A method for evaluating the icing deterioration state of catenary wrist insulator based on electric field distortion factor

Abstract

The present invention provides a method for evaluating the icing deterioration state of catenary wrist-arm insulators based on the electric field distortion factor, which is characterized in that a test platform for evaluating the icing deterioration state of catenary wrist-arm insulators based on the electric field distortion factor is built to simulate the actual icing environment conditions. First, the conditions in the environmental simulation test chamber are adjusted by intelligent environmental control equipment. Then, a test voltage is applied to the catenary wrist-arm insulator, the test current under different icing conditions is measured by a current test coil, and the theoretical calculation formula of the current is optimized by an optimization algorithm. Finally, the icing deterioration state of the catenary wrist-arm insulator is evaluated. The beneficial effect of the present invention is that it provides a method for evaluating the icing deterioration state of catenary wrist-arm insulators based on the electric field distortion factor, builds a test platform, realizes the accurate evaluation of the deterioration state of catenary wrist-arm insulators under icing conditions, and provides an important guarantee for the safe and reliable operation of the rail transit system.

Description

Technical Field

[0001] The invention belongs to the field of evaluation of the deterioration state of catenary mast insulators, and particularly relates to a method for evaluating the icing deterioration state of catenary mast insulators based on an electric field distortion factor. Background Art

[0002] In the rail transit system, the catenary mast insulator, as an important part of the high-speed railway power transmission system, undertakes the dual functions of electrical insulation and mechanical support. The reliability of the performance of the catenary mast insulator directly affects the safe and stable operation of the rail transit. With the rapid development of high-speed railways, the catenary system operates under various climatic conditions, including complex environments such as alpine cold, humidity, icing, etc., which puts higher requirements on the performance of insulators. Especially in the cold winter environment, ice layers are likely to form on the surface of the catenary mast insulator, resulting in a decline in the performance of the catenary mast insulator, affecting the normal operation of the rail transit system, and even triggering safety accidents. Therefore, the deterioration problem of the catenary mast insulator under icing conditions must be given sufficient attention, and it is necessary to timely evaluate and detect the deterioration state of the catenary mast insulator and take corresponding protective measures.

[0003] The icing phenomenon will cause changes in the surface electric field distribution of the catenary mast insulator, resulting in electric field distortion, thereby accelerating the deterioration process of the insulator. Icing not only increases the leakage current on the surface of the insulator, but may also trigger partial discharge, further damaging the insulation performance of the catenary mast insulator.

[0004] Currently, the evaluation methods for the icing deterioration state of catenary mast insulators mainly rely on empirical judgment and simple physical detection, and most of them do not consider the electric field distortion under icing conditions, resulting in limitations in the evaluation of the deterioration state of catenary mast insulators under severe cold climate conditions, and it is difficult to provide accurate and timely early warnings and maintenance suggestions. Therefore, the invention constructs a platform for evaluating the icing deterioration state of catenary mast insulators based on an electric field distortion factor, and proposes a method for evaluating the icing deterioration state of catenary mast insulators based on an electric field distortion factor based on this platform, accurately evaluates the deterioration state of the catenary mast insulator, and puts forward maintenance opinions to improve the safety and reliability of the operation of the rail transit system. Summary of the Invention

[0005] In order to accurately evaluate the deterioration state of the catenary mast insulator under icing conditions, the invention provides a method for evaluating the icing deterioration state of the catenary mast insulator based on an electric field distortion factor. The technical solution for achieving the purpose of the invention is as follows:

[0006] Step 1: A catenary mast insulator icing deterioration state evaluation platform based on the electric field distortion factor is built. The platform includes: a host computer (1), a power frequency voltage controller (2), a power frequency voltage generator (3), a power frequency generator grounding electrode (31), a high-voltage coaxial cable (4), a high-voltage switch (51), a grounding switch (52), a high-precision voltage divider (6), an environmental simulation test chamber (7), a high-voltage test electrode one (81), a high-voltage test electrode two (82), a catenary mast insulator test sample (9), a mast insulator angle regulator (10), an intelligent angle adjustment control device (11), a current test coil (12), a grounding cable (13), a grounding grid (14), an experimental data acquisition unit (15), a wireless data transmission module one (161), a wireless data transmission module two (162), a wireless data transmission module (163), an ice layer thickness measuring instrument (17), an ice prism length measuring instrument (18), an intelligent ice quantity regulator (19), a blower (20), an adjustable wind direction filter screen (21), a wind speed comprehensive control device (22), and an ice maker (23);

