Method and system for predicting service life of power transmission tower

Abstract

The invention provides a power transmission tower service life prediction method and system. The method comprises the following steps: establishing a macroscale power transmission tower finite element model; based on the established finite element model of the power transmission tower, carrying out loaded simulation analysis on the service performance of the uncorroded power transmission tower under an extreme condition, and obtaining a stressed weak component of the power transmission tower; establishing an electrochemical corrosion simulation model of a micro-scale weak component material; based on the established electrochemical corrosion simulation model, obtaining a quantitative analysis result of corrosion thickness loss of the weak component; and obtaining a service life prediction conclusion of the power transmission tower according to the obtained quantitative analysis result of corrosion thickness loss of the weak component in combination with the established macro-scale finite element model of the power transmission tower. According to the method, the service performance change and service life of the power transmission tower under the atmospheric corrosion condition are predicted, a scientific basis is provided for formulating a differentiated anti-corrosion strategy of a power system, and the method has important theoretical value and practical significance for guaranteeing safe, stable and efficient operation of the power system.

Description

Technical Field

[0001] The present application relates to the technical field of transmission tower corrosion resistance research, and specifically to a transmission tower service life prediction method and system. Background Art

[0002] Transmission towers are key supporting structures for transmission lines and are essential for the normal operation of power systems. However, during service, transmission towers are often damaged by corrosion, resulting in tower collapse and line disconnection, which can lead to power safety accidents. The safe and reliable operation of the power system cannot be ignored in terms of social economy and living order. With the rapid expansion of the scale of the power grid, the working environment of transmission towers has become increasingly severe, which makes them more susceptible to corrosion in complex environments and increases the risk of damage to weak parts. Transmission towers are exposed to the natural atmosphere and have been affected by atmospheric corrosion for a long time, causing gradual corrosion on their surfaces. A variety of corrosive media will be deposited on the surface of transmission tower components to form electrolyte solutions, thereby inducing electrochemical corrosion. Humidity, temperature and pollutant concentration in the atmospheric environment will jointly affect the corrosion of transmission towers. High temperature and high humidity will also accelerate the reaction rate of metals with oxygen and pollutants, exacerbating the occurrence of corrosion. When the component materials of the transmission tower are weakened to a certain extent by corrosion, or when encountering extremely harsh environments such as ice, snow, and typhoons, sudden failures of the transmission tower may occur, seriously affecting the safe operation of the transmission line.

[0003] The direct cost of State Grid Corporation for atmospheric corrosion protection is about 6 to 8 billion yuan each year, and 20% to 30% is used for anti-corrosion maintenance, repair and reinforcement during the operation phase to prevent equipment from being damaged by corrosion. However, in recent years, the number of accidents caused by material failure due to environmental corrosion has gradually increased, which shows that the current anti-corrosion effect is not ideal. The accumulated damage of these corrosions can easily lead to safety hazards in power grid equipment. Atmospheric corrosion of transmission towers is one of the main reasons for the failure of key component materials under long-term normal operating conditions, and it also causes the actual anti-corrosion life of transmission towers to be lower than the design life.

[0004] Since the influence of environmental factors in different regions on the degree of corrosion of transmission towers varies significantly, the implementation of anti-corrosion measures should take full account of regional characteristics and implement precise policies. Therefore, accurately selecting protective materials based on environmental corrosive characteristics and service conditions, quickly evaluating the corrosion resistance and life of equipment materials, discovering corrosion sites as early as possible to predict their development trends and timely technical treatment, and proposing clear corrosion resistance requirements for the service environment in selection and technical specifications can improve the current anti-corrosion status and provide technical support for differentiated anti-corrosion work. Summary of the invention

[0005] The present application provides a transmission tower service life prediction method and system, which can solve the technical problem in the prior art of lacking research on the environmental corrosion characteristics of transmission towers and predicting the service life based on the research.

[0006] In a first aspect, the present application provides a method for predicting the service life of a transmission tower, comprising the following steps: Establish a macro-scale finite element model of the transmission tower; Based on the established finite element model of the transmission tower, the load simulation analysis of the service performance of the non-corroded transmission tower under extreme conditions was carried out to obtain the weak components of the transmission tower; Establish a simulation model of electrochemical corrosion of weak component materials at the microscopic scale; Based on the established electrochemical corrosion simulation model, the quantitative analysis results of corrosion thickness loss of weak components are obtained; Based on the quantitative analysis results of corrosion loss of weak components and the established macro-scale transmission tower finite element model, the service life prediction conclusion of the transmission tower is obtained. In combination with the first aspect, in one implementation, establishing a macro-scale transmission tower finite element model specifically includes the following steps: According to the single-line diagram and engineering drawings of the transmission tower, the indirect modeling method is used to establish a geometric model of the structure in the form of points, lines, surfaces and bodies, and a macro-scale finite element model of the transmission tower is obtained.

[0007] In combination with the first aspect, in one implementation, based on the established finite element model of the transmission tower, a load simulation analysis is performed on the service performance of the non-corroded transmission tower under extreme conditions, and the extreme conditions in the step of obtaining the weak components of the transmission tower include strong wind conditions, one-phase ground wire fracture conditions, and one-phase conductor fracture conditions.

[0008] In combination with the first aspect, in one implementation, the load simulation analysis of the service performance of the non-corroded transmission tower under extreme conditions is performed based on the established transmission tower finite element model, and after obtaining the weak components of the transmission tower under stress, the following steps are also included: According to the stress conditions of the transmission tower finite element model under extreme conditions and the collapse of the transmission tower on site, the validity of the established transmission tower finite element model is verified.

[0009] In combination with the first aspect, in one embodiment, the establishment of an electrochemical corrosion simulation model of a microscopically weak component material specifically comprises the following steps: Based on the corrosion mechanism and electrochemical principles, the corrosion development model of weak component materials in the atmospheric environment is modeled with electrochemical kinetic parameters and environmental parameters as boundary conditions, and the electrochemical corrosion simulation model in the atmospheric environment is obtained.

[0010] In combination with the first aspect, in one embodiment, based on the corrosion mechanism and electrochemical principle, the corrosion development modeling of weak component materials under the atmospheric environment is performed with electrochemical kinetic parameters and environmental parameters as boundary conditions, and after obtaining the carbon steel corrosion development model under the atmospheric environment, the following steps are also included: The test parameters of the neutral salt spray test were substituted into the electrochemical corrosion simulation model under atmospheric environment to verify the effectiveness of the model.

[0011] In combination with the first aspect, in one embodiment, the step of substituting the test parameters of the neutral salt spray test into the carbon steel corrosion development model in the atmospheric environment and verifying the effectiveness of the model further includes the following steps: Based on the electrochemical corrosion simulation model with verified effectiveness, the corrosion thickness loss simulation value of the weak component is obtained; Obtain the true value of corrosion thickness loss of carbon steel atmospheric exposure test of weak components; The simulated corrosion thickness loss value of the weak component is compared with the actual corrosion thickness loss value, and the electrochemical corrosion simulation model after validity verification is corrected according to the comparison results.

