Method and system for measuring grounding resistance of concrete pole under natural grounding

Abstract

The invention relates to a method and a system for measuring grounding resistance of a concrete pole under natural grounding, and the method comprises the following steps: arranging a conductive copper bar on a detection pole, and connecting a grounding resistance measuring instrument through the conductive copper bar; two test lines are led out through a grounding resistance measuring instrument, grounding probes are connected to the tail ends of the test lines, the two grounding probes are inserted into the ground near a detection electric pole in an initial arrangement mode, a conductive copper bar serves as a grounding electrode, the two grounding probes serve as a voltage electrode and a current electrode respectively, and an apparent grounding resistance measurement value is obtained through the grounding resistance measuring instrument; the arrangement mode of the two grounding probes is adjusted, the two grounding probes are inserted into the ground near the detection electric pole according to the adjusted arrangement mode, a compensation grounding resistance measurement value is obtained, and the arrangement mode of the two grounding probes is adjusted at least twice; and calculating a corrected grounding resistance value according to the compensation grounding resistance measurement value and the apparent grounding resistance measurement value.

Description

Technical Field

[0001] The invention relates to a method and a system for measuring the grounding resistance of a concrete pole under natural grounding, belonging to the technical field of pole parameter measurement. Background Art

[0002] The grounding resistance of concrete poles plays a key role in the safety of transmission lines. It has an important impact on the safe operation of power systems. Failure to meet the requirements of grounding resistance will cause safety accidents and damage to grounding lines. Affected by the anisotropy of soil resistivity, uneven soil distribution and test current field, the current three-pole method for measuring grounding resistance has large errors. Summary of the invention

[0003] In order to solve the above problems existing in the prior art, the present invention proposes a method for measuring the grounding resistance of a concrete pole under natural grounding.

[0004] The technical solution of the present invention is as follows:

[0005] On the one hand, the present invention provides a method for measuring the grounding resistance of a concrete pole under natural grounding, comprising the following steps:

[0006] A conductive copper strip is set on the detection pole, and a ground resistance measuring instrument is connected through the conductive copper strip;

[0007] Lead out two test lines through the ground resistance meter, connect the grounding probes at the ends of the test lines, insert the two grounding probes into the ground near the detection pole in the initial arrangement, use the conductive copper bar as the grounding electrode, and the two grounding probes as the voltage electrode and the current electrode respectively, and obtain the apparent ground resistance measurement value through the ground resistance meter;

[0008] Adjust the arrangement of the two grounding probes, insert the two grounding probes into the ground near the detection pole according to the adjusted arrangement, obtain the compensation grounding resistance measurement value, and adjust the arrangement of the two grounding probes at least twice;

[0009] The corrected ground resistance value is calculated based on the compensated ground resistance measurement value and the apparent ground resistance measurement value.

[0010] As a preferred embodiment, the two grounding probes are initially arranged as follows:

[0011] The first grounding probe is set at a position where the straight-line distance from the detection pole is N1, and the second grounding probe is set on the straight-line extension line between the detection pole and the first grounding probe, and the straight-line distance between the second grounding probe and the first grounding probe is N1.

[0012] As a preferred implementation, the method of adjusting the arrangement of the two grounding probes includes:

[0013] Adjust the straight-line distance between the first grounding probe and the detection pole so that the straight-line distance between the first grounding probe and the detection pole is less than N1;

[0014] Adjust the straight-line distance between the second grounding probe and the first grounding probe so that the straight-line distance between the second grounding probe and the first grounding probe is greater than N1, and the straight-line distance between the second grounding probe and the detection pole is equal to twice N1.

[0015] As a preferred implementation, the method of adjusting the arrangement of the two grounding probes includes:

[0016] Adjust the position of the second grounding probe so that the straight-line distance between the second grounding probe and the detection pole is equal to N1, and the central angle of the arc with the detection poles as the center and the first and second grounding probes as endpoints is within a preset range.

