Novel low-voltage distribution line fault detector and data analysis algorithm

Abstract

The invention relates to the technical field of line fault detection, in particular to a novel low-voltage distribution line fault detector and a data analysis algorithm, and the novel low-voltage distribution line fault detector comprises a main control module which is used for overall control and waveform operation of waveform data; the waveform acquisition module is used for identifying a state waveform of line abrupt change and outputting waveform data; the transient trigger module is used for waking up the main control module when large current is generated in the line, and the detection end of the transient trigger module is connected with the corresponding line; the transient trigger module outputs a wake-up signal to the master control module to wake up the master control module to enter a high-speed operation mode when a large current is generated in a line. According to the invention, a series of work such as automatic wakeup, automatic acquisition of state waveforms and automatic judgment of the current line state of the low-voltage distribution line fault detector when the line state is suddenly changed can be realized, the automation and intelligence degree is high, the response speed is high, the wakeup speed is high, and the reliability is high.

Description

Technical Field

[0001] The present invention relates to the technical field of line fault detection, and in particular to a novel low-voltage distribution line fault detector and a data analysis algorithm. Background Art

[0002] The low-voltage distribution lines are complicated, and the maintenance workload of power repair personnel is heavy, and it is difficult to troubleshoot problems. Especially in some old communities, there are many line fault points, such as line short-circuit tripping, line over-level tripping, and switch circuit problems tripping. With the development of domestic electrical technology, a large number of switches on distribution lines have been replaced with switches made of thermal magnetic materials. When a short-circuit fault occurs in the line or a large current passes through, the thermal magnetic switch responds faster than the traditional switch, and the larger the current, the faster the response. Some switches can trigger tripping within 15ms. Traditional detection instruments have a slow response speed and cannot detect the ms-level tripping response of the thermal magnetic switch, resulting in large errors in the collected data. In the subsequent line maintenance work, the fault point cannot be accurately located, making maintenance difficult and inefficient. In addition, the existing detection instruments have high energy consumption and high maintenance costs during use. Summary of the invention

[0003] The technical problem to be solved by the present invention is that the existing detection instrument has a slow response speed and cannot detect the ms-level tripping response of the thermal magnetic switch, resulting in large errors in the collected data. In addition, the existing detection instrument has high energy consumption and high maintenance costs during use.

[0004] In order to solve the above technical problems, the first aspect of the present invention adopts the following technical solution: a new low-voltage distribution line fault detector, comprising:

[0005] A main control module, used for overall control and performing waveform operations on waveform data;

[0006] A waveform acquisition module, used to identify the state waveform of the line mutation and output waveform data;

[0007] A transient trigger module, used to wake up the main control module when a large current is generated in the circuit, and the detection end of the transient trigger module is connected to the corresponding circuit;

[0008] Among them, the main control module remains in the power-saving sleep mode before a large current is generated in the line. The transient trigger module outputs a wake-up signal to the main control module to wake it up and enter the high-speed operation mode when a large current is generated in the line. The main control module performs waveform calculation to determine the current line state after collecting the state waveform of the line through the waveform acquisition module.

[0009] When the present invention is working, it can realize a series of tasks such as automatic awakening of the low-voltage distribution line fault detector when the line state suddenly changes, automatic collection of state waveforms, and automatic judgment of the current line state. It has a high degree of automation and intelligence, a fast response speed, and can quickly and accurately collect waveform data of the line. At the same time, the instantaneous trigger module can be used to awaken the main control module from the power-saving sleep mode to the high-speed operation mode in a fast tripping response. It has a fast awakening speed and high reliability, can realize the detection of fast tripping faults, and can also effectively reduce energy consumption, extend the maintenance cycle, and have a low cost of use.

[0010] Preferably, it also includes an operational amplifier filter circuit for flipping the state waveform to a positive half-wave to reduce power consumption and for filtering, and the waveform acquisition module is connected to the circuit via the operational amplifier filter circuit.

