Globally Optimal Algorithm for Design of 0.7 T Actively Shielded Whole-Body Open MRI Superconducting Magnet System

A 0.7-T open magnetic resonance imaging superconducting magnet system with actively shielded technique was designed and will be fabricated. The design methodology of the open structure magnetic resonance superconducting magnet is employed by a hybrid optimization strategy with combination with linear programming and nonlinear optimization algorithm. The linear programming was employed to search the coils´ initial position and shape with advantage of high efficient and global optimization, and the nonlinear optimization algorithm was to discrete the initial data into solenoids to reach the system requirements, such as field strength and homogeneity over an interesting region, the scope of 5 Gauss fringe field, maximum magnetic field and maximum hoop stress within solenoids. The hybrid optimization is flexible and efficient to design conventional cylindrical system and split open system.