Power distribution network fault locating method, device and equipment and storage medium

Abstract

The application discloses a distribution network fault positioning method, device and equipment and a storage medium. The method obtains traveling wave data of two traveling waves of a distribution network, and finds the subscript of a mutation maximum value of the two traveling wave sequences. A traveling wave slope list is calculated according to the traveling wave data and the subscript of the mutation maximum value. A traveling wave wave head position is found according to the traveling wave slope list. A fault point position is determined according to the traveling wave wave head position, a first point time of the traveling wave, a device sampling rate and the distance between two devices. The method can reduce the calculation amount and the calculation time, involves few variables, introduces few errors, improves the accuracy of fault positioning, and improves the speed and efficiency of distribution network fault positioning.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric power, and in particular to a distribution network fault positioning method, device, equipment and storage medium. BACKGROUND

[0002] The fault positioning technology is theoretically feasible in the application of distribution network fault positioning. The existing method is to correct the wave head time of the first reference end by using the distance of the same direction substation from the first reference end and the time difference of the arrival time of the traveling wave at each substation. Then, the fault point position is obtained by double-end positioning of the corrected wave head time and the different direction substation. Finally, the least square method is used to accurately locate the fault point. In this method, a large number of physical positions of substations and the arrival time of traveling waves are involved. However, due to the sag of the transmission line and the large number of nodes in the distribution network, the reflection and refraction have a great influence, and it is difficult to find the wave head of the traveling wave. Therefore, there is an error in the physical position between the substations, that is, in the actual line fault positioning application, it is found that there is a certain error between the positioning result and the line inspection result, which affects the fault positioning result. SUMMARY

[0003] The main purpose of the present application is to provide a distribution network fault positioning method, device, equipment and storage medium, which aims to solve the technical problems of large fault positioning error and low fault positioning accuracy in the prior art due to the sag of the transmission line and the large number of nodes in the distribution network, which leads to large reflection and refraction influence and difficulty in finding the wave head of the traveling wave.

[0004] In a first aspect, the present application provides a distribution network fault positioning method, which comprises the following steps:

[0005] Obtaining the traveling wave data of two traveling waves of the distribution network, and finding the subscript of the maximum mutation value of the two traveling wave sequences;

[0006] Calculating the traveling wave slope list according to the traveling wave data and the subscript of the maximum mutation value;

[0007] Finding the traveling wave head position according to the traveling wave slope list, and determining the fault point position according to the traveling wave head position, the first point time of the traveling wave, the device sampling rate and the distance between the two devices.

[0008] Optionally, the calculation of the traveling wave slope list according to the traveling wave data and the subscript of the maximum mutation value comprises:

[0009] The traveling wave slope list is calculated according to the traveling wave data and the subscript of the maximum mutation value by the following formula:

[0010] sx[i]=x[i+1]-x[i-1]

[0011] sy[i]=y[i+1]-y[i-1]

[0012] Wherein, sx is a slope list of the traveling wave x, sy is a slope list of the traveling wave y, x, y is traveling wave data, the subscript of the maximum mutation of the traveling wave x is xindex, the subscript of the maximum mutation of the traveling wave y is yindex, the length of the list sx is xindex, and the length of the list sy is yindex.

[0013] Optionally, the step of finding the traveling wave head position according to the traveling wave slope list, determining the fault point position according to the traveling wave head position, the first point time of the traveling wave, the device sampling rate and the distance between the two devices comprises:

[0014] The target list is obtained by using a preset list calculation formula on all points in the traveling wave slope list.

[0015] The current mutation confidence sequence is obtained according to the target list and a preset mutation confidence sequence calculation formula.

[0016] The current mutation confidence sequence is compared with a preset mutation confidence sequence threshold value, and the traveling wave head position is determined according to the comparison result.

[0017] The first point time of the traveling wave, the device sampling rate and the distance between the two devices are obtained, and the fault point position is determined according to the traveling wave head position, the first point time of the traveling wave, the device sampling rate and the distance between the two devices.

[0018] Optionally, the step of obtaining the target list by using a preset list calculation formula on all points in the traveling wave slope list comprises:

[0019] The target list is obtained by using the following preset list calculation formula on all points in the traveling wave slope list:

[0020]

[0021] Wherein, T(i) is the target list, E1(i) is the expected value of the subsequence from the starting point to the subscript i of the traveling wave, E2(i) is the expected value of the subsequence from the subscript i to the last point of the traveling wave, sd1 is the standard deviation of the subsequence from the starting point to the subscript i of the traveling wave, sd2 is the standard deviation of the subsequence from the subscript i to the last point of the traveling wave, N1 is the data length of the subsequence from the starting point to the subscript i of the traveling wave, and N2 is the data length of the subsequence from the subscript i to the last point of the traveling wave.

[0022] Optionally, the step of obtaining the current mutation confidence sequence according to the target list and a preset mutation confidence sequence calculation formula comprises:

[0023] The current mutation confidence sequence is obtained according to the target list and the following preset mutation confidence sequence calculation formula:

[0024]

[0025] wherein P(i) is the current mutation confidence sequence, T(i) is the target list, is an incomplete beta function, v = n - 2, n is the sequence length, and σ and η are constants.

[0026] Optionally, the comparing the current mutation confidence sequence with a preset mutation confidence sequence threshold and determining the traveling wave front position according to a comparison result comprises:

[0027] comparing the current mutation confidence sequence with a preset mutation confidence sequence threshold to generate a comparison result;

[0028] when the comparison result is that the current mutation confidence sequence does not exceed the preset mutation confidence sequence threshold, determining the traveling wave front position to be at a maximum value of the mutation;

[0029] when the comparison result is that the current mutation confidence sequence exceeds the preset mutation confidence sequence threshold, determining whether the subscript of the maximum value of the mutation exceeds a preset data length;

[0030] when the subscript of the maximum value of the mutation does not exceed the preset data length, taking a subsequence from a start point to a subscript at the wave front subscript as an input calculation list until a final subsequence length does not exceed the preset data length, and taking a first breakthrough point as the traveling wave front position.

