Evaluation method for severity level of service environment of power grid equipment based on corrosion aging

Abstract

The present invention discloses a method for evaluating the severity level of the service environment of power grid equipment based on corrosion and aging, comprising the following steps: S1. Determining the materials used for each major component of the power grid equipment; S2. Obtaining parameter data on the corrosion and aging status of each material; S3. Establishing a relationship model between the corrosion and aging status of each material and its key performance, thereby obtaining functional changes of each component; S4. Based on the functional changes of each component, evaluating the performance changes of the entire power grid equipment and determining the severity level of the service environment of the power grid equipment. The present invention evaluates the severity level of the service environment based on the corrosion and aging of the materials of the power grid equipment, reflecting the impact of the long-term cumulative effects of the service environment on the power grid equipment. Moreover, using the life of the power grid equipment as a grading of environmental severity can intuitively display the degree of impact of the service environment on the performance and life of the power grid equipment.

Description

Technical Field

[0001] The present invention relates to a technology for evaluating the severity of a service environment of power grid equipment, and in particular to a method for evaluating the severity level of a service environment of power grid equipment based on corrosion and aging. Background Art

[0002] The various environmental parameters in the service environment of power grid equipment can cause varying degrees of corrosion and aging of its components and materials, impacting the functionality of the equipment. Differences in service environment characteristics across regions also lead to significant variations in the degree of impact on power grid equipment. To understand the status of power grid equipment during service, it is necessary to evaluate the severity of the service environment.

[0003] Most existing methods for evaluating the severity of service environments use materials for characterization, using factors such as the amount of corrosion or light loss to measure the severity of the service environment. However, for complete power grid equipment, existing environmental severity characterization methods cannot intuitively display the extent of the environment's impact on the function and lifespan of the equipment. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for evaluating the severity level of the service environment of power grid equipment based on corrosion and aging, which can intuitively display the impact of the service environment on the performance and life of power grid equipment.

[0005] The object of the present invention is achieved by the following technical measures: a method for evaluating the severity level of the service environment of power grid equipment based on corrosion aging, characterized by comprising the following steps:

[0006] S1. Determine the materials used for the main components of power grid equipment;

[0007] S2. Obtaining corrosion aging state parameter data of various materials;

[0008] S3. Establish a relationship model between the corrosion and aging status of various materials and their key performance, and then obtain the functional changes of each component;

[0009] S4. Evaluate the performance changes of the entire power grid equipment based on the functional changes of each component and determine the severity level of the service environment of the power grid equipment.

[0010] The present invention evaluates the severity level of the service environment based on the corrosion and aging of the materials of power grid equipment, reflecting the impact of the long-term cumulative effect of the service environment on power grid equipment. In addition, the life of the power grid equipment is used as the classification of environmental severity, which can intuitively show the degree of influence of the service environment on the performance and life of the power grid equipment.

[0011] The corrosion aging data described in the present invention include corrosion amount, porosity and compression permanent set rate, etc.

[0012] The key properties of a material are determined according to the role it plays in a component. The key properties of the material described in the present invention are electrical conductivity, mechanical properties, sealing properties or insulation properties.

[0013] In step S3 of the present invention, by measuring the key properties of materials in various corrosion and aging states and combining the impact of the corrosion and aging states on the key properties of the materials, a relationship model between the corrosion and aging states of various materials and their key properties is established.

[0014] In the step S3 of the present invention, the functional change of the component is obtained based on the impact of the change of the key performance of the material on the function of its component and in combination with the corrosion and aging state of the material.

[0015] In the step S4 of the present invention, the weight of the impact of each major component on the performance of the power grid equipment is analyzed based on the function of each major component of the power grid equipment.

[0016] In the step S4 of the present invention, the power grid equipment failure criterion is set according to the overall performance requirements of the power grid equipment.

[0017] The severity level of the service environment of the power grid equipment described in the present invention is measured by the service life of the power grid equipment. The shorter the service life, the higher the severity level. The service life of the power grid equipment 0-5 years, 5-10 years, 10-15 years, and 15-20 years correspond to the severity levels S1, S2, S3, and S4 of the service environment of the power grid equipment, respectively.

