Distribution network grounding grid breakpoint diagnosis method, system, equipment and medium

Abstract

The invention discloses a distribution network grounding grid breakpoint diagnosis method, system and device and a medium, and the method comprises the steps: constructing a to-be-diagnosed distribution network grounding grid model according to the topology of a to-be-diagnosed distribution network grounding grid, and determining each node in the to-be-diagnosed distribution network grounding grid according to the to-be-diagnosed distribution network grounding grid model; a certain node is selected from all the nodes to serve as the center point of a circle, the radius of the circle is set, the earth surface magnetic flux density is obtained on the ground corresponding to the certain node, and the derivative of the earth surface magnetic flux density on the circle is calculated; and analyzing the breakpoint condition of the distribution network grounding grid to be diagnosed according to the derivatives of the ground magnetic flux density and the earth surface magnetic flux density on the circle. A magnetic field derivative method and a parallel computing technology are introduced, and the breakpoint condition of the distribution network grounding grid can be accurately analyzed by calculating the derivative of the surface magnetic flux density on a circle; the problems that in the prior art, the influence of electromagnetic interference on distribution network grounding grid fault diagnosis cannot be effectively solved, and a high-precision positioning result cannot be provided in a complex electromagnetic environment are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of diagnosis of breakpoints in a distribution network grounding grid, and particularly to a method, system, device and medium for diagnosing breakpoints in a distribution network grounding grid. Background Art

[0002] With the continuous development of the power system, as an important link in the power network, the health status of the distribution network grounding grid is directly related to the safety and stability of power equipment. Existing methods for diagnosing faults in distribution network grounding grids usually rely on resistance measurement, signal processing, and electromagnetic field detection. However, when faced with a complex electromagnetic environment and unstable soil resistivity, these methods are difficult to achieve high-precision fault location, resulting in errors in fault diagnosis and inability to meet the requirements of real-time detection and efficient diagnosis in large-scale distribution network grounding grid systems. At the same time, the topological structure of the distribution network grounding grid is complex, and traditional topological reconstruction methods have a large workload and low computational efficiency in practical applications, and cannot accurately complete the reconstruction of the topological structure and fault location in a short time.

[0003] In summary, the prior art cannot effectively solve the influence of electromagnetic interference on the fault diagnosis of the distribution network grounding grid, and cannot provide high-precision positioning results in a complex electromagnetic environment. Summary of the Invention

[0004] The present invention provides a method, system, device and medium for diagnosing breakpoints in a distribution network grounding grid, which is used to solve the problem that the prior art cannot effectively solve the influence of electromagnetic interference on the fault diagnosis of the distribution network grounding grid and cannot provide high-precision positioning results in a complex electromagnetic environment.

[0005] In view of this, in the first aspect of the present invention, a method for diagnosing breakpoints in a distribution network grounding grid is provided, and the method includes:

[0006] Construct a model of the distribution network grounding grid to be diagnosed according to the topology of the distribution network grounding grid to be diagnosed, and determine each node in the distribution network grounding grid to be diagnosed according to the model of the distribution network grounding grid to be diagnosed;

[0007] Select a certain node as the center point of a circle and set the radius of the circle from each node, obtain the surface magnetic flux density on the ground corresponding to the certain node, and calculate the derivative of the surface magnetic flux density on the circle;

[0008] Analyze the breakpoint situation of the distribution network grounding grid to be diagnosed according to the ground magnetic flux density and the derivative of the surface magnetic flux density on the circle.

[0009] Optionally, the analyzing the breakpoint situation of the distribution network grounding grid to be diagnosed according to the surface magnetic flux density and the derivative of the surface magnetic flux density on the circle includes:

[0010] Draw a schematic diagram of the derivative of the surface magnetic flux density on a circle, and analyze the break point situation of the power distribution network grounding grid to be diagnosed according to the peak situation of the schematic diagram and the nodes corresponding to the ground magnetic flux density.

[0011] Optionally, the analyzing the break point situation of the power distribution network grounding grid to be diagnosed according to the peak situation of the schematic diagram and the nodes corresponding to the ground magnetic flux density includes:

[0012] Judge whether each node has a corresponding peak according to the peak situation of the schematic diagram. If so, determine that the power distribution network grounding grid to be diagnosed is normal. Otherwise, determine the node corresponding to the non-occurring peak according to the surface magnetic flux density, and determine that the node is broken.

