A method, system and device for detecting corrosion of macro cells in power transmission and transformation grounding grid

Abstract

The present invention relates to the technical field of grounding corrosion detection, and discloses a method, system and equipment for detecting corrosion of macro-batteries in a power transmission and transformation grounding grid. The system of the present invention comprises a test module and a corrosion assessment module; the test module comprises an electrode unit, a high-resistance voltage measurement unit and a zero-resistance current measurement unit; an electrode unit is respectively arranged on two soil macro-battery corrosion test points; the electrode unit comprises a reference electrode and a working electrode of the same material as the grounding electrode of the grounding grid, and a high-resistance voltage measurement unit is connected between the working electrode and the reference electrode in the same electrode unit; a zero-resistance current measurement unit is arranged between the two electrode units; the present invention obtains the current intensity between the corresponding two working electrodes measured by the zero-resistance current measurement unit when the electrode self-corrosion potentials measured by the two high-resistance voltage measurement units are different through the corrosion assessment module, and calculates the corresponding macro-battery corrosion rate according to the current intensity; the present invention can accurately detect the corrosion degree of macro-batteries in the power transmission and transformation grounding grid.

Description

Technical Field

[0001] The present invention relates to the technical field of grounding corrosion detection, and in particular to a method, system and equipment for detecting corrosion of macro cells in a power transmission and transformation grounding grid. Background Art

[0002] The corrosion of metals in the soil belongs to electrochemical corrosion in the natural state. The corrosion process has both cathode and anode processes, and the cathode process and the anode process proceed at the same speed. According to the location of the corrosion of the cathode and anode, it can be divided into cathode corrosion process and anode corrosion process. When the two occur in different locations, even far apart, this kind of corrosion is called macro-battery corrosion, also known as macro-battery corrosion. The corrosion potential of metals in soils of different environments is different. If the buried metal is large in size, there will be a potential difference in different parts of the same buried metal in the soil. Driven by this potential difference, macro-battery corrosion is formed.

[0003] The power grounding grid is a large-sized, continuous and well-conducting conductor buried in the earth. The expansion area of ​​the grounding grid of a large substation can even reach several square kilometers, and the radiation length of the small grounding grid of a transmission tower can also reach hundreds of meters. Such a large-sized conductor buried in the soil is prone to macro-cell corrosion, which leads to accelerated corrosion of some conductors of the grounding grid, thereby affecting the service life of the grounding grid. Since the impact of macro-cell corrosion is slow and difficult to predict and measure, this macro-cell corrosion effect usually does not attract the attention of power designers and operators. When macro-cell corrosion occurs, this effect is also difficult to analyze. Therefore, macro-cell corrosion is one of the uncertain factors that reduce the actual service life of the grounding grid.

[0004] The causes of macro cells include concentration cell corrosion, temperature cell corrosion, stress cell corrosion, etc. For power grounding grids, temperature cell and stress cell corrosion are rare. The main cause of macro cell corrosion is concentration cell, including oxygen concentration cell, salt concentration cell, etc. Salt concentration cell mainly occurs in coastal tidal flats or saline-alkali beach areas; oxygen concentration cell is the most common and common. Different soil textures, such as clay and sand, have different gas contents. The grounding electrode surface in them has different oxygen contents, which leads to different self-corrosion potentials. This potential difference will form macro cell corrosion, which increases the corrosion rate of parts with low oxygen content.

[0005] At present, electrochemical three-electrode method, two-electrode method, resistance test strip method and other methods are used to monitor the corrosion of power grounding in soil. However, almost all methods measure the micro-battery corrosion of metals, and there is currently no test method and test equipment for large-scale buried macro-battery corrosion. With the need for refined management in the power field, macro-battery corrosion is one of the important causes of corrosion of grounding materials. It is urgent to establish an accurate macro-battery corrosion detection method for power transmission and transformation grounding grids, and provide engineers with accurate data support during the design, operation and maintenance of power grounding grids to ensure the effective operation of power grounding within the design life and prevent grounding operation accidents. Summary of the invention

[0006] The present invention provides a method, system and device for detecting corrosion of macro cells in a power transmission and transformation grounding grid, which solve the technical problem of how to accurately detect corrosion of macro cells in a power transmission and transformation grounding grid.

