Abstract: A cable termination comprising an upper cryostat chamber containing a liquid cryogen and a lower cryostat chamber containing a gaseous cryogen to maintain dielectric integrity and thermal management of an electric connection. A gaseous cryogen recirculation system may cause the gaseous cryogen to flow through the lower cryostat chamber and a power cable enclosure.

Abstract: A heat sink and method for gaseous cooling of superconducting power devices. Heat sink is formed of a solid material of high thermal conductivity and attached to the area needed to be cooled. Two channels are connected to the heat sink to allow an inlet and an outlet for cryogenic gaseous coolant. Inside the hollow heat sink are fins to increase metal surface in contact with the coolant. The coolant enters through the inlet tube, passes through the finned area inside the heat sink and exits through the outlet tube.

Abstract: A heat sink and method for gaseous cooling of superconducting power devices. Heat sink is formed of a solid material of high thermal conductivity and attached to the area needed to be cooled. Two channels are connected to the heat sink to allow an inlet and an outlet for cryogenic gaseous coolant. Inside the hollow heat sink are fins to increase metal surface in contact with the coolant. The coolant enters through the inlet tube, passes through the finned area inside the heat sink and exits through the outlet tube.

Abstract: A cable termination utilizing liquid and gaseous cryogen. The liquid cryogen maintains cryogen temperatures of all dielectric surfaces exposed to gaseous cryogen and to high voltage potential. The invention further includes capacitive grading, minimizing the electric field on the surface of the bushing in the vapor phase of the cryogen used in the liquid cryogen compartment. The cross-section of the conductor within the cable termination is adjusted along its axis enabling thermal optimization for reduction in the loss of liquid cryogen. Heat sink, for helium gas cooling of superconducting power devices, is surrounded by a metal of high thermal conductivity and placed near the area needed to be cooled. Cryogenic gaseous coolant flows through two tubes connected to the heat sink. Fins inside heat sink increase metal surface in contact with the coolant. The coolant flows from first tube, passes through the finned are and exits through the second tube.