 1500V, widely used in distributed photovoltaic, energy storage systems, data centers, electric vehicle charging facilities and other scenarios. Its characteristics are high energy transmission efficiency, no phase problem of alternating current system, but the arc is not easy to extinguish (no natural zero point) when a fault occurs, and the rapidity and reliability of the protection device are required to be higher.

[0039] Arc fault: refers to a fault in a low-voltage direct-current system caused by poor conductor contact, insulation damage, line aging, etc., resulting in gas discharge phenomenon (arc) through air or insulation gap, leading to arc fault. Arc fault has the characteristics of high temperature (up to more than 3000 degrees Celsius) and high energy release, which can easily cause equipment burning or fire, and the direct current arc has no zero point, the duration is longer, and the harm is more significant.

[0040] Fault characteristic frequency of arc fault: refers to a specific high-frequency disturbance frequency component present in the voltage or current signal when an arc fault occurs, which is a key feature to distinguish arc fault from normal operating state. Its source is the periodic physical process of arc "extinguishing-rekindling", and the frequency range is usually hundreds of hertz to thousands of hertz, for example, series arc may cause 500Hz~700Hz current pulsation due to contact point oxidation layer, and parallel arc may cause 300Hz~800Hz voltage fluctuation due to air breakdown randomness.

[0041] Solid-state switch: a non-contact switch composed of power electronic devices (such as IGBT, MOSFET, etc.), which realizes conduction and turn-off through control electrode signal (voltage or current). Its core feature is fast action speed (microsecond level response), no mechanical wear, no arc generation (turn-off by device's own blocking characteristic to cut off current), but the on-state resistance is relatively large compared to mechanical switch, and there is certain power consumption in long-term conduction.

[0042] Mechanical switch: a switching device composed of mechanical contacts (such as metal contacts), which realizes conduction / isolation of circuit through closing / opening of contacts, typical representatives are circuit breakers, relays, etc. Its core feature is extremely low on-state resistance, negligible conduction loss, suitable for long-term carrying rated current, but the action speed is relatively slow (milliseconds), and if there is current when the contacts are opened, arc may be generated (leading to contact ablation).

[0043] Modbus: It is an industrial fieldbus communication protocol for digital communication between devices, and is one of the general standards in the field of industrial automation.

[0044] CAN bus: It is a multi-master serial communication bus developed by Bosch for automotive electronics, and later widely used in industrial control field, with the core features of high reliability and real-time performance.

[0045] DDS digital synthesizer: It is a device that generates high-precision and high-stability electrical signals through digital signal processing technology.

[0046] Please refer to Figure 1 , Figure 1 is an application scenario diagram of a fast breaking device for arc fault provided by the embodiments of the present application. As can be seen, the low-voltage direct current system includes a direct current power supply and a load; the fast breaking device for arc fault (hereinafter referred to as device) is installed between the direct current power supply and the load, becoming a “must-pass link” of the main current path.

[0047] Since the above-mentioned device is connected in series in the main current path, all the current output by the direct current power supply needs to pass through the device, so that the arc fault detection module in the device can collect complete loop current and / or voltage signals (including current characteristics during normal operation and fault), providing a data basis for accurate identification of arc fault; when the arc fault detection module determines that there is an arc fault, the fast breaking module in the device can cut off the series path where the device is located, directly blocking the current transmission from the direct current power supply to the load, realizing the rapid isolation of the fault loop, and avoiding the spread of arc to cause fire hazards and the like.

[0048] Please refer to Figure 2 , Figure 2 is a structural schematic diagram of a fast breaking device for arc fault provided by the embodiments of the present application; the device is applied to a low-voltage direct current system, as shown in Figure 2 , the device includes an arc fault detection module, a control module, and a fast breaking module, wherein:

[0049] The arc fault detection module is configured to collect target working data of the low-voltage direct current system; determine a target fault detection result according to the target working data; the target fault detection result includes one of the following: there is an arc fault, and there is no arc fault.

[0050] In the embodiments of the present application, the arc fault detection module can include a current sensor and a voltage sensor; wherein the bandwidth of the current sensor and the voltage sensor can be greater than or equal to 10 kHz (covering the upper limit of the arc fault characteristic frequency, for example, 1 kHz), ensuring that the high-frequency pulsating signal is not filtered out; the accuracy of the current sensor can be less than or equal to 0.5%, and the accuracy of the voltage sensor can be less than or equal to 1%, ensuring the accuracy of signal acquisition.

[0051] In specific embodiments, the arc fault detection module can use a current sensor to collect current data of the low-voltage DC system, covering the rated current range (e.g., 0-500 A) of the low-voltage DC system, and focusing on capturing current pulsations (e.g., current sudden drop and high-frequency fluctuations of series arc) during arc fault. In addition, a voltage sensor can be used to collect voltage data of the low-voltage DC system, monitor the bus voltage of the low-voltage DC system, and capture voltage distortion (e.g., voltage drop and spike of parallel arc) during arc fault. Then, the collected current and voltage data can be pre-processed (e.g., filtering and denoising, smoothing, and outlier rejection), to weaken noise interference and retain key features (e.g., waveform distortion pattern and mutation amplitude) related to arc fault in the current and voltage data, thereby obtaining target working data. Then, the target working data can be analyzed for fault to obtain target fault detection results.

[0052] In some embodiments, advanced signal processing algorithms (e.g., wavelet transform or fast Fourier transform) can be used to analyze the time-frequency domain characteristics of the collected current and voltage signals, focusing on both the change of the signals over time (time domain) and the frequency components contained therein (frequency domain), thereby identifying arc faults.

[0053] In some embodiments, the target working data can include data from multiple sources (e.g., voltage and current signals of each phase), from which more rich feature parameters (e.g., inclination angle, ellipticity, and major axis length of equivalent magnetization curve) than single threshold judgment can be extracted. By classifying different fault scenarios through these high-dimensional information, internal faults, external faults, and excitation inrush can be more accurately distinguished, solving the problem that traditional single parameter judgment cannot distinguish complex faults. For example, when the equivalent magnetization curve has a large inclination angle, an ellipticity close to 1, a phase difference of 180 degrees, and no waveform attenuation, it can be determined as an internal fault, triggering immediate tripping (i.e., immediate disconnection). When the equivalent magnetization curve has a medium inclination angle, a symmetric ellipticity, and a phase difference between 120 degrees and 150 degrees, it can be determined as an external fault, triggering delayed protection (i.e., delayed disconnection). When the equivalent magnetization curve has a long major axis, a periodically fluctuating inclination angle, a rapidly decaying waveform, and a high second harmonic ratio, it can be determined as an excitation inrush, without disconnection action.