[0007] A first aspect of the present invention provides a macro-battery corrosion detection system for a power transmission and transformation grounding grid, wherein a plurality of soil macro-battery corrosion test points are arranged in a soil area where the power transmission and transformation grounding grid is located; the system comprises a test module and a corrosion assessment module;

[0008] The test module includes an electrode unit, a high-resistance voltage measurement unit and a zero-resistance current measurement unit; one electrode unit is respectively arranged on two soil macro-battery corrosion test points; the electrode unit includes a reference electrode and a working electrode of the same material as the grounding electrode of the grounding grid, and a high-resistance voltage measurement unit is connected between the working electrode and the reference electrode in the same electrode unit; the zero-resistance current measurement unit is arranged between the two electrode units;

[0009] The corrosion assessment module is used to obtain the current intensity between the corresponding two working electrodes measured by the zero-resistance current measurement unit when the electrode self-corrosion potentials measured by the two high-resistance voltage measurement units are different, and calculate the corresponding macro-battery corrosion rate based on the current intensity.

[0010] According to an achievable manner of the first aspect of the present invention, the test module further includes a control switch;

[0011] The control switch is arranged between the zero-resistance current measuring unit and any one of the electrode units; when the control switch is turned on, the zero-resistance current measuring unit starts to measure the current intensity between the corresponding two working electrodes.

[0012] According to one achievable manner of the first aspect of the present invention, the control switch is a relay.

[0013] According to one possible implementation of the first aspect of the present invention, the electrode unit further includes an auxiliary stick;

[0014] The auxiliary stick comprises a handle, a stick shaft and a stick tip which are connected in sequence, and the reference electrode and the working electrode are installed on the stick shaft.

[0015] According to one achievable manner of the first aspect of the present invention, the reference electrode and the working electrode are mounted on the stick via a connecting ring.

[0016] According to a possible implementation mode of the first aspect of the present invention, the pole comprises a detachably connected basic pole and an extended connecting pole;

[0017] The length and / or number of the extended connecting rods are set according to the buried depth of the grounding electrodes of the grounding grid.

[0018] According to one possible implementation of the first aspect of the present invention, the corrosion assessment module is specifically used to calculate the corresponding macro cell corrosion rate according to the following formula:

[0019]

[0020] Wherein, γ represents the macrocell corrosion rate, I is the current intensity, and S is the surface area of ​​the working electrode.

[0021] A second aspect of the present invention provides a method for detecting corrosion of macro batteries in a power transmission and transformation grounding grid. The method is based on a system for detecting corrosion of macro batteries in a power transmission and transformation grounding grid as described in any one of the above implementation modes, and the method comprises:

[0022] Obtaining the current intensity between the corresponding two working electrodes measured by the zero-resistance current measurement unit when the electrode self-corrosion potentials measured by the two high-resistance voltage measurement units are different;

[0023] The corresponding macrocell corrosion rate is calculated according to the current intensity.

[0024] A third aspect of the present invention provides a macro-battery corrosion detection device for a power transmission and transformation grounding grid, comprising:

[0025] A memory for storing instructions; wherein the instructions are used to implement the macro-battery corrosion detection method for the power transmission and transformation grounding network as described in the above-described achievable manner;

[0026] A processor is used to execute instructions in the memory.

[0027] A fourth aspect of the present invention is a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for detecting macro-battery corrosion in a power transmission and transformation grounding grid as described in the manner that can be implemented above.