[0012] In combination with the first aspect, in one embodiment, obtaining the quantitative analysis result of the corrosion thickness loss of the weak component based on the established electrochemical corrosion simulation model specifically includes the following steps: Input the environmental parameters of the carbon steel atmospheric exposure test into the electrochemical corrosion simulation model to solve for the current density of the electrolyte on the electrode surface of the weak component; Convert current density to corrosion rate; The corrosion rate is integrated and the simulated value of corrosion thickness loss of the weak component is obtained.

[0013] In a second aspect, the present application provides a transmission tower service life prediction system, comprising: Finite element model building module, used to build macro-scale transmission tower finite element model; A weak component acquisition module is connected to the finite element model establishment module for performing load simulation analysis on the service performance of the non-corroded transmission tower under extreme conditions based on the established transmission tower finite element model, and obtaining the weak components of the transmission tower; A corrosion model establishment module, which is in communication connection with the weak component acquisition module and is used to establish an electrochemical corrosion simulation model of weak component materials at a microscopic scale; A corrosion thickness loss simulation module is connected in communication with the weak component acquisition module and the corrosion model establishment module, and is used to obtain a quantitative analysis result of the corrosion thickness loss of the weak component based on the established electrochemical corrosion simulation model; The transmission tower life prediction module is in communication with the corrosion loss simulation module and is used to obtain a transmission tower service life prediction conclusion based on the obtained quantitative analysis results of the corrosion loss of weak components combined with the established macro-scale transmission tower finite element model. In conjunction with the second aspect, in one implementation, the corrosion thickness loss simulation module includes: A current density acquisition unit is connected to the weak component acquisition module and the corrosion model establishment module for inputting environmental parameters of the carbon steel atmospheric exposure test into the electrochemical corrosion simulation model to solve and obtain the current density of the electrolyte on the electrode surface of the weak component; A corrosion rate acquisition unit, which is in communication with the current density acquisition unit and is used to convert the current density into a corrosion rate; The corrosion thickness loss simulation unit is connected to the corrosion rate acquisition unit for performing integral calculation on the corrosion rate to obtain the corrosion thickness loss simulation value of the weak component.

[0014] The beneficial effects brought by the technical solution provided by the embodiment of the present application include at least: By establishing a macroscopic transmission tower model and a microscopic electrochemical corrosion simulation model, combined with the degradation law of mechanical properties of weak component materials of transmission towers in corrosive environments, the influence of the remaining thickness of weak components of transmission towers on the ultimate stress of the structure under extreme conditions was explored. Finally, the electrochemical corrosion simulation model was used to predict the corrosion development of weak component materials over time in atmospheric environments and to evaluate the life of the galvanized layer. The service performance changes and service life of the transmission tower under atmospheric corrosion conditions were predicted, which provided a scientific basis for the formulation of differentiated anti-corrosion strategies for power systems. It has important theoretical value and practical significance for ensuring the safe, stable and efficient operation of power systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A method flow chart of a transmission tower service life prediction method provided in an embodiment of the present application; Figure 2 (a) is an equivalent stress cloud diagram of the entire non-corroded transmission tower under high wind conditions provided by an embodiment of the present application; Figure 2 (b) is an equivalent stress cloud diagram of the non-corroded transmission tower leg under high wind conditions provided by an embodiment of the present application; Figure 3 A 24-fold magnified deformation cloud map of a non-corroded transmission tower under high wind conditions provided in an embodiment of the present application; Figure 4 (a) is a stress cloud diagram of the main beams of the four tower legs of the non-corroded transmission tower provided in the embodiment of the present application under high wind conditions; Figure 4 (b) is a scatter plot and a straight line fitting diagram of stress changes on the main beams of the four tower legs of the non-corroded transmission tower provided in an embodiment of the present application under high wind conditions; Figure 5 (a) is one of the equivalent stress cloud diagrams of the non-corroded transmission tower in the working condition of one phase conductor being broken provided in the embodiment of the present application; Figure 5 (b) is the second equivalent stress cloud diagram of the non-corroded transmission tower under the condition of one-phase conductor disconnection provided in the embodiment of the present application; Figure 5 (c) is the third equivalent stress cloud diagram of the non-corroded transmission tower under the condition of one-phase conductor being broken provided in the embodiment of the present application; Figure 6 (a) is one of the equivalent stress cloud diagrams of the non-corroded transmission tower in the working condition of one phase ground wire being broken provided in the embodiment of the present application; Figure 6 (b) is the second equivalent stress cloud diagram of the non-corroded transmission tower in the condition of one phase ground wire being broken provided in the embodiment of the present application; Figure 7 (a) is one of the case diagrams of the collapse of transmission towers in multiple locations provided in the embodiment of the present application; Figure 7 (b) is the second example of the collapse of transmission towers in multiple locations provided in the embodiment of the present application; Figure 7 (c) is the third example of the collapse of transmission towers in multiple locations provided in the embodiment of the present application; Figure 8 (a) is a two-dimensional cross-sectional geometric model diagram provided in an embodiment of the present application; Figure 8 (b) is a schematic diagram of mesh division of a two-dimensional cross-sectional geometric model provided in an embodiment of the present application; Fig. 9 (a) is the electrolyte potential diagram of simulated carbon steel in a neutral salt spray environment at 0 h provided in an embodiment of the present application; Fig. 9 (b) is the electrolyte potential diagram of the simulated carbon steel in the neutral salt spray environment at 1800 h provided in the embodiment of the present application; Fig. 9 (c) is a current density diagram of simulated carbon steel in a neutral salt spray environment at 0 h provided in an embodiment of the present application; Fig. 9 (d) is a current density diagram of the simulated carbon steel in a neutral salt spray environment at 1800 h provided in an embodiment of the present application; Fig.10 (a) is a graph of the corrosion rate of carbon steel in a neutral salt spray environment test and simulation provided by an embodiment of the present application; Fig.10 (b) Carbon steel corrosion thickness loss diagram in neutral salt spray environment test and simulation; Fig.11 (a) is a comparison chart of the actual corrosion thickness loss value and the simulated corrosion thickness loss value of carbon steel at the Beijing Atmospheric Exposure Test Station provided in the embodiment of the present application; Fig.11 (b) is a comparison chart of the actual corrosion thickness loss value and the simulated corrosion thickness loss value of carbon steel at Qingdao atmospheric exposure test station provided in the embodiment of the present application; Fig.11(c) is a comparison chart of the actual corrosion thickness loss value and the simulated corrosion thickness loss value of Wuhan carbon steel at the atmospheric exposure test station provided in the embodiment of the present application; Fig.11 (d) is a comparison chart of the actual corrosion thickness loss value and the simulated corrosion thickness loss value of carbon steel at the Jiangjin atmospheric exposure test station provided in the embodiment of the present application; Fig.11 (e) is a comparison chart of the actual corrosion thickness loss value and the simulated corrosion thickness loss value of carbon steel at the Guangzhou atmospheric exposure test station provided in the embodiment of the present application; Fig.11 (f) is a comparison chart of the actual corrosion thickness loss value and the simulated corrosion thickness loss value of carbon steel at the Qionghai atmospheric exposure test station provided in the embodiment of the present application; Fig.12 A comparison chart of the errors between the actual corrosion thickness loss value and the simulated corrosion thickness loss value of carbon steel at atmospheric exposure test stations in various regions provided in the embodiments of the present application; Fig.13 The annual corrosion rate diagram of carbon steel in the atmospheric exposure test station provided in the embodiment of the present application; Fig.14 (a) is a comparison chart of the actual corrosion thickness loss value and the corrected corrosion thickness loss simulation value of carbon steel at the Beijing Atmospheric Exposure Test Station provided in the embodiment of the present application; Fig.14 (b) is a comparison chart of the actual corrosion thickness loss value and the corrected corrosion thickness loss simulation value of carbon steel at Qingdao atmospheric exposure test station provided in the embodiment of the present application; Fig.14 (c) is a comparison chart of the actual corrosion thickness loss value and the corrected corrosion thickness loss simulation value of carbon steel at Wuhan atmospheric exposure test station provided in the embodiment of the present application; Fig.14 (d) is a comparison chart of the actual corrosion thickness loss value and the corrected corrosion thickness loss simulation value of carbon steel exposed to the atmosphere at Jiangjin Test Station provided in the embodiment of the present application; Fig.14 (e) is a comparison chart of the actual corrosion thickness loss value and the corrected corrosion thickness loss simulation value of carbon steel at the Guangzhou atmospheric exposure test station provided in the embodiment of the present application; Fig.14 (f) is a comparison chart of the actual corrosion thickness loss value and the corrected corrosion thickness loss simulation value of carbon steel at the Qionghai atmospheric exposure test station provided in the embodiment of the present application; Fig.15 This is a comparison chart of the actual corrosion thickness loss value and the simulated corrosion thickness loss value of carbon steel in atmospheric exposure test stations in various regions after error correction provided in the embodiments of the present application. DETAILED DESCRIPTION

