Coast grounding electrode anti-corrosion method and system and terminal equipment

Abstract

The invention relates to the technical field of high-voltage direct-current power transmission, in particular to a coast grounding electrode anti-corrosion method, a coast grounding electrode anti-corrosion system and terminal equipment. According to the method, the current density distribution uniformity of all the grounding electrode feed rods is analyzed firstly, if the current density distribution exceeds a preset current uniformity threshold value, it is indicated that the current density of part of the grounding electrode feed rods is remarkably higher than that of the other grounding electrode feed rods, and the grounding electrode feed rods with high current density are corroded rapidly; the overall service life and stability of the system are influenced; at the moment, the annual corrosion depth of each grounding electrode feed rod is further predicted, the current of the grounding electrode feed rod with the too high annual corrosion depth is reduced, the borne current amount is dispersed into the other grounding electrode feed rods, and the overall current density distribution uniformity of the system is improved, so that the corrosion rates of all the grounding electrode feed rods are controlled within a reasonable range; therefore, the anti-corrosion performance of the coast direct-current grounding electrode is improved, and the overall service life and the operation stability of all grounding electrode feed rods are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of high-voltage direct current transmission, and in particular to a method, system and terminal equipment for resisting corrosion of a coastal grounding electrode. Background Art

[0002] With the rapid development of high-voltage direct current (HVDC) technology, its importance in long-distance, high-capacity power transmission, offshore wind power grid integration, and asynchronous grid interconnection is becoming increasingly prominent. Currently, the global energy transition is accelerating, with European countries, represented by Germany and the UK, actively planning offshore wind power flexible direct current (HVDC) projects. Simultaneously, emerging markets in Asia, Africa, and Latin America are accelerating their deployment, driven by the demand for grid interconnection and renewable energy transmission.

[0003] Against this backdrop, DC grounding electrodes, as a key component of HVDC transmission systems, face significant challenges in terms of site selection and reliability. A grounding electrode is a conductor or combination of conductors buried in the earth to connect to the ground. As a conductor that maintains close contact with the soil and provides an electrical connection to the earth, it is used to discharge electrical energy from the HVDC transmission system into the earth. Traditional land-based grounding electrodes are limited in economically developed regions and islands due to limited land resources and environmental restrictions. Coastal grounding electrodes, however, have become an important development direction due to their proximity to densely populated areas, low resistivity, and environmental friendliness. However, long-term exposure of coastal grounding electrodes to high-salt, highly alkaline, and highly corrosive seawater environments results in excessively high corrosion rates in the grounding electrode feeder rods, directly impacting system life and stability. Therefore, there is an urgent need to optimize the corrosion resistance of coastal DC grounding electrodes to support the long-term safe operation of future offshore wind power grid integration and intercontinental grid interconnection projects. Summary of the Invention

[0004] The present invention aims to provide a coastal grounding electrode anti-corrosion method, system and terminal equipment to optimize the corrosion resistance of coastal DC grounding electrodes and solve the technical problem that the coastal grounding electrodes are exposed to high-salt, strong alkaline and highly corrosive seawater environments for a long time, resulting in excessive corrosion rate of the grounding electrode feeder rods, which affects the life and stability of the grounding electrodes.

[0005] In order to achieve the above object, the first aspect of the present invention provides a method for anti-corrosion of a coastal ground electrode, which is applicable to a coastal ground electrode, wherein the coastal ground electrode includes a plurality of parallel ground electrode feed rods, and the method includes the following steps:

[0006] Obtaining the current density distribution uniformity of all the ground electrode feeding rods;

[0007] For any of the ground electrode feeder rods, the following anti-corrosion strategy is implemented to ensure that the current density distribution uniformity meets the preset current uniformity threshold:

[0008] Obtaining a feeder rod current of the ground electrode feeder rod, and then predicting an annual corrosion depth of the ground electrode feeder rod based on the feeder rod current;

[0009] If the annual corrosion depth exceeds a preset depth threshold, the current of the feed rod is controlled to decrease until the annual corrosion depth meets the depth threshold.

[0010] The above-mentioned coastal ground electrode anti-corrosion method takes into account that there are several ground electrode feeder rods in the coastal ground electrode, the current of each ground electrode feeder rod affects each other, and the current of each ground electrode feeder rod affects its own corrosion rate. The present invention first analyzes the current density distribution uniformity of all the ground electrode feeder rods. If the current density distribution exceeds the preset current uniformity threshold, it means that the current density of some ground electrode feeder rods is significantly higher than that of the other ground electrode feeder rods, resulting in rapid corrosion of the ground electrode feeder rods with high current density, affecting the overall life and stability of the system; at this time, the annual corrosion depth of each ground electrode feeder rod is further predicted, and the current of the ground electrode feeder rod with too high annual corrosion depth is reduced, and the current it bears is dispersed to the other ground electrode feeder rods, thereby improving the overall current density distribution uniformity of the system, thereby controlling the corrosion rate of all ground electrode feeder rods within a reasonable range, thereby improving the corrosion resistance of the coastal DC ground electrode, and further improving the overall life and operational stability of all ground electrode feeder rods.

[0011] It should be understood that if the overall current density distribution uniformity of all grounding electrode feeder rods is not taken into consideration, and the current of one grounding electrode feeder rod is simply controlled to decrease when the corrosion rate of the grounding electrode feeder rod is detected to be too fast, then the corrosion rate of some of the remaining grounding electrode feeder rods in the same coastal grounding electrode system may become too high after receiving the dispersed current, resulting in the overall current density distribution of all grounding electrode feeder rods still being uneven, and the overall life and stability of the coastal grounding electrode system cannot be improved.