[0031] Optionally, the obtaining a first point time of the traveling wave, a device sampling rate and a distance between two devices, and determining a fault point position according to the traveling wave front position, the first point time of the traveling wave, the device sampling rate and the distance between two devices comprises:

[0032] obtaining a first point time of the traveling wave, a device sampling rate and a distance between two devices;

[0033] determining the fault point position according to the traveling wave front position, the first point time of the traveling wave, the device sampling rate and the distance between two devices by the following formula:

[0034]

[0035] wherein dis is the fault point position, i.e. the distance between the fault point and the device collecting the traveling wave x, l0 is the distance between two devices, atime is the first sampling point time of the traveling wave x, btime is the first sampling point time of the traveling wave y, a point is the subscript of the wave front of the traveling wave x, b point is the subscript of the wave front of the traveling wave y, afs is the sampling frequency of the traveling wave x, bfs is the sampling frequency of the traveling wave y, and v is the wave velocity of the traveling wave.

[0036] In a second aspect, to achieve the above object, the present application provides a power distribution network fault locating device, which comprises:

[0037] a data acquisition module, configured to acquire traveling wave data of two traveling waves of the power distribution network, and find the subscript of the maximum mutation value of the two traveling wave sequences;

[0038] a list calculation module, configured to calculate a traveling wave slope list according to the traveling wave data and the subscript of the maximum mutation value;

[0039] a fault determination module, configured to find a traveling wave front position according to the traveling wave slope list, and determine a fault point position according to the traveling wave front position, a first point time of the traveling wave, a device sampling rate and a distance between two devices.

[0040] In a third aspect, to achieve the above object, the present application provides a power distribution network fault locating device, which comprises a memory, a processor and a power distribution network fault locating program stored in the memory and executable on the processor, and the power distribution network fault locating program is configured to implement the steps of the power distribution network fault locating method as described above.

[0041] In a fourth aspect, to achieve the above object, the present application provides a storage medium, which stores a power distribution network fault locating program, and the power distribution network fault locating program is executable on a processor to implement the steps of the power distribution network fault locating method as described above.

[0042] The power distribution network fault locating method provided by the present application can reduce the amount of calculation and the time of calculation, involve fewer variables, introduce fewer errors, improve the accuracy of fault locating, and improve the speed and efficiency of power distribution network fault locating. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 FIG. 1 is a device structure schematic diagram of a hardware running environment involved in an embodiment of the present application;

[0044] Figure 2 FIG. 2 is a flowchart of a first embodiment of the power distribution network fault locating method of the present application;

[0045] Figure 3 FIG. 3 is a flowchart of a second embodiment of the power distribution network fault locating method of the present application;

[0046] Figure 4This is a flowchart illustrating the third embodiment of the distribution network fault location method of the present invention;

[0047] Figure 5 This is a functional block diagram of the first embodiment of the power distribution network fault location device of the present invention.

[0048] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0049] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0050] The solution of this invention mainly involves: acquiring traveling wave data of two traveling waves in the distribution network, finding the index of the maximum abrupt change value of the two traveling wave sequences; calculating a traveling wave slope list based on the traveling wave data and the index of the maximum abrupt change value; finding the traveling wave head position based on the traveling wave slope list; and determining the fault location based on the traveling wave head position, the time of the first point of the traveling wave, the equipment sampling rate, and the distance between the two devices. This reduces the amount of calculation and calculation time, involves fewer variables, introduces fewer errors, improves the accuracy of fault location, and enhances the speed and efficiency of distribution network fault location. It solves the technical problem in the prior art where the sag of the transmission line and the large number of nodes in the distribution network lead to significant reflection and refraction effects, making it difficult to find the traveling wave head and resulting in large fault location errors and low fault location accuracy.

[0051] Reference Figure 1 , Figure 1 This is a schematic diagram of the device structure of the hardware operating environment involved in the embodiments of the present invention.

[0052] like Figure 1 As shown, the device may include: a processor 1001, such as a CPU; a communication bus 1002; a user interface 1003; a network interface 1004; and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display screen or an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface). The memory 1005 may be high-speed RAM or non-volatile memory, such as a disk drive. Optionally, the memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0053] Those skilled in the art will understand that Figure 1The device structure shown in the figures does not constitute a limitation on the device, and can include more or fewer components than shown, or combine certain components, or arrange different components.

[0054] As shown in Figure 1 The memory 1005 as a storage medium can include an operation device, a network communication module, a user interface module, and a network fault locating program.

[0055] The device of the application calls the network fault locating program stored in the memory 1005 through the processor 1001, and performs the following operations:

[0056] Obtain the traveling wave data of the two traveling waves of the network, and find the subscript of the maximum mutation of the two traveling wave sequences;

[0057] Calculate the traveling wave slope list according to the traveling wave data and the subscript of the maximum mutation;

[0058] Find the traveling wave head position according to the traveling wave slope list, and determine the fault point position according to the traveling wave head position, the first point time of the traveling wave, the device sampling rate, and the distance between the two devices.

[0059] The device of the application calls the network fault locating program stored in the memory 1005 through the processor 1001, and performs the following operations:

[0060] Calculate the traveling wave slope list according to the traveling wave data and the subscript of the maximum mutation by the following formula:

[0061] sx[i]=x[i+1]-x[i-1]

[0062] sy[i]=y[i+1]-y[i-1]

[0063] Where sx is the slope list of the traveling wave x, sy is the slope list of the traveling wave y, x, y is the traveling wave data, the subscript of the maximum mutation of the traveling wave x is xindex, the subscript of the maximum mutation of the traveling wave y is yindex, the length of the list sx is xindex, and the length of the list sy is yindex.