[0016] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0017] First, please refer to Figure 1 The present application provides a method for predicting the service life of a transmission tower, comprising the following steps: Step S1: Establishing a macro-scale transmission tower finite element model; Step S3: Based on the established finite element model of the transmission tower, a load simulation analysis is performed on the service performance of the non-corroded transmission tower under extreme conditions to obtain the weak components of the transmission tower; Step S5: establishing an electrochemical corrosion simulation model of micro-scale weak component materials; Step S8: obtaining quantitative analysis results of corrosion thickness loss of weak components based on the established electrochemical corrosion simulation model; Step S9: Based on the obtained quantitative analysis results of the corrosion thickness loss of the weak components and the established macro-scale transmission tower finite element model, a prediction conclusion of the service life of the transmission tower is obtained. This application establishes a macro transmission tower model and a micro electrochemical corrosion simulation model, combines the degradation law of mechanical properties of weak component materials of transmission towers in a corrosive environment, and explores the influence of the remaining thickness of weak components of transmission towers on the ultimate stress of the structure under extreme conditions. Finally, the electrochemical corrosion simulation model is used to predict the corrosion development of weak component materials over time in an atmospheric environment and to evaluate the life of the galvanized layer. The service performance changes and service life of the transmission tower under atmospheric corrosion conditions are predicted, which provides a scientific basis for the formulation of differentiated anti-corrosion strategies for power systems. It has important theoretical value and practical significance for ensuring the safe, stable and efficient operation of power systems.

[0018] In one embodiment, the step S1: establishing a macro-scale transmission tower finite element model specifically includes the following steps: According to the single-line diagram and engineering drawings of the transmission tower, the indirect modeling method is used to establish a geometric model of the structure in the form of points, lines, surfaces and bodies, and a macro-scale finite element model of the transmission tower is obtained.

[0019] In a more specific embodiment, among the transmission towers of power transmission lines, the proportion of straight transmission towers is larger. Therefore, this application selects the cathead straight transmission tower 1A3-ZM1 as the research object of mechanical finite element simulation. The height of the tower is 20.5m and the nominal height is 15m. At present, the mainstream material of the transmission tower is Q355 steel. Table 1 lists its main material parameters. Due to the complex structure of the cathead type transmission tower, involving a large number of points, lines, surfaces and body elements, the direct modeling method for solving general material mechanics and structural mechanics problems is not applicable when modeling the transmission tower. The step S1: Establishing a macro-scale finite element model of the transmission tower is specifically implemented as follows: Adopting the indirect modeling method, the geometric model of the transmission tower structure is established in the form of points, lines, surfaces and volumes. According to the segment numbers on the transmission tower single-line diagram or engineering drawings, the transmission tower is decomposed into tower head module, tower body module and tower leg module, and modeled block by block. This segmented modeling method can better handle complex structures and make the modeling process more controllable and accurate. Considering the cross-sectional stress of the tower material and the division of the unit grid, the transmission tower is simplified into a beam structure and modeled using the BEAM188 solid beam element. According to the structural characteristics of the transmission tower, different specifications of load-bearing components are selected in its design. Specifically, the angle steels used in the 1A3-ZM1 transmission tower include 12 different specifications of equal-sided and equal-thickness angle steels (L40×3, L50×4, L63×5, etc.); Considering that the orientation of the angle steel will affect the mechanical analysis structure of the finite element model of the transmission tower, the orientation of the angle steel is determined by the direction of the line between I and J and the orientation of the Z control key point when modeling the angle steel. When modeling the transmission tower finite element, the orientation of each angle steel is determined strictly according to the design drawings.

[0020] Table 1 Main material parameters of finite element model

[0021] In a specific embodiment, step S1: establishing a macro-scale transmission tower finite element model is specifically implemented as follows: According to the engineering drawings, the overall dimensions are unified while simplifying the common nodes of the angle steel of the transmission tower; Establish a wireframe model in 3D CAD software to obtain key point coordinates, then input the point coordinates into finite element software to form a transmission tower lattice model, and connect the points to form a transmission tower line model; According to the cross-sectional stress of the tower material and the division of the unit grid, the transmission tower is simplified into a beam structure; Strictly follow the design drawings, assign the model the corresponding size of the angle steel section and adjust the angle steel direction; The finite element modeling of the entire transmission tower is completed, and a macro-scale finite element model of the transmission tower is obtained.

[0022] In one embodiment, in the established finite element model of the transmission tower, only the modeling of the angle steel is considered, and the non-angle steel components such as the connecting steel plates and bolts in the transmission tower structure are ignored. After the step S1: establishing the macro-scale finite element model of the transmission tower, the following steps are also included: Step S2: Perform quality correction on the established macro-scale transmission tower finite element model.

