Power distribution network high-resistance grounding fault positioning method and system

Abstract

The invention discloses a power distribution network high-resistance grounding fault positioning method and system. The method comprises the following steps: acquiring a first parameter of a power distribution line in a target power distribution network; obtaining a first fault data set according to the first parameter in combination with a preset first fault positioning model; and performing first deviation value estimation according to the first fault data set, and performing fault positioning according to a first deviation value estimation result. A search is computed by generating a set of possible fault locations. According to the voltage and current of each fault point, an equivalent model of a downstream network of each fault point is established. And estimating fault current and arc parameters by using the equivalent model. An estimated fault phase voltage is then calculated on a source node where distribution network protection (IED) is installed using the estimated high-resistance ground fault parameters. And the deviation between the estimated voltage and the measured voltage is used as a basis for judging the position of the high-resistance grounding fault, and finally, fault positioning during the high-resistance grounding fault of the distribution line is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of high-resistance grounding fault locating in a distribution network, and in particular to a method and system for locating a high-resistance grounding fault in a distribution network. Background Art

[0002] When a high-resistance grounding fault occurs in the distribution network, the fault resistance is high and has nonlinear characteristics, resulting in a small fault current and nonlinear amplitude changes, making detection difficult.

[0003] In the case of a high-resistance ground fault, the ground current is small and may not be enough to generate enough current for the human body to escape, increasing the risk of electric shock. In addition, the fault may not immediately trigger the tripping protection of the circuit breaker, causing the fault to exist for a long time, which may cause thermal damage or insulation aging of electrical equipment and reduce the service life of the equipment. After the protection trips, quickly and accurately locating the fault section and fault location can effectively guide fault maintenance, reduce power outage time, and improve system power supply reliability. Summary of the invention

[0004] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0005] In view of the above existing problems, the present invention is proposed.

[0006] Therefore, the present invention provides a method and system for locating a high-resistance grounding fault in a distribution network, which can solve the problems mentioned in the background technology.

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] In a first aspect, the present invention provides a method for locating a high-resistance grounding fault in a distribution network, comprising:

[0009] Obtaining a first parameter of a distribution line in a target distribution network;

[0010] According to the first parameter and in combination with a preset first fault location model, a first fault data set is acquired;

[0011] A first deviation value is estimated according to the first fault data set, and fault location is performed according to the first deviation value estimation result.

[0012] As a preferred solution of the method for locating a high-resistance grounding fault in a distribution network according to the present invention, wherein: the obtaining of a first fault data set according to the first parameter and in combination with a preset first fault location model comprises:

[0013] The first fault location model is any model whose input is the first parameter and whose output is the fault point location or a parameter related to the fault point location;

[0014] The parameters related to the fault point location at least include several parameters related to the fault point location that can be obtained.

[0015] As a preferred solution of the method for locating a high-resistance grounding fault in a distribution network according to the present invention, wherein: the estimating a first deviation value according to the first fault data set comprises:

[0016] The first fault data set is a combination set output by the first fault location model, and the first fault data set includes a plurality of fault point locations;

[0017] The first deviation value is estimated according to the location sequence of the plurality of fault points in the first fault set.

[0018] As a preferred solution of the method for locating a high-resistance grounding fault in a distribution network according to the present invention, wherein: the estimating the first deviation value according to the first fault data set further comprises:

[0019] Establishing a first target inspection node set;

[0020] The first target inspection node set includes all nodes to be tested in the distribution lines of the target distribution network;

[0021] According to the sequence of the positions of the several fault points in the first fault set, the voltages of the subsequent nodes are calculated starting from the first node in the first target inspection node set along the fault path direction until the corresponding fault point position in the first fault set is reached.

[0022] As a preferred solution of the method for locating a high-resistance grounding fault in a distribution network according to the present invention, wherein: the estimating the first deviation value according to the first fault data set further comprises:

[0023] The voltages of subsequent nodes are calculated starting from the first node in the first target inspection node set along the fault path direction according to the location sequence of several fault points in the first fault set using one cycle data after the fault.

