Arc detection device

Abstract

The present invention relates to an arc detection device comprising: a high-frequency signal sensing unit that detects a high-frequency signal from a current flowing through a power line; a signal strength sensing unit that senses the strength of the detected high-frequency signal; a voltage detection unit that detects a voltage change in the power line; and a control unit that detects zero crossing points, which are points in time at which a reference voltage is present, from the voltage change on the basis of the phase alternation of the voltage, detects a change in the intensity of the high-frequency signal in an interval between the detected zero crossing points, and detects a preset number of peaks from the change in the intensity of the high-frequency signal, the signal intensity values of the detected preset number of peaks are compared with a preset reference value to determine whether or not an arc occurs in the section.

Description

Technical Field

[0001] This invention relates to an arc detection device for detecting electric arcs. Background Technology

[0002] Generally, an electric arc (Arc) refers to an electric spark or a discharge phenomenon that occurs when a high voltage potential difference exists between positive and negative terminals, characterized by high current density. It is well known that such arcs can cause damage to wires or electrical products, break down wire insulation, cause poor connections, or indicate aging. Furthermore, they can ignite fires in the presence of flammable materials, thus becoming a major cause of electrical fires.

[0003] On the other hand, ordinary residual current circuit breakers (RCCBs) or overcurrent circuit breakers are primarily used to prevent leakage or short circuits. They can trip when a current exceeding a preset value is detected for a specified duration. However, arcing can occur even under low current conditions (below 3-5A). Therefore, it is difficult to detect arcs under such low current conditions or for durations below the specified time using RCCBs or overcurrent circuit breakers. In response, various countries are mandating the installation of arc-breaking circuit breakers capable of interrupting such arcs, and are actively conducting research on arc detection and interruption.

[0004] As part of this research, arc detection devices have emerged that detect noise in current signals and use the magnitude of the high-frequency components of the detected noise to sense the occurrence of an electric arc. However, current arc detection devices determine whether an arc has occurred based solely on the magnitude of specific high-frequency components detected from the noise of the current. Therefore, they have limitations in distinguishing between ordinary current noise and an electric arc, resulting in low accuracy in arc detection, such as mistaking noise for an electric arc or vice versa. Summary of the Invention

[0005] The problem to be solved

[0006] The purpose of this invention is to solve the aforementioned and other problems and provide an arc detection device that can more accurately determine whether an arc has occurred from the state of the current flowing in the circuit.

[0007] Technical solutions to the problem

[0008] To achieve the above or other objectives, according to one aspect of the present invention, an arc detection device according to an embodiment of the present invention is characterized in that it includes: a high-frequency signal sensing unit for detecting a high-frequency signal from a current flowing in an electric field line; a signal strength sensing unit for sensing the strength of the detected high-frequency signal; a voltage detection unit for detecting voltage changes in the electric field line; and a control unit for detecting zero-crossing points as time points with reference voltages from the voltage changes based on the phase of the voltage, detecting intensity changes of the high-frequency signal in the interval between the detected zero-crossing points, detecting a predetermined number of peaks from the intensity changes of the high-frequency signal, and comparing the signal strength values ​​of the detected predetermined number of peaks with a predetermined reference value to determine whether an arc has occurred in the interval.

[0009] One embodiment is characterized in that the control unit is configured to detect the number of signal intensities exceeding a preset threshold value from the intensity changes of the high-frequency signal detected in the interval, and detect the peaks of the preset number to determine whether the arc has occurred, or not detect the peaks of the preset number to determine that no arc has occurred in the interval.

[0010] One embodiment is characterized by further including an ammeter for measuring the current of the circuit; the control unit is configured to, based on the current measurement result, detect a predetermined number of peaks to determine whether an arc has occurred, based on whether the current change in the interval reaches or exceeds a predetermined ratio of the normal current, or not detect the predetermined number of peaks and determine that no arc has occurred in the interval.

[0011] One embodiment is characterized in that the control unit is configured to, among the detected pre-set number of peaks, identify two different peaks that are adjacent to the zero-crossing points that are different from each other in the interval as a first peak corresponding to the arc generation stage and a second peak corresponding to the arc extinction stage, respectively, and determine whether an arc has occurred in the interval based on the result of comparing the signal strength values ​​of the first peak and the second peak with a pre-set reference value.

[0012] One embodiment is characterized in that the control unit is configured to obtain high-frequency signal information including a plurality of intervals based on high-frequency signal samples collected from the signal strength sensing unit, and to determine whether the arc occurs based on whether there is an interval in which both the first peak and the second peak determined in each of the plurality of intervals included in the obtained high-frequency signal information are above the reference value.

[0013] To achieve the above or other objectives, according to one aspect of the present invention, an arc detection device according to an embodiment of the present invention is characterized by comprising: a high-frequency signal sensing unit for detecting a high-frequency signal from a current flowing in an electric field line; a signal strength sensing unit for sensing the strength of the detected high-frequency signal; a voltage detection unit for detecting voltage changes in the electric field line; and a control unit for detecting zero-crossing points, which are time points with reference voltages, from the voltage changes based on the phase alternation of the voltages; detecting intensity changes of the high-frequency signal from the interval between the detected zero-crossing points; detecting intensity deviations of each signal from other adjacent signals from the intensity changes of the high-frequency signal; and determining whether an arc occurs in the interval based on deviations exceeding a preset reference value among the detected deviations.

[0014] One embodiment is characterized in that the control unit includes a first peak with the largest deviation from a previous value and a second peak with the largest deviation from a subsequent value, and a control unit that determines whether an arc occurs in the interval based on the result of comparing the first deviation (which is the deviation between the first peak and the value before the first peak) and the second deviation (which is the deviation between the second peak and the value after the second peak) with the reference value.

[0015] One embodiment is characterized in that the control unit divides the interval into a first interval and a second interval, and detects the first peak and the first deviation in the first interval, and detects the second peak and the second deviation in the second interval.

[0016] One embodiment is characterized in that the control unit obtains high-frequency signal information including a plurality of intervals based on high-frequency signal samples collected by the signal strength sensing unit, and determines whether the arc occurs based on whether there is an interval in which both the first deviation and the second deviation are above the reference value among a plurality of first deviations and second deviations determined in each of the plurality of intervals included in the obtained high-frequency signal information.

[0017] One embodiment is characterized in that the control unit is configured to detect the number of signal intensities exceeding a preset threshold value from the intensity changes of the high-frequency signal detected in the interval, and determine whether an arc has occurred based on the deviation according to whether the detected number is greater than the preset number, or not detect the deviation and determine that no arc has occurred in the interval.

[0018] One embodiment is characterized by further including an ammeter for measuring the current of the circuit; the control unit, based on the current measurement result, determines whether an arc has occurred based on whether the current change in the interval reaches or exceeds a preset ratio of the normal current, or does not detect the deviation and determines that no arc has occurred in the interval.

[0019] To achieve the above or other objectives, according to one aspect of the present invention, an arc detection device according to an embodiment of the present invention is characterized by comprising: a high-frequency signal sensing unit for detecting a high-frequency signal from a current flowing in an electric field line; a signal strength sensing unit for sensing the strength of the detected high-frequency signal; a voltage detection unit for detecting voltage changes in the electric field line; an ammeter for measuring the current in the circuit; and a control unit for detecting zero-crossing points (time points with reference voltages) from the voltage changes based on the phase of the voltage, detecting intensity changes of the high-frequency signal from the interval between the detected first and second zero-crossing points, determining a first peak corresponding to the arc occurrence phase and a second peak corresponding to the arc extinction phase from the intensity changes of the high-frequency signal, dividing the interval into a plurality of arc intervals based on the first and second peaks, and determining whether an arc has occurred in the interval based on the current change pattern of each of the divided arc intervals.

[0020] One embodiment is characterized in that the control unit detects a predetermined number of peaks from the intensity changes of the high-frequency signal detected in the interval, and identifies two different peaks among the detected predetermined number of peaks that are adjacent to the zero-crossing points of the interval that are different from each other as the first peak and the second peak.

[0021] One embodiment is characterized in that the control unit divides the interval into a first interval and a second interval, and detects a first peak with the largest deviation from the previous value in the first interval, and a second peak with the largest deviation from the subsequent value in the second interval.

[0022] One embodiment is characterized in that the control unit determines the arc interval from the first zero-crossing point to the first peak as a first arc interval from the No Arc stage to the Arc Strike stage, determines the arc interval from the first peak to the second peak as a second arc interval corresponding to the Arc Conduct stage, and determines the arc interval from the second peak to the second zero-crossing point as a third arc interval from the Arc Quenches stage to the No Arc stage.

[0023] One embodiment is characterized in that, when the current reduction in the first arc interval and the third arc interval is at or above a predetermined ratio of the normal current, and the current reduction in the second arc interval is less than the current reduction in the first arc interval and the third arc interval, the control unit determines that an arc has occurred in the interval.

[0024] One embodiment is characterized in that the ammeter is a low-frequency current transformer (LFCT) sensor.

[0025] One embodiment is characterized in that the high-frequency signal sensing unit is a high-frequency current transformer (HFCT) sensor.

[0026] One embodiment is characterized by further including a blocking unit for disconnecting the power line and the internal circuit connected to the load, the control unit increasing or decreasing the trip count according to whether the arc occurs, and outputting a trip control signal to the blocking unit for driving the blocking unit when the increased or decreased trip count reaches a preset value.

[0027] One embodiment is characterized in that if the determination result of whether an arc has occurred is that no arc has occurred, the control unit reduces the trip count based on whether a preset condition is met.

[0028] One embodiment is characterized in that the preset condition is satisfied when it is determined that no electric arc has occurred for a specified time.

[0029] Invention Effects

[0030] The effects of the arc detection device of the present invention will now be explained.

[0031] According to at least one embodiment of the present invention, the present invention determines whether an electric arc is detected based on the characteristics of the periodic pattern of the occurrence and extinction of an electric arc caused by the flow of current, thereby enabling a more precise determination of whether an electric arc has occurred.

