James T.M.,University of Swansea |
Schlosser M.,Institute for Technical Physics ITeP |
Lewis R.J.,University of Swansea |
Fischer S.,Institute for Technical Physics ITeP |
And 2 more authors.
Applied Spectroscopy | Year: 2013
An integrated concept for post-acquisition spectrum analysis was developed for in-line (real-time) and off-line applications that preserves absolute spectral quantification; after the initializing parameter setup, only minimal user intervention is required. This spectral evaluation suite is composed of a sequence of tasks specifically addressing cosmic ray removal, background subtraction, and peak analysis and fitting, together with the treatment of two-dimensional charge-coupled device array data. One may use any of the individual steps on their own, or may exclude steps from the chain if so desired. For the background treatment, the canonical rolling-circle filter (RCF) algorithm was adopted, but it was coupled with a Savitzky-Golay filtering step on the locus-array generated from a single RCF pass. This novel only-two-parameter procedure vastly improves on the RCF's deficiency to overestimate the baseline level in spectra with broad peak features. The peak analysis routine developed here is an only-two-parameter (amplitude and position) fitting algorithm that relies on numerical line shape profiles rather than on analytical functions. The overall analysis chain was programmed in National Instrument's LabVIEW;this software allows for easy incorporation of this spectrum analysis suite into any LabVIEW-managed instrument control, data-acquisition environment, or both. The strength of the individual tasks and the integrated program sequence are demonstrated for the analysis of a wide range of (although not necessarily limited to) Raman spectra of varying complexity and exhibiting nonanalytical line profiles. In comparison to other analysis algorithms and functions, our new approach for background subtraction, peak analysis, and fitting returned vastly improved quantitative results, even for "hidden" details in the spectra, in particular, for nonanalytical line profiles. All software is available for download. © 2013 Society for Applied Spectroscopy.
Holubek T.,Karlsruhe Institute of Technology |
Casalbuoni S.,Karlsruhe Institute of Technology |
Gerstl S.,Karlsruhe Institute of Technology |
Grau A.,Karlsruhe Institute of Technology |
And 4 more authors.
Physics Procedia | Year: 2012
Superconductive insertion devices (IDs) allow higher fields for a given gap and period length compared to the classical permanent magnet IDs. This technological concept enables an increase in the brilliance and/or the photon energy. The workhorse for superconducting magnets are multifilament NbTi wires, which are nowadays also used for superconducting insertion devices. Even higher magnetic fields can be reached by using a conductor with enhanced critical current density. Here, we propose a possible application for superconducting undulators, wound with NbTi wire with artificial pinning centers, developed by SupraMagnetics, Inc. We report the critical current characteristic, Jc(B), of a short wire measured in a liquid helium bath, and the load-line of a racetrack coil, designed to simulate the field configuration on the conductor as in a superconducting undulator. Based on the measured load line, we report on the simulations of the magnetic field on axis and of the spectrum in a third generation light source of a possible undulator wound with a wire having similar properties to the measured one. © 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of the guest editor.
Marino I.,Tecnalia |
Pujana A.,Tecnalia |
Sarmiento G.,Tecnalia |
Sanz S.,Tecnalia |
And 4 more authors.
Superconductor Science and Technology | Year: 2015
The offshore wind market demands a higher power rate and more reliable turbines in order to optimize capital and operational costs. The state-of-the-art shows that both geared and direct-drive conventional generators are difficult to scale up to 10 MW and beyond due to their huge size and weight. Superconducting direct-drive wind generators are considered a promising solution to achieve lighter weight machines. This work presents an innovative 10 MW 8.1 rpm direct-drive partial superconducting generator using MgB2 wire for the field coils. It has a warm iron rotor configuration with the superconducting coils working at 20 K while the rotor core and the armature are at ambient temperature. A cooling system based on cryocoolers installed in the rotor extracts the heat from the superconducting coils by conduction. The generator's main parameters are compared against a permanent magnet reference machine, showing a significant weight and size reduction. The 10 MW superconducting generator concept will be experimentally validated with a small-scale magnetic machine, which has innovative components such as superconducting coils, modular cryostats and cooling systems, and will have similar size and characteristics as the 10 MW generator. © 2016 IOP Publishing Ltd.
Sun J.,Institute for Technical Physics ITEP |
Sanz S.,Tecnalia |
Neumann H.,Institute for Technical Physics ITEP
IOP Conference Series: Materials Science and Engineering | Year: 2015
Superconducting generators show the potential to reduce the head mass of large offshore wind turbines. A 10 MW offshore superconducting wind turbine has been investigated in the SUPRAPOWER project. The superconducting coils based on MgB2 tapes are supposed to work at cryogenic temperature of 20 K. In this paper, a novel modular rotating cryostat was presented for one single coil of the superconducting wind turbine. The modular concept and cryogen-free cooling method were proposed to fulfil the requirements of handling, maintenance, reliability of long term and offshore operations. Two stage Gifford-McMahon cryocoolers were used to provide cooling source. Supporting rods made of titanium alloy were selected as support structures of the cryostat in aim of reducing the heat load. The thermal performance in the modular cryostat was carefully investigated. The heat load applied to the cryocooler second stage was 2.17 W@20 K per coil. The corresponding temperature difference along the superconducting coil was only around 1 K.