[0024] As a preferred solution of the method for locating a high-resistance grounding fault in a distribution network according to the present invention, wherein: the estimating the first deviation value according to the first fault data set further comprises:

[0025] According to the position sequence of several fault points in the first fault set, starting from the first node in the first target inspection node set, calculate the voltage of each subsequent node along the fault path direction until the corresponding fault point position in the first fault set, and record the voltage at this position as the first fault voltage;

[0026] Calculate the downstream equivalent parameter at the fault point according to the first fault voltage;

[0027] Acquire a high-resistance grounding fault parameter according to the downstream equivalent parameter;

[0028] The node voltage is calculated according to the high-resistance grounding fault parameter.

[0029] As a preferred solution of the method for locating a high-resistance grounding fault in a distribution network according to the present invention, the fault locating according to the first deviation value estimation result includes:

[0030] Calculating a first deviation value estimation result according to the node voltage calculated by the high-resistance grounding fault parameter and the actually measured node voltage;

[0031] And fault location is performed according to the first deviation value estimation result.

[0032] In a second aspect, the present invention provides a distribution network high-resistance grounding fault location system, comprising:

[0033] A data acquisition module, used to acquire a first parameter of a distribution line in a target distribution network;

[0034] A data set acquisition module, configured to acquire a first fault data set according to the first parameter and in combination with a preset first fault location model;

[0035] A positioning module is used to estimate a first deviation value according to the first fault data set, and to locate the fault according to the first deviation value estimation result.

[0036] In a third aspect, the present invention provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above-mentioned method when executing the computer program.

[0037] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of the method described above when executed by a processor.

[0038] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention proposes a method and system for locating a high-resistance grounding fault in a distribution network, obtaining a first parameter of a distribution line in a target distribution network; obtaining a first fault data set according to the first parameter in combination with a preset first fault location model; estimating a first deviation value according to the first fault data set, and locating the fault according to the first deviation value estimation result. The search is calculated by generating a set of possible fault locations. An equivalent model of the downstream network of each fault point is established according to the voltage and current of each fault point. The fault current and arc parameters are estimated using the equivalent model. Then, the estimated high-resistance grounding fault parameters are used to calculate the estimated fault phase voltage at the source node where the distribution network protection (IED) is installed. The deviation between the estimated voltage and the measured voltage is used as a basis for determining the location of the high-resistance grounding fault, and finally the fault location of the distribution line high-resistance grounding fault is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. 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 labor. Among them:

[0040] Figure 1 A method flow chart of a method and system for locating a high-resistance grounding fault in a distribution network provided by an embodiment of the present invention;

[0041] Figure 2 A schematic diagram of a high-resistance fault in a distribution line provided by a method and system for locating a high-resistance grounding fault in a distribution network according to an embodiment of the present invention;

[0042] Figure 3 A schematic diagram of an equivalent circuit of a line downstream of a distribution network high-resistance grounding fault location method and system provided by an embodiment of the present invention;

[0043] Figure 4 A detailed flow chart of a method and system for locating a high-resistance grounding fault in a distribution network provided by an embodiment of the present invention;

[0044] Figure 5 An internal structural diagram of a computer device of a method and system for locating a high-resistance grounding fault in a distribution network provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0046] Example 1

[0047] Reference Figure 1-Figure 5 , which is the first embodiment of the present invention, provides a method and system for locating a high-resistance grounding fault in a distribution network, including:

[0048] There are some deficiencies in the existing related technologies, such as low accuracy of fault location, slow fault detection speed, and difficulty in quickly locating fault points in complex distribution network structures.

[0049] The present application provides a method that can effectively solve the above-mentioned problems. Next, multiple embodiments will be combined to explain in detail how to implement the method for locating a high-resistance grounding fault in a distribution network.

[0050] Figure 1 A method flow chart of a method and system for locating a high-resistance grounding fault in a distribution network is shown, including:

[0051] S101, obtaining a first parameter of a distribution line in a target distribution network;

[0052] In an optional embodiment, the first parameter of the distribution line in the target distribution network may include electrical parameters such as voltage, current information, resistance, reactance, etc. in the distribution line. These parameters may be collected in real time or may be historical data pre-stored in the system. Acquiring these parameters is the basis for fault location because they can reflect the electrical characteristics of the distribution network in normal operation and fault state.

