Transmission line fault positioning method and system based on traveling wave detection

Abstract

The invention discloses a power transmission line fault positioning method and system based on traveling wave detection, and the method comprises the steps: carrying out the Clark transformation of a three-phase voltage continuous signal corresponding to a measurement end, and obtaining two line mode components; the two line mode components are subjected to conversion considering a grounding short circuit fault and an interphase short circuit fault at the same time, and a continuous reference signal used for traveling wave detection is obtained; straight line fitting is carried out on the sampling points in the two time sequence sliding windows, and traveling wave detection is carried out by taking the sudden change moment of the included angle between the two obtained straight lines as the traveling wave detection time when the traveling wave arrives at the measuring end of the power transmission line; and carrying out power transmission line fault positioning based on the traveling wave detection time. The method only relates to time domain analysis, so that the aliasing phenomenon caused by complex time-frequency domain analysis in the prior art is avoided, and meanwhile, the calculation complexity is relatively low.

Description

Technical Field

[0001] The present invention belongs to the technical field of transmission line fault location, and in particular, relates to a transmission line fault location method and system based on traveling wave detection. Background Art

[0002] Accurate transmission line fault location can reduce power system restoration time, related costs and economic losses. Fault location in power grids is usually carried out through three methods: impedance-based method, traveling wave-based fault location and artificial intelligence-based method. The impedance-based method uses the power frequency components of voltage and current, requires solving a complex set of nonlinear equations, and it is difficult to completely eliminate the interference of "pseudo-roots", which may lead to long protection time and the occurrence of protection misoperation. Due to the lack of interpretability, the feasibility of large-scale application of artificial intelligence / machine learning methods in the field of power grid security still needs further demonstration.

[0003] In recent years, with the advancement of signal processing technology, the possibility of sampling signals at high frequencies, and the development of optical sensors, fault location methods based on traveling waves have received more attention. An important aspect of traveling wave location is to extract the time it takes for the traveling wave to reach the end of the transmission line where the measuring equipment is installed. There have been some research results on this issue, but most of the existing results are based on more complex signal processing algorithms, and some algorithms also involve time-frequency domain analysis, such as Hilbert-Huang transform, S transform, etc. At present, the problems that may arise when using these methods include: the existence of aliasing, excessive sensitivity to noise, and excessive computational burden.

[0004] Therefore, how to propose a transmission line fault location method and system based on traveling wave detection that does not require complex time-frequency domain analysis to avoid aliasing and improve noise tolerance caused by harmonics is an urgent problem to be solved by technical personnel in this field. Summary of the invention

[0005] In order to solve the problems existing in the prior art, the present invention proposes a transmission line fault location method and system based on traveling wave detection.

[0006] The technical solution of the present invention is as follows:

[0007] A transmission line fault location method based on traveling wave detection, the transmission line is provided with a measuring terminal for measuring a three-phase voltage signal, comprising:

[0008] The three-phase voltage continuous signal corresponding to the measuring end is subjected to Clark transformation to obtain two line mode components;

[0009] The two line mode components are transformed by simultaneously considering the ground short circuit fault and the phase short circuit fault to obtain a continuous reference signal;

[0010] Performing straight line fitting on the sampling points in two adjacent time sliding windows moving with the continuous reference signal respectively, and taking the moment of the sudden change of the angle between the two straight lines as the traveling wave detection time when the traveling wave arrives at the measuring end of the transmission line to perform traveling wave detection;

[0011] Based on the traveling wave detection time, transmission line fault location is performed.

[0012] Furthermore, the specific method of performing Clark transformation on the three-phase voltage continuous signal corresponding to the measuring end to obtain two line mode components is:

[0013] The Clark transformation is performed using the following formula:

[0014]

[0015] In the formula, u a (t),u b (t),u c (t) are the instantaneous values ​​of phase a voltage, phase b voltage and phase c voltage corresponding to the measuring end at time t; u α (t) and u β (t) are respectively the Clark transform of u a (t),u b (t),u c (t) The instantaneous values ​​of the α-mode and β-mode obtained after conversion at time t.

[0016] Furthermore, the specific method of converting the two line mode components while taking into account the ground short circuit fault and the phase short circuit fault to obtain the continuous reference signal is:

[0017] The conversion of ground short circuit fault and phase short circuit fault is carried out by the following formula:

[0018] u αβ (t) = u α (t)+u β (t)=(x(t),y(t))

[0019] Among them, u αβ (t) is the continuous reference signal; x(t) and y(t) are u αβ (t) is the horizontal and vertical coordinates.

