A dc transmission cable prototype using high-temperature superconductors

Abstract

This paper gives the results from a recent collaboration between BICC Cables Ltd, its Italian subsidiary Ceat Cavi srl, and Ansaldo Ricerche srl on the design and testing of a high-temperature superconducting dc transmission cable prototype. The cable was designed to carry 10 000 A at 40 kV, operating at 40 K. Qualification testing was carried out from 4.2 K up to 40 K. At an operating temperature of 31 K the prototype cable had a current capacity of 11 067 A (the largest dc current reported in a high-temperature prototype to date), which represents a tenfold increase in current over a conventional 1000 mm 2 copper cable.

Superconducting Lines for the Transmission of Large Amounts of Electrical Power Over Great Distances: Garwin–Matisoo Revisited Forty Years Later

“…The design is an interesting one, targeting a 400 km European "ring buss" with a 400 MW, 40 kV, 10 kA capacity with cold He gas at 4.2 K blown in one end and warming to 40 K at the other, well within the critical parameter limits of Bi-2223 throughout that range [15].…”

“…Equation (1) in the limit where the of ac modulation is small compared to the background current becomes (2) where R is the effective radius of a solid round wire of cross-sectional annular area given in Table II (6.62 ) or 1.45 cm, the critical current, 15 , the rms ripple current, which we take to be 1% or 1000 A (actual ripple can be substantially reduced by proper filtering in the inverter/converter stations) and is the ripple frequency, 360 Hz for 6-phase ac input. Under these conditions, we obtain , a quite tolerable value readily accommodated by the refrigeration system.…”