[0028] It can be seen from the above technical solutions that the present invention has the following advantages:

[0029] The system of the present invention comprises a test module and a corrosion assessment module; the test module comprises an electrode unit, a high-resistance voltage measurement unit and a zero-resistance current measurement unit; an electrode unit is respectively arranged at two soil macro-battery corrosion test points; the electrode unit comprises a reference electrode and a working electrode made of the same material as the grounding electrode of the grounding grid, a high-resistance voltage measurement unit is connected between the working electrode and the reference electrode in the same electrode unit; the zero-resistance current measurement unit is arranged between the two electrode units; the present invention obtains the current intensity between the corresponding two working electrodes measured by the zero-resistance current measurement unit when the electrode self-corrosion potentials measured by the two high-resistance voltage measurement units are different through the corrosion assessment module, and calculates the corresponding macro-battery corrosion rate according to the current intensity; the present invention can accurately detect the corrosion degree of the macro-battery of the power transmission and transformation grounding grid, and provide accurate data support for engineers during the design, operation and maintenance of the power grounding grid, so as to ensure the effective operation of the power grounding within the design life and prevent grounding operation accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0031] Figure 1 A structural connection block diagram of a macro-battery corrosion detection system for a power transmission and transformation grounding grid provided by an optional embodiment of the present invention;

[0032] Figure 2 A schematic diagram of the structure of a rod-type electrode provided by an optional embodiment of the present invention;

[0033] Figure 3 A wiring diagram of a test module provided for an optional embodiment of the present invention;

[0034] Figure 4 A flow chart of a method for detecting macro-battery corrosion in a power transmission and transformation grounding grid is provided as an optional embodiment.

[0035] Reference numerals:

[0036] 1-test module; 2-corrosion assessment module; 10-electrode unit; 20-high resistance voltage measurement unit; 30-zero resistance current measurement unit; 40-control switch; 101-reference electrode; 102-working electrode; 103-auxiliary rod; 104-connecting ring; 1031-handle; 1032-rod; 1033-rod tip; 10321-basic rod; 10322-extended connecting rod. DETAILED DESCRIPTION

[0037] The embodiments of the present invention provide a method, system and device for detecting corrosion of macro cells in a power transmission and transformation grounding grid, which are used to solve the technical problem of how to accurately detect corrosion of macro cells in a power transmission and transformation grounding grid.

[0038] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below 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.

[0039] The invention provides a macro-battery corrosion detection system for a power transmission and transformation grounding grid.

[0040] See also Figure 1 , Figure 1 A structural connection block diagram of a macro-battery corrosion detection system for a power transmission and transformation grounding grid provided by an embodiment of the present invention is shown.

[0041] An embodiment of the present invention provides a macro-battery corrosion detection system for a power transmission and transformation grounding grid. A plurality of soil macro-battery corrosion test points are arranged in a soil area where the power transmission and transformation grounding grid is located. The system includes a test module 1 and a corrosion assessment module 2.

[0042] The test module 1 includes an electrode unit 10, a high-resistance voltage measurement unit 20 and a zero-resistance current measurement unit 30; one electrode unit 10 is respectively arranged on two soil macro-battery corrosion test points; the electrode unit 10 includes a reference electrode 101 and a working electrode 102 made of the same material as the grounding electrode of the grounding grid, and a high-resistance voltage measurement unit 20 is connected between the working electrode 102 and the reference electrode 101 in the same electrode unit 10; the zero-resistance current measurement unit 30 is arranged between the two electrode units 10;

[0043] The corrosion assessment module 2 is used to obtain the current intensity between the corresponding two working electrodes 102 measured by the zero-resistance current measurement unit 30 when the electrode self-corrosion potentials measured by the two high-resistance voltage measurement units 20 are different, and calculate the corresponding macro-battery corrosion rate according to the current intensity.

[0044] As a feasible method, the reference electrode 101 may be a high-purity zinc reference electrode 101 . The reference electrode 101 made of this material has high measurement accuracy and is easy to process.

[0045] Among them, the electrode unit 10 placed at a predetermined position can be connected to the high-resistance voltage measurement unit 20 and the zero-resistance current measurement unit 30 through an extended connecting cable, and then the high-resistance voltage measurement unit 20 measures the self-corrosion potential of the electrode, and the zero-resistance current measurement unit 30 measures the connected current intensity after the connection, and the corrosion assessment module 2 calculates the corrosion rate of the soil macro-battery corrosion.

