Results 211 to 220 of about 9,938 (266)

Intercomparison on PD calibrators and PD instruments

11th International Symposium on High-Voltage Engineering (ISH 99), 1999
Within the framework of a European project, two partial discharge calibrators were circulated to thirteen laboratories for an intercomparison of impulse charge measurements in the range between 1 pC and 500 pC. The deviations of the charge values q reported by the laboratories were, with a very few exceptions, within ±(0,1 pC + 0,03-q).
SCHON K, LEMKE E, BERGMAN A, GARNACHO F, MUHR M, RIZZI G, SARDI, ANGELO, LUCAS W, ELZE H, GUNNARSSON O, SIMON P, PACK S, GIORGI P. A, PESAVENTO G, GOBBO R, GOMEZ F. N, DOMINGUES F, BLANC I, HALLSTROM J, ZAENGL W, CLAUDI A, PIIROINEN J, WEBER H. J, BROOKS R.   +23 more
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New approach to calibration in PD measurements

IMTC/99. Proceedings of the 16th IEEE Instrumentation and Measurement Technology Conference (Cat. No.99CH36309), 2003
Two different PD measurement instruments could detect different PD values on the same test object even if the measurement conditions are identical. This result is due to the quasi integration error presents in classical PD measurement systems. In this paper the quasi integration error is investigated and two parameters are proposed to qualify the PD ...
E. Carminati, M. Lazzaroni
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PD apparent charge estimation and calibration: A critical review

IEEE Transactions on Dielectrics and Electrical Insulation, 2010
This paper focuses on the limits of partial discharge apparent charge estimation and calibration using an unified approach. The fundamental problems that prevent accurate apparent charge estimates (resonances, attenuation and partial discharge pulse splitting) are tackled through this approach, highlighting the physical limitations that prevent partial
CAVALLINI, ANDREA, MONTANARI, GIAN CARLO, TOZZI, MARCO   +2 more
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A standard calibrator for PD testing

Conference Record of the 1992 IEEE International Symposium on Electrical Insulation, 2003
In the classical partial discharge (PD) measuring circuit the current represents the signal that allows the detection of PDs in the tested sample. This current is converted into a voltage by the measuring impedance, amplified, and filtered. The integration process is essential.
E. Carminati, A. Gandelli, P. Osvath
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Development and application of a programmable PD calibrator

2008 Conference on Precision Electromagnetic Measurements Digest, 2008
A programmable partial discharge calibrator is described, which is constituted by an arbitrary waveform generator series connected to a capacitor. The step voltage waveform supplied by the generator is software controlled. The characteristics and the capabilities of the calibrator are presented and the procedures adopted for its characterization are ...
M. Chiampi, G. Crotti, Y. Hu, A. Sardi
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Investigation of Pd–C cells to improve thermocouple calibration

Metrologia, 2011
An intercomparison of the melting temperatures of four Pd–C eutectic fixed-point cells was performed using four Pt/Pd thermocouples. The cells are designed for the calibration of thermocouples and were constructed in the participating laboratories of NPL, LNE, NMIJ and PTB. The measurements were performed in four different high-temperature furnaces but
J V Pearce, F Edler, C J Elliott, G Failleau, R Morice, H Ogura   +5 more
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Computation of PD calibration reflectograms in shielded power cable

IEEE Transactions on Dielectrics and Electrical Insulation, 2008
The basis for computing PD calibration reflectograms in shielded power cable is presented. The computed reflectograms include the effects of cable attenuation, initial pulse width, cable length, and PD detection bandwidth. The authors have developed a program based on the algorithms presented in this paper which they are making freely available to the ...
Naima Oussalah, Steven Boggs
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Calibration of Pd-porphyrin phosphorescence for oxygen concentration measurements in vivo

Journal of Applied Physiology, 1996
Sinaasappel, M., and C. Ince. Calibration of Pd-porphyrin phosphorescence for oxygen concentration measurements in vivo. J. Appl. Physiol. 81(5): 2297–2303, 1996.—Quantitative measurement of oxygen concentrations in the microvasculature is of prime importance in issues related to oxygen transport to tissue.
Sinaasappel, M., Ince, C.
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Preparation and calibration of ultrathin Zn layers on Pd(111)

Applied Surface Science, 2009
Abstract The general assumption that metal vapors stick at any surface with probability one at room temperature is a necessary requirement for the correct metal deposition rate determination by quartz microbalance measurements. In a combined thermal desorption spectroscopy (TDS) and Auger electron spectroscopy (AES) study on clean and sulphur covered
M. Kratzer, A. Tamtögl, J. Killmann, R. Schennach, A. Winkler   +4 more
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Possibility of PD calibration on power transformers using UHF probes

IEEE Transactions on Dielectrics and Electrical Insulation, 2017
Partial Discharge (PD) measurement on power transformers using Ultra-High Frequency (UHF) techniques has great advantages on IEC method including possibility of online application, localization and greater immunity against external noises. But lacking a method to calibrate or at least determine sensitivity of UHF method for power transformers is the ...
H. Jahangir, A. Akbari, P. Werle, J. Szczechowski   +3 more
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