[0011] Preferably, the transient trigger module includes a mutual inductor CT, a transistor D1, a resistor R1, a resistor R2 and a resistor R3. The first end and the second end of the mutual inductor CT are both connected to the line, the third end of the mutual inductor CT is grounded, the fourth end of the mutual inductor CT is connected to the base of the transistor D1 through the resistor R2 and is grounded through the resistor R1, the collector of the transistor D1 is connected to the wake-up end of the main control module and is connected to the power supply through the resistor R3, the emitter of the transistor D1 is grounded, and when the mutual inductor DT generates an instantaneous large current in the line, the overload current of the secondary coil is generated to drive the transistor D1 to turn on to pull down the wake-up pin of the main control module, and the main control module enters the high-speed operation mode after the wake-up pin is pulled low.

[0012] When the present invention is working, the transistor PN junction conduction threshold voltage and its amplification characteristics are used to wake up the main control module. The driving is sensitive and the pull-down speed is fast. The main control module can be quickly awakened to enter the high-speed operation mode, thereby reducing the power consumption of the low-voltage distribution line fault detector while ensuring the response speed.

[0013] Preferably, the main control module is provided with an RTC wake-up module for periodically waking up the main control module to realize periodic collection of waveform data, and the trigger end of the RTC wake-up module is connected to the wake-up end of the main control module to realize the main control module working in a low-power inspection mode.

[0014] Preferably, the waveform acquisition module is set to at least a 12-bit high-speed ADC, the sampling rate of the waveform acquisition module is set to no less than 6.4K / S, the acquisition time of the waveform acquisition module is set to more than 10mS, and the acquisition points of each phase of the waveform acquisition module are set to at least 64.

[0015] Preferably, it also includes a human-computer interaction module for displaying fault warning information and status indication to achieve human-computer interaction, and the human-computer interaction module is data-connected with the main control module to display the current line status.

[0016] In order to solve the above technical problems, the second aspect of the present invention adopts the following technical solution: a data analysis algorithm, using a novel low-voltage distribution line fault detector as described above, comprises the following steps:

[0017] S1: Collect the state waveform in the circuit and obtain waveform data;

[0018] S2: After preprocessing the waveform data, perform waveform operations;

[0019] S3: Get the maximum peak value U of the waveform in this state obtained by waveform calculation f , effective value U rms and the maximum slope K, and determine the current line status through the preset fault determination basis.

[0020] When the present invention is working, it can realize a series of tasks such as automatic collection of status waveforms and automatic judgment of the current line status. At the same time, various parameters for judging the current line status are calculated by preprocessing the waveform data and then performing waveform operations, which can effectively improve the efficiency and accuracy of the judgment.

[0021] Preferably, in step S2, when the waveform data is preprocessed, the following steps are adopted: traversing the waveform data, and removing waveform glitches in the waveform data whose duration is lower than a preset threshold.

[0022] Preferably, in step S2, when the waveform data is preprocessed, the following steps are adopted: traversing the waveform data, and removing waveform glitches in the waveform data whose duration is lower than a preset threshold.

[0023] Preferably, in step S3, the maximum peak value U of the state waveform f The operation uses the following steps:

[0024] A1: Get at least two sampling arrays in the state waveform, and use the following formula to calculate the maximum value U of each sampling array fn :

[0025] U fn =(U n-1 +U n +U n+1 ) / 3;

[0026] Where: n is the sampling array number;

[0027] A2: Compare the maximum values ​​U of several groups of sampled data fn , the maximum value of the comparison is determined as the maximum peak value U f ;

[0028] In step S3, the effective value U of the state waveform rms The calculation uses the following formula:

[0029]

[0030] Where: i is the number of sampling points;

[0031] In step S3, the maximum slope K of the state waveform is calculated using the following formula:

[0032] K=ΔU / Δt=(U fn -U0) / (t n -t0);

[0033] Where: t n is the triggering time point of large current in the line, and t0 is the time point of waveform peak occurrence;

[0034] In step S3, a rated slope K is also included. e The rated slope K is calculated using the following formula e :

[0035] K e =U fe / (t j -t0);

[0036] Among them: U fe is the maximum peak value collected under the rated current of the switch, and j is the collection time point when the maximum peak value is collected under the rated current of the switch.

