Method and system for determining a hidden hazard of a power distribution line arc fault

Abstract

The application discloses a kind of distribution line fault arc hidden danger determination methods, including the data information of real-time acquisition target distribution line;The change of each data is calculated;Primary determination of target distribution line fault arc hidden danger is carried out;The dimensional determination value of the change of each data is calculated;Secondary determination of target distribution line fault arc hidden danger is carried out;Complete target distribution line fault arc hidden danger determination.The application also discloses a kind of system for realizing the distribution line fault arc hidden danger determination method.The application obtains the multidimensional real-time data information of target line, combines two angles of time domain and frequency domain, through primary determination and secondary determination, not only realizes the fault arc hidden danger determination of distribution line, but also has higher reliability, better accuracy, and the scheme is simple and convenient.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of electrical automation, and particularly relates to a method and system for judging hidden faults of arc in a power distribution line. BACKGROUND

[0002] With the development of economy and technology and the improvement of people's living standards, electric energy has become an essential secondary energy in people's production and life, bringing endless convenience to people's production and life. Therefore, ensuring the stable and reliable supply of electric energy has become one of the most important tasks of the power system.

[0003] Electrical fire is one of the most serious faults of the power system, which can cause great harm to the power system. One of the main causes of electrical fire is fault arc; therefore, the judgment of hidden faults of arc in the power distribution line is of great significance for preventing power line fires.

[0004] At present, the commonly used schemes for judging hidden faults of arc in the power distribution line are mainly physical sensor detection schemes and electrical quantity sensor detection schemes: the physical sensor detection method installs temperature sensors, smoke sensors, cameras and other devices at key lines or positions prone to electrical fires to collect physical information when fault arcs occur, so as to realize the identification of fault arcs; but after the fact, the monitoring range of this method is limited, and the installation and maintenance cost of the equipment is high. The electrical quantity sensor detection scheme uses voltage sensors, current sensors and other devices to collect electrical quantity data of the line, and diagnoses the line fault arc by setting corresponding threshold values; however, the existing schemes usually consider fewer dimensions, are easily affected by load changes, and have problems such as limited application scenarios, low diagnosis accuracy, high false alarm rate, etc. SUMMARY

[0005] One of the purposes of the present application is to provide a method for judging hidden faults of arc in a power distribution line, which is high in reliability, good in accuracy, simple and convenient.

[0006] The second purpose of the present application is to provide a system for realizing the method for judging hidden faults of arc in the power distribution line.

[0007] The method for judging hidden faults of arc in the power distribution line provided by the present application comprises the following steps:

[0008] S1. Real-time acquisition of data information of the target power distribution line;

[0009] S2. Calculation of the change amount of each data according to the data information acquired in step S1;

[0010] S3. Preliminary judgment of hidden faults of arc in the target power distribution line according to the change amount data obtained in step S2;

[0011] S4. Calculate the dimension determination value of the change amount of each data according to the determination result obtained in step S3 and the data information obtained in step S1;

[0012] S5. Perform secondary determination of the target power distribution line fault arc hidden danger according to the dimension determination value obtained in step S4;

[0013] S6. Complete the determination of the target power distribution line fault arc hidden danger according to the determination result obtained in step S5.

[0014] The data information of the target power distribution line obtained in real time in step S1 specifically includes the following steps:

[0015] According to the set sampling frequency, the voltage data, current data, power data, power factor data and line harmonic data of the target power distribution line are obtained.