[0064] The device of the application calls the network fault locating program stored in the memory 1005 through the processor 1001, and performs the following operations:

[0065] Obtain the target list by a preset list calculation formula on all points in the traveling wave slope list;

[0066] Obtain the current mutation confidence sequence according to the target list and a preset mutation confidence sequence calculation formula;

[0067] The current mutation confidence sequence is compared with a preset mutation confidence sequence threshold, and a traveling wave wave front position is determined according to a comparison result.

[0068] A first point time of the traveling wave, a device sampling rate and a distance between two devices are acquired, and a fault point position is determined according to the traveling wave wave front position, the first point time of the traveling wave, the device sampling rate and the distance between two devices.

[0069] The device further performs the following operations by calling a power distribution network fault locating program stored in the memory 1005 through the processor 1001:

[0070] All points on the traveling wave slope list are obtained by a target list through a preset list calculation formula as follows:

[0071]

[0072] Wherein, T(i) is the target list, E1(i) is an expected value of the traveling wave from a starting point to a subsequence with index i, E2(i) is an expected value of the traveling wave from the subsequence with index i to a last point, sd1 is a standard deviation of the traveling wave from the starting point to the subsequence with index i, sd2 is a standard deviation of the traveling wave from the subsequence with index i to the last point, N1 is a data length of the traveling wave from the starting point to the subsequence with index i, and N2 is a data length of the traveling wave from the subsequence with index i to the last point.

[0073] The device further performs the following operations by calling a power distribution network fault locating program stored in the memory 1005 through the processor 1001:

[0074] A current mutation confidence sequence is obtained according to a preset mutation confidence sequence calculation formula according to the target list:

[0075]

[0076] Wherein, P(i) is the current mutation confidence sequence, T(i) is the target list, It is an incomplete beta function, v=n-2, n is a sequence length, and sigma and eta are constants.

[0077] The device further performs the following operations by calling a power distribution network fault locating program stored in the memory 1005 through the processor 1001:

[0078] The current mutation confidence sequence is compared with a preset mutation confidence sequence threshold, and a comparison result is generated;

[0079] When the comparison result is that the current mutation confidence sequence does not exceed the preset mutation confidence sequence threshold, the traveling wave wave front position is determined to be at a maximum value of the traveling wave mutation;

[0080] when the comparison result is that the current mutation confidence sequence exceeds the preset mutation confidence sequence threshold, determining whether the subscript of the mutation maximum value exceeds the preset data length;

[0081] when the subscript of the mutation maximum value does not exceed the preset data length, taking a subsequence from a starting point to a subscript of a wave head subscript as an input calculation list until a final subsequence length does not exceed the preset data length, and taking a first breakthrough point as a traveling wave wave head position.

[0082] The device of the application calls the network fault location program stored in the memory 1005 through the processor 1001, and further performs the following operations:

[0083] obtaining a traveling wave first point time, a device sampling rate and a distance between two devices;

[0084] determining a fault point position according to the traveling wave wave head position, the traveling wave first point time, the device sampling rate and the distance between the two devices by the following formula:

[0085]

[0086] wherein dis is the fault point position, i.e., the distance between the fault point and the device collecting the traveling wave x, l0 is the distance between the two devices, atime is the first sampling point time of the traveling wave x, btime is the first sampling point time of the traveling wave y, a point is the wave head subscript of the traveling wave x, b point is the wave head subscript of the traveling wave y, afs is the sampling frequency of the traveling wave x, bfs is the sampling frequency of the traveling wave y, and v is the traveling wave velocity.

[0087] The embodiment obtains the traveling wave data of two traveling waves of the network, finds the subscript of the mutation maximum value of the two traveling wave sequences, calculates the traveling wave slope list according to the traveling wave data and the subscript of the mutation maximum value, finds the traveling wave wave head position according to the traveling wave slope list, and determines the fault point position according to the traveling wave wave head position, the traveling wave first point time, the device sampling rate and the distance between the two devices, thereby reducing the calculation amount and the calculation time, involving fewer variables, introducing less error, improving the accuracy of fault location, and improving the speed and efficiency of network fault location.

[0088] Based on the above hardware structure, the network fault location method embodiment of the application is proposed.

[0089] Reference Figure 2 , Figure 2 The flowchart of the first embodiment of the network fault location method of the application is shown.

[0090] In the first embodiment, the network fault location method comprises the following steps:

[0091] Step S10, obtaining traveling wave data of two traveling waves of the distribution network, and searching for the subscript of the maximum mutation value of the two traveling wave sequences.

[0092] It should be noted that the traveling wave data is the traveling wave data corresponding to the double-terminal of the distribution network of the transformer substation, and the subscript of the maximum mutation value of the two traveling wave sequences can be searched after the traveling wave data is obtained.

[0093] Step S20, calculating a traveling wave slope list according to the traveling wave data and the subscript of the maximum mutation value.

[0094] It can be understood that the traveling wave slope list can be calculated by the traveling wave data and the subscript of the maximum mutation value by using a corresponding calculation formula.

[0095] Correspondingly, the step S20 specifically includes the following steps:

[0096] The traveling wave slope list is calculated according to the traveling wave data and the subscript of the maximum mutation value by the following formula:

[0097] sx[i]=x[i+1]-x[i-1]

[0098] sy[i]=y[i+1]-y[i-1]

[0099] Wherein, sx is the slope list of the traveling wave x, sy is the slope list of the traveling wave y, x, y is the traveling wave data, the subscript of the maximum mutation value of the traveling wave x is xindex, the subscript of the maximum mutation value of the traveling wave y is yindex, the length of the list sx is xindex, and the length of the list sy is yindex.

[0100] It can be understood that the traveling wave slope list can be calculated by the above formula, the list length of the slope list sx of the traveling wave x is xindex, and the list length of the slope list sy of the traveling wave y is yindex.