[0032] Furthermore, when an electric arc is detected, the present invention only drives the blocking part to disconnect the internal circuit and the power line when the number of detected arcs reaches a preset number or more. This prevents accidental disconnection of the internal circuit and the power line due to temporary noise that may be mistaken for an electric arc.

[0033] Furthermore, even when an electric arc is detected, the present invention can reduce the number of arc occurrences if the measured value for arc detection, such as the periodic pattern of the current signal, meets a preset mitigation control condition. Therefore, the present invention dynamically increases or decreases the number of arc occurrences used to drive the blocking part, and activates the blocking part based on the increased or decreased number of arc occurrences, thereby ensuring the reliability of driving the blocking part based on arc detection. Attached Figure Description

[0034] Figure 1 This is a block diagram illustrating the structure of an arc detection device according to an embodiment of the present invention.

[0035] Figure 2 This is a flowchart illustrating the process by which the arc detection device of an embodiment of the present invention detects an arc and controls the driving of the blocking part based on the arc detection result.

[0036] Figure 3 This is an example diagram used to illustrate the periodic characteristics of a high-frequency current signal generated in the event of an electric arc.

[0037] Figure 4 This is a flowchart illustrating the process of determining whether an electric arc is detected based on the zero-crossing point and the peak near the zero-crossing point in the arc detection device according to an embodiment of the present invention.

[0038] Figure 5 It is shown according to the description Figure 4 An example diagram illustrating the action process of detecting an electric arc based on a peak near the zero point.

[0039] Figure 6 This is a flowchart illustrating the process of determining whether an arc is detected based on the deviation of each interval divided according to the zero-crossing point of the current in the arc detection device of this embodiment of the invention.

[0040] Figure 7 According to the description Figure 6 An example diagram illustrating the process of detecting an electric arc based on the deviation of each interval divided with the zero-crossing point as the reference.

[0041] Figure 8 This is a flowchart of the process by which the arc detection device of this invention reduces the trip count when the arc detection result meets the preset conditions.

[0042] Figure 9 This is an example diagram illustrating an embodiment of the arc detection device of the present invention, which is further provided with an LFCT for detecting current.

[0043] Figure 10 It is shown that Figure 9 The flowchart shows the operation process of the control unit of the arc detection device, which determines whether an arc has occurred based on the current changes in each interval corresponding to the various stages of arc occurrence and extinction. Detailed Implementation

[0044] It should be noted that the technical terms used in this specification are for illustrative purposes only and are not intended to limit the invention. Furthermore, unless the context clearly indicates otherwise, singular expressions used in this specification include plural expressions. The suffixes "module" and "part" used in the following description for the constituent elements are assigned or used interchangeably only for ease of writing and do not inherently carry a distinguishing meaning or function.

[0045] In this specification, terms such as “constituting” or “including” should not be construed as including all the constituent elements or steps described in the specification, but should be construed as excluding some of the constituent elements or steps, or including additional constituent elements or steps.

[0046] In addition, in the process of describing the technology disclosed in this specification, when it is determined that a detailed description of the relevant known technology would obscure the essence of the technology disclosed in this specification, a detailed description thereof is omitted.

[0047] The accompanying drawings are merely for ease of understanding of the embodiments disclosed in this specification and should not be construed as limiting the technical ideas disclosed herein. They should be understood to encompass all modifications, equivalents, and substitutions included within the scope of this specification's ideas and techniques. Furthermore, combinations of embodiments, in addition to the individual embodiments described below, are also considered modifications, equivalents, and substitutions included within the scope of this invention's ideas and techniques.

[0048] first, Figure 1 This is a block diagram illustrating the structure of the arc detection device 10 according to an embodiment of the present invention.

[0049] Reference Figure 1 The arc detection device 10 of this embodiment can be configured between the power line of the power grid and the internal line connected to the load. Additionally, it can be connected to a blocking part 30 that disconnects the internal line from the power line by disconnecting the contacts of the internal line and the power line, and outputs a trip control signal to control the operation of the blocking part 30 based on the arc detection result detected from the power line.

[0050] On the other hand, such as Figure 1As shown, the arc detection device 10 of this embodiment may include an HFCT (High Frequency Current Transformer) 110 for detecting high frequency current signals of electric power lines, a filtering unit 120 for filtering frequencies, a signal strength sensing unit (Power detector) 130 for detecting the signal strength of high frequency current signals, an amplification unit 140 for amplifying the signal level of the high frequency current signals sensed by the signal strength sensing unit 130 to a signal size recognizable by the control unit 100, and a control unit 100.

[0051] Additionally, the arc detection device 10 may include a voltage detection unit 150 for detecting voltage changes in the circuit between the power line and the internal circuitry, and may include an output unit 170 for outputting the arc detection result to the control unit 100 or a communication unit 180 for transmitting the arc detection result to a pre-set device.

[0052] Figure 1 The components shown are not essential components for realizing the arc detection device 10. Therefore, the arc detection device 10 described in this specification may have more or fewer components than those listed above.

[0053] More specifically, the HFCT110 in the aforementioned components may be a sensor for detecting high-frequency signals (hereinafter referred to as high-frequency current signals) of current flowing through the power line into the internal circuit connected to the load or from the internal circuit into the power line. The HFCT110 may include at least one sensor for detecting high-frequency signals generated during partial discharge or arcing.

[0054] Furthermore, the filtering unit 120 can be a filter that filters specific frequencies using a frequency-domain masking method. Here, the specific frequency can be a frequency corresponding to noise generated during the operation of household noise or loads, or electromagnetic noise (EMC (Electromagnetic Compatibility) noise). That is, the filtering unit 120 can function as a filter that filters signals in at least one pre-specified frequency band that are different from each other, and can be a filter that removes noise in a pre-known frequency band, such as household noise, load drive noise, electromagnetic noise, etc.

[0055] On the other hand, the signal strength sensing unit 130 can detect the intensity of the high-frequency current signal detected by the HFCT 110. For example, the signal strength sensing unit 130 can convert the high-frequency current signal detected by the HFCT 110 into a voltage signal according to its magnitude. In this case, the high-frequency current signal converted into a voltage signal can be an analog signal.

[0056] On the other hand, the control unit 100 (e.g., a Micro Controller Unit, MCU) connected to the signal strength sensing unit 130 may include an analog-to-digital converter (ADC) for converting the analog high-frequency current signal output from the signal strength sensing unit 130 into a digital signal. Thus, the control unit 100 can obtain digital signals having values ​​that differ from each other based on the signal strength of the high-frequency signal (high-frequency current signal) of the current detected by the HFCT 110.

[0057] Alternatively, the analog-to-digital converter (ADC) can also be provided within the signal strength sensing unit 130. In this case, the signal strength sensing unit 130 can output a digital signal corresponding to a high-frequency current signal converted into an analog form of the voltage signal. Furthermore, the output digital signal can be input to the control unit 100. Alternatively, the ADC can also be implemented by an additional component disposed between the signal strength sensing unit 130 and the control unit 100. In this case, the ADC can convert the analog signal output from the signal strength sensing unit 130 into a digital signal and output it to the control unit 100.

[0058] Furthermore, the amplification unit 140 can receive digital signals input from the signal strength sensing unit 130 and amplify the received digital signals to a level that can be recognized by the control unit 100. Here, the amplification unit 140 can be an inverting amplifier that inverts the phase of the input signal and amplifies the inverted signal phase due to a voltage gain with a negative (-) value, or a non-inverting amplifier that maintains the phase of the input signal while only amplifying its magnitude due to a voltage gain with a positive (+) value.

[0059] On the other hand, the voltage detection unit 150 can detect voltage changes in the circuit or power line (hereinafter collectively referred to as circuit) through which current flows from the power line to the internal circuit or from the internal circuit to the power line.

[0060] In this case, if the current flowing in the circuit is a single-phase current, the current flowing between the power line and the internal circuit can be a current whose voltage phase alternates periodically with the period of the single-phase current. Therefore, in the circuit, the positive (+) voltage and the negative (-) voltage change periodically, and this voltage change can be detected by the voltage detection unit 150 and provided to the control unit 100.

[0061] On the other hand, the control unit 100 can control the various connected components and the overall operation of the arc detection device 10. For example, the control unit 100 can detect the time points of phase transition of the voltage from the voltage changes detected by the voltage detection unit 150, that is, the time points when the voltage phase has a reference voltage (e.g., 0V) at 0 degrees and 180 degrees, i.e., the zero-crossing point. In this case, centered on the zero-crossing point, the voltage of the circuit can transition from a state with a positive (+) voltage to a state with a negative (-) voltage.

[0062] Furthermore, the control unit 100 can receive the high-frequency current signal amplified by the amplification unit 140. It can also detect changes in the intensity of the high-frequency current signal over time. In this case, the control unit 100 can determine whether an electric arc occurred during the half-cycle based on the zero-crossing point detected by the voltage detection unit 150 and the half-cycle of the single-phase current flowing from the power line into the internal line or from the internal line into the power line. Furthermore, it can determine whether an electric arc occurred during the half-cycle based on the detected change in the intensity of the high-frequency current signal during the half-cycle.

[0063] Therefore, the control unit 100 can determine whether an electric arc has occurred based on the structural characteristics of the arc signal. This determination can be based on the periodic characteristics of the arc's occurrence and extinguishing between the two contacts where the arc occurs.

[0064] As an example, in the event of insulation damage or breakdown between adjacent circuits, or circuit cracking due to aging or damage, a voltage difference will be generated between the locations of the insulation damage or breakdown, or between the two contacts (hereinafter referred to as arc contacts) of the circuit disconnected by the crack. This results in a discharge phenomenon caused by the generated voltage difference, i.e., an arc. Since this arc is caused by the voltage difference between the arc contacts, it can have a periodic characteristic of arcing and extinguishing as the voltage flowing through the circuit changes periodically, similar to single-phase current.

[0065] The periodic characteristics of the generation and extinction of this electric arc are described, which include the following phases: from a state where no arc is generated due to a small voltage difference between the arc contacts (No Arc stage), to the arc ignition stage where an arc begins to occur at the arc contacts as the voltage difference between the arc contacts increases; the arc conduction stage where current is conducted between the arc contacts as the voltage difference between the arc contacts reaches its maximum value through the current discharged from the arc contacts; and the arc quenching stage where the arc is extinguished as the voltage between the arc contacts decreases.