[0016] According to the data information obtained in step S1, the change amount of each data is calculated in step S2, which specifically includes the following steps:

[0017] The current change amplitude ΔI is calculated by the following formula t12 :

[0018] ΔI t12 =I t1 -I t2

[0019] In the formula, I t1 is the current amplitude at t1; I t2 is the current amplitude at t2; t1 and t2 are adjacent time points;

[0020] The odd harmonic change amplitude ΔOH is calculated by the following formula t12 :

[0021] ΔOH t12 =|OH t1 -OH t2 |

[0022] In the formula, OH t1 is the odd harmonic total content amplitude at t1; OH t2 is the odd harmonic total content amplitude at t2;

[0023] The even harmonic change amplitude ΔEH is calculated by the following formula t12 :

[0024] ΔEH t12 =|EH t1 -EH t2 |

[0025] EH t1 is the total even harmonic content amplitude at time t1; EH t2 is the total even harmonic content amplitude at time t2.

[0026] Step S3: According to the change data obtained in step S2, a preliminary determination of the target distribution power line fault arc hidden danger is performed, specifically including the following steps:

[0027] The preliminary determination index ILFDM of the target distribution power line fault arc hidden danger is calculated by using the following formula:

[0028] ILFDM=k1ΔI t12 +k2ΔOH t12 +k3ΔEH t12

[0029] wherein k1 is the first weight coefficient; k2 is the second weight coefficient; and k3 is the third weight coefficient;

[0030] According to the obtained ILFDM, the preliminary determination of the target distribution power line fault arc hidden danger is performed by using the following rules:

[0031] If ILFDM>θ1, it is preliminarily determined that the target distribution power line has a fault arc hidden danger, and subsequent steps are performed; θ1 is a set preliminary threshold value.

[0032] If ILFDM≤θ1, it is preliminarily determined that the target distribution power line does not have a fault arc hidden danger, and the algorithm ends.

[0033] Step S4: According to the determination result obtained in step S3 and the data information obtained in step S1, the dimensional determination value of the change amount of each data is calculated, specifically including the following steps:

[0034] The current mutation amplitude |ΔI t12 | is calculated by using the following formula:

[0035] |ΔI t12 | = |I t1 -I t2 |

[0036] wherein I t1 is the current amplitude at time t1; I t2 is the current amplitude at time t2; t1 and t2 are adjacent times.

[0037] The current variance amplitude σI t123 is calculated by using the following formula:

[0038]

[0039] wherein is the line current average value at time t1, time t2 and time t3; time t2 and time t3 are adjacent time; I t3 is the current amplitude at time t3;

[0040] The power mutation amplitude ΔP is calculated by the following formula t12 :

[0041] ΔP t12 = |P t1 -P t2 |

[0042] In the formula, P t1 is the line power at time t1; P t2 is the line power at time t2;

[0043] The odd harmonic mutation amplitude |ΔOH is calculated by the following formula t12 |:

[0044] |ΔOH t12 | = |OH t1 -OH t2 |

[0045] In the formula, OH t1 is the odd harmonic total content amplitude at time t1; OH t2 is the odd harmonic total content amplitude at time t2;

[0046] The even harmonic mutation amplitude |ΔEH is calculated by the following formula t12 |:

[0047] |ΔEH t12 | = |EH t1 -EH t2 |

[0048] In the formula, EH t1 is the even harmonic total content amplitude at time t1; EH t2 is the even harmonic total content amplitude at time t2;

[0049] If |ΔI t12 | > θ2, then α = 1, if |ΔI t12 | ≤ θ2, then α = 0, θ2 is the set current change threshold, and α is the current mutation amplitude dimension;

[0050] If σI t123 > θ3, then β = 1, if σI t123 ≤ θ3, then β = 0, θ3 is the set current variance threshold, and β is the current variance amplitude dimension;

[0051] If ΔP t12 > θ4, then χ = 1, if ΔPt12 if |ΔOH| > θ4, then χ = 0, θ4 is a set power mutation threshold, χ is a power mutation amplitude dimension;

[0052] if |ΔOH| > θ4, then χ = 0, θ4 is a set power mutation threshold, χ is a power mutation amplitude dimension; t12 if |ΔOH| > θ5, then δ = 1, if |ΔOH| ≤ θ5, then δ = 0, θ5 is a set odd harmonic mutation amplitude, δ is an odd harmonic mutation amplitude dimension; t12 if |ΔOH| > θ5, then δ = 1, if |ΔOH| ≤ θ5, then δ = 0, θ5 is a set odd harmonic mutation amplitude, δ is an odd harmonic mutation amplitude dimension;