[0046] The main reason for the formation of macro-cells in the soil of the power grounding grid is the concentration cell. The cathode and anode of this concentration cell are large in size, and the rate at which the macro-cell causes corrosion in the anode area is related to the macro-cell current. This is in line with Faraday's law, that is, the corrosion rate is linearly related to the current. Therefore, in this embodiment, the macro-cell corrosion rate is calculated by measuring the macro-cell corrosion current.

[0047] In the embodiment of the present invention, by setting up the test module 1, the measurement of the macro battery current is realized, and the macro battery corrosion rate is calculated based on the corrosion assessment module 2, so as to accurately detect the corrosion degree of the macro battery of the power transmission and transformation grounding network. The detected and calculated data can be applied to the design, operation and maintenance process of the power grounding network to ensure the effective operation of the power grounding within the design life and prevent grounding operation accidents.

[0048] In an embodiment of the present invention, each electrode in the test module 1 needs to be arranged in a soil macro-battery corrosion test point. In order to achieve the measurement of the macro-battery current, the soil macro-battery corrosion test point needs to be set in an area where the soil texture is greatly different. Soil sampling can be carried out in the power grounding grid area by a soil sampler to observe the difference in soil texture at the sampling point. The sampling point includes a horizontal grounding electrode burial area and a vertical grounding electrode burial depth area. Furthermore, based on the soil texture judgment result of the sampling point, the area with a large difference in soil texture is used as a soil macro-battery test point, and the electrode in the electrode unit 10 is placed in the test point in the power grounding grid area.

[0049] The grid grounding electrode is divided into a horizontal grounding electrode and a vertical grounding electrode according to the burial method. When the electrode in the electrode unit 10 is placed at a test point in the power grounding grid area, if the grid grounding electrode to be tested is a horizontal grounding electrode, the depth of the electrode unit 10 in the soil is the burial depth of the horizontal grounding electrode; if the grid grounding electrode to be tested is a vertical grounding electrode, the depth of the electrode unit 10 in the soil is the depth of the vertical grounding electrode.

[0050] In order to facilitate the embedding of the electrode unit 10, in one practicable manner, a rod-type electrode is used as the electrode unit 10. Figure 2 As shown, the rod-type electrode includes an auxiliary rod 103 ; the auxiliary rod 103 includes a handle 1031 , a rod shaft 1032 and a rod tip 1033 connected in sequence, and the reference electrode 101 and the working electrode 102 are mounted on the rod shaft 1032 .

[0051] To facilitate the installation of the reference electrode 101 and the working electrode 102 , in this embodiment, a connecting ring 104 is used to install the reference electrode 101 and the working electrode 102 on the rod 1032 .

[0052] Furthermore, since the depth of the electrode unit 10 into the soil needs to meet the actual depth requirement, in this embodiment, the length of the rod-type electrode is extended by providing an extended connecting rod 10322. Figure 2 As shown, the pole 1032 may include a detachably connected basic pole 10321 and an extended connected pole 10322 .

[0053] The length and / or number of the extended connection rod 10322 are set according to the buried depth of the grounding electrode of the grounding grid. Specifically, by installing an extended connection rod 10322 of a suitable length, the depth of the rod-type electrode penetrating into the soil can meet the corresponding depth requirements. Alternatively, when the extended connection rod 10322 is fixed, multiple extended connection rods 10322 can be installed to make the depth of the rod-type electrode penetrating into the soil meet the corresponding depth requirements. Alternatively, by combining the length and number of the extended connection rod 10322, the depth of the rod-type electrode penetrating into the soil can meet the corresponding depth requirements.

[0054] In the above embodiment of the present invention, by setting the electrode unit 10 as a rod-type electrode, it can be conveniently combined and split into required test electrodes, thereby achieving flexible and rapid installation of the electrode unit 10 according to the buried depth, position, and macro-cell corrosion effect between different depths of the grounding electrode of the power grounding grid.