[0066] On the other hand, the size of the detected arc can vary depending on the voltage change during the various stages of the arc's occurrence and extinction, namely the arc-free stage, the arc ignition stage, the arc conduction stage, and the arc extinction stage.

[0067] For example, the arc ignition stage and the arc extinguishing stage can be the stages where the arc occurs most intensely between the arc contacts. Furthermore, the arc conduction stage, where current flows between the arc contacts due to arc discharge, may be a stage where the voltage difference between the two arc contacts is at its maximum, but arc generation is relatively low. Conversely, the arc-free stage can be a stage where no arc occurs or the arc is extinguished, possibly the stage with the least arc generation. Moreover, the larger the arc generation, the stronger the high-frequency current signal. Therefore, while the arc generates its maximum value during the arc ignition and arc extinguishing stages, a smaller arc can occur during the arc conduction stage. Conversely, almost no arc occurs in the arc-free state.

[0068] On the other hand, as an electric arc is generated, the signal strength sensing unit 130 can sense a high-frequency current signal corresponding to the size of the generated electric arc. Furthermore, the control unit 100 can detect changes in the size of the generated electric arc based on changes in the intensity of the high-frequency current signal sensed by the signal strength sensing unit 130.

[0069] Furthermore, based on the change in the magnitude of the high-frequency current signal over time and the zero-crossing point detected by the voltage detection unit 150, it can be determined whether the change in the magnitude of the high-frequency current signal, which corresponds to the voltage change in the circuit, matches the periodic characteristics of the arc, i.e., the arc's occurrence and extinction mode. And, based on the determination result, it can be determined whether an arc has occurred.

[0070] Alternatively, if a pattern of high-frequency current signal magnitude change corresponding to the occurrence and extinguishing of an electric arc is detected, the control unit 100 can check whether a predetermined number of such a pattern of high-frequency current signal magnitude change corresponding to the occurrence of the electric arc has been detected. Furthermore, based on the check results, it can be determined whether the detected pattern of change is caused by temporary noise or by the occurrence of an electric arc. If it is determined that an electric arc has occurred, a trip control signal for driving the blocking unit 30 is output to the blocking unit 30, thereby interrupting the power supply by disconnecting the circuit. Therefore, it is possible to prevent hazards such as fires caused by the generation of an electric arc in advance.

[0071] On the other hand, in the case where a trip control signal is output based on the detection of an electric arc, the control unit 100 can output a warning signal notifying that an electric arc has occurred via the output unit 170. In this case, the output unit 170 can be configured to display the electric arc occurrence status visually and audibly. Therefore, the output unit 170 may include at least one of a speaker and a display unit.

[0072] Alternatively, the control unit 100 may include a communication unit 180 for transmitting the reminder signal to a pre-defined server or a pre-defined device. In this case, the pre-defined device may be a pre-designated user terminal, such as a mobile phone, smartphone, laptop computer, PDA (personal digital assistant), slate PC, tablet PC, ultrabook, smartwatch, smart glasses, HMD (head-mounted display) wearable device, etc.

[0073] Figure 2 This is a flowchart illustrating the operation process of the arc detection device 10 of the above-described embodiment of the present invention detecting an arc and controlling the driving of the blocking part 30 based on the arc detection result. Figure 3 This is an example diagram used to illustrate the periodic characteristics of a high-frequency current signal generated in the event of an electric arc.

[0074] First, refer to Figure 2 In this embodiment of the invention, the control unit 100 of the arc detection device 10 can first obtain the signal detected by the signal strength sensing unit 130, i.e., the high-frequency current signal sample, from the HFCT 110 (S200). Here, the high-frequency current signal sample can be collected according to the collection period of the HFCT 110.

[0075] In step S200, the control unit 100 can determine whether sufficient high-frequency current signal samples have been collected to determine whether an arc has occurred. For example, the control unit 100 can connect the collected high-frequency current signal samples in chronological order and determine whether the length of the high-frequency current signal generated by connecting a plurality of high-frequency current signal samples corresponds to a preset time. Furthermore, if a high-frequency current signal of a length corresponding to the preset time has been generated, it can be determined that a sufficient number of high-frequency current signal samples, i.e., a high-frequency current signal, have been collected to determine whether an arc has occurred.

[0076] On the other hand, as described above, the present invention can determine whether an electric arc has occurred based on the periodic pattern of its occurrence and extinction. Therefore, the high-frequency current signal used to determine whether the electric arc has occurred can be a high-frequency current signal with a length sufficient to analyze the periodic pattern of the electric arc's occurrence and extinction.

[0077] Here, as described above, the arc's occurrence and extinction are characterized by a periodic pattern consisting of an arc-free phase, an arc ignition phase, an arc conduction phase, and an arc extinction phase. In this case, although the arc conduction phase has the maximum voltage difference between the two arc contacts, most of the current flows through the arc contacts as the current conducts, thus reducing the arc size. Conversely, in the arc ignition and extinction phases, the voltage difference between the two arc contacts decreases, and most of the current between the arc contacts is in a discharging state, thus allowing for a state of intense arc generation.

[0078] Figure 3 This is an example diagram used to illustrate the characteristics of a high-frequency current signal that exhibits a periodic pattern in the event of an electric arc.

[0079] First, in the event of insulation damage or breakdown occurring in adjacent circuits that are not directly connected, the location of the damage or breakdown can become a contact point where an electric arc can occur. Similarly, in the event of a crack in a circuit due to aging or damage, the ends of the crack can also become contacts where an electric arc can occur. Hereinafter, the location where an electric arc occurs due to the aforementioned insulation damage, breakdown, or crack will be referred to as an arc-forming contact, or an arc contact.

[0080] Reference Figure 3From the perspective of the current characteristics of alternating current, at the point of transition from positive to negative voltage, i.e., near the zero-crossing point, the voltage difference between adjacent arcing contacts can decrease. Therefore, an arc may not occur. In this stage where no arc occurs between the arcing contacts, i.e., the arc-free stage 310, since no arc occurs, the high-frequency current signal based on the occurrence of the arc is almost undetectable.

[0081] However, based on the characteristics of alternating current in a single-phase current, the supplied voltage can gradually increase as it passes through the zero-crossing point. This allows the voltage difference between the arc contacts to gradually increase. Furthermore, if a voltage difference exceeding a predetermined level is formed, a discharge, i.e., an arc, can occur due to this voltage difference. Therefore, as the arc-free phase 310 passes through the zero-crossing point, the increase in voltage difference can increase the occurrence, intensity, and size of the arc. Thus, a phase where a stronger high-frequency current signal is generated can proceed, i.e., the arc ignition phase 320.

[0082] On the other hand, if the voltage difference between the arc contacts reaches a predetermined level or higher as the circuit voltage increases, energization can occur between the two arc contacts due to arc discharge. In this case, the size of the arc decreases as current flows between the arc contacts. Figure 3 As shown, as the size of the electric arc decreases, it can enter the arc conduction stage 330 where the high-frequency current signal decreases.

[0083] If, based on the characteristics of alternating current in a single-phase current, the voltage decreases again during the arc conduction stage 330, an arc discharge large enough to initiate energization may not form between the arc contacts on both sides. In this case, the current flowing as the arc contacts become conductive is converted back into an arc, and the intensity and size of the arc can increase again. That is, the arc extinction stage 340 can then commence.

[0084] On the other hand, during the arc extinction stage 340, according to the characteristics of alternating current, as the voltage decreases and approaches the zero-crossing point, the voltage difference between the arc contacts can again approach 0. Therefore, the arc may not recur, and the process enters the arc-free stage 310.

[0085] That is, based on the characteristic of alternating current where the positive or negative voltage gradually increases as it passes through the zero-crossing point, and then decreases again to the zero-crossing point after passing through the peak position, the electric arc can go through four stages: an arc-free stage 310, an arc ignition stage 320, an arc conduction stage 330, and an arc extinction stage 340, thus generating and extinguishing the arc. Furthermore, the electric arc is not temporary noise and can therefore continue to repeat. Therefore, the pattern of the four stages formed during the first cycle 301 can be repeated again in the second cycle 302.

[0086] Therefore, as Figure 3 As explained, in the event of an electric arc, the high-frequency current signal detected by the HFCT110 exhibits a recurring periodic pattern consisting of an arc-free phase 310, an arc ignition phase 320, an arc conduction phase 330, and an arc extinction phase 340. Furthermore, since the arc continues to occur in the event of insulation breakdown, damage, or circuit cracks, this periodic pattern can continuously repeat according to the voltage change period based on the characteristics of the alternating current.

[0087] Furthermore, based on the characteristics of the alternating current, the voltage change in the circuit can occur periodically each time the voltage phases alternate (e.g., when the voltage phase is 0 degrees or 180 degrees), i.e., each time it crosses a zero point. On the other hand, considering the characteristics of the alternating current, the time between zero points is equivalent to half a cycle. Therefore, when a high-frequency current signal sample equivalent to half a cycle of the alternating current is collected, the control unit 100 can determine that a high-frequency current signal with a length sufficient to analyze the periodic pattern of arc occurrence and extinction has been received.

[0088] On the other hand, if it is determined that a sufficiently long high-frequency current signal has been collected, the control unit 100 can first determine whether it is a suspicious state where arcing is suspected or a normal state where arcing is not suspected (S202). For example, the control unit 100 can detect whether there is a signal strength exceeding a preset threshold value from the obtained high-frequency current signal, and if the number of signal strengths exceeding the threshold value is less than the preset number, it can be determined that it is a normal state where arcing is not suspected. However, if the number of signal strengths exceeding the threshold value is more than the preset number, it can be determined that it is a suspicious state where arcing is suspected.

[0089] Alternatively, the control unit 100 may detect the magnitude of the current flowing in the power line and internal circuitry in step S202, and determine whether an arcing is suspected based on the detected current magnitude. For example, in the event of an arcing, the current decreases due to the arcing, and therefore the current value may change by more than a preset level (e.g., 5%) in the event of an arcing.