[0054] In some embodiments, the target fault detection results can also include real-time fault information, which can include at least one of the following: arc fault type (e.g., series arc fault, parallel arc fault), fault occurrence time, fault location, current or voltage waveform during fault, action details of the disconnection module (e.g., disconnection time), fault duration, and the like, without limitation.

[0055] Optionally, in the step of collecting the target working data of the low-voltage direct-current system, the arc fault detection module is specifically configured to perform the following steps:

[0056] A1, determining a target arc fault set corresponding to the low-voltage direct-current system;

[0057] A2, determining a target fault characteristic frequency according to the target arc fault set;

[0058] A3, determining a reference sampling frequency according to the target fault characteristic frequency;

[0059] A4, determining a device performance parameter corresponding to the arc fault detection module;

[0060] A5, determining a target sampling frequency range corresponding to the device performance parameter;

[0061] A6, if the reference sampling frequency is within the target sampling frequency range, sampling working data of the low-voltage direct-current system according to the reference sampling frequency to obtain the target working data;

[0062] A7, if the reference sampling frequency is not within the target sampling frequency range, determining an intermediate value corresponding to the target sampling frequency range, determining a target sampling frequency according to the intermediate value, and sampling working data of the low-voltage direct-current system according to the target sampling frequency to obtain the target working data.

[0063] In the embodiments of the present application, the device performance parameter can include at least one of the following: device resolution, data processing speed, anti-electromagnetic interference capability, etc., which are not limited herein.

[0064] In specific embodiments, the target arc fault set corresponding to the low-voltage direct-current system can be determined first. Specifically, the target system type of the low-voltage direct-current system can be obtained, and then the target arc fault set is determined according to the target system type. For example, a mapping relationship between a preset system type and an arc fault set can be pre-stored, and the target arc fault set corresponding to the target system type is determined based on the mapping relationship. The target arc fault set contains all possible arc faults of the low-voltage direct-current system.

[0065] The target system type can include one of the following: photovoltaic direct-current system, energy storage direct-current system, data center direct-current power supply system, etc., which are not limited herein.

[0066] Then, the target fault characteristic frequency can be determined according to the target arc fault set. Specifically, the target arc fault set can include multiple arc faults, and the characteristic frequency corresponding to each arc fault can be determined to obtain multiple characteristic frequencies. For example, the characteristic frequency of the series arc caused by the loose cable joint is generally concentrated between 500-700 Hz, and the characteristic frequency corresponding to the series arc can be 700 Hz. The characteristic frequency of the parallel arc caused by the positive and negative insulation breakdown is generally concentrated between 300-500 Hz, and the characteristic frequency corresponding to the parallel arc can be 500 Hz. Then, the maximum characteristic frequency in the multiple characteristic frequencies, i.e., the target fault characteristic frequency, can be determined.

[0067] Further, the reference sampling frequency can be determined according to the target fault characteristic frequency. Specifically, according to the Nyquist sampling theorem, the sampling frequency should be at least twice the highest frequency component in the signal to ensure that the sampled signal can restore the original signal without distortion. Therefore, the reference sampling frequency can be twice the target fault characteristic frequency. Then, the device performance parameter corresponding to the arc fault detection module can be determined. Specifically, the device performance parameter can be the data processing speed. The module manual of the arc fault detection module can be obtained, and the device performance parameter of the arc fault detection module can be obtained from the module manual.

[0068] Then, the target sampling frequency range corresponding to the device performance parameter is determined. For example, assuming that the device performance parameter is the data processing speed of the arc fault detection module, the data processing speed is 1 MIPS (100 million instructions per second), and the full-process processing of each sampling point data requires an average of 50 instructions. Therefore, the maximum number of points processed per second is 1000000 / 50=20000, that is, the arc fault detection module can process up to 20,000 sampling point data per second. Therefore, the target sampling frequency range can be 0 Hz-20 kHz.

[0069] If the reference sampling frequency is within the target sampling frequency range, the arc fault detection module samples the working data of the low-voltage DC system at the reference sampling frequency to obtain the target working data.

[0070] If the reference sampling frequency is not within the target sampling frequency range, the intermediate value corresponding to the target sampling frequency range can be determined. For example, assuming that the target sampling frequency range is 1 kHz-3 kHz, the intermediate value is 2 kHz, which can be used as the target sampling frequency. The arc fault detection module samples the working data of the low-voltage DC system at the target sampling frequency to obtain the target working data.

[0071] Thus, the target fault feature frequency is determined according to the target arc fault set, and the reference sampling frequency is determined based on the Nyquist theorem, so as to fundamentally ensure that the sampling frequency can cover the high-frequency features of all arc faults, avoid feature loss caused by blind setting of the sampling frequency (such as aliasing caused by too low sampling frequency), and ensure that the subsequent algorithm can extract key features (such as high-frequency pulsation and waveform distortion) from the data, thereby laying a data foundation for accurate fault judgment.

[0072] Optionally, the target working data includes target voltage data, please refer to Figure 3 , Figure 3 is a flowchart of a target fault detection result determination method provided by the embodiment of the present application, and the arc fault detection module is specifically configured to perform the steps shown in Figure 3 ,

[0073] B1, segmenting the target voltage data according to a first preset time interval to obtain m pieces of voltage data; each piece of voltage data corresponds to a sampling time period; m is an integer greater than 1;

[0074] B2, determining the average value corresponding to each piece of voltage data in the m pieces of voltage data to obtain m average values; determining the absolute value of the difference between two adjacent average values in the m average values to obtain m-1 absolute values;

[0075] B3, determining the maximum value corresponding to the m-1 absolute values;

[0076] B4, when the maximum value is greater than a first preset value, determining that the target fault detection result includes the existing arc fault;

[0077] B5, when the maximum value is not greater than the first preset value, determining the absolute values greater than a second preset value in the m-1 absolute values to obtain n absolute values; the second preset value is less than the first preset value; n is a positive integer less than or equal to m-1; determining the i pieces of voltage data corresponding to the n absolute values in the m pieces of voltage data; i is an integer greater than n and less than or equal to m; determining the target fault detection result according to the i pieces of voltage data.

[0078] In the embodiment of the present application, the first preset time interval, the first preset value and the second preset value can be preset or defaulted in advance.