[0012] Furthermore, obtaining the current density distribution uniformity of all the ground electrode feeding rods includes:

[0013] Acquire the temperature of each ground electrode feeding rod, and then acquire the mean square deviation of the temperatures of all the ground electrode feeding rods based on the temperature of each ground electrode feeding rod;

[0014] The current density distribution uniformity is analyzed based on the temperature mean square error.

[0015] In this implementation, the current density of each feed rod is reflected by the temperature of each feed rod, and the current density distribution of each feed rod is reflected by the mean square difference of the temperatures of each feed rod. Compared with directly measuring the current density-related parameters of the ground electrode feed rod, on the one hand, it is easier to directly deploy temperature sensors to obtain the temperature of the ground electrode feed rod, which can reduce the complexity and cost of coastal ground electrode corrosion resistance control; on the other hand, according to Joule's law, the Joule heat generated by the current is proportional to the square of the current, that is, the temperature change has an amplifying effect on the current change. Therefore, the temperature change of the ground electrode feed rod can more significantly reflect its current density change, and the mean square difference of the temperatures between the ground electrode feed rods can amplify the tiny current density distribution differences between the ground electrode feed rods, thereby improving the accuracy of the current density distribution uniformity analysis, which is conducive to accurately adjusting and controlling the current flowing through each ground electrode feed rod, thereby accurately controlling the corrosion rate of all ground electrode feed rods within a reasonable range, and improving the corrosion resistance of the coastal DC ground electrode.

[0016] Furthermore, the obtaining of the feeder rod current of the ground electrode feeder rod and then predicting the annual corrosion depth of the ground electrode feeder rod based on the feeder rod current includes:

[0017] The corrosion rate of the ground electrode feeder rod is obtained based on the feeder rod current, and its expression is as follows:

[0018]

[0019] Wherein, vi represents the corrosion rate of the i-th ground electrode feed rod, Ii represents the feed rod current of the i-th ground electrode feed rod, M represents the molar mass of the ground electrode feed rod, n represents the metal valence of the ground electrode feed rod, and S represents the surface area of ​​the ground electrode feed rod;

[0020] The annual corrosion depth is predicted based on the corrosion rate.

[0021] Furthermore, the expression for predicting the annual corrosion depth based on the corrosion rate is as follows:

[0022]

[0023] Wherein, di represents the annual corrosion depth of the i-th ground electrode feeder rod, v represents the corrosion rate, ρ represents the density of the ground electrode feeder rod, Ii represents the feeder rod current of the i-th ground electrode feeder rod, M represents the molar mass of the ground electrode feeder rod, n represents the metal valence of the ground electrode feeder rod, and S represents the surface area of ​​the ground electrode feeder rod.

[0024] In this implementation, a mathematical model quantifying the relationship between corrosion rate and feeder rod current is established to accurately and dynamically predict the corrosion process of the ground electrode feeder rod. This formula comprehensively considers the electrical parameters, material properties, and structural dimensions of the collector feeder rod. The annual corrosion depth of the ground electrode feeder rod is used to quantify the corrosion rate of the ground electrode feeder rod. This provides a direct basis for subsequently determining whether the ground electrode feeder rod is corroding too rapidly, optimizes the corrosion control process of this ground electrode anti-corrosion method, and improves the accuracy of ground electrode feeder rod corrosion monitoring.

[0025] A second aspect of the present invention provides a coastal ground electrode anti-corrosion system, which includes a main control module, a DC current generator, a current distribution monitor, a current measurement box, and a plurality of feed rod modules, each of which is provided with a ground electrode feed rod and a sliding rheostat; wherein:

[0026] The DC current generator is used to transmit the current of the external high-voltage DC transmission network to the plurality of feed rod modules;

[0027] Several of the feed rod modules are connected in parallel with each other; in any of the feed rod modules, the ground electrode feed rod is used to disperse the current input by the DC current generator to the ground through the sliding rheostat;

[0028] The current distribution monitor is used to obtain the current density distribution uniformity of all the ground electrode feeder rods;

[0029] The main control module is used to execute the following anti-corrosion strategy for any of the ground electrode feed rods so that the current density distribution uniformity meets a preset current uniformity threshold:

[0030] Obtaining the feeder rod current of the ground electrode feeder rod through the current measurement box, and then predicting the annual corrosion depth of the ground electrode feeder rod based on the feeder rod current;

[0031] If the annual corrosion depth exceeds a preset depth threshold, the current of the feeding rod is controlled to decrease by adjusting the resistance of the sliding rheostat until the annual corrosion depth meets the depth threshold.

[0032] The above-mentioned coastal ground electrode anti-corrosion system first analyzes the current density distribution uniformity of all the ground electrode feed rods. If the current density distribution exceeds the preset current uniformity threshold, it means that the current density of some ground electrode feed rods is significantly higher than that of the other ground electrode feed rods, resulting in rapid corrosion of the ground electrode feed rods with high current density, affecting the overall life and stability of the system; at this time, the annual corrosion depth of each ground electrode feed rod is further predicted, and the current of the ground electrode feed rod with an excessively high annual corrosion depth is reduced, and the current it bears is dispersed to the other ground electrode feed rods, thereby improving the overall current density distribution uniformity of the system, thereby controlling the corrosion rate of all ground electrode feed rods within a reasonable range, thereby improving the corrosion resistance of the coastal DC ground electrode, and further improving the overall life and operational stability of all ground electrode feed rods.

[0033] It should be noted that the present invention connects a sliding rheostat in series to each ground electrode feed rod, so that the ground electrode feed rod is connected to the high-voltage DC transmission network through the sliding rheostat, and then the current flowing into the corresponding ground electrode feed rod is controlled by adjusting the resistance value of the sliding rheostat. Specifically, when the resistance value of the sliding rheostat is adjusted to increase, the current flowing into the corresponding ground electrode feed rod decreases, and the current is dispersed to the remaining ground electrode feed rods in the ground electrode system.

