Fault line detection method and device, equipment and medium

Abstract

The embodiment of the invention discloses a fault line detection method and device, equipment and a medium, and relates to the technical field of power distribution networks. The method comprises the following steps: acquiring zero-sequence current data of each feeder line in a three-phase circuit after a target time point; the target time point is the time when a feeder line in a three-phase circuit has a high-resistance grounding fault; the zero-sequence current data is time sequence data; constructing a zero-sequence current array corresponding to the feeder line based on the zero-sequence current data corresponding to the feeder line; and according to the zero-sequence current array corresponding to each feeder line, calculating the cosine similarity of the zero-sequence current between the feeder lines, and determining a fault feeder line in each feeder line based on the cosine similarity. According to the technical scheme, after the high-resistance grounding fault occurs in the three-phase circuit, the zero-sequence current array can be constructed based on the zero-sequence current data after the high-resistance grounding fault occurs, and the faulty feeder is accurately identified in each feeder according to the cosine similarity between the zero-sequence current arrays, so that support is provided for power utilization safety of a power distribution network.

Description

Technical Field

[0001] The present invention relates to the technical field of power distribution networks, and in particular to a method, device, equipment and medium for detecting a faulty line. Background Art

[0002] Single-phase grounding fault in distribution network is a very common fault type. When a single-phase grounding fault occurs, the commonly used line relay protection device relies on zero-sequence voltage and current to perform related operations such as protection start and tripping. However, if a high-resistance grounding fault occurs, the conventional line relay protection device can only start, but cannot trip reliably. This is because the zero-sequence voltage and current generated by the high-resistance grounding fault is very weak, whether it is arc suppression coil grounding or low-resistance grounding, resulting in the calculated judgment value being smaller than the set value and unable to operate reliably.

[0003] If the line relay device does not respond after a high-resistance grounding fault occurs, the distribution network operation and maintenance personnel will not be able to know which specific line has failed, and will not be able to quickly remove the fault through manual operation, affecting the safety of the distribution network. Therefore, after a high-resistance grounding fault occurs, how to accurately and quickly identify the line where the high-resistance grounding fault occurs is a technical problem that needs to be solved urgently. Summary of the invention

[0004] The present invention provides a fault line detection method, device, equipment and medium, which can accurately identify the fault line where a high-resistance grounding fault occurs after a high-resistance grounding fault occurs in a three-phase circuit.

[0005] According to one aspect of the present invention, a method for detecting a faulty line is provided, the method comprising:

[0006] Obtain zero-sequence current data of each feeder in the three-phase circuit after a target time point; the target time point is the time when a high-resistance grounding fault occurs in the feeder in the three-phase circuit; the zero-sequence current data is time series data;

[0007] Based on the zero-sequence current data corresponding to the feeder, a zero-sequence current array corresponding to the feeder is constructed;

[0008] According to the zero-sequence current array corresponding to each feeder, the cosine similarity of the zero-sequence currents between the feeders is calculated, and the faulty feeder is determined among the feeders based on the cosine similarity.

[0009] According to another aspect of the present invention, there is provided a fault line detection device, comprising:

[0010] A zero-sequence current data acquisition module is used to acquire zero-sequence current data of each feeder in the three-phase circuit after a target time point; the target time point is the time when a high-resistance grounding fault occurs in the feeder in the three-phase circuit; the zero-sequence current data is time series data;

[0011] A zero-sequence current array determination module is used to construct a zero-sequence current array corresponding to the feeder based on the zero-sequence current data corresponding to the feeder;

[0012] The fault feeder determination module is used to calculate the cosine similarity of the zero-sequence currents between feeders according to the zero-sequence current array corresponding to each feeder, and determine the faulty feeder among the feeders based on the cosine similarity.

[0013] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0014] at least one processor; and

[0015] a memory communicatively connected to the at least one processor; wherein,

[0016] The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the method for detecting a faulty line described in any embodiment of the present invention.

[0017] According to another aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the method for detecting a faulty line according to any embodiment of the present invention when executed.