[0013] Optionally, the formula for calculating the derivative of the surface magnetic flux density on a circle is expressed as:

[0014] ;

[0015] In the formula, is the radius of the circle, is the magnetic permeability of the soil, is the current, is the length of the conductor, is the axis value in the coordinate system, is the depth at which the power distribution network grounding grid to be diagnosed is buried in the ground surface.

[0016] The second aspect of the present invention provides a diagnostic system for break points of a power distribution network grounding grid. The system includes:

[0017] A construction unit for constructing a power distribution network grounding grid model to be diagnosed according to the topology of the power distribution network grounding grid to be diagnosed, and determining each node in the power distribution network grounding grid to be diagnosed according to the power distribution network grounding grid model to be diagnosed;

[0018] A calculation unit for selecting a certain node as the center point of a circle and setting the radius of the circle from each node, obtaining the surface magnetic flux density on the ground corresponding to the certain node, and calculating the derivative of the surface magnetic flux density on the circle;

[0019] An analysis unit for analyzing the break point situation of the power distribution network grounding grid to be diagnosed according to the ground magnetic flux density and the derivative of the surface magnetic flux density on the circle.

[0020] Optionally, the analyzing the break point situation of the power distribution network grounding grid to be diagnosed according to the surface magnetic flux density and the derivative of the surface magnetic flux density on the circle includes:

[0021] Draw a schematic diagram of the derivative of the surface magnetic flux density on a circle, and analyze the break point situation of the power distribution network grounding grid to be diagnosed according to the peak situation of the schematic diagram and the nodes corresponding to the ground magnetic flux density.

[0022] Optionally, the analyzing the break point situation of the power distribution network grounding grid to be diagnosed according to the peak situation of the schematic diagram and the nodes corresponding to the ground magnetic flux density includes:

[0023] Judge whether each node has a corresponding peak according to the peak situation of the schematic diagram. If so, determine that the power distribution network grounding grid to be diagnosed is normal. Otherwise, determine the nodes corresponding to the non-occurring peaks according to the surface magnetic flux density, and determine that the break occurs at these nodes.

[0024] Optionally, the formula for calculating the derivative of the surface magnetic flux density on a circle is expressed as:

[0025] ;

[0026] In the formula, is the radius of the circle, is the magnetic permeability of the soil, is the current, is the length of the conductor, is the value of the axis in the coordinate system, is the depth at which the power distribution network grounding grid to be diagnosed is buried in the ground surface.

[0027] The third aspect of the present invention provides a diagnostic device for break points of a power distribution network grounding grid. The device includes a processor and a memory:

[0028] The memory is used to store program codes and transmit the program codes to the processor;

[0029] The processor is used to execute the steps of the diagnostic method for break points of the power distribution network grounding grid as described in the first aspect above according to the instructions in the program codes.

[0030] The fourth aspect of the present invention provides a computer-readable storage medium. The computer-readable storage medium is used to store program codes, and the program codes are used to execute the diagnostic method for break points of the power distribution network grounding grid as described in the first aspect above.

[0031] From the above technical solutions, it can be seen that the present invention has the following advantages:

[0032] The present invention provides a method for diagnosing breakpoints of a distribution network grounding grid, including: constructing a model of the distribution network grounding grid to be diagnosed according to the topology of the distribution network grounding grid to be diagnosed, and determining each node in the distribution network grounding grid to be diagnosed according to the model of the distribution network grounding grid to be diagnosed; selecting a certain node as the center point of a circle and setting the radius of the circle, obtaining the surface magnetic flux density on the ground corresponding to a certain node, and calculating the derivative of the surface magnetic flux density on the circle; analyzing the breakpoint situation of the distribution network grounding grid to be diagnosed according to the ground magnetic flux density and the derivative of the surface magnetic flux density on the circle.