[0053] In an optional embodiment, the first parameter of the distribution line in the target distribution network can be obtained by a preset sensor, such as a current transformer and a voltage transformer. These sensors can be installed at key nodes of the distribution network to monitor and record changes in electrical parameters in real time. Through these sensors, the accuracy and real-time nature of the data can be ensured, providing reliable data support for fault location.

[0054] In an optional embodiment, the first parameter of the distribution line in the target distribution network can also be obtained by using a distribution terminal or other monitoring equipment installed on the distribution line, for example, a smart meter or a remote terminal unit (RTU) on the distribution line. These devices usually have data acquisition and communication functions, and can transmit the collected electrical parameters back to the control center via a wireless or wired network. These devices can be used to achieve remote monitoring and management of the distribution network, further improving the efficiency and accuracy of fault location.

[0055] In an optional embodiment, the first parameter of the distribution line in the target distribution network can also be obtained by other means, for example, by a historical data query function of a distribution network management system, or by data exchange with other systems connected to the distribution network, such as a SCADA (Supervisory Control and Data Acquisition System). These methods can provide additional reference information, which is helpful for a more comprehensive analysis of the operating status of the distribution network, thereby improving the accuracy of fault location.

[0056] In the embodiment of the present application, the voltage and current information on the distribution line is collected by using the distribution terminal or other monitoring equipment installed on the distribution line, and the data is sampled at 128 points per cycle, and sent to the distribution master station after collection;

[0057] It should be noted that obtaining the first parameter of the distribution line in the target distribution network can ensure the accuracy and timeliness of fault location. By real-time monitoring and recording the changes in electrical parameters, any abnormal situation occurring in the distribution network can be quickly responded to.

[0058] S102, acquiring a first fault data set according to the first parameter and in combination with a preset first fault location model;

[0059] In the embodiment of the present application, according to the first parameter and in combination with the preset first fault location model, obtaining the first fault data set includes:

[0060] The first fault location model is any model whose input is the first parameter and whose output is the fault point location or a parameter related to the fault point location;

[0061] The parameters related to the fault point location include at least a number of related parameters that can be used to obtain the fault point location.

[0062] In an optional embodiment, the first fault location model can use a physical model-based method, which uses the physical principles and mathematical models of the power system to construct a fault location model. It usually needs to consider the electrical parameters of the distribution line (such as resistance, reactance, etc.) and the voltage and current changes when the fault occurs. By simulating the electrical behavior when the fault occurs, the location of the fault point can be predicted. The advantage of this method is that it has a solid theoretical foundation, but the disadvantage is that it has high requirements for the accuracy of the model and may require a lot of prior knowledge.

[0063] In an optional embodiment, the first fault location model can also use an artificial intelligence-based method. With the development of machine learning and deep learning, more and more researchers have begun to explore the use of artificial intelligence technology to solve the problem of high-resistance grounding fault location in distribution networks. Such methods mainly include but are not limited to support vector machines (SVM), neural networks (NN), decision trees (DT), random forests (RF), etc. These models can learn fault modes from a large amount of historical data to predict fault points. Artificial intelligence-based methods have good adaptability and generalization capabilities, but require a large amount of labeled data during the training process, and the interpretability of the model may be poor.

[0064] In an optional embodiment, the first fault location model can also use a hybrid method: combining the advantages of physical models and artificial intelligence, a hybrid method is used to design the fault location model. For example, a physical model can be used to extract fault features first, and then a machine learning algorithm can be used to classify or regress these features to determine the location of the fault point. This approach retains the theoretical advantages of the physical model and utilizes the flexibility and efficiency of artificial intelligence.

[0065] In the embodiment of the present application, the first fault location model can use the existing high-resistance grounding fault detection algorithm to detect data. When a high-resistance grounding fault is detected, the fault initial time T is set to m and the fault phase are sent to the high-resistance fault location module;

[0066] In an optional embodiment, the parameters related to the location of the fault point may include voltage drop. The voltage near the fault point will drop significantly. By monitoring the voltage changes at different nodes, the approximate location of the fault can be preliminarily determined. For example, if the voltage of a certain section of the line drops suddenly, while the voltage of other sections of the line is normal, this may mean that the fault point is located near the section of the line where the voltage drops.