[0090] Therefore, if the current detected from the circuit between the power line and the internal circuit changes by more than 5%, the control unit 100 can determine that it is a suspected state of arcing. However, if the change in current detected from the circuit between the power line and the internal circuit is less than 5%, it can be determined that it is a normal state of no suspicion of arcing. In this case, the arc detection device 10 of this embodiment may also be provided with a current sensor for detecting the current from the circuit.

[0091] In addition to the amount of current change, the control unit 100 can also determine whether the current is in a normal state based on the periodicity of the current change. In this case, the control unit 100 can determine whether the current change changes periodically with respect to the zero-crossing point of the alternating current characteristics. That is, if the current change has a periodic characteristic where it is minimum near the zero-crossing point and maximum between the zero-crossing points, the control unit 100 can determine it as a suspicious state where an arc is suspected. Conversely, if the current change does not have a periodic characteristic, the control unit 100 can determine it as a normal state where an arc is not suspected.

[0092] On the other hand, in step S202, the control unit 100 may also determine whether a state is normal based on a combination of two or more of the methods described above for determining whether a state is normal. For example, the control unit 100 may determine a state as normal only if the change in current is less than a preset level (e.g., 5%) and the change in current does not exhibit periodic characteristics. However, if the change in current is 5% or more, or even if the change in current is less than 5% but the current changes periodically (based on the zero-crossing point), it may be determined as a suspicious state where arcing is suspected. Conversely, if the change in current is less than 5% and the change in current does not exhibit periodic characteristics based on the zero-crossing point, it may be determined as a normal state where arcing is not suspected.

[0093] If the judgment result of step S202 is that the situation is normal and there is no suspicion of an electric arc, the control unit 100 can continue to collect samples of the high-frequency current signal by executing step S200 again. However, if the judgment result of step S202 is that the situation is not normal, i.e., there is suspicion of an electric arc, the control unit 100 can determine whether an electric arc has occurred based on the peak or deviation of the high-frequency current signal detected between each zero crossing point (S204).

[0094] For example, in step S204, the control unit 100 can detect a predetermined number of peaks in the high-frequency current signal values ​​between the first zero-crossing point and the second zero-crossing point, in descending order of value. Furthermore, based on the detected peaks and the positions of the zero-crossing points, one of the detected peaks is identified as the peak corresponding to the arc ignition stage, and the other peak is identified as the peak corresponding to the arc extinguishing stage.

[0095] As an example, when the preset number is two, the control unit 100 can detect the two peaks in descending order of the intensity of the high-frequency current signal. Here, the first zero-crossing point and the second zero-crossing point are zero-crossing points that are adjacent to each other in time sequence, and the occurrence of the first zero-crossing point may be earlier than the occurrence of the second zero-crossing point.

[0096] Furthermore, the control unit 100 can identify peaks close to the first zero-crossing point as peaks in the arc ignition stage and peaks close to the second zero-crossing point as peaks in the arc extinguishing stage. In addition, the control unit 100 can determine whether an arc has occurred based on the detected peaks.

[0097] On the other hand, the above explanation uses a preset quantity of two as an example, but the preset quantity can certainly be two or more. For example, when the preset quantity is three, the control unit 100 can detect three peaks in descending order of the intensity of the high-frequency current signal. Furthermore, the control unit 100 can identify the peak near the first zero-crossing point as the peak of the arc ignition stage and the peak near the second zero-crossing point as the peak of the arc extinguishing stage. However, in the following explanation, we will assume a preset quantity of two for ease of explanation.

[0098] The following is for reference Figure 4 and Figure 5 The operation process of step S204, which determines whether an electric arc has occurred based on the peak of the high-frequency current signal detected between the zero-crossing point and the zero-crossing point, will be explained in more detail.

[0099] Alternatively, the control unit 100 may determine whether an arc has occurred in step S204 based on the deviation of the high-frequency current signal intensity near the zero-crossing point. For example, the control unit 100 may detect the peak with the largest first deviation from the previous value and the peak with the largest second deviation from the subsequent value, and determine the detected peaks as the arc ignition peak and the arc extinguishing peak, respectively. Furthermore, the occurrence of an arc can also be determined based on the first deviation and the second deviation. This is to detect the occurrence of an arc based on the periodic characteristics of the arc, which shows a sharp increase in arc intensity (first deviation) when transitioning from the arc-free stage to the arc ignition stage, and a sharp decrease in arc intensity (second deviation) when transitioning from the arc extinguishing stage to the arc-free stage.

[0100] The following is for reference Figure 6 and Figure 7 The operation process of step S204, which determines whether an electric arc has occurred based on the deviation of the high-frequency current signal detected near the zero crossing point, will be explained in more detail.

[0101] On the other hand, if the arc detection process in step S204 is completed, the control unit 100 can check whether an arc has occurred (S206). Furthermore, the driving of the blocking unit 30 can be controlled based on whether the arc has occurred.

[0102] However, electric arcs can also occur temporarily due to surge noise, switching noise, or load transients, and can extinguish themselves naturally within a short time. If the power supply to the load is limited by driving the blocking section 30 in such cases, unnecessary economic losses may occur. Therefore, the control unit 100 of the arc detection device 10 can also drive the blocking section 30 only when the number of arc occurrences reaches a preset number, thereby ensuring the reliability of the blocking section 30's operation.

[0103] Therefore, if the check result of step S206 indicates that an electric arc has been detected, the control unit 100 can increment the trip count for driving the blocking unit 30 by 1 (S208). Conversely, if the check result of step S206 indicates that no electric arc has been detected, the trip count can be decremented by 1 (S210). In this case, the minimum value of the trip count can be 0, and if the trip count is already at the minimum value of 0, the control unit 100 can maintain the current trip count.

[0104] Alternatively, the control unit 100 may decrement the trip count by 1 only if the check result of step S206 meets a preset condition. That is, even if an arc is not determined to have occurred, if the high-frequency current signal has characteristics similar to the occurrence of an arc, the control unit 100 may maintain the current state without decrementing the trip count. Thus, even if it is determined that no arc has occurred, the trip count may not be decremented. In this case, the trip count may not be decremented, and the trip count may be incremented again based on the determination result of whether an arc has occurred based on the subsequently collected high-frequency current signal.

[0105] Reference Figure 8 The operation process of the control unit 100, as described above, reducing the trip count based on whether a preset condition is met will be explained in detail.

[0106] On the other hand, in steps S208 or S210, if the trip count has been increased or decreased, the control unit 100 can check whether the increased or decreased trip count exceeds a preset value for driving the blocking unit 30 (S212). Furthermore, if the check in step S212 indicates that the increased or decreased trip count does not exceed the preset value, step S200 is executed again to obtain a high-frequency current signal for detecting the arc signal from the collected high-frequency current signal samples. In this case, the process can be repeated... Figure 2The action process following step S200 as described in the text.

[0107] However, if the check result of step S212 shows that the trip count after adjustment exceeds the preset value, the control unit 100 can output a control signal, i.e., a trip control signal, to the blocking unit 30 to drive the blocking unit 30. In this way, the blocking unit 30 can be driven according to the trip control signal, thereby disconnecting the power line and the internal wiring connected to the load. This cuts off the current supply, thus extinguishing the arc and preventing electrical fires caused by arcing. When the trip control signal is output as described above, the trip count can be initialized.

[0108] On the other hand, if the check result in step S212 shows that the trip count exceeds the preset value, the control unit 100 can output a warning signal indicating the occurrence of an arc via the output unit 170 before outputting the trip control signal. Alternatively, the warning signal can be transmitted to a server or a preset device via the communication unit 180.

[0109] In this case, the control unit 100 may output the trip control signal to the blocking unit 30 only after a preset time has elapsed following the output of the reminder signal, or only when a trip control signal is received from the server or a preset device. This is to notify users or servers in advance of a trip caused by an arc, and to respond to sudden power outages, thereby minimizing losses caused by power outages such as data loss or equipment damage.

[0110] on the other hand, Figure 4 This is a flowchart illustrating the process by which the arc detection device 10 of this embodiment determines whether an arc is detected based on the zero-crossing point of the current and the peak near the zero-crossing point, as described above. Figure 5 It is shown according to the description Figure 4 An example diagram illustrating the action process of detecting an electric arc based on a peak near the zero point.

[0111] Reference Figure 4 The control unit 100 of the arc detection device 10 in this embodiment of the invention can first start from the... Figure 2 The high-frequency current signal obtained in step S200 is used to detect the position corresponding to the zero-crossing point (ZCP) according to the voltage change of the circuit (S400). In this case, the obtained high-frequency current signal can be formed into at least one high-frequency current signal sample in chronological order, including at least two zero-crossing points. Thus, the control unit 100 can detect the time point of voltage polarity reversal, i.e., the time point corresponding to the zero-crossing point, based on the voltage change detected during the time period corresponding to the high-frequency current signal.

[0112] If a zero-crossing point is detected in step S400, the control unit 100 can detect two peaks in the high-frequency current signals between the zero-crossing point and the zero-crossing point, in descending order of value, i.e., signal strength (S402).

[0113] Furthermore, based on whether a peak occurs after each zero crossing or whether a zero crossing occurs after a peak, the detected peaks can be identified as peaks of different arc stages (S404).

[0114] For example, the control unit 100 can determine the peak of the high-frequency current signal that occurs first after the zero-crossing of the two peaks as the peak of the arc ignition stage (hereinafter referred to as the arc ignition peak). Conversely, if a zero-crossing occurs after a peak, the peak can be determined as the peak of the arc extinguishing stage (hereinafter referred to as the arc extinguishing peak). That is, in step S402, the control unit 100 can detect two peak values ​​in descending order from the first zero-crossing and the second zero-crossing according to the time sequence, and then in step S404, it can determine the peak adjacent to the first zero-crossing as the arc ignition peak, and the peak adjacent to the second zero-crossing as the arc extinguishing peak.

[0115] Figure 5 This is a diagram illustrating an example of determining the arc ignition peak and arc extinction peak based on the zero-crossing point.