[0020] Furthermore, the specific method of performing straight line fitting on the sampling points in two adjacent time sliding windows moving with the continuous reference signal, and taking the sudden change moment of the angle between the two straight lines as the traveling wave detection time when the traveling wave arrives at the measurement end of the transmission line for traveling wave detection is:

[0021] Preset two sequential sliding windows that are adjacent to each other on the time axis, which are respectively recorded as a first window that lags behind in time and a second window that advances in time;

[0022] Allowing the first window and the second window to move with the continuous reference signal, wherein the sampling points captured by the first window and the second window dynamically change with the movement of the first window and the second window;

[0023] Each time the first window and the second window move, the sampling points captured by the first window and the second window are fitted with a straight line, and the change in the angle between the two straight lines is monitored. The moment when the change in the angle between the two straight lines is greater than or equal to the set angle threshold is recorded as the mutation moment, thereby obtaining the traveling wave detection time; wherein, the straight line equation obtained by fitting is:

[0024] L1:y(t)=a1x(t)+b0

[0025] L2:y(t)=a2x(t)+b0

[0026] Where, L1 and L2 represent the linear equations obtained by fitting the first window and the second window respectively; a1 and a2 represent the slopes of L1 and L2 respectively; b0 is the common intercept of L1 and L2;

[0027] The slope a1 of L1 and the slope a2 of L2 are obtained as follows:

[0028]

[0029] The angle between the two straight lines is obtained as follows:

[0030] θ=π-tan -1 (a1)-tan -1 (a2)

[0031] Where θ is the angle between the straight lines L1 and L2.

[0032] Furthermore, a width ratio of the first window to the second window is 2:1.

[0033] Furthermore, the specific method for locating a transmission line fault based on the traveling wave detection time includes:

[0034] The first three traveling wave detection times are obtained, and the fault sound location is determined based on the first three traveling wave detection times, and the distance between the fault point and the measurement end of the transmission line is calculated.

[0035] Furthermore, the specific method of determining the fault sound location based on the first three traveling wave detection times and calculating the distance between the fault point and the measurement end of the transmission line includes:

[0036] S31, the first three traveling wave detection times are respectively the first traveling wave detection time t1, the second traveling wave detection time t2 and the third traveling wave detection time t3; based on the first traveling wave detection time t1 and the second traveling wave detection time t2, the distance from the fault point to the measurement end is calculated when the fault occurs in the first half area and the second half area;

[0037] The method for calculating the distance from the fault point to the measuring end based on the first traveling wave detection time t1 and the second traveling wave detection time t2 when the fault is assumed to occur in the first half area and the second half area is as follows:

[0038]

[0039] Where, d1 and d2 are the distances from the fault point to the measurement end when the fault occurs in the first half and the second half, respectively; v is the speed of the traveling wave propagating in the transmission line; l is the total length of the transmission line where the fault is located;

[0040] S32, based on the distance from the fault point to the measuring end when the assumed fault occurs in the first half and the second half, determine the dead zone range constraint of the midpoint of the transmission line. If the dead zone range constraint of the midpoint of the transmission line is satisfied, (d1+d2) / 2 is used as the distance from the fault point to the measuring end of the transmission line and go to step S34; otherwise, go to step S33;

[0041] The expression of the dead zone range constraint at the midpoint of the transmission line is:

[0042] |d1-d2|≤v·F

[0043] Where F is the sampling frequency;

[0044] S33, calculate the theoretical time for the traveling wave to arrive at the measuring end of the transmission line for the third time when the fault occurs in the front half and the rear half of the transmission line according to the following formula, and compare the theoretical time for the third time to arrive at the measuring end of the transmission line with the third traveling wave detection time t3. If If the fault occurs in the first half of the area, d1 is used as the distance between the fault point and the transmission line measurement end; otherwise, the fault occurs in the first half of the area, d2 is used as the distance between the fault point and the transmission line measurement end. The calculation formula for the theoretical time when the traveling wave reaches the transmission line measurement end for the third time is as follows:

[0045]

[0046] in, is the theoretical time when the traveling wave reaches the measuring end of the transmission line for the third time when the fault occurs in the first half of the area; is the theoretical time when the traveling wave reaches the measuring end of the transmission line for the third time when the fault occurs in the second half;

[0047] S34. Output the calculated distance between the fault point and the measuring end of the transmission line to complete the fault location work.