[0067] In an optional embodiment, the parameters related to the location of the fault point may also include a current change value. When a fault occurs, the current near the fault point will increase significantly. Especially in the case of a high-resistance grounding fault, although the current change amplitude is small, it can still be used to assist in positioning. For example, by monitoring the current changes of each node, it can be found that the current of a certain section of the line suddenly increases, which may indicate that the fault point is located near the section of the line.

[0068] In an optional embodiment, the parameters related to the location of the fault point may also include a fault resistance. One of the characteristics of a high-resistance grounding fault is that the fault resistance is relatively high. By measuring the resistance value of the fault point, the range of the fault point can be further narrowed. For example, if the fault resistance value of a certain section of the line is measured to be relatively high, this may mean that the fault point is located in the section of the line.

[0069] In an optional embodiment, the parameters related to the location of the fault point may also include a fault phase angle. When a fault occurs, the voltage and current phase angles near the fault point will change. By analyzing the change in the phase angle, the fault point can be located. For example, if the voltage and current phase angles of a certain section of the line change significantly, this may indicate that the fault point is located near the section of the line.

[0070] In an optional embodiment, the parameters related to the location of the fault point may also include harmonic components. When a fault occurs, the harmonic components in the system may change. By analyzing the harmonic components, the fault point can be assisted in locating. For example, if the harmonic components of a certain section of the line increase significantly, this may mean that the fault point is located near the section of the line.

[0071] In an optional embodiment, the parameters related to the fault point location may also include zero-sequence current. In a high-resistance ground fault, zero-sequence current is an important characteristic parameter. By monitoring the change of zero-sequence current, the fault point can be assisted in locating. For example, if the zero-sequence current of a certain section of the line increases significantly, this may indicate that the fault point is located near the section of the line.

[0072] In an optional embodiment, the parameters related to the location of the fault point may also include the change trend of the voltage and current after the fault occurs. By analyzing the change trend of the voltage and current after the fault occurs, the location of the fault point can be further refined. For example, if the voltage and current of a certain section of the line show a specific change trend after the fault, this may indicate that the fault point is located near the section of the line.

[0073] In an optional embodiment, the parameters related to the fault point location may also include equivalent parameters downstream of the fault point. By calculating the equivalent parameters downstream of the fault point location, the location of the fault point can be determined more accurately. For example, the specific location of the fault point can be calculated based on the parameters such as the downstream equivalent resistance and reactance at the fault point location.

[0074] In the embodiment of the present application, the parameters related to the fault point location are selected as equivalent parameters downstream of the fault point, because these parameters can provide direct information about the electrical characteristics downstream of the fault point.

[0075] It should be noted that the equivalent parameters downstream of the fault point include equivalent resistance, equivalent reactance, etc., which can reflect the electrical load conditions downstream of the fault point. By measuring these parameters, the location of the fault point can be determined more accurately. For example, if the equivalent resistance downstream of the fault point suddenly increases, this may indicate that the fault point is near the location where the resistance increases.

[0076] S103, estimating a first deviation value according to the first fault data set, and locating the fault according to the first deviation value estimation result.

[0077] In an embodiment of the present application, estimating a first deviation value according to a first fault data set includes:

[0078] The first fault data set is a combination set of outputs of the first fault location model, and the first fault data set includes a plurality of fault point locations;

[0079] The first deviation value is estimated according to the position sequence of the plurality of fault points in the first fault set.

[0080] In an optional embodiment, the first deviation value estimation can use different means to estimate the deviation value. For example, a statistical analysis method can be used to evaluate the deviation of the fault point location, or a machine learning algorithm can be used to predict the deviation value. The statistical analysis method may include calculating the mean, median or standard deviation of the fault point location, while the machine learning algorithm may involve regression analysis, cluster analysis and other techniques. These methods can help us estimate the deviation value more accurately, thereby improving the accuracy of fault location. In practical applications, the choice of which deviation value estimation method depends on the characteristics of the fault data and the required positioning accuracy. In addition, the results of the deviation value estimation can also be used to optimize the fault location model, and the model can be more adapted to the actual distribution network environment by continuously iterating and adjusting the model parameters.