[0034] Furthermore, any of the feed rod modules includes a drainage cable, a grounding electrode well wall, a cable support and protection pipe, backfill sand and coke; wherein:

[0035] The bottom end of the grounding electrode well protective wall is filled with the coke;

[0036] The ground electrode feed rod is wrapped around the center of the coke; the ground electrode feed rod is electrically connected to the DC current generator through the drainage cable and the sliding rheostat; the ground electrode feed rod is used to disperse the current input by the DC current generator to the ground through the sliding rheostat;

[0037] The cable support and protection tube is provided inside the grounding electrode well protective wall, and is used to support and protect the drainage cable;

[0038] The drainage cable is laid along the cable support protection tube from the DC current generator to the ground electrode feed rod;

[0039] The inner side of the grounding electrode well protective wall is filled with the backfill sand and gravel, and the backfill sand and gravel wrap the drainage cable and the cable support protection tube.

[0040] Furthermore, any of the feed rod modules includes a temperature sensor and a temperature measuring optical cable; the temperature sensor is provided on the surface of the ground electrode feed rod; the temperature measuring optical cable is laid along the cable support protection tube from the current distribution monitor to the temperature sensor; the temperature sensor is electrically connected to the current distribution monitor through the temperature measuring optical cable; wherein:

[0041] The current distribution monitor is used to obtain the temperature of the corresponding ground electrode feed rod through the temperature sensor, thereby obtaining the temperature mean square deviation of all the ground electrode feed rods based on the temperature of each ground electrode feed rod, and then analyzing the current density distribution uniformity based on the temperature mean square deviation.

[0042] Furthermore, for any of the feeder rod modules, a current measurement terminal is included, and the current measurement terminal is used to obtain the feeder rod current of the ground electrode feeder rod through the drainage cable and feed the feeder rod current back to the current measurement box; for the main control module, the feeder rod current of the ground electrode feeder rod is obtained through the current measurement box, and then the annual corrosion depth of the ground electrode feeder rod is predicted based on the feeder rod current, including:

[0043] The corrosion rate of the ground electrode feeder rod is obtained based on the feeder rod current, and its expression is as follows:

[0044]

[0045] Wherein, vi represents the corrosion rate of the i-th ground electrode feed rod, Ii represents the feed rod current of the i-th ground electrode feed rod, M represents the molar mass of the ground electrode feed rod, n represents the metal valence of the ground electrode feed rod, and S represents the surface area of ​​the ground electrode feed rod;

[0046] The annual corrosion depth is predicted based on the corrosion rate.

[0047] Furthermore, the expression for predicting the annual corrosion depth based on the corrosion rate is as follows:

[0048]

[0049] Wherein, di represents the annual corrosion depth of the i-th ground electrode feeder rod, v represents the corrosion rate, ρ represents the density of the ground electrode feeder rod, Ii represents the feeder rod current of the i-th ground electrode feeder rod, M represents the molar mass of the ground electrode feeder rod, n represents the metal valence of the ground electrode feeder rod, and S represents the surface area of ​​the ground electrode feeder rod.

[0050] A third aspect of the present invention provides a terminal device, comprising a processor and a memory, wherein:

[0051] The memory is used to store program code and transmit the program code to the processor;

[0052] The processor is used to execute the coastal ground electrode anti-corrosion method as described in any one of the first aspects of the present invention according to the instructions in the program code. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 This is a schematic flow chart of a coastal ground electrode corrosion resistance method provided by an embodiment of the present invention;

[0054] Figure 2 This is a partial structural diagram of a coastal grounding electrode anti-corrosion system provided by an embodiment of the present invention;

[0055] Figure 3 This is a partial structural diagram of another coastal grounding electrode anti-corrosion system provided by an embodiment of the present invention;

[0056] Among them: 1. Current distribution monitor; 2. Temperature measurement optical cable; 3. Temperature sensor; 4. Current measurement box; 5. Current measurement terminal; 6. Communication cable; 7. Feed rod module; 701. Grounding electrode feed rod; 702. Grounding electrode well wall; 703. Cable support and protection tube; 704. Backfill sand and gravel; 705. Coke; 8. DC current generator; 9. Drainage cable; 10. Sliding rheostat. DETAILED DESCRIPTION

[0057] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments. It should be noted that the following detailed descriptions are all exemplary descriptions and are intended to provide further detailed descriptions of the present invention. Unless otherwise defined, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art to which this application belongs; the terms used herein in the specification of the application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the description of the above-mentioned drawings, as well as any variations thereof, are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order.

[0058] It should be understood that although the steps in the flowcharts of the accompanying drawings are shown in sequence as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some of the steps in the flowcharts of the accompanying drawings may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0059] Before describing the present application in detail with reference to the accompanying drawings and in combination with the embodiments, the technical background involved in the present application will first be described.

[0060] With the rapid development of high-voltage direct current (HVDC) technology, its importance in long-distance, high-capacity power transmission, offshore wind power grid integration, and asynchronous grid interconnection is becoming increasingly prominent. Currently, the global energy transition is accelerating, with European countries, represented by Germany and the UK, actively planning offshore wind power flexible direct current (HVDC) projects. Simultaneously, emerging markets in Asia, Africa, and Latin America are accelerating their deployment, driven by the demand for grid interconnection and renewable energy transmission.