[0037] Preferably, in step S3, when determining the current line state by using the preset fault determination basis, the following steps are adopted: by comparing the maximum slope K and the rated slope K of the current state waveform e , maximum peak value U f and U fe , when the maximum slope K is greater than the rated slope K e , and the maximum peak value U f Greater than U fe When the maximum slope K is less than or equal to the rated slope K, the current line state is determined to be a short circuit trip fault. e , and the maximum peak value U f Greater than U fe When the maximum slope K is less than or equal to the rated slope K, the current line state is determined to be overload tripping. e , and the maximum peak value U f Less than or equal to U fe , it is determined that the current line status is switch fault tripping.

[0038] The beneficial technical effects of the present invention include:

[0039] 1. The present invention can realize a series of tasks such as automatic awakening of the low-voltage distribution line fault detector when the line state suddenly changes, automatic collection of state waveforms, and automatic judgment of the current line state. It has a high degree of automation and intelligence, a fast response speed, and can quickly and accurately collect waveform data of the line. At the same time, the instantaneous trigger module can be used to wake up the main control module from the power-saving sleep mode to the high-speed operation mode in a fast trip response. It has a fast awakening speed and high reliability, can realize the detection of fast tripping faults, and can also effectively reduce energy consumption, extend the maintenance cycle, and have a low cost of use.

[0040] 2. The present invention uses the transistor PN junction conduction threshold voltage and its amplification characteristics to wake up the main control module. It has sensitive driving and fast pull-down speed, and can quickly wake up the main control module to enter the high-speed operation mode, thereby reducing the power consumption of the low-voltage distribution line fault detector while ensuring the response speed.

[0041] 3. The present invention can realize a series of tasks such as automatic acquisition of status waveforms and automatic judgment of the current line status. At the same time, by pre-processing the waveform data and then performing waveform operations to calculate various parameters used to judge the current line status, it can effectively improve the efficiency and accuracy of the judgment.

[0042] Other features and advantages of the present invention will be disclosed in detail in the following specific embodiments and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The present invention will be further described below in conjunction with the accompanying drawings:

[0044] Attached Figure 1 It is a structural schematic diagram of a new type of low-voltage distribution line fault detection instrument;

[0045] Attached Figure 2 This is a schematic diagram of the installation of a new type of low-voltage distribution line fault detection instrument;

[0046] Attached Figure 3 This is the circuit structure diagram of the transient trigger module;

[0047] Attached Figure 4 It is the conduction characteristic diagram of NPN transistor;

[0048] Attached Figure 5 This is the circuit structure diagram of the op amp filter circuit. DETAILED DESCRIPTION

[0049] The technical solutions of the embodiments of the present invention are explained and described below in conjunction with the drawings of the embodiments of the present invention, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work are all within the protection scope of the present invention.

[0050] In the following description, terms such as "inside", "outside", "up", "down", "left", "right", etc. that indicate directions or positional relationships are only used to facilitate the description of the embodiments and simplify the description, and do not indicate or imply that the referred device or element must have a specific direction, be constructed and operate in a specific direction. Therefore, it should not be understood as a limitation of the present invention.

[0051] Embodiment 1:

[0052] Please see attached Figure 1 , this embodiment discloses a novel low-voltage distribution line fault detector and data analysis algorithm, including:

[0053] Main control module 1, used for overall control and performing waveform operations on waveform data;

[0054] Waveform acquisition module 2, used to identify the state waveform of the line sudden change and output waveform data;

[0055] The transient trigger module 3 is used to wake up the main control module 1 when a large current is generated in the line, and the detection end of the transient trigger module 3 is connected to the corresponding line;

[0056] Among them, the main control module 1 remains in the power-saving sleep mode before a large current is generated in the line. When a large current is generated in the line, the transient trigger module 3 outputs a wake-up signal to the main control module 1 to wake it up and enter the high-speed operation mode. After the main control module 1 collects the state waveform of the line through the waveform acquisition module 2, it performs waveform calculation to determine the current line state.