[0023] In one embodiment, the step S2: performing quality correction on the established macro-scale transmission tower finite element model specifically includes the following steps: Step S21: according to the actual drawing of the transmission tower, obtaining the mass proportion of the structural connectors of the transmission tower, where the mass proportion is the ratio of the weight of the connectors to the actual weight M of the transmission tower; Step S22: According to the mass proportion of the structural connecting parts of the transmission tower, the mass magnification factor is calculated by calculating the tower foot support reaction force F and the actual mass M of the transmission tower according to formula (1): : Formula (1) Step S23: According to the calculated mass magnification factor, in subsequent simulations, the material density is increased by k times to match the actual deadweight of the transmission tower, and the mass of the established macro-scale transmission tower finite element model is corrected to reduce the error.

[0024] In one embodiment, during the simulation of the transmission tower, the internal and external loads borne by the transmission tower need to be considered: the internal load refers to the weight of the transmission tower itself, while the external load covers a variety of dynamic and static forces that affect the tower structure. The external loads mainly include: the force of the conductor and ground wire acting on the hanging point of the transmission tower, the force generated by the deadweight of the insulator, the wind load, the ice load, and the asymmetric load when the conductor and ground wire are broken, etc. The step S3: based on the established finite element model of the transmission tower, the service performance of the uncorroded transmission tower under extreme conditions is simulated and analyzed, and the extreme conditions in the step of obtaining the weak components of the transmission tower include strong wind conditions, one-phase ground wire broken conditions, and one-phase conductor broken conditions; the specific implementation is: (a) High wind conditions: It is crucial to consider the load combination under extreme conditions - high wind conditions (basic wind speed) for transmission tower design. The standard stipulates that the basic wind speed is based on the annual maximum wind speed averaged over a 10-minute interval at the local meteorological station as a sample (using the extreme value type I distribution as a probability model). The height of the general transmission line for statistical wind speed should be 10 m above the ground. The design maximum wind speed of a 110 kV line is converted into a wind speed of about 28 m / s at a height of 10 m above the ground, which is equivalent to a force 10 gale. When the wind direction is perpendicular to the line (i.e., a 90° wind direction angle), and there is no ice accumulation and the conductor and ground wire are intact, the maximum load combination under this condition needs to be evaluated. The basic wind speed is the benchmark for the wind-resistant design of the structure and is a key load factor that must be considered when evaluating the stability and safety of the transmission tower. The permanent loads under this condition include the gravity loads of the conductor and ground wire, insulators and their accessories, and the transmission tower structure. The variable loads include the wind loads of the conductor and ground wire perpendicular to the line direction and the wind loads of the transmission tower. This should be fully considered in the design and stability analysis of transmission towers; In the design of transmission towers, their ability to resist longitudinal loads must also be fully considered. For linear transmission towers, it is also very important to consider the unbalanced tension when one phase ground wire or one phase conductor is disconnected. Since the transmission tower is equipped with 3-phase conductors and 2-phase ground wires, there are 5 potential disconnection scenarios, each of which corresponds to a load model. The load conditions of the transmission tower are analyzed under the following two conditions: (b) Extreme conditions: When the temperature is -5°C and there is ice cover, assuming there is no wind action, if a phase conductor breaks and the ground wire is intact, the permanent load is the gravity load of the conductor and ground wire, insulators and their accessories, transmission tower structure, etc., and the variable load is the tension difference on both sides of the conductor; (c) Extreme conditions: Also under the condition of -5℃ and ice cover, assuming no wind action, if one-phase ground wire breaks and the conductor remains intact, the permanent load is the gravity load of the conductor and ground wire, insulator and its accessories, transmission tower structure, etc., and the variable load is the tension difference on both sides of the ground wire.

[0025] In a specific embodiment, the load parameters of the transmission tower under three extreme conditions of strong wind condition, one-phase ground wire break condition and one-phase conductor break condition are shown in Table 2: Table 2 Load parameters of transmission towers under three extreme conditions (N)

[0026] The simulation results of the service performance of transmission towers under three extreme conditions are analyzed as follows: (1) Under strong wind conditions: The equivalent stress distribution cloud diagram of the transmission tower under strong wind conditions is as follows Figure 2 (a) and Figure 2 As shown in (b), the four main beams are subjected to greater equivalent stress. The maximum equivalent stress of the uncorroded transmission tower is 194.69 MPa (the numerical result is consistent with the internal data of the power grid), which does not exceed the yield limit of the material, and this stress value appears at the tower foot.

[0027] Under high wind conditions, the maximum total displacement of the transmission tower is calculated to be 90.002 mm. Figure 3 This is a deformation cloud map magnified 24 times. The deformation starts from the top of the tower and gradually decreases along the tower body, showing a linear decreasing trend, and the entire tower body is deflected in the windward direction (tension side).

[0028] Then solve the stress cloud diagrams on the main beams of the four tower legs separately as follows Figure 4 As shown in (a), the maximum value of the equivalent stress is also located at the tower foot. Then the specific stress conditions on each tower leg main beam are detected and the change trend of the equivalent stress is plotted as follows: Figure 4As shown in (b). The horizontal axis in the figure is the value of the coordinate point of the finite element model in the vertical Z-axis direction of the model, and the vertical axis represents the equivalent stress value of the corresponding coordinate point. Its change trend is linearly decreasing from the tower leg upward and presents a symmetrical distribution on the tower body. Among them, axis 1 and axis 3 are located on the side close to the tilt direction of the transmission tower, generating greater stress; while axis 2 and axis 4 are located on the side away from the tilt direction, generating smaller stress.

[0029] (2) When one phase conductor is disconnected: Next, the structural response of the transmission tower in the case of a three-phase conductor break (one of the three phases is broken) is analyzed. Through finite element simulation, different conductor breakage scenarios were simulated, and the equivalent stress distribution of the transmission tower under three different conditions was obtained. The analysis shows that in all conductor breakage scenarios, the four main beams of the transmission tower are subjected to higher equivalent stresses than the auxiliary beams. Despite this, the equivalent stress values ​​do not exceed the yield limit of the material, indicating that the structure has sufficient safety margin in design. Further observations show that the position of the conductor breakage has a significant effect on the stress distribution. When a single-phase conductor on the left or right side breaks, a greater equivalent stress is generated on the tension side and near the hanging point of the conductor on that side (such as Figure 5 (a) and Figure 5 When the conductor at the middle position breaks, a greater equivalent stress is generated on the tension side near the middle hanging point (as shown in (c)). Figure 5 (b)). However, due to the symmetry of the force on the transmission tower after the fracture, the overall structural stability of the transmission tower is slightly better in this case. Therefore, the transmission tower still has a certain structural integrity and stability when one phase of the conductor is broken; in operation and maintenance, the influence of the conductor fracture position on the stress distribution can be considered.