[0116] Reference Figure 5 , Figure 5 These are curves 570 and 560, representing the changes in signal strength of the high-frequency current signal and the voltage changes detected by the circuit. Furthermore, an example of obtaining a high-frequency current signal consisting of four intervals between five zero-crossing points (ZCPs) 551, 552, 553, 554, and 555 is shown. Additionally, Figure 5 The amplification section 140 uses an inverting amplifier, and the greater the strength of the high-frequency current signal, the smaller the value can be.

[0117] Reference Figure 5 First, the control unit 100 can detect a predetermined number (e.g., two) of peaks from the high-frequency current signal 560 detected in the first interval, i.e., the interval between the first ZCP551 and the second ZCP552, in descending order of signal strength. In this case, due to the characteristics of the inverting amplifier, a second peak 521 with the minimum value and a first peak 511 with the second minimum value can be detected. Furthermore, the control unit 100 can determine the first peak 511, which is the peak that occurs first after the zero-crossing point, as the arc ignition peak, and the peak that occurs after the zero-crossing point, i.e., the second peak 521, as the arc extinguishing peak, from the detected peaks 511 and 521.

[0118] That is, the control unit 100 can determine the first peak 511, which occurs first in time and is adjacent to the first zero-crossing point 551 of the high-frequency current signal, as the arc ignition peak, and the second peak 521, which occurs last in time and is adjacent to the second zero-crossing point 552 of the high-frequency current signal, as the arc extinguishing peak.

[0119] Furthermore, the control unit 100 can detect two peaks in descending order of value within each interval between zero crossings in a similar manner. Moreover, the peaks detected in chronological order can be identified as the arc ignition peak and the arc extinguishing peak. Thus, in the aforementioned... Figure 5 In the case of the high-frequency current signal 560 shown, among the two peaks detected from the interval between each zero crossing point, the first peaks 511, 512, 513, and 514 can be identified as arc ignition peaks, while the subsequent peaks 521, 522, 523, and 524 can be identified as arc extinguishing peaks.

[0120] Here, if the arc ignition peak and the arc extinction peak are determined from the interval between the zero-crossing point and the zero-crossing point, the control unit 100 can divide the interval between the zero-crossing point and the zero-crossing point into intervals corresponding to each stage of arc generation and extinction based on the determined peaks.

[0121] As an example, the control unit 100 can consider the interval 500 from the zero-crossing point to the arc ignition peak as the interval from the arc-free stage to the arc ignition stage. Furthermore, the interval 501 from the arc ignition peak to the arc extinguishing peak can be considered as the interval corresponding to the arc conduction stage. Moreover, the interval 502 from the arc extinguishing peak to the next zero-crossing point can be considered as the interval between the arc extinguishing stage and the arc-free stage.

[0122] On the other hand, if the arc ignition peak and arc extinguishing peak are determined from the interval between each zero-crossing point in step S404, the control unit 100 can determine whether an arc has occurred based on the determined peak values ​​of the arc ignition peak and arc extinguishing peak (S406). In this case, the control unit 100 can compare the determined peak values ​​of the arc ignition peak and arc extinguishing peak with each preset reference value. Furthermore, it can detect whether there is an interval between each zero-crossing point where both the arc ignition peak and arc extinguishing peak are above the reference value.

[0123] Furthermore, if both the arc ignition peak and the arc extinguishing peak exist within a range above the reference value, the control unit 100 can detect that an arc has occurred within that range. In this way, the control unit 100 can execute the aforementioned... Figure 2 The S206 step determines that an arc has been detected and executes the steps accordingly (e.g., the step of increasing the trip count, i.e.) Figure 2 (Step S208).

[0124] Conversely, if there are no intervals between each zero-crossing point where both the arc ignition peak and the arc extinguishing peak are above the reference value, the control unit 100 can detect that no arc has occurred. In this way, the control unit 100 can execute the aforementioned... Figure 2 The S206 step determines that no arc was detected, and executes the steps accordingly (e.g., the step of reducing the trip count, i.e.) Figure 2 (Step S210).

[0125] In the above explanation, an example was given where the high-frequency current signal used to detect whether an electric arc has occurred includes a range between multiple zero-crossing points. However, it is also possible that the high-frequency current signal includes only a range between one zero-crossing point. In this case, the control unit 100 can detect the arc ignition peak and the arc extinction peak within the range between the single zero-crossing point, and determine whether an arc has occurred within that range based on whether both the detected arc ignition peak and the arc extinction peak exceed the reference value.

[0126] On the other hand, with the aforementioned Figure 4 and Figure 5 Unlike the description in the previous embodiment, the arc detection device 10 of this invention can also determine whether an arc has occurred in the interval based on the peak value and the deviation from the position corresponding to the zero crossing point. In this case, it can prevent the signal strength of the high-frequency current signal from temporarily increasing due to noise. If the signal strength increases due to noise, even if the actual high-frequency current signal is not large, the increase in signal strength caused by the noise may lead to the mistaken belief that an arc has occurred.

[0127] Figures 6 to 7 This is used to explain how the occurrence of an electric arc is determined based on the deviation of each peak from its corresponding zero-crossing point. Figure 2 A diagram showing the action process of step S204.

[0128] first, Figure 6 This is a flowchart illustrating the process of determining whether an arc is detected in the arc detection device 10 according to the deviation of each interval divided by the zero-crossing point of the current in an embodiment of the present invention.

[0129] Reference Figure 6 The control unit 100 of the arc detection device 10 can first start from the Figure 2In step S200, the high-frequency current signal obtained is used to detect the zero-crossing point based on the voltage change of the circuit (S600). In this case, the control unit 100 can detect the time point with the reference voltage, i.e. the time point corresponding to the zero-crossing point, based on the voltage change detected during the time period corresponding to the high-frequency current signal and the phase alternation of the voltage.

[0130] In this way, the control unit 100 can divide each interval between the zero-crossings detected in step S600 into a first interval and a second interval (S602). In this case, the first interval and the second interval can be intervals with the same time length. That is, the first interval and the second interval can be intervals with a time length corresponding to half the time between each zero-crossing. Here, the first interval can be an interval that is earlier in time than the second interval.

[0131] In step S602, if the interval between each zero-crossing point is divided into a first interval and a second interval, then for the high-frequency current signal intensity value of each first interval, the control unit 100 can detect the peak with the largest deviation from the previous value. Furthermore, the detected peak can be identified as an arc ignition peak, and the deviation between the signal intensity value identified as the arc ignition peak and its previous signal intensity value is detected as a first deviation (S604).

[0132] Furthermore, for each second interval's high-frequency current signal strength value, the control unit 100 can detect the signal strength value with the largest deviation from subsequent values. The detected signal strength value can be identified as the arc extinction peak, and the deviation between the identified arc extinction peak signal strength value and subsequent signal strength values ​​can be detected as a second deviation (S606).

[0133] Figure 7 This is a diagram illustrating an example of determining the peak of the arc ignition stage (hereinafter referred to as the arc ignition peak) based on the deviation from the previous value, and determining the peak of the arc extinction stage (preferably referred to as the arc extinction peak) based on the deviation from the subsequent value.

[0134] Figure 7 and Figure 5 Similarly, curve 570, representing the change in signal strength value of the high-frequency current signal, and curve 560, representing the voltage change detected from the circuit, are shown, illustrating an example of obtaining a high-frequency current signal consisting of four intervals between five ZCPs. On the other hand, Figure 7 The amplification section 140 uses an inverting amplifier, and the greater the strength of the high-frequency current signal, the smaller the value can be.

[0135] Reference Figure 7First, the control unit 100 can divide the interval between each zero-crossing point into a first interval 701 and a second interval 702. Furthermore, it can detect the signal strength value with the largest deviation from the previous value or the largest deviation from the subsequent value from each of the divided regions, and determine the detected value as the arc ignition peak or the arc extinguishing peak.

[0136] For example, in the interval between the first zero-crossing point 711 and the second zero-crossing point 712, the control unit 100 can first detect the signal strength value with the largest deviation from the previous value in the first interval 701. In this case, if the deviation from the first zero-crossing point 711 to the first peak 721 is the largest, the control unit 100 can determine the first peak 721 as the arc ignition peak between the first zero-crossing point 711 and the second zero-crossing point 712. Furthermore, the deviation 751 between the signal strength value (first zero-crossing point) 711 before the arc ignition peak 721 and the value of the arc ignition peak 721 can be determined as the first deviation.

[0137] Furthermore, the control unit 100 can detect the signal strength value with the largest deviation from subsequent values ​​from the second interval 702. In this case, if the peak with the signal strength value having the largest deviation from subsequent values ​​is the second peak 731, the control unit 100 can determine the second peak 731 as the arc extinction peak. Furthermore, the deviation 752 between the arc extinction peak 731 and the signal strength value following the arc extinction peak 731 can be determined as the second deviation.

[0138] Furthermore, the control unit 100 can detect the signal strength value with the largest deviation from the previous value in the first interval of each interval between each zero crossing point in a similar manner, and detect the signal strength value with the largest deviation from the subsequent value in the second interval, and determine the peaks corresponding to each detected signal strength value as the arc ignition peak and the arc extinguishing peak, respectively.

[0139] Therefore, in the above Figure 7 In the first interval between each zero-crossing point, the peaks 721, 722, 723, and 724 with the largest deviation from the previous value (first deviation) can be identified as arc ignition peaks, and the peaks 731, 732, 733, and 734 with the largest deviation from the subsequent value (second deviation) in the second interval between each zero-crossing point can be identified as arc extinguishing peaks.

[0140] On the other hand, if an arc ignition peak and an arc extinction peak are determined for each interval between the zero-crossing point and the zero-crossing point, the control unit 100 can divide the interval between the zero-crossing point and the zero-crossing point into intervals corresponding to each stage of arc generation and extinction based on the determined peaks.

[0141] As an example, the control unit 100 can consider the interval from the zero-crossing point to the arc ignition peak as the interval from the arc-free stage to the arc ignition stage. Alternatively, the interval from the arc ignition peak to the arc extinguishing peak can be considered as the interval corresponding to the arc conduction stage. Furthermore, the interval from the arc extinguishing peak to the next zero-crossing point can also be considered as the interval from the arc extinguishing stage to the arc-free stage.

