A Design Method for Asymmetric Gradient Coils with Reduced Hot Spot Temperatures

Peter T. While¹, Larry K. Forbes¹, Stuart Crozier²

Gradient heating and coil hot spots can result in system failure or image distortion. A previously reported method is extended to the design of asymmetric gradient coils with improved temperature distributions and reduced hot spot temperatures. The method combines an optimisation constraint derived from a spatial temperature distribution model with a relaxed fixed point iteration routine. In comparison to minimum power coils, the new coil windings are more spread out with lower maximum temperatures, at little or no cost to coil performance. For the design of coils with different thermal material properties, considerably different winding pattern solutions are obtained.