[0079] In specific embodiments, the target voltage data can be segmented according to a first preset time interval to obtain m pieces of voltage data. Specifically, starting from the starting time of the target voltage data, a piece of data is intercepted every time the first preset time interval elapses until the target voltage data is traversed to obtain m pieces of voltage data. Then, the average value corresponding to each piece of voltage data in the m pieces of voltage data can be determined to obtain m average values. Specifically, the average value of each piece of voltage data can be calculated according to an average value calculation formula to obtain m average values.

[0080] Then, the absolute value of the difference between adjacent two average values in the m average values can be determined to obtain m-1 absolute values. Specifically, the m average values can be arranged in time sequence first, and then the difference between adjacent two average values is calculated in sequence and the absolute value is taken, so as to obtain m-1 absolute values. Then, the maximum value in the m-1 absolute values can be found out. When the maximum value is greater than a first preset value, it can be determined that the target fault detection result includes the existence of arc fault.

[0081] When the maximum value is not greater than the first preset value, the absolute values greater than a second preset value in the m-1 absolute values can be found out to obtain n absolute values. Then, the i pieces of voltage data corresponding to the n absolute values in the m pieces of voltage data can be determined. Specifically, the i average values corresponding to the n absolute values in the m average values can be determined first, and then the i pieces of voltage data corresponding to the i average values in the m pieces of voltage data can be determined. For example, assuming that m=4, the 4 average values corresponding to the m pieces of voltage data are U1, U2, U3, and U4, wherein U1 represents the average value of the first piece of voltage data in the m pieces of voltage data, m-1=3, and the m-1 absolute values are k1=|U2-U1|, k2=|U3-U2|, and k3=|U4-U3|. Assuming that k1 and k2 are both greater than the second preset value, and k3 is less than the second preset value, n=2, the 3 average values U1, U2, and U3 corresponding to the n absolute values in the m average values, that is, i=3, and then the i pieces of voltage data corresponding to the i average values in the m pieces of voltage data can be determined, and the i pieces of voltage data include the first piece of voltage data, the second piece of voltage data, and the third piece of voltage data. Finally, the target fault detection result can be determined according to the i pieces of voltage data.

[0082] In this way, by segmenting the target voltage data according to the first preset time interval and calculating the average value, the essence is to perform time window smoothing on the original voltage signal. The average value can filter out transient interference (such as electromagnetic pulse and sharp peak generated by instantaneous load switching) in system operation and retain the trend change (such as continuous fluctuation caused by arc fault) of voltage, which is convenient for subsequent analysis.

[0083] In addition, by taking the maximum value of the m-1 absolute values and comparing the maximum value with the first preset value, a severe arc fault (such as voltage drop caused by parallel arc or voltage collapse caused by short-circuit arc) can be quickly locked. The voltage fluctuation amplitude of such a fault is large (the adjacent mean value difference is significant), and by comparing whether the maximum value exceeds the first preset value, the fault can be determined within 1-2 segment periods, meeting the rapid response requirement of the low-voltage direct-current system to severe faults.

[0084] Optionally, in the aspect of determining the target fault detection result according to the i pieces of voltage data, the arc fault detection module is specifically configured to perform the following steps:

[0085] C1, determining a maximum voltage change value corresponding to each piece of voltage data in the i pieces of voltage data, to obtain i maximum voltage change values;

[0086] C2, fitting each piece of voltage data in the i pieces of voltage data to obtain i voltage straight lines; the abscissa of each voltage straight line is time, and the ordinate is the voltage value;

[0087] C3, determining a slope corresponding to each voltage straight line in the i voltage straight lines, to obtain i slopes;

[0088] C4, determining a slope greater than 0 from the i slopes, and a slope not greater than 0 from the i slopes; a and b are natural numbers, and a+b=i;

[0089] C5, determining a target ratio according to the a slopes and the b slopes;

[0090] C6, determining the target fault detection result according to the i maximum voltage change values and the target ratio.

[0091] In the embodiments of the present application, the maximum voltage change value corresponding to each piece of voltage data in the i pieces of voltage data can be determined, to obtain i maximum voltage change values. Specifically, for each piece of voltage data, the minimum voltage value and the maximum voltage value can be obtained, and the maximum voltage change value can be obtained by subtracting the minimum voltage value from the maximum voltage value. In this way, i maximum voltage change values can be obtained.

[0092] Then, each piece of voltage data in the i pieces of voltage data can be fitted to obtain i voltage straight lines. For example, taking the first voltage data as an example, the first voltage data is any voltage data in the i pieces of voltage data, and the first voltage data includes a plurality of voltage values and a plurality of sampling times. The corresponding sampling times in the plurality of voltage values and the plurality of sampling times can be combined into a first coordinate point to obtain a plurality of first coordinate points. Then, a straight line fitting method (for example, the least square method) can be used to fit the plurality of first coordinate points to obtain a first straight line corresponding to the first voltage data. In this way, i voltage straight lines can be obtained.

[0093] Then, a slope corresponding to each of the i voltage straight lines can be determined, i.e., i slopes are obtained. Specifically, a straight line equation corresponding to each of the i voltage straight lines can be obtained, i.e., i straight line equations are obtained. The slopes are extracted from the i straight line equations, i.e., i slopes are obtained. For example, assuming that a straight line equation corresponding to a voltage straight line is y=kx+f, where k is the slope of the straight line, and f is the intercept of the straight line.

[0094] Then, a number a of slopes greater than 0 and a number b of slopes not greater than 0 among the i slopes can be determined. Specifically, the i slopes can be compared with 0 in sequence, i.e., a number a of slopes greater than 0 and a number b of slopes not greater than 0 are obtained. Further, a target ratio can be determined according to the a slopes and the b slopes. The specific calculation formula is as follows:

[0095] The target ratio=a / b.

[0096] According to the above formula, the target ratio can be obtained. Finally, a target fault detection result can be determined according to the i maximum voltage change values and the target ratio.

[0097] In this way, the maximum voltage change value reflects the fluctuation intensity in each segment of voltage data (for example, the voltage surge / drop amplitude when an arc fault occurs). The greater the maximum voltage change value, the more significant the deviation of the corresponding voltage data from the steady state, and the higher the possibility of an arc fault.