[0048] A transmission line fault location system based on traveling wave detection, the transmission line is provided with a measuring terminal for measuring a three-phase voltage signal, including a line mode component acquisition module, a continuous reference signal acquisition module, a traveling wave detection module and a fault location module;

[0049] The line mode component acquisition module is used to perform Clark transformation on the three-phase voltage continuous signal corresponding to the measuring end to obtain two line mode components;

[0050] The continuous reference signal acquisition module is used to transform the two line mode components while taking into account the ground short circuit fault and the phase short circuit fault, so as to obtain a continuous reference signal;

[0051] The traveling wave detection module is used to perform straight line fitting on the sampling points in two adjacent time sliding windows moving with the continuous reference signal, and use the sudden change moment of the angle between the two straight lines as the traveling wave detection time when the traveling wave arrives at the measurement end of the transmission line to perform traveling wave detection;

[0052] The fault locating module is used to locate the fault of the power transmission line based on the traveling wave detection time.

[0053] An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor is used to call and run the computer program stored in the memory to execute any of the methods described above.

[0054] A computer-readable storage medium stores a computer program, wherein the computer program implements the steps of any of the above methods when executed by a processor.

[0055] Compared with the prior art, the present invention has the following beneficial effects:

[0056] The present invention proposes a transmission line fault location method and system based on traveling wave detection. The method performs Clark transformation on the continuous three-phase voltage signal corresponding to the measuring end to obtain two line mode components; the two line mode components are transformed by simultaneously considering the ground short circuit fault and the phase-to-phase short circuit fault to obtain a continuous reference signal for traveling wave detection; then the sampling points in the two time series sliding windows are respectively fitted with straight lines, and the sudden change moment of the angle between the two straight lines is used as the traveling wave detection time when the traveling wave arrives at the measuring end of the transmission line for traveling wave detection; based on the traveling wave detection time, the transmission line fault is located. The method only involves time domain analysis, avoids the aliasing phenomenon caused by the complex time-frequency domain analysis in the prior art, and has low computational complexity.

[0057] The method of the present invention reduces the influence of a single sample point by performing straight line fitting on the sampling points in two adjacent time sliding windows moving with the continuous reference signal, so that the method of the present invention has strong tolerance to noise caused by harmonics.

[0058] The continuous reference signal used for traveling wave detection in the method of the present invention is obtained by transforming two line mode components while taking into account the ground short circuit fault and the phase-to-phase short circuit fault, so the fault is considered more comprehensively.

[0059] In the context of large-scale access to new energy power generation, energy storage and other equipment in new power systems, the harmonics introduced by power electronic devices have a greater impact on traditional fault location algorithms. The method of the present invention has high robustness, can provide algorithm support for fault location in power systems, and is helpful for rapid troubleshooting and improved power supply reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 Flow chart of a transmission line fault location method based on traveling wave detection in an embodiment.

[0061] Figure 2 Schematic diagram of the traveling wave transmission path when a fault occurs in the front half of the transmission line in the embodiment.

[0062] Figure 3 In the embodiment, when the fault occurs in the front half of the transmission line, u αβ (t) waveform diagram.

[0063] Figure 4 Schematic diagram of the traveling wave transmission path when a fault occurs in the second half of the transmission line in the embodiment.

[0064] Figure 5 is the case where the fault occurs in the second half of the transmission line in the embodiment αβ (t) waveform diagram. DETAILED DESCRIPTION

[0065] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent modifications of the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0066] Embodiment 1:

[0067] The present invention provides a transmission line fault location method based on traveling wave detection, wherein the transmission line is provided with a measuring end for measuring a three-phase voltage signal, and the measuring end is an end point in the transmission line, comprising:

[0068] The three-phase voltage continuous signal corresponding to the measuring end is subjected to Clark transformation to obtain two line mode components;

[0069] The two line mode components are transformed by simultaneously considering the ground short circuit fault and the phase short circuit fault to obtain a continuous reference signal for traveling wave detection;

[0070] Straight line fitting is performed on the sampling points in two adjacent time sliding windows moving with the continuous reference signal, and the sudden change moment of the angle between the two straight lines is used as the traveling wave detection time when the traveling wave arrives at the measuring end of the transmission line for traveling wave detection; the two adjacent time sliding windows are seamlessly connected, and there is no sample point between the two time sliding windows.