[0007] The input end of the power frequency voltage controller (2) is connected to the host computer (1), the output end of the power frequency voltage controller (2) is connected to the input end of the power frequency voltage generator (3), the output end of the power frequency voltage generator (3) is connected to the left end of the high-voltage switch (51) via the high-voltage coaxial cable (4), the right end of the high-voltage switch (51) is connected to the input end of the high-precision voltage divider (6), the output end of the high-precision voltage divider (6) is connected to the high-voltage test electrode one (81), the high-voltage test electrode one (81) is connected to the upper end of the catenary mast insulator test sample (9), the lower end of the catenary mast insulator test sample (9) is connected to the high-voltage test electrode two (82), the high-voltage test electrode two (82) is fixed on the mast insulator angle regulator (10), the upper and lower ends of the grounding switch (52) are respectively connected to the high-voltage test electrode two (82) and the grounding cable (13), and the output end of the grounding cable (13) is connected to the grounding grid (14);

[0008] The grounding end of the power frequency voltage generator (3) is connected to the power frequency generator grounding electrode (31);

[0009] The current test coil (12) is sleeved on the grounding cable (13), and the output end of the current test coil (12) is connected to the input end of the experimental data acquisition unit (15);

[0010] The output end of the experimental data acquisition unit (15) is connected to the input end of the wireless data transmission module one (161), and the wireless data transmission module one (161) is wirelessly connected to the host computer (1);

[0011] The input end of the intelligent angle adjustment control device (11) is connected to the host computer (1), and the output end of the intelligent angle adjustment control device (11) is connected to the pantograph insulator angle adjuster (10); the output ends of the ice layer thickness measuring instrument (17) and the ice prism length measuring instrument (18) are connected to the wireless data transmission module II (162); the wireless data transmission module II (162) is wirelessly connected to the host computer (1);

[0012] The input end of the intelligent ice quantity adjuster (19) is connected to the host computer (1), and the output end of the intelligent ice quantity adjuster (19) is connected to the ice maker (23); the wind speed comprehensive control device (22) is respectively connected to the fan (20) and the wireless data transmission module III (163); the wireless data transmission module III (163) is wirelessly connected to the host computer (1);

[0013] The high-voltage test electrode I (81), the pantograph insulator test sample (9), the high-voltage test electrode II (82), the pantograph insulator angle adjuster (10), the ice layer thickness measuring instrument (17), the ice prism length measuring instrument (18), the fan (20), the adjustable wind direction filter screen (21), and the ice maker (23) are fixed inside the environmental simulation test chamber (7);

[0014] Step 2: Based on the established evaluation platform for the icing deterioration state of pantograph insulators based on the electric field distortion factor, an evaluation method for the icing deterioration state of pantograph insulators based on the electric field distortion factor is proposed, including the following steps:

[0015] S1: Set the installation angle of the pantograph insulator test sample (9) in the host computer (1) as θ a , and the host computer (1) controls the pantograph insulator angle adjuster (10) to start working by controlling the intelligent angle adjustment control device (11), so that the included angle between the pantograph insulator test sample (9) and the horizontal plane is θ a ;

[0016] S2: Set the ice quantity in the environmental simulation test chamber (7) in the host computer (1) as H a , and the host computer (1) controls the ice making quantity of the ice maker (23) as H by controlling the intelligent ice quantity adjuster (19) a ;

[0017] S3: Set the wind speed V in the host computer (1) a, the host computer (1) transmits the wind speed setting signal to the wind speed comprehensive control device (22) through the wireless data transmission module three (163), and controls the rotation speed n of the fan (20) to increase uniformly from 0 through the wind speed comprehensive control device (22); at the same time, the wind speed comprehensive control device (22) measures the wind speed v in the environmental simulation test chamber (7) in real time, and the wireless data transmission module three (163) wirelessly transmits the measurement result of the wind speed comprehensive control device (22) to the host computer (1), and the host computer (1) judges the wind speed v. If |V a - v| < E, the rotation speed n of the fan (20) remains unchanged;

[0018] S4: Keep the environmental conditions in the environmental simulation test chamber (7) unchanged. After waiting for a time ΔT, measure the maximum ice layer thickness d max and the minimum ice layer thickness d min of the catenary mast insulator test sample (9) at this time with the ice layer thickness measuring instrument (17) and the ice prism length measuring instrument (18), max and the maximum ice prism length l min and the minimum ice prism length l