[0017] As a preferred embodiment, the arrangement of the two grounding probes is adjusted twice to obtain the first compensated grounding resistance measurement value and the second compensated grounding resistance measurement value; the step of calculating the corrected grounding resistance value according to the compensated grounding resistance measurement value and the apparent grounding resistance measurement value is specifically as follows:

[0018] Set the resistance tolerance value α%, if Then take is the ground resistance value after correction;

[0019] Wherein, Z is the apparent grounding resistance measurement value, Z1 is the first compensated grounding resistance measurement value, and Z2 is the second compensated grounding resistance measurement value;

[0020] like Then the difference D1 and D2 between the first compensated grounding resistance measurement value Z1, the second compensated grounding resistance measurement value Z2 and the apparent grounding resistance measurement value Z are taken as the second correction target weight and the first correction target weight respectively, that is, D1 = | Z1-Z | , D2= | Z2-Z | ;

[0021] The corrected grounding resistance Z3 is calculated by the following formula:

[0022]

[0023] like Then take the corrected grounding resistance Z3 as the corrected grounding resistance value;

[0024] like The second compensation grounding resistance measurement value Z2 and the corrected grounding resistance Z3 are corrected again, and the correction process is repeated until the calculated corrected grounding resistance meets the requirements.

[0025] As a preferred embodiment, a single-head nut is fixed at the stirrup of the detection pole, and power glue is applied at the fixed position, and the conductive copper strip is fixedly connected to the single-head nut.

[0026] As a preferred embodiment, the single-head nut is welded to the stirrup of the detection pole, and the conductive copper strip is welded to the single-head nut.

[0027] On the other hand, the present invention also provides a system for measuring grounding resistance of a concrete pole under natural grounding, comprising:

[0028] Ground resistance meter, conductive copper strip, test line, ground probe and resistance correction module;

[0029] The conductive copper strip is arranged on the detection pole, and the two ends of the conductive copper strip are respectively connected to the ground resistance measuring instrument and the detection pole;

[0030] Two test lines are connected to the input end of the ground resistance measuring instrument, and the ground probe is arranged at the end of the test line;

[0031] Among them, two grounding probes are inserted into the ground near the detection pole in the initial arrangement, with a conductive copper bar as the grounding electrode, and the two grounding probes as the voltage electrode and the current electrode respectively, and the apparent grounding resistance measurement value is obtained through the grounding resistance measuring instrument;

[0032] Adjust the arrangement of the two grounding probes, insert the two grounding probes into the ground near the detection pole according to the adjusted arrangement, obtain the compensation grounding resistance measurement value, and adjust the arrangement of the two grounding probes at least twice;

[0033] The resistance correction module is used to input the compensated grounding resistance measurement value and the apparent grounding resistance measurement value, and calculate the corrected grounding resistance value according to the compensated grounding resistance measurement value and the apparent grounding resistance measurement value.

[0034] On the other hand, the present invention also proposes an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for measuring the grounding resistance of a concrete pole under natural grounding as described in any embodiment of the present invention is implemented.

[0035] On the other hand, the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for measuring the grounding resistance of a concrete pole under natural grounding as described in any embodiment of the present invention.

[0036] The present invention has the following beneficial effects:

[0037] The present invention discloses a method and system for measuring the grounding resistance of a concrete pole under natural grounding, which solves the gap in the measurement of the grounding resistance of the traditional concrete pole body and adds a compensation correction method to reduce the mechanical error caused by uneven soil resistivity and traditional three-wire measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic diagram of a method flow of an embodiment of the present invention;

[0039] Figure 2 A schematic diagram of the arrangement of a measuring device in an embodiment of the present invention;

[0040] Figure 3 Schematic diagram of the initial arrangement of two grounding probes in an embodiment of the present invention;

[0041] Figure 4 A schematic diagram of an adjusted arrangement of two grounding probes in an embodiment of the present invention;

[0042] Figure 5 A schematic diagram of another adjusted arrangement of two grounding probes in an embodiment of the present invention;

[0043] Figure 6 Flow chart of correcting resistance in an embodiment of the present invention.

[0044] The accompanying drawings in the figure are marked as follows:

[0045] 1. Detection pole; 2. Conductive copper strip; 3. Test line; 4. Grounding probe; 5. Grounding resistance meter; 6. Receiving current clamp. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] It should be understood that the step numbers used in this document are only for convenience of description and are not intended to limit the order in which the steps are executed.

[0048] It should be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0049] The terms “include” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0050] The term "and / or" means and includes any and all possible combinations of one or more of the associated listed items.

