1,721,154 research outputs found
Set up and characterization of a measuring system for PQ measurements in a MV site with PV generation
Full text linkEvaluation of Frequency Behavior of Coils for Reference Magnetic Field Generation
No full text—The frequency behavior of coils for the generation of
reference time-varying magnetic fields is evaluated starting from
the coil construction parameters (geometrical dimensions, number
of turns). A coil equivalent circuit with lumped parameters is con-
sidered and the related equation system is solved in the frequency
domain. The computed frequency behavior of the coil impedance
is validated by comparison with experimental data. The operating
frequency limit is identified fromthe analysis of the coil impedance
variation with frequency as a function of the construction param-
eters
Experimental evaluation of earth currents generated by a DC traction network
No full textEarth currents generated by a DC traction
network, causing interference with the functioning of
sensitive apparatuses and plants located in the
surrounding area, are experimentally investigated.
Measurements of the potential variation of a lighting
plant earthing network are made at the same time with
significant railway load variations. The presence and
the amount of earth current with respect to that flowing
in the overhead line are experimentally evaluated
through measurements of voltage drops across rail
sections, when a defined current is imposed on the
supply line for a short time
Analysis of electric contact behaviour under different operating conditions by a finite difference model
No full text
Problems in the detection of Quasi-Rectangular magnetic flux density waveforms
No full textThe paper focuses on the distortions introduced
by low frequency magnetic field meters in the measurement
of pulsed or periodic quasi-rectangular waveforms, such as
those experienced near welding devices or Magnetic
Resonance Imaging (MRI) machines. Starting from the
meter frequency response, evaluated by generating reference
sinusoidal magnetic fields up to a hundred of hertz, a
circuital model is worked out, which reproduces the
distortions of the measured signal due to the meter input
high pass filter. By making use of the modelled filter, a time
domain reconstruction procedure is implemented that allows
the reproduction of the actual magnetic field shape starting
from the measured behaviour
Analisi di situazioni critiche nella valutazione dell’esposizione a campi magnetici con forme d’onda complesse
No full text
- …