[0101] Step S30, searching for a traveling wave head position according to the traveling wave slope list, and determining a fault point position according to the traveling wave head position, a first point time of the traveling wave, a device sampling rate, and a distance between two devices.

[0102] It should be understood that the traveling wave head position can be searched by the traveling wave slope list, and the corresponding fault point position can be determined by substituting the traveling wave head position, the first point time of the traveling wave, the device sampling rate, and the distance between two devices into a corresponding calculation formula.

[0103] The embodiment obtains the traveling wave data of two traveling waves of the distribution network, finds the subscript of the maximum mutation value of the two traveling wave sequences, calculates a traveling wave slope list according to the traveling wave data and the subscript of the maximum mutation value, finds the traveling wave head position according to the traveling wave slope list, and determines the fault point position according to the traveling wave head position, the first point time of the traveling wave, the device sampling rate and the distance between the two devices, so that the calculation amount and the calculation time are reduced, the variables involved are less, the error introduced is less, the accuracy of fault positioning is improved, and the speed and efficiency of distribution network fault positioning are improved.

[0104] Further, Figure 3 The flowchart of the second embodiment of the distribution network fault positioning method is shown in the figure. Figure 3 The second embodiment of the distribution network fault positioning method is proposed based on the first embodiment, and the step S30 specifically includes the following steps in the embodiment.

[0105] In step S31, all points on the traveling wave slope list are obtained by a preset list calculation formula to obtain a target list.

[0106] It should be noted that all points on the traveling wave slope list participate in the calculation of the preset list calculation formula, and the corresponding list can be obtained.

[0107] Further, the step S31 specifically includes the following steps:

[0108] The target list is obtained by the following preset list calculation formula:

[0109]

[0110] Wherein, T(i) is the target list, E1(i) is the expected value of the traveling wave from the starting point to the subscript i, E2(i) is the expected value of the traveling wave from the subscript i to the last point, sd1 is the standard deviation of the traveling wave from the starting point to the subscript i, sd2 is the standard deviation of the traveling wave from the subscript i to the last point, N1 is the data length of the traveling wave from the starting point to the subscript i, and N2 is the data length of the traveling wave from the subscript i to the last point.

[0111] It should be understood that E1(i), sd1 and N1 refer to the expected value, standard deviation and data length of the traveling wave w from the starting point to the subscript i; E2(i), sd2 and N2 refer to the expected value, standard deviation and data length of the traveling wave w from the subscript i to the last point. The above formula is more sensitive to the mutation point of the time sequence compared with the general list calculation method.

[0112] Step S32, obtaining the current mutation confidence sequence according to the target list and a preset mutation confidence sequence calculation formula.

[0113] It can be understood that the corresponding mutation confidence sequence can be obtained by substituting the target list into the preset mutation confidence sequence calculation formula.

[0114] Further, the step S32 specifically comprises the following steps:

[0115] According to the target list, the current mutation confidence sequence is obtained according to the following preset mutation confidence sequence calculation formula:

[0116]

[0117] Wherein, P(i) is the current mutation confidence sequence, T(i) is the target list, is an incomplete beta function, v=n-2, n is the sequence length, and σ and η are constants.

[0118] In a specific implementation, σ can be preferably set to 0.4, and η can be preferably set to η=4.19ln(n)-11.54, of course, it can also be set to other numerical values, for example: σ can be preferably set to 0.3, 0.5, 0.41, 0.45, etc., and η can also be set to other numerical values, and the embodiment does not limit this; the heuristic automatic segmentation finds the wave head, that is, the statistical value of t test is used to determine whether the row wave has a mutation point; if it exists, the row wave is divided into two parts with the mutation point as the dividing point, forming two sub-sequences, and then the mutation points of each sub-sequence are found, until the length of each sub-sequence does not meet the set value; the mutation point refers to the T value of each point in the sub-sequence calculated by the following formula (1), and the maximum value Tmax of the T value is selected to participate in the calculation of formula (2), if the obtained P(T max ) exceeds the set value P0, that is, P(T max )≥P0=0.92, then the maximum point is the mutation point of the sub-sequence.

[0119]

[0120]

[0121] Wherein, the parameters can be set to η=4.19ln(n)-11.54, σ=0.4, v=n-2, I x (a, b) is an incomplete beta function; E1(i), sd1, N1 refer to the expected value, standard deviation, and data length of the sub-sequence of the row wave w from the starting point to the subscript i; E2(i), sd2, N2 refer to the expected value, standard deviation, and data length of the sub-sequence of the row wave w from the subscript i to the last point.

[0122] But in the process of network positioning verification, it is found that the above formula is slightly poor in sensitivity to mutation point. Under the same point number n, ptmax increases with the increase of tmax. Therefore, the above formula is modified as follows. The modified formula is more sensitive to the mutation point of time sequence:

[0123]

[0124] In a specific implementation, when the traveling wave fluctuates, the average slope difference of the left and right sides of a point of the traveling wave also fluctuates, the mutation confidence of the point increases sharply, and the purpose of finding the wave head can be achieved by finding the point where the average value changes through a heuristic automatic segmentation algorithm. Accordingly, the average difference sequence z is:

[0125] z(i) = |wr(i) - wl(i)|

[0126] wherein wl(i) is the average value of the traveling wave w from the starting point to the subsequence with index i; wr(i) is the average value of the traveling wave w from the subsequence with index i to the last point. In the process of finding the traveling wave head, only the first mutation point is needed. Therefore, in each segmentation of the subsequence, only the sequence from the starting point to the segmentation point is needed, and the latter subsequence can not participate in the calculation. In this way, the calculation amount and calculation time can be reduced.

[0127] Step S33, comparing the current mutation confidence sequence with a preset mutation confidence sequence threshold, and determining the position of the traveling wave head according to the comparison result.

[0128] It should be understood that the current mutation confidence sequence can be compared with the preset mutation confidence sequence threshold to generate a comparison result, and then the position of the traveling wave head can be determined according to the comparison result.