[0142] On the other hand, if the arc ignition peak, arc extinguishing peak, and first and second deviations are determined from the first and second intervals between each zero-crossing point in step S606, the control unit 100 can determine whether an arc has occurred based on the determined first and second deviations. In this case, the control unit 100 can detect the arc by comparing each first and second deviation with a preset reference value. Figure 2 In step S200, within the intervals between the zero-crossing points of the high-frequency current signal obtained, is there an interval where both the first deviation and the second deviation are above a preset reference value?

[0143] Furthermore, if both the first deviation and the second deviation are above the reference value, the control unit 100 can detect that an electric arc has occurred. In this way, the control unit 100 can execute the aforementioned... Figure 2 The S206 step determines that an arc has been detected and executes the steps accordingly (e.g., the step of increasing the trip count, i.e.) Figure 2 (Step S208).

[0144] Conversely, in the Figure 2 If, in the interval between each zero point of the high-frequency current signal obtained in step S200, there is no interval where both the arc ignition peak and the arc extinguishing peak are above the reference value, the control unit 100 can detect that no arc has occurred in the interval between the zero points. In this way, the control unit 100 can execute the... Figure 2 The S206 step determines that no arc was detected and executes the steps accordingly (e.g., the step of reducing the trip count, i.e.) Figure 2 (Step S210).

[0145] On the other hand, according to the above description, the arc detection device 10 of the present invention can increase or decrease the trip count according to whether an arc is detected in the interval between zero crossings, and output a trip control signal for controlling the blocking part 30 when the increased or decreased trip count exceeds a preset value, thereby ensuring the reliability of driving the blocking part 30.

[0146] Here, the control unit 100 may only be mentioned in the Figure 2If the arc detection result in step S204 meets the preset conditions, the trip count calculated so far will be reduced. Thus, if the stable state without arcing continues, the trip count can be gradually reduced.

[0147] Figure 8 This is a flowchart showing in more detail the process by which the arc detection device 10 of this embodiment of the invention reduces the trip count when the arc detection result meets the preset conditions.

[0148] Reference Figure 8 If the Figure 2 If the judgment result of step S206 is that no electric arc has occurred, then the control unit 100 can check the instrument used to detect whether an electric arc has occurred. Figure 2 Are all the measured values ​​in step S204 less than the preset reference value (S800)?

[0149] Here, the measured value can be as described. Figures 4 to 5 As explained, when determining whether an arc has occurred based on peak values, the values ​​of the arc ignition peak and the arc extinguishing peak are detected in the interval between the zero-crossing point and the zero-crossing point. If, in this case, both the values ​​of the arc ignition peak and the arc extinguishing peak are above the first reference value, it is determined that an arc has occurred in the interval between the zero-crossing points. Therefore, for the purposes described... Figure 2 The judgment result of step S206 is that no electric arc occurred, and the arc ignition peak and arc extinguishing peak between each zero crossing point can both be less than the reference value or only one of them can be greater than the first reference value. Here, the first reference value can refer to the reference value applicable when the measured value is the peak value.

[0150] Additionally, as described Figures 6 to 7 As explained, when determining whether an electric arc has occurred based on deviation, the measured values ​​can be a first deviation and a second deviation detected in the interval between the zero-crossing point and the zero-crossing point. In this case, if both the first deviation and the second deviation are above the second reference value, it is determined that an electric arc has occurred in the interval between the zero-crossing points. Therefore, for the purpose of... Figure 2 The judgment result of step S206 is that no electric arc occurred, and the first deviation and the second deviation between each zero crossing point can both be less than the second reference value, or only one deviation can be greater than the reference value. Here, the second reference value can refer to the reference value applicable when the measured value is a deviation value.

[0151] If the check result of step S800 is that neither the value of the arc ignition peak nor the value of the arc extinguishing peak are both less than the first reference value, or neither the first deviation value nor the second deviation value are both less than the second reference value, that is, if one of the values ​​of the arc ignition peak and the arc extinguishing peak is greater than the first reference value or one of the deviation values ​​of the first deviation value and the second deviation value is greater than the second reference value, then the control unit 100 can directly execute the procedure. Figure 2 The S200 step does not increment or decrement the trip count. Therefore, the control unit 100 can maintain the current trip count value and determine again whether an arc has occurred, and increment or decrement the trip count value based on whether an arc has occurred.

[0152] Conversely, if both the arc ignition peak and the arc extinguishing peak are less than the first reference value, or if both the first deviation value and the second deviation value are less than the second reference value, the control unit 100 can increase a mitigation control coefficient (S802) which serves as a reference for reducing the trip count value. Furthermore, it can check whether the increased mitigation control coefficient is above a preset threshold value (S804). If the increased mitigation control coefficient is less than the threshold value, the control unit 100 can directly execute... Figure 2 The S200 step is performed without incrementing or decrementing the trip count. Therefore, the control unit 100 can determine whether an arc has occurred again while maintaining the current trip count value.

[0153] Conversely, if the check result of step S804 indicates that the increased mitigation control coefficient reaches the critical value, the control unit 100 can determine that the trip count reduction condition is met, and decrement the trip count calculated so far by 1 (S806). Furthermore, this can be achieved by executing... Figure 2 Step S200 obtains a high-frequency current signal from at least one collected high-frequency current signal sample, and then performs the step of determining whether an arc has occurred from the obtained high-frequency current signal again. Figure 2 The operation process. Furthermore, the trip count can be increased based on whether an electric arc occurs, or the trip count can be decreased again by determining whether the decrease condition is met.

[0154] Alternatively, the mitigation control coefficient can be increased as the arc-free period lengthens. In this case, the mitigation control coefficient can be increased each time the arc-free period reaches a predetermined time, as determined by the control unit 100 (in this case, if the mitigation control coefficient increases, the arc-free period can be initialized), and the trip control count can be decreased when the mitigation control coefficient reaches a critical value.

[0155] On the other hand, according to the above description, the arc detection device 10 of this embodiment of the invention may be equipped with an ammeter. This ammeter can not only detect high-frequency current signals from the circuit between the power line and the internal circuit connected to the load, but also measure the amount of current flowing through the circuit. In this case, the control unit 900 can detect zero-crossing points based on voltage changes in the circuit, and divide the intervals between each zero-crossing point into intervals corresponding to the various stages of arc occurrence and extinction based on the high-frequency current signal. Furthermore, it can determine whether an arc has occurred in the intervals between each zero-crossing point based on the current changes detected in each of the divided intervals.

[0156] Figure 9 This is a block diagram illustrating the configuration of an arc detection device 20 according to another embodiment of the present invention, which is also equipped with an ammeter and detects the occurrence of an arc based on the current change sensed by the ammeter. Here, to distinguish it from the aforementioned arc detection device, it can be described as follows... Figure 1 The arc detection device described above, which determines whether an arc has occurred based on a high-frequency current signal detected by HFCT110 according to the zero-crossing point of voltage change, is referred to as the arc detection device 10 of the first embodiment of the present invention. The arc detection device that determines whether an arc has occurred by considering the current change of the ammeter in addition to the high-frequency current signal detected by HFCT110 according to the zero-crossing point, is referred to as the arc detection device 20 of the second embodiment of the present invention.

[0157] Reference Figure 9 The arc detection device 20 of the second embodiment of the present invention may include, in the same manner as the arc detection device 10 of the first embodiment of the present invention, an HFCT 110, a signal strength sensing unit 130 disposed between the HFCT 110 and the control unit 900 and sensing the intensity of the high-frequency current signal, and an amplification unit 140 amplifying the intensity of the sensed high-frequency current signal.

[0158] Furthermore, the arc detection device 20 of the second embodiment of the present invention, as an ammeter for detecting current, may also have an LFCT (Low Frequency Current Transformer).

[0159] Reference Figure 9 The arc detection device 20 of the second embodiment of the present invention may further be equipped with a low-frequency current signal LFCT910 for measuring the current flowing in the circuit between the power line and the internal circuit connected to the load. In this case, since the current flowing in the circuit has a low frequency, the current signal measurement result of the LFCT910 can be the result of measuring the amount of current flowing in the circuit.

[0160] On the other hand, an LPF (Low Pass Filter) 920 for removing noise from the measurement results of the LFCT 910 can be provided between the LFCT 910 and the control unit 900. Furthermore, an amplification unit 930 can be provided to amplify the measurement values ​​of the LFCT 910 to a level recognizable by the control unit 900.

[0161] Here, the current measured by the LFCT910 can be measured using the voltage detected by a pre-set shunt resistor. The shunt resistor, having a known value, can be an additional resistor. Alternatively, a part of the components constituting the arc detection device 10 can also be used as the shunt resistor.

[0162] For example, the arc detection device 10 can use a component made of bimetallic material as a switch, etc. In this case, the LFCT900 can use the component made of bimetallic material as a shunt resistor and detect the amount of current flowing between the power line and the internal circuit based on the inherent resistance value of the component made of bimetallic material. In this case, no additional shunt resistor is required.

[0163] On the other hand, the control unit 900 of the arc detection device 20 of the second embodiment of the present invention can be as described above. Figure 4 and Figure 6 As explained, the arc ignition peak and arc extinction peak are determined by measuring the high-frequency current signal intensity values ​​detected between the zero-crossing point and the zero-crossing point, based on the zero-crossing point of the circuit voltage change. Furthermore, the interval between the zero-crossing point and the zero-crossing point can be divided into intervals based on the arc occurrence and extinction cycle (hereinafter referred to as arc intervals) according to the determined arc ignition peak, arc extinction peak, and the zero-crossing point.