[0018] The technical solution of the embodiment of the present application includes: obtaining the zero-sequence current data of each feeder in the three-phase circuit after the target time point; the target time point is the time when the high-resistance grounding fault occurs in the feeder in the three-phase circuit; the zero-sequence current data is time series data; based on the zero-sequence current data corresponding to the feeder, construct the zero-sequence current array corresponding to the feeder; according to the zero-sequence current array corresponding to each feeder, calculate the cosine similarity of the zero-sequence current between the feeders, and determine the faulty feeder in each feeder based on the cosine similarity. This technical solution can construct a zero-sequence current array based on the zero-sequence current data after the high-resistance grounding fault occurs in the three-phase circuit, and accurately identify the faulty feeder in each feeder based on the cosine similarity between the zero-sequence current arrays, providing support for the power safety of the distribution network.

[0019] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 is a flow chart of a fault line detection method provided according to Embodiment 1 of the present application;

[0022] Figure 2 This is a schematic diagram of a 10kV arc suppression coil grounding distribution network model provided according to Example 1 of the present application;

[0023] Figure 3 is a flow chart of a fault line detection method provided according to Embodiment 2 of the present application;

[0024] Figure 4 It is a structural schematic diagram of a fault line detection device provided according to Embodiment 3 of the present application;

[0025] Figure 5 It is a structural schematic diagram of an electronic device for implementing a method for detecting a faulty line according to an embodiment of the present application. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only embodiments of a part of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0027] It should be noted that the terms "first", "second", "target", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0028] Embodiment 1

[0029] Figure 1 A flow chart of a method for detecting a faulty line is provided for the first embodiment of the present application. The embodiment of the present application can be applied to identifying the faulty line when a high-resistance grounding fault occurs in a distribution network. The method can be performed by a detection device for a faulty line. The detection device for a faulty line can be implemented in the form of hardware and / or software. The detection device for a faulty line can be configured in an electronic device with data processing capabilities. Figure 1 As shown, the method includes:

[0030] S110, obtaining zero-sequence current data of each feeder in the three-phase circuit after a target time point.

[0031] Among them, the three-phase circuit is a common circuit system in the distribution network. In the three-phase circuit, it usually includes a busbar and a feeder. The number of feeders can be three, five, etc. Under normal circumstances, a high-resistance grounding fault in a three-phase circuit means that a certain feeder has a high-resistance grounding fault. The technical solution of the embodiment of the present application can identify the faulty feeder with a high-resistance grounding fault among the feeders. For example, Figure 2 This is a schematic diagram of a 10kV arc suppression coil grounded distribution network model. The distribution network is a specific example of a three-phase circuit, in which there are five feeders, and a high-resistance grounding fault occurs in feeder 4.

[0032] In an embodiment of the present application, the target time point is the time when a high-resistance grounding fault occurs in a feeder in a three-phase circuit, and the target time point can be determined based on the change in the zero-sequence voltage in the three-phase circuit. The zero-sequence current data is time-series data. For example, the collection period of the zero-sequence current is 0.02 seconds, and each period is collected 100 times, so one second of zero-sequence current data may include 5000 zero-sequence current values. A zero-sequence transformer is provided on each feeder, and the zero-sequence transformer can send the collected zero-sequence current to a recording device. The recording device has a recording function, and the zero-sequence current data before the current moment can be obtained through the recording device.

[0033] Specifically, the three-phase circuit can be continuously tested for high-resistance grounding faults. If a high-resistance grounding fault is determined to have occurred, the zero-sequence voltage data of the three-phase circuit over a period of time is obtained, and the specific time point when the high-resistance grounding fault occurs is determined based on the zero-sequence voltage, that is, the target time point, and the zero-sequence current data of each feeder after the target time point is obtained to determine the faulty feeder where the high-resistance grounding fault has occurred based on the zero-sequence current data.

