Grounding grid corrosion positioning method and system

Abstract

The invention discloses a grounding grid corrosion positioning method and system, and the method comprises the steps: obtaining first data of a grounding grid, and obtaining a first curve and a second curve according to the first data; obtaining a first corrosion position according to the first curve and the second curve, and calculating a third curve of the first corrosion position; imaging is carried out in combination with the second curve and the third curve, an apparent resistivity plane graph is obtained, and the corrosion position of the grounding grid is obtained according to the apparent resistivity plane graph. Based on the transient electromagnetic method, excavation is not needed, power-off operation on the transformer substation is not needed, and waste of manpower and material resources is reduced; a two-stage detection method is adopted, a first corrosion position is obtained through first-stage detection, whether each grid is likely to be corroded or not can be determined, the pre-detection effect is achieved, and the detection cost is reduced; dense point detection is carried out in the second section, underground apparent resistivity distribution information can be mined, and corrosion positioning accuracy is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of grounding grid detection, and in particular to a grounding grid corrosion positioning method and system. Background Art

[0002] The grounding grid connects the electrical equipment in the substation to the earth. When the substation is closed or the electrical equipment in the substation fails, a large impact current will appear. At this time, the grounding grid can quickly lead it into the ground, playing an important role in protecting the safety of workers and reducing the risk of damage to electrical equipment. However, since the grounding grid is buried underground all year round, the oxygen, microorganisms, and stray currents in the soil will cause the grounding grid to corrode, its cross-sectional area will decrease, its resistivity will increase, and its drainage capacity will weaken. It may be difficult to play its due drainage role, posing a certain threat to the safety of electrical equipment and workers. Therefore, corrosion detection and accurate positioning of the grounding grid are urgently needed.

[0003] The main methods for corrosion detection of grounding grids include electrochemical analysis, node analysis, electromagnetic induction and transient electromagnetic methods. The disadvantage of the electrochemical analysis method is that it cannot be used to determine and locate the corrosion position of the grounding grid. The disadvantage of the node analysis method is that the measured grounding resistance is affected by many factors, resulting in low accuracy, low efficiency and poor operability. The disadvantage of the electromagnetic induction method is that the calculation is relatively lengthy, the implementation is complicated, and the substation itself has complex electromagnetic interference. The above methods have the disadvantages of low excavation efficiency, large power-off operation losses, and difficult device operation, which can easily cause a large waste of manpower and material resources. The disadvantage of the transient electromagnetic method is that the current research is not mature enough. 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. Therefore, the present invention provides a grounding grid corrosion positioning method to solve the problem of how to achieve efficient and accurate two-stage positioning of grounding grid corrosion based on transient electromagnetic method, so as to avoid unnecessary excavation and power outage operations and reduce waste of manpower and material resources.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides a method for locating grounding grid corrosion, comprising:

[0008] Acquire first data of the grounding grid, and acquire a first curve and a second curve according to the first data;

[0009] According to the first curve and the second curve, a first corrosion position is obtained, and a third curve of the first corrosion position is calculated;

[0010] The second curve and the third curve are combined for imaging to obtain an apparent resistivity plane map, and the location of grounding grid corrosion is obtained according to the apparent resistivity plane map.

[0011] As a preferred solution of the grounding grid corrosion positioning method of the present invention, wherein: according to the first curve and the second curve, obtaining the first corrosion position includes:

[0012] The apparent resistivity values ​​at the same time in the first curve and the second curve corresponding to each grid of the grounding grid are compared, and if the absolute value of the difference between the two exceeds a preset threshold, the first corrosion position is obtained.

[0013] As a preferred solution of the grounding grid corrosion positioning method of the present invention, wherein: combining the second curve and the third curve to perform imaging includes:

[0014] The apparent resistivity profile of the underground of the survey line is obtained according to the imaging of the second curve and the third curve of each survey point on the survey line.

[0015] As a preferred embodiment of the method for locating grounding grid corrosion according to the present invention, obtaining the apparent resistivity plane map includes:

[0016] The depth value of the grounding grid buried underground is determined according to the first data of the grounding grid, and the depth value is taken from the second curve and the third curve of each measuring point, and the apparent resistivity corresponding to each measuring point is imaged to obtain the apparent resistivity plane diagram of the part.