[0061] Against this backdrop, DC grounding electrodes, as a key component of HVDC transmission systems, face significant challenges in terms of site selection and reliability. A grounding electrode is a conductor or combination of conductors buried in the earth to connect to the ground. As a conductor that maintains close contact with the soil and provides an electrical connection to the earth, it is used to discharge electrical energy from the HVDC transmission system into the earth. Traditional land-based grounding electrodes are limited in economically developed regions and islands due to limited land resources and environmental restrictions. Coastal grounding electrodes, however, have become an important development direction due to their proximity to densely populated areas, low resistivity, and environmental friendliness. However, long-term exposure of coastal grounding electrodes to high-salt, highly alkaline, and highly corrosive seawater environments results in excessively high corrosion rates in the grounding electrode feeder rods, directly impacting system life and stability. Therefore, there is an urgent need to optimize the corrosion resistance of coastal DC grounding electrodes to support the long-term safe operation of future offshore wind power grid integration and intercontinental grid interconnection projects.

[0062] In order to solve the above technical problems, refer to Figure 1 and Figure 3 The first embodiment of the present invention provides a method for anti-corrosion of a coastal ground electrode, which is applicable to a coastal ground electrode. The coastal ground electrode includes a plurality of parallel ground electrode feed rods 701. The method includes the following steps:

[0063] S1. Obtaining the current density distribution uniformity of all the ground electrode feeding rods;

[0064] S2. For any of the ground electrode feeder rods, execute the following anti-corrosion strategy to ensure that the current density distribution uniformity meets a preset current uniformity threshold:

[0065] S21, obtaining a feeder rod current of the ground electrode feeder rod, and then predicting an annual corrosion depth of the ground electrode feeder rod based on the feeder rod current;

[0066] S22. If the annual corrosion depth exceeds a preset depth threshold, control the current of the feed rod to decrease until the annual corrosion depth meets the depth threshold.

[0067] The above-mentioned coastal ground electrode anti-corrosion method takes into account that there are several ground electrode feed rods 701 in the coastal ground electrode, the current of each ground electrode feed rod 701 affects each other, and the current of each ground electrode feed rod 701 affects its own corrosion rate. The present invention first analyzes the uniformity of the current density distribution of all the ground electrode feed rods 701. If the current density distribution exceeds the preset current uniformity threshold, it means that the current density of some ground electrode feed rods 701 is significantly higher than that of the other ground electrode feed rods 701, resulting in the high current density ground electrode feed rods 701. The rod 701 corrodes rapidly, affecting the overall life and stability of the system. In this case, the annual corrosion depth of each ground electrode feeder rod 701 is further predicted, and the current of the ground electrode feeder rod 701 with excessively high annual corrosion depth is reduced. The current borne by the ground electrode feeder rod 701 is distributed to the remaining ground electrode feeder rods 701, improving the uniformity of the overall current density distribution of the system. The corrosion rate of all ground electrode feeder rods 701 is controlled within a reasonable range, thereby improving the corrosion resistance of the coastal DC ground electrode and further improving the overall life and operational stability of all ground electrode feeder rods 701.

[0068] It should be understood that if the overall current density distribution uniformity of all ground electrode feed rods 701 is not taken into consideration, and the current of one ground electrode feed rod 701 is simply controlled to decrease when the corrosion rate of the ground electrode feed rod 701 is detected to be too fast, then the corrosion rate of the remaining ground electrode feed rods 701 in the same coastal ground electrode system may become too high after receiving the dispersed current, resulting in the overall current density distribution of all ground electrode feed rods 701 still being uneven, and the overall life and stability of the coastal ground electrode system cannot be improved.

[0069] Furthermore, obtaining the current density distribution uniformity of all the ground electrode feeding rods 701 includes:

[0070] Acquire the temperature of each ground electrode feeding rod 701, and then acquire the mean square deviation of the temperatures of all the ground electrode feeding rods 701 based on the temperature of each ground electrode feeding rod 701;

[0071] The current density distribution uniformity is analyzed based on the temperature mean square error.

[0072] Specifically, the calculation expression for obtaining the mean square deviation of the temperatures of all the grounding electrode feeder rods 701 based on the temperature of each grounding electrode feeder rod 701 is as follows:

[0073]

[0074] where C i represents the temperature of the i-th grounding electrode feeder rod 701, and k represents the total number of grounding electrode feeder rods 701 in the coastal grounding electrode.

[0075] When the mean square deviation of temperature 0 < A < 0.5, the temperature difference between the grounding electrode feeder rods 701 on the surface is small, and the temperature distribution among all the grounding electrode feeder rods 701 is relatively uniform, reflecting that the current density distribution of all the grounding electrode feeder rods 701 is uniform, and no anti-corrosion regulation is required. When the mean square deviation of temperature 0.5 ≤ A, the temperature difference between the grounding electrode feeder rods 701 on the surface is large, and the temperature distribution among all the grounding electrode feeder rods 701 is non-uniform, reflecting that the current density distribution of all the grounding electrode feeder rods 701 is non-uniform, and the corrosion rate of some feeder rods is too high. It is necessary to adjust the current of the grounding electrode feeder rods 701 whose annual corrosion depth exceeds the preset depth threshold to improve the overall life and operation stability of the coastal grounding electrode.

[0076] In this embodiment, the current density of each feeder rod is reflected by the temperature of each feeder rod, and then the current density distribution of each feeder rod is reflected by the mean square deviation of the temperatures of each feeder rod. Compared with directly measuring the current density-related parameters of the grounding electrode feeder rod 701, on the one hand, directly arranging the temperature sensor 3 to obtain the temperature of the grounding electrode feeder rod 701 is easier to implement, which can reduce the complexity and cost of anti-corrosion regulation of the coastal grounding electrode; on the other hand, according to Joule's law, the Joule heat generated by the current is proportional to the square of the current, that is, the temperature change has an amplification effect on the current change. Therefore, the temperature change of the grounding electrode feeder rod 701 can more significantly reflect its current density change, and the mean square deviation value of the temperatures between the grounding electrode feeder rods 701 can amplify the small current density distribution differences between the grounding electrode feeder rods 701, thereby improving the accuracy of the analysis of the current density distribution uniformity, which is beneficial to accurately adjusting and controlling the current flowing through each grounding electrode feeder rod 701, so as to accurately control the corrosion rate of all the grounding electrode feeder rods 701 within a reasonable range and improve the anti-corrosion performance of the coastal DC grounding electrode.

