A GTO speed-up inverter for fast-scan magnetic resonance imaging

Magnetic resonance imaging (MRI) machines require unique high-power electronic systems for the generation of pulsed B gradient fields, especially for echo planar MRI, where images are taken in 25-30 ms instead of minutes. The speedup inverter described has been implemented with gate turn-off thyristors (GTOs). A novel nonresonant circuit combines the advantages of high-efficiency switch-mode power conversion techniques for the generation of megawatt pulses. An order-of-magnitude increase in available gradient power has been achieved with excellent fidelity and stability. >