[0017] As a preferred solution of the method for locating grounding grid corrosion according to the present invention, obtaining the location of grounding grid corrosion according to the apparent resistivity plane map includes:

[0018] In the apparent resistivity profile, if the difference between the measuring point and the left and right measuring points is large, the location of the measuring point is the location of corrosion;

[0019] In the apparent resistivity plane diagram, if the measuring point is asymmetric and has a large difference from the surrounding area, the location of the measuring point is the location of corrosion.

[0020] As a preferred solution of the grounding grid corrosion positioning method of the present invention, the first curve includes:

[0021] Determine the position of each grid of the grounding grid in the substation according to the first data of the grounding grid, and then determine the position of the center of each grid;

[0022] When the diagnosed grounding grid is not corroded, a transient electromagnetic detection device is used to detect the center of each grid to obtain a curve of the secondary induced voltage value changing with time, and then the first curve is obtained.

[0023] As a preferred solution of the grounding grid corrosion positioning method of the present invention, obtaining the first corrosion position also includes:

[0024] After obtaining the first corrosion position, measurement points are set inside and around the grid according to the size of the grid, and each measurement point is detected using a transient electromagnetic detection device to obtain the secondary induced voltage value and calculate the second curve of each measurement point.

[0025] In a second aspect, the present invention provides a system for locating grounding grid corrosion, comprising:

[0026] An acquisition module, used for acquiring first data of the grounding grid;

[0027] A calculation module, used to obtain a first curve and a second curve according to the first data; obtain a first corrosion position according to the first curve and the second curve, and calculate a third curve of the first corrosion position;

[0028] The position acquisition module is used to combine the second curve and the third curve for imaging to obtain an apparent resistivity plane map, and obtain the position of the grounding grid corrosion according to the apparent resistivity plane map.

[0029] In a third aspect, the present invention provides a computing device, comprising:

[0030] Memory and processor;

[0031] The memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions. When the computer executable instructions are executed by the processor, the steps of the grounding grid corrosion locating method are implemented.

[0032] In a fourth aspect, the present invention provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the steps of the grounding grid corrosion locating method.

[0033] Compared with the prior art, the present invention has the following beneficial effects: the present invention is based on transient electromagnetic method, does not require excavation, does not require power-off operation of the substation, and reduces the waste of manpower and material resources; adopts a two-stage detection method, in which the first stage detects the first corrosion position, and can determine whether corrosion may occur in each grid, playing a role in pre-detection and reducing the cost of detection; the second stage performs dense point detection, which can component-excavate the underground apparent resistivity distribution information and improve the accuracy of corrosion positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] 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:

[0035] Figure 1 It is a schematic diagram of the overall process of the grounding grid corrosion location method according to one embodiment of the present invention;

[0036] Figure 2 A schematic diagram of measuring point settings for grounding grid corrosion locating in the first stage of a grounding grid corrosion locating method according to an embodiment of the present invention;

[0037] Figure 3 A schematic diagram of measuring point settings for grounding grid corrosion locating in the second stage of the grounding grid corrosion locating method according to an embodiment of the present invention;

[0038] Figure 4 A schematic diagram of an apparent resistivity cross section of a grounding grid corrosion location method according to an embodiment of the present invention;

[0039] Figure 5 A schematic diagram of the apparent resistivity plane of a grounding grid corrosion location method according to an embodiment of the present invention;

[0040] Figure 6 A schematic diagram of the internal structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0041] 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.