[0053] if |ΔOH| > θ4, then χ = 0, θ4 is a set power mutation threshold, χ is a power mutation amplitude dimension; t12 if |ΔOH| > θ5, then δ = 1, if |ΔOH| ≤ θ5, then δ = 0, θ5 is a set odd harmonic mutation amplitude, δ is an odd harmonic mutation amplitude dimension; t12 if |ΔOH| > θ5, then δ = 1, if |ΔOH| ≤ θ5, then δ = 0, θ5 is a set odd harmonic mutation amplitude, δ is an odd harmonic mutation amplitude dimension;

[0054] Step S5: According to the dimension judgment value obtained in step S4, a secondary judgment of the target power distribution line fault arc hidden danger is performed, and the secondary judgment specifically includes the following steps:

[0055] The secondary judgment index FLFDM of the target power distribution line fault arc hidden danger is calculated by using the following formula:

[0056] FLFDM = m1FLFDM1 + m2FLFDM2

[0057] In the formula, m1 is a time domain diagnosis weight coefficient; m2 is a frequency domain diagnosis weight coefficient; FLFDM1 is a time domain diagnosis index, and FLFDM1 = a1α + a2β + a3χ, a1 is a current change weight coefficient, a2 is a current variance weight coefficient, and a3 is a power mutation weight coefficient; FLFDM2 is a frequency domain diagnosis index, and FLFDM2 = a4δ + a5ε, a4 is an odd harmonic weight coefficient, and a5 is an even harmonic weight coefficient;

[0058] According to the obtained FLFDM, a secondary judgment of the target power distribution line fault arc hidden danger is performed:

[0059] If FLFDM ≤ TT1, it is determined that the target power distribution line does not exist a fault arc hidden danger;

[0060] If TT1 < FLFDM < TT2, the next round of judgment is continued;

[0061] If FLFDM ≥ TT2, it is determined that the target power distribution line exists a fault arc hidden danger;

[0062] If the judgment results of two consecutive rounds are both TT1 < FLFDM < TT2, it is determined that the target power distribution line exists a fault arc hidden danger.

[0063] The application further provides a system for realizing the distribution line fault arc hidden danger determination method, comprising a data acquisition module, a change calculation module, a primary determination module, a dimension calculation module, a secondary determination module and a hidden danger determination module; the data acquisition module, the change calculation module, the primary determination module, the dimension calculation module, the secondary determination module and the hidden danger determination module are sequentially connected; the data acquisition module is used for acquiring data information of a target distribution line in real time, and uploading the data information to the change calculation module; the change calculation module is used for calculating the change amount of each data according to the received data information and the acquired data information, and uploading the data information to the primary determination module; the primary determination module is used for performing primary determination of the target distribution line fault arc hidden danger according to the received data information and the obtained change amount data, and uploading the data information to the dimension calculation module; the dimension calculation module is used for calculating the dimension determination value of the change amount of each data according to the received data information, the obtained determination result and the acquired data information, and uploading the data information to the secondary determination module; the secondary determination module is used for performing secondary determination of the target distribution line fault arc hidden danger according to the received data information and the obtained dimension determination value, and uploading the data information to the hidden danger determination module; and the hidden danger determination module is used for completing the hidden danger determination of the target distribution line fault arc according to the received data information and the obtained determination result.

[0064] The distribution line fault arc hidden danger determination method and system provided by the application realize the fault arc hidden danger determination of the distribution line, have higher reliability and better accuracy, and are simple and convenient. BRIEF DESCRIPTION OF DRAWINGS

[0065] Figure 1 The figure is a method flowchart of the method of the application.