[0034] In the embodiment of the present application, the zero-sequence mutual inductor, i.e., the current mutual inductor, is usually arranged at the head end of each feeder. Therefore, for the non-fault feeder, the zero-sequence current flows from the busbar to the line-to-ground capacitance, while the zero-sequence current of the faulty feeder is obtained by superposition of the grounding point and the line distributed capacitance flowing to the busbar. Therefore, the zero-sequence current detected at the head end of the faulty feeder flows through the inductance and capacitance, so it shows oscillation attenuation after the fault, and the transient process is longer, while the zero-sequence current transient process of the non-faulty feeder is only related to the capacitance, and the transient process is shorter. The faulty feeder can be identified by this feature.

[0035] S120, constructing a zero-sequence current array corresponding to the feeder based on the zero-sequence current data corresponding to the feeder.

[0036] Specifically, after obtaining the zero-sequence current data corresponding to the feeder, since the zero-sequence current data is time series data, it includes multiple zero-sequence current values. The zero-sequence current values ​​within a period of time can be superimposed, and the superposition result can be used as the value in the zero-sequence current array, so that when the cosine similarity is subsequently calculated, it can be calculated based on more zero-sequence current data to avoid unexpected interference.

[0037] S130, calculating the cosine similarity of the zero-sequence currents between the feeders according to the zero-sequence current array corresponding to each feeder, and determining the faulty feeder among the feeders based on the cosine similarity.

[0038] Specifically, every two feeders correspond to a cosine similarity. If neither of the two feeders has a high-resistance grounding fault, their zero-sequence currents are relatively similar, and the calculated cosine similarity is close to 1, such as 0.8, 0.7, etc. If a high-resistance grounding fault occurs in one of the two feeders, the zero-sequence currents of the two feeders have no similarity, and the calculated cosine similarity is close to 0. Accordingly, the faulty feeder can be identified in each feeder according to the cosine similarity corresponding to each feeder, so that the faulty feeder information can be sent to the receiving device, so that the faulty feeder can be processed in time.

[0039] The technical solution of the embodiment of the present application includes: obtaining the zero-sequence current data of each feeder in the three-phase circuit after the target time point; the target time point is the time when the high-resistance grounding fault occurs in the feeder in the three-phase circuit; the zero-sequence current data is time series data; based on the zero-sequence current data corresponding to the feeder, construct the zero-sequence current array corresponding to the feeder; according to the zero-sequence current array corresponding to each feeder, calculate the cosine similarity of the zero-sequence current between the feeders, and determine the faulty feeder in each feeder based on the cosine similarity. This technical solution can construct a zero-sequence current array based on the zero-sequence current data after the high-resistance grounding fault occurs in the three-phase circuit, and accurately identify the faulty feeder in each feeder based on the cosine similarity between the zero-sequence current arrays, providing support for the power safety of the distribution network.

[0040] Embodiment 2

[0041] Figure 3 This is a flow chart of a method for detecting a faulty line provided in Embodiment 2 of the present application. Embodiment 2 of the present application is optimized based on the above embodiment.

[0042] like Figure 3 As shown, the method of the embodiment of the present application specifically includes the following steps:

[0043] S210, continuously acquiring the real-time zero-sequence voltage of the three-phase circuit.

[0044] Specifically, since the high-resistance grounding fault in the three-phase circuit occurs randomly, the three-phase circuit can be monitored in real time. Specifically, the real-time zero-sequence voltage of the three-phase circuit can be continuously obtained, and the real-time zero-sequence voltage can be processed through subsequent steps to timely identify the faulty feeder after the high-resistance grounding fault occurs.

[0045] S220: If the real-time zero-sequence voltage is greater than the zero-sequence voltage limit value, then acquiring zero-sequence voltage data within a target time period.

[0046] Among them, the zero-sequence voltage data is time series data; the length of the target time period can be determined according to actual conditions, and the embodiment of the present application does not limit this. The target time period includes the time point when the real-time zero-sequence voltage is greater than the zero-sequence voltage limit value. For example, the target time period is from 8:01:01 to 8:01:02, and the time point when the real-time zero-sequence voltage is greater than the zero-sequence voltage limit value is after 8:01:01 and before 8:01:02.