[0019] ; the wireless data transmission module two (162) wirelessly transmits the measurement results of the ice layer thickness measuring instrument (17) and the ice prism length measuring instrument (18) to the host computer (1); r S5: The host computer (1) issues a control signal to the power frequency voltage controller (2), so that the power frequency voltage generator (3) performs a constant voltage boost process on the catenary mast insulator test sample (9), boosts by ΔU every Δt time, and performs a total of N voltage boosts. After each voltage boost, record the time t at this time and the voltage U1 of the power frequency voltage generator (3), and then measure the voltage U2 and current I of the catenary mast insulator test sample (9) at this time by the high-precision voltage divider (6) and the current test coil (12)

[0020] and return them to the host computer (1) through the experimental data acquisition unit (15), and disconnect the high-voltage switch (51) and the grounding switch (52); i S6: Obtain the calculated value I of the power frequency test current of the catenary mast insulator test sample (9) through the following formula

[0021]

[0022] In formula (1), t is the duration of the simulated environment, k is the weight coefficient, y is the linear error factor, x is the integration variable, and U2 is the voltage measured across the catenary mast insulator test sample (9);

[0023] S7: Use an optimization algorithm to optimize the modeling of formula (1) to obtain the value y0 that minimizes the error. The specific steps are as follows:

[0024] 1) Randomly generate the initial solution δ, and calculate the objective function:

[0025]

[0026] In formula (2), represents the objective function, I im is the calculated value of the m-th power frequency current, I rm is the measured value of the m-th power frequency current, and N is the number of tests;

[0027] 2) Generate a perturbed new solution δ', and calculate the objective function Δf = f(δ) - f(δ'); if Δf ≥ 0, accept the new solution, otherwise, obtain the new solution according to the probability acceptance criterion;

[0028] 3) Judge whether the iteration number is reached. If it is reached, go to step 4); otherwise, go to step 2);

[0029] 4) Judge whether the termination condition is satisfied. If it is satisfied, the operation ends and the optimal solution is output; otherwise, reset the iteration number and go to step 2);

[0030] S8: Substitute y0 obtained in S7 into formula (1) to obtain the power frequency test current I i ' calculation formula of the optimized catenary mast insulator sample (9):

[0031]

[0032] S9: Calculate the electric field distortion factor σ of the catenary mast insulator based on the optimized power frequency test current I i ':

[0033]

[0034] In formula (3), I i ' is the optimized power frequency test current, θ a is the angle between the catenary mast insulator sample (9) and the horizontal plane, d max is the maximum ice layer thickness, d min is the minimum ice layer thickness, l max is the maximum ice prism length, l min is the minimum ice prism length, and N is the number of tests;

[0035] S10: Calculate the icing deterioration state evaluation factor η of the catenary mast insulator:

[0036]

[0037] In formula (5), I i ' is the optimized power frequency test current, σ is the electric field distortion factor, and N is the number of tests;

[0038] S11: Evaluate based on the icing deterioration state evaluation factor η of the catenary mast insulator obtained from the above steps. When η ∈ (0, 7.49], it indicates that the catenary mast insulator has no deterioration; when η ∈ (7.49, 67.94], it indicates that the catenary mast insulator has slight deterioration; when η ∈ (67.94, +∞), it indicates that the catenary mast insulator has serious deterioration, and it is recommended to replace the catenary mast insulator.

[0039] The beneficial effects of the present invention are as follows:

[0040] 1) A catenary mast insulator icing deterioration state evaluation platform based on the electric field distortion factor is built, which can effectively simulate the icing condition of the catenary mast insulator under actual environmental conditions;

[0041] 2) The upper computer intelligent control system is adopted to simplify the operation process and improve the work efficiency and the convenience of data management;

[0042] 3) The intelligent environmental control equipment can achieve precise control of the test conditions, ensure the stability and repeatability of the test environment, and greatly improve the accuracy of the evaluation of the icing deterioration state of the catenary mast insulator;

[0043] 4) The integrated wireless data transmission module realizes the real-time remote transmission and monitoring of test data, enhances the accessibility and immediacy of the data, and improves the flexibility and efficiency of the overall operation. Description of the Drawings

[0044] Figure 1 It is a schematic diagram of a catenary mast insulator icing deterioration evaluation platform based on the electric field distortion factor of the present invention. Specific Embodiments