[0055] The specific wiring diagram of test module 1 is as follows Figure 3 See Figure 3 The test module 1 also includes a control switch 40; the control switch 40 is arranged between the zero-resistance current measurement unit 30 and any one of the electrode units 10; when the control switch 40 is turned on, the zero-resistance current measurement unit 30 starts to measure the current intensity between the corresponding two working electrodes 102.

[0056] It should be noted that the conduction of the control switch 40 may be controlled manually, or the corrosion assessment module 2 may send a control instruction to control the conduction of the control switch 40 .

[0057] As a specific implementation, the control switch 40 is a relay.

[0058] During the specific measurement, after the electrode unit 10 is placed, the relay is in the disconnected state, and the high-resistance voltage measuring unit 20 is used to measure the Figure 3The self-corrosion potential of the working electrode 102 and the reference electrode 101 in the left electrode unit 10, and the self-corrosion potential of the working electrode 102 and the reference electrode 101 in the right electrode unit 10. The self-corrosion potentials on both sides will be different under different soil textures and different oxygen concentrations. It is precisely because of the difference in potential that after being connected to the power grounding grid, these two parts will generate macro-battery current, and an anodic reaction will occur at a location with a lower potential, resulting in an increase in the corrosion rate in this area. After measuring the electrode potentials on both sides, close the relay, use the zero-resistance current measurement unit 30 to measure the current intensity between the two electrodes, and calculate the macro-battery corrosion rate of the electrode by the obtained current intensity.

[0059] As a specific implementation, the zero-resistance current measurement unit 30 includes a zero-resistance ammeter.

[0060] In the above embodiment of the present invention, the structure and wiring method of the test module 1 are simple. Through the test module 1, the required parameters can be quickly and automatically measured to provide the electrode potentials at different positions and the macro-battery current for calculating the macro-battery corrosion rate.

[0061] In one achievable manner, the corrosion assessment module 2 is specifically used to calculate the corresponding macrocell corrosion rate according to the following formula:

[0062]

[0063] In the formula, γ represents the macro-battery corrosion rate, I is the current intensity, and S is the surface area of ​​the working electrode 102.

[0064] In this embodiment, a specific calculation formula for the macro-battery corrosion rate is provided. The formula is obtained based on Faraday's law and can objectively and conveniently obtain the calculated value of the macro-battery corrosion rate.

[0065] It should be noted that the maximum corrosion potential difference and corrosion rate results of the test points can be used as the intensity parameters of the macro-battery corrosion in the grounding grid installation area through multi-point testing of predetermined soil macro-battery test points. When designing the grounding grid, the macro-battery corrosion margin should be included in the design of the grounding electrode corrosion margin. When designing the cathodic protection anti-corrosion scheme for the grounding grid, the areas with more negative potential should be given priority consideration. And when analyzing the corrosion failure of the grounding grid, these parameters can be used as one of the bases for corrosion failure analysis.

[0066] The present invention also provides a method for detecting corrosion of macro batteries in a power transmission and transformation grounding grid. The method is based on the system for detecting corrosion of macro batteries in a power transmission and transformation grounding grid as described in any one of the above embodiments.

[0067] See also Figure 4 , Figure 4 A flow chart of a method for detecting macro-battery corrosion in a power transmission and transformation grounding grid provided by an embodiment of the present invention is shown.

[0068] An embodiment of the present invention provides a method for detecting corrosion of a macro battery in a power transmission and transformation grounding grid, comprising:

[0069] Step S1, obtaining the current intensity between the corresponding two working electrodes 102 measured by the zero-resistance current measurement unit 30 when the electrode self-corrosion potentials measured by the two high-resistance voltage measurement units 20 are different;

[0070] Step S2, calculating the corresponding macro-battery corrosion rate according to the current intensity.

[0071] In one achievable manner, the calculating the corresponding macro-battery corrosion rate according to the current intensity includes:

[0072] The corresponding macrocell corrosion rate is calculated according to the following formula:

[0073]

[0074] In the formula, γ represents the macro-battery corrosion rate, I is the current intensity, and S is the surface area of ​​the working electrode 102.