[0051] Embodiment 1:

[0052] See also Figure 1 and Figure 2 This embodiment provides a method for measuring the grounding resistance of a concrete pole under natural grounding, which specifically includes the following steps:

[0053] S100, performing initial setting of the measuring device, including setting a conductive copper bar 2 on the detection pole 1, and connecting a ground resistance measuring instrument 5 through the conductive copper bar 2;

[0054] S200, perform preliminary measurement, lead out the test line 3 through the ground resistance measuring instrument 5, connect the grounding probe 4 at the end of the test line 3, insert the two grounding probes 4 into the ground near the detection pole 1 in the initial arrangement, and use the two grounding probes 4 as voltage electrodes and current electrodes respectively to obtain the apparent ground resistance measurement value through the ground resistance measuring instrument 5; connect the receiving current clamp 6, voltage electrode P, current electrode C and conductive copper bar 2 through the corresponding interface of the ground resistance measuring instrument 5 of the test line 3. The receiving current clamp 6 is placed on the conductive copper bar 2 close to the pole, and the two test lines 3 are connected to the conductive copper bar 2 far away from the pole through the iron clamp to act as the grounding electrode and auxiliary grounding electrode.

[0055] S300, performing compensation measurement, adjusting the arrangement of the two grounding probes 4, inserting the two grounding probes 4 into the ground near the detection pole 1 according to the adjusted arrangement, obtaining the compensation grounding resistance measurement value, and adjusting the arrangement of the two grounding probes 4 at least twice;

[0056] S400: Calculate a corrected grounding resistance value according to the compensated grounding resistance measurement value and the apparent grounding resistance measurement value.

[0057] See also Figure 3 As an implementation method of this embodiment, the two grounding probes 4 are initially arranged as follows:

[0058] The first grounding probe 4 is set at a position with a straight-line distance of 2.5 m from the detection pole 1 , and the second grounding probe 4 is set on the straight-line extension line between the detection pole 1 and the first grounding probe 4 , and the straight-line distance between the second grounding probe 4 and the first grounding probe 4 is 2.5 m.

[0059] See also Figure 4 As an implementation of this embodiment, the method of adjusting the arrangement of the two grounding probes 4 includes:

[0060] The straight-line distance between the first grounding probe 4 and the detection pole 1 is adjusted so that the straight-line distance between the first grounding probe 4 and the detection pole 1 is smaller than N1; in this embodiment, the straight-line distance between the first grounding probe 4 and the detection pole 1 is 1.9 m.

[0061] The straight-line distance between the second grounding probe 4 and the first grounding probe 4 is adjusted so that the straight-line distance between the second grounding probe 4 and the first grounding probe 4 is greater than N1. In this embodiment, the straight-line distance between the second grounding probe 4 and the first grounding probe 4 is 3.1 m, and the straight-line distance between the second grounding probe 4 and the detection pole 1 is equal to twice N1.

[0062] See also Figure 5 As an implementation of this embodiment, the method of adjusting the arrangement of the two grounding probes 4 includes:

[0063] The position of the second grounding probe 4 is adjusted so that the straight-line distance between the second grounding probe 4 and the detection pole 1 is equal to N1, and the central angle of the arc with the detection pole 1 as the center and the first grounding probe 4 and the second grounding probe 4 as endpoints is within a preset range. In this embodiment, the preset range is 28° to 30°.

[0064] See Figure 6 As a preferred implementation of this embodiment, the arrangement of the two grounding probes 4 is adjusted twice to obtain the first compensated grounding resistance measurement value and the second compensated grounding resistance measurement value; the step of calculating the corrected grounding resistance value according to the compensated grounding resistance measurement value and the apparent grounding resistance measurement value is specifically as follows:

[0065] Set the resistance tolerance value α%, if Then take is the ground resistance value after correction;

[0066] Wherein, Z is the apparent grounding resistance measurement value, Z1 is the first compensated grounding resistance measurement value, and Z2 is the second compensated grounding resistance measurement value;

[0067] like Then the difference D1 and D2 between the first compensated grounding resistance measurement value Z1, the second compensated grounding resistance measurement value Z2 and the apparent grounding resistance measurement value Z are taken as the second correction target weight and the first correction target weight respectively, that is, D1 = | Z1-Z | , D2= | Z2-Z | ;

[0068] The corrected grounding resistance Z3 is calculated by the following formula:

[0069]

[0070] like Then take the corrected grounding resistance Z3 as the corrected grounding resistance value;

[0071] like Then the second compensation grounding resistance measurement value Z2 and the corrected grounding resistance Z3 are corrected again, that is, the calculated difference E1= | Z3-Z1 | , E2= | Z2-Z1 | , and then calculate the new correction resistance Z4:

[0072]

[0073] judge Is it less than or equal to α%, if yes, then output Z4 is the final correction resistance, otherwise the correction process is continued until the calculated correction grounding resistance Z n Meets the requirements.