[0098] Optionally, in the aspect of determining the target fault detection result according to the i maximum voltage change values and the target ratio, the arc fault detection module is specifically configured to perform the following steps:

[0099] D1, obtaining a starting sampling time corresponding to each of the i maximum voltage change values, i.e., i starting sampling times are obtained;

[0100] D2, fitting according to the i maximum voltage change values and the i starting sampling times, i.e., a target voltage straight line is obtained. The horizontal coordinate of the target voltage straight line is time, and the vertical coordinate is voltage value;

[0101] D3, determining a target slope absolute value corresponding to the target voltage straight line;

[0102] D4, when the target slope absolute value is greater than a third preset value, determining that the target fault detection result includes the existence of an arc fault;

[0103] D5, when the target slope absolute value is not greater than the third preset value, determining a target variance corresponding to the i maximum voltage change values;

[0104] D6, determine a deviation between the target ratio and a fourth preset value, to obtain a target deviation;

[0105] D7, when the target deviation is greater than a preset deviation, and / or, the target variance is greater than a preset variance, determine that the target fault detection result includes the arc fault;

[0106] D8, when the target deviation is not greater than the preset deviation, and the target variance is not greater than the preset variance, determine that the target fault detection result includes the non-arc fault.

[0107] In the embodiments of the application, the third preset value, the fourth preset value and the preset deviation can be preset or defaulted in advance.

[0108] In specific embodiments, the starting sampling time corresponding to each of the i maximum voltage change values can be obtained, to obtain i starting sampling times. Specifically, the earliest sampling time corresponding to each of the i voltage data segments can be determined, to obtain i earliest sampling times, that is, i starting sampling times.

[0109] Then, the target voltage straight line can be obtained by fitting the i maximum voltage change values and the i starting sampling times. Specifically, the corresponding starting sampling time in the i maximum voltage change values and the i starting sampling times can be combined as a second coordinate point, to obtain i second coordinate points. Then, the straight line fitting method (for example, the least squares method) can be used to fit the i second coordinate points, to obtain the target voltage straight line.

[0110] Then, the target slope absolute value corresponding to the target voltage straight line can be determined. Specifically, the target straight line equation corresponding to the target voltage straight line can be obtained, the target slope can be determined according to the target straight line equation, and then the target slope absolute value can be obtained by taking the absolute value of the target slope. When the target slope absolute value is greater than the third preset value, it indicates that the voltage change rate has exceeded the normal range, and it is likely that the arc fault leads to violent fluctuations, so the target fault detection result can be determined as the arc fault.

[0111] When the target slope absolute value is not greater than the third preset value, the target variance corresponding to the i maximum voltage change values can be determined. Specifically, the target variance can be obtained by calculating the i maximum voltage change values according to the variance calculation formula. Then, the deviation between the target ratio and the fourth preset value can be determined. The specific calculation formula is as follows:

[0112] Target deviation = |target ratio-fourth preset value| / fourth preset value x 100%;

[0113] According to the above formula, the target deviation degree can be obtained; when the target deviation degree is greater than the preset deviation degree, and / or, the target variance is greater than the preset variance, the target fault detection result can be determined as existing arc fault; because the voltage signal of the arc fault has strong deviation, when the system is normally running, the voltage of the system fluctuates slightly around the steady state value, the deviation degree from the normal trend benchmark is small (such as when the load is stable, the voltage residual is less than 0.5V), which is less than the preset deviation degree, when the arc fault occurs, due to the unstable discharge process of "extinguishing-reigniting", the voltage will jump high frequency and disorderly, the deviation degree from the normal trend benchmark will increase significantly (the residual may reach more than 5V), which is far more than the preset deviation degree, therefore, when the target deviation degree exceeds the deviation degree, the essence is that the degree of "deviation from the normal trend" of the voltage signal has exceeded the reasonable range, so when the target deviation degree is greater than the preset deviation degree, it can be determined that the target fault detection result is an arc fault.

[0114] In addition, when the arc fault occurs, due to the "intermittency" of the arc discharge (millisecond-level extinguishing and reigniting), the voltage will frequently rise and fall sharply (for example, from 48V to 40V in an instant and then rise again), resulting in large data dispersion and significant variance exceeding the normal working condition (when the system is normally running, the voltage fluctuates smoothly and the variance is small), so when the target variance is greater than the preset variance, it can be determined that the target fault detection result is an arc fault.

[0115] When the target deviation degree is not greater than the preset deviation degree, and the target variance is not greater than the preset variance, the target fault detection result can be determined as not existing arc fault.

[0116] In this way, the target voltage straight line is fitted by "maximum voltage change value + initial sampling time", and the target slope absolute value is calculated, which essentially captures the overall trend rate of voltage fluctuation. Arc faults (such as short circuit and continuous poor contact) are often accompanied by "rapid unidirectional change" of voltage (such as rising or falling 20V per second), and the absolute value of the slope will far exceed the third preset value, which can directly determine the fault, achieve "millisecond-level" fast response, and avoid fault diffusion.

[0117] In addition, when the target slope absolute value is not greater than the third preset value, the target variance and the target deviation degree are introduced for analysis, the target variance reflects the dispersion degree of the i maximum voltage change values, and captures intermittent arc faults (such as intermittent discharge caused by vibration), which have no strong trend in voltage fluctuation, but the amplitude difference of single fluctuation is large, and the variance will exceed the standard, through the deviation of the target ratio (positive / negative slope ratio) and the fourth preset value (i.e. normal trend ratio), the trend consistency abnormal fault (such as continuous small amplitude voltage drop caused by joint oxidation) is captured, which has a small absolute value of the slope, but the proportion of negative slope deviates significantly from the normal, and the deviation degree will exceed the standard, and the joint judgment of the target variance and the target deviation degree can cover various arc faults and avoid missed detection.

[0118] Optionally, refer to Figure 4 , Figure 4 is another flowchart of a method for determining a target fault detection result provided in the embodiments of the present application, and in terms of determining a target fault detection result according to target working data, the arc fault detection module is specifically configured to perform the steps shown in Figure 4 .

[0119] E1, obtain a preset training data set and a test data set;

[0120] E2, train a preset AI model through the training data set to obtain a first AI model;

[0121] E3, test the first AI model through the test data set to obtain a first test result;

[0122] E4, determine a first accuracy rate corresponding to the first test result;

[0123] E5, when the first accuracy rate is greater than or equal to a preset accuracy rate threshold, determine a target AI model according to the first AI model;

[0124] E6, input the target working data into the target AI model to obtain the target fault detection result.

[0125] In the embodiments of the present application, the preset AI model and the preset accuracy rate threshold can be preset or defaulted in advance, wherein the preset AI model can include one of the following: convolutional neural network, recurrent neural network, random forest, etc., without limitation.

[0126] In specific embodiments, the preset training data set and the test data set can be obtained first, specifically, the historical working data of the low-voltage direct-current system can be obtained, each working data in the historical working data can be manually labeled with a label (the label can include: "normal label", "arc fault label"), and labeled data can be obtained, which can be randomly allocated according to a ratio of 7:3 to obtain the training data set and the test data set, for example, 70% as the training data set and 30% as the test data set.