[0042] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0043] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0044] The present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0045] At the same time, in the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the system or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0046] In the present invention, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] Example 1

[0048] Reference Figure 1-5 , as an embodiment of the present invention, provides a grounding grid corrosion location method, comprising:

[0049] S100: Acquire first data of the grounding grid, and acquire a first curve and a second curve according to the first data;

[0050] In an optional embodiment, the first data may be drawings of the grounding grid, historical detection records of the grounding grid, design parameters of the grounding grid, etc.;

[0051] In the embodiment of the present application, the drawing data of the grounding grid is selected for subsequent description, and the drawing includes detailed data such as the size, position, material and original design resistivity of each grid;

[0052] Preferably, based on the first data of the grounding grid, the position of each grid of the grounding grid in the substation is determined, and then the position of the center of each grid is determined;

[0053] When the grounding grid under diagnosis is not corroded, the center of each grid is detected using a transient electromagnetic detection device to obtain a curve of the secondary induced voltage value changing with time, and then the first curve, i.e., the standard apparent resistivity curve of each grid, is obtained. Figure 2 shown.

[0054] In the embodiment of the present application, the specific process of obtaining the first curve is:

[0055] According to the drawings of the grounding grid, determine the position of each grid of the grounding grid in the substation, and then determine the position of the center of each grid. When the diagnosed grounding grid is not corroded, use a transient electromagnetic detection device to detect the center of each grid, and obtain the curve of the secondary induced voltage value changing with time, which is substituted into the following equation for solution:

[0056]

[0057] Where t is time, a is the radius of the coil in the transient electromagnetic detection device, erf is the error function in mathematical calculation, μ 0 is the vacuum magnetic permeability, I is the magnitude of the emitted pulse current, ε(t) is the secondary induced voltage value corresponding to time t, and u is the transient field parameter. Its corresponding relationship with the apparent resistivity ρ is as follows:

[0058]

[0059] Substituting the transient field parameter u obtained by the solution into the above formula for calculation, we can obtain the curve of apparent resistivity ρ changing with time;

[0060] The secondary induced voltage values ​​detected in each grid are calculated respectively to obtain a first curve, namely, a standard apparent resistivity curve group.

[0061] In an embodiment of the present application, when the diagnosed grounding grid has been corroded but the degree of corrosion is unknown, a transient electromagnetic detection device is used to detect the center of each grid of the diagnosed grounding grid, obtain the secondary induced voltage, and calculate the second curve, that is, the apparent resistivity curve of each grid.

[0062] S102: obtaining a first corrosion position according to the first curve and the second curve, and calculating a third curve of the first corrosion position;

[0063] Preferably, the apparent resistivity values ​​at the same time in the first curve and the second curve corresponding to each grid of the grounding grid are compared, and if the absolute value of the difference between the two exceeds a preset threshold, the first corrosion position is obtained;

[0064] In an optional embodiment, the preset threshold may be 5%, 10%, 15%, etc.;

[0065] For example, for the apparent resistivity curve of a certain grid of the diagnosed grounding grid, the corresponding apparent resistivity value is compared with the apparent resistivity value at the same time in the standard apparent resistivity curve of the grid within a certain time after the pulse current is turned off during detection by the transient electromagnetic detection device. If the absolute value of the difference between the two exceeds 10% of the apparent resistivity at that time in the standard apparent resistivity curve, it is considered that the grid may have been corroded; each grid is compared separately to determine whether each grid has been corroded.

[0066] Preferably, after obtaining the first corrosion position, measuring points are set inside and around the grid according to the size of the grid, and each measuring point is detected using a transient electromagnetic detection device to obtain a secondary induced voltage value, and a second curve of each measuring point is calculated;

[0067] In an optional embodiment, dense measurement points are set for the grid where corrosion may exist, and as many measurement points as possible are set in the grid;

[0068] For example, within each grid, a large grid is subdivided into smaller sub-grids according to a predetermined grid subdivision strategy, or a dense layout is performed within the area based on the distribution of abnormal resistivity areas in preliminary detection to ensure that each potential corrosion area can be adequately covered by detection; a certain number of measuring points are also set at the edge and surrounding areas of the grid to capture the boundary effects where corrosion may spread to the outside.

[0069] In the embodiment of the present application, when measuring points are set in various directions around the grid, the range thereof at least exceeds the length of one grid to ensure the accuracy of determining the corrosion position after the imaging operation. Figure 3 shown.