[0033] The present invention introduces the magnetic field derivative method and parallel computing technology. By calculating the derivative of the surface magnetic flux density on the circle, it can be known through simulation that this method is not only applicable to simple branches, but also can diagnose damaged diagonal branches, is not affected by changes in soil resistivity, and is applicable to multi-layer soils. Thereby, the accuracy and efficiency of fault identification of the distribution network grounding grid are improved, and the problems that the prior art cannot effectively solve the influence of electromagnetic interference on the fault diagnosis of the distribution network grounding grid and cannot provide high-precision positioning results in a complex electromagnetic environment are solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0035] Figure 1 It is a schematic flow chart of a method for diagnosing breakpoints of a distribution network grounding grid provided by an embodiment of the present invention;

[0036] Figure 2 It is a schematic diagram for explaining the principle of the diagnosis method provided by an embodiment of the present invention;

[0037] Figure 3 It is a circle provided by an embodiment of the present invention points on the schematic diagram;

[0038] Figure 4 It is the magnetic flux density provided by an embodiment of the present invention the schematic diagram of the derivative on the circle;

[0039] Figure 5 It is a schematic diagram of a distribution network grounding grid model for simulation analysis provided by an embodiment of the present invention;

[0040] Figure 6 It is a schematic diagram for explaining the derivative method of breakpoint analysis of branch b9 provided by an embodiment of the present invention;

[0041] Figure 7 Schematic diagram for the break point analysis of the diagonal branch bd provided by the embodiment of the present invention;

[0042] Figure 8 Schematic diagram for the influence of soil resistivity on the derivative method provided by the embodiment of the present invention;

[0043] Figure 9 Schematic diagram of the distribution network grounding grid buried in two-layer soil provided by the embodiment of the present invention;

[0044] Figure 10 Schematic diagram for using multi-layer soil to analyze the derivative method provided by the embodiment of the present invention;

[0045] Figure 11 Schematic diagram of the structure of a diagnosis system for break points of a distribution network grounding grid provided by the embodiment of the present invention. Detailed implementation manners

[0046] To make the objectives, features, and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the embodiments described below are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0047] The following is the principle explanation of the present invention:

[0048] The distribution network grounding grid usually contains many branches and nodes. Here, a single current-carrying conductor is analyzed to explain the method. Figure 2 Shows a conductor A with a length of L placed along the y-axis. It is buried in a single-layer soil with a depth of h, and the magnetic permeability of the soil is μ. A direct current I flows through the conductor, and according to the Biot-Savart law, it will generate a magnetic flux density B above the ground. According to Figure 2 , the contribution of conductor A to the magnetic flux density B at point P(x, y, h) is expressed as:

[0049] (1)

[0050] Wherein, represents the direction of the current I, and R is the vector from the differential element dl to the point .

[0051] When solving equation (1), let , the magnetic flux density of and components can be obtained. Continue to derive , expressed as:

[0052] (2)

[0053] Derivative on the circle:

[0054] The derivative method is used to eliminate ECG (abbreviation of Electrocardiogram, meaning electrocardiogram) artifacts in EEG (abbreviation of Electroencephalogram, meaning electroencephalogram). Similarly, it is used to compensate for the frequency and amplitude losses of propagating seismic waves. In addition, it is also used to improve the resolution of GPR data, where GPR is Ground Penetrating Radar, used for non-destructive detection of underground structures, and analyzes the distribution and properties of underground substances by emitting electromagnetic waves and receiving the reflected signals.

[0055] To understand the role of the circle in this method, refer to Figure 3 . The circle is a geometric element in polar coordinates, specified by its radius r, angle θ = 2π radians, and the center of the circle. Only when the center of the circle is located at the origin of the coordinate system, the point is located on the circle . Mathematically, the circle can be expressed as:

[0056] (3)

[0057] To diagnose a damaged conductor, the position of the conductor is very important. For this purpose, in Figure 2 , the derivative calculation of the surface magnetic flux density is performed on the circle C. The center of the circle C is located at the origin O, thus fulfilling the conditions presented in Figure 3 . The result of the derivative on the circle C can be expressed by a mathematical formula as:

[0058] (4)

[0059] (5)

[0060] In equation (5), it can be seen that reaches its maximum value at θ = π / 2 radians and x = 0, which indicates the position of the buried conductor A. In addition, the result of equation (5) is illustrated in Figure 4 , and the illustrated result is completely consistent with the mathematical derivation. The peak of the magnetic flux density gradient is located at 1.57 radians, indicating the presence of conductor A along the y-axis. Since the magnetic field is evenly distributed on both sides of the current-carrying conductor, its derivative produces a peak at the position of the conductor. Now, the appearance of a peak at the conductor position indicates the flow of current, indicating that the conductor is normal. When the conductor is broken, it cannot conduct electricity. The absence of current means the absence of a magnetic field.