[0030] (3) Condition of one-phase ground wire disconnection: Finally, the structural response of the transmission tower under the condition of two-phase ground wire break (one of the two phases is broken) is analyzed. Through finite element simulation, different ground wire break scenarios are simulated, and the equivalent stress distribution of the transmission tower under two different conditions is obtained. The results show that when one-phase ground wire is broken, the four main beams of the transmission tower produce greater equivalent stress than the auxiliary beams, and the stress in all areas does not exceed the yield limit of the material, which shows that the safety of the design is guaranteed. Further observations show that the upper part of the transmission tower is the key area that bears large equivalent stress, especially on the side where the ground wire is disconnected (such as Figure 6). In addition, the different locations of ground wire breakage also lead to differences in equivalent stress distribution. Since the cross-sectional area of ​​the ground wire is generally larger than that of the conductor, its breakage will cause a large weight imbalance, which will have a significant impact on the unbalanced tension of the transmission tower. This unbalanced tension may have a more important impact on the overall stability of the transmission tower. When the ground wire breaks, the unbalanced tension on the transmission tower is greater, and the impact on the stability of the transmission tower is also greater. Therefore, during the operation and maintenance of the transmission tower, attention can be paid to the impact of ground wire breakage on structural stability, and effective measures can be taken to improve the transmission tower's ability to resist unbalanced tension when the ground wire breaks, so as to ensure the safe and stable operation of the power grid.

[0031] The simulation results of the service performance of transmission towers under three extreme conditions are analyzed and the following results are obtained: The weakest components of the transmission tower under strong wind conditions are located at the tower legs, especially the tower feet; The weak component of the transmission tower under the condition that one phase of the three-phase conductor is broken is that the transmission tower still has a certain structural integrity and stability when one phase of the three-phase conductor is broken; the influence of the conductor break position on the stress distribution can be considered in operation and maintenance; When one of the two-phase ground wires breaks, the transmission tower will be subjected to greater unbalanced tension, which will have a greater impact on the stability of the transmission tower. Therefore, during the operation and maintenance of the transmission tower, attention should be paid to the impact of the ground wire breakage on the structural stability.

[0032] In summary, by constructing a macro-scale finite element model of the transmission tower and setting the loading conditions of the overhead transmission line under extreme conditions according to the current industry standards, the finite element simulation of the transmission tower was carried out. It was found that the weak stress areas of the transmission tower are located in the tower legs, especially the tower feet. The components of the tower legs and tower feet are all made of carbon steel.

[0033] In one embodiment, the load simulation analysis of the service performance of the non-corroded transmission tower under three extreme conditions is performed. The three transmission tower finite element models all obtain reasonable and expected results and verify each other, but the effectiveness of the model still needs to be further verified in combination with the on-site tower collapse situation. Step S3: Based on the established transmission tower finite element model, the load simulation analysis of the service performance of the non-corroded transmission tower under extreme conditions is performed. After obtaining the weak components of the transmission tower, the following steps are also included: Step S4: According to the stress conditions of the transmission tower finite element model under extreme conditions and the collapse of the transmission tower on site, the validity of the established transmission tower finite element model is verified.

[0034] In one embodiment, the step S4: verifying the validity of the established finite element model of the transmission tower according to the stress conditions of the finite element model of the transmission tower under extreme conditions and the collapse of the transmission tower on site is specifically implemented as follows: Under strong wind conditions, the weak stress areas of the transmission tower are mainly concentrated near the tower legs, and the equivalent stress generated after the main beam bears the load is relatively large. Therefore, under strong convective weather conditions that often last from a few minutes to several hours, the ambient wind speed is generally greater than the design wind speed, and the transmission tower is more likely to bend and topple at the tower legs. In addition, through the investigation results of accident sites in many places, it was verified that transmission towers often collapse from the tower legs. Photos of the case site are shown in the figure below. Figure 7 As shown in the figure, the validity of the above finite element model can be verified. In subsequent research, the corrosion behavior of the weak components of the transmission tower legs will be further simulated to explore the impact of corrosion loss on its service life.

[0035] By comparing the simulation results with the on-site tower collapse case, the effectiveness of the finite element model of the transmission tower was verified; at the same time, the weak stress areas of the transmission tower also coincided with the common corrosion sites in the transmission tower corrosion survey, all located in the tower leg part.

[0036] In one embodiment, the step S5: establishing an electrochemical corrosion simulation model of a microscopically weak component material specifically comprises the following steps: Based on the corrosion mechanism and electrochemical principles, the corrosion development of weak component materials in the atmospheric environment was modeled with electrochemical kinetic parameters and environmental parameters as boundary conditions, and the electrochemical corrosion simulation model in the atmospheric environment was obtained; among which, the electrochemical kinetic parameters included the anodic exchange current density, the cathodic exchange current density, the anodic equilibrium potential, the cathodic equilibrium potential, the anodic Tafel slope and the cathodic Tafel slope; the environmental parameters included the annual average temperature (T), the annual average humidity (RH), the sulfate deposition rate (Pd) and the chloride ion deposition rate (Sd).

[0037] Since the tower legs and tower feet of the transmission tower are both made of carbon steel, the electrochemical corrosion simulation model of microscopically weak component materials established in this application is a carbon steel electrochemical corrosion simulation model.

[0038] Since the corrosion of weak component materials in the atmospheric environment is a complex system affected by the combined effects of many climate variables, the formation and transformation of corrosion products during liquid film evaporation and condensation are particularly complex. In order to build a more reasonable electrochemical corrosion simulation model, this application proposes the following assumptions: (1) Ignoring the evaporation and condensation of the liquid film: In the electrochemical corrosion simulation model, it is assumed that the thickness of the liquid film on the carbon steel surface remains stable, and the evaporation and condensation processes are not involved. Therefore, the salt concentration in the liquid film is also considered to be a constant value; (2) Simplified corrosion product transformation: Considering the complex transformation process of corrosion products of carbon steel under dry-wet alternating conditions and the lack of kinetic data on related intermediate reactions, this process was simplified in the electrochemical corrosion simulation model, focusing only on the generation of the primary reaction Fe(OH)2. (3) Ignoring electrochemical activity: It is assumed that the corrosion products have no electrochemical activity in the electrochemical corrosion simulation model, and their influence on the subsequent corrosion process of the substrate is not considered.

[0039] In one embodiment, step S5: based on the corrosion mechanism and electrochemical principle, with electrochemical kinetic parameters and environmental parameters as boundary conditions, the corrosion development model of the weak component material in the atmospheric environment is modeled to obtain the electrochemical corrosion simulation model in the atmospheric environment, which is specifically implemented as follows: Based on the corrosion mechanism and electrochemical principles, the "Corrosion, Secondary Current" physical field interface of COMSOL software is used to input electrochemical kinetic parameters and environmental parameters as boundary conditions to model the corrosion development of carbon steel under atmospheric environment; in some cases, the two-dimensional model of COMSOL Multiphysics is an effective simplification of three-dimensional problems. Especially in the following two cases: when the three-dimensional model has infinite width and the result change in the width direction is almost negligible; or when the three-dimensional model is relatively wide, but the results in the middle area along the width direction remain unchanged, and the results near the edge are not the focus of the study. In this application, the main focus is on the corrosion development and evolution of carbon steel at the microscopic scale, and the results near the edge are not the focus of the study. Therefore, considering saving computing resources and time, the research of this application is carried out by establishing a two-dimensional profile model, thereby taking into account both simulation accuracy and computing cost, and realizing simplified modeling of complex problems.

