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A conceptual design of a superconducting rotor based on Mg[B.sub.2] conductor is designed for a synchronous machine. The overall machine design and parameters have shown a promising High Temperature Superconducting (HTS) flux pump excited double-helix design for synchronous machines.

An improved version of the focusing magnet for a Heavy Ion Fusion (HIF) accelerator is designed, built and tested in 2002-2003. The features of the new design, fabrication and test results are discussed.

The fabrication and testing of three dipole magnets designed for use as correction coils in the planned Superconducting Super Collider are discussed. All three were wound using the direct wind process. The three, with the exception of a Bondall magnet, were subjected to thermal cycling and quench detection tests. Except for four training quenches, both magnets that underwent both tests demonstrated performance that exceeded Collider specifications by a 16% margin.

A dual-solenoid magnet system was designed and fabricated for characterizing high temperature superconducting tapes and coils. The magnet coils were made of copper wire and were fabricated using a new winding approach, which enables multi-layer and epoxy-free coils. It was demonstrated that the magnet system provided a uniform AC magnetic field in radial and axial orientations on superconducting rings fabricated from 40 mm wide second generation (2G) high temperature superconducting tape. AC losses were measured on the superconducting rings with variable frequency AC magnetic field applied in both the radial and axial orientations. The versatility of the magnet and the AC loss measurement system is useful for generating the necessary AC loss data for applications such as transformers, inductive fault current limiters, and magnetic shields. [ABSTRACT FROM PUBLISHER]

Superconducting synchronous machines require Direct Current (DC) excitation for their field windings which can be achieved via brushless exciters or by direct connection to current leads. However, the resulting heat loads limit their application. An excitation system consisting of a High-temperature Superconducting (HTS) full wave rectified flux pump eliminates these issues and enables operation at high currents. [ABSTRACT FROM AUTHOR]

A heavy ion driver for inertial fusion will accelerate an array of beams through common induction cores and then direct the beams onto the DT target. An array of quadrupole focusing magnets is used to prevent beam expansion from space charge forces. In the array, the magnet fields from the coils embracing the beams are coupled, which reduces the cost of superconductor and increases the focusing power. The challenges in designing such an array are meeting the strict requirements for the quadrupole field inside the beam pipes and preventing stray fields outside. We report our optimization effort on designing such an array and show that 3 × 3 or larger arrays are feasible and practical to build with flat racetrack coils. [ABSTRACT FROM AUTHOR]

The Heavy Ion Fusion (HIF) program is progressing through a series of physics and technology demonstrations leading to an inertial fusion power plant. The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is exploring the physics of intense beams with high line-charge density. Superconducting focusing quadrupoles were developed for magnetic transport studies at the HCX. A baseline design was selected following several pre-series models. Optimization of the baseline design led to the development of a first prototype that achieved a conductor-limited gradient of 132 T/m in a 70 mm bore, without training, with measured field errors at the 0.1% level. Based on these results, the magnet geometry and fabrication procedures were adjusted to improve the field quality. These modifications were implemented in a second prototype. In this paper, the optimized design is presented and comparisons between the design harmonics and magnetic measurements performed on the new prototype are discussed. [ABSTRACT FROM AUTHOR]

An improved version of the focusing magnet for a Heavy Ion Fusion (HIF) accelerator was designed, built and tested in 2002-2003. This quadrupole has higher focusing power and lower error field than the previous version of the focusing quadrupoles successfully built and tested in 2001. We discuss the features of the new design, selected fabrication issues and test results. [ABSTRACT FROM AUTHOR]

In a heavy ion fusion driver, arrays of superconducting quadrupoles will transport parallel beams through a sequence of induction acceleration cells. The development of such arrays is a unique and challenging task. Since magnetic transport is one of the most expensive subsystems, economy of fabrication is a primary consideration. A compact design is essential to limit the size and cost of induction cores. Special edge coils have to be implemented to adjust the field in outer cells and terminate the magnetic flux. The development of superconducting magnets for both near term experiments and the ultimate driver application is actively pursued by the U.S. Heavy Ion Fusion Program. The main parameters and requirements are discussed, and the R&D status and plans are presented. [ABSTRACT FROM AUTHOR]

Four NbTi superconducting prototype quadrupole magnets have been built for the High Current Transport Experiment (HCX) as part of the multi-beam heavy-ion fusion research activity, led by the Lawrence Berkeley National Laboratory (LBNL). MIT performed quench training and ramp rate tests of the two prototype magnets that were designed and built by the Advanced Magnet Lab, Inc. (AML), based on a novel concept featuring cable-in-groove and multi-layer stacking. Both magnets are splice-free without inter-layer or inter-quadrant joint. Each coil was wound with a continuous NbTi round cable, placed in precise grooves machined in G-11 plates. The two magnets differ in their cable construction and their coil and yoke configuration. Each magnet was tested more than once in liquid helium bath with a room temperature thermal cycle between cold tests. This paper describes the results of the performance tests as well as the instrumentation and the quench protection system. Possible improvements for future coil winding are discussed. [ABSTRACT FROM AUTHOR]

Describes a proposed superconducting solenoid magnets with a superimposed dipole field for the cooling channel for a future high luminosity muon collider. Bending of the magnets; Centerline radius; Aperture; Use of on-axis solenoidal field; Generation of dipole field by tilting the winding planes of the solenoid coil.