[0066] Figure 2 The figure is a function module schematic diagram of the system of the application. DETAILED DESCRIPTION

[0067] As shown in the figure, the distribution line fault arc hidden danger determination method disclosed by the application comprises the following steps: Figure 1 The figure is a method flowchart of the method of the application: the distribution line fault arc hidden danger determination method disclosed by the application comprises the following steps:

[0068] S1. Real-time acquisition of data information of a target distribution line; specifically comprising the following steps:

[0069] According to the set sampling frequency (preferably 1 sample per second), voltage data, current data, power data, power factor data and line harmonic data of the target distribution line are acquired;

[0070] S2. According to the data information obtained in step S1, the variation of each data is calculated; specifically including the following steps:

[0071] The current variation amplitude ΔI is calculated by the following formula t12 :

[0072] ΔI t12 = I t1 -I t2

[0073] In the formula, I t1 is the current amplitude at t1; I t2 is the current amplitude at t2; t1 and t2 are adjacent time points;

[0074] The odd harmonic variation amplitude ΔOH is calculated by the following formula t12 :

[0075] ΔOH t12 = |OH t1 -OH t2 |

[0076] In the formula, OH t1 is the total content amplitude of odd harmonics at t1; OH t2 is the total content amplitude of odd harmonics at t2;

[0077] The even harmonic variation amplitude ΔEH is calculated by the following formula t12 :

[0078] ΔEH t12 = |EH t1 -EH t2 |

[0079] In the formula, EH t1 is the total content amplitude of even harmonics at t1; EH t2 is the total content amplitude of even harmonics at t2;

[0080] S3. According to the variation data obtained in step S2, the preliminary determination of the target distribution power line fault arc hidden danger is performed; specifically including the following steps:

[0081] The preliminary determination index ILFDM of the target distribution power line fault arc hidden danger is calculated by the following formula

[0082] ILFDM = k1ΔI t12 +k2ΔOH t12 +k3ΔEH t12

[0083] In the formula, k1 is the first weight coefficient; k2 is the second weight coefficient; k3 is the third weight coefficient;

[0084] According to the obtained ILFDM, the following rule is adopted to preliminarily determine the fault arc hidden danger of the target distribution and utilization circuit:

[0085] If ILFDM> θ1, it is preliminarily determined that the target distribution and utilization circuit has the fault arc hidden danger, and the subsequent step is performed; θ1 is a preliminarily set threshold value;

[0086] If ILFDM≤ θ1, it is preliminarily determined that the target distribution and utilization circuit does not have the fault arc hidden danger, and the algorithm ends;

[0087] S4. According to the determination result obtained in step S3 and the data information obtained in step S1, a dimensional determination value of the change amount of each data is calculated; specifically including the following steps:

[0088] The current mutation amplitude |ΔI is calculated by using the following formula: t12

[0089] |ΔI t12 |=|I t1 -I t2 |

[0090] In the formula, I t1 is the current amplitude at t1; I t2 is the current amplitude at t2; t1 and t2 are adjacent time points;

[0091] The current variance amplitude σI is calculated by using the following formula: t123

[0092]

[0093] In the formula, I is the average value of the line current at t1, t2 and t3; t2 and t3 are adjacent time points; I t3 is the current amplitude at t3;

[0094] The power mutation amplitude ΔP is calculated by using the following formula: t12

[0095] ΔP t12 =|P t1 -P t2

[0096] In the formula, P t1 is the line power at t1; P t2 is the line power at t2;

[0097] The odd harmonic mutation amplitude |ΔOH is calculated by using the following formula: t12 ​​​​

[0098] |ΔOH t12 |=|OH t1 -OH t2 |

[0099] OH t1 is the total amplitude of odd harmonic at t1 moment; OH t2 is the total amplitude of odd harmonic at t2 moment;

[0100] The following formula is used to calculate the even harmonic mutation amplitude |ΔEH t12 |:

