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High power density applications require special treatment in design optimization. Among the critical questions is how the working torque angle will change through an optimization analysis. We present a new method for computing and using the synchronous reactance that accounts for the torque angle in the midst of complex parameter changes. The challenge is to tally this effect along with the load power factor into a variable metric optimization. Our new technique both computes this reactance under heavy saturation and integrates it into the machine design. The technique also covers appropriate stator current excitation densities in transient and steady-state excitation. Index Terms--Deterministic, optimization, reactance, superconducting, synchronous.

The conceptual design of the High Temperature Superconducting (HTS) generator for Mobile Radar applications is described. Its power system is composed of a generator, power conditioning electronics and a diesel engine. The cryogenic cooling of the generator and the power electronics result in substantial improvements in performance, system efficiency and power density. The total losses and efficiency are presented.

Practical issues for two distinct coil designs for Maglev are considered. Comparisons are made between designs with NbTi conductor in liquid helium pool boiling, and a [Nb.sub.3]Sn cable-in-conduit conductor (CICC) with forced flow. The issues considered include stability, vibrations induced by the interaction with guideway coils, reliability, heat leak, safety, manufacturability and the magnets' interface to the on-board cryosystem. Results of the study are reported listing the advantages and disadvantages of each design as they relate to the overall maglev vehicle and guideway system.

A superconducting magnet has been designed for use aboard a magnetically levitated vehicle. The design provides null-flux levitation with propulsion coming from a locally commutated linear synchronous motor. It covers magnet coil design, conductor selection, cryostat design and refrigeration issues. The work is part of a collaborative effort between the Dept of Transportation, Army Corps of Engineers and Dept of Energy.

All over the world there is a growing need for current limiting devices in electrical networks with steadily increasing power demands and fault currents. Production of YBCO coated conductors (CCs) paves the way for the economic viability of superconducting fault current limiters (FCLs) both in power distribution and transmission networks. In a cooperation between AMSC and Siemens the limiting capability of YBCO CCs has been investigated and was demonstrated in a successful laboratory test of a 2.2 MVA medium voltage FCL. This device is based on bifilar coils as switching elements and corresponds to one phase of a 3-phase FCL designed for the 13kV-class distribution voltage level. In more than 40 switching tests at voltages up to 7.7 kV the device showed excellent limiting performance. Presently this cooperation has entered a new DOE funded joint project that encompasses the design, construction and test of a 115 kV FCL for power transmission within a time frame of 4-5 years and additional partners. AMSC as the project leader is responsible for wire manufacturing, system integration and cryogenics. Siemens' main task is switching modules development, Nexans contributes the high voltage terminations and Los Alamos National Lab investigates AC losses. Installation and testing are planned for a Southern California Edison substation. A project overview and progress under the first phase will be reported. [ABSTRACT FROM AUTHOR]

A 5 MW, 230 RPM, 6-pole high temperature superconductor (HTS) ship propulsion motor is presently under test at the Center for Advince Power Systems (CAPS). This paper provides a summary of the key design features of the motor, predicted performance, factory test results and extended test results to date at CAPS. This motor was designed and built under the U.S. Navy's Office of Naval Research (ONR) funding (Contract #N00014-02-C- 0190) to address the next generation of electric ship propulsion systems. HTS motors are characterized by high power density, quiet operation and high efficiency. HTS air-core motors have unique electrical characteristics and therefore require dynamic testing to validate all modes of operation. The test program at CAPS is designed to address dynamic performance and simulation of this class of propulsion motor. The motor has been operated at 5 MW load for over 3 hours at CAPS. [ABSTRACT FROM AUTHOR]

Presents information on the use of an individualized vocabulary acquisition, in an effort to enhance the vocabulary among students. Identification of the premise behind the acquisition; Detailed information on the use of a hypertext software package, a word processing package and a software dictionary.