[0057] When this embodiment is working, it can realize a series of tasks such as automatic awakening of the low-voltage distribution line fault detector when the line state suddenly changes, automatic collection of state waveforms, and automatic judgment of the current line state. It has a high degree of automation and intelligence, a fast response speed, and can quickly and accurately collect waveform data of the line. At the same time, the instantaneous trigger module can be used to wake up the main control module 1 from the power-saving sleep mode to the high-speed operation mode in a fast tripping response. It has a fast awakening speed and high reliability, and can realize the detection of fast tripping faults. It can also effectively reduce energy consumption, extend the maintenance cycle, and have a low cost of use.

[0058] Preferably, the waveform acquisition module 2 is set to at least a 12-bit high-speed ADC, the sampling rate of the waveform acquisition module 2 is set to no less than 6.4K / S, the acquisition time of the waveform acquisition module 2 is set to more than 10mS, and the acquisition points of each phase of the waveform acquisition module 2 are set to at least 64. It can also be implemented using a 200KHz open-type high-performance current transformer, which can identify high-frequency waveforms with sudden changes in the line, such as collecting odd harmonics, etc. The higher the frequency of the current transformer, the higher the sensitivity, which can accurately capture fault waveforms in the line.

[0059] Preferably, it also includes a human-computer interaction module 6 for displaying fault warning information and status indication to achieve human-computer interaction. The human-computer interaction module 6 is data-connected with the main control module 1 to display the current line status.

[0060] Embodiment 2:

[0061] Please see attached Figure 1 This embodiment provides a new type of low-voltage distribution line fault detector. The similarities with other embodiments are not repeated here. The differences are described in detail below with reference to the accompanying drawings.

[0062] Please see attached Figure 1 To Attachment Figure 4 In this embodiment, the transient trigger module 3 includes a mutual inductor CT, a transistor D1, a resistor R1, a resistor R2 and a resistor R3. The first end and the second end of the mutual inductor CT are both connected to the line, the third end of the mutual inductor CT is grounded, the fourth end of the mutual inductor CT is connected to the base of the transistor D1 through the resistor R2 and is grounded through the resistor R1, the collector of the transistor D1 is connected to the wake-up end of the main control module 1 and is connected to the power supply through the resistor R3, the emitter of the transistor D1 is grounded, and when the mutual inductor DT generates an instantaneous large current in the line, the overload current of the secondary coil is generated to drive the transistor D1 to turn on to pull down the wake-up pin of the main control module 1, and the main control module 1 enters the high-speed operation mode after the wake-up pin is pulled low.

[0063] When this embodiment is working, the transistor PN junction conduction threshold voltage and its amplification characteristics are used to wake up the main control module 1. The driving is sensitive and the pull-down speed is fast. The main control module 1 can be quickly awakened to enter the high-speed operation mode, thereby reducing the power consumption of the low-voltage distribution line fault detector while ensuring the response speed.

[0064] In specific implementation, the normal induction current of the transformer coil is ln=0-20mA, the instantaneous overload capacity is 2 times, and the coil driving capacity is 20 ohms. In order to achieve low power consumption design, this embodiment selects the NPN transistor D1PN junction conduction threshold voltage and its amplification characteristics. The induction coil driving voltage is Vn=ln*20Ω. When not overloaded, its voltage range is 0-0.4V, and when overloaded, the voltage range is 0.4-0.8V. This driving voltage is input to the base-emitter of the NPN transistor D1. Under normal circumstances, the base-emitter is not conductive, and it is conductive when overloaded. Please refer to the attached Figure 2 and attached Figure 3 , which is the circuit structure diagram of transient trigger module 3 and the conduction characteristic diagram of NPN transistor D1. When an overcurrent fault occurs in the line, a large current will be generated in the line instantly. The transformer will sense and generate an overload current of the secondary coil. The transformer CT drives NPN transistor D1 to conduct, pulling down the wake-up end of the main control module 1, that is, the MCU_IO pin, thereby triggering the awakening of the main control module 1 to work, which can greatly reduce the internal resource consumption of the low-voltage distribution line fault detector. The main control module 1 can be quickly started within 300uS to collect the state waveform of the line.