[0101] |ΔEH t12 |=|EH t1 -EH t2 |

[0102] EH t1 is the total amplitude of even harmonic at t1 moment; EH t2 is the total amplitude of even harmonic at t2 moment;

[0103] If |ΔI t12 |>θ2, then α=1, if |ΔI t12 |≤θ2, then α=0, θ2 is a set current change threshold, and α is a current mutation amplitude dimension;

[0104] If σI t123 >θ3, then β=1, if σI t123 ≤θ3, then β=0, θ3 is a set current variance threshold, and β is a current variance amplitude dimension;

[0105] If ΔP t12 >θ4, then χ=1, if ΔP t12 ≤θ4, then χ=0, θ4 is a set power mutation threshold, and χ is a power mutation amplitude dimension;

[0106] If |ΔOH t12 |>θ5, then δ=1, if |ΔOH t12 |≤θ5, then δ=0, θ5 is a set odd harmonic mutation amplitude, and δ is an odd harmonic mutation amplitude dimension;

[0107] If |ΔEH t12 |>θ6, then ε=1, if |ΔEH t12 |≤θ6, then ε=0, θ6 is a set even harmonic mutation amplitude, and ε is an even harmonic mutation amplitude dimension;

[0108] S5. According to the dimension judgment value obtained in step S4, a secondary judgment of the target power distribution line fault arc hidden danger is performed; specifically including the following steps:

[0109] The secondary determination index FLFDM of the target distribution line fault arc hidden danger is calculated by using the following formula:

[0110] FLFDM = m1FLFDM1 + m2FLFDM2

[0111] In the formula, m1 is a time domain diagnosis weight coefficient; m2 is a frequency domain diagnosis weight coefficient; FLFDM1 is a time domain diagnosis index, and FLFDM1 = a1α + a2β + a3χ, a1 is a current change weight coefficient, a2 is a current variance weight coefficient, and a3 is a power mutation weight coefficient; FLFDM2 is a frequency domain diagnosis index, and FLFDM2 = a4δ + a5ε, a4 is an odd harmonic weight coefficient, and a5 is an even harmonic weight coefficient;

[0112] According to the obtained FLFDM, the secondary determination of the target distribution line fault arc hidden danger is performed.

[0113] If FLFDM≤TT1, it is determined that the target distribution line does not exist fault arc hidden danger.

[0114] If TT1<FLFDM<TT2, the next round of determination is continued.

[0115] If FLFDM≥TT2, it is determined that the target distribution line exists fault arc hidden danger.

[0116] If the determination results of two consecutive rounds are both TT1<FLFDM<TT2, it is determined that the target distribution line exists fault arc hidden danger.

[0117] S6. According to the determination result obtained in step S5, the hidden danger determination of the target distribution line fault arc is completed.

[0118] As Figure 2The system of the application is shown in the functional module diagram: the system for realizing the method for judging the arc fault hidden danger of the power distribution line disclosed in the application comprises a data acquisition module, a change calculation module, a primary judgment module, a dimension calculation module, a secondary judgment module and a hidden danger judgment module; the data acquisition module, the change calculation module, the primary judgment module, the dimension calculation module, the secondary judgment module and the hidden danger judgment module are sequentially connected; the data acquisition module is used for acquiring the data information of the target power distribution line in real time, and uploading the data information to the change calculation module; the change calculation module is used for calculating the change amount of each data according to the received data information and the acquired data information, and uploading the data information to the primary judgment module; the primary judgment module is used for performing the primary judgment of the arc fault hidden danger of the target power distribution line according to the received data information and the obtained change amount data, and uploading the data information to the dimension calculation module; the dimension calculation module is used for calculating the dimension judgment value of the change amount of each data according to the received data information, the obtained judgment result and the acquired data information, and uploading the data information to the secondary judgment module; the secondary judgment module is used for performing the secondary judgment of the arc fault hidden danger of the target power distribution line according to the received data information and the obtained dimension judgment value, and uploading the data information to the hidden danger judgment module; and the hidden danger judgment module is used for completing the hidden danger judgment of the arc fault of the target power distribution line according to the received data information and the obtained judgment result.

