Open AccessFerrite core non‐linearity in coils for magnetic neurostimulation
Author(s) -
RamRakhyani Anil Kumar,
Lazzi Gianluca
Publication year - 2014
Publication title -
healthcare technology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.45
H-Index - 19
ISSN - 2053-3713
DOI - 10.1049/htl.2014.0087
Subject(s) - ferrite core , electromagnetic coil , materials science , inductance , voltage , neurostimulation , ferrite (magnet) , waveform , linearity , capacitive sensing , acoustics , nuclear magnetic resonance , electrical engineering , composite material , physics , engineering , stimulation , neuroscience , biology
The need to correctly predict the voltage across terminals of mm‐sized coils, with ferrite core, to be employed for magnetic stimulation of the peripheral neural system is the motivation for this work. In such applications, which rely on a capacitive discharge on the coil to realise a transient voltage curve of duration and strength suitable for neural stimulation, the correct modelling of the non‐linearity of the ferrite core is critical. A demonstration of how a finite‐difference model of the considered coils, which include a model of the current‐controlled inductance in the coil, can be used to correctly predict the time‐domain voltage waveforms across the terminals of a test coil is presented. Five coils of different dimensions, loaded with ferrite cores, have been fabricated and tested: the measured magnitude and width of the induced pulse are within 10% of simulated values.