[0129] Step S34, acquiring the first point time of the traveling wave, the device sampling rate and the distance between the two devices, and determining the fault point position according to the position of the traveling wave head, the first point time of the traveling wave, the device sampling rate and the distance between the two devices.

[0130] It can be understood that the first point time of the traveling wave, the device sampling rate and the distance between the two devices are acquired, and the fault point position of the network fault can be determined by substituting the position of the traveling wave head, the first point time of the traveling wave, the device sampling rate and the distance between the two devices into the corresponding calculation formula.

[0131] Further, the step S34 specifically includes the following steps:

[0132] acquiring the first point time of the traveling wave, the device sampling rate and the distance between the two devices;

[0133] According to the traveling wave head position, the first point time of the traveling wave, the device sampling rate and the distance between the two devices, a fault point position is determined by the following formula:

[0134]

[0135] Wherein, dis is the fault point position, that is, the distance between the fault point and the device collecting the traveling wave x, l0 is the distance between the two devices, atime is the first sampling point time of the traveling wave x, btime is the first sampling point time of the traveling wave y, apoint is the traveling wave x head subscript, bpoint is the traveling wave y head subscript, afs is the sampling frequency of the traveling wave x, bfs is the sampling frequency of the traveling wave y, and v is the traveling wave velocity.

[0136] It should be understood that the fault point position can be obtained by the two traveling wave head positions, the first point time of the traveling wave, the device sampling rate and the distance between the two devices by using the above formula,

[0137] In the embodiment, the target list is obtained by using the preset list calculation formula on all points in the traveling wave slope list, the current mutation confidence sequence is obtained according to the target list and the preset mutation confidence sequence calculation formula, the current mutation confidence sequence and the preset mutation confidence sequence threshold are compared, the traveling wave head position is determined according to the comparison result, the first point time of the traveling wave, the device sampling rate and the distance between the two devices are obtained, and the fault point position is determined according to the traveling wave head position, the first point time of the traveling wave, the device sampling rate and the distance between the two devices. The calculation amount and the calculation time can be reduced, the number of variables involved is small, the error introduced is small, the accuracy of fault positioning is improved, and the speed and efficiency of distribution network fault positioning are improved.

[0138] Further, Figure 4 The flowchart of the third embodiment of the distribution network fault positioning method of the application is shown in FIG. 8. Figure 4 The third embodiment of the distribution network fault positioning method of the application is proposed based on the second embodiment. In the embodiment, the step S33 specifically includes the following steps.

[0139] In step S331, the current mutation confidence sequence and the preset mutation confidence sequence threshold are compared to generate a comparison result.

[0140] It should be noted that the comparison between the current mutation confidence sequence and the preset mutation confidence sequence threshold is to determine whether the mutation confidence sequence exceeds the set value, and then the comparison result can be generated.

[0141] In step S332, when the comparison result is that the current mutation confidence sequence does not exceed the preset mutation confidence sequence threshold, the traveling wave head position is determined to be at the maximum value of the traveling wave mutation.

[0142] It can be understood that when the comparison result is that the current mutation confidence sequence does not exceed the preset mutation confidence sequence threshold, it can be determined that the position of the wave front is at the maximum value of the traveling wave mutation, for example, when the preset mutation confidence sequence threshold is 0.92, it is judged whether the value Px exceeds the set value P0=0.92, if not, the wave front of the traveling wave x is at the maximum value of the traveling wave amplitude.

[0143] Step S333, when the comparison result is that the current mutation confidence sequence exceeds the preset mutation confidence sequence threshold, it is determined whether the subscript of the mutation maximum value exceeds the preset data length.

[0144] It should be understood that when the comparison result is that the current mutation confidence sequence exceeds the preset mutation confidence sequence threshold, it can be determined that the point is one of the mutation points of the traveling wave, and it can be further determined whether the subscript of the mutation maximum value exceeds the preset data length.

[0145] Step S334, when the subscript of the mutation maximum value does not exceed the preset data length, the subsequence of the slope list from the starting point to the subscript xt is taken as the input calculation list, and the final subsequence length does not exceed the preset data length, so that the first breakthrough point is taken as the position of the traveling wave front.

[0146] It can be understood that when the subscript of the mutation maximum value does not exceed the preset data length, the subsequence of the slope list sx from the starting point to the subscript xt is taken as the input, and the corresponding list is obtained by the T(i) formula, and the final subsequence length does not exceed the set value, so that the first breakthrough point is taken as the position of the traveling wave front.

[0147] It should be understood that taking the preset data length of 50 as an example, it is judged whether xt exceeds the set length l=50, if not, the wave front subscript of the traveling wave x is xt, otherwise, it jumps to the next step, that is, the subsequence of the slope list sx from the starting point to the subscript xt is taken as the input, and the mutation maximum value step is continued to be obtained, and the final subsequence length does not exceed the set value l=50; the first mutation point apoint is taken as the wave front of the traveling wave x, and the wave front finding step of the traveling wave y is consistent with that of the traveling wave x, and the wave front position is bpoint.

[0148] The embodiment compares the current mutation confidence sequence with a preset mutation confidence sequence threshold, generates a comparison result, determines that the traveling wave front position is at a traveling wave mutation maximum value when the comparison result is that the current mutation confidence sequence does not exceed the preset mutation confidence sequence threshold, determines whether the subscript of the mutation maximum value exceeds a preset data length when the comparison result is that the current mutation confidence sequence exceeds the preset mutation confidence sequence threshold, takes a subsequence from a start point to a subscript at a wave front subscript as an input calculation list until a final subsequence length does not exceed the preset data length when the subscript of the mutation maximum value does not exceed the preset data length, and takes a first breakthrough point as the traveling wave front position, so that the calculation amount and the calculation time are reduced, the involved variables are few, the introduced error is small, the fault positioning accuracy is improved, and the speed and efficiency of the distribution network fault positioning are improved.