[0127] Then, the preset AI model can be trained through the training data set to obtain a first AI model, for example, the first AI model can be a convolutional neural network, the training data set can be input into the preset AI model, the preset AI model can be trained by using a back propagation algorithm to obtain the first AI model, then the test data set can be input into the first AI model to obtain a first test result.

[0128] Then, a first accuracy rate corresponding to the first test result can be determined. Specifically, a first number of correct tests in the first test result can be determined first, obtaining a first number. Then, a total number of the first test result can be determined, and the first accuracy rate can be obtained by dividing the first number by the total number. When the first accuracy rate is greater than or equal to a preset accuracy rate threshold, the first AI model can be determined as a target AI model. Then, the target working data can be input into the target AI model to obtain a target fault detection result.

[0129] When the first accuracy rate is less than the preset accuracy rate threshold, new training data can be obtained, and the first AI model can be continuously trained by using the new training data until the accuracy rate of the first AI model is greater than the preset accuracy rate threshold. Then, the first AI model can be determined as the target AI model, and the target working data can be identified by using the target AI model to obtain the target fault detection result.

[0130] In this way, the model is trained by using the training data set and verified by using the test data set, so that the performance of the model on independent data meets the actual demand, and misjudgment or omission caused by direct application of a low-precision model without filtering is avoided.

[0131] In addition, compared with the traditional threshold method, the trained AI model can fuse multiple source features and still maintain a high accuracy rate in a complex scene with noise and interference, thereby improving the reliability of the target fault detection result and ensuring safe operation of the system.

[0132] The control module is configured to generate a target breaking instruction when the target fault detection result indicates that there is an arc fault.

[0133] In the embodiments of the present application, the control module can use a microprocessor or an application-specific integrated circuit as a core. The control module supports standard communication protocols such as Modbus and CAN bus, and can upload fault information and device operating status to an upper monitoring system (for example, a monitoring system of a low-voltage direct-current system) in real time. At the same time, the control module is equipped with a user interaction interface (such as an LED display screen or a touch screen) for intuitively displaying the current state of the rapid breaking device for arc faults and historical fault records, facilitating daily maintenance and management by maintenance personnel.

[0134] In specific embodiments, the control module can receive the target fault detection result sent by the arc fault detection module. After determining that the target fault detection result is an arc fault, the control module can first verify the validity of the fault signal (i.e., the target fault detection result) to avoid triggering a break due to a single false signal, for example, if the fault is determined in two consecutive detection periods, it is confirmed to be valid, otherwise it is invalid, thereby excluding temporary false positives. Then, a corresponding target break command (e.g., "emergency break", "delayed break") can be generated according to the fault severity (e.g., by judging the absolute value of the slope and the maximum voltage change), and parameters such as the break object (e.g., the specific loop number), the action time, etc. are determined. The target break command is sent to the fast break module to drive it to actuate and cut off the fault loop.

[0135] The fast break module is configured to execute a break operation according to the target break command to reduce the safety risk.

[0136] In the embodiments of the present application, after receiving the target break command, the fast break module executes a break operation according to the target break command to disconnect the fault loop of the low-voltage DC system.

[0137] Optionally, in some embodiments, please refer to Figure 5 , Figure 5 is a structural schematic diagram of a fast break module provided by an embodiment of the present application. As can be seen, the fast break module includes a solid-state switch and a mechanical switch. The solid-state switch and the mechanical switch are connected in parallel. Specifically, the solid-state switch can be directly connected in parallel with the main terminal of the mechanical switch, forming two current paths. The parallel switch group is connected in series to the main line (such as the positive or negative line) of the low-voltage DC system as a whole to realize on-off control of the entire loop. The fast break module is arranged between the power supply and the load in the low-voltage DC system.

[0138] When the low-voltage DC system is working normally, the solid-state switch and the mechanical switch are both in a closed state, and the working current of the low-voltage DC system is borne by the mechanical switch. This is because the conduction loop resistance of the mechanical switch (such as a traditional circuit breaker) is extremely small (usually in the order of milliohms), which generates less heat and has low loss when bearing the system working current for a long time, and is suitable for bearing continuous current-carrying tasks, thereby reducing energy loss in system operation. The solid-state switch is in a closed state. The solid-state switch (such as a semiconductor switch based on IGBT or MOSFET) has fast action capability (microsecond-level response), but has a certain voltage drop (usually a few volts) when conducting. The long-term current-carrying loss is high. When working normally, it is closed for "standby". Once the system detects a fault (such as an arc fault), it can be disconnected instantly to provide assistance for the break of the mechanical switch (such as cutting off the current first to avoid the generation of arc during the break of the mechanical switch).

[0139] In terms of executing a break operation according to the target break command, the fast break module is specifically configured to:

[0140] In response to the target breaking instruction, the solid-state switch is switched to the off state to cut off the current path. Since the solid-state switch has a response speed of microseconds, its conduction / off is controlled by an electrical signal (gate voltage) and does not require mechanical movement, and the state switching can be completed within a few microseconds. When the breaking instruction is received, the control circuit immediately cuts off the driving signal (such as the gate voltage of an IGBT) of the solid-state switch, so that the internal resistance of the solid-state switch instantaneously increases to the order of megohm, the current rapidly decreases to zero, and the current path is quickly cut off.

[0141] After cutting off the current path, the mechanical switch is automatically disconnected in a current-free environment. It needs to be explained that the breaking of the mechanical switch relies on the separation of the contacts, but in the presence of current, the separation of the contacts will generate an arc (especially in a direct current system, the arc is not easy to extinguish), resulting in contact ablation, shortened service life, and even secondary failure. However, since the solid-state switch has already cut off the current, the separation of the contacts of the mechanical switch is in a "current-free environment" and will not generate an arc, so the disconnection action can be safely and non-destructively completed. The automatic disconnection of the mechanical switch can be a delayed response to the target breaking instruction. After receiving the target breaking instruction, the fast breaking module first triggers the solid-state switch to quickly cut off the current (in microseconds), and then triggers the breaking mechanism (such as an electromagnet or spring release) of the mechanical switch through a pre-set time sequence (such as a delay of tens of milliseconds to ensure that the current has decreased to zero), to realize "automatic action in a current-free environment" and finally realize the physical isolation of the fault circuit (even if the solid-state switch accidentally conducts, the disconnection of the mechanical switch can also ensure the isolation of the circuit). In this way, the super-fast arc extinguishing is realized through the solid-state switch to meet the stringent requirements of safety standards for breaking speed, and the stable low-loss conduction and physical isolation are realized through the mechanical switch, while the problem of contact ablation is avoided, and the service life and reliability of the device are significantly improved.

