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The article discusses the design and importance of the second-generation (2G) High Temperature Superconducting (HTS) wires for coil applications. Results suggest the viability of 2G HTS wire in coil applications as the 2G solenoid coil with a 5cm inner diameter is able to achieve 1.5 T at 64 K.

The progress and the performance of the development of the Second Generation (2G) high temperature superconducting (HTS) wires at the American superconductor are evaluated. The approach used is extremely cheap and leads to the manufacturing of excellent quality of wires.

A new design for the development of the Second Generation High Temperature Superconductor (2G HTS) multifilamentary wires is explained. The striation method imparts better properties to the wires, hence making them useful for several AC applications.

The development of a demonstration high temperature superconducting magnet for use in minesweeping applications is discussed.

The progress in the development of high efficiency high temperature superconducting motors is reported. The goals of the development project inslude saving half the losses of conventional motors in a package with half the volume. The status of a 1,000 hp motor development which is part of a Phase II effort is described. The motor fully represents the design issues to be addressed in the 5,000 hp motor also to be developed in Phase II.

A 5 kJ Superconducting Magnetic Energy Storage (SMES) magnet was designed, fabricated and tested by American Superconductor Corp for Germany's Gesellschaft fur Innovative Energieumwandlung und Speicherung. The high temperature superconducting (HTS) SMES is made up of a solenoidal coil base on a reacted silver-sheathed BiPb2Sr2Ca2Cu3O conductor. The magnet was tested and successfully operated, verifying the approach of cooling HTS magnets with G-M type cryocoolers.

A calorimetric device is proposed for alternating current (AC) loss measurements in Bi-2223 conductors with external field oriented perpendicular to the tape width. AC losses are partly attributed to the AC magnetic fields perpendicular to the conductor's wide face. The device was found to be accurate in estimating interstrand or interfilament coupling losses. It was successfully applied to long length twisted multifilamentary conductors.

In this study we examined ac losses in a multifilamentary Bi-2223/Ag superconducting tape carrying ac transport current. The tape consisting of 85 filaments was helically wound to a single-layer coil. The losses were measured at 77 K in the frequency range from 1 Hz up to 250 Hz. Current amplitudes [I.sub.p] were ranging from i=[I.sub.p]/[I.sub.c]=0.6 to 1.5, critical current [I.sub.c]=15.4 A determined by the standard 1 [[micro]volt]/cm static electric field criterion. The roles of special loss components were considered: hysteresis, flux-creep, coupling and eddy current losses. Hysteresis losses due to the self-field of the ac transport current were found to dominate when i[less than or equal to]1.1. Resistive losses dominated when i>1.2. In the hysteretic regime, the higher the frequency, the smaller the losses per cycle.

The stability of a high-temperature superconducting (HTS) magnet was investigated. Specifically, the coil, which was built by American Superconductor Corp., was tested for stability and normal zone propagation in background fields up to 2.5 T at temperatures between 4.2 K to 77 K. According to results, the Bi-2223 solenoidal magnet generates a central field of 1.1 T at 4.2 K. Its HTS superconductors' thermal stability margin over the entire range is more than 150 J/cm.

Application of High Temperature Superconductors (HTS) to devices requires a detailed understanding of the effects of temperature, magnetic field and orientation of magnetic field on the critical current density. Measurements of the critical surface of PbBSCCO were made on long lengths of fully reacted multi-filamentary wire wound into solenoids. These react & wind coils were tested in magnetic fields to 20 tesla and temperatures from 1.8 K to 77 K. Overall current densities of 200-300 A/[mm.sup.2] were achieved at fields of 20 T. The effect of high electromagnetic forces on performance of high temperature superconducting (HTSC) coils is analyzed and compared with analytical models for the HTSC conductor and coil winding.

A passive voltage-current simulator developed by the National Institute of Standards and Technology (NIST) is used to compare the accuracy of critical current measurements and the power-law behavior of high temperature superconductors (HTS). In this study, critical current measurements made from four data acquisition and analysis systems are compared with those carried out at NIST. This paper also discusses various measurement techniques, methods of calculating critical current, and n-values. The V-I simulator is believed to be an advancement towards defining the standards for critical current measurements and ensuring the traceability of results at different test facilities.