A Critical Review on cooling techniques used in High Temperature Superconducting (HTS) Cables

Abstract

Superconducting cables have the potential to enhance the advancements in technology innovatively. However, the potential is limited with conventional geometries, materials, stability, sensitivity, cooling efficiencies of the system and cost. HTS cables are prominent for high current transmission compares with conventional cables and are internally cooled by the cryogenic coolants to retain its superconductivity. The cooling efficiency depends on the length of the cable, geometry and transport current. One or more refrigeration systems should be terminated because of the heat loads on the HTS cable such as AC losses from the superconducting tape, heat leaks from the ambient and heat intrusions from the ends of leads at terminations. BSCCO and YBCO tapes are mostly frequently used in HTS cables.

In this context, for cooling of HTS cable selection of a suitable coolant is necessary and coolant with best thermopyhsical properties are should be preferred. Different methods of cooling are developed such as counter-flow cooling, novel cooling scheme, conduction cooling etc. It is important to investigate the pressure drop, friction factor, cooling capacity and pumping power as the cryogenic coolant flow through the corrugated former in HTS cables to retain superconductivity of HTS tape. However, flow in the computational domain is turbulent various turbulent schemes are to be investigated. The methods of cooling, methodology for finding the cooling capacity and pumping power required for cooling the HTS cable are given in the literature.