[0142] Optionally, in some embodiments, the solid-state switch and the mechanical switch can be synchronously turned off.

[0143] Optionally, please refer to Figure 6 , Figure 6 is another structure diagram of a fast breaking device for arc fault provided by the embodiment of the present application, which comprises Figure 6 As can be seen, in addition to the arc fault detection module, the control module, and the fast breaking module, the device further comprises a self-diagnosis module, which is specifically configured to perform the following steps:

[0144] F1, detecting target state data of the device;

[0145] F2, determining a target state of the device according to the target state data; the target state includes: a normal state, an abnormal state;

[0146] F3, transmitting a first abnormality instruction to the control module when the target state comprises the abnormal state; the first abnormality instruction is used to indicate that the device has an abnormality.

[0147] In the embodiments of the present application, the self-diagnosis module can include temperature sensors, voltage sensors and the like, which are not limited herein; the target state data can include at least one of the following: contact wear degree of a mechanical switch, aging state of a solid-state switch, configuration parameters (for example, a first preset value) of the device, communication state, historical event record, power supply state, environmental data and the like, which are not limited herein.

[0148] In specific embodiments, the target state data of the device can be detected first, specifically, the target state data can include the contact wear degree of the mechanical switch and the aging state of the solid-state switch, the temperature sensor of the self-diagnosis module can be installed near the contact of the mechanical switch to monitor the temperature of the contact during operation, after the contact is worn, the contact resistance increases, the Joule heat increases, and the temperature will significantly rise (the temperature is stable within 10℃ of the ambient temperature under normal conditions, and after wear, the temperature can be 30℃ higher than the ambient temperature), the wear degree is determined by abnormal fluctuations in temperature, thereby obtaining the contact wear degree of the mechanical switch, then the voltage sensor can be used to monitor the tube voltage drop of the solid-state switch during conduction, and the tube voltage drop is compared with the initial calibration value, if the increase of the tube voltage drop exceeds a preset proportion (such as 20%), it is determined that there is aging, thereby obtaining the aging state of the solid-state switch.

[0149] Then, the target state of the device can be determined according to the target state data, specifically, a preset mapping relationship between the preset state data and the state can be stored in advance, and the target state corresponding to the target state data is determined based on the mapping relationship; when the target state includes an abnormal state, the self-diagnosis module can transmit a first abnormality instruction to the control module to indicate that the device may have a fault and needs to be manually repaired.

[0150] In some embodiments, the self-diagnosis module can use a specific intelligent algorithm (such as an arc current entropy detection algorithm based on a quantum probability model) to analyze the target state data, evaluate the overall health state of the device, and discover potential fault hazards in advance. When an abnormality (such as component aging, detection module response failure, etc.) is detected, an alarm can be sent to the control module (i.e., a first abnormality instruction is transmitted to the control module); if necessary, the operating parameters of the device can be automatically adjusted (such as reducing the load and optimizing the protection threshold), to avoid the expansion of the fault and ensure the continuous normal operation of the device.

[0151] When the target state includes a normal state, the first abnormality instruction does not need to be transmitted to the control module.

[0152] It needs to be explained that the self-diagnosis module has a periodic self-checking function (such as triggered once every 15 hours), when detecting an abnormality, the self-diagnosis module can send an alarm information to the control module, or automatically adjust the operating parameters to ensure the continuous and stable operation of the device.

[0153] In this way, by detecting the target state data in real time and distinguishing between normal and abnormal states, abnormalities can be identified before the device experiences serious malfunctions (such as slight wear of the contact, degradation of the element performance), avoiding the worsening of small problems leading to shutdown or safety accidents.

[0154] In addition, by transmitting the first abnormality instruction to the control module, the control module can quickly respond (such as sending an alarm to remind maintenance, adjusting the operating parameters to reduce the load), delaying the development of the abnormality by active intervention, avoiding the accumulation of abnormal states leading to chain failures (such as the aging of solid-state elements may cause delay in breaking), thereby prolonging the service life of the device.

[0155] Optionally, the self-diagnosis module is further configured to perform the following steps:

[0156] G1, generating an analog arc fault signal;

[0157] G2, transmitting the analog arc fault signal to the arc fault detection module;

[0158] G3, obtaining the detection result of the arc fault detection module for the analog arc fault signal to obtain a first detection result;

[0159] G4, if the first detection result is that the arc fault exists, it is determined that the arc fault detection module is in a normal working state;

[0160] G5, if the first detection result is that the arc fault does not exist, it is determined that the arc fault detection module is in an abnormal working state, and a second abnormality instruction is transmitted to the control module; the second abnormality instruction is used to indicate that the arc fault detection module has an abnormality.

[0161] In the embodiments of the present application, the self-diagnosis module can include a signal generator (such as a DDS digital synthesizer).

[0162] In specific embodiments, the self-diagnosis module can generate an analog arc fault signal, specifically, it can extract key features (for example, voltage mutation amplitude, high-frequency component, fluctuation period, etc.) based on a pre-set arc fault waveform database as a generation reference of the analog signal, then, through the above-mentioned signal generator, randomly generate an electric signal conforming to the above-mentioned key features, for example, a basic direct current signal can be constructed, and then a high-frequency pulsation with a pre-set amplitude and a random fluctuation component are superimposed to simulate the dynamic process of arc "extinguishing-reigniting".

[0163] Then, the simulated arc fault signal can be transmitted to the arc fault detection module, and a detection result of the arc fault detection module for the simulated arc fault signal is obtained to obtain a first detection result. Specifically, the self-diagnosis module can capture the output signal of the arc fault detection module in real time through a data acquisition line or a communication interface during the analysis of the arc fault detection module on the simulated arc fault signal, that is, the first detection result. If the first detection result is that there is an arc fault, it is determined that the arc fault detection module is in a normal working state.

[0164] If the first detection result is that there is no arc fault, it indicates that the fault detection function of the arc fault detection module is abnormal and cannot identify the fault type corresponding to the simulated arc fault signal. Then, it can be determined that the arc fault detection module is in an abnormal working state. The self-diagnosis module can transmit a second abnormal instruction to the control module to indicate that the fault detection method of the arc fault detection module has a vulnerability, prompting the staff to overhaul, parameter calibration or algorithm repair.

[0165] In this way, the known simulated arc fault signal test module can quickly verify whether it has normal detection capability, and potential problems (such as algorithm vulnerability and circuit fault) of the module can be found before a real fault occurs, so that the staff can repair it specifically, and the sudden accidents and maintenance costs caused by module faults can be reduced.