[0074] As a preferred implementation mode of this embodiment, single-head nuts are pre-buried at three stirrup positions 0.5m, 1m and 1.45m above the buried depth of the detection pole 1, and power glue is applied at the fixed positions. The conductive copper strip 2 is fixedly connected to any single-head nut during a single measurement.

[0075] Take a 12-meter pole buried 2 meters deep as an example. According to the above method, the grounding resistance of the natural grounding of the concrete pole is measured at three locations of conductive copper strips. The grounding resistance measurement values ​​R1, R2, and R3 at 0.5m, 1m, and 1.45m above the ground are obtained.

[0076] Different positions of the vertical measurement points on the pole will lead to different resistances inside the pole for the test current, resulting in measurement errors. Considering the influence of the upper part of the concrete pole measurement point on the measurement results, the following solution is proposed to eliminate the measurement point position error.

[0077] The measurement resistance error caused by different current dissipation at 0.5m and 1.45m above the ground is:

[0078] ΔR1=R1-R3;

[0079] Because the measurement positions at the pole root and 1m above the ground are different (accounting for 1 / 10 of the aboveground part of the pole), the measurement resistance error caused by different current dissipation is:

[0080] ΔR2=R-R2.

[0081] The measurement errors caused by current dissipation are consistent in both cases. Therefore, the actual grounding resistance of the pole is:

[0082] R=R1+R2-R3.

[0083] Based on the above implementation, this embodiment can eliminate the measurement error caused by the different positions of the vertical measurement points of the pole.

[0084] As a preferred implementation of this embodiment, the single-head nut is welded to the stirrup of the detection pole 1, and the conductive copper strip 2 is welded to the single-head nut.

[0085] Embodiment 2:

[0086] This embodiment provides a system for measuring grounding resistance of a concrete pole under natural grounding, including:

[0087] Ground resistance meter, conductive copper strip, test line, ground probe and resistance correction module;

[0088] The conductive copper strip is arranged on the detection pole, and the two ends of the conductive copper strip are respectively connected to the ground resistance measuring instrument and the detection pole;

[0089] Two test lines are connected to the input end of the ground resistance measuring instrument, and the ground probe is arranged at the end of the test line;

[0090] Among them, two grounding probes are inserted into the ground near the detection pole in the initial arrangement, with a conductive copper bar as the grounding electrode, and the two grounding probes as the voltage electrode and the current electrode respectively, and the apparent grounding resistance measurement value is obtained through the grounding resistance measuring instrument;

[0091] Adjust the arrangement of the two grounding probes, insert the two grounding probes into the ground near the detection pole according to the adjusted arrangement, obtain the compensation grounding resistance measurement value, and adjust the arrangement of the two grounding probes at least twice;

[0092] The resistance correction module is used to input the compensated grounding resistance measurement value and the apparent grounding resistance measurement value, and calculate the corrected grounding resistance value according to the compensated grounding resistance measurement value and the apparent grounding resistance measurement value.

[0093] Embodiment three:

[0094] This embodiment proposes an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, a method for measuring the grounding resistance of a concrete pole under natural grounding as described in any embodiment of the present invention is implemented.

[0095] Embodiment 4:

[0096] This embodiment provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, a method for measuring the grounding resistance of a concrete pole under natural grounding as described in any embodiment of the present invention is implemented.

[0097] In the embodiments of the present application, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, c can be single or multiple.

[0098] Those of ordinary skill in the art will appreciate that the various units and algorithm steps described in the embodiments disclosed herein can be implemented in a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0099] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0100] In several embodiments provided in the present application, if any function 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 this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory; hereinafter referred to as: ROM), random access memory (Random Access Memory; hereinafter referred to as: RAM), disk or optical disk, and other media that can store program codes.

[0101] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for measuring the grounding resistance of a concrete pole under natural grounding, characterized in that: The following steps are involved: A conductive copper strip is set on the detection pole, and a ground resistance measuring instrument is connected through the conductive copper strip; Lead out two test lines through the ground resistance meter, connect the grounding probes at the ends of the test lines, insert the two grounding probes into the ground near the detection pole in the initial arrangement, use the conductive copper bar as the grounding electrode, and the two grounding probes as the voltage electrode and the current electrode respectively, and obtain the apparent ground resistance measurement value through the ground resistance meter; Adjust the arrangement of the two grounding probes, insert the two grounding probes into the ground near the detection pole according to the adjusted arrangement, obtain the compensation grounding resistance measurement value, and adjust the arrangement of the two grounding probes at least twice; The corrected ground resistance value is calculated based on the compensated ground resistance measurement value and the apparent ground resistance measurement value.