[0070] It should be noted that a two-stage detection method is adopted. The first stage of detection obtains the first corrosion position, which can determine whether corrosion may occur in each grid, play a role in pre-detection, and reduce the cost of detection; the second stage performs dense point detection, which can component-excavate the underground apparent resistivity distribution information and improve the accuracy of corrosion location.

[0071] In the embodiment of the present application, the specific process of obtaining the third curve is:

[0072] Calculate according to the second curve of each measuring point to obtain the corresponding third curve, i.e., the apparent depth curve;

[0073] For each apparent resistivity curve, the following calculations are performed:

[0074]

[0075] Among them, ρ r is the apparent resistivity used for imaging, t is the time, σ is the conductivity of the uniform half space, and the inverse of the apparent resistivity corresponding to time t is taken during calculation, μ 0 is the vacuum permeability, t j and t i are two adjacent time points in the apparent resistivity curve, ρ j and ρ i is the corresponding apparent resistivity, t ji is the average of two time points, d j and d i is the depth d corresponding to the two time points, H r is the same as ρ r The corresponding apparent depth, 0.441 is the optimization coefficient. Through the above calculation, the apparent resistivity ρ of the underground at a certain measuring point can be calculated according to the apparent resistivity change curve of the measuring point. r Depth of sight H r The change curve.

[0076] S104: combining the second curve and the third curve to perform imaging, obtaining an apparent resistivity plane map, and obtaining the location of grounding grid corrosion according to the apparent resistivity plane map;

[0077] Obtain the apparent resistivity profile of the underground of the survey line according to the imaging of the second curve and the third curve of each survey point on the survey line;

[0078] The depth of the grounding grid buried underground is determined according to the first data of the grounding grid, and the depth value is taken from the second curve and the third curve of each measuring point, and the apparent resistivity corresponding to each measuring point is imaged to obtain the apparent resistivity plane diagram of the part.

[0079] In the apparent resistivity profile, if the difference between the measuring point and the left and right measuring points is large, the location of the measuring point is the location of corrosion;

[0080] In the apparent resistivity plane diagram, if the measuring point is asymmetrical and has a large difference from the surrounding area, the location of the measuring point is the location of corrosion.

[0081] In the embodiment of the present application, the apparent resistivity profile is observed, and the location of the measuring point with a large difference from the left and right measuring points is the location of the corrosion; Figure 4As shown in the figure, for a grounding grid with 20% and 40% corrosion degree grids on a certain measuring line, in the apparent resistivity profile of a certain measuring line imaged, the location where the 40% corrosion occurs is quite different from the left and right measuring points, and the location where the 20% corrosion occurs is also somewhat different from the left and right measuring points.

[0082] Observe the apparent resistivity plane diagram and find the asymmetric measuring points and the measuring points that are greatly different from the surrounding areas, which are the locations of corrosion. Figure 5 As shown, for the grounding grids with 20%, 40%, 60%, and 80% corrosion degree grids, in the apparent resistivity plane diagrams obtained by imaging, the difference between the corroded positions and the uncorroded positions is quite obvious.

[0083] It should be noted that according to a grounding grid corrosion positioning method of the present invention, the present invention is based on transient electromagnetic method, does not require excavation, does not require power outage operation of the substation, and reduces the waste of manpower and material resources. A two-stage detection method is adopted. The first stage of detection can determine whether each grid is likely to be corroded, plays a role in pre-detection, and reduces the cost of detection; the second stage performs dense point detection, which can component excavate the underground apparent resistivity distribution information and improve the accuracy of corrosion positioning.

[0084] The above is a schematic scheme of a grounding grid corrosion locating method of this embodiment. It should be noted that the technical scheme of the grounding grid corrosion locating system and the technical scheme of the grounding grid corrosion locating method described above belong to the same concept. For details not described in detail in the technical scheme of the grounding grid corrosion locating system in this embodiment, please refer to the description of the technical scheme of the grounding grid corrosion locating method described above.

[0085] Example 2

[0086] This embodiment provides a grounding grid corrosion locating system, comprising:

[0087] Acquire first data of the grounding grid, and acquire a first curve and a second curve according to the first data;

[0088] According to the first curve and the second curve, a first corrosion position is obtained, and a third curve of the first corrosion position is calculated;

[0089] The second curve and the third curve are combined for imaging to obtain an apparent resistivity plane map, and the location of grounding grid corrosion is obtained according to the apparent resistivity plane map.