[0040] This application uses COMSOL software to establish a micro-scale carbon steel electrochemical corrosion simulation model for weak components. By inputting electrochemical kinetic parameters and environmental parameters, the electrolyte current density on the surface of carbon steel electrodes under various atmospheric conditions is calculated. The current density obtained is then converted into corrosion rate and corrosion thickness loss, realizing the prediction of the corrosion development of carbon steel over time under different atmospheric environments.

[0041] In this application, the "Corrosion, Secondary Current" interface provided by the electrochemical module in COMSOL Multiphysics is selected to define the physical field. This interface can describe the current distribution and potential distribution in the corrosion cell. A key assumption in the model is the stability of the electrolyte composition, that is, it is assumed that the effect of its changes on the current and potential distribution can be ignored. In order to study the trend of corrosion behavior over time, the model adopts a transient analysis method based on initial conditions. The input of the model includes the environmental parameters of the atmospheric exposure test station (including temperature, humidity, pollutant concentration, etc.) and the electrochemical kinetic parameters of carbon steel, all of which are derived from actual measurements.

[0042] The electrochemical corrosion simulation model can be used to preliminarily solve the electrolyte current density on the electrode surface. The current density obtained can be converted into the corrosion rate through formula (2), and then the corrosion loss can be obtained by integrating the corrosion rate. This conversion process is based on the quantitative relationship between the corrosion rate and the current density. The area in the corrosion rate-time image also reflects the change in the amount of corrosion in the corresponding time, and the corrosion loss simulation value is obtained; when the carbon steel electrode contacts the electrolyte film covering its surface, a potential difference is formed between the two.

[0043] Formula (2) Where A is ampere, a is year, and mm / a represents the annual corrosion amount.

[0044] Under atmospheric conditions, chloride ions (Cl - ) and sulfate ions (SO4 2- ) will promote the formation of low-potential anode areas on the surface of carbon steel, thereby accelerating the corrosion process. Based on the above corrosion mechanism, this application establishes an electrochemical corrosion simulation model of carbon steel. The thin electrolyte liquid film above the carbon steel surface serves as the calculation domain, and the liquid film layer is immediately below the carbon steel substrate. The middle boundary of the calculation domain, that is, the electrode surface of oxygen and iron, is the key area where local electrochemical reactions occur. Here, the dissolution reaction of carbon steel at the anode and the reduction reaction of oxygen at the cathode are considered. In order to quantitatively analyze these processes, a two-dimensional cross-section geometric model is constructed as shown in Figure 8 As shown, fine mesh division is performed on it, and the corrosion loss simulation value of carbon steel is calculated for each mesh separately to ensure the accuracy and reliability of the simulation results.

[0045] In one embodiment, considering that the environmental parameters in the atmosphere are actually in constant change, the application uses the annual average environmental parameters as input parameters to simulate the corrosion behavior. The various parameters of the standard neutral salt spray test are constant, and the simulation results correspond to the effects of the real environmental parameters; therefore, the environmental parameters of the neutral salt spray conditions are input into the carbon steel electrochemical corrosion simulation model to preliminarily verify the effectiveness of the established model. The step S5: based on the corrosion mechanism and electrochemical principle, with the electrochemical kinetic parameters and environmental parameters as boundary conditions, the corrosion development model of the weak component material under the atmospheric environment is modeled. After obtaining the carbon steel corrosion development model under the atmospheric environment, the following steps are also included: Step S6: Substitute the test parameters of the neutral salt spray test into the electrochemical corrosion simulation model under the atmospheric environment to verify the effectiveness of the model.

[0046] In a specific embodiment, the carbon steel is Q355 steel.

[0047] In one embodiment, the step S6: substituting the test parameters of the neutral salt spray test into the electrochemical corrosion simulation model under the atmospheric environment to verify the effectiveness of the model specifically includes the following steps: According to the standard of "Artificial Atmosphere Corrosion Test Salt Spray Test" (GB / T 10125-2012), a series of indoor accelerated corrosion tests were conducted on Q355 steel in a neutral salt spray environment. Q355 steel plate coupons with a size of 100 mm×50 mm×5 mm were made. The test included 10 corrosion cycles, specifically 5, 10, 15, 20, 25, 35, 45, 55, 65, and 75 days. The test equipment used was CASSER-TTR-TS0-2F from SUGA, Japan. The test used a 5 wt% (pH 7.0) NaCl solution, and the temperature of the test environment was controlled within the range of 35℃±1℃. Before the test, all samples were carefully processed, including punching and numbering, deburring, cleaning oil stains, and weighing and measuring dimensions, so as to accurately analyze the test results. After the test, the samples were derusted, dried, and cooled; and weighed to calculate the average weight loss of the material after corrosion.

[0048] The corrosion rate and corrosion loss data of the electrochemical corrosion simulation model of carbon steel verified by the salt spray test are based on the calculated average values ​​of three carbon steel specimens within a 1800 h period. The environmental parameters of the neutral salt spray test are substituted into the electrochemical corrosion simulation model of carbon steel as boundary conditions, and a solution step of 1 h is set to simulate the corrosion behavior of carbon steel specimens in 1800 h. The electrolyte potential and electrolyte current density of carbon steel at 0 h and 1800 h in the neutral salt spray environment are shown in Figure 2. Fig. 9 As shown in the figure, it shows a trend of continuous dynamic change. Comparing the corrosion rate and the corresponding corrosion loss data of the neutral salt spray test and simulation, Fig.10 As shown in the figure, both show an upward trend. The corrosion loss continues to increase approximately linearly with time. Although there are differences in the growth trend of the corrosion rate and corrosion loss results between the simulation and the test, the overall values ​​are not much different, and the corrosion loss results at the final 1800 h are also relatively similar, which can preliminarily verify the effectiveness of the carbon steel electrochemical corrosion simulation model.

[0049] This application preliminarily verifies the validity of the model by substituting the relevant parameters of the neutral salt spray test into the model. Then the environmental parameters of the carbon steel atmospheric exposure test are input into the model, and the model is corrected by adjusting the limiting current density parameter in sections according to the error between the simulated value of carbon steel corrosion thickness loss and the true value of corrosion thickness loss. After correction, the error between the simulated value of carbon steel corrosion thickness loss and the true value is reduced from 29.3% to 14.7%, thereby constructing the final carbon steel electrochemical corrosion simulation model.

[0050] In one embodiment, the step S6: substituting the test parameters of the neutral salt spray test into the carbon steel corrosion development model under the atmospheric environment, and after verifying the effectiveness of the model, further comprises the following steps: Step S7: Correct the electrochemical corrosion simulation model after validity verification.

