top of page

Verdant Experts

Public·12 Verdant Expert
Yefim Alekseev
Yefim Alekseev

Selection and dimensioning of high-voltage insulators for polluted conditions - Part 1: Definitions, information and general principles


IEC 60815: Guide for the selection and dimensioning of high-voltage insulators for polluted conditions




High-voltage insulators are essential components of any electrical system that operates at high voltages. They provide electrical insulation and mechanical support for conductors and equipment. However, in polluted environments, such as industrial areas, coastal regions, or desert zones, the performance of insulators can be severely affected by the accumulation of contaminants on their surface. This can lead to flashovers, power outages, and damage to the system.




IEC 60815: Guide for the selection and dimensioning of high ....13



To prevent these problems, it is important to select and dimension the insulators according to the specific pollution conditions of each site. This is where the IEC 60815 series of standards comes in handy. These standards provide guidance and recommendations for the selection and dimensioning of high-voltage insulators for polluted conditions.


What are the main parts of the IEC 60815 series?




The IEC 60815 series consists of five parts, covering different types of insulators and systems:


  • Part 1: Definitions, information and general principles. This part provides the basic concepts and terminology related to pollution and insulators, as well as general information on how to assess the pollution severity and select the appropriate insulator type and dimension.



  • Part 2: Ceramic and glass insulators for a.c. systems. This part provides specific guidance and recommendations for the selection and dimensioning of ceramic and glass insulators for alternating current systems operating at voltages above 1 kV.



  • Part 3: Polymer insulators for a.c. systems. This part provides specific guidance and recommendations for the selection and dimensioning of polymer insulators for alternating current systems operating at voltages above 1 kV.



  • Part 4: Ceramic and glass insulators for d.c. systems. This part provides specific guidance and recommendations for the selection and dimensioning of ceramic and glass insulators for direct current systems operating at voltages above 1 kV.



  • Part 5: Polymer insulators for d.c. systems. This part provides specific guidance and recommendations for the selection and dimensioning of polymer insulators for direct current systems operating at voltages above 1 kV.



How to use the IEC 60815 series?




The IEC 60815 series is intended to be used as a reference tool for engineers, designers, manufacturers, operators, and maintenance personnel involved in the selection and dimensioning of high-voltage insulators for polluted conditions. The standards provide a systematic approach to evaluate the pollution severity of a site, select the most suitable insulator type and material, and determine the required creepage distance and other relevant dimensions.


The standards also provide examples of calculation methods, test procedures, and data tables to facilitate the application of the recommendations. However, the standards do not prescribe specific values or solutions for every situation, as these may vary depending on local factors and operational experience. Therefore, the standards should be used with professional judgement and in conjunction with other relevant standards and technical documents.


What are the benefits of using the IEC 60815 series?




By using the IEC 60815 series, you can achieve several benefits for your high-voltage system, such as:


  • Improving the reliability and safety of your system by reducing the risk of flashovers and failures due to pollution.



  • Optimizing the performance and efficiency of your system by selecting and dimensioning the insulators according to the actual pollution conditions.



  • Enhancing the durability and lifespan of your insulators by choosing the most suitable material and design.



  • Saving costs and resources by avoiding over or under design of your insulators.



If you want to learn more about the IEC 60815 series, you can visit the official website of the International Electrotechnical Commission (IEC), where you can purchase and download the standards in different languages.


What are the main factors affecting the pollution performance of high-voltage insulators?




The pollution performance of high-voltage insulators depends on several factors, such as:


  • The type and amount of pollutants present in the environment, which can be classified into natural (e.g. salt, sand, dust) or artificial (e.g. industrial emissions, agricultural chemicals) sources.



  • The climatic conditions of the site, such as temperature, humidity, wind, rainfall, and solar radiation, which influence the deposition, accumulation, and removal of pollutants on the insulator surface.



  • The electrical stress on the insulator, which is determined by the system voltage, the configuration of the conductors and equipment, and the presence of transient overvoltages.



  • The characteristics of the insulator material and design, such as the hydrophobicity, surface roughness, shape, size, and arrangement of the sheds and housing.



