Improvement of Mechanical and Electrical Strength of the Cap-and-Pin Type String Insulators

电力传输系统的功能和可靠性在很大程度上依赖于将导线、杆塔和地面相互隔离的绝缘体。绝缘子在很长一段时间内承受高机电应力。绝缘子必须长期保持其物理性能和机械强度不变。绝缘子的良好性能源于使用合适的材料、合适的设计和现代制造技术。绝缘子的机械和电气特性受静态机械载荷(悬挂或张力)、动态机械载荷(短路、风和导线舞动)、温度和高电场的影响。机械负荷、温度和高电场会降低绝缘子的性能，这将危及输电线路系统输送的电能的质量和可靠性。理想的情况是，输电线路绝缘子应该定期检查，以确保最大的运行可靠性。然而，由于运行中的绝缘子数量很多(例如，北美超过1.5亿个瓷绝缘子)，这对公用事业公司来说是不现实的。多年来，改进绝缘子设计，使其更耐用，使其使用寿命更长，一直是人们感兴趣的话题。通过提高绝缘子的机械、热和电气强度，可以提高绝缘子的耐压能力。该研究项目的目的是与Powertech高压实验室合作，介绍一种基于有限元方法和电气和机械试验标准化方法的高压绝缘子设计新方法。这项研究的结果将提供绝缘子的优化设计，从而提高其机械和电气耐久性。改进后的设计将提升Powertech Labs在高压绝缘子制造行业的竞争力和影响力。

Functionality and reliability of electric power transmission systems highly depend on insulators that isolate conductors from each other, the towers, and the ground. The insulators undertake high electrical mechanical stresses for long periods of time. The insulators must maintain their physical properties and mechanical strength over long periods without deterioration. The good performance of insulators results from using proper materials, suitable design, and modern manufacturing technology. The mechanical and electrical characteristics of an insulator are affected by the static mechanical loads (suspension or tension), dynamic mechanical loads (short circuit, wind, and conductor galloping), temperature, and high electric field. The mechanical loads, temperature, and high electric field can degrade the insulators' performance, which will compromise the quality and reliability of the electric power delivered by the transmission line system.Ideally, transmission line insulators should be inspected regularly to ensure maximum service reliability. However, due to the large number of insulators in service (e.g. over 150M porcelain insulators in North America), this is not practical for utility companies. Improvement of insulator design to make them durable for longer life of service has been a topic of interest for many years. The withstand voltage of insulators will be improved by increasing the mechanical, thermal, and electrical strength. The purpose of the proposed research project is to introduce a new method to design high voltage insulator based on finite element method (FEM) and standardized methodologies of electrical and mechanical tests in partnership with Powertech High Voltage Laboratory. The outcome of this research will provide an optimized design for insulators that will improve both their mechanical and electrical withstand. The improved design will enhance the competence and presence of Powertech Labs in high voltage insulator manufacturing industry.