[0061] Based on the above principle, the present invention provides a method for diagnosing breakpoints of a distribution network grounding grid, and the specific diagnosis method is as follows.

[0062] Please refer to Figure 1 , a method for diagnosing breakpoints of a distribution network grounding grid provided in an embodiment of the present invention includes:

[0063] Step 101: Construct a model of the distribution network grounding grid to be diagnosed according to the topology of the distribution network grounding grid to be diagnosed, and determine each node in the distribution network grounding grid to be diagnosed according to the model of the distribution network grounding grid to be diagnosed.

[0064] It should be noted that in specific implementation, first, the topology of the distribution network grounding grid to be diagnosed can be obtained. It can be understood that the topology of the distribution network grounding grid to be diagnosed includes connection relationship information of each branch, etc. Therefore, according to the connection relationship information, a model of the distribution network grounding grid to be diagnosed is constructed through simulation software, and then each node in the distribution network grounding grid to be diagnosed is determined according to the model of the distribution network grounding grid to be diagnosed.

[0065] Step 102: Select a certain node as the center point of a circle and set the radius of the circle, obtain the surface magnetic flux density on the ground corresponding to a certain node, and calculate the derivative of the surface magnetic flux density on the circle.

[0066] It should be noted that in order to solve the derivative of the surface magnetic flux density on the circle, first, the circle in the surface needs to be determined. Specifically, select a certain node as the center point of the circle and set the radius of the circle, and obtain the surface magnetic flux density on the ground corresponding to a certain node, so as to calculate the derivative of the surface magnetic flux density on the circle. For the specific principle, please refer to the above principle description and will not be elaborated here.

[0067] Step 103: Analyze the breakpoint situation of the distribution network grounding grid to be diagnosed according to the ground magnetic flux density and the derivative of the surface magnetic flux density on the circle.

[0068] In one embodiment, step 103 includes: drawing a schematic diagram of the derivative of the surface magnetic flux density on the circle, and judging whether each node has a corresponding peak according to the peak situation of the schematic diagram. If so, it is determined that the distribution network grounding grid to be diagnosed is normal; otherwise, according to the surface magnetic flux density, determine the node corresponding to the unappeared peak, and determine that the node is broken.

[0069] It should be noted that the schematic diagram of the derivative of the surface magnetic flux density on the circle can be referred to Figure 4 , as described in the above principle, since the magnetic field is evenly distributed on both sides of the current-carrying conductor, its derivative generates a peak at the position of the conductor. Now, the appearance of a peak at the conductor position indicates the flow of current, indicating that the conductor is normal. When the conductor is broken, it cannot conduct electricity. Without current, there is no magnetic field. Therefore, in this step, it is judged whether each node has a corresponding peak according to the peak situation.

[0070] The following is a simulation example provided by the embodiments of the present invention. Through this simulation example, those skilled in the art can better understand the method for diagnosing breakpoints of the distribution network grounding grid provided by the present invention:

[0071] The present invention uses COMSOL Multiphysics 4.4 to simulate the feasibility of the proposed method. COMSOL works based on the finite element method (FEM). Under the AC / DC module, the magnetic field and electric field interfaces are used for simulation.

[0072] Simulation model:

[0073] As Figure 5 shown, Figure 5 the simulation model is shown. The simulation model adopts a 3×3 square grid composed of steel conductors. The conductivity of the conductors is , and the radius is 0.01 m. The size of the grid is 6 m×6 m, and the grid spacing is 3 m. The grid is buried in a single-layer soil 0.5 m deep from the ground surface, and the soil resistivity is 100 Ωm. The nodes are modeled from 1 to 9, and the branches are represented from b1 to b12. A diagonal branch bd connects nodes 5 and 9 and makes a 45° angle with branch b7. A DC current I = 10 A is injected from node 1 and flows out from node 9. As the current is distributed in the grid, the magnetic flux density (z component) is generated on the surface.