[0018] The present invention judges the corrosion and aging conditions of power grid equipment at different service times based on the corrosion and aging conditions of materials used in power grid equipment at different times, evaluates the service life of power grid equipment, and further divides the service environment severity levels of power grid equipment.

[0019] Compared with the prior art, the present invention has the following significant effects:

[0020] The present invention evaluates the severity level of the service environment based on the corrosion and aging of the materials of power grid equipment, reflecting the impact of the long-term cumulative effect of the service environment on power grid equipment. In addition, the life of the power grid equipment is used as the classification of environmental severity, which can intuitively show the degree of influence of the service environment on the performance and life of the power grid equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0023] like Figure 1As shown in the figure, a method for evaluating the severity level of the service environment of power grid equipment based on corrosion aging of the present invention comprises the following steps:

[0024] 1. Determine the materials used for the main components of power grid equipment;

[0025] This embodiment takes the power distribution automation terminal (FTU) of the power grid equipment as the object and establishes the severity level evaluation of the marine atmosphere type of the FTU in Qionghai, Hainan.

[0026] The main components of the distribution automation terminal are sealing rubber, terminal block and aviation plug. In this embodiment, only the sealing rubber, terminal block and aviation plug are selected as examples.

[0027] The materials used for these components are pure copper, nitrile rubber, nickel plating, etc. as basic materials, and the environmental severity level is determined based on the corrosion and aging status of the basic materials.

[0028] 2. Obtain data on corrosion aging parameters for various materials. This can be obtained through the National Materials Science Data Center or the National Materials Natural Environment Field Test Station. Corrosion aging parameters include corrosion volume, porosity, and compression set.

[0029] 3. Establish a relationship model between the corrosion and aging status of various materials and their key performance, and then obtain the functional changes of each component;

[0030] In steps 2 and 3, the primary contact material of the terminal block in this embodiment is copper. Copper is primarily used as a conductive material in power grid equipment, and its key performance is conductivity. Corrosion products on the surface of copper are non-conductive, resulting in a decrease in copper conductivity. Based on outdoor data from the Qionghai National Field Experiment Station in Hainan and the laws of corrosion aging, the corrosion thicknesses of the copper at 5, 10, 15, and 20 years were determined to be 3.6μm, 4.5μm, 5.2μm, and 5.8μm, respectively. The conductivity of the copper in this corrosion-aged state was measured. Combining the effect of corrosion aging on the conductivity of the copper, corresponding to the aforementioned time periods and corrosion thickness, the conductivity decreased by 20%, 30%, 55%, and 65%, respectively. This relationship model between the corrosion aging state of copper and its conductivity was established. This decrease in conductivity caused the voltage drop of the terminal block to change to 38mV, 93mV, 185mV, and 237mV, respectively, thus capturing the functional change of the terminal block component. Measurements showed that when the voltage drop reached 185mV, the electrical conductivity of the contacts at both ends of the terminal block failed.

[0031] Nickel plating is commonly used in aviation plugs and primarily serves as a conductive material in equipment, with conductivity being a key performance characteristic. The corrosion depth of the nickel plating after 5, 10, 15, and 20 years was 1.2μm, 2.7μm, 4.6μm, and 6.3μm, respectively. The conductivity of the nickel plating in its aged state was measured. The effect of corrosion aging on the conductivity of the nickel plating was investigated, and corresponding to the time and corrosion thickness, the conductivity decreased by 12%, 19%, 28%, and 35%, respectively. This relationship model was established between the corrosion aging state of the nickel plating and its conductivity. This decrease in conductivity caused the contact resistance to decrease to 3mΩ, 7mΩ, 9mΩ, and 21mΩ, respectively, capturing the functional changes of the aviation plug component. 10mΩ is the critical contact resistance for failure.

[0032] Nitrile rubber is usually used as a sealing rubber material. The compression permanent deformation rate of nitrile rubber in the 5th, 10th, 15th and 20th years is 11%, 26%, 31% and 36% respectively. The general standard stipulates that when the compression permanent deformation rate of nitrile rubber is greater than 25%, the sealing rubber is considered to have failed.

[0033] 4. Based on the functional changes of each component, evaluate the performance changes of the entire power grid equipment and determine the severity level of the service environment of the power grid equipment.