[0149] Correspondingly, the application further provides a distribution network fault positioning device.

[0150] Reference Figure 5 , Figure 5 The figure is a function module diagram of the first embodiment of the distribution network fault positioning device.

[0151] In the first embodiment of the distribution network fault positioning device, the distribution network fault positioning device comprises:

[0152] The data acquisition module 10 is configured to acquire traveling wave data of two traveling waves of a distribution network, and find a subscript of a mutation maximum value of the two traveling wave sequences.

[0153] The list calculation module 20 is configured to calculate a traveling wave slope list according to the traveling wave data and the subscript of the mutation maximum value.

[0154] The fault determination module 30 is configured to find a traveling wave front position according to the traveling wave slope list, and determine a fault point position according to the traveling wave front position, a first point time of the traveling wave, a device sampling rate and a distance between two devices.

[0155] The list calculation module 20 is further configured to calculate the traveling wave slope list according to the traveling wave data and the subscript of the mutation maximum value by the following formula:

[0156] sx[i]=x[i+1]-x[i-1]

[0157] sy[i]=y[i+1]-y[i-1]

[0158] Wherein, sx is a slope list of the traveling wave x, sy is a slope list of the traveling wave y, x, y is traveling wave data, the subscript of the maximum mutation of the traveling wave x is xindex, the subscript of the maximum mutation of the traveling wave y is yindex, the length of the list sx is xindex, and the length of the list sy is yindex.

[0159] The fault determination module 30 is further configured to obtain a target list by a preset list calculation formula on all points on the traveling wave slope list, obtain a current mutation confidence sequence according to the target list and a preset mutation confidence sequence calculation formula, compare the current mutation confidence sequence with a preset mutation confidence sequence threshold, determine a traveling wave front position according to a comparison result, obtain a first point time of the traveling wave, a device sampling rate and a distance between two devices, and determine a fault point position according to the traveling wave front position, the first point time of the traveling wave, the device sampling rate and the distance between two devices.

[0160] The fault determination module 30 is further configured to obtain a target list by a preset list calculation formula on all points on the traveling wave slope list.

[0161]

[0162] Wherein, T(i) is the target list, E1(i) is an expected value of a subsequence from a starting point to a subscript i of the traveling wave, E2(i) is an expected value of a subsequence from the subscript i to a last point of the traveling wave, sd1 is a standard deviation of the subsequence from the starting point to the subscript i of the traveling wave, sd2 is a standard deviation of the subsequence from the subscript i to the last point of the traveling wave, N1 is a data length of the subsequence from the starting point to the subscript i of the traveling wave, and N2 is a data length of the subsequence from the subscript i to the last point of the traveling wave.

[0163] The fault determination module 30 is further configured to obtain a current mutation confidence sequence according to a preset mutation confidence sequence calculation formula according to the target list.

[0164]

[0165] Wherein, P(i) is the current mutation confidence sequence, T(i) is the target list, is an incomplete beta function, v=n-2, n is a sequence length, and σ and η are constants.

[0166] The fault determination module 30 is further configured to compare the current mutation confidence sequence with a preset mutation confidence sequence threshold to generate a comparison result; when the comparison result is that the current mutation confidence sequence does not exceed the preset mutation confidence sequence threshold, determine that the traveling wave front position is at the maximum mutation value; when the comparison result is that the current mutation confidence sequence exceeds the preset mutation confidence sequence threshold, determine whether the subscript of the maximum mutation value exceeds a preset data length; when the subscript of the maximum mutation value does not exceed the preset data length, take a subsequence from a start point to a subscript at the wave front subscript as an input calculation list until a final subsequence length does not exceed the preset data length, and take a first breakthrough point as the traveling wave front position.

[0167] The fault determination module 30 is further configured to obtain a traveling wave first point time, a device sampling rate and a distance between two devices.

[0168] The fault point position is determined according to the traveling wave front position, the traveling wave first point time, the device sampling rate and the distance between two devices by the following formula:

[0169]

[0170] wherein dis is the fault point position, that is, the distance between the fault point and the device collecting the traveling wave x, l0 is the distance between two devices, atime is the first sampling point time of the traveling wave x, btime is the first sampling point time of the traveling wave y, apoint is the subscript of the traveling wave x wave front, bpoint is the subscript of the traveling wave y wave front, afs is the sampling frequency of the traveling wave x, bfs is the sampling frequency of the traveling wave y, and v is the traveling wave velocity.

[0171] The steps implemented by each functional module of the distribution network fault locating device can refer to each embodiment of the distribution network fault locating method of the application, and will not be described here again.

[0172] In addition, the embodiment of the application further provides a storage medium, and the storage medium stores a distribution network fault locating program.

[0173] Obtain traveling wave data of two traveling waves of a distribution network, and find a subscript of a maximum mutation value of the two traveling wave sequences;

[0174] Calculate a traveling wave slope list according to the traveling wave data and the subscript of the maximum mutation value;

[0175] Find a traveling wave front position according to the traveling wave slope list, and determine a fault point position according to the traveling wave front position, a traveling wave first point time, a device sampling rate and a distance between two devices.

[0176] Further, the power distribution network fault locating program, when executed by the processor, further implements the following operations:

[0177] A list of traveling wave slopes is calculated according to the traveling wave data and the subscript of the maximum of the abrupt change by the following formula:

[0178] sx[i] = x[i+1] - x[i-1]

[0179] sy[i] = y[i+1] - y[i-1]

[0180] wherein sx is the list of traveling wave x slopes, sy is the list of traveling wave y slopes, x, y is the traveling wave data, the subscript of the maximum of the abrupt change of traveling wave x is xindex, the subscript of the maximum of the abrupt change of traveling wave y is yindex, the length of the list sx is xindex, and the length of the list sy is yindex.