[0047] Specifically, if the real-time zero-sequence voltage satisfies the following formula, the target time period is determined:

[0048] u0>u set ;

[0049] Among them, u0 is the real-time zero-sequence voltage, u set It is the zero-sequence voltage limit value.

[0050] When determining the target time period, the first time period before the time point when the real-time zero-sequence voltage is greater than the zero-sequence voltage limit value and the second time period after the time point can be determined as the target time period. For example, the first time period can be 0.5 seconds and the second time period can be 0.5 seconds.

[0051] This scheme is configured so that after determining that a high-resistance ground fault has occurred, a target time period is determined for the specific time when the high-resistance ground fault may have occurred, so as to determine a more specific target time point for the occurrence of the high-resistance ground fault based on zero-sequence voltage data within the target time period.

[0052] S230: In the zero-sequence voltage data, a sampling time point of a zero-sequence voltage value that satisfies a zero-sequence voltage jump condition is determined as a target time point.

[0053] Specifically, in the zero-sequence voltage data, since the three-phase circuit is affected by a high-resistance grounding fault, the zero-sequence voltage value will jump. The zero-sequence voltage values ​​in the zero-sequence voltage data can be traversed, and the sampling time point of the zero-sequence voltage value that meets the zero-sequence voltage jump condition is determined as the target time point.

[0054] In an embodiment of the present application, optionally, in the zero-sequence voltage data, a sampling time point of a zero-sequence voltage value that satisfies the zero-sequence voltage jump condition is determined as a target time point, including: traversing the zero-sequence voltage values ​​in the zero-sequence voltage data, if the current zero-sequence voltage value is greater than the sum of the zero-sequence voltage values ​​sampled within a preset time period, then determining the sampling time point of the current zero-sequence voltage value as the target time point, and ending the traversal; the sampling time of the current voltage value is after the preset time period.

[0055] Specifically, since there is a sampling cycle for the sampling of zero-sequence voltage (for example, 0.02 seconds is one cycle), the number of zero-sequence voltage values ​​within a sampling cycle can be calculated, and whether the current zero-sequence voltage value meets the zero-sequence voltage jump condition can be judged based on the zero-sequence voltage value within 1 / 4 cycle before the current zero-sequence voltage value.

[0056] Exemplarily, the duration corresponding to 1 / 4 of the sampling period before the current zero-sequence voltage value is determined as the reference time period, and the reference time period is evenly divided into two parts from the middle, namely, a preset time period and an interval time period, the preset time period is before the interval time period, and the interval time period is before the sampling time of the current zero-sequence voltage value. When traversing the zero-sequence voltage value, if the current zero-sequence voltage value is greater than the sum of the zero-sequence voltage values ​​sampled within the preset time period, the sampling time point of the current zero-sequence voltage value is determined as the target time point.

[0057] This arrangement of the present scheme can avoid the influence caused by periodic sampling, and can accurately identify the zero-sequence voltage values ​​that meet the zero-sequence voltage mutation condition among the zero-sequence voltage values, thereby making the determined target time point more accurate.

[0058] S240, obtaining zero-sequence current data of each feeder in the three-phase circuit after the target time point.

[0059] S250: construct a zero-sequence current array corresponding to the feeder based on the zero-sequence current data corresponding to the feeder.

[0060] In an embodiment of the present application, optionally, based on the zero-sequence current data corresponding to the feeder, a zero-sequence current array corresponding to the feeder is constructed, including: obtaining the number of samples for the zero-sequence current within a sampling period; traversing the zero-sequence current values ​​in the zero-sequence current data corresponding to the feeder, starting from the current zero-sequence current value, and obtaining the counted zero-sequence current value after the counted number reaches the sampling number; determining the non-periodic component of the zero-sequence current according to the counted zero-sequence current value; if it is determined that the number of non-periodic components reaches a preset threshold, the traversal is terminated, and the zero-sequence current array corresponding to the feeder is constructed according to the obtained non-periodic components.

