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Generalized magnetostatic target field method for shielded magnetic field coils in a separable coordinate system
Seung-Kyun Lee1, John Schenck1
1GE Global Research, Niskayuna, New York 12309, USA.
Journal of Applied Physics
|May 8, 2023
Summary
This study introduces a theoretical method to calculate surface current densities for generating specific static magnetic fields. The approach simplifies magnetostatic problems into scalar field problems for designing gradient field coils.
Area of Science:
- Electromagnetism
- Applied Physics
- Coil Design
Background:
- Designing coils for specific magnetic field profiles is crucial in many scientific applications.
- Traditional methods often treat magnetostatic problems as complex vector field calculations.
- Existing techniques may lack analytical solutions for generating targeted magnetic fields in specific regions.
Purpose of the Study:
- To develop a theoretical method for analytically calculating surface current densities.
- To generate a desired static magnetic field in one region while ensuring zero field in another.
- To simplify the magnetostatic problem by reformulating it as a scalar field problem.
Main Methods:
- Utilized the relationship between surface current density and stream function.
- Equated stream functions with surface magnetic dipole density.
- Formulated the magnetostatic problem as a scalar field problem using the magnetic scalar potential and Green's function.
Main Results:
- Established a method to analytically calculate surface current densities for desired magnetic fields.
- Demonstrated a simplified scalar field approach to magnetostatics.
- Showcased a relationship between harmonic components of stream and magnetic scalar potentials in separable coordinate systems.
Conclusions:
- The developed theoretical method provides an analytical solution for designing surface current densities.
- This approach simplifies complex magnetostatic problems into manageable scalar field calculations.
- The method is applicable to designing actively shielded, linear gradient field coils in various coordinate systems.
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