[0181] Further, the power distribution network fault locating program, when executed by the processor, further implements the following operations:

[0182] All points on the list of traveling wave slopes are obtained by a preset list calculation formula to obtain a target list;

[0183] A current abrupt change confidence sequence is calculated according to the target list and a preset abrupt change confidence sequence calculation formula;

[0184] The current abrupt change confidence sequence is compared with a preset abrupt change confidence sequence threshold value, and a traveling wave front position is determined according to a comparison result;

[0185] A first point time of the traveling wave, a device sampling rate, and a distance between two devices are obtained, and a fault point position is determined according to the traveling wave front position, the first point time of the traveling wave, the device sampling rate, and the distance between the two devices.

[0186] Further, the power distribution network fault locating program, when executed by the processor, further implements the following operations:

[0187] All points on the list of traveling wave slopes are obtained by a preset list calculation formula to obtain a target list;

[0188]

[0189] wherein T(i) is the target list, E1(i) is an expected value of a subsequence of the traveling wave from a starting point to a subscript i, E2(i) is an expected value of a subsequence of the traveling wave from the subscript i to a last point, sd1 is a standard deviation of the subsequence of the traveling wave from the starting point to the subscript i, sd2 is a standard deviation of the subsequence of the traveling wave from the subscript i to the last point, N1 is a data length of the subsequence of the traveling wave from the starting point to the subscript i, and N2 is a data length of the subsequence of the traveling wave from the subscript i to the last point.

[0190] Further, the power distribution network fault locating program further implements the following operations when executed by the processor:

[0191] According to the target list, a current mutation confidence sequence is obtained according to a preset mutation confidence sequence calculation formula:

[0192]

[0193] Wherein, P(i) is the current mutation confidence sequence, T(i) is the target list, is an incomplete beta function, v=n-2, n is the sequence length, and σ and η are constants.

[0194] Further, the power distribution network fault locating program further implements the following operations when executed by the processor:

[0195] The current mutation confidence sequence and a preset mutation confidence sequence threshold are compared to generate a comparison result.

[0196] When the comparison result is that the current mutation confidence sequence does not exceed the preset mutation confidence sequence threshold, the traveling wave front position is determined to be at the maximum value of the traveling wave mutation.

[0197] When the comparison result is that the current mutation confidence sequence exceeds the preset mutation confidence sequence threshold, it is determined whether the subscript of the maximum value exceeds a preset data length.

[0198] When the subscript of the maximum value does not exceed the preset data length, a subsequence from the start point to the subscript of the wave head subscript is taken as an input calculation list until the final subsequence length does not exceed the preset data length, and the first breakthrough point is taken as the traveling wave front position.

[0199] Further, the power distribution network fault locating program further implements the following operations when executed by the processor:

[0200] The time of the first point of the traveling wave, the device sampling rate, and the distance between two devices are obtained.

[0201] According to the traveling wave front position, the time of the first point of the traveling wave, the device sampling rate, and the distance between two devices, the fault point position is determined by the following formula:

[0202]

[0203] Wherein, dis is the fault point position, that is, the distance between the fault point and the device collecting the traveling wave x, l0 is the distance between the two devices, atime is the first sampling point time of the traveling wave x, btime is the first sampling point time of the traveling wave y, apoint is the traveling wave x wave head subscript, bpoint is the traveling wave y wave head subscript, afs is the sampling frequency of the traveling wave x, bfs is the sampling frequency of the traveling wave y, and v is the traveling wave velocity.

[0204] The embodiment finds the subscript of the maximum mutation value of the two traveling wave sequences by acquiring the traveling wave data of the two traveling waves of the distribution network, calculates the traveling wave slope list according to the traveling wave data and the subscript of the maximum mutation value, finds the traveling wave head position according to the traveling wave slope list, and determines the fault point position according to the traveling wave head position, the first point time of the traveling wave, the device sampling rate and the distance between the two devices, so that the calculation amount and the calculation time are reduced, the involved variables are less, the introduced error is less, the accuracy of fault positioning is improved, and the speed and efficiency of distribution network fault positioning are improved.

[0205] It should be noted that in this document, the terms "comprise", "comprise", or any other variant thereof are intended to cover non-exclusive inclusion, so that processes, methods, articles or devices that include a series of elements not only include those elements, but also include other elements not explicitly listed, or include elements inherent to such processes, methods, articles or devices. Without more limitations, the element defined by the statement "comprises a" does not exclude the presence of additional identical elements in the process, method, article or device that includes the element.

[0206] The above-mentioned serial numbers of the embodiments of the application are only for description, and do not represent the advantages and disadvantages of the embodiments.

[0207] The above is only the preferred embodiment of the application, and does not limit the patent scope of the application. Any equivalent structure or equivalent process transformation, or direct or indirect application in other related technical fields, is also included in the patent protection scope of the application.