[0061] Exemplarily, the number of samples may be 100. In the zero-sequence current data corresponding to the feeder, traversal is started from the first zero-sequence current value, and during traversal, counting is started from the current zero-sequence current value until the counted number reaches 100 and the counted zero-sequence current value is obtained; the non-periodic component of the zero-sequence current is determined according to the counted zero-sequence current value, and each non-periodic component can be used as a value in the zero-sequence current array. If the zero-sequence current array includes 10 values, the traversal is terminated after 10 non-periodic components are obtained.

[0062] In an embodiment of the present application, optionally, determining the non-periodic component of the zero-sequence current based on the counted zero-sequence current value includes: accumulating and summing the counted zero-sequence current values ​​to obtain a superposition result; and determining the absolute value of the superposition result as the non-periodic component of the zero-sequence current.

[0063] Exemplarily, the non-periodic component is determined according to the following formula:

[0064]

[0065] Among them, I tp_j is the non-periodic component, is the zero-sequence current value with serial number j+k, and j is the serial number corresponding to the current zero-sequence current value.

[0066] Furthermore, the zero-sequence current array is determined according to the following formula:

[0067]

[0068] in, is the zero-sequence current array, I tp_j ,I tp_j+1 etc. are all non-periodic components.

[0069] It should be noted that since the zero-sequence current value may be affected by the sampling period during sampling, the embodiment of the present application superimposes the zero-sequence current values ​​within a period to obtain a non-periodic component, thereby avoiding the influence of the sampling period on the zero-sequence current value, so that the calculation of subsequent results can be more accurate.

[0070] S260, calculating the cosine similarity of the zero-sequence currents between the feeders according to the zero-sequence current array corresponding to each feeder, and determining the faulty feeder among the feeders based on the cosine similarity.

[0071] In an embodiment of the present application, optionally, according to the zero-sequence current array corresponding to each feeder, the cosine similarity of the zero-sequence current between the feeders is calculated, including: normalizing the values ​​in the zero-sequence current array to obtain a normalized zero-sequence current array; performing the following operation on the normalized zero-sequence current arrays of the two feeders to obtain the cosine similarity:

[0072]

[0073] Among them, cosθ 1,2 is the cosine similarity between feeder 1 and feeder 2, is the normalized zero-sequence current array of feeder 1, is the normalized zero-sequence current array of feeder 2, and j is the jth value in the normalized zero-sequence current array.

[0074] Specifically, the values ​​in the zero-sequence current array are normalized according to the following formula:

[0075]

[0076] Among them, I' tp_j is the normalized non-periodic component, I tp_min is the minimum value in the zero-sequence current array, I tp_max is the maximum value in the zero-sequence current array, I tp_j is the non-periodic component.

[0077] In an embodiment of the present application, optionally, determining a faulty feeder among the feeders based on cosine similarity includes: traversing each feeder, respectively determining the cosine similarities between the currently traversed feeder and other feeders, and adding them to obtain a total cosine similarity corresponding to the currently traversed feeder; the other feeders are any feeders in the three-phase circuit except the currently traversed feeder; among the total cosine similarities corresponding to the feeders, determining the feeder with the smallest total cosine similarity as the faulty feeder.

[0078] For example, a cosine similarity can be calculated for every two feeders. For example, the cosine similarity between feeder 1 and feeder 2 is cosθ 1,2 , the cosine similarity between feeder 1 and feeder 4 is cosθ 1,4 …

[0079] If the number of feeders is 5, the cosine similarity corresponding to feeder 1 is determined according to the following formula:

[0080] cos1=cosθ 1,2+cosθ 1,3 +cosθ 1,4 +cosθ 1,5 ;

[0081] Among them, cos1 is the total cosine similarity corresponding to feeder 1, cosθ 1,2 is the cosine similarity between feeder 1 and feeder 2, cosθ 1,3 is the cosine similarity between feeder 1 and feeder 3, cosθ 1,4 is the cosine similarity between feeder 1 and feeder 4, cosθ 1,5 is the cosine similarity between feeder 1 and feeder 5.

