M. S. de Castro, R. C. S Freire, E. G da Costa, J. R. Lima F., L. F. D. da Silva
Grounding grids are fundamental for the safety of people and equipments in power system. Atmospheric discharges cause serious damage to the electrical system. So, it is important to study the performance of grounding grids subjected to high intensity current impulses. In order to analyze the performance of grounding grid subjected to current impulses, it was applied current impulses up to 2 kA into the soil. To produce the current impulses, it was used from 15 kV to 35 kV to charge the capacitors of an impulse generator. By using an oscilloscope it was acquired current and voltage signals...
XXI IMEKO World Congress
· TC4
· 2015
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Giovanni Betta, Domenico Capriglione, Gianni Cerro, Luigi Ferrigno, Gianfranco Miele
The smoothing process is a fundamental task in many application fields. This paper proposes a novel method to smooth raw data, based on the concept of polynomial fitting. It is thought to be effective in Cognitive Radio applications, especially focused on spectrum sensing tasks. The method is intended to be used instead of today’s traditional smoothing filters, because of some advantages in terms of shaping retainment, data shifting problem avoidance, acceptable computational intensity, appreciable noise reduction property. The goodness of the proposal has been proved considering the H 1...
XXI IMEKO World Congress
· TC4
· 2015
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Pasquale Arpaia, Domenico Caiazza, Carlo Petrone, Stephan Russenschuck
A single conducting wire is used for localizing the magnetic axis of a quadrupole magnet. The localization is performed by both the stretched-wire and the vibrating-wire method. The compatibility of the two measurements is demonstrated and the measurement repeatability is assessed for both the methods at varying the magnet gradient. Furthermore, the influence of the background magnetic field in the two approaches is studied at varying the magnetic field strength. Experimental results are given for a normal-conducting quadrupole magnet.
XXI IMEKO World Congress
· TC4
· 2015
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Thiago Brito Pereira de Souza, Marcelo Melo da Costa, André Ferraioli Neto
The measurement of electrical energy is very important for Eletrobras Eletronorte, as this is their main product offered to its customers. This paper aims to implement improvements in the calibration process of this electricity meters used in measuring systems. These improvements presented achieve greater reliability in the calibration process, greater availability of measurement standards in the laboratory and the reduction of meter calibration time. This paper presents strategies to improve the calibration process of these meters, with results that characterize the effectiveness of the...
XXI IMEKO World Congress
· TC4
· 2015
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Vitalia E. Baranova, Pavel F. Baranov, Sergey V. Muravyov, Sergey V. Uchaykin
The paper describes an experience in developing one-component magnetometer based on a miniature planar fluxgate sensor for measuring ultra low magnetic induction and operating at extremely low temperatures. A fluxgate magnetic sensor was fabricated in PCB technology with geometric dimensions 10 × 6 × 2 mm³. The linearity error of the developed magnetometer is about 1.9 % of full scale and its maximum sensitivity is about 99 V/mT.
XXI IMEKO World Congress
· TC4
· 2015
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Pavel F. Baranov, Edvard I. Tsimbalist, Valeriy N. Borikov, Diana G. Soltanova
Current shunts are widely used in metrological practice. The shunt is required to determine the value of its resistance on DC and AC currents to determine the transfer ratio error in the wide frequency band in process calibration. The paper describes a procedure for measuring the complex impedance of transfer ratio of current shunts in the frequency band using the lock-in amplifier with the differential input. The experimental results of the proposed procedure are described.
XXI IMEKO World Congress
· TC4
· 2015
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Sioma Baltianski
A new and efficient technique of impedance spectra interpretation is presented. The decomposition of the full impedance into separate parts is accomplished by fitting data using a parametric distribution function of relaxation times in a convoluted form. Each particular impedance element is presented as the asymptotic model in the next step. The result of this procedure is unambiguous. This is demonstrated using electroceramic samples in the ranges T = 200 - 475 °C and f = 10 mHz - 30 MHz.
XXI IMEKO World Congress
· TC4
· 2015
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Pasquale Arpaia, Carlo Baccigalupi, Miguel Cerqueira Bastos, Michele Martino
The proof of principle of a real-time data acquisition system to be integrated into a digital control loop for controlling the power converters of the Compact LInear Collider is presented. The system is based on an ultra low noise analogue front-end with 1.1 ppm RMS noise (referred to input), and about 1 µs of real-time delay. After the analogue conditioning, a fully-differential analogue-to-digital converter is foreseen. The requirements of this system, directly derived from the accelerator performance, are discussed and translated into design specification. The results obtained by means of...
XXI IMEKO World Congress
· TC4
· 2015
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Dušan Agrež, Damir Ilić, Janko Drnovšek
In paper, a frequency domain algorithm for estimation of the sine signal parameters in the case of signal sampling by averaging in the aperture time is presented. Prior to estimations in the frequency domain the sampled signal is padded with the signal average values in the aperture times and zeroes outside. We can increase padding points and with this nearing the errors to the level as with estimations of the signal without average sampling.
XXI IMEKO World Congress
· TC4
· 2015
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Dušan Agrež
In paper, a frequency domain estimation algorithm for fast measurement of the signal frequency in the measurement time below one period is presented. When the time is shortened below the signal period, the DC coefficient of the discrete Fourier transformation is taken into account. An analysis is made to study the influence of the leakage effect, offset in the measurement channel, and noise when the Rife-Vincent windows class I (the rectangular window, the Hann window, and others with higher order) are used. Simulations changing the bias of the amplitude DC coefficients support the analysis.
XXI IMEKO World Congress
· TC4
· 2015
· Download