[0164] As an example, the arc interval can be divided into a first arc interval to a third arc interval. Here, the first arc interval corresponds to the interval from the arc-free stage to the arc ignition stage, specifically the interval from the stage where the voltage difference between the two arc contacts is small, thus preventing arc generation (arc-free stage), to the stage where the arc increases as the voltage difference gradually increases (arc ignition stage). Furthermore, the second arc interval is the interval from the arc ignition stage to the arc extinction stage, which may correspond to the stage where the arc discharges due to the voltage difference between the two arc contacts rising above a predetermined level, thus establishing conduction between the two arc contacts (arc conduction stage). Additionally, the third arc interval may be the interval from the arc extinction stage, where the arc increases again as the voltage difference decreases from its maximum value, and the current flowing between the two arc contacts decreases, to the zero-crossing point where the voltage difference becomes zero (arc-free stage).

[0165] As described above, if the arc interval is divided, the control unit 900 can match the current measurement result sensed by the ammeter, i.e., LFCT910, with the divided arc intervals to detect the current change in each arc interval.

[0166] Normally, an electric arc is a discharge phenomenon; therefore, when an arc occurs, the discharge reduces the current. Furthermore, the larger the arc, the greater the current reduction. Thus, the arc-free stage can be a state where no arc occurs, meaning no current is consumed due to the arc, and therefore it can be a state where the current flows at its maximum while the current value changes minimally. Conversely, the arc ignition and arc extinction stages are the most intense stages of arc formation, and can be states where the current consumption caused by the arc is the greatest. Additionally, the arc conduction stage is a state where the arc creates current between the two arc contacts; it can be a state where, although an arc occurs, the current conduction may reduce the arc's intensity. Therefore, it can be a state where, although the current is reduced compared to the normal current, the degree of current reduction is less than that of the arc ignition and arc extinction stages.

[0167] Therefore, the first arc interval from the arc-free stage to the arc ignition stage and the third arc interval from the arc extinguishing stage to the arc-free stage can be the intervals with the greatest change in current (e.g., 5% or more). On the other hand, the second arc interval, which is the arc conduction stage, can be the interval with a smaller decrease in current compared to the first or second arc interval.

[0168] That is, if an electric arc occurs, it exhibits the following cycle: the current changes (e.g., decreases) by a predetermined level (e.g., 5%) or more, then slightly increases, and then changes (e.g., decreases) again by a predetermined level (e.g., 5%) or more. Therefore, the control unit 900 can periodically detect the current change pattern described above within the interval between zero-crossing points and determine whether an electric arc has occurred based on the current change pattern. Alternatively, the control unit 900 can also periodically sense a current change of a predetermined level (e.g., 5%) or more within the interval between zero-crossing points and determine whether an electric arc has occurred based on the amount of current change.

[0169] on the other hand, Figure 10 It is shown that Figure 9 The control unit 900 of the arc detection device 20 of the second embodiment of the present invention described herein is a flowchart of the operation process of determining whether an arc has occurred based on the current changes in each interval corresponding to each stage of the arc's occurrence and extinction.

[0170] Reference Figure 10The control unit 900 of the arc detection device 20 of the second embodiment of the present invention can be connected with the... Figure 2 Similarly, as described above, the signal detected by the signal strength sensing unit 130 is obtained from the HFCT110, namely, a high-frequency current signal sample. Furthermore, the control unit 900 can obtain a high-frequency current signal for determining whether an arc has been detected from the collected high-frequency current signal sample (S1000).

[0171] In this way, the control unit 900 can first determine whether the obtained high-frequency current signal is a suspicious state where arcing is suspected or a normal state where arcing is not suspected (S1002). For example, the control unit 900 can detect whether there is a signal strength exceeding a preset threshold value from the obtained high-frequency current signal, and if the number of signal strengths exceeding the threshold value is less than the preset number, it can be determined as a normal state where arcing is not suspected. However, if the number of signal strengths exceeding the threshold value is greater than or equal to the preset number, it can be determined as a suspicious state where arcing is suspected.

[0172] Alternatively, if the change in current detected in the circuit between the power line and the internal circuitry in step S1002 is above a preset level (e.g., 5% of the normal current), the control unit 900 can determine that it is a suspicious state where an arc is suspected. However, if the change in current detected in the circuit between the power line and the internal circuitry is less than 5%, the control unit 900 can determine that it is a normal state where an arc is not suspected.

[0173] Alternatively, in addition to the change in current, the control unit 900 can also determine whether the condition is normal based on the periodicity of the current change. In this case, the control unit 900 can determine whether the change in current occurs periodically according to the characteristics of the zero-crossing point of alternating current. That is, if the change in current has a periodic characteristic of being minimum near the zero-crossing point and having a maximum value between the zero-crossing point and the zero-crossing point, the control unit 900 can determine that it is a suspicious condition where an arc is suspected. Conversely, if the change in current does not have a periodic characteristic, the control unit 900 can also determine that it is a normal condition where an arc is not suspected.

[0174] Here, the control unit 900 may also determine whether a state is normal in step S1002 based on a combination of two or more of the methods for determining whether a state is normal. For example, the control unit 900 may determine a state as normal only if the change in current is less than a preset level (e.g., 5%) and the change in current does not exhibit periodic characteristics. However, if the change in current is 5% or more, or even if the change in current is less than 5% but the current changes periodically (based on the zero-crossing point), it may be determined as a suspicious state where arcing is suspected. Conversely, if the change in current is less than 5% and the change in current does not exhibit periodic characteristics based on the zero-crossing point, it may be determined as a normal state where arcing is not suspected.

[0175] If the judgment result of step S1002 is that it is a normal state where there is no suspicion of arcing, then the control unit 900 can execute step S1000 again and obtain a high-frequency current signal from the collected high-frequency current signal samples. However, if the judgment result of step S1002 is that it is not a normal state, i.e., a situation where arcing is suspected, then the control unit 900 can divide the interval between the zero crossings into various arc intervals based on the peak or deviation of the high-frequency current signal detected between each zero crossing (S1004).

[0176] For example, as described Figure 4 As explained, the control unit 900 can detect a predetermined number of peaks between the first and second zero-crossing points, in descending order of the detected high-frequency current signal intensity. Furthermore, peaks near the first zero-crossing point can be identified as arc ignition peaks, while peaks near the second zero-crossing point can be identified as arc extinguishing peaks. Additionally, the interval from the first zero-crossing point to the arc ignition peak can be divided into a first arc interval, the interval between the arc ignition peak and the arc extinguishing peak can be divided into a second arc interval, and the interval from the arc extinguishing peak to the second zero-crossing point can be divided into a third arc interval.

[0177] Or, as described Figure 6 As explained, the control unit 900 can divide the interval between the first zero-crossing point and the second zero-crossing point into a first interval and a second interval. Furthermore, the peak with the largest deviation from the previous value in the first interval can be identified as the arc ignition peak, and the peak with the largest deviation from the subsequent value in the second interval can be identified as the arc extinguishing peak.

[0178] Furthermore, the interval from the first zero-crossing point to the arc ignition peak can be divided into a first arc interval, the interval between the arc ignition peak and the arc extinguishing peak can be divided into a second arc interval, and the interval from the arc extinguishing peak to the second zero-crossing point can be divided into a third arc interval.

[0179] In S1004, if the interval between the first zero-crossing point and the second zero-crossing point is divided into the first arc interval to the third arc interval, the control unit 900 can match each arc interval between the first zero-crossing point and the second zero-crossing point with the current measurement result of the LFCT910.

[0180] That is, the current change between the first zero-crossing point and the second zero-crossing point can be detected by detecting the amount of current change measured during the time period between the first zero-crossing point and the second zero-crossing point in the current measurement results of LFCT910, that is, the current change between the first arc interval and the third arc interval divided in step S1004 (S1006).

[0181] Furthermore, the control unit 900 can determine whether an arc has occurred between the first zero-crossing point and the second zero-crossing point based on the current change detection results of each arc interval in step S1006 (S1008).

[0182] For example, if there is a pattern where the current decreases significantly above a predetermined level in the first arc interval, then increases in the second arc interval, and then decreases significantly again above a predetermined level in the third arc interval, the control unit 900 can determine that an arc has occurred between the first zero-crossing point and the second zero-crossing point. Alternatively, if a current change of more than a predetermined level (e.g., 5%) is detected between the first zero-crossing point and the second zero-crossing point, the control unit 900 can determine that an arc has occurred between the first zero-crossing point and the second zero-crossing point.

[0183] On the other hand, the high-frequency current signal composed of the plurality of high-frequency current signal samples may include two or more zero-crossing points. In this case, the high-frequency current signal obtained in step S1000 may include a range between the plurality of zero-crossing points.

[0184] In this way, the control unit 900 can divide the interval between each zero-crossing point into a first arc interval to a third arc interval through step S1004. Furthermore, it can detect the current change in each arc interval, i.e., at least one of the change pattern and the amount of change, through step S1006.

[0185] Furthermore, in step S1008, the control unit 900 can detect whether at least one of the change pattern detected in step S1006 and the current change above the predetermined level has repeated more than a predetermined number of times during the interval between the plurality of zero crossings. And, if the current change pattern or the current change above the predetermined level repeats, that is, whether an arc has occurred based on whether the change pattern and the current change above the predetermined level occur periodically.

[0186] In this way, the control unit 900 can check whether an arc has occurred based on the determination result of whether an arc has occurred in step S1008 (S1010). Furthermore, if the check result of whether an arc has occurred in step S1010 is that an arc has occurred, the control unit 900 can disconnect the internal circuit and the power line by controlling the blocking unit 30.

[0187] Here, the control unit 900 can also be connected to the aforementioned Figure 2 Similarly, to ensure the reliability of the blocking unit 30, it is activated when an arc occurs more than a predetermined number of times. Therefore, if the check result in step S1010 indicates that an arc has been detected, the control unit 900 can increment the trip count of the blocking unit 30 by 1 (S1012). Conversely, if the check result in step S1010 indicates that no arc has been detected, the trip count can be decremented by 1 (S1014). In this case, the trip count can have a minimum value of 0, and the control unit 900 can maintain the current trip count even when the trip count has reached the minimum value of 0.

[0188] Here, the control unit 900 may also decrement the trip count by 1 only if a preset condition is met, based on the check result of step S1014. In this case, even if it is determined that no arc has occurred, the trip count may not be decremented if the preset condition is not met, such as the time without arc occurrence exceeding a predetermined time. In this case, the trip count may be incremented again based on the determination result of whether an arc has occurred according to the subsequently collected high-frequency current signal, without decrementing the trip count.