[0065] As a further improvement of this embodiment, the main control module 1 is provided with an RTC wake-up module 5 for periodically waking up the main control module 1 to realize periodic collection of waveform data. The trigger end of the RTC wake-up module 5 is connected to the wake-up end of the main control module 1 to realize the operation of the main control module 1 in a low-power inspection mode. The RTC is used to periodically wake up the main control module 1 to realize periodic collection of waveform data. The RTC wake-up module 5 cooperates with the transient trigger module 3 to realize periodic inspection function and instantaneous trigger function. While ensuring the real-time and accuracy of the waveform data, the energy consumption of the low-voltage distribution line fault detector is optimized, and its maintenance cycle is greatly extended, so that it can basically be maintenance-free throughout the life cycle.

[0066] Embodiment three:

[0067] Please see attached Figure 5 This embodiment provides a new type of low-voltage distribution line fault detector. The similarities with other embodiments are not repeated here. The differences are described in detail below with reference to the accompanying drawings.

[0068] In this embodiment, it also includes an operational amplifier filtering circuit 4 for flipping the state waveform to a positive half-wave to reduce power consumption and for filtering. The waveform acquisition module 2 is connected to the line through the operational amplifier filtering circuit 4. The negative half-wave in the waveform data of the line is flipped into a half-wave through the filtering operational amplifier circuit, which can reduce power consumption.

[0069] In a specific implementation, the operational amplifier filter circuit 4 includes an operational amplifier ICA, an operational amplifier ICB, a diode D1, a resistor R4, a resistor R11, a resistor R22, a resistor R33, and a capacitor C1. The in-phase input terminal of the operational amplifier ICA is connected to the first end of the resistor R22 and the inverting input terminal of the operational amplifier ICB. The inverting input terminal of the operational amplifier ICA is connected to the second end of the resistor R22 through the resistor R33. The second section of the resistor R22 is connected to the corresponding line and is grounded through the resistor R11 and the capacitor C1 respectively. The output terminal of the operational amplifier ICA is connected to the waveform acquisition module 2 and is connected to the inverting input terminal of the operational amplifier ICA through the resistor R4 and the capacitor C3 respectively. The output terminal of the operational amplifier ICB is connected to the waveform acquisition module 2 through the diode The diode D1 is connected to the inverting input terminal of the operational amplifier ICB, and the non-inverting input terminal of the operational amplifier ICB is grounded. When working, the AC current signal of the line passes through the resistor R11 to generate an AC voltage signal at both ends of R1. When the input signal is in the positive half cycle (i.e., Vin>0V), the operational amplifier ICA acts as an adder amplifier, and ICB will not affect the operation of ICA at this stage. When the input signal enters the negative half cycle (i.e., Vin<0V), the diode D1 and the operational amplifier ICB work together to form a ground clamp to ensure that the non-inverting input terminal of the operational amplifier ICA is maintained at 0V. At this time, the operational amplifier ICA is mainly used as an inverting amplifier, and finally a full-wave rectified signal is output from the output terminal of the operational amplifier ICA to the waveform acquisition module 2.

[0070] Preferably, the output end of the operational amplifier ICA may be connected to the transient trigger module 3, so as to improve the wake-up efficiency and reduce the probability of false wake-up.

[0071] Embodiment 4:

[0072] Please see attached Figure 1 This embodiment provides a data analysis algorithm, which is applied to a novel low-voltage distribution line fault detection instrument as in the above embodiment, and includes the following steps:

[0073] S1: Collect the state waveform in the circuit and obtain waveform data;

[0074] S2: After preprocessing the waveform data, perform waveform operations;

[0075] S3: Get the maximum peak value U of the waveform in this state obtained by waveform calculation f , effective value U rms and the maximum slope K, and determine the current line status through the preset fault determination basis.

[0076] When this embodiment is working, it can realize a series of tasks such as automatic collection of status waveforms and automatic judgment of the current line status. At the same time, by pre-processing the waveform data and then performing waveform operations to calculate various parameters used to judge the current line status, it can effectively improve the efficiency and accuracy of the judgment.