[0075] The method of the above embodiment of the present invention may be executed by the corrosion assessment module 2 .

[0076] The present invention also provides a macro-battery corrosion detection device for a power transmission and transformation grounding grid, comprising:

[0077] A memory for storing instructions; wherein the instructions are used to implement the macro-battery corrosion detection method for the power transmission and transformation grounding network as described in any one of the above embodiments;

[0078] A processor is used to execute instructions in the memory.

[0079] The present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the method for detecting macro-battery corrosion in a power transmission and transformation grounding grid as described in any one of the above embodiments is implemented.

[0080] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A macro-battery corrosion detection system for power transmission and transformation grounding grid, characterized in that: A plurality of soil macro-cell corrosion test points are arranged in the soil area where the power transmission and transformation grounding grid is located; the system comprises a test module and a corrosion assessment module; The test module includes an electrode unit, a high-resistance voltage measurement unit and a zero-resistance current measurement unit; one electrode unit is respectively arranged on two soil macro-battery corrosion test points; the electrode unit includes a reference electrode and a working electrode of the same material as the grounding electrode of the grounding grid, and a high-resistance voltage measurement unit is connected between the working electrode and the reference electrode in the same electrode unit; the zero-resistance current measurement unit is arranged between the two electrode units; The corrosion assessment module is used to obtain the current intensity between the corresponding two working electrodes measured by the zero-resistance current measurement unit when the electrode self-corrosion potentials measured by the two high-resistance voltage measurement units are different, and calculate the corresponding macro-battery corrosion rate according to the current intensity; The corrosion assessment module is specifically used to calculate the corresponding macro cell corrosion rate according to the following formula: Wherein, γ represents the macrocell corrosion rate, I is the current intensity, and S is the surface area of ​​the working electrode.

2. The power transmission and transformation grounding grid macro cell corrosion detection system according to claim 1 is characterized in that: The test module also includes a control switch; The control switch is arranged between the zero-resistance current measuring unit and any one of the electrode units; when the control switch is turned on, the zero-resistance current measuring unit starts to measure the current intensity between the corresponding two working electrodes.

3. The power transmission and transformation grounding grid macro cell corrosion detection system according to claim 2 is characterized in that: The control switch is a relay.

4. The power transmission and transformation grounding grid macro cell corrosion detection system according to claim 1 is characterized in that: The electrode unit also includes an auxiliary stick; The auxiliary stick comprises a handle, a stick shaft and a stick tip which are connected in sequence, and the reference electrode and the working electrode are installed on the stick shaft.

5. The power transmission and transformation grounding grid macro cell corrosion detection system according to claim 4 is characterized in that: The reference electrode and the working electrode are mounted on the rod through a connecting ring.

6. The power transmission and transformation grounding grid macro cell corrosion detection system according to claim 4 is characterized in that: The stick comprises a detachably connected basic stick and an extended connecting stick; The length and / or number of the extended connecting rods are set according to the buried depth of the grounding electrodes of the grounding grid.

7. A method for detecting macro-battery corrosion in a power transmission and transformation grounding grid, characterized in that: The method is based on the macro-battery corrosion detection system for the power transmission and transformation grounding grid according to any one of claims 1 to 6, and the method comprises: Obtaining the current intensity between the corresponding two working electrodes measured by the zero-resistance current measurement unit when the electrode self-corrosion potentials measured by the two high-resistance voltage measurement units are different; The corresponding macrocell corrosion rate is calculated according to the current intensity.

8. A macro-battery corrosion detection device for power transmission and transformation grounding grid, characterized in that: include: A memory for storing instructions; wherein the instructions are used to implement the macro-battery corrosion detection method for the power transmission and transformation grounding grid according to claim 7; A processor is used to execute instructions in the memory.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by the processor, the method for detecting macro-battery corrosion in the power transmission and transformation grounding grid as claimed in claim 7 is implemented.

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