[0189] On the other hand, if the trip count is increased or decreased in step S1012 or S1014, the control unit 900 can check whether the increased or decreased trip count exceeds a preset value for driving the blocking unit 30 (S1016). Furthermore, if the check result of step S1016 indicates that the increased or decreased trip count does not exceed the preset value, the sampling of the high-frequency current signal can be resumed by executing step S1000 again. In this case, the operation process after step S1000 can be executed again.

[0190] However, if the check result of step S1016 is that the trip count after the increase or decrease exceeds the preset value, the control unit 900 can output a control signal to the blocking unit 30 for driving the blocking unit 30, that is, a trip control signal.

[0191] In this way, the blocking unit 30 can be driven according to the trip control signal, thereby disconnecting the power line and the internal wiring connected to the load. This cuts off the current supply, extinguishing the arc and preventing fires caused by the arc. Furthermore, the trip count can be initialized when the trip control signal is output.

[0192] On the other hand, if the check result in step S1016 shows that the trip count exceeds the preset value, the control unit 900 can output a warning signal notifying of the arc occurrence via the output unit 170 before outputting the trip control signal. Alternatively, the warning signal can be transmitted to a server or a preset device via the communication unit 180.

[0193] Furthermore, the trip control signal is output to the blocking unit 30 after a preset time or only when a trip control signal is received from the server or a preset device. This is to notify users or servers in advance of a trip caused by an electric arc, enabling them to cope with sudden power outages and thus minimizing losses caused by the power outage, such as data loss or equipment damage.

[0194] On the other hand, although the LFCT910 was used as an example of an ammeter in the above description, the LFCT910 can be replaced with a different ammeter.

[0195] Furthermore, if an inrush current occurs during the initial drive of a load connected to the internal circuitry, the detected high-frequency current signal may be higher than normal. In this case, to prevent the inrush current from being mistaken for an arc, the control unit 900 may begin detecting the occurrence of an arc after a predetermined time has elapsed since the initial drive of the load. In this case, the initial start-up time information of the load can be provided from a pre-set device such as a server or a user's mobile terminal that is communicatively connected to the arc detection device.

[0196] The aforementioned invention can be implemented by computer-readable code in a medium on which a program is recorded. Computer-readable media include all kinds of recording devices storing data readable by a computer system. Examples of computer-readable media include hard disk drives (HDDs), solid-state drives (SSDs), silicon disk drives (SDDs), ROM, RAM, CD-ROMs, magnetic tapes, floppy disks, optical data storage devices, etc., and may also include implementations in the form of carrier waves (e.g., internet-based transmissions). Therefore, the detailed description described above should not be construed as limiting in all respects, but rather as exemplary. The scope of the invention should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the invention should fall within the scope of the invention.

Claims

1. An arc detection device, characterized in that, include: The high-frequency signal sensing unit detects high-frequency signals from the current flowing in the power lines; The signal strength sensing unit senses the strength of the detected high-frequency signal; The voltage detection unit detects voltage changes in the power line; as well as The control unit detects zero-crossing points at time points with reference voltages based on the phase alternation of the voltage changes. It detects the intensity changes of high-frequency signals in the interval between the detected zero-crossing points and detects a predetermined number of peaks from the intensity changes of the high-frequency signals. It compares the signal intensity values ​​of the predetermined number of peaks with a predetermined reference value to determine whether an arc occurs in the interval.

2. The arc detection device according to claim 1, characterized in that, The control unit, The number of signal intensities exceeding a preset threshold value is detected from the intensity changes of the high-frequency signals detected in the interval. Based on whether the detected number is above the preset number, the peaks of the preset number are detected to determine whether the arc has occurred. Alternatively, if the preset number of peaks is not detected, it is determined that no arc has occurred in the interval.

3. The arc detection device according to claim 1, characterized in that, It also includes an ammeter for measuring the current in the circuit; The control unit, Based on the current measurement results, and depending on whether the current change in the interval reaches or exceeds a preset ratio of the normal current, a preset number of peaks are detected to determine whether an arc has occurred, or the preset number of peaks are not detected to determine that no arc has occurred in the interval.

4. The arc detection device according to claim 1, characterized in that, The control unit, Among the pre-set number of peaks detected, two different peaks that are adjacent to the zero-crossing points that are different from each other in the interval are respectively identified as the first peak corresponding to the arc generation stage and the second peak corresponding to the arc extinction stage. And based on the result of comparing the signal strength values ​​of the first peak and the second peak with the pre-set reference values, it is determined whether an arc has occurred in the interval.

5. The arc detection device according to claim 4, characterized in that, The control unit, High-frequency signal information, including a plurality of the aforementioned intervals, is obtained based on high-frequency signal samples collected from the signal strength sensing unit. Whether or not the electric arc occurs is determined based on whether there is an interval in which both the first peak and the second peak are above the reference value, determined from each of the plurality of intervals included in the obtained high-frequency signal information.

6. An arc detection device, characterized in that, include: The high-frequency signal sensing unit detects high-frequency signals from the current flowing in the power lines; The signal strength sensing unit senses the strength of the detected high-frequency signal; The voltage detection unit detects voltage changes in the power line; as well as The control unit detects zero-crossing points at time points with reference voltages based on the phase alternation of the voltage changes, detects intensity changes of high-frequency signals in the interval between the detected zero-crossing points, detects intensity deviations of each signal from other adjacent signals in the intensity changes of the high-frequency signals, and determines whether an arc occurs in the interval based on deviations above a preset reference value among the detected deviations.

7. The arc detection device according to claim 6, characterized in that, The control unit, The system detects the first peak with the largest deviation from the previous value and the second peak with the largest deviation from the subsequent value, and determines whether an arc occurs in the interval based on the results of comparing the first deviation (the deviation of the first peak from the value before the first peak) and the second deviation (the deviation of the second peak from the value after the second peak) with the reference value.

8. The arc detection device according to claim 7, characterized in that, The control unit, The interval is divided into a first interval and a second interval, and the first peak and the first deviation are detected in the first interval, and the second peak and the second deviation are detected in the second interval.

9. The arc detection device according to claim 7, characterized in that, The control unit, High-frequency signal information, including a plurality of said intervals, is obtained based on high-frequency signal samples collected by the signal strength sensing unit. Whether or not the electric arc occurs is determined by whether there is an interval in which both the first deviation and the second deviation are above the reference value, among the plurality of first deviations and second deviations determined in each of the plurality of intervals included in the obtained high-frequency signal information.

10. The arc detection device according to claim 6, characterized in that, The control unit, From the intensity changes of the high-frequency signals detected in the interval, the number of signal intensities exceeding a preset threshold is detected, and based on whether the detected number is above the preset number, it is determined whether an arc has occurred, or the deviation is not detected, and it is determined that no arc has occurred in the interval.

11. The arc detection device according to claim 6, characterized in that, It also includes an ammeter for measuring the current in the circuit; The control unit, Based on the current measurement results, and depending on whether the current change in the interval reaches or exceeds a preset ratio of the normal current, the occurrence of an electric arc is determined based on the deviation, or the deviation is not detected, and it is determined that no electric arc occurred in the interval.

12. An arc detection device, characterized in that, include: The high-frequency signal sensing unit detects high-frequency signals from the current flowing in the power lines; The signal strength sensing unit senses the strength of the detected high-frequency signal; The voltage detection unit detects voltage changes in the power line; An ammeter is used to measure the current in the circuit. as well as The control unit detects zero-crossing points at time points with reference voltages based on the phase alternation of the voltage changes, detects intensity changes of high-frequency signals in the interval between the detected first and second zero-crossing points, determines a first peak corresponding to the arc generation stage and a second peak corresponding to the arc extinction stage from the intensity changes of the high-frequency signals, divides the interval into a plurality of arc intervals based on the first and second peaks, and determines whether an arc has occurred in the interval based on the current change pattern of each of the divided arc intervals.

13. The arc detection device according to claim 12, characterized in that, The control unit, From the intensity changes of the high-frequency signal detected in the interval, a predetermined number of peaks are detected, and two peaks that are different from each other and are adjacent to the zero-crossing points that are different from each other in the interval are identified as the first peak and the second peak.

14. The arc detection device according to claim 12, characterized in that, The control unit, The interval is divided into a first interval and a second interval. A first peak with the largest deviation from the previous value is detected in the first interval, and a second peak with the largest deviation from the subsequent value is detected in the second interval.

15. The arc detection device according to claim 14, characterized in that, The control unit, The arc interval from the first zero-crossing point to the first peak is defined as the first arc interval from the arc-free stage to the arc ignition stage; the arc interval from the first peak to the second peak is defined as the second arc interval corresponding to the arc conduction stage; and the arc interval from the second peak to the second zero-crossing point is defined as the third arc interval from the arc extinction stage to the arc-free stage.

16. The arc detection device according to claim 15, characterized in that, When the current reduction in the first arc interval and the third arc interval is at or above a preset ratio that meets or exceeds the normal current, and the current reduction in the second arc interval is less than the current reduction in the first arc interval and the third arc interval, the control unit determines that an arc has occurred in the interval.

17. The arc detection device according to claim 12, characterized in that, The ammeter is a low-frequency current transformer sensor.

18. The arc detection device according to any one of claims 1, 6, and 12, characterized in that, The high-frequency signal sensing unit is a high-frequency current transformer sensor.

19. The arc detection device according to any one of claims 1, 6, and 12, characterized in that, It also includes a blocking part for disconnecting the power line and the internal wiring connected to the load. The control unit, The trip count is increased or decreased based on whether the electric arc occurs, and when the increased or decreased trip count reaches a preset value, a trip control signal for driving the blocking part is output to the blocking part.

20. The arc detection device according to claim 19, characterized in that, If the result of the arc occurrence determination is that no arc has occurred, the control unit reduces the trip count based on whether a preset condition is met.

21. The arc detection device according to claim 20, characterized in that, The pre-set conditions are met if no electric arc occurs within a specified time.

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