[0082] Furthermore, among the total cosine similarities corresponding to the feeders, the feeder with the smallest total cosine similarity is determined as the faulty feeder.

[0083] For example, Table 1 is a schematic table of the results of line selection for a single-phase high-resistance ground fault. In Table 1, each value is the total cosine similarity. It can be seen that if the total cosine similarity corresponding to each feeder is the first row, the faulty feeder is feeder 1. If the total cosine similarity corresponding to each feeder is the second row, the faulty feeder is feeder 2...

[0084] Table 1 Schematic diagram of line selection results for single-phase high-resistance grounding fault

[0085]

[0086] The technical solution of the embodiment of the present application accurately determines the target time point of the occurrence of a high-resistance grounding fault through zero-sequence voltage data, and then obtains the zero-sequence current data of each feeder after the high-resistance grounding fault occurs, constructs a zero-sequence current array from the zero-sequence current data, and then accurately identifies the faulty feeder among the feeders based on the cosine similarity between the arrays, providing strong support for the power safety of the distribution network.

[0087] Embodiment 3

[0088] Figure 4 This is a schematic diagram of the structure of a fault line detection device provided in the third embodiment of the present application. The device can execute the fault line detection method provided in any embodiment of the present invention and has the corresponding functional modules and beneficial effects of the execution method. Figure 4 As shown, the device comprises:

[0089] The zero-sequence current data acquisition module 310 is used to acquire the zero-sequence current data of each feeder in the three-phase circuit after a target time point; the target time point is the time when a high-resistance grounding fault occurs in the feeder in the three-phase circuit; the zero-sequence current data is time series data;

[0090] A zero-sequence current array determination module 320 is used to construct a zero-sequence current array corresponding to the feeder based on the zero-sequence current data corresponding to the feeder;

[0091] The fault feeder determination module 330 is used to calculate the cosine similarity of the zero-sequence currents between feeders according to the zero-sequence current array corresponding to each feeder, and determine the faulty feeder among the feeders based on the cosine similarity.

[0092] The technical solution of the embodiment of the present application includes: a zero-sequence current data acquisition module 310, which is used to acquire the zero-sequence current data of each feeder in the three-phase circuit after the target time point; the target time point is the time when the high-resistance grounding fault occurs in the feeder in the three-phase circuit; the zero-sequence current data is time series data; a zero-sequence current array determination module 320, which is used to construct the zero-sequence current array corresponding to the feeder based on the zero-sequence current data corresponding to the feeder; a fault feeder determination module 330, which is used to calculate the cosine similarity of the zero-sequence current between the feeders according to the zero-sequence current array corresponding to each feeder, and determine the faulty feeder in each feeder based on the cosine similarity. This technical solution can construct a zero-sequence current array based on the zero-sequence current data after the high-resistance grounding fault occurs in the three-phase circuit, and accurately identify the faulty feeder in each feeder based on the cosine similarity between the zero-sequence current arrays, providing support for the power safety of the distribution network.

[0093] In the embodiment of the present application, optionally, the zero-sequence current array determination module 320 includes:

[0094] A sampling quantity determination unit, used for obtaining the sampling quantity of the zero-sequence current within a sampling period;

[0095] A counting unit, used for traversing the zero-sequence current values ​​in the zero-sequence current data corresponding to the feeder, starting from the current zero-sequence current value, and obtaining the counted zero-sequence current value after the counted number reaches the sampling number;

[0096] A non-periodic component determination unit, used for determining the non-periodic component of the zero-sequence current according to the counted zero-sequence current value;

[0097] The zero-sequence current array determination unit is used to terminate the traversal if it is determined that the number of non-periodic components reaches a preset threshold, and to construct a zero-sequence current array corresponding to the feeder according to the obtained non-periodic components.