[0166] In summary, the rapid breaking device for arc faults described in the present application collects target working data (such as voltage and current signals) of the low-voltage direct-current system through the arc fault detection module. The target working data is analyzed. When an arc fault occurs, the voltage and current of the system will exhibit unique transient characteristics (such as waveform distortion, high-frequency pulsation, and abnormal mutation slope). Thus, a target fault detection result is obtained. Compared with the detection method based on radiation characteristics, the device analyzes the characteristics of the working electric signals of the low-voltage direct-current system, can avoid the interference difficulty of "radiation frequency overlap", does not need to rely on the radiation signal which is easily polluted by noise, but distinguishes based on the characteristic difference between arc and noise in the electric signal, thereby reducing misjudgment and improving the accuracy of arc fault detection.

[0167] Please refer to Figure 7 , Figure 7 is a flowchart of a rapid breaking method for arc faults provided by an embodiment of the present application. The method is applied to the rapid breaking device for arc faults described in the above embodiment. The method comprises the following steps:

[0168] S1, collecting target working data of the low-voltage direct-current system through the arc fault detection module; determining a target fault detection result according to the target working data; the target fault detection result includes one of the following: there is an arc fault, and there is no arc fault;

[0169] S2, generating a target breaking instruction by the control module when the target fault detection result includes the arc fault;

[0170] S3, performing a breaking operation according to the target breaking instruction by the fast breaking module to reduce the security risk.

[0171] In specific implementations, the fast breaking method for arc faults described in the embodiments of the present application can also include other implementation manners described in the fast breaking device for arc faults provided by the embodiments of the present application, which will not be described here.

[0172] The embodiments of the present application also provide a fast breaking system for arc faults, which includes any fast breaking device for arc faults as described in the above embodiments.

[0173] Please refer to Figure 8 , Figure 8 is a structural schematic diagram of an electronic device provided by the embodiments of the present application, which can include a processor, a memory, a communication interface and one or more programs, the processor, the memory and the communication interface can be connected with each other through a bus; the above one or more programs are stored in the above memory and configured to be executed by the above processor; in the embodiments of the present application, the program includes instructions for executing part or all steps of the fast breaking method for arc faults provided by the above method embodiments.

[0174] The embodiments of the present application also provide a computer readable storage medium, wherein the computer readable storage medium stores a computer program for electronic data exchange, the computer program causes a computer to execute part or all steps of any method recorded in the above method embodiments, and the computer includes an electronic device.

[0175] The embodiments of the present application also provide a computer program product, the computer program product includes a non-transitory computer readable storage medium storing a computer program, and the computer program is operable to cause a computer to execute part or all steps of any method recorded in the above method embodiments. The computer program product can be a software installation package, and the computer includes an electronic device.

[0176] It should be noted that, for each of the above method embodiments, in order to simply describe, it is expressed as a combination of a series of actions, but those skilled in the art should know that the present application is not limited by the order of the described actions, because according to the present application, certain steps can be performed in other order or simultaneously. Secondly, those skilled in the art should know that the embodiments described in the specification all belong to preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0177] In the above-described embodiments, the description of each embodiment focuses on different aspects, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0178] In several embodiments provided in the present application, it should be understood that the disclosed apparatus can be implemented by other manners. For example, the apparatus embodiments described above are only illustrative, for example, the division of the above units is only a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed units can be indirect coupling or communication connection through some interfaces, apparatuses or units, and can be electrical or other forms.

[0179] A person of ordinary skill in the art can understand that all or part of the processes in the above-described embodiments can be implemented by a computer program instructing relevant hardware, and the program can be stored in a computer readable storage medium. When the program is executed, the processes of the above-described embodiments can be included. The storage medium includes ROM, random access memory (RAM), magnetic disk or optical disk, and various storage media that can store program codes.

[0180] The steps of the method or algorithm described in the embodiments of the present application can be implemented in a hardware manner or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, and the software modules can be stored in RAM, flash memory, ROM, EPROM, electrically EPROM (EEPROM), register, hard disk, mobile hard disk, CD-ROM (compact disk-read only memory, CD-ROM) or any other form of storage medium well known in the art.

[0181] An exemplary storage medium is coupled to the processor, so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be an integral part of the processor. The processor and the storage medium can be located in an ASIC. In addition, the ASIC can be located in a terminal device or a management device. Of course, the processor and the storage medium can also exist as discrete components in the terminal device or the management device.

[0182] Those skilled in the art should be able to understand that, in one or more examples described above, the functions described in the embodiments of the present application can be implemented entirely or partially by software, hardware, firmware, or any combination thereof. When implemented by software, it can be implemented in the form of a computer program product entirely or partially. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are entirely or partially generated.

[0183] The computer described above can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center through wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) manner. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. integrated with one or more available media sets.

[0184] Among them, the available media can be magnetic media (such as floppy disk, hard disk, magnetic tape), optical media (such as digital video disc (DVD)), or semiconductor media (such as solid state disk (SSD)) and the like.

[0185] Each module / unit contained in each device / product described in the above embodiments can be a software module / unit, a hardware module / unit, or part of a software module / unit and part of a hardware module / unit.

[0186] For example, for each device, product applied to or integrated into a chip, each module / unit contained therein can be realized by hardware such as circuit, or at least part of the modules / units can be realized by software program running on a processor integrated in the chip, and the remaining (if any) part of the modules / units can be realized by hardware such as circuit; for each device, product applied to or integrated into a chip module, each module / unit contained therein can be realized by hardware such as circuit, and different modules / units can be located in the same component (for example, chip, circuit module, etc.) or different components of the chip module, or at least part of the modules / units can be realized by software program running on a processor integrated in the chip module, and the remaining (if any) part of the modules / units can be realized by hardware such as circuit; for each device, product applied to or integrated into a terminal device, each module / unit contained therein can be realized by hardware such as circuit, and different modules / units can be located in the same component (for example, chip, circuit module, etc.) or different components of the terminal device, or at least part of the modules / units can be realized by software program running on a processor integrated in the terminal device, and the remaining (if any) part of the modules / units can be realized by hardware such as circuit.

[0187] The above detailed description of the specific embodiments of the present application has further explained the purposes, technical solutions and beneficial effects of the embodiments of the present application. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made on the basis of the technical solutions of the embodiments of the present application shall be included in the protection scope of the embodiments of the present application.

