Development and Demonstration of a Fault Current Limiting HTS Cable to be Installed in the Con Edison Grid

The US Department of Homeland Security is currently funding the design, development and demonstration of an inherently fault current limiting HTS cable, called Secure Super Grids, under the Hydra project with Con Edison. The cable is 300 m long and is being designed to carry 96 MVA at a distribution level voltage of 13.8 kV. The cable will be built using cable system experience gained by AMSC and Ultera (a Southwire and nkt Cables joint venture) on previous projects. The underground cable will be permanently installed and energized in New York City in 2010. The project is led by American Superconductor who is teamed with Ultera and Con Edison. This paper describes the general goals and design criteria of the project. An overview of the concept of Secure Super Grids and advantages of this type of cable are presented in a grid-based network modeling. In addition, the design issues such as tailoring of the HTS wire to provide adequate thermal stability and electrical properties both under normal operation and during a fault are presented.