[0051] In one embodiment, the step S7: performing model correction on the electrochemical corrosion simulation model after validity verification specifically includes the following steps: Based on the electrochemical corrosion simulation model with verified effectiveness, the corrosion thickness loss simulation value of the weak component is obtained; Obtain the true value of corrosion thickness loss of carbon steel atmospheric exposure test of weak components; The simulated corrosion thickness loss value of the weak component is compared with the actual corrosion thickness loss value, and the electrochemical corrosion simulation model after validity verification is corrected according to the comparison results.

[0052] In a specific embodiment, the step S7: performing model correction on the electrochemical corrosion simulation model after validity verification is specifically implemented as follows: Step S71: converting the electrolyte current density on the electrode surface into a corrosion rate by using formula (2), and then integrating the current density to obtain the growth trend of corrosion thickness loss; Step S72: Compare the simulated corrosion thickness loss value of carbon steel at the atmospheric exposure test station with the actual corrosion thickness loss value. Fig.11 As shown; The results show that although the model can simulate the corrosion development trend of carbon steel, the accuracy of the model still needs to be improved: in the early stage of corrosion, the simulated value is lower than the true value; in the later stage of corrosion, the simulated value is higher than or close to the true value. From the slope of the carbon steel corrosion thickness loss curve, the electrochemical corrosion simulation model before correction failed to effectively simulate the inhibitory effect of corrosion products on the corrosion process, and the growth of corrosion thickness loss did not see an inflection point; the error between the simulated value and the true value of carbon steel corrosion thickness loss at each test station was calculated and statistically analyzed. Fig.12 As shown, the average error is 29.3%. In subsequent work, step S73: the carbon steel electrochemical corrosion simulation model is corrected to reduce the error and improve the model accuracy.

[0053] In one embodiment, the corrosion loss of carbon steel is derived to obtain the annual corrosion rate of carbon steel, and its variation trend over time is as follows: Fig.13As shown. In the six test stations, the annual corrosion rate of carbon steel showed a downward trend. In the first two years, the corrosion rate dropped sharply; during the period of 2 to 8 years, the downward trend gradually slowed down until it reached a relatively small corrosion rate; during the period of 8 to 16 years, carbon steel continued to corrode at this smaller corrosion rate. This change in corrosion rate is mainly due to the accumulation of corrosion products that affects the corrosion process. Corrosion products gradually accumulate on the surface of carbon steel to form a protective layer, thereby slowing down the further progress of corrosion. Therefore, in order to more accurately simulate the real atmospheric corrosion behavior of carbon steel, step S73 is specifically implemented as follows: According to the actual corrosion situation, the limiting current density of the carbon steel electrochemical corrosion simulation model is adjusted in sections to simulate the corrosion behavior of carbon steel in sections; the sectioning is based on the size of the corrosion rate; specifically, when the actual corrosion rate of carbon steel is greater than the preset rate, more specifically, the first limiting current density is used for simulation; when the actual corrosion rate of carbon steel is less than the preset rate, the second limiting current density is used for simulation, and the first limiting current density is greater than the second limiting current density; for example: during the period from 0 to 8 years, due to the high corrosion rate, a higher limiting current density is used for simulation; and during the period from 8 to 16 years, due to the low and stable corrosion rate, a lower limiting current density is used for simulation. The segmented simulation method can better simulate the corrosion behavior of carbon steel at different stages, thereby improving the accuracy and reliability of the model.

[0054] After simulating the corrosion behavior of carbon steel in sections and smoothing the simulated corrosion loss value, a comparison with the actual corrosion loss value was obtained. Fig.14 As shown, the corrected corrosion loss simulation value is obtained based on the corrected electrochemical corrosion simulation model. In the early stage of corrosion, most of the simulated values ​​are still smaller than the true values. This may be because in the early stage of corrosion, the corrosion rate is fast and there are many influencing factors, which leads to a certain deviation in the simulation model; however, in the late stage of corrosion, the curves of the simulated value and the true value gradually approach each other, indicating that the segmented simulation method can better reflect the corrosion behavior of carbon steel in the late stage of corrosion. The change in the slope of the image reflects that the corrected model can indeed reflect the inhibitory effect of corrosion products on the corrosion process. With the accumulation of corrosion products, the corrosion rate gradually decreases, and the increase in corrosion loss gradually slows down. The error between the simulated value and the true value of the corrosion loss of carbon steel at each test station is calculated and statistically shown in the figure below. Fig.15 As shown in the figure, the error of each test station is within 20%. After correction, the average error of the carbon steel electrochemical corrosion simulation model is reduced from 29.3% to 14.7%. The corrected electrochemical corrosion simulation model can better simulate the corrosion behavior of carbon steel at different stages.

[0055] In one embodiment, the step S8: obtaining the quantitative analysis result of the corrosion thickness loss of the weak component based on the established electrochemical corrosion simulation model, specifically includes the following steps: Input the environmental parameters of the carbon steel atmospheric exposure test into the electrochemical corrosion simulation model to solve for the current density of the electrolyte on the electrode surface of the weak component; Convert current density to corrosion rate; The corrosion rate is integrated and the simulated value of corrosion thickness loss of the weak component is obtained.

[0056] In one embodiment, the service life prediction of transmission towers in different regions is realized by combining the macroscopic transmission tower mechanical model and the microscopic carbon steel electrochemical corrosion simulation model of this chapter. The step S9: according to the obtained quantitative analysis results of corrosion loss of weak components combined with the established macroscopic transmission tower finite element model, the service life prediction conclusion of the transmission tower is obtained, which specifically includes the following steps: Through tensile tests, the accelerated corrosion tests of Q355 steel in neutral salt spray, SO2, and hot and humid environments were studied to obtain the effects of different types of corrosion defects on its mechanical properties. Then, the mechanical properties of corrosion pit defects were simulated and simulation studies on tensile tests of Q355 steel in different corrosion cycles were conducted to obtain simulation results of tensile tests of Q355 steel in different corrosion cycles. Based on the finite element model of the transmission tower, the authors explored the extent to which the remaining thickness of the transmission tower legs would exceed the yield limit of Q355 steel under extreme conditions, and obtained the thickness yield limit of the transmission tower legs. Based on the corrosion simulation model, the corrosion development of carbon steel in atmospheric corrosion environment is predicted over time and the life of the galvanized layer is evaluated to obtain the corrosion life of carbon steel and galvanized layer; Based on the simulation research results of Q355 steel tensile tests in different corrosion cycles, the thickness yield limit of transmission tower legs, and the corrosion life of carbon steel and galvanized layers, the service life of transmission towers in different regions is predicted.