[0077] Further, obtaining the feeder rod current of the grounding electrode feeder rod 701 and then predicting the annual corrosion depth of the grounding electrode feeder rod 701 based on the feeder rod current includes:

[0078] Obtaining the corrosion rate of the grounding electrode feeder rod 701 based on the feeder rod current, and its expression is as follows:

[0079]

[0080] Among them, v i The corrosion rate of the i-th ground electrode feed rod 701 is expressed in g / (m 2 h), I i represents the current of the i-th ground electrode feed rod 701, in A, M represents the molar mass of the ground electrode feed rod 701, n represents the metal valence of the ground electrode feed rod 701, S represents the surface area of ​​the ground electrode feed rod 701, in mm 2 ;

[0081] The annual corrosion depth is predicted based on the corrosion rate.

[0082] Furthermore, the expression for predicting the annual corrosion depth based on the corrosion rate is as follows:

[0083]

[0084] Among them, d i represents the annual corrosion depth of the i-th ground electrode feeder rod 701, in mm / a, and v represents the corrosion rate, in g / (m 2 h), ρ represents the density of the ground electrode feed rod 701, and the unit is g / cm 2 , I i represents the current of the i-th ground electrode feed rod 701, in A, M represents the molar mass of the ground electrode feed rod 701, n represents the metal valence of the ground electrode feed rod 701, S represents the surface area of ​​the ground electrode feed rod 701, in mm 2 .

[0085] Specifically, when the maximum annual corrosion depth d of any of the ground electrode feeder rods 701 is i(max) >d′ / 40, indicating that the annual corrosion depth exceeds the preset depth threshold, where d′ represents the thickness of the ground electrode feed rod 701. The preset depth threshold d′ / 40 indicates that the preset service life of the ground electrode feed rod 701 is 40 years.

[0086] In this embodiment, by establishing a mathematical model for the quantitative relationship between corrosion rate and feeder rod current, accurate dynamic prediction of the corrosion process of the ground electrode feeder rod 701 is achieved. The above formula comprehensively considers the electrical parameters, material properties, and structural dimensions of the collector feeder rod. The annual corrosion depth of the ground electrode feeder rod 701 is used to quantitatively reflect the corrosion rate of the ground electrode feeder rod 701. This provides a direct basis for subsequently determining whether the ground electrode feeder rod 701 is corroding too quickly. This optimizes the corrosion control process of this ground electrode anti-corrosion method and improves the corrosion monitoring accuracy of the ground electrode feeder rod 701.

[0087] See also Figure 2 and Figure 3 The second embodiment of the present invention provides a coastal ground electrode anti-corrosion system, which includes a main control module, a DC current generator 8, a current distribution monitor 1, a current measurement box 4, and a plurality of feed rod modules 7, each of which is provided with a ground electrode feed rod 701 and a sliding rheostat 10; wherein:

[0088] The DC current generator 8 is used to transmit the current of the external high-voltage DC transmission network to the plurality of feed rod modules 7;

[0089] Several of the feed rod modules 7 are connected in parallel with each other; in any of the feed rod modules 7, the ground electrode feed rod 701 is used to disperse the current input by the DC current generator 8 to the ground through the sliding rheostat 10;

[0090] The current distribution monitor 1 is used to obtain the current density distribution uniformity of all the ground electrode feeding rods 701;

[0091] The main control module is used to execute the following anti-corrosion strategy for any of the ground electrode feeding rods 701 so that the current density distribution uniformity meets a preset current uniformity threshold:

[0092] Obtaining the feed rod current of the ground electrode feed rod 701 through the current measurement box 4, and then predicting the annual corrosion depth of the ground electrode feed rod 701 based on the feed rod current;

[0093] If the annual corrosion depth exceeds a preset depth threshold, the current of the feeding rod is controlled to decrease by adjusting the resistance of the sliding rheostat until the annual corrosion depth meets the depth threshold.

[0094] The above-mentioned coastal ground electrode anti-corrosion system first analyzes the current density distribution uniformity of all the ground electrode feed rods 701. If the current density distribution exceeds a preset current uniformity threshold, it means that the current density of some ground electrode feed rods 701 is significantly higher than that of the remaining ground electrode feed rods 701, resulting in rapid corrosion of the ground electrode feed rods 701 with high current density, affecting the overall life and stability of the system. At this time, the annual corrosion depth of each ground electrode feed rod 701 is further predicted, and the current of the ground electrode feed rod 701 with excessively high annual corrosion depth is reduced, distributing the current borne by the ground electrode feed rod to the remaining ground electrode feed rods 701, thereby improving the overall current density distribution uniformity of the system, thereby controlling the corrosion rate of all ground electrode feed rods 701 within a reasonable range, thereby improving the corrosion resistance of the coastal DC ground electrode, and further improving the overall life and operational stability of all ground electrode feed rods 701.