[0098] In the embodiment of the present application, optionally, the non-periodic component determining unit includes:

[0099] The zero-sequence current value superposition subunit is used to accumulate and sum the counted zero-sequence current values ​​to obtain a superposition result;

[0100] The non-periodic component determination subunit is used to determine the absolute value of the superposition result as the non-periodic component of the zero-sequence current.

[0101] In the embodiment of the present application, optionally, the fault feeder determining module 330 includes:

[0102] A normalization unit, used for normalizing the values ​​in the zero-sequence current array to obtain a normalized zero-sequence current array;

[0103] The cosine similarity determination unit is used to perform the following operation on the normalized zero-sequence current arrays of the two feeders to obtain the cosine similarity:

[0104]

[0105] Among them, cosθ 1,2 is the cosine similarity between feeder 1 and feeder 2, is the normalized zero-sequence current array of feeder 1, is the normalized zero-sequence current array of feeder 2, and j is the jth value in the normalized zero-sequence current array.

[0106] In the embodiment of the present application, optionally, the fault feeder determining module 330 includes:

[0107] A feeder traversal unit, used to traverse each feeder, respectively determine the cosine similarity between the currently traversed feeder and other feeders, and add them to obtain a total cosine similarity corresponding to the currently traversed feeder; the other feeder is any feeder in the three-phase circuit except the currently traversed feeder;

[0108] The fault feeder determination unit is used to determine the feeder with the smallest total cosine similarity as the fault feeder among the total cosine similarities corresponding to the feeders.

[0109] In the embodiment of the present application, optionally, the device further includes: a target time point determination module, including:

[0110] A real-time zero-sequence voltage acquisition unit, used for continuously acquiring the real-time zero-sequence voltage of the three-phase circuit;

[0111] A zero-sequence voltage data acquisition unit, used for acquiring zero-sequence voltage data within a target time period if the real-time zero-sequence voltage is greater than the zero-sequence voltage limit value; the target time period includes a time point when the real-time zero-sequence voltage is greater than the zero-sequence voltage limit value; the zero-sequence voltage data is time series data;

[0112] The target time point determination unit is used to determine the sampling time point of the zero-sequence voltage value that meets the zero-sequence voltage jump condition in the zero-sequence voltage data as the target time point.

[0113] In the embodiment of the present application, optionally, the target time point determination unit includes:

[0114] The zero-sequence voltage value traversal subunit is used to traverse the zero-sequence voltage values ​​in the zero-sequence voltage data. If the current zero-sequence voltage value is greater than the sum of the zero-sequence voltage values ​​sampled within a preset time period, the sampling time point of the current zero-sequence voltage value is determined as the target time point and the traversal is ended; the sampling time of the current voltage value is after the preset time period.

[0115] A fault line detection device provided in an embodiment of the present application can execute a fault line detection method provided in any embodiment of the present invention, and has functional modules and beneficial effects corresponding to the execution method.

[0116] Embodiment 4

[0117] Figure 5 A schematic diagram of the structure of an electronic device 10 that can be used to implement an embodiment of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0118] like Figure 5 As shown, the electronic device 10 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0119] A number of components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0120] The processor 11 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as a method for detecting a faulty line.

[0121] In some embodiments, the method for detecting a faulty line may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the method for detecting a faulty line described above may be performed. Alternatively, in other embodiments, the processor 11 may be configured to execute the method for detecting a faulty line in any other appropriate manner (e.g., by means of firmware).

[0122] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), complex programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0123] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0124] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in combination with an instruction execution system, device or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0125] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0126] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0127] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0128] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0129] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for detecting a faulty line, characterized in that: include: Obtain zero-sequence current data of each feeder in the three-phase circuit after a target time point; The target time point is the time when a high-resistance grounding fault occurs in a feeder in a three-phase circuit; The zero-sequence current data is time series data; Based on the zero-sequence current data corresponding to the feeder, a zero-sequence current array corresponding to the feeder is constructed; According to the zero-sequence current array corresponding to each feeder, the cosine similarity of the zero-sequence currents between the feeders is calculated, and the faulty feeder is determined among the feeders based on the cosine similarity.