[0077] In this embodiment, in step S2, when the waveform data is preprocessed, the following steps are adopted: traversing the waveform data, and removing the waveform glitches in the waveform data whose duration is lower than a preset threshold.

[0078] In the specific implementation, in step S3, the maximum peak value U of the state waveform f The operation uses the following steps:

[0079] A1: Get at least two sampling arrays in the state waveform, and use the following formula to calculate the maximum value U of each sampling array fn :

[0080] U fn =(U n-1 +U n +U n+1 ) / 3;

[0081] Where: n is the sampling array number;

[0082] A2: Compare the maximum values ​​U of several groups of sampled data fn , the maximum value of the comparison is determined as the maximum peak value U f ;

[0083] In step S3, the effective value U of the state waveform rms The calculation uses the following formula:

[0084]

[0085] Where: i is the number of sampling points;

[0086] In step S3, the maximum slope K of the state waveform is calculated using the following formula:

[0087] K=ΔU / Δt=(U fn -U0) / (t n -t0);

[0088] Where: t n is the triggering time point of large current in the line, and t0 is the time point of waveform peak occurrence;

[0089] In step S3, the rated slope K is also included. e The rated slope K is calculated using the following formula e :

[0090] K e =U fe / (t j -t0);

[0091] Among them: U fe is the maximum peak value collected under the rated current of the switch, and j is the collection time point when the maximum peak value is collected under the rated current of the switch.

[0092] Preferably, in step S3, when determining the current line state by using the preset fault determination basis, the following steps are adopted: by comparing the maximum slope K of the current state waveform and the rated slope K e , maximum peak value U f and U fe , when the maximum slope K is greater than the rated slope K e , and the maximum peak value U f Greater than U fe When the maximum slope K is less than or equal to the rated slope K, the current line state is determined to be a short circuit trip fault. e , and the maximum peak value U f Greater than U fe When the maximum slope K is less than or equal to the rated slope K, the current line state is determined to be overload tripping. e , and the maximum peak value U f Less than or equal to U fe , it is determined that the current line status is switch fault tripping.

[0093] The beneficial technical effects of this embodiment include: this embodiment can realize a series of tasks such as automatic awakening of the low-voltage distribution line fault detector when the line state suddenly changes, automatic collection of state waveforms, and automatic judgment of the current line state. It has a high degree of automation and intelligence, a fast response speed, and can quickly and accurately collect line waveform data. At the same time, the instantaneous trigger module can be used to wake up the main control module from the power-saving sleep mode to the high-speed operation mode in a fast tripping response. It has a fast awakening speed and high reliability, and can realize the detection of fast tripping faults. It can also effectively reduce energy consumption, extend the maintenance cycle, and have a low cost of use.

[0094] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that the present invention includes but is not limited to the contents described in the drawings and the above specific embodiments. Any modification that does not deviate from the functional and structural principles of the present invention will be included in the scope of the claims.

Claims

1. A new type of low voltage distribution line fault detector, characterized in that: include: A main control module (1), used for overall control and performing waveform operations on waveform data; A waveform acquisition module (2) is used to identify the state waveform of the line sudden change and output the waveform data; A transient trigger module (3) is used to wake up the main control module (1) when a large current is generated in the circuit, and a detection end of the transient trigger module (3) is connected to a corresponding circuit; The main control module (1) remains in a power-saving sleep mode before a large current is generated in the line, the transient trigger module (3) outputs a wake-up signal to the main control module (1) when a large current is generated in the line to wake it up and enter a high-speed operation mode, and the main control module (1) performs waveform calculation to determine the current line state after collecting the line state waveform through the waveform collection module (2).

2. A novel low-voltage distribution line fault detector according to claim 1, characterized in that: It also includes an operational amplifier filter circuit (4) for flipping the state waveform to a positive half-wave to reduce power consumption and for filtering. The waveform acquisition module (2) is connected to the circuit via the operational amplifier filter circuit (4).