[0057] In a second aspect, the present application provides a transmission tower service life prediction system, comprising: Finite element model building module, used to build macro-scale transmission tower finite element model; A weak component acquisition module is connected to the finite element model establishment module for performing load simulation analysis on the service performance of the non-corroded transmission tower under extreme conditions based on the established transmission tower finite element model, and obtaining the weak components of the transmission tower; A corrosion model establishment module, which is in communication connection with the weak component acquisition module and is used to establish an electrochemical corrosion simulation model of weak component materials at a microscopic scale; A corrosion thickness loss simulation module is connected in communication with the weak component acquisition module and the corrosion model establishment module, and is used to obtain a quantitative analysis result of the corrosion thickness loss of the weak component based on the established electrochemical corrosion simulation model; The transmission tower life prediction module is in communication with the corrosion loss simulation module and is used to obtain a transmission tower service life prediction conclusion based on the obtained quantitative analysis results of the corrosion loss of weak components combined with the established macro-scale transmission tower finite element model. In one embodiment, the corrosion thickness loss simulation module includes: A current density acquisition unit is connected to the weak component acquisition module and the corrosion model establishment module for inputting environmental parameters of the carbon steel atmospheric exposure test into the electrochemical corrosion simulation model to solve and obtain the current density of the electrolyte on the electrode surface of the weak component; A corrosion rate acquisition unit, which is in communication with the current density acquisition unit and is used to convert the current density into a corrosion rate; The corrosion thickness loss simulation unit is connected to the corrosion rate acquisition unit for performing integral calculation on the corrosion rate to obtain the corrosion thickness loss simulation value of the weak component.

[0058] In a third aspect, an embodiment of the present application also provides a readable storage medium.

[0059] The readable storage medium of the present application stores a transmission tower service life prediction program, wherein when the transmission tower service life prediction program is executed by a processor, the steps of the transmission tower service life prediction method as described above are implemented.

[0060] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for predicting the service life of a transmission tower, characterized in that: The following steps are involved: Establish a macro-scale finite element model of the transmission tower; Based on the established finite element model of the transmission tower, the load simulation analysis of the service performance of the non-corroded transmission tower under extreme conditions was carried out to obtain the weak components of the transmission tower; Establish a simulation model of electrochemical corrosion of weak component materials at the microscopic scale; Based on the established electrochemical corrosion simulation model, the quantitative analysis results of corrosion thickness loss of weak components are obtained; Based on the quantitative analysis results of corrosion loss of weak components and the established macro-scale transmission tower finite element model, the service life prediction conclusion of the transmission tower is obtained.

2. The transmission tower service life prediction method according to claim 1, characterized in that: The establishment of a macro-scale transmission tower finite element model specifically includes the following steps: According to the single-line diagram and engineering drawings of the transmission tower, the indirect modeling method is used to establish a geometric model of the structure in the form of points, lines, surfaces and bodies, and a macro-scale finite element model of the transmission tower is obtained.

3. The transmission tower service life prediction method according to claim 1, characterized in that: Based on the established finite element model of the transmission tower, a load simulation analysis is performed on the service performance of the non-corroded transmission tower under extreme conditions, and the extreme conditions in the step of obtaining the weak components of the transmission tower include strong wind conditions, one-phase ground wire fracture conditions and one-phase conductor fracture conditions.

4. The transmission tower service life prediction method according to claim 1, characterized in that: The method further includes the following steps after performing load simulation analysis on the service performance of the non-corroded transmission tower under extreme conditions based on the established transmission tower finite element model and obtaining the weak components of the transmission tower under stress: According to the stress conditions of the transmission tower finite element model under extreme conditions and the collapse of the transmission tower on site, the validity of the established transmission tower finite element model is verified.

5. The transmission tower service life prediction method according to claim 1, characterized in that: The establishment of the electrochemical corrosion simulation model of microscopic weak component materials specifically includes the following steps: Based on the corrosion mechanism and electrochemical principles, the corrosion development model of weak component materials in the atmospheric environment is modeled with electrochemical kinetic parameters and environmental parameters as boundary conditions, and the electrochemical corrosion simulation model in the atmospheric environment is obtained.

6. The transmission tower service life prediction method according to claim 1, characterized in that: Based on the corrosion mechanism and electrochemical principle, the corrosion development model of weak component materials in the atmospheric environment is modeled with electrochemical kinetic parameters and environmental parameters as boundary conditions. After obtaining the carbon steel corrosion development model in the atmospheric environment, the following steps are also included: The test parameters of the neutral salt spray test were substituted into the electrochemical corrosion simulation model under atmospheric environment to verify the effectiveness of the model.

7. The transmission tower service life prediction method according to claim 6, characterized in that: Substituting the test parameters of the neutral salt spray test into the carbon steel corrosion development model in the atmospheric environment and verifying the effectiveness of the model further includes the following steps: Based on the electrochemical corrosion simulation model after effectiveness verification, the corrosion thickness loss simulation value of the weak component is obtained; Obtain the true value of corrosion thickness loss of carbon steel atmospheric exposure test of weak components; The simulated corrosion thickness loss value of the weak component is compared with the actual corrosion thickness loss value, and the electrochemical corrosion simulation model after validity verification is corrected according to the comparison results.

8. The method for predicting the service life of a transmission tower according to claim 1, characterized in that: The method of obtaining the quantitative analysis results of the corrosion thickness loss of the weak component based on the established electrochemical corrosion simulation model specifically includes the following steps: Input the environmental parameters of the carbon steel atmospheric exposure test into the electrochemical corrosion simulation model to solve for the current density of the electrolyte on the electrode surface of the weak component; Convert current density to corrosion rate; The corrosion rate is integrated and the simulated value of corrosion thickness loss of the weak component is obtained.

9. A transmission tower service life prediction system, characterized in that: include: Finite element model building module, used to build macro-scale transmission tower finite element model; A weak component acquisition module is connected to the finite element model establishment module for performing load simulation analysis on the service performance of the non-corroded transmission tower under extreme conditions based on the established transmission tower finite element model, and obtaining the weak components of the transmission tower; A corrosion model establishment module, which is in communication connection with the weak component acquisition module and is used to establish an electrochemical corrosion simulation model of weak component materials at a microscopic scale; A corrosion thickness loss simulation module is connected to the weak component acquisition module and the corrosion model establishment module for obtaining quantitative analysis results of the corrosion thickness loss of the weak component based on the established electrochemical corrosion simulation model; The transmission tower life prediction module is in communication with the corrosion loss simulation module and is used to obtain a transmission tower service life prediction conclusion based on the obtained quantitative analysis results of the corrosion loss of weak components combined with the established macro-scale transmission tower finite element model.

10. The transmission tower service life prediction system according to claim 9, characterized in that: The corrosion thickness loss simulation module includes: A current density acquisition unit is connected to the weak component acquisition module and the corrosion model establishment module for inputting environmental parameters of the carbon steel atmospheric exposure test into the electrochemical corrosion simulation model to solve and obtain the current density of the electrolyte on the electrode surface of the weak component; A corrosion rate acquisition unit, which is in communication with the current density acquisition unit and is used to convert the current density into a corrosion rate; The corrosion thickness loss simulation unit is connected to the corrosion rate acquisition unit for performing integral calculation on the corrosion rate to obtain the corrosion thickness loss simulation value of the weak component.

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