[0081] In the embodiment of the present application, estimating the first deviation value according to the first fault data set further includes:

[0082] Establishing a first target inspection node set;

[0083] The first target inspection node set includes all nodes to be tested in the distribution lines of the target distribution network;

[0084] According to the position sequence of several fault points in the first fault set, the voltages of subsequent nodes are calculated starting from the first node in the first target inspection node set along the fault path direction until the corresponding fault point position in the first fault set is reached.

[0085] In the embodiment of the present application, estimating the first deviation value according to the first fault data set further includes:

[0086] The voltages of subsequent nodes are calculated starting from the first node in the first target inspection node set along the fault path direction according to the location sequence of several fault points in the first fault set using one cycle data after the fault.

[0087] In the embodiment of the present application, estimating the first deviation value according to the first fault data set further includes:

[0088] According to the position sequence of several fault points in the first fault set, the voltage of each subsequent node is calculated from the first node in the first target inspection node set along the fault path direction until the corresponding fault point position in the first fault set is reached, and the voltage at this position is recorded as the first fault voltage;

[0089] Calculate the downstream equivalent parameter at the fault point according to the first fault voltage;

[0090] Obtain high-resistance grounding fault parameters based on downstream equivalent parameters;

[0091] Calculate node voltage based on high-resistance ground fault parameters.

[0092] In the embodiment of the present application, locating the fault according to the first deviation value estimation result includes:

[0093] Calculating a first deviation value estimation result according to the node voltage calculated by the high-resistance grounding fault parameter and the actually measured node voltage;

[0094] And the fault location is performed according to the first deviation value estimation result.

[0095] In the embodiment of the present application, the voltage and current information on the distribution line is collected by using the distribution terminal or other monitoring equipment installed on the distribution line, and the data is sampled at 128 points per cycle, and sent to the distribution master station after collection;

[0096] Furthermore, after the distribution master station obtains the voltage and current information on the distribution line, it detects the data according to the existing high-resistance grounding fault detection algorithm. When a high-resistance grounding fault is detected, the fault initial time T is set. m and the fault phase are sent to the high-resistance fault location module;

[0097] Furthermore, the initial time of the high-resistance ground fault is T m , considering the delay at the initial time of high-resistance ground fault detection, {T m -30ms, T m -10ms} is the data before the fault. m , T m +20ms} one-cycle data is the post-fault data;

[0098] In an optional embodiment, the delay here can be designed according to actual needs and is not limited here.

[0099] Furthermore, on the fault phase line, according to its line length, a possible fault point location sequence set X = {x i}, i = 1…n. The fault point location can be set at 1km intervals or designed accordingly according to actual needs.

[0100] Furthermore, starting from the first possible fault point position in the set X, calculations are performed one by one.

[0101] Furthermore, using the data of one cycle after the fault, the voltage of each subsequent node is calculated along the fault path from the first node until the assumed fault point x i Position till;

[0102] from Figure 2 The voltage drop between nodes i and j in the distribution line is:

[0103]

[0104] The node voltage V i (t)=[V ai V bi V ci ] T , the node current I ij (t) = [I aij I bij I cij ] T ,

[0105] Line resistance Line inductance

[0106] The current relationship of node i is as follows:

[0107] I ij (t) = I (i-1)i (t)-I iLat (t)-I iC (t)-I iLoad (t) (2)

[0108] Among them I iLat (t) is the branch line current, I iC (t) is the current of the shunt capacitor at node i, I iLoad (t) is the load current of node i.

[0109] Based on formulas (1) and (2), we can calculate the voltage V of each subsequent node along the fault path starting from the first node. i (t).

[0110] Furthermore, using the cycle data before the fault, the assumed fault point x i Calculation of equivalent parameters downstream of the location;

[0111] Use the one-cycle data before the fault to calculate x according to the above method. i Voltage and current at

[0112] Taking advantage of the fact that the load changes very little in a short period of time during a high-resistance single-phase grounding fault, Figure 3 The equivalent circuit can be obtained as formula (3):

[0113]

[0114] where r LL 、r LM , l LL , l LM They are the self-resistance, mutual resistance, self-inductance and mutual inductance per unit length of the line. eq is the equivalent line length, R Load-a , L Load-a are the load equivalent resistance and inductance.