[0071] Transmission line fault location is performed based on traveling wave detection time.

[0072] Embodiment 2:

[0073] This embodiment is further designed on the basis of the first embodiment in that, in this embodiment, the three-phase voltage continuous signal corresponding to the measuring end is subjected to Clark transformation to obtain two line mode components in the following specific method:

[0074] Clark transformation is performed using the following formula:

[0075]

[0076] In the formula, u a (t),u b (t),u c (t) are the instantaneous values ​​of the a-phase voltage, b-phase voltage, and c-phase voltage corresponding to the measuring end at time t, which will change with time; u α (t) and u β (t) are respectively the Clark transform of u a (t),u b (t),u c (t) The instantaneous values ​​of the α-mode and β-mode obtained after conversion at time t.

[0077] Embodiment three:

[0078] This embodiment is further designed on the basis of the second embodiment in that, in this embodiment, the two line mode components are transformed by considering both the ground short circuit fault and the phase short circuit fault, and the specific method for obtaining the continuous reference signal is:

[0079] The conversion of ground short circuit fault and phase short circuit fault is carried out by the following formula:

[0080] u αβ (t) = u α (t)+u β(t)=(x(t),y(t))

[0081] Among them, u αβ (t) is the continuous reference signal (the sum of the line mode components); x(t) and y(t) are u αβ (t) is the horizontal and vertical coordinates.

[0082] Embodiment 4:

[0083] This embodiment is further designed on the basis of the first embodiment in that, in this embodiment, straight line fitting is performed on the sampling points in two adjacent time sliding windows moving with the continuous reference signal, and the specific method for performing traveling wave detection is to use the moment of the sudden change of the angle between the two straight lines as the traveling wave detection time when the traveling wave arrives at the measurement end of the transmission line:

[0084] Preset two sequential sliding windows that are adjacent to each other on the time axis, which are respectively recorded as a first window that lags behind in time and a second window that advances in time;

[0085] The first window and the second window are made to move with the continuous reference signal, and the sampling points captured by the first window and the second window are dynamically changed with the movement of the first window and the second window;

[0086] Each time the first window and the second window move, the sampling points captured by the first window and the second window are fitted with a straight line, and the change in the angle between the two straight lines is monitored. The moment when the change in the angle between the two straight lines is greater than or equal to the set angle threshold is recorded as the mutation moment, thereby obtaining the traveling wave detection time; wherein, the straight line equation obtained by fitting is:

[0087] L1:y(t)=a1x(t)+b0

[0088] L2:y(t)=a2x(t)+b0

[0089] Where, L1 and L2 represent the linear equations obtained by fitting the first window and the second window respectively; a1 and a2 represent the slopes of L1 and L2 respectively; b0 is the common intercept of L1 and L2;

[0090] The slope a1 of L1 and the slope a2 of L2 are obtained as follows:

[0091]

[0092] The angle between two straight lines is given by:

[0093] θ=π-tan -1 (a1)-tan -1 (a2)

[0094] Where θ is the angle between the straight lines L1 and L2.

[0095] Embodiment five:

[0096] This embodiment is further designed on the basis of the fourth embodiment in that the width ratio of the first window to the second window is 2: 1. For example, the width of the first window and the width of the second window are respectively the width of 10 sampling points and the width of 5 sampling points.

[0097] Embodiment six:

[0098] This embodiment is further designed on the basis of the fourth embodiment in that the specific method for locating the transmission line fault based on the traveling wave detection time in this embodiment includes:

[0099] The first three traveling wave detection times are obtained, and the fault sound location is determined based on the first three traveling wave detection times, and the distance between the fault point and the measurement end of the transmission line is calculated.

[0100] Embodiment seven:

[0101] This embodiment is further designed on the basis of the fifth embodiment in that the specific method for determining the fault sound location and calculating the distance between the fault point and the measurement end of the transmission line according to the first three traveling wave detection times in this embodiment includes:

[0102] S31, the first three traveling wave detection times are respectively the first traveling wave detection time t1, the second traveling wave detection time t2 and the third traveling wave detection time t3; based on the first traveling wave detection time t1 and the second traveling wave detection time t2, the distances from the fault point (two candidate fault points) to the measuring end are calculated when the fault is assumed to occur in the first half (measuring end-middle point of the transmission line) and the second half (relative to the middle point of the transmission line);

[0103] The calculation method of the distance from the fault point to the measurement end when the fault occurs in the first half area and the second half area based on the first traveling wave detection time t1 and the second traveling wave detection time t2 is as follows:

[0104]

[0105] Where, d1 and d2 are the distances from the fault point to the measurement end when the fault occurs in the first half and the second half, respectively; v is the speed of traveling waves propagating in the transmission line, that is, the traveling wave transmission speed; l is the total length of the transmission line where the fault is located;

[0106] S32, based on the distance from the fault point to the measuring end when the fault is assumed to occur in the first half and the second half, determine the dead zone range constraint of the midpoint of the transmission line. If the dead zone range constraint of the midpoint of the transmission line is satisfied, (d1+d2) / 2 is used as the distance from the fault point to the measuring end of the transmission line and go to step S34, otherwise go to step S33;

[0107] The expression of the dead zone range constraint at the midpoint of the transmission line is:

[0108] |d1-d2|≤v·F

[0109] Where F is the sampling frequency;

[0110] S33, calculate the theoretical time for the traveling wave to arrive at the measuring end of the transmission line for the third time when the fault occurs in the front half and the rear half of the transmission line according to the following formula, and compare the theoretical time for the third time to arrive at the measuring end of the transmission line with the third traveling wave detection time t3. If If the fault occurs in the first half of the area, d1 is used as the distance between the fault point and the transmission line measurement end; otherwise, the fault occurs in the first half of the area, d2 is used as the distance between the fault point and the transmission line measurement end. The calculation formula for the theoretical time when the traveling wave reaches the transmission line measurement end for the third time is as follows:

[0111]

[0112] in, is the theoretical time when the traveling wave reaches the measuring end of the transmission line for the third time when the fault occurs in the first half of the area; is the theoretical time when the traveling wave reaches the measuring end of the transmission line for the third time when the fault occurs in the second half;

[0113] S34. Output the calculated distance between the fault point and the measuring end of the transmission line to complete the fault location work.

[0114] Embodiment eight:

[0115] A transmission line fault location system based on traveling wave detection of the present invention, the transmission line is provided with a measuring end for measuring a three-phase voltage signal, the measuring end is an end point in the transmission line, and is characterized in that it comprises a line mode component acquisition module, a continuous reference signal acquisition module, a traveling wave detection module and a fault location module;

[0116] A line mode component acquisition module is used to perform Clark transformation on the three-phase voltage continuous signal corresponding to the measuring end to obtain two line mode components;

[0117] A continuous reference signal acquisition module is used to convert two line mode components while taking into account the ground short circuit fault and the phase short circuit fault to obtain a continuous reference signal;

[0118] A traveling wave detection module is used to perform straight line fitting on the sampling points in two adjacent time sliding windows moving with the continuous reference signal, and to perform traveling wave detection by taking the moment of the sudden change of the angle between the two straight lines as the traveling wave detection time when the traveling wave arrives at the measurement end of the transmission line;

[0119] The fault location module is used to locate the transmission line fault based on the traveling wave detection time.

[0120] Embodiment nine:

[0121] An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor is used to call and run the computer program stored in the memory to execute any of the methods described above.

[0122] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of any of the above methods are implemented.

[0123] Application Example 1:

[0124] In this example, a transmission line fault location method based on traveling wave detection of the present invention is implemented on a certain transmission line. The simulated fault occurs in the front half of the transmission line, 25 km away from the A end. Figure 2 As shown. The corresponding continuous reference signal u is the sum of the line mode components αβ The waveform of (t) is as follows Figure 3 shown.

[0125] The two adjacent time sliding windows moving with the continuous reference signal are referred to as window 1 and window 2. Figure 3 The angle between the two straight lines L1 and L2 fitted by the samples in the middle window 1 and window 2 can monitor and identify the time when the traveling wave reaches the A end three times after the fault occurs, that is, t1 = 89μs, t2 = 258μs, and t3 = 430μs.

[0126] Calculate d1 and d2 based on t1 and t2, and get d1=25.10km, d2=124.90km.

[0127] Obviously, the gap between d1 and d2 is large, which does not meet the dead zone range constraint of the midpoint of the transmission line. The fault did not occur at the midpoint of the transmission line, but it is impossible to determine whether the fault occurred at a distance of d1 or d2 from end A. It is necessary to further introduce t3 as an auxiliary criterion.

