The optimal design method for an open Magnetic Resonance Imaging （MRI） superconducting magnet with an active shielding configuration is proposed. Firstly, three pairs of current rings are employed as seed coils. By ...The optimal design method for an open Magnetic Resonance Imaging （MRI） superconducting magnet with an active shielding configuration is proposed. Firstly, three pairs of current rings are employed as seed coils. By optimizing the homogeneity of Diameter Sphere Voltnne （DSV）, the positions and currents of the seed coils will be obtained. Secondly, according to the positions and currents of the seed coils, the current density of superconducting wires is determined, and then the original sections for the coils can be achieved. An optimization for the homogeneity based on the constrained nonlincar optimization method is employed to determine the coils with good homogeneity. Thirdly, the magnetic field generated by previous coils is set as the background field, then add two coils with reverse current, and optimize the stray field line of 5 Gauss in a certain scope. Finally, a further optimization for the homogeneity is used to get Final coils. This method can also be used in the design of other axisynmaetfic superconducting MRI magnets.展开更多
The optimized design of magnetic field for a cold yoke superconducting solenoid is introduced in this paper. Using some kinds of optimization designs and OPERA,we optimize the main solenoid,cold yoke and compensated w...The optimized design of magnetic field for a cold yoke superconducting solenoid is introduced in this paper. Using some kinds of optimization designs and OPERA,we optimize the main solenoid,cold yoke and compensated winding.Through this design,the requests of the superconducting solenoid are realized.展开更多
基金supported by the National Natural Science Foundation of China(No.50577063)
文摘The optimal design method for an open Magnetic Resonance Imaging （MRI） superconducting magnet with an active shielding configuration is proposed. Firstly, three pairs of current rings are employed as seed coils. By optimizing the homogeneity of Diameter Sphere Voltnne （DSV）, the positions and currents of the seed coils will be obtained. Secondly, according to the positions and currents of the seed coils, the current density of superconducting wires is determined, and then the original sections for the coils can be achieved. An optimization for the homogeneity based on the constrained nonlincar optimization method is employed to determine the coils with good homogeneity. Thirdly, the magnetic field generated by previous coils is set as the background field, then add two coils with reverse current, and optimize the stray field line of 5 Gauss in a certain scope. Finally, a further optimization for the homogeneity is used to get Final coils. This method can also be used in the design of other axisynmaetfic superconducting MRI magnets.
文摘The optimized design of magnetic field for a cold yoke superconducting solenoid is introduced in this paper. Using some kinds of optimization designs and OPERA,we optimize the main solenoid,cold yoke and compensated winding.Through this design,the requests of the superconducting solenoid are realized.
