International Journal on Magnetic Particle Imaging
Vol 8 No 1 Suppl 1 (2022): Int J Mag Part Imag

Proceedings Articles

Shift coil assembly for a rotating permanent magnet FFL human-scale fMPI imager

Main Article Content

Alex Barksdale , Erica Mason , Eli Mattingly  , Monika Sliwiak  , John Drago  , Lawrence Wald  


We present the fabrication and characterization of a shift coil assembly designed for a rotating permanent magnet FFL human fMPI imager. The realized system consists of two sets of inner and outer coils (“racetracks”), each driven by an independent amplifier. Hollow conductors and a highly parallel water-cooling circuit provide heat removal during operation. The measured electrical characteristics of the coils (Rinner = 310 mOhms, Linner = 26 mH, Router = 399 mOhms, Louter =41 mH, M = 22.6 mH) match simulated values well, and field efficiency measurements demonstrate ability to shift a 1.03 T/m FFL over a 20 cm FOV within driving capabilities of the amplifier system (field efficiency = 0.215 mT/A).

Article Details


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