[0128] Further calculations yield Obviously, of the two It is closer to t3, so it is judged that the fault should occur in the front half of the transmission line, and the distance between the fault point and end A is about 25.10 km. Compared with the simulated fault location of 25 km, there is only a 0.40% error, which shows that the transmission line fault location method of the present invention has high accuracy.

[0129] Application Example 2:

[0130] In this example, a transmission line fault location method based on traveling wave detection of the present invention is implemented on a certain transmission line. The simulated fault occurs in the front half of the transmission line, 125 km away from the A end. Figure 4 As shown. The corresponding continuous reference signal u is the sum of the line mode components αβ The waveform of (t) is as follows Figure 5 shown.

[0131] Similarly, the method based on dual-sequence sliding windows and straight-line fitting of the present invention can be used to identify the time when the traveling wave reaches the A end three times after the fault occurs, that is, t1=431μs, t2=603μs, and t3=775μs.

[0132] Calculate d1 and d2 based on t1 and t2, and get d1=25.54km, d2=124.46km.

[0133] Similarly, the difference between d1 and d2 is large, which does not meet the dead zone range constraint of the transmission line midpoint. The fault does not occur at the midpoint of the transmission line, but it is impossible to determine whether the fault occurred at a distance of d1 or d2 from end A. It is necessary to further introduce t3 as an auxiliary criterion.

[0134] Further calculations yield Obviously, of the two It is closer to t3, so it is judged that the fault should occur in the second half of the transmission line, and the distance between the fault point and end A is about 124.46 km. Compared with the actual fault location of 125 km, there is only a 0.43% error, which shows that the transmission line fault location method of the present invention has high accuracy.

[0135] The above description is only a specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a technician familiar with the technical field within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention.

Claims

1. A transmission line fault location method based on traveling wave detection, wherein the transmission line is provided with a measuring terminal for measuring a three-phase voltage signal, characterized in that: include: The three-phase voltage continuous signal corresponding to the measuring end is subjected to Clark transformation to obtain two line mode components; The two line mode components are transformed by simultaneously considering the ground short circuit fault and the phase short circuit fault to obtain a continuous reference signal; Performing straight line fitting on the sampling points in two adjacent time sliding windows moving with the continuous reference signal respectively, and taking the moment of the sudden change of the angle between the two straight lines as the traveling wave detection time when the traveling wave arrives at the measuring end of the transmission line to perform traveling wave detection; Based on the traveling wave detection time, transmission line fault location is performed.

2. The transmission line fault location method based on traveling wave detection according to claim 1 is characterized in that: The specific method of performing Clark transformation on the three-phase voltage continuous signal corresponding to the measuring end to obtain two line mode components is as follows: The Clark transformation is performed using the following formula: In the formula, u a (t),u b (t),u c (t) are the instantaneous values ​​of phase a voltage, phase b voltage and phase c voltage corresponding to the measuring end at time t; u α (t) and u β (t) are respectively the Clark transform of u a (t),u b (t),u c (t) The instantaneous values ​​of the α-mode and β-mode obtained after conversion at time t.

3. The method for locating a transmission line fault based on traveling wave detection according to claim 2, characterized in that: The specific method of converting the two line mode components by simultaneously considering the ground short circuit fault and the phase short circuit fault to obtain the continuous reference signal is: The conversion of ground short circuit fault and phase short circuit fault is carried out by the following formula: u αβ (t)=u α (t)+u β (t)=(x(t),y(t)) Among them, u αβ (t) is the continuous reference signal; x(t) and y(t) are u αβ (t) is the horizontal and vertical coordinates.

4. The method for locating a transmission line fault based on traveling wave detection according to claim 1, characterized in that: The specific method of performing straight line fitting on the sampling points in two adjacent time sliding windows moving with the continuous reference signal, and taking the moment of the sudden change of the angle between the two straight lines as the traveling wave detection time when the traveling wave arrives at the measurement end of the transmission line for traveling wave detection is: Preset two sequential sliding windows that are adjacent to each other on the time axis, which are respectively recorded as a first window that lags behind in time and a second window that advances in time; Allowing the first window and the second window to move with the continuous reference signal, wherein the sampling points captured by the first window and the second window dynamically change with the movement of the first window and the second window; Each time the first window and the second window move, the sampling points captured by the first window and the second window are fitted with a straight line, and the change in the angle between the two straight lines is monitored. The moment when the change in the angle between the two straight lines is greater than or equal to the set angle threshold is recorded as the mutation moment, thereby obtaining the traveling wave detection time; wherein, the straight line equation obtained by fitting is: L1:y(t)=a1x(t)+b0 L2:y(t)=a2x(t)+b0 Where, L1 and L2 represent the linear equations obtained by fitting the first window and the second window respectively; a1 and a2 represent the slopes of L1 and L2 respectively; b0 is the common intercept of L1 and L2; The slope a1 of L1 and the slope a2 of L2 are obtained as follows: The angle between the two straight lines is obtained as follows: θ=π-time -1 (a1)-except -1 (a2) Where θ is the angle between the straight lines L1 and L2.

