Development and demonstration of a long length HTS cable to operate in the long island power authority transmission grid

The US Department of Energy is currently funding the design, development and demonstration of the first long length, transmission level voltage, cold dielectric, high temperature underground superconductor power cable. The cable is designed for permanent installation in the Long Island Power Authority (LIPA) grid and is being designed to carry 574 MVA at a voltage of 138 kV. The project is led by American Superconductor and the team is comprised of Nexans, Air Liquide and LIPA. This paper describes the goals of the project, and an overview of the cable design, refrigeration system and site system requirements. It also includes a discussion of the influence of transmission network requirements, such as fault currents, on the design of the cable.