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SUPERCONDUCTING CABLES
 Nexans develops a new generation of power cables (with relevant accessories) based on high temperature superconducting (HTS) wires and cryogenic lines technologies. These cables exhibit very low impedance characteristics and low in-line losses.
 The cable comprises superconducting tapes with very high current densities at or below 77 K. The conductor is integrated in a cryogenic line and cooled through a liquid nitrogen closed circuit. The power transmitted is three times higher than in the same volume of conventional underground cable. Several types of superconducting cables, with cold or warm dielectric, are available, depending upon the costumer requirements.
Nexans participates in a development project aiming at the installation of a 138 kV HTS cable with 574 MVA rated power in the Long Island Power Authority grid. This worldwide first installation at power transmission voltage level will be in service in 2006.
CRYOGENIC ENVELOPES FOR HTS CABLES
 CRYOFLEX( flexible, vacuum insulated cryogenic envelopes consist of two concentric, corrugated tubes. The tubes, together with their associated terminations and hardware, are assembled, leak tested and evacuated at the factory. It permits simple, safe and cost-saving installation at customer´s site.
 Design:
- Helically corrugated and longitudinally welded stainless steel tubes
- Protective outer PE-jacket
- Extremely low heat loss
- Diameter range from 10 to 300 mm
HTS MATERIALS
 BSCCO 2212 and B(P)SCCO 2223 precursor materials
Bismuth (Lead) Strontium Calcium Cuprate precursors are the starting materials for HTS wires and tapes. These materials, encapsulated in silver tubes, react to form the B(P)SCCO 2223 or BSCCO 2212 phases during thermo-mechanical wire fabrication.
 BSCCO 2212 Bulk Parts
Bulk parts of BSCCO 2212 are manufactured at Nexans SuperConductors using the proprietary Melt Cast Processed (MCP) method. This technique permits the production of a wide variety of shapes e.g. rods, tubes, plates, rings etc. Parts of up to 400 mm in diameter or 1000 mm in length can be rapidly cast and annealed to optimise properties.
Bulk rods and tubes are commercially used in current leads since 1995. In addition, tubes are employed in inductive fault current limitation and field trapping.
 Yttrium barium cuprate YBCO 123 and similar compounds
Bulk YBCO 123 offers the possibility of liquid nitrogen cooled shielding elements for motors, frictionless bearings and levitators while YBCO 123 targets are used to develop the next generation of conductors based on thin film technology.
HTS BSCCO 2212 TAPES
 Multifilamentary BSCCO 2212 tapes with lengths exceeding 1500 m are manufactured through a powder-in-tube process (PIT). A silver alloy sheath make tapes easy to handle. The PIT process provides the possibility to make coils by both the "wind and react" and the "react and wind" techniques. Insulated multi-tape conductors ready to use for coil winding are also available.
Tape typical characteristics:
 Dimensions : 0.22 x 4.0 mm²
Critical currents:: 800 A at 4.2 K (self field), 400 A at 4.2 K under 20 T, 450 A at 20 K
(self field)
Mechanical strength : 5 % decrease in critical current for 120 MPa
HTS COMPONENTS FOR CURRENT LIMITERS
Tubes are machined in to single and double spirals for magnetic field generation and resistive fault current limitation. The superconducting bifilar coils are the most powerful components for resistive limiters developed worldwide. These coils are protected by an electrical shunt and equipped with high voltage insulation. Implementation of the first fault current limiter (10kV, 10 MVA) into the energy grid for RWE Energy has just been celebrated in Netphen near Siegen (Germany).
CURRENT LEADS
Nexans SuperConductors has successfully partnered with ACCEL Instruments GmbH to offer fully engineered leads in the 50 A to 13kA range. We can design custom leads for wet and dry magnets and provide advice and help on system interface.
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