[0095] It should be noted that the present invention connects a sliding rheostat 10 in series to each ground electrode feed rod 701, so that the ground electrode feed rod 701 is connected to the high-voltage direct current transmission network through the sliding rheostat 10, and then controls the current flowing into the corresponding ground electrode feed rod 701 by adjusting the resistance value of the sliding rheostat 10. Specifically, when the resistance value of the sliding rheostat 10 is increased, the current flowing into the corresponding ground electrode feed rod 701 decreases, and the current is dispersed to the remaining ground electrode feed rods 701 in the ground electrode system.

[0096] refer to Figure 3 , further, for any of the feed rod modules 7, including drainage cables 9, grounding electrode well wall 702, cable support and protection tube 703, backfill sand and gravel 704 and coke 705; wherein:

[0097] The bottom end of the grounding electrode well protective wall 702 is filled with the coke 705;

[0098] The ground electrode feed rod 701 is wrapped around the center of the coke 705; the ground electrode feed rod 701 is electrically connected to the DC current generator 8 through the drainage cable 9 and the sliding rheostat 10; the ground electrode feed rod 701 is used to disperse the current input by the DC current generator 8 to the ground through the sliding rheostat 10;

[0099] The cable support and protection tube 703 is provided inside the grounding electrode well protective wall 702, which is used to support and protect the drainage cable 9;

[0100] The drainage cable 9 is laid along the cable support protection tube 703 from the DC current generator 8 to the ground electrode feeding rod 701;

[0101] The inner side of the grounding electrode well protective wall 702 is filled with the backfill sand and gravel 704 , and the backfill sand and gravel 704 wraps the drainage cable 9 and the cable support protection tube 703 .

[0102] In a possible embodiment, the drainage cable 9 can sample corrosion-resistant copper core cables to improve monitoring accuracy; the grounding electrode well protective wall 702 can maintain the stability of the grounding electrode deep well structure, prevent the collapse of the soft soil layer on the coast, ensure that the coke 705 is isolated from the soil, and reduce the penetration and corrosion of the grounding electrode feed rod 701 by soil salt; the cable support protection tube 703 can fix the drainage cable 9 and prevent it from falling off and causing mechanical damage; the backfill sand and gravel 704 covers the coke 705, which can stabilize the well structure of the grounding electrode, balance the resistivity in the well and prevent rainwater from eroding the drainage cable 9 and the grounding electrode feed rod 701; the coke 705 is filled around the grounding electrode feed rod 701 to form a current leakage channel and isolate the grounding electrode feed rod 701 from the coastal soil.

[0103] refer to Figure 3 Furthermore, any of the feed rod modules 7 includes a temperature sensor 3 and a temperature measuring optical cable 2; the temperature sensor 3 is provided on the surface of the ground electrode feed rod 701; the temperature measuring optical cable 2 is laid along the cable support and protection tube 703 from the current distribution monitor 1 to the temperature sensor 3; the temperature sensor 3 is electrically connected to the current distribution monitor 1 through the temperature measuring optical cable 2; wherein:

[0104] The current distribution monitor 1 is used to obtain the temperature of the corresponding ground electrode feed rod 701 through the temperature sensor 3, thereby obtaining the temperature mean square deviation of all the ground electrode feed rods 701 based on the temperature of each ground electrode feed rod 701, and then analyzing the uniformity of the current density distribution based on the temperature mean square deviation.

[0105] In this embodiment, the temperature sensor 3 is directly installed on the surface of the grounding electrode feed rod 701 to monitor its temperature in real time; the temperature measuring optical cable 2 is laid along the cable support and protection tube 703 to the inside of the grounding electrode deep well formed by the grounding electrode well protective wall 702, and transmits the temperature sensor 3 signal to the ground current distribution monitor 1; the current distribution monitor 1 collects and analyzes the data from the temperature sensor 3 in real time, and then analyzes the uniformity of the current density distribution through the temperature mean square error of all grounding electrode feed rods 701; the cable support and protection tube 703 can fix the temperature measuring optical cable 2 and prevent it from falling off and causing mechanical damage.

[0106] Specifically, the calculation expression for obtaining the mean square deviation of the temperatures of all the ground electrode feeding rods 701 based on the temperature of each ground electrode feeding rod 701 is as follows:

[0107]

[0108] Among them, C irepresents the temperature of the \(i\)-th grounding electrode feeder rod 701, and \(k\) represents the total number of grounding electrode feeder rods 701 in the coastal grounding electrode.

[0109] When the temperature standard deviation \(0 < A < 0.5\), the temperature difference between the surface grounding electrode feeder rods 701 is small, and the temperature distribution among all the grounding electrode feeder rods 701 is relatively uniform, indicating that the current density distribution of all the grounding electrode feeder rods 701 is uniform, and anti-corrosion regulation is not required. When the temperature standard deviation \(0.5\leq A\), the temperature difference between the surface grounding electrode feeder rods 701 is large, and the temperature distribution among all the grounding electrode feeder rods 701 is non-uniform, indicating that the current density distribution of all the grounding electrode feeder rods 701 is non-uniform, and the corrosion rate of some feeder rods is too high. It is necessary to adjust the current of the grounding electrode feeder rod 701 whose annual corrosion depth exceeds the preset depth threshold to improve the overall life and operating stability of the coastal grounding electrode.