2. The method for measuring the grounding resistance of a concrete pole under natural grounding according to claim 1 is characterized in that: The two grounding probes are initially arranged as follows: The first grounding probe is set at a position where the straight-line distance from the detection pole is N1, and the second grounding probe is set on the straight-line extension line between the detection pole and the first grounding probe, and the straight-line distance between the second grounding probe and the first grounding probe is N1.

3. The method for measuring the grounding resistance of a concrete pole under natural grounding according to claim 2 is characterized in that: The method of adjusting the arrangement of the two grounding probes includes: Adjust the straight-line distance between the first grounding probe and the detection pole so that the straight-line distance between the first grounding probe and the detection pole is less than N1; Adjust the straight-line distance between the second grounding probe and the first grounding probe so that the straight-line distance between the second grounding probe and the first grounding probe is greater than N1, and the straight-line distance between the second grounding probe and the detection pole is equal to twice N1.

4. The method for measuring the grounding resistance of a concrete pole under natural grounding according to claim 2 is characterized in that: The method of adjusting the arrangement of the two grounding probes includes: Adjust the position of the second grounding probe so that the straight-line distance between the second grounding probe and the detection pole is equal to N1, and the central angle of the arc with the detection poles as the center and the first and second grounding probes as endpoints is within a preset range.

5. The method for measuring the grounding resistance of a concrete pole under natural grounding according to claim 1 is characterized in that: The arrangement of the two grounding probes is adjusted twice to obtain a first compensated grounding resistance measurement value and a second compensated grounding resistance measurement value; the steps of calculating the corrected grounding resistance value according to the compensated grounding resistance measurement value and the apparent grounding resistance measurement value are specifically as follows: Set the resistance tolerance value α%, if Then take is the ground resistance value after correction; Wherein, Z is the apparent grounding resistance measurement value, Z1 is the first compensated grounding resistance measurement value, and Z2 is the second compensated grounding resistance measurement value; like Then the differences D1 and D2 between the first compensated grounding resistance measurement value Z1, the second compensated grounding resistance measurement value Z2 and the apparent grounding resistance measurement value Z are taken as the second correction target weight and the first correction target weight, respectively, that is, D1 = |Z1-Z|, D2 = |Z2-Z|; The corrected grounding resistance Z3 is calculated by the following formula: like Then take the corrected grounding resistance Z3 as the corrected grounding resistance value; like The second compensation grounding resistance measurement value Z2 and the corrected grounding resistance Z3 are corrected again, and the correction process is repeated until the calculated corrected grounding resistance meets the requirements.

6. The method for measuring the grounding resistance of a concrete pole under natural grounding according to claim 1 is characterized by: A single-head nut is fixed at the stirrup of the detection pole, and power glue is applied at the fixed position. The conductive copper strip is fixedly connected to the single-head nut.

7. The method for measuring the grounding resistance of a concrete pole under natural grounding according to claim 6 is characterized by: The single-head nut is welded to the stirrup of the detection pole, and the conductive copper strip is welded to the single-head nut.

8. A system for measuring ground resistance of a concrete pole under natural grounding, characterized in that: include: Ground resistance meter, conductive copper strip, test line, ground probe and resistance correction module; The conductive copper strip is arranged on the detection pole, and the two ends of the conductive copper strip are respectively connected to the ground resistance measuring instrument and the detection pole; Two test lines are connected to the input end of the ground resistance measuring instrument, and the ground probe is arranged at the end of the test line; Among them, two grounding probes are inserted into the ground near the detection pole in the initial arrangement, with a conductive copper bar as the grounding electrode, and the two grounding probes as the voltage electrode and the current electrode respectively, and the apparent grounding resistance measurement value is obtained through the grounding resistance measuring instrument; Adjust the arrangement of the two grounding probes, insert the two grounding probes into the ground near the detection pole according to the adjusted arrangement, obtain the compensation grounding resistance measurement value, and adjust the arrangement of the two grounding probes at least twice; The resistance correction module is used to input the compensated grounding resistance measurement value and the apparent grounding resistance measurement value, and calculate the corrected grounding resistance value according to the compensated grounding resistance measurement value and the apparent grounding resistance measurement value.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the method for measuring the grounding resistance of a concrete pole under natural grounding as described in any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method for measuring the grounding resistance of a concrete pole under natural grounding as described in any one of claims 1 to 7 is implemented.

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