2. The method according to claim 1, characterized in that Based on the zero-sequence current data corresponding to the feeder, a zero-sequence current array corresponding to the feeder is constructed, including: Obtain the number of samples of zero-sequence current in a sampling period; The zero-sequence current values ​​in the zero-sequence current data corresponding to the feeder are traversed, and counting is started from the current zero-sequence current value until the counted number reaches the sampling number, and then the counted zero-sequence current value is obtained; determining a non-periodic component of the zero-sequence current according to the counted zero-sequence current value; If it is determined that the number of non-periodic components reaches a preset threshold, the traversal is terminated, and a zero-sequence current array corresponding to the feeder is constructed according to the obtained non-periodic components.

3. The method according to claim 2, characterized in that The non-periodic component of the zero-sequence current is determined according to the counted zero-sequence current value, including: The counted zero-sequence current values ​​are accumulated and summed to obtain a superposition result; The absolute value of the superposition result is determined as the non-periodic component of the zero-sequence current.

4. The method according to claim 1, characterized in that: According to the zero-sequence current array corresponding to each feeder, the cosine similarity of the zero-sequence current between feeders is calculated, including: Normalizing the values ​​in the zero-sequence current array to obtain a normalized zero-sequence current array; The normalized zero-sequence current arrays of the two feeders are operated as follows to obtain the cosine similarity: Among them, cosθ 1,2 is the cosine similarity between feeder 1 and feeder 2, is the normalized zero-sequence current array of feeder 1, is the normalized zero-sequence current array of feeder 2, and j is the jth value in the normalized zero-sequence current array.

5. The method according to claim 4, characterized in that The faulty feeder is determined among the feeders based on the cosine similarity, including: Traversing each feeder, respectively determining the cosine similarity between the currently traversed feeder and other feeders, and summing them up to obtain a total cosine similarity corresponding to the currently traversed feeder; the other feeder is any feeder in the three-phase circuit except the currently traversed feeder; Among the total cosine similarities corresponding to the feeders, the feeder with the smallest total cosine similarity is determined as the faulty feeder.

6. The method according to claim 1, characterized in that The process of determining the target time point includes: Continuously acquiring the real-time zero-sequence voltage of the three-phase circuit; If the real-time zero-sequence voltage is greater than the zero-sequence voltage limit value, the zero-sequence voltage data within the target time period is obtained; the target time period includes the time point when the real-time zero-sequence voltage is greater than the zero-sequence voltage limit value; the zero-sequence voltage data is time series data; In the zero-sequence voltage data, a sampling time point of a zero-sequence voltage value that meets a zero-sequence voltage jump condition is determined as a target time point.

7. The method according to claim 6, characterized in that In the zero-sequence voltage data, the sampling time point of the zero-sequence voltage value that meets the zero-sequence voltage jump condition is determined as the target time point, including: The zero-sequence voltage values ​​in the zero-sequence voltage data are traversed. If the current zero-sequence voltage value is greater than the sum of the zero-sequence voltage values ​​sampled within a preset time period, the sampling time point of the current zero-sequence voltage value is determined as the target time point, and the traversal is terminated; the sampling time of the current voltage value is after the preset time period.

8. A fault line detection device, characterized in that: include: A zero-sequence current data acquisition module is used to acquire zero-sequence current data of each feeder in the three-phase circuit after a target time point; The target time point is the time when a high-resistance grounding fault occurs in a feeder in a three-phase circuit; The zero-sequence current data is time series data; A zero-sequence current array determination module is used to construct a zero-sequence current array corresponding to the feeder based on the zero-sequence current data corresponding to the feeder; The fault feeder determination module is used to calculate the cosine similarity of the zero-sequence currents between feeders according to the zero-sequence current array corresponding to each feeder, and determine the faulty feeder among the feeders based on the cosine similarity.

9. An electronic device, characterized in that: The electronic device comprises: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can perform the method for detecting a faulty line according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the method for detecting a faulty line according to any one of claims 1 to 7 when the processor executes the instructions.

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