[0110] Reference Figure 3 Furthermore, for any of the said feeder rod modules 7, it includes a current measurement terminal 5 and a communication cable 6. The current measurement terminal 5 is used to obtain the feeder rod current of the grounding electrode feeder rod 701 through the diversion cable 9 and feedback the feeder rod current to the current measurement box 4 through the communication cable 6; for the main control module, obtaining the feeder rod current of the grounding electrode feeder rod 701 through the current measurement box 4, and then predicting the annual corrosion depth of the grounding electrode feeder rod 701 based on the feeder rod current includes:

[0111] Obtaining the corrosion rate of the grounding electrode feeder rod 701 based on the feeder rod current, and its expression is as follows:

[0112]

[0113] where \(v\) i represents the corrosion rate of the \(i\)-th grounding electrode feeder rod 701, with the unit of g / (m 2 h), \(I\) i represents the feeder rod current of the \(i\)-th grounding electrode feeder rod 701, with the unit of A, \(M\) represents the molar mass of the grounding electrode feeder rod 701, \(n\) represents the metal valence of the grounding electrode feeder rod 701, \(S\) represents the surface area of the grounding electrode feeder rod 701, with the unit of mm 2 ;

[0114] Predicting the annual corrosion depth based on the corrosion rate.

[0115] Furthermore, the expression for predicting the annual corrosion depth based on the corrosion rate is as follows:

[0116]

[0117] where \(d\)i represents the annual corrosion depth of the i-th ground electrode feeder rod 701, in mm / a, and v represents the corrosion rate, in g / (m 2 h), ρ represents the density of the ground electrode feed rod 701, and the unit is g / cm 2 , I i represents the current of the i-th ground electrode feed rod 701, in A, M represents the molar mass of the ground electrode feed rod 701, n represents the metal valence of the ground electrode feed rod 701, S represents the surface area of ​​the ground electrode feed rod 701, in mm 2 .

[0118] Specifically, when the maximum annual corrosion depth d of any of the ground electrode feeder rods 701 is i(max) >d′ / 40, indicating that the annual corrosion depth exceeds the preset depth threshold, where d′ represents the thickness of the ground electrode feed rod 701. The preset depth threshold d′ / 40 indicates that the preset service life of the ground electrode feed rod 701 is 40 years.

[0119] In this embodiment, the current measurement terminal 5 is connected in series between the drainage cable 9 and the DC current generator 8 to directly measure the ground current value; the current measurement box 4 integrates data conversion and temporary storage functions, converts the current signal collected by the current measurement terminal 5 into a digital signal, and transmits it to the main control module.

[0120] A third embodiment of the present invention provides a terminal device, comprising a processor and a memory, wherein:

[0121] The memory is used to store program code and transmit the program code to the processor;

[0122] The processor is used to execute the coastal ground electrode anti-corrosion method as described in any one of the first aspects of the present invention according to the instructions in the program code.

[0123] The coastal grounding electrode anti-corrosion method, system, and terminal device provided by the present invention have at least the following advantages over the prior art:

[0124] The present invention takes into account that there are several ground electrode feeder rods 701 in the coastal ground electrode, and the current of each ground electrode feeder rod 701 affects each other, and the current of each ground electrode feeder rod 701 affects its own corrosion rate. By building an experimental platform for the coastal ground electrode, the feeder rod temperature and current distribution of each electrode are obtained, and the annual corrosion depth of each ground electrode feeder rod 701 is further predicted. The feeder rod is analyzed to determine whether it can meet the service life requirements. The sliding resistor is negatively feedback-regulated to reduce the current of the ground electrode feeder rod 701 with an excessively high annual corrosion depth, and the current borne by the ground electrode feeder rod is distributed to the remaining ground electrode feeder rods 701. This improves the current distribution of all ground electrode feeder rods 701 and improves the uniformity of the current density distribution of the entire system, thereby controlling the corrosion rate of all ground electrode feeder rods 701 within a reasonable range, reducing the overall corrosion amount of the ground electrode feeder rods 701, and controlling the corrosion life of all ground electrode feeder rods 701 within a reasonable range, thereby improving the corrosion resistance of the coastal DC ground electrode and further improving the overall life and operational stability of all ground electrode feeder rods 701.

[0125] It should be understood that if the overall current density distribution uniformity of all ground electrode feed rods 701 is not taken into consideration, and the current of one ground electrode feed rod 701 is simply controlled to decrease when the corrosion rate of the ground electrode feed rod 701 is detected to be too fast, then the corrosion rate of the remaining ground electrode feed rods 701 in the same coastal ground electrode system may become too high after receiving the dispersed current, resulting in the overall current density distribution of all ground electrode feed rods 701 still being uneven, and the overall life and stability of the coastal ground electrode system cannot be improved.

[0126] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, database or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory may include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchains. The processor involved in the various embodiments provided herein may be, but are not limited to, a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic unit, a data processing logic unit based on quantum computing, and the like.

[0127] The "embodiment" mentioned in this document means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments. In order to make the description concise, not all possible combinations of the various technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0128] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make several improvements and substitutions without departing from the scope of the present application, and such improvements and substitutions should also be considered within the scope of protection of the present invention. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A method for anti-corrosion of a coastal grounding electrode, characterized in that: Applicable to a coast ground electrode, the coast ground electrode comprising a plurality of parallel-connected ground electrode feeder rods, the method comprising the following steps: Obtaining the current density distribution uniformity of all the ground electrode feeding rods; For any of the ground electrode feeder rods, the following anti-corrosion strategy is implemented to ensure that the current density distribution uniformity meets the preset current uniformity threshold: Obtaining a feeder rod current of the ground electrode feeder rod, and then predicting an annual corrosion depth of the ground electrode feeder rod based on the feeder rod current; If the annual corrosion depth exceeds a preset depth threshold, the current of the feed rod is controlled to decrease until the annual corrosion depth meets the depth threshold.

2. A coastal ground electrode anti-corrosion method according to claim 1, characterized in that: The obtaining of the current density distribution uniformity of all the ground electrode feed rods includes: Acquire the temperature of each ground electrode feeding rod, and then acquire the mean square deviation of the temperatures of all the ground electrode feeding rods based on the temperature of each ground electrode feeding rod; The current density distribution uniformity is analyzed based on the temperature mean square error.