[0074] To perform breakpoint analysis on the proposed simulation model, two states are considered:

[0075] (1) Normal distribution network grounding grid, without breakpoints.

[0076] (2) Faulty distribution network grounding grid, with a 2-cm break in branch b9.

[0077] The derivative of the surface magnetic flux density is taken on a circle C0 centered at node 5. The radius of the circle is taken as 2.43 m. Figure 5 shows the circle and the derivative of on it.

[0078] From Figure 4 it can be seen that whether the conductor is normal is judged by the peak of the magnetic flux density gradient where the derivative of the surface magnetic flux density passes through the conductor position, and vice versa. When analyzing part (b) of Figure 6 , when the grid is normal (branch b9 is not broken), on the circle the The derivative has peaks at the following five positions: 0 radians (branch b7), 0.78 radians (branch bd), 1.57 radians (branch b9), 3.14 radians (branch b6), and 4.71 radians (branch b4). The presence of these peaks indicates that the corresponding branches are not broken. On the contrary, when branch b9 is broken, the peak at 1.57 radians (branch b9) disappears. This indicates that branch b9 has been broken.

[0079] The same method was also applied to the breakpoint analysis of the diagonal branch bd. Under normal conditions (branch bd not broken), a peak appears at 0.78 radians, which is the position of branch bd on When there is a 2 - cm break in branch bd, the peak at its position disappears. Figure 7 Shows the breakpoint analysis of branch bd.

[0080] Since the distribution network grounding grid is buried in the soil, the influence of soil resistivity changes on the proposed method was tested. In addition, the soil can be of single - layer or multi - layer structure, and the method was also simulated under multi - layer soil conditions.

[0081] Influence of soil resistivity:

[0082] The resistivity of the soil usually ranges from a few ohms to several hundred ohms depending on the location and weather conditions. Simulations of the derivative method for breakpoint diagnosis were carried out under different soil resistivities. The soil resistivity values considered in the simulations were 20 Ωm, 100 Ωm, and 1000 Ωm. In addition, the simulations were also carried out for the cases of normal grid and broken grid respectively.

[0083] As shown by Figure 8 part (a) shows the results on circle C0 under the condition of a normal distribution network grounding grid. The soil resistivity values considered were 20 Ωm, 100 Ωm, and 1000 Ωm. Figure 8 Part (b) shows the results on circle C0 under the condition of a disconnected distribution network grounding grid (diagonal branch bd). The soil resistivity values considered were 20 Ωm, 100 Ωm, and 1000 Ωm.

[0084] It can be seen that the soil resistivity has no influence on the derivative method. Regardless of the value of the soil resistivity, the position and amplitude of the peak remain unchanged. This may be due to the fact that the conductivity of the soil is too low compared to that of the steel conductor (4.032×10^6 S / m). Figure 8 The maximum percentage difference in part (b) is .

[0085] Multi - layer soil:

[0086] The resistivity of the soil varies with the increase in depth. The proposed method was simulated in the case of two-layer soil. Figure 9 A two-layer soil model is shown. The depth of the upper layer of soil is 0.2 m, and the depth of the lower layer of soil is 0.4 m. The resistivity values considered are 100 Ωm and 1000 Ωm. Figure 10 The influence of multi-layer soil on the proposed method is shown. The simulation was carried out under the condition of damage to the distribution network grounding grid (diagonal branch bd), and the positive reflection factor K and the negative reflection factor K were considered. The mathematical expression of the reflection factor K is as follows:

[0087] (6)

[0088] where, is the resistivity of the upper layer of soil, is the resistivity of the lower layer of soil.

[0089] Figure 10 Part (a) in shows the reflection coefficient when the distribution network grounding grid is buried in two-layer soil, on the circle of the results. Figure 10 Part (b) in shows the reflection coefficient K = 0.81 ( = 100Ωm and = 1000Ωm) when the distribution network grounding grid is buried in two-layer soil, on the circle of the results. It can be found that the derivative method for breakpoint diagnosis is also applicable to the distribution network grounding grid buried in multi-layer soil. The results show that both the amplitude and the peak position remain consistent. In addition, this method is not affected by the reflection coefficient K.

