Search results for "Epstein frame"
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Characterisation of electric alloys for electric drives
1996
Knowledge of the magnetic and loss charactenstics of electric alloys is necessary for the computation and design of electrical machines. Over a long period of time, and more recently, many devices have been proposed for this characterisation. They test ferromagnetic sheets under conditions of unidirectional magnetic flux density. Other methods are derived from some of these devices, but they use conditions of rotating flux density. In the paper the authors show with the use of numerical computation that, in all these testing systems, the distribution of the magnetic flux density through the thickness of the sheet is uniform and does not take into account the edge effect which exists in rota…
Characterisation of nonoriented electric alloys under nonconventional conditions
1996
The variations of magnetic and loss characteristics of nonoriented cobalt-iron and silicon-iron sheets have been investigated using an Epstein frame. Cobalt-iron alloys have been tested under sinusoidal magnetic flux density with respect to frequency and temperature. Both kinds of alloys have also been investigated with respect to frequency, time constant wavefront and temperature under trapezoidal flux density. The qualitative behaviour is identical under both flux density conditions for all these alloys. These investigations have made it possible to model the variations of iron losses with experimental parameters, except the temperature. These quantitative evolutions differ with alloy and…