[0045] The following further describes the specific embodiments of the present invention in conjunction with the drawings. A method for evaluating the icing deterioration state of a catenary mast insulator based on the electric field distortion factor, the specific embodiments include the following steps:

[0046] Step 1: A catenary mast insulator icing deterioration state evaluation platform based on the electric field distortion factor is built. The platform includes: a host computer (1), a power frequency voltage controller (2), a power frequency voltage generator (3), a power frequency generator grounding electrode (31), a high-voltage coaxial cable (4), a high-voltage switch (51), a grounding switch (52), a high-precision voltage divider (6), an environmental simulation test chamber (7), a high-voltage test electrode I (81), a high-voltage test electrode II (82), a catenary mast insulator test sample (9), a mast insulator angle adjuster (10), an intelligent angle adjustment control device (11), a current test coil (12), a grounding cable (13), a grounding grid (14), an experimental data acquisition unit (15), a wireless data transmission module I (161), a wireless data transmission module II (162), a wireless data transmission module (163), an ice layer thickness measuring instrument (17), an ice ridge length measuring instrument (18), an intelligent ice quantity adjuster (19), a fan (20), an adjustable wind direction filter screen (21), a wind speed comprehensive control device (22), and an ice maker (23);

[0047] The input end of the power frequency voltage controller (2) is connected to the host computer (1), the output end of the power frequency voltage controller (2) is connected to the input end of the power frequency voltage generator (3), the output end of the power frequency voltage generator (3) is connected to the left end of the high-voltage switch (51) via the high-voltage coaxial cable (4), the right end of the high-voltage switch (51) is connected to the input end of the high-precision voltage divider (6), the output end of the high-precision voltage divider (6) is connected to the high-voltage test electrode I (81), the high-voltage test electrode I (81) is connected to the upper end of the catenary mast insulator test sample (9), the lower end of the catenary mast insulator test sample (9) is connected to the high-voltage test electrode II (82), the high-voltage test electrode II (82) is fixed on the mast insulator angle adjuster (10), the upper and lower ends of the grounding switch (52) are respectively connected to the high-voltage test electrode II (82) and the grounding cable (13), and the output end of the grounding cable (13) is connected to the grounding grid (14);

[0048] The grounding end of the power frequency voltage generator (3) is connected to the power frequency generator grounding electrode (31);

[0049] The current test coil (12) is sleeved on the grounding cable (13), and the output end of the current test coil (12) is connected to the input end of the experimental data acquisition unit (15);

[0050] The output end of the experimental data acquisition unit (15) is connected to the input end of the wireless data transmission module I (161), and the wireless data transmission module I (161) is wirelessly connected to the host computer (1);

[0051] The input end of the intelligent angle adjustment control device (11) is connected to the host computer (1), and the output end of the intelligent angle adjustment control device (11) is connected to the pantograph insulator angle regulator (10); the output ends of the ice layer thickness measuring instrument (17) and the ice prism length measuring instrument (18) are connected to the wireless data transmission module II (162); the wireless data transmission module II (162) is wirelessly connected to the host computer (1);

[0052] The input end of the intelligent ice quantity regulator (19) is connected to the host computer (1), and the output end of the intelligent ice quantity regulator (19) is connected to the ice maker (23); the wind speed comprehensive control device (22) is respectively connected to the fan (20) and the wireless data transmission module III (163); the wireless data transmission module III (163) is wirelessly connected to the host computer (1);

[0053] The high-voltage test electrode I (81), the pantograph insulator test sample (9), the high-voltage test electrode II (82), the pantograph insulator angle regulator (10), the ice layer thickness measuring instrument (17), the ice prism length measuring instrument (18), the fan (20), the adjustable wind direction filter screen (21), and the ice maker (23) are fixed inside the environmental simulation test chamber (7);

[0054] Step 2: Based on the established evaluation platform for the icing deterioration state of pantograph insulators based on the electric field distortion factor, an evaluation method for the icing deterioration state of pantograph insulators based on the electric field distortion factor is proposed, including the following steps:

[0055] The first step: Set the installation angle of the pantograph insulator test sample (9) in the host computer (1) as θ a , and the host computer (1) controls the pantograph insulator angle regulator (10) to start working by controlling the intelligent angle adjustment control device (11), so that the included angle between the pantograph insulator test sample (9) and the horizontal plane is θ a ;