All these factors interact with each other and affect the formation and development of pollution layers on the insulator surface, which can reduce the insulation resistance and increase the leakage current. When the leakage current reaches a critical value, a flashover can occur across the insulator.


How to assess the pollution severity of a site?




To select and dimension the appropriate insulators for a site, it is necessary to assess the pollution severity of the environment. The IEC 60815 series provides two methods for this purpose:


  • The site tests method, which involves measuring the equivalent salt deposit density (ESDD) and/or the non-soluble deposit density (NSDD) on test insulators installed at the site for a certain period of time. These parameters reflect the amount and nature of pollutants deposited on the insulator surface.



  • The simplified method, which involves estimating the pollution severity based on environmental and operational data collected from the site or from similar sites. This method uses a classification scheme that assigns a pollution severity level (from light to very heavy) according to various criteria such as pollution sources, climate factors, electrical stress, and insulator performance.



Both methods have advantages and limitations, and should be used with caution and experience. The site tests method provides more accurate and reliable results, but it is also more time-consuming and costly. The simplified method provides a quick and easy estimation, but it is also more subjective and uncertain. Therefore, it is recommended to use both methods in combination and to compare their results with existing operational experience.


How to select the type and material of high-voltage insulators for polluted conditions?




The IEC 60815 series provides guidance and recommendations for the selection of the type and material of high-voltage insulators for polluted conditions. The main types of insulators are:


  • Cap and pin insulators, which consist of one or more ceramic or glass units connected by metal fittings.



  • Long rod insulators, which consist of a single ceramic or glass unit with metal end fittings.



  • Composite insulators, which consist of a fiberglass core with a polymeric housing and metal end fittings.



  • Hybrid insulators, which consist of a combination of ceramic or glass units and polymeric housing.



The main materials of insulators are:


  • Ceramic (porcelain or glass), which has high mechanical strength, good electrical properties, and resistance to ageing and corrosion.



  • Polymer (silicone rubber or ethylene propylene rubber), which has high hydrophobicity, flexibility, and resistance to UV radiation and tracking.



  • Semi-conducting glaze, which is a coating applied on ceramic insulators to reduce the surface resistance and improve the voltage distribution.



The selection of the type and material of insulators depends on several factors, such as the pollution severity, the system voltage, the mechanical load, the environmental conditions, the maintenance requirements, and the cost-effectiveness. The IEC 60815 series provides tables and charts to help compare the advantages and disadvantages of different types and materials of insulators for different applications.


How to determine the required creepage distance and other dimensions of high-voltage insulators for polluted conditions?




The creepage distance is the shortest distance along the surface of an insulator between two conductive parts. It is an important parameter that affects the pollution performance of an insulator. The higher the creepage distance, the lower the risk of flashover due to pollution.


The IEC 60815 series provides methods and formulas to determine the required creepage distance of high-voltage insulators for polluted conditions. The required creepage distance depends on several factors, such as the pollution severity, the system voltage, the insulation level, the type and material of insulator, and the safety margin. The IEC 60815 series also provides tables and charts to help select standard values of creepage distance for different types and materials of insulators.


In addition to the creepage distance, other dimensions of high-voltage insulators for polluted conditions are also important, such as the diameter, the length, the spacing, and the shape of the sheds and housing. These dimensions affect the surface area, the wetting angle, the self-cleaning ability, and the voltage distribution of an insulator. The IEC 60815 series provides guidance and recommendations for determining these dimensions according to the type and material of insulator.


Conclusion




The IEC 60815 series is a valuable resource for anyone involved in the selection and dimensioning of high-voltage insulators for polluted conditions. The standards provide comprehensive and practical guidance and recommendations for assessing the pollution severity of a site, selecting the most suitable type and material of insulator, and determining the required creepage distance and other relevant dimensions. By following the standards, you can improve the reliability, safety, performance, efficiency, durability, and cost-effectiveness of your high-voltage system. 4e3182286b


https://soundcloud.com/yeisygetmezm/warcraft-3-frozen-throne-patch-131-download-work-crack

https://soundcloud.com/busroruptro1976/bandicam-cracked-2022

https://soundcloud.com/kaakaelmataf/clarity-v2-free

About

Welcome to the group! You can connect with other members and...

Verdant Expert

bottom of page