Claims

1. A rapid disconnection device for arc faults, characterized in that, The device, applied to low-voltage DC systems, includes: an arc fault detection module, a control module, and a rapid disconnection module, wherein: The arc fault detection module is used to collect target operating data of the low-voltage DC system; determine the target fault detection result based on the target operating data; the target fault detection result includes one of the following: arc fault exists, arc fault does not exist; The control module is used to generate a target disconnection command when the target fault detection result includes the presence of an arc fault; The rapid segmentation module is used to perform segmentation operations according to the target segmentation instruction in order to reduce security risks; The target operating data includes target voltage data. In determining the target fault detection result based on the target operating data, the arc fault detection module is specifically used for: The target voltage data is segmented according to a first preset time interval to obtain m segments of voltage data; each segment of voltage data corresponds to a sampling time period; m is an integer greater than 1; Determine the average value corresponding to each voltage data segment in the m voltage data segments to obtain m average values; Determine the absolute value of the difference between any two adjacent average values ​​among the m average values ​​to obtain m-1 absolute values; Determine the maximum value corresponding to the m-1 absolute values; When the maximum value is greater than the first preset value, the target fault detection result is determined to include the presence of an electric arc fault; When the maximum value is not greater than the first preset value, determine the absolute value among the m-1 absolute values ​​that is greater than the second preset value, thus obtaining n absolute values; the second preset value is less than the first preset value; n is a positive integer less than or equal to m-1; determine the i-th voltage data segment corresponding to the n absolute values ​​in the m-th voltage data segment; i is an integer greater than n and less than or equal to m; determine the target fault detection result based on the i-th voltage data segment. Specifically, in determining the target fault detection result based on the i-segment voltage data, the arc fault detection module is used for: Determine the maximum voltage change value corresponding to each voltage data segment in the i-segment voltage data to obtain i maximum voltage change values; Fit each voltage data segment in the i segments to obtain i voltage lines; the horizontal axis of each voltage line is time, and the vertical axis is voltage value; Determine the slope of each voltage line among the i voltage lines to obtain i slopes; Determine a slopes greater than 0 and b slopes not greater than 0 from the i slopes; a and b are both natural numbers, and a + b = i; The target ratio is determined based on the a slopes and the b slopes; The target fault detection result is determined based on the i maximum voltage change values ​​and the target ratio.

2. The apparatus as claimed in claim 1, characterized in that, Regarding the acquisition of target operating data from the low-voltage DC system, the arc fault detection module is specifically used for: Determine the target arc fault set corresponding to the low-voltage DC system; Determine the target fault characteristic frequency based on the target arc fault set; The reference sampling frequency is determined based on the target fault characteristic frequency; Determine the equipment performance parameters corresponding to the arc fault detection module; Determine the target sampling frequency range corresponding to the device performance parameters; If the reference sampling frequency is within the target sampling frequency range, then the operating data of the low-voltage DC system is sampled according to the reference sampling frequency to obtain the target operating data; If the reference sampling frequency is not within the target sampling frequency range, then an intermediate value corresponding to the target sampling frequency range is determined, and the target sampling frequency is determined based on the intermediate value; the operating data of the low-voltage DC system is sampled according to the target sampling frequency to obtain the target operating data.

3. The apparatus as described in claim 2, characterized in that, In determining the target fault detection result based on the i maximum voltage change values ​​and the target ratio, the arc fault detection module is specifically used for: Obtain the starting sampling time corresponding to each of the i maximum voltage change values ​​to obtain i starting sampling times; The target voltage line is obtained by fitting the i maximum voltage change values ​​and the i initial sampling times; the horizontal axis of the target voltage line is time, and the vertical axis is voltage value. Determine the absolute value of the target slope corresponding to the target voltage line; When the absolute value of the target slope is greater than a third preset value, the target fault detection result is determined to include the presence of an electric arc fault; When the absolute value of the target slope is not greater than the third preset value, the target variance corresponding to the i maximum voltage change values ​​is determined; Determine the deviation between the target ratio and the fourth preset value to obtain the target deviation. When the target deviation is greater than a preset deviation, and / or the target variance is greater than a preset variance, the target fault detection result is determined to include the presence of an arc fault; When the target deviation is not greater than the preset deviation and the target variance is not greater than the preset variance, the target fault detection result is determined to include the absence of an arc fault.

4. The apparatus as described in claim 1 or 2, characterized in that, In determining the target fault detection result based on the target working data, the arc fault detection module is specifically used for: Obtain the preset training and test datasets; The first AI model is obtained by training the preset AI model using the training dataset. The first AI model is tested using the test dataset to obtain a first test result; Determine the first accuracy rate corresponding to the first test result; When the first accuracy rate is greater than or equal to a preset accuracy threshold, the target AI model is determined based on the first AI model; The target working data is input into the target AI model to obtain the target fault detection result.

5. The apparatus as described in claim 1 or 2, characterized in that, The device further includes a self-diagnostic module, which is specifically used for: Detect the target status data of the device; The target state of the device is determined based on the target state data; the target state includes: normal state and abnormal state. When the target state includes the abnormal state, a first abnormal command is transmitted to the control module; the first abnormal command is used to indicate that the device has an abnormality.

6. The apparatus as claimed in claim 5, characterized in that, The self-diagnosis module is also specifically used for: Generate simulated electric arc fault signals; The simulated arc fault signal is transmitted to the arc fault detection module; The detection results of the arc fault detection module for the simulated arc fault signal are obtained to obtain a first detection result; If the first detection result indicates the presence of an arc fault, then the arc fault detection module is determined to be in normal working condition. If the first detection result indicates that there is no arc fault, then the arc fault detection module is determined to be in an abnormal working state, and a second abnormal instruction is transmitted to the control module; the second abnormal instruction is used to indicate that the arc fault detection module is abnormal.

7. The apparatus as described in claim 1 or 2, characterized in that, The fast disconnect module includes a solid-state switch and a mechanical switch; the solid-state switch and the mechanical switch are connected in parallel; the fast disconnect module is disposed between the power supply and the load in the low-voltage DC system; When the low-voltage DC system is operating normally, both the solid-state switch and the mechanical switch are in the closed state, and the mechanical switch carries the operating current of the low-voltage DC system. In terms of performing the segmentation operation according to the target segmentation instruction, the fast segmentation module is specifically used for: In response to the target disconnection command, the solid-state switch is controlled to switch to the off state to cut off the current path; After the current path is cut off, the mechanical switch automatically disconnects in the absence of current.

8. A rapid disconnection system for arc faults, characterized in that, The system includes a rapid disconnection device for arc faults as described in any one of claims 1-7.

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