[0056] The second step: Set the ice quantity in the environmental simulation test chamber (7) in the host computer (1) as H a , and the host computer (1) controls the ice making amount of the ice maker (23) to be H by controlling the intelligent ice quantity regulator (19) a ;

[0057] The third step: Set the wind speed V in the host computer (1) a, the host computer (1) transmits the wind speed setting signal to the wind speed comprehensive control device (22) through the wireless data transmission module three (163), and controls the rotational speed n of the fan (20) to increase uniformly from 0 through the wind speed comprehensive control device (22); meanwhile, the wind speed comprehensive control device (22) measures the wind speed v in the environmental simulation test chamber (7) in real time, and the wireless data transmission module three (163) wirelessly transmits the measurement result of the wind speed comprehensive control device (22) to the host computer (1), and the host computer (1) judges the wind speed v. If |V a - v| < E, the rotational speed n of the fan (20) is kept unchanged;

[0058] Step 4: Keep the environmental conditions in the environmental simulation test chamber (7) unchanged. After waiting for a time ΔT, measure the maximum ice layer thickness d max , the minimum ice layer thickness d min and the maximum ice prism length l max , the minimum ice prism length l min of the catenary cantilever insulator specimen (9) at this time with the ice layer thickness measuring instrument (17) and the ice prism length measuring instrument (18); the wireless data transmission module two (162) wirelessly transmits the measurement results of the ice layer thickness measuring instrument (17) and the ice prism length measuring instrument (18) to the host computer (1);

[0059] Step 5: Send a control signal to the power frequency voltage controller (2) through the host computer (1), so that the power frequency voltage generator (3) performs a constant voltage boost process on the catenary cantilever insulator specimen (9), boosting by ΔU every Δt time, for a total of N voltage boosts. After each voltage boost, record the time t and the voltage U1 of the power frequency voltage generator (3) at this time, and then measure the voltage U2 and current I r of the catenary cantilever insulator specimen (9) at this time by the high-precision voltage divider (6) and the current test coil (12), and return them to the host computer (1) through the experimental data acquisition unit (15), and disconnect the high-voltage switch (51) and the grounding switch (52);

[0060] Step 3: Obtain the calculated value I of the power frequency test current of the catenary cantilever insulator specimen (9) through the following formula i :

[0061]

[0062] In formula (1), t is the duration of the simulation environment, k is the weight coefficient, y is the linear error factor, x is the integration variable, and U2 is the voltage measured across the catenary cantilever insulator specimen (9);

[0063] Step 4: Use an optimization algorithm to optimize and model formula (1) to obtain the value y0 that minimizes the error. The specific steps are as follows:

[0064] Step 1: Randomly generate an initial solution δ and calculate the objective function:

[0065]

[0066] In formula (2), represents the objective function, I im is the calculated value of the m-th power frequency current, I rm is the measured value of the m-th power frequency current, and N is the number of tests;

[0067] Step 2: Generate a perturbed new solution δ' and calculate the objective function Δf = f(δ) - f(δ'); if Δf ≥ 0, accept the new solution, otherwise, obtain the new solution according to the probability acceptance criterion;

[0068] Step 3: Judge whether the iteration times are reached. If so, go to step 4); otherwise, go to step 2);

[0069] Step 4: Judge whether the termination condition is satisfied. If so, end the operation and output the optimal solution; otherwise, reset the iteration times and go to step 2);

[0070] Step 5: Substitute y0 obtained in S7 into formula (1) to get the power frequency test current I of the optimized catenary mast insulator sample (9) i Calculation formula:

[0071]

[0072] Step 5. Based on the optimized power frequency test current I i Calculate the electric field distortion factor σ of the catenary mast insulator:

[0073]

[0074] In formula (3), I i ' is the optimized power frequency test current, θ a is the angle between the catenary mast insulator sample (9) and the horizontal plane, d max is the maximum ice layer thickness, d min is the minimum ice layer thickness, l max is the maximum ice prism length, l min is the minimum ice prism length, and N is the number of tests;

[0075] Step 6: Calculate the icing deterioration state evaluation factor η of the catenary mast insulator:

[0076]

[0077] In formula (5), I i ' is the optimized power frequency test current, σ is the electric field distortion factor, and N is the number of tests;

[0078] Evaluate based on the catenary mast insulator icing deterioration state evaluation factor η obtained from the above steps. When η ∈ (0, 7.49], it indicates that the catenary mast insulator has no deterioration; when η ∈ (7.49, 67.94], it indicates that the catenary mast insulator has slight deterioration; when η ∈ (67.94, +∞), it indicates that the catenary mast insulator has serious deterioration, and it is recommended to replace the catenary mast insulator.

