Nested coil assembly for generating a constrained magnetic field
View Patent ↗The present invention relates to a magnetic field configuration referred to as a Nested Dipole Gap Magnetic Field. The Nested Dipole Gap Magnetic Field is generated within a working gap region formed between two electromagnetic coil structures arranged to produce a coupled magnetic topology. Within the gap, a primary or main dipole magnetic field is established along a central region, while a secondary return magnetic field of opposite directional polarity is formed at larger radial distances surrounding the primary field. The secondary field encloses, confines, and stabilizes the primary magnetic field, resulting in a nested magnetic field distribution that creates a controlled spatial field boundary. This configuration enables magnetic field shaping, confinement, and isolation within a well-defined gap region, and is applicable to systems requiring controlled charged particle behavior, plasma confinement, ion acceleration regions, and electromagnetic reaction chambers.
1 . An apparatus for generating a magnetic field for use in vacuum electromagnetic operations involving charged particles or plasma, comprising:
a first nested coil assembly comprising an inner coil and an outer coil, the outer coil being disposed radially external and generally concentric to the inner coil, wherein the inner coil is configured to carry a primary current generating a primary magnetic field, and the outer coil is configured to carry an independent secondary current of opposite polarity generating a return magnetic field radially enclosing the primary magnetic field;
a second nested coil assembly, coaxially aligned with the first nested coil assembly and comprising of an inner coil and an outer coil, wherein the inner coil is configured to carry a primary current generating a primary magnetic field, and the outer coil is configured to carry an independent secondary current of opposite polarity generating a return magnetic field radially enclosing the primary magnetic field;
a support structure mechanically coupled to the first nested coil assembly and the second nested coil assembly to maintain a predetermined spatial relationship along the common axis between the coil assemblies, defining a working gap region therebetween, wherein the support structure is external to the working gap region; and
wherein the first nested coil assembly and the second nested coil assembly are axially separated from one another to define a working gap region therebetween, the working gap region being maintained as a vacuum space free of ferromagnetic material and configured to receive a gas or plasma therein, such that within the working gap region, the primary magnetic field is confined and enclosed radially by the opposing secondary magnetic field, establishing a nested magnetic field configuration for confinement and control of charged particles or plasma within the working gap region.
2 . The apparatus of claim 1 , wherein the magnetic field distribution within the working gap region is defined by the current and voltage configured for the first and second nested coil assemblies.
3 . The apparatus of claim 1 , wherein the magnetic field distribution within the working gap region is defined by the number of windings present in the first and second nested coil assemblies as well as the ratio of windings between the inner and outer coils.
4 . The apparatus of claim 1 , wherein a wire gauge or a cross-sectional geometry is selected to configure a specific magnetic field distribution within the working gap region.
5 . The apparatus of claim 1 , wherein the magnetic field distribution within the working gap region is defined by the axial distance between the first and secondary nested coil assemblies, the radial distance between the first inner coil and the first outer coil, the radial distance between the second inner coil and the second outer coil, or a combination thereof.