3. The method for anti-corrosion of a coastal ground electrode according to claim 1, characterized in that: The obtaining of the feeder rod current of the ground electrode feeder rod and then predicting the annual corrosion depth of the ground electrode feeder rod based on the feeder rod current includes: The corrosion rate of the ground electrode feeder rod is obtained based on the feeder rod current, and its expression is as follows: Among them, v i represents the corrosion rate of the i-th grounding electrode feeder rod, I i represents the feed rod current of the i-th ground electrode feed rod, M represents the molar mass of the ground electrode feed rod, n represents the metal valence of the ground electrode feed rod, and S represents the surface area of ​​the ground electrode feed rod; The annual corrosion depth is predicted based on the corrosion rate.

4. A coastal ground electrode anti-corrosion method according to claim 3, characterized in that: The expression for predicting the annual corrosion depth based on the corrosion rate is as follows: Among them, d i represents the annual corrosion depth of the i-th ground electrode feeder rod, v represents the corrosion rate, ρ represents the density of the ground electrode feeder rod, I i represents the feed rod current of the i-th ground electrode feed rod, M represents the molar mass of the ground electrode feed rod, n represents the metal valence of the ground electrode feed rod, and S represents the surface area of ​​the ground electrode feed rod.

5. A coastal grounding electrode anti-corrosion system, characterized in that: It includes a main control module, a DC current generator, a current distribution monitor, a current measurement box and several feed rod modules, each of which is provided with a ground electrode feed rod and a sliding rheostat; wherein: The DC current generator is used to transmit the current of the external high-voltage DC transmission network to the plurality of feed rod modules; Several of the feed rod modules are connected in parallel with each other; in any of the feed rod modules, the ground electrode feed rod is used to disperse the current input by the DC current generator to the ground through the sliding rheostat; The current distribution monitor is used to obtain the current density distribution uniformity of all the ground electrode feeder rods; The main control module is used to execute the following anti-corrosion strategy for any of the ground electrode feed rods so that the current density distribution uniformity meets a preset current uniformity threshold: Obtaining the feeder rod current of the ground electrode feeder rod through the current measurement box, and then predicting the annual corrosion depth of the ground electrode feeder rod based on the feeder rod current; If the annual corrosion depth exceeds a preset depth threshold, the current of the feeding rod is controlled to decrease by adjusting the resistance of the sliding rheostat until the annual corrosion depth meets the depth threshold.

6. The coastal ground electrode anti-corrosion system according to claim 5, characterized in that: Any of the feeder rod modules includes a drainage cable, a grounding electrode well wall, a cable support and protection pipe, backfill sand and coke; wherein: The bottom end of the grounding electrode well protective wall is filled with the coke; The ground electrode feed rod is wrapped around the center of the coke; the ground electrode feed rod is electrically connected to the DC current generator through the drainage cable and the sliding rheostat; the ground electrode feed rod is used to disperse the current input by the DC current generator to the ground through the sliding rheostat; The cable support and protection tube is provided inside the grounding electrode well protective wall, and is used to support and protect the drainage cable; The drainage cable is laid along the cable support protection tube from the DC current generator to the ground electrode feed rod; The inner side of the grounding electrode well protective wall is filled with the backfill sand and gravel, and the backfill sand and gravel wrap the drainage cable and the cable support protection tube.

7. The coastal ground electrode anti-corrosion system according to claim 6, characterized in that: Any of the feed rod modules includes a temperature sensor and a temperature measuring optical cable; the temperature sensor is provided on the surface of the ground electrode feed rod; the temperature measuring optical cable is laid along the cable support protection tube from the current distribution monitor to the temperature sensor; the temperature sensor is electrically connected to the current distribution monitor through the temperature measuring optical cable; wherein: The current distribution monitor is used to obtain the temperature of the corresponding ground electrode feed rod through the temperature sensor, thereby obtaining the temperature mean square deviation of all the ground electrode feed rods based on the temperature of each ground electrode feed rod, and then analyzing the current density distribution uniformity based on the temperature mean square deviation.

8. The coastal ground electrode anti-corrosion system according to claim 6, characterized in that: Any of the feeder rod modules comprises a current measuring terminal, the current measuring terminal being used to obtain the feeder rod current of the ground electrode feeder rod through the drainage cable and to feed the feeder rod current back to the current measuring box; For the main control module, obtaining the feeder rod current of the ground electrode feeder rod through the current measurement box, and then predicting the annual corrosion depth of the ground electrode feeder rod based on the feeder rod current, includes: The corrosion rate of the ground electrode feeder rod is obtained based on the feeder rod current, and its expression is as follows: Wherein, vi represents the corrosion rate of the i-th ground electrode feed rod, Ii represents the feed rod current of the i-th ground electrode feed rod, M represents the molar mass of the ground electrode feed rod, n represents the metal valence of the ground electrode feed rod, and S represents the surface area of ​​the ground electrode feed rod; The annual corrosion depth is predicted based on the corrosion rate.

9. The coastal ground electrode anti-corrosion system according to claim 8, characterized in that: The expression for predicting the annual corrosion depth based on the corrosion rate is as follows: Wherein, di represents the annual corrosion depth of the i-th ground electrode feeder rod, v represents the corrosion rate, ρ represents the density of the ground electrode feeder rod, Ii represents the feeder rod current of the i-th ground electrode feeder rod, M represents the molar mass of the ground electrode feeder rod, n represents the metal valence of the ground electrode feeder rod, and S represents the surface area of ​​the ground electrode feeder rod.

10. A terminal device, characterized in that: comprising a processor and a memory, wherein: The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the coastal ground electrode anti-corrosion method according to any one of claims 1 to 4 according to the instructions in the program code.

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