Project Overview

Objective

Utilities rely on extruded dielectric cable systems to meet growing demands for new underground transmission lines. This project intends to address several key research issues, including specific goals:

• Improving engineering-based design and installation procedures to accommodate electrical, mechanical, and thermal requirements for long-term performance, considering thermo-mechanical behaviors of cables and accessories as well as corrosive environments of buried or in-manhole components.
• Developing effective inspection and monitoring methods for cable system condition assessment.
• Achieving a better understanding of cable and component aging, failure mechanisms, and end-of-life criteria. Underground transmission engineers, designers, and managers can use the guidelines, methods, and technologies developed or assessed in this project to improve productivity and reduce costs of designing, installing, commissioning, testing, operating, and maintaining extruded dielectric cable systems. Engineers may use the improved understanding of the behavior of extruded dielectric cables under normal and emergency loading scenarios plus analytical or software-based tools to achieve effective and economical system designs. Operators and maintenance departments can deploy new inspection and monitoring methods and tools to obtain real-time and near-real-time information on cable system conditions.

Research Value

The new materials, devices, and methods produced in this project could improve the performance of extruded dielectric transmission cable systems to meet power system safety, reliability, and maintainability requirements and to contribute to improved technical standards. For example:

• Full-scale laboratory testing may validate and improve theoretical understanding of the thermo-mechanical behavior of extruded dielectric transmission cables. The results would support improved specifications and standardized designs, leading to higher system reliability, fewer circuit outages, and lower life-cycle costs.
• Development and deployment of advanced inspection and monitoring techniques may assist in asset management, improve utility operation efficiency, and increase system reliability.
• Investigation of corrosion inspection, assessment, and remediation methods and techniques for cable components in underground vaults addresses this emerging issue and may improve the design, inspection, maintenance, and protection of these components.
• Laboratory testing can deepen the industry’s understanding of system performance and help determine the end-of-life criteria of the system.

Planned 2025 Research

This project investigates methods and technologies for extruded dielectric transmission cable systems. Solutions are applicable to design, selection, installation, commissioning, testing, operation, and maintenance of these systems. The project seeks to answer research questions and address industry issues through the following activities:

Laboratory testing to validate engineering design models.

Laboratory testing to understand failure mechanisms and end-of-life.

Development and evaluation of innovative inspection and assessment tools, methods, and technologies.

Laboratory testing and field demonstration of developed or available diagnostic methods.