Claims

1. A network fault locating method, characterized in that, The power distribution network fault locating method comprises: Obtaining traveling wave data of two traveling waves of the power distribution network, and finding the subscript of the maximum mutation of the two traveling wave sequences; Calculating a traveling wave slope list according to the traveling wave data and the subscript of the maximum mutation; Finding a traveling wave head position according to the traveling wave slope list, and determining a fault point position according to the traveling wave head position, a first point time of the traveling wave, a device sampling rate, and a distance between two devices; The calculation of the traveling wave slope list according to the traveling wave data and the subscript of the maximum mutation comprises: The traveling wave slope list is calculated according to the traveling wave data and the subscript of the maximum mutation by the following formula: wherein, is a list of slopes of the running wave x, is a list of slopes of the running wave y, x, y are running wave data, the index of the maximum of the abrupt change of the running wave x is xindex, the index of the maximum of the abrupt change of the running wave y is yindex, the length of the list is xindex, the length of the list is yindex; The finding of the traveling wave head position according to the traveling wave slope list, and the determination of the fault point position according to the traveling wave head position, the first point time of the traveling wave, the device sampling rate, and the distance between two devices comprises: All points on the traveling wave slope list are obtained as a target list by a preset list calculation formula; A current mutation confidence sequence is obtained according to the target list and a preset mutation confidence sequence calculation formula; The current mutation confidence sequence is compared with a preset mutation confidence sequence threshold value, and the traveling wave head position is determined according to a comparison result; A first point time of the traveling wave, a device sampling rate, and a distance between two devices are obtained, and a fault point position is determined according to the traveling wave head position, the first point time of the traveling wave, the device sampling rate, and the distance between two devices; The obtaining of the target list by the preset list calculation formula comprises: The target list is obtained by the following preset list calculation formula: wherein, is a target list, is an expected value of the traveling wave from the start point to the sub-sequence with index i, is an expected value of the traveling wave from index i to the last point, is a standard deviation of the traveling wave from the start point to the sub-sequence with index i, is a standard deviation of the traveling wave from index i to the last point, is a data length of the traveling wave from the start point to the sub-sequence with index i, is a data length of the traveling wave from index i to the last point. The obtaining of the current mutation confidence sequence according to the target list and the preset mutation confidence sequence calculation formula comprises: The current mutation confidence sequence is obtained according to the target list and the following preset mutation confidence sequence calculation formula: wherein, is the current mutation confidence sequence, is the target list, is the incomplete beta function, n is the sequence length, and is a constant.

2. The network fault locating method of claim 1, wherein, The comparison of the current mutation confidence sequence with the preset mutation confidence sequence threshold value, and the determination of the traveling wave head position according to the comparison result comprises: The current mutation confidence sequence is compared with the preset mutation confidence sequence threshold value, and a comparison result is generated; When the comparison result is that the current mutation confidence sequence does not exceed the preset mutation confidence sequence threshold value, the traveling wave head position is determined to be at the maximum mutation of the traveling wave; When the comparison result is that the current mutation confidence sequence exceeds the preset mutation confidence sequence threshold value, it is determined whether the subscript of the maximum mutation exceeds a preset data length; When the subscript of the maximum mutation does not exceed the preset data length, a subsequence from a start point to the subscript of the traveling wave head is taken as an input calculation list until a final subsequence length does not exceed the preset data length, and a first breakthrough point is taken as the traveling wave head position.

3. The network fault locating method of claim 1, wherein, The obtaining of the first point time of the traveling wave, the device sampling rate, and the distance between two devices, and the determination of the fault point position according to the traveling wave head position, the first point time of the traveling wave, the device sampling rate, and the distance between two devices comprise: The first point time of the traveling wave, the device sampling rate, and the distance between two devices are obtained; According to the traveling wave head position, the first point time of the traveling wave, the device sampling rate and the distance between the two devices, a fault point position is determined by the following formula: wherein, is the fault point position, i.e. the distance of the fault point from the device collecting the travelling wave x, is the distance of the two devices, is the first sampling point time of the travelling wave x, is the first sampling point time of the travelling wave y, is the travelling wave x wave front index, is the travelling wave y wave front index, is the sampling frequency of the travelling wave x, is the sampling frequency of the travelling wave y, is the travelling wave wave speed.

4. A network fault locating device, characterized in that, The distribution network fault locating device comprises: A data acquisition module is configured to acquire traveling wave data of two traveling waves of a distribution network, and find subscripts of maximum mutations of the two traveling wave sequences. A list calculation module is configured to calculate a traveling wave slope list according to the traveling wave data and the subscripts of the maximum mutations. A fault determination module is configured to find a traveling wave head position according to the traveling wave slope list, and determine a fault point position according to the traveling wave head position, the first point time of the traveling wave, the device sampling rate and the distance between the two devices. The list calculation module is further configured to calculate the traveling wave slope list according to the traveling wave data and the subscripts of the maximum mutations by the following formula: wherein is a list of slopes of the running wave x, is a list of slopes of the running wave y, x, y are running wave data, the index of the maximum of the abrupt change of the running wave x is xindex, the index of the maximum of the abrupt change of the running wave y is yindex, the length of the list is xindex, the length of the list is yindex; The list calculation module is further configured to obtain a target list by a preset list calculation formula on all points of the traveling wave slope list, obtain a current mutation confidence sequence according to the target list and a preset mutation confidence sequence calculation formula, compare the current mutation confidence sequence with a preset mutation confidence sequence threshold, determine a traveling wave head position according to a comparison result, acquire a first point time of a traveling wave, a device sampling rate and a distance between two devices, and determine a fault point position according to the traveling wave head position, the first point time of the traveling wave, the device sampling rate and the distance between the two devices. The list calculation module is further configured to obtain a target list by the following preset list calculation formula on all points of the traveling wave slope list. wherein, is a target list, is an expected value of the traveling wave from the start point to the sub-sequence with index i, is an expected value of the traveling wave from index i to the last point, is a standard deviation of the traveling wave from the start point to the sub-sequence with index i, is a standard deviation of the traveling wave from index i to the last point, is a data length of the traveling wave from the start point to the sub-sequence with index i, is a data length of the traveling wave from index i to the last point The list calculation module is further configured to obtain a current mutation confidence sequence according to the target list and the following preset mutation confidence sequence calculation formula: wherein, is the current mutation confidence sequence, is the target list, is the incomplete beta function, n is the sequence length, and is a constant.

5. A network fault locating device, characterized by, The distribution network fault locating device comprises a memory, a processor and a distribution network fault locating program stored in the memory and executable on the processor, and the distribution network fault locating program is configured to implement steps of the distribution network fault locating method according to any one of claims 1 to 3.

6. A storage medium, characterized by The storage medium has a distribution network fault locating program stored thereon, and the distribution network fault locating program is executable on the processor to implement steps of the distribution network fault locating method according to any one of claims 1 to 3.

Images