63 research outputs found
The ESSnuSB design study: overview and future prospects
ESSnuSB is a design study for an experiment to measure the CP violation in
the leptonic sector at the second neutrino oscillation maximum using a neutrino
beam driven by the uniquely powerful ESS linear accelerator. The reduced impact
of systematic errors on sensitivity at the second maximum allows for a very
precise measurement of the CP violating parameter. This review describes the
fundamental advantages of measurement at the 2nd maximum, the necessary
upgrades to the ESS linac in order to produce a neutrino beam, the near and far
detector complexes, the expected physics reach of the proposed ESSnuSB
experiment, concluding with the near future developments aimed at the project
realization.Comment: 19 pages, 11 figures; Corrected minor error in alphabetical ordering
of the authors: the author list is now fully alphabetical w.r.t. author
surnames as was intended. Corrected an incorrect affiliation for two authors
per their reques
Wavelets and Hilbert Transform for detection of short disturbances in electrical power networks
In electrical energy power network, disturbances can cause problems in electronic devices therefore their monitoring is fundamental to properly design the protection and compensation devices. In this paper we address the problem of disturbancesâ detection by using two different signal processing methods: Wavelets and Hilbert Transform (HT). Methods were tested under different conditions of noise and harmonic distortion (THD) showing the Hilbert Transform can be used as a valid approach for this type of phenomena
Sistema neurale per la previsione del carico elettrico di stazioni di telecomunicazione
Si descrive un sistema interconnesso di reti neuronali pr la previsione del carico di stazioni per telecomunicazion
Non recursive Nonlinear Least Squares for periodic signal fitting
A non-recursive version of Nonlinear Least Squares Fitting for frequency estimation is presented. This problem yields a closed-form solution exploiting a Taylor's series expansion. Respecting some conditions, the computational complexity is reduced, but equally the method assures that the accuracy reaches the Cramer-Rao Bound. The proposed method requires a frequency pre-estimate. A series of simulations has been made to determine how accurate the pre-estimate should be in order to ensure the achievement of the Cramer-Rao Bound in various conditions for different periodic signals. The execution time of the proposed algorithm is smaller compared to a single iteration cycle of the standard approach. The proposed method is useful in applications that require a high accuracy fitting of periodic signals, especially when limited computational resources are available or a real-time evaluation is needed
Non recursive multi-harmonic least squares fitting for grid frequency estimation
A new method to approximate the least squares multi-harmonic fitting is proposed. The basic idea is to expand in Taylorâs series the derivative on Ï of the least squares cost function around a central value, so reducing the frequency estimation to a calculation of a root of a polynomial. In this way the method provides a frequency estimation in a closed form avoiding the recursion that is necessary in the classical approach. The results show that the proposed algorithm reaches the CramerâRao bound in a narrow range of frequency around a pre-estimation. Increasing the approximation orders of the Taylorâs expansion the range of maximum accuracy widens. This method is particularly suitable in grid frequency estimation due its low variability. The proposed algorithm, preserving the accuracy, requires an execution time up to 8 times lower compared to a single iteration of the classical recursive approach
Methods for detection of sub-harmonics in power systems
With a wide range of power electronics-related applications
in power systems, harmonic currents are increasing at
an alarming rate which has greatly deteriorated the power
quality in electrical power networks. Moreover, some of
electronic controlled equipments used in power systems,
such as cycloconverters, produce sub-harmonics, a type of
waveform distortion, which can severely degrade the power
system performance. Therefore, they must be closely monitored.
Moreover, Fast Fourier Transform cannot accurately
analyze waveforms containing sub-harmonics because the
synchronization of the sampling procedure to subharmonics
is practically infeasible. The detection of subharmonics
requires a different approach from that used for
harmonics analysis. In most analysis methods the voltage
waveform is expected to be a pure sinusoid with a given
frequency and amplitude. Standard tools of harmonic
analysis based on the Fourier transform assume that only
harmonics are present in the investigated signal and the
periodicity intervals are fixed, while periodicity intervals in
the presence of interharmonics and sub-harmonics can be
variable and very long. Two novel approaches to analyze
non-stationary signals are shown in this paper. The first is
the âRoot-Musicâ harmonic retrieval method that is an
example of high-resolution eigenstructure-based method,
the second is a numerical method based on moving average
Scheda di acquisizione multi piattaforma per misurazioni certificate di power quality
Nell'ambito della conservazione dei beni culturali l'accumulo di polveri costituisce un grave problema. Le sue interazioni con i manufatti sono molteplici e i danni che essa puĂČ provocare sono notevoli
DETECTION OF SHORT TRANSIENTS AND INTERRUPTIONS USING THE HILBERT TRANSFORM
Abstract â In electrical energy power networks, disturbances can cause problems in electronic devices so their monitoring is fundamental in Power Quality. In this paper we address the problem of disturbances estimation by using the Hilbert Transform (HT). It is employed as an effective technique for tracking the voltage waveforms in electrical distribution systems. The mathematical simplicity of the proposed technique, compared with the commonly used algorithms from the literature, renders them competitive candidate for the on-line tracking of disturbances. The accurate tracking of the HT facilitates its implementation for the control of disturbances mitigation devices. Simulation results are provided to verify the tracking capabilities of the algorithm and this has been tested under different conditions: voltage dip with phase jump, noise and frequency changes shows that the Hilbert Transform can be used as a valid methodology for this type of phenomena
Power Quality As An Opportunity to Implement the Productivity and to Reduce the Costs
The article describes the hardware and software of the instrument placed in some European countries able to collect Power Quality (PQ) data. These instruments are provided by one of the bigger UPS farmer in the world. The collected data have been analyzed by Roma Tre University that has elaborated some statistical evaluation of the European PQ. Some economical evaluation on the industrial productivity, connected with the lack of PQ, are also presented. It is also shown a possible creation, in the future, of new corporations able to face PQ problems with the aim to provide new kind of service for those customers particularly sensible to PQ
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