An Energy-Efficient Pulsed Magnet for Magnetic Resonance Imaging

Electromagnets in low-field portable MRI systems offer significant advantages, providing adjustable field strength and enhanced portability. Nonetheless, research on main-field amplifiers for these systems remains limited. This digest presents a pulsed-magnet architecture tailored to low-field portable MRI. The design integrates a 1MHz, 100V GaN buck converter with a 1200V SiC full bridge to drive a Helmholtz coil via shaped current pulses, enabling high-bandwidth field modulation and energy recycling. A proof-of-concept prototype demonstrates B<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</inf> =27.44mT with µs-level rise/fall times and stable operation under multi-second pulse sequences.