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A single 200-meter long high temperature superconducting (HTS) three-phase triaxial design cable is installed at the American Electric Power (AEP) Bixby substation in Columbus, Ohio. Findings reveal that the cable demonstrate steady state operation, high voltage operation, high voltage withstand and 110 kV impulse and overcurrent fault capability.

The development and testing of high temperature superconducting cables and terminations at the Oak Ridge National Laboratory is described.

Two 3-rn long, single-phase cables have been fabricated by Ultera from second generation (2G) superconductor wire supplied by American Superconductor. The first cable was made with two layers of 2G tape conductor and had a critical current of 5,750 A while the second cable had four layers and a critical current of 8,500 A. AC loss was measured for both cables at ac currents of up to 4 kArms. Ultera performed initial fault current studies of both cables in Denmark with limited currents in the range from 9.1 to 44 kA. Results from these tests will provide a basis for a 25-m long, three-phase, prototype cable to be tested at ORNL early next year and a 300-rn long, fault current limiting, superconducting cable to be installed in a Consolidated Edison substation in New York City. [ABSTRACT FROM AUTHOR]

The use of high temperature superconducting (HTS) materials for power transmission cable applications is being realized in several utility demonstration projects. Tape testing on short-sample cables is conducted to determine the suitability of HTS tapes for use in different cable designs. Testing includes deter- mining the DC critical current, ac loss and overcurrent behavior in a wound cable configuration. The short-sample cable configuration is similar in physical respects, such as winding diameter, winding pitch, application of dielectric, to a practical length cable. With more attention being paid to the short-circuit fault protection, the over-current pulse behavior of the cable will be tested thoroughly. The temperature history of the cable in the radial direction and the re-cooling of the cable will be monitored and compared with a model calculation. This paper describes the testing and results from one such series of tests of a short-sample cable made with copper laminated HTS tapes for use in future projects. [ABSTRACT FROM AUTHOR]

The Ultera/ORNL team have built and tested 3-m and 5-m triaxial cables rated at 3 and 1.3 kA-rms, respectively. The three concentric superconducting phases are made of BSCCO-2223 HTS tapes, separated by layers of cold-dielectric tapes. A copper braid is added as the grounding shield on the outside of the three active phases. Tests of these cables were performed at temperatures ranging from 70 to 84 K. AC loss data reconfirmed the previous result on a 1.5-m prototype cable that the total 3-phase ac loss is about the sum of the calculated ac losses of the three concentric phases. These and other test results of the 1,3 and 3 kA cables will be used to construct a second S-m triaxial cable rated at 3 kA-rms, 15 kV. Preliminary test results supporting this new cable and the associated termination are summarized. [ABSTRACT FROM AUTHOR]

The impact of Ni-5at%W substrates on ac loss and inductance of HTS cables was examined. Two 1.2-m prototype cables were made with stainless steel laminated BSCCO tapes and were wound on a 25.4 mm diameter former. Each cable consisted of two layers of 15 BSCCO tapes wound at opposite lay angles and has an estimated critical current of 3000 A at 77 K. One cable had four additional layers of 4.8 mm wide Ni-Sat % W tape co-wound with the BSCCO tapes to simulate a commercial second generation IITS cable. The Ni-5at%W tapes had the same width as the BSCCO and a thickness of 50 microns. Through the use of a coaxial copper ground, the cable inductance was measured at room temperature and liquid nitrogen (77 K) using high frequency rf measurement techniques. Experimental results for the cable inductance and ac loss were compared against numerical calculations to determine the significance of the Ni-5at%W substrate contribution. Results indicate that inductance and ac loss changes from these substrates in commercial cables should be small. [ABSTRACT FROM AUTHOR]