Design and construction of new small gradient coils for animal MRI

We represent the design and construction of Y and Z gradient coils targeted to work with a small cylindrical NMR magnet. The coils geometries are optimized based on the predetermined gradient strength and slew rate values by considering the lower power consumption using the particle swarm optimization (PSO) algorithm in Computer Simulation Technology (CST) environment. Simulation results verify that magnitudes of field strength and the slew rate have reached up to 109 mT/m and 1264 mT/m.ms for the Y-gradient coil and increased to 144 mT/m and 1297 mT/m.ms for the Z-gradient coil respectively. Furthermore, the optimal geometry of the Z-gradient coil resulted in the simulation study was then fabricated and its parameters were measured using a Hall sensor for validating the simulation results. Gradient strength and slew rate of the fabricated Z gradient coil were measured 131 mT/m and 1180 mT/m.ms respectively which has only a 9% difference with the corresponding simulated parameters.

Keywords:

Gradient Coil , Slew Rate , Field Gradient Strength , CST.