[0115] x i Voltage and current at It is known that L eq , R Load-a , L Load-a is unknown, so we use the one-cycle data before the fault to estimate the parameters using the least squares method.

[0116]

[0117] After solving, we get the assumed fault point x i Equivalent parameters estimated downstream of location

[0118] Furthermore, high-resistance ground fault parameter estimation

[0119] Estimate the fault point x i After the downstream equivalent parameters are set, press Figure 3 The ground branch current can be obtained as

[0120] I fault (n) = I xa (n)-I Load-a (n),n>N TM (5)

[0121] Where N TM Corresponding to the initial time T of high resistance ground fault m The corresponding sampling points.

[0122] Due to the breakdown characteristics of the arc, the ground branch current can be expressed as

[0123] I fault (n) = sgn (V xa (n)-U + )·(V xa (n)-U + ) / R f+sgn(-U - -V xa (n))·(V xa (n)-U - ) / R f (6)

[0124] The symbol function U + , U - They are the breakdown voltages of the arc in the positive and negative half cycles of the voltage respectively.

[0125] U in formula (6) + , U - and R f is unknown, so we use the data of one cycle after the fault to estimate the parameters using the least squares method.

[0126]

[0127] After solving, we get U + , U - and R f Estimated value of and

[0128] Furthermore, according to the estimated parameters from x i The voltage of the first node is calculated from the position to the first section of the line;

[0129] x i The position voltage is as follows

[0130]

[0131] According to formula (1) (2), the estimated voltage value of each node can be calculated:

[0132] Furthermore, the estimated deviation value is calculated

[0133]

[0134] Furthermore, the possible fault point location sequence set X = {x i After all the sequence values ​​in}, i=1…n are calculated, the fault location is calculated as follows

[0135]

[0136] In an optional embodiment, if Figure 3As shown, a detailed flow chart of a method for locating a high-resistance grounding fault in a distribution network, starting 201, the master station detects a fault 202, generates a possible fault point set 203, uses the post-fault data to push the node voltage forward 204, calculates the equivalent parameters downstream of the fault point 205, estimates the high-resistance grounding fault parameters 206, calculates the first node voltage based on the estimated parameters 207, calculates the estimated deviation value 208, i>N209, calculates the fault location 210, and outputs the fault location 211. The specific explanation is as follows: Figure 3 In the process, after the master detects a fault, the fault location process will be started. First, a set of possible fault points is generated, and then the node voltage is inferred using the post-fault data. Then, the equivalent parameters downstream of the fault point are calculated, and the high-resistance grounding fault parameters are estimated. Based on the estimated parameters, the first node voltage is inferred and the estimated deviation value is calculated. If the number of iterations i is greater than the set maximum number of iterations N, the fault location is calculated and finally output. The entire process ensures the accuracy and efficiency of fault location.

[0137] In summary, the present invention proposes a method for locating a high-resistance grounding fault in a distribution network, obtaining a first parameter of a distribution line in a target distribution network; obtaining a first fault data set according to the first parameter in combination with a preset first fault location model; estimating a first deviation value according to the first fault data set, and locating the fault according to the first deviation value estimation result. The search is calculated by generating a set of possible fault locations. An equivalent model of the downstream network of each fault point is established according to the voltage and current of each fault point. The fault current and arc parameters are estimated using the equivalent model. Then, the estimated high-resistance grounding fault parameters are used to calculate the estimated fault phase voltage at the source node where the distribution network protection (IED) is installed. The deviation between the estimated voltage and the measured voltage is used as a basis for determining the location of the high-resistance grounding fault, and finally the fault location of the distribution line high-resistance grounding fault is achieved.

[0138] This embodiment also provides a distribution network high-resistance grounding fault location system, including:

[0139] A data acquisition module, used to acquire a first parameter of a distribution line in a target distribution network;

[0140] A data set acquisition module, used to acquire a first fault data set according to the first parameter and in combination with a preset first fault location model;

[0141] The positioning module is used to estimate a first deviation value according to a first fault data set, and to locate the fault according to a result of the first deviation value estimation.

