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The paper contains an analysis of the classical Preisach model from a frequency point of view. A Fourier analysis retrieves the necessary and sufficient conditions on the Preisach weighting function to have an output with half-wave symmetry, i.e. only odd ...
Estimates of transfer functions from measurements contain undesired information -- noise -- whose effect can partly be taken away by applying different smoothing techniques. One such smoothing technique suggests to remove the noise by gating the impulse re ...
An original electrical AC loss experimental set-up is presented. For loss comparison purpose, Ic and exponent n are measured with a DC magnetic field between 2 and 400 mT applied perpendicularly to the axis of the sample using a specially designed electrom ...
Transient stability investigations consist of studying the rotor oscillations of generators (electro-mechanic oscillations, 0.1-2 Hz) after the occurrence of a fault of large amplitude, e.g. short circuit. The goal is to indicate if the generators are capa ...
We present a parametrised Preisach-type model that describes the hysteresis exhibited by the high temperature superconductors (HTSC); hysteresis is the main cause for losses in the subcritical domain. The parametrised model, in combination with electrical ...
The paper contains an analysis of the classical Preisach Model from a symmetry and a frequency point of view. Increasing and decreasing inputs have no fundamental difference, which leads to a simplified implementation by changing indices. Symmetry implies ...
The classic Preisach model is used to describe a general hysteretic behaviour, and as most nonlinear systems, its output contains higher harmonics. A Fourier analysis of a specific class of weighting functions for the Preisach model relates some free param ...
We use a dual channel digital lock-in to perform electrical measurement of AC losses at power frequencies. A DC magnetic field between 2 and 400 mT is applied with a varying angle from parallel to perpendicular to the tape surface, thus having a complete v ...
An identification method for Preisach-type models of hysteresis is presented. By using a phenomenological Preisach-type model for hysteresis we can obtain an exact model for the magnetisation hysteresis in the cases of tapes with strip and with elliptical ...