Claims

1. A method for determining arc fault hazards in distribution power lines, comprising the following steps: S1. Real-time acquisition of target power distribution line data information; S2. Calculate the change in each data according to the data information obtained in step S1; S3. According to the variation data obtained in step S2, the target distribution power line arc fault hidden dangers are determined initially; S4. Calculate the dimension determination value of each data change amount based on the determination result obtained in step S3 and the data information obtained in step S1; specifically, the steps include: The current mutation amplitude |ΔI is calculated using the following formula: t12 |: |ΔI t12 |=|I t1 -I t2 | Where I t1 is the current amplitude at time t1; I t2 is the current amplitude at time t2; time t1 and time t2 are adjacent times; The current variance amplitude σI is calculated using the following formula: t123 : In the formula is the average value of the line current at time t1, time t2 and time t3; time t2 and time t3 are adjacent times; I t3 is the current amplitude at time t3; The power mutation amplitude ΔP is calculated using the following formula: t12 : ΔP t12 =|P t1 -P t2 | Where P t1 is the line power at time t1; P t2 is the line power at time t2; The odd harmonic mutation amplitude |ΔOH is calculated using the following formula: t12 |: |ΔOH t12 |=|OH t1 -OH t2 | Where OH t1 is the total amplitude of odd harmonics at time t1; OH t2 is the total amplitude of odd harmonics at time t2; The even harmonic mutation amplitude |ΔEH is calculated using the following formula: t12 |: |ΔEH t12 |=|YES t1 -HE t2 | Where EH t1 is the total amplitude of even harmonics at time t1; EH t2 is the total amplitude of even harmonics at time t2; If |ΔI t12 |>θ2 then α=1, if |ΔI t12 |≤θ2, then α=0, θ2 is the set current change threshold, and α is the current mutation amplitude dimension; If σI t123 >θ3 then β=1, if σI t123 ≤θ3, then β=0, θ3 is the set current variance threshold, and β is the current variance amplitude dimension; If ΔP t12 >θ4 then χ=1, if ΔP t12 ≤θ4, then χ=0, θ4 is the set power mutation threshold, and χ is the power mutation amplitude dimension; If |ΔOH t12 |>θ5 then δ=1, if |ΔOH t12 |≤θ5, then δ=0, θ5 is the set odd harmonic mutation amplitude, and δ is the odd harmonic mutation amplitude dimension; If |ΔEH t12 |>θ6 then ε=1, if |ΔEH t12 |≤θ6, then ε=0, θ6 is the set even harmonic mutation amplitude, and ε is the even harmonic mutation amplitude dimension; S5. A secondary determination of the arc fault risk of the target distribution power line is performed based on the dimension determination value obtained in step S4; S6. Based on the determination result obtained in step S5, the hidden danger determination of the arc fault in the target power distribution line is completed.

2. The method for determining arc fault hazards in distribution power lines according to claim 1 is characterized in that The real-time acquisition of data information of the target power distribution line described in step S1 specifically includes the following steps: According to the set sampling frequency, the voltage data, current data, power data, power factor data and line harmonic data of the target power distribution line are obtained.

3. The method for determining arc fault hazards in distribution power lines according to claim 2 is characterized in that The step S2 of calculating the change amount of each data according to the data information obtained in step S1 specifically includes the following steps: Use the following formula to calculate the current change amplitude ΔI t12 : ΔI t12 =I t1 -I t2 Where I t1 is the current amplitude at time t1; I t2 is the current amplitude at time t2; time t1 and time t2 are adjacent times; Use the following formula to calculate the odd harmonic change amplitude ΔOH t12 : ΔOH t12 =|OH t1 -OH t2 | Where OH t1 is the total amplitude of odd harmonics at time t1; OH t2 is the total amplitude of odd harmonics at time t2; Use the following formula to calculate the even harmonic change amplitude ΔEH t12 : ΔEH t12 [|YES t1 -HE t2 | Where EH t1 is the total amplitude of even harmonics at time t1; EH t2 is the total amplitude of even harmonics at time t2.