[0090] The present invention provides a method for diagnosing breakpoints of a distribution network grounding grid. By calculating the derivative of the surface magnetic flux density on a circle, this method is not only applicable to simple branches but also capable of diagnosing damaged diagonal branches. This is an obvious advantage of this method compared with other existing breakpoint diagnosis methods. Secondly, the present invention studies parameters such as soil resistivity change and multi-layer soil. The results show that this method is not affected by soil resistivity change and is applicable to multi-layer soil. The results show that this method can effectively diagnose breakpoints of the distribution network grounding grid without excavation. Further, this method is also applicable to the topology of the distribution network grounding grid with diagonal branches.

[0091] The above is a method for diagnosing breakpoints of a distribution network grounding grid provided in an embodiment of the present invention. The following is a diagnostic system for breakpoints of a distribution network grounding grid provided in an embodiment of the present invention.

[0092] Please refer to Figure 11, A diagnosis system for a breakpoint of a distribution network grounding grid provided in an embodiment of the present invention includes:

[0093] A construction unit 201, configured to construct a to-be-diagnosed distribution network grounding grid model according to the topology of the to-be-diagnosed distribution network grounding grid, and determine each node in the to-be-diagnosed distribution network grounding grid according to the to-be-diagnosed distribution network grounding grid model.

[0094] A calculation unit 202, configured to select a certain node as the center point of a circle and set the radius of the circle from each node, obtain the surface magnetic flux density on the ground corresponding to a certain node, and calculate the derivative of the surface magnetic flux density on the circle.

[0095] An analysis unit 203, configured to analyze the breakpoint situation of the to-be-diagnosed distribution network grounding grid according to the ground magnetic flux density and the derivative of the surface magnetic flux density on the circle.

[0096] Furthermore, an embodiment of the present invention also provides a diagnosis device for a breakpoint of a distribution network grounding grid. The device includes a processor and a memory:

[0097] The memory is configured to store program code and transmit the program code to the processor;

[0098] The processor is configured to execute the steps of the diagnosis method for a breakpoint of a distribution network grounding grid as described in the above method embodiment according to the instructions in the program code.

[0099] Furthermore, an embodiment of the present invention also provides a computer-readable storage medium. The computer-readable storage medium is configured to store program code, and the program code is used to execute the diagnosis method for a breakpoint of a distribution network grounding grid as described in the above method embodiment.

[0100] Those skilled in the art can clearly understand that for the convenience and conciseness of description, the specific working processes of the above-described system, device, and unit can refer to the corresponding processes in the foregoing method embodiments, and will not be described herein again.

[0101] In several embodiments provided by the present invention, it should be understood that the disclosed system, device, and method can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point, the displayed or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, and the indirect coupling or communication connection of devices or units may be in an electrical, mechanical, or other form.

[0102] The unit described as a separation component may or may not be physically separated, and the component displayed as a unit may or may not be a physical unit, that is, it may be located in one place or may be distributed across multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0103] In addition, each functional unit in various embodiments of the present invention may be integrated into a processing unit, may exist separately as individual physical units, or two or more units may be integrated into one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0104] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in various embodiments of the present invention. The aforementioned storage medium includes: USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs and other various media that can store program codes.

[0105] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of various embodiments of the present invention.

Claims

1. A diagnostic method for breakpoints of a distribution network grounding grid, characterized in that, Including: Construct a to-be-diagnosed distribution network grounding grid model according to the topology of the to-be-diagnosed distribution network grounding grid, and determine each node in the to-be-diagnosed distribution network grounding grid according to the to-be-diagnosed distribution network grounding grid model; Select a certain node from each node as the center point of a circle and set the radius of the circle, obtain the surface magnetic flux density on the ground corresponding to the certain node, and calculate the derivative of the surface magnetic flux density on the circle; Analyze the break point situation of the to-be-diagnosed distribution network grounding grid according to the ground magnetic flux density and the derivative of the surface magnetic flux density on the circle.