5. The method for locating power transmission line faults based on traveling wave detection according to claim 4, characterized in that: The width ratio of the first window to the second window is 2:

1.

6. The method for locating power transmission line faults based on traveling wave detection according to claim 4, characterized in that: The specific method for locating a transmission line fault based on the traveling wave detection time includes: The first three traveling wave detection times are obtained, and the fault sound location is determined based on the first three traveling wave detection times, and the distance between the fault point and the measurement end of the transmission line is calculated.

7. The method for locating power transmission line faults based on traveling wave detection according to claim 6, characterized in that: The specific method of determining the fault sound location based on the first three traveling wave detection times and calculating the distance between the fault point and the transmission line measurement end includes: S31, the first three traveling wave detection times are respectively the first traveling wave detection time t1, the second traveling wave detection time t2 and the third traveling wave detection time t3; based on the first traveling wave detection time t1 and the second traveling wave detection time t2, the distance from the fault point to the measurement end is calculated when the fault occurs in the first half area and the second half area; The method for calculating the distance from the fault point to the measuring end based on the first traveling wave detection time t1 and the second traveling wave detection time t2 when the fault is assumed to occur in the first half area and the second half area is as follows: Where d1 and d2 are the distances from the fault point to the measurement end when the fault occurs in the first half and the second half respectively; v is the speed of the traveling wave propagating in the transmission line; l is the total length of the transmission line where the fault is located; S32, based on the distance from the fault point to the measuring end when the assumed fault occurs in the first half and the second half, determine the dead zone range constraint of the midpoint of the transmission line. If the dead zone range constraint of the midpoint of the transmission line is satisfied, (d1+d2) / 2 is used as the distance from the fault point to the measuring end of the transmission line and go to step S34; otherwise, go to step S33; The expression of the dead zone range constraint at the midpoint of the transmission line is: |d1-d2|≤v·F Where F is the sampling frequency; S33, calculate the theoretical time for the traveling wave to arrive at the measuring end of the transmission line for the third time when the fault occurs in the front half and the rear half of the transmission line according to the following formula, and compare the theoretical time for the third time to arrive at the measuring end of the transmission line with the third traveling wave detection time t3. If If the fault occurs in the first half of the area, d1 is used as the distance between the fault point and the transmission line measurement end; otherwise, the fault occurs in the first half of the area, d2 is used as the distance between the fault point and the transmission line measurement end. The calculation formula for the theoretical time when the traveling wave reaches the transmission line measurement end for the third time is as follows: in, is the theoretical time when the traveling wave reaches the measuring end of the transmission line for the third time when the fault occurs in the first half of the area; is the theoretical time when the traveling wave reaches the measuring end of the transmission line for the third time when the fault occurs in the second half; S34. Output the calculated distance between the fault point and the measuring end of the transmission line to complete the fault location work.

8. A transmission line fault location system based on traveling wave detection, the transmission line is provided with a measuring terminal for measuring a three-phase voltage signal, characterized in that: It includes a line mode component acquisition module, a continuous reference signal acquisition module, a traveling wave detection module and a fault location module; The line mode component acquisition module is used to perform Clark transformation on the three-phase voltage continuous signal corresponding to the measuring end to obtain two line mode components; The continuous reference signal acquisition module is used to transform the two line mode components while taking into account the ground short circuit fault and the phase short circuit fault, so as to obtain a continuous reference signal; The traveling wave detection module is used to perform straight line fitting on the sampling points in two adjacent time sliding windows moving with the continuous reference signal, and use the sudden change moment of the angle between the two straight lines as the traveling wave detection time when the traveling wave arrives at the measurement end of the transmission line to perform traveling wave detection; The fault locating module is used to locate the fault of the power transmission line based on the traveling wave detection time.

9. An electronic device, characterized in that: The electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor is configured to call and run the computer program stored in the memory to execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method as claimed in any one of claims 1 to 7 are implemented.

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