Jacopo Bongiorno, Andrea Mariscotti
The recordings of the pantograph voltage and current waveforms across Italian and French high speed railway lines (both Autotransformer 2x25 kV 50 Hz systems) are analyzed to estimate some Power Quality indexes: harmonic spectra, harmonic distortion, displacement factor and fundamental component, in various rolling stock operating conditions. These indexes, that define the electrical interface between the rolling stock and the power supply, are all relevant in order to assess both the impact of the rolling stock on the network and the suitability of the latter to ensure agreed performances...
TC4 Symposium 2014
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· 2014
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Regis Pinheiro Landim, Waldemar Guilherme Kürten Ihlenfeld
Traditional calibration of dc voltage high accuracy digital voltmeters (DVMs) using conventional and Programmable Josephson Voltage Standards at INMETRO show improvements between 73.7 % and 98.3 % when compared with a regular calibration technique. Some calibration results as well as DVM linearity and gain drift analysis (up to 10 V range) are presented and discussed in this paper.
TC4 Symposium 2014
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Věra Nováková Zachovalová, Martin Šíra, Pavel Bednář
This paper describes a new generation of cage-type ac/dc current shunts from 30 mA up to 10 A developed using a lumped circuit element model. Comparison of the calculated and measured values shows agreement better than 6 %Omega;/%Omega; in the ac-dc difference at frequencies up to 100 kHz.
TC4 Symposium 2014
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Umberto Pogliano, Bruno Trinchera, Danilo Serazio
Resistive dividers find application in instrumentation because they allow fast and precise scaling-down of the applied signal input to an appropriate level of the processing electronics. Furthermore, among the applications where both wideband and accuracy requirements are demanding, resistive dividers employed as fixed-voltage ratio standards are widely used. Recently, at INRIM, coaxial voltage dividers suitable to be used in specific tasks of EU and National co-founded projects have been developed. Series-parallel type of dividers have been studied and built. Besides, methods for adjusting...
TC4 Symposium 2014
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Pier Paolo Capra, Flavio Galliana, Marco Lanzillotti
A temperature controlled 1 Ω – 10 kΩ Standard resistors setup was developed at National Institute of Metrological Research, (INRIM). The aim of this realization was the involvement of the setup resistors in the traceability transfer process to high accuracy multifunction electrical instruments used in Secondary Electrical Calibration Laboratories or even their use as primary Standards in high level Laboratories or Institutes. The 1 Ω – 10 kΩ Standards are formed respectively by two 10 Ω and 100 kΩ parallel connected resistors nets inserted in a temperature controlled aluminium box....
TC4 Symposium 2014
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Dragana Popovic Renella, Sasa Dimitrijevic, Sasa Spasic, Radivoje S. Popovic
The new digital teslameter system incorporates a 3-axis Hall probe, analog electronics based on the spinning-current technique, 24-bit analog-to-digital converter, computer, and 7-digit touch-screen display. The Hall probe is a single silicon chip with monolithically integrated horizontal and vertical Hall magnetic sensors and a temperature sensor. The Hall sensor chip is encapsulated in a robust ceramic package, a version of which is only 250μm thick. The spinning-current eliminates most of the Hall probe offset, low-frequency noise, and the planar Hall voltage. The errors due to the Hall...
TC4 Symposium 2014
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Pasquale Arpaia, Marco Buzio, O. Köster, Stephan Russenschuck, Giordana Severino
A method for calibrating the radius of rotating, harmonic sensing coils is proposed that allows relaxing constraints on alignment and field errors of the reference quadrupole magnet. Radius calibration considering roll angle misalignment between the measurement bench, the magnet, and the motor-drive unit is studied first. We then study the calibration error when a harmonic field error of higher order is present in the calibration magnet. This also yields a calibration when a sextupole magnet is used, for example, when an insitu calibration [1] is required. The proposed calibration method has...
TC4 Symposium 2014
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Pasquale Arpaia, Marco Buzio, Ernesto De Matteis, Olaf Dunkel, Stephan Russenschuck
Recent compact accelerator developments for biomedical care and physics research has brought the need for small-aperture magnets as well as strongly bent magnet with curvature radii of less than 5 meters. Traditional transducers for magnetic measurements are not mechanically adaptable for local magnetic field measurements. In this paper, a new rotating coil transducer with compact design is proposed for local, transversal multipole scanning in straight and curved magnets. The requirements, design, prototyping, and the results of magnetic and electrical compatibility tests are presented.
TC4 Symposium 2014
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Pasquale Arpaia, Marco Buzio, Mario Kazazi, Stephan Russenschuck
A fluxmeter has been designed for measuring the magnetic field of axisymmetric magnets by exploiting the inherent symmetry. The fluxmeter yields a measurement of the magnetic flux linked with a pair of searching coils as a function of longitudinal position. The induction sensor is designed to be sensitive to the axial and radial components of the magnetic field. The sensor is mounted on a transport system that moves along the axis of the magnet. By integrating the induced voltage, the method eliminates the influence of the linear speed variations, thus relaxing requirements for uniform...
TC4 Symposium 2014
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K. Buhagiar, Philippe Lerch, A. Gabard, Marco Buzio, Stephane Sanfilippo, A. Foussat
A tokamak includes large scale magnets like poloidal and toroidal field coils. Shape deformations and/or assembly errors will lead to error fields in the final configuration, which is obtained by arranging several coils of both types. In the framework of the ITER tokamak project, we are developing a magnetic measurement system capable to record, at room temperature, the current center line (CCL) of the winding pack of the toroidal superconducting field coils. The knowledge of the CCL will be compared with survey data collected during manufacturing and assembly, and possibly be used as input...
TC4 Symposium 2014
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