2. The diagnostic method for the break point of the distribution network grounding grid according to claim 1, wherein, The analyzing the break point situation of the to-be-diagnosed distribution network grounding grid according to the surface magnetic flux density and the derivative of the surface magnetic flux density on the circle includes: Draw a schematic diagram of the derivative of the surface magnetic flux density on the circle, and analyze the break point situation of the to-be-diagnosed distribution network grounding grid according to the peak situation of the schematic diagram and the node corresponding to the ground magnetic flux density.

3. The diagnostic method for the breakpoint of the distribution network grounding grid according to claim 2, characterized in that The analyzing the break point situation of the to-be-diagnosed distribution network grounding grid according to the peak situation of the schematic diagram and the node corresponding to the ground magnetic flux density includes: Judge whether each node has a corresponding peak according to the peak situation of the schematic diagram. If so, determine that the to-be-diagnosed distribution network grounding grid is normal. Otherwise, determine the node corresponding to the unappeared peak according to the surface magnetic flux density, and determine that the node is broken.

4. The diagnostic method for the breakpoint of the distribution network grounding grid according to claim 1, characterized in that, The formula for calculating the derivative of the surface magnetic flux density on the circle is expressed as: ； Wherein, is the radius of the circle, is the magnetic permeability of the soil, is the current, is the length of the conductor, is the value of the axis in the coordinate system, is the depth at which the distribution network grounding grid to be diagnosed is buried in the ground surface.

5. A diagnostic system for breakpoints of a distribution network grounding grid, characterized in that, Including: A construction unit for constructing a to-be-diagnosed distribution network grounding grid model according to the topology of the to-be-diagnosed distribution network grounding grid, and determining each node in the to-be-diagnosed distribution network grounding grid according to the to-be-diagnosed distribution network grounding grid model; A calculation unit for selecting a certain node from each node as the center point of a circle and setting the radius of the circle, obtaining the surface magnetic flux density on the ground corresponding to the certain node, and calculating the derivative of the surface magnetic flux density on the circle; An analysis unit for analyzing the break point situation of the to-be-diagnosed distribution network grounding grid according to the ground magnetic flux density and the derivative of the surface magnetic flux density on the circle.

6. The diagnostic system for the breakpoint of the distribution network grounding grid according to claim 5, characterized in that, The analyzing the break point situation of the to-be-diagnosed distribution network grounding grid according to the surface magnetic flux density and the derivative of the surface magnetic flux density on the circle includes: Draw a schematic diagram of the derivative of the surface magnetic flux density on the circle, and analyze the break point situation of the to-be-diagnosed distribution network grounding grid according to the peak situation of the schematic diagram and the node corresponding to the ground magnetic flux density.

7. The diagnostic system for the breakpoint of the distribution network grounding grid according to claim 6, characterized in that, The analyzing the break point situation of the to-be-diagnosed distribution network grounding grid according to the peak situation of the schematic diagram and the node corresponding to the ground magnetic flux density includes: Judge whether each node has a corresponding peak according to the peak situation of the schematic diagram. If so, determine that the to-be-diagnosed distribution network grounding grid is normal. Otherwise, determine the node corresponding to the unappeared peak according to the surface magnetic flux density, and determine that the node is broken.

8. The diagnostic system for the break point of the distribution network grounding grid according to claim 5, characterized in that, The formula for calculating the derivative of the surface magnetic flux density on the circle is expressed as: ； Wherein, is the radius of the circle, is the magnetic permeability of the soil, is the current, is the length of the conductor, is the value of the axis in the coordinate system, is the depth at which the distribution network grounding grid to be diagnosed is buried in the ground surface.

9. A diagnostic device for a breakpoint of a distribution network grounding grid, characterized in that, The device includes a processor and a memory: The memory is used for storing program codes and transmitting the program codes to the processor; The processor is used for executing the diagnostic method for the break point of the distribution network grounding grid according to any one of claims 1-4 according to the instructions in the program codes.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used to store program codes, and the program codes are used to execute the diagnostic method for the breakpoints of the distribution network grounding grid according to any one of claims 1-4.

Images