3. A novel low-voltage distribution line fault detector according to claim 1, characterized in that: The transient trigger module (3) comprises a mutual inductor CT, a transistor D1, a resistor R1, a resistor R2 and a resistor R3. The first end and the second end of the mutual inductor CT are both connected to the line, the third end of the mutual inductor CT is grounded, the fourth end of the mutual inductor CT is connected to the base of the transistor D1 through the resistor R2 and is grounded through the resistor R1, the collector of the transistor D1 is connected to the wake-up end of the main control module (1) and is connected to the power supply through the resistor R3, the emitter of the transistor D1 is grounded, and when the mutual inductor DT generates an instantaneous large current in the line, the overload current of the secondary coil is generated to drive the transistor D1 to turn on so as to pull down the wake-up pin of the main control module (1), and the main control module (1) enters a high-speed operation mode after the wake-up pin is pulled down.

4. A novel low-voltage distribution line fault detector according to claim 1, characterized in that: The main control module (1) is provided with an RTC wake-up module (5) for periodically waking up the main control module (1) to realize periodic collection of waveform data, and a trigger end of the RTC wake-up module (5) is connected to a wake-up end of the main control module (1) to realize the main control module (1) working in a low-power inspection mode.

5. The novel low-voltage distribution line fault detector according to claim 1 is characterized in that: The waveform acquisition module (2) is configured as at least a 12-bit high-speed ADC, the sampling rate of the waveform acquisition module (2) is configured to be no less than 6.4K / S, the acquisition time of the waveform acquisition module (2) is configured to be more than 10ms, and the number of acquisition points for each phase of the waveform acquisition module (2) is configured to be at least 64.

6. A novel low-voltage distribution line fault detector according to claim 1, characterized in that: It also includes a human-machine interaction module (6) for displaying fault warning information and status indication to achieve human-machine interaction, and the human-machine interaction module (6) is data-connected to the main control module (1) to display the current line status.

7. A data analysis algorithm, applied to a novel low-voltage distribution line fault detector according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1: Collect the state waveform in the circuit and obtain waveform data; S2: After preprocessing the waveform data, perform waveform operations; S3: Get the maximum peak value U of the waveform in this state obtained by waveform calculation f , effective value U rms and the maximum slope K, and determine the current line status through the preset fault determination basis.

8. A data analysis algorithm according to claim 7, characterized in that: In step S2, when the waveform data is preprocessed, the following steps are adopted: traversing the waveform data, and removing the waveform glitches in the waveform data whose duration is lower than a preset threshold.

9. A data analysis algorithm according to claim 7, characterized in that: In step S3, the maximum peak value U of the state waveform f The operation uses the following steps: A1: Get at least two sampling arrays in the state waveform, and use the following formula to calculate the maximum value U of each sampling array fn : IN fn =(U n-1 +U n +U n+1 ) / 3; Where: n is the sampling array number; A2: Compare the maximum values ​​U of several groups of sampled data fn , the maximum value of the comparison is determined as the maximum peak value U f ; In step S3, the effective value U of the state waveform rms The calculation uses the following formula: Where: i is the number of sampling points; In step S3, the maximum slope K of the state waveform is calculated using the following formula: K=ΔU / Δt=(U fn -U0) / (t n -t0); Where: t n is the triggering time point of large current in the line, and t0 is the time point of waveform peak occurrence; In step S3, a rated slope K is also included. e The rated slope K is calculated using the following formula e : K e =U fe / (t j -t0); Among them: U fe is the maximum peak value collected under the rated current of the switch, and j is the collection time point when the maximum peak value is collected under the rated current of the switch.

10. A data analysis algorithm according to claim 9, characterized in that: In step S3, when the current line state is determined by the preset fault determination basis, the following steps are adopted: by comparing the maximum slope K of the current state waveform and the rated slope K e , maximum peak value U f and U fe , when the maximum slope K is greater than the rated slope K e , and the maximum peak value U f Greater than U fe When the maximum slope K is less than or equal to the rated slope K, the current line state is determined to be a short circuit trip fault. e , and the maximum peak value U f Greater than U fe When the maximum slope K is less than or equal to the rated slope K, the current line state is determined to be overload tripping. e , and the maximum peak value U f Less than or equal to U fe , it is determined that the current line status is switch fault tripping.

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