Claims

1. A method for evaluating the icing deterioration state of catenary wrist insulator based on electric field distortion factor, characterized in that The steps are as follows: Step 1: Build an evaluation platform for the icing deterioration state of catenary mast insulators based on the electric field distortion factor. The platform includes: a host computer (1), a power frequency voltage controller (2), a power frequency voltage generator (3), a power frequency generator grounding electrode (31), a high-voltage coaxial cable (4), a high-voltage switch (51), a grounding switch (52), a high-precision voltage divider (6), an environmental simulation test chamber (7), a high-voltage test electrode I (81), a high-voltage test electrode II (82), a catenary mast insulator test sample (9), a mast insulator angle regulator (10), an intelligent angle adjustment control device (11), a current test coil (12), a grounding cable (13), a grounding grid (14), an experimental data acquisition unit (15), a wireless data transmission module I (161), a wireless data transmission module II (162), a wireless data transmission module (163), an ice layer thickness measuring instrument (17), an ice ridge length measuring instrument (18), an intelligent ice quantity regulator (19), a fan (20), an adjustable wind direction filter screen (21), a wind speed comprehensive control device (22), and an ice maker (23); The input end of the power frequency voltage controller (2) is connected to the host computer (1), the output end of the power frequency voltage controller (2) is connected to the input end of the power frequency voltage generator (3), the output end of the power frequency voltage generator (3) is connected to the left end of the high-voltage switch (51) via the high-voltage coaxial cable (4), the right end of the high-voltage switch (51) is connected to the input end of the high-precision voltage divider (6), the output end of the high-precision voltage divider (6) is connected to the high-voltage test electrode I (81), the high-voltage test electrode I (81) is connected to the upper end of the catenary mast insulator test sample (9), the lower end of the catenary mast insulator test sample (9) is connected to the high-voltage test electrode II (82), the high-voltage test electrode II (82) is fixed on the mast insulator angle regulator (10), the upper and lower ends of the grounding switch (52) are respectively connected to the high-voltage test electrode II (82) and the grounding cable (13), and the output end of the grounding cable (13) is connected to the grounding grid (14); The grounding end of the power frequency voltage generator (3) is connected to the power frequency generator grounding electrode (31); The current test coil (12) is sleeved on the grounding cable (13), and the output end of the current test coil (12) is connected to the input end of the experimental data acquisition unit (15); The output end of the experimental data acquisition unit (15) is connected to the input end of the wireless data transmission module I (161), and the wireless data transmission module I (161) is wirelessly connected to the host computer (1); The input end of the intelligent angle adjustment control device (11) is connected to the host computer (1), and the output end of the intelligent angle adjustment control device (11) is connected to the mast insulator angle regulator (10); the output ends of the ice layer thickness measuring instrument (17) and the ice ridge length measuring instrument (18) are connected to the wireless data transmission module II (162); the wireless data transmission module II (162) is wirelessly connected to the host computer (1); The input end of the intelligent ice quantity regulator (19) is connected to the upper computer (1), and the output end of the intelligent ice quantity regulator (19) is connected to the ice maker (23); the wind speed comprehensive control device (22) is respectively connected to the fan (20) and the wireless data transmission module three (163); the wireless data transmission module three (163) is wirelessly connected to the upper computer (1); The high-voltage test electrode one (81), the catenary boom insulator test sample (9), the high-voltage test electrode two (82), the boom insulator angle regulator (10), the ice layer thickness measuring instrument (17), the ice prism length measuring instrument (18), the fan (20), the adjustable wind direction filter screen (21), and the ice maker (23) are fixed inside the environmental simulation test chamber (7); Step 2: Based on the established catenary boom insulator icing deterioration state evaluation platform based on the electric field distortion factor, an evaluation method for the catenary boom insulator icing deterioration state based on the electric field distortion factor is proposed, including the following steps: S1: Set the installation angle of the catenary boom insulator test sample (9) as θ in the host computer (1). a , and the host computer (1) controls the intelligent angle adjustment control device (11) to make the boom insulator angle adjuster (10) start working, so that the included angle between the catenary boom insulator test sample (9) and the horizontal plane is θ. a ; S2: Set the ice amount in the environmental simulation test chamber (7) to H in the host computer (1) a , and the host computer (1) controls the ice making amount of the ice maker (23) to be H by controlling the intelligent ice amount regulator (19) a ; S3: Set the wind speed V in the host computer (1). a , the host computer (1) transmits the wind speed setting signal to the wind speed comprehensive control device (22) through the wireless data transmission module three (163), and controls the rotation speed n of the fan (20) to increase uniformly from 0 through the wind speed comprehensive control device (22); at the same time, the wind speed comprehensive control device (22) measures the wind speed v in the environmental simulation test chamber (7) in real time, and the wireless data transmission module three (163) wirelessly transmits the measurement result of the wind speed comprehensive control device (22) to the host computer (1), and the host computer (1) judges the wind speed v. If |V a - v| < E, then keep the rotation speed n of the fan (20) unchanged; S4: Keep the environmental conditions in the environmental simulation test chamber (7) unchanged. After a waiting time ΔT, measure the maximum ice layer thickness d max , the minimum ice layer thickness d min , the maximum ice prism length l max , and the minimum ice prism length l min of the catenary cantilever insulator specimen (9) at this time using the ice layer thickness measuring instrument (17) and the ice prism length measuring instrument (18); The wireless data transmission module II (162) wirelessly transmits the measurement results of the ice layer thickness measuring instrument (17) and the ice prism length measuring instrument (18) to the host computer (1); S5: The host computer (1) sends a control signal to the power frequency voltage controller (2), so that the power frequency voltage generator (3) performs a constant voltage boost process on the catenary wrist arm insulator test sample (9), boosting the voltage by ΔU every Δt time, and performing a total of N voltage boosts. After each voltage boost, record the time t and the voltage U1 of the power frequency voltage generator (3) at this time. Then, measure the voltage U2 and current I of the catenary wrist arm insulator test sample (9) at this time by the high-precision voltage divider (6) and the current test coil (12), and return them to the host computer (1) through the experimental data acquisition unit (15). Disconnect the high-voltage switch (51) and the grounding switch (52); r , and return them to the host computer (1) through the experimental data acquisition unit (15), and disconnect the high-voltage switch (51) and the grounding switch (52); S6: Obtain the calculated value I of the power frequency test current of the catenary mast insulator specimen (9) through the following formula i : In formula (1), t is the duration of the simulated environment, k is the weight coefficient, y is the linear error factor, x is the integration variable, and U2 is the voltage measured at both ends of the catenary boom insulator test sample (9); S7: Use an optimization algorithm to optimize and model formula (1) to obtain the value y0 that minimizes the error. The specific steps are as follows: 1) Randomly generate the initial solution δ and calculate the objective function: The expression in formula (2) represents the objective function, I im is the calculated value of the m-th power frequency current, I rm is the measured value of the m-th power frequency current, and N is the number of tests; 2) Generate a perturbed new solution δ', and calculate the objective function Δf = f(δ) - f(δ'); if Δf ≥ 0, accept the new solution, otherwise, obtain the new solution according to the probability acceptance criterion; 3) Determine whether the iteration times are reached. If so, go to step 4), otherwise, go to step 2); 4) Determine whether the termination condition is satisfied. If so, the operation ends and the optimal solution is output. Otherwise, reset the iteration times and go to step 2); S8: Substitute y0 obtained in S7 into formula (1) to obtain the power frequency test current I of the optimized catenary mast insulator specimen (9). i Calculation formula: S9: Based on the optimized power frequency test current I i 'Calculate the electric field distortion factor σ of the catenary wrist insulator: In formula (3), I i ' is the optimized power frequency test current, θ a is the included angle between the catenary mast insulator specimen (9) and the horizontal plane, d max is the maximum ice layer thickness, d min is the minimum ice layer thickness, l max is the maximum ice prism length, l min is the minimum ice prism length, and N is the number of tests; S10: Calculate the catenary boom insulator icing deterioration state evaluation factor η: I in Equation (5) i ' is the optimized power frequency test current, and σ is the electric field distortion factor; S11: Evaluate based on the catenary boom insulator icing deterioration state evaluation factor η obtained in the above steps. When η ∈ (0, 7.49], it indicates that the catenary boom insulator has no deterioration; when η ∈ (7.49, 67.94], it indicates that the catenary boom insulator has slight deterioration; when η ∈ (67.94, +∞), it indicates that the catenary boom insulator has serious deterioration, and it is recommended to replace the catenary boom insulator.

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