[0090] 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.

[0091] Example 3

[0092] This embodiment provides a computer device, which may be a terminal, and its internal structure diagram may be as follows: Figure 6 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 ground grid corrosion 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.

[0093] This embodiment also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the following is achieved: obtaining first data of the grounding grid, and obtaining a first curve and a second curve based on the first data; obtaining a first corrosion position based on the first curve and the second curve, and calculating a third curve of the first corrosion position; combining the second curve and the third curve for imaging to obtain an apparent resistivity plane map, and obtaining the position of the grounding grid corrosion based on the apparent resistivity plane map.

[0094] 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.

Claims

1. A method for locating grounding grid corrosion, characterized in that: include: Acquire first data of the grounding grid, and acquire a first curve and a second curve according to the first data; According to the first curve and the second curve, a first corrosion position is obtained, and a third curve of the first corrosion position is calculated; The second curve and the third curve are combined for imaging to obtain an apparent resistivity plane map, and the location of grounding grid corrosion is obtained according to the apparent resistivity plane map.

2. The method for locating grounding grid corrosion according to claim 1, characterized in that: According to the first curve and the second curve, obtaining the first corrosion position includes: The apparent resistivity values ​​at the same time in the first curve and the second curve corresponding to each grid of the grounding grid are compared, and if the absolute value of the difference between the two exceeds a preset threshold, the first corrosion position is obtained.

3. The method for locating grounding grid corrosion according to claim 1 or 2, characterized in that: Combining the second curve with the third curve to perform imaging includes, The apparent resistivity profile of the underground of the survey line is obtained according to the imaging of the second curve and the third curve of each survey point on the survey line.

4. The method for locating grounding grid corrosion according to claim 3, characterized in that: Obtaining the apparent resistivity plane diagram includes, The depth value of the grounding grid buried underground is determined according to the first data of the grounding grid, and the depth value is taken from the second curve and the third curve of each measuring point, and the apparent resistivity corresponding to each measuring point is imaged to obtain the apparent resistivity plane diagram of the part.

5. The method for locating grounding grid corrosion according to claim 4, characterized in that: The location of grounding grid corrosion is obtained according to the apparent resistivity plane map, including: In the apparent resistivity profile, if the difference between the measuring point and the left and right measuring points is large, the location of the measuring point is the location of corrosion; In the apparent resistivity plane diagram, if the measuring point is asymmetric and has a large difference from the surrounding area, the location of the measuring point is the location of corrosion.

6. The method for locating grounding grid corrosion according to claim 5, characterized in that: The first curve includes, Determine the position of each grid of the grounding grid in the substation according to the first data of the grounding grid, and then determine the position of the center of each grid; When the diagnosed grounding grid is not corroded, a transient electromagnetic detection device is used to detect the center of each grid to obtain a curve of the secondary induced voltage value changing with time, and then the first curve is obtained.

7. The method for locating grounding grid corrosion according to claim 6, characterized in that: Obtaining the first corrosion position also includes, After obtaining the first corrosion position, measurement points are set inside and around the grid according to the size of the grid, and each measurement point is detected using a transient electromagnetic detection device to obtain the secondary induced voltage value and calculate the second curve of each measurement point.

8. A system for locating grounding grid corrosion, characterized in that: include, An acquisition module, used for acquiring first data of the grounding grid; A calculation module, used to obtain a first curve and a second curve according to the first data; obtain a first corrosion position according to the first curve and the second curve, and calculate a third curve of the first corrosion position; The position acquisition module is used to combine the second curve and the third curve for imaging to obtain an apparent resistivity plane map, and obtain the position of the grounding grid corrosion according to the apparent resistivity plane map.

9. An electronic device, comprising: Memory and processor; The memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions. When the computer executable instructions are executed by the processor, the steps of the grounding grid corrosion locating method described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the steps of the grounding grid corrosion locating method according to any one of claims 1 to 7.

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