[0142] The above-mentioned unit modules may be embedded in or independent of a processor in a computer device in the form of hardware, or may be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to the above-mentioned modules.

[0143] This embodiment also provides a computer device, which may be a terminal, and its internal structure diagram may be as shown in FIG. Figure 5 As shown. The computer device includes a processor, a memory, a communication interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a method for locating a high-resistance grounding fault in a distribution network is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covered on the display screen, or a key, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.

[0144] This embodiment further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the following steps are implemented:

[0145] Obtaining a first parameter of a distribution line in a target distribution network;

[0146] According to the first parameter and in combination with a preset first fault location model, a first fault data set is acquired;

[0147] A first deviation value is estimated according to the first fault data set, and the fault is located according to the first deviation value estimation result.

[0148] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

[0149] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0150] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0151] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0152] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0153] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0154] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for locating a high-resistance grounding fault in a distribution network, characterized in that: include: Obtaining a first parameter of a distribution line in a target distribution network; According to the first parameter and in combination with a preset first fault location model, a first fault data set is acquired; A first deviation value is estimated according to the first fault data set, and fault location is performed according to the first deviation value estimation result.

2. The method for locating a high-resistance grounding fault in a distribution network according to claim 1, characterized in that: The acquiring of a first fault data set according to the first parameter and in combination with a preset first fault location model comprises: The first fault location model is any model whose input is the first parameter and whose output is the fault point location or a parameter related to the fault point location; The parameters related to the fault point location include at least a number of parameters related to the fault point location that can be used to obtain the fault point location.

3. The method for locating a high-resistance grounding fault in a distribution network as claimed in claim 2, characterized in that: The estimating a first deviation value according to the first fault data set comprises: The first fault data set is a combination set output by the first fault location model, and the first fault data set includes a plurality of fault point locations; The first deviation value is estimated according to the location sequence of the plurality of fault points in the first fault set.

4. The method for locating a high-resistance grounding fault in a distribution network as claimed in claim 3, characterized in that: The estimating a first deviation value according to the first fault data set further comprises: Establishing a first target inspection node set; The first target inspection node set includes all nodes to be tested in the distribution lines of the target distribution network; According to the sequence of the positions of the several fault points in the first fault set, the voltages of the subsequent nodes are calculated starting from the first node in the first target inspection node set along the fault path direction until the corresponding fault point position in the first fault set is reached.

5. The method for locating a high-resistance grounding fault in a distribution network as claimed in claim 4, characterized in that: The estimating a first deviation value according to the first fault data set further comprises: The voltages of subsequent nodes are calculated starting from the first node in the first target inspection node set along the fault path direction according to the location sequence of several fault points in the first fault set using one cycle data after the fault.

6. The method for locating a high-resistance grounding fault in a distribution network as claimed in claim 5, characterized in that: The estimating a first deviation value according to the first fault data set further comprises: According to the position sequence of several fault points in the first fault set, starting from the first node in the first target inspection node set, calculate the voltage of each subsequent node along the fault path direction until the corresponding fault point position in the first fault set, and record the voltage at this position as the first fault voltage; Calculate the downstream equivalent parameter at the fault point according to the first fault voltage; Acquire a high-resistance grounding fault parameter according to the downstream equivalent parameter; The node voltage is calculated according to the high-resistance grounding fault parameter.

7. The method for locating a high-resistance grounding fault in a distribution network as claimed in claim 6, characterized in that: The performing fault location according to the first deviation value estimation result includes: Calculating a first deviation value estimation result according to the node voltage calculated by the high-resistance grounding fault parameter and the actually measured node voltage; And fault location is performed according to the first deviation value estimation result.

8. A distribution network high-resistance grounding fault location system, characterized in that: include: A data acquisition module, used to acquire a first parameter of a distribution line in a target distribution network; A data set acquisition module, configured to acquire a first fault data set according to the first parameter and in combination with a preset first fault location model; A positioning module is used to estimate a first deviation value according to the first fault data set, and to locate the fault according to the first deviation value estimation result.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

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

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