Yihe Hua1, Longzhi Jiang2, Graeme C. Mckinnon3, Seung-Kyun Lee4, Anbo Wu1
1GE Global Research, Shanghai, China; 2GE Healthcare, Florence, SC, United States; 3GE Healthcare, Waukesha, WI; 4GE Global Research, Niskayuna, NY, United States
In conductive cooling magnet, joule heating in 4K region is critical due to the cold head capability limitation. When a MRI scanner is operating, the current in gradient coil will induce EC in magnet metal structure, which will vibrate by the Lorentz force due to the main field. The motion will further generate motional EC. In this article Joule heating in cryostat, AC loss in superconductive wires and dielectric loss in coil epoxy are calculated for one 1.5T MRI magnet including full metal VV, TS and coil former with 2D harmonic analysis. The z-gradient coil is optimized towards heating minimization.