4. The method for determining arc fault hazards in distribution power lines according to claim 3 is characterized in that The step S3 of performing a primary determination of arc fault hazards in the target distribution power line based on the variation data obtained in step S2 specifically includes the following steps: The primary determination index ILFDM of arc fault hazards of the target distribution power line is calculated using the following formula: ILFDM=k1ΔI t12 +k2ΔOH t12 +k3ΔEH t12 Where k1 is the first weight coefficient; k2 is the second weight coefficient; k3 is the third weight coefficient; Based on the obtained ILFDM, the following rules are used to make a primary judgment on the arc fault hazard of the target distribution power line: If ILFDM>θ1, it is preliminarily determined that the target power distribution line has a fault arc hazard, and subsequent steps are carried out; θ1 is the set primary threshold; If ILFDM≤θ1, it is preliminarily determined that there is no arc fault hazard in the target power distribution line, and the algorithm ends.

5. The method for determining arc fault hazards in distribution power lines according to claim 4 is characterized in that The step S5, based on the dimension determination value obtained in step S4, performs a secondary determination of the arc fault hazard of the target distribution power line, specifically comprising the following steps: The secondary determination index FLFDM of arc fault hazards of the target distribution power line is calculated using the following formula: FLFDM=m1FLFDM1+m2FLFDM2 Where m1 is the time domain diagnosis weight coefficient; m2 is the frequency domain diagnosis weight coefficient; FLFDM1 is the time domain diagnosis index, and FLFDM1 = a1α + a2β + a3χ, a1 is the current change weight coefficient, a2 is the current variance weight coefficient, and a3 is the power mutation weight coefficient; FLFDM2 is the frequency domain diagnosis index, and FLFDM2 = a4δ + a5ε, a4 is the odd harmonic weight coefficient, and a5 is the even harmonic weight coefficient; According to the obtained FLFDM, a secondary determination of the arc fault hazard of the target power distribution line is performed: If FLFDM≤TT1, it is determined that there is no arc fault hazard in the target power distribution line; If TT1<FLFDM<TT2, proceed to the next round of judgment; If FLFDM≥TT2, it is determined that the target power distribution line has a fault arc hazard; If the judgment results of two consecutive rounds are both TT1<FLFDM<TT2, it is determined that there is a fault arc hazard in the target power distribution line.

6. A system for implementing the method for determining arc fault hazards in distribution power lines according to any one of claims 1 to 5, characterized in that It includes a data acquisition module, a change calculation module, a primary determination module, a dimension calculation module, a secondary determination module and a hidden danger determination module; the data acquisition module, the change calculation module, the primary determination module, the dimension calculation module, the secondary determination module and the hidden danger determination module are connected in series in sequence; the data acquisition module is used to obtain data information of the target power distribution line in real time and upload the data information to the change calculation module; The change calculation module is used to calculate the change amount of each data based on the received data information and the acquired data information, and upload the data information to the primary judgment module; The primary determination module is used to make a primary determination of the arc fault hazard of the target power distribution line based on the received data information and the obtained variation data, and upload the data information to the dimension calculation module; The dimension calculation module is used to calculate the dimension determination value of the change amount of each data based on the received data information, the obtained determination result and the acquired data information, and upload the data information to the secondary determination module; the secondary determination module is used to perform a secondary determination of the arc fault hazard of the target power distribution line based on the received data information and the obtained dimension determination value, and upload the data information to the hazard determination module; The hidden danger determination module is used to complete the hidden danger determination of the arc fault of the target power distribution line according to the received data information and the obtained determination results.

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