[0034] Terminal blocks, key components of the distribution network, fail after 15 years of service, aviation plugs fail after 20 years, and sealing rubber fails after 10 years. To evaluate the performance changes of the distribution automation terminal, the weight of their impact on the performance of the terminal, aviation plugs, and sealing rubber, was analyzed based on their functions. Specifically, the terminal block in the distribution automation terminal serves as a connector. Failure of its electrical conductivity will affect the normal operation of the distribution automation terminal, and thus has the greatest impact on the distribution automation terminal. Corrosion failure of aviation plugs increases contact resistance, causing heat generation. While this does not affect the function of the aviation plug, it will degrade the function of the distribution automation terminal. As a structural material, sealing rubber, while affecting the sealing effect upon failure, does not have any impact on the function of the distribution automation terminal. Therefore, its impact on the distribution automation terminal is very small.

[0035] Through the failure status analysis of various components, it can be seen that after 10 years of service, the sealing rubber fails, but it has no effect on the function of the distribution automation terminal, and the distribution automation terminal can still operate normally; after 15 years of service, the electrical conductivity of the terminal block contacts fails, which will cause the distribution automation terminal to malfunction and fail to operate normally; after 20 years of service, the contact resistance of the aviation plug will exceed the critical value. Although it will not affect the normal operation of the distribution automation terminal, it will increase the probability of failure of the distribution automation terminal.

[0036] The failure criterion of the distribution automation terminal is set according to the performance requirements of the distribution automation terminal. In this embodiment, after 15 years of service, the electrical conduction of the terminal block contacts fails, which will cause the distribution automation terminal to malfunction and fail to operate normally.

[0037] Based on the corrosion and aging status of materials used in power grid equipment over time, the corrosion and aging of power grid equipment at different service times are determined, and the service life of power grid equipment is evaluated. The severity level of the power grid equipment service environment is then classified based on the service life of the equipment. Service lives of 0-5 years, 5-10 years, 10-15 years, and 15-20 years correspond to severity levels S1, S2, S3, and S4, respectively.

[0038] The above analysis shows that the service life of distribution automation terminals in Qionghai is 10-15 years, so the corresponding severity level of the environment is S3.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. All modifications, equivalent replacements, improvements, etc. made to the above methods according to the present invention without departing from the basic technical concept of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for evaluating the severity level of the service environment of power grid equipment based on corrosion aging, characterized by The following steps are involved:

1. Determine the materials used for the main components of power grid equipment; 2. Obtaining corrosion aging state parameter data of various materials; the corrosion aging state parameters are corrosion amount, porosity and compression permanent set rate; 3. By measuring the key properties of materials in various corrosion and aging states and combining the impact of the corrosion and aging states on the key properties of the materials, a relationship model between the corrosion and aging states of various materials and their key properties is established. Based on the impact of changes in the key properties of the materials on the functions of their components, and combining the corrosion and aging states of the materials to obtain the functional changes of the components, the failure time of each major component is obtained; the key properties of the materials are conductivity, mechanical properties, sealing properties or insulation properties; 4. Based on the functions of the main components of the power grid equipment, the weight of the impact of each main component on the performance of the power grid equipment is analyzed; the power grid equipment failure criteria are set according to the performance requirements of the power grid equipment; the performance changes of the power grid equipment are evaluated to determine the severity level of the power grid equipment service environment; the severity level of the power grid equipment service environment is measured based on the service life of the power grid equipment, and the service life of the power grid equipment is 0-5 years, 5-10 years, 10-15 years, and 15-20 years, which correspond to the severity levels S1, S2, S3, and S4 of the power grid equipment service environment respectively; based on the corrosion and aging status of the materials used in the power grid equipment at different times, the corrosion and aging status of the power grid equipment at different service times is judged, and the service life of the power grid equipment is evaluated according to the above-mentioned power grid equipment failure criteria, and then the power grid equipment service environment severity levels are divided.

2. The method for evaluating the severity level of the service environment of power grid equipment based on corrosion and aging according to claim 1 is characterized by: Obtain corrosion aging parameter data of various materials through the National Materials Science Data Center or the National Materials Natural Environment Field Test Station.

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