Conceptual design and cooling strategies of current lead for superconducting power transmission applications

The superconducting power transmission applications requires current lead for transferring electric current from room temperature to the cryogenic environment. The current lead being made from a normal conductor requires special cooling as high density current is passed from it. In this paper, a generalized conceptual design of the current leads for all the superconducting applications is presented. This design of the current lead is derived from the past designs used in superconducting applications. A heat balance equation that governs the quenching of the lead is derived considering all the modes of heat infiltration into the lead. The whole lead has been divided into different parts so that each aspect can be emphasized upon to achieve maximum current carrying capacity with minimum cooling load. The cooling strategies adopted for maintaining the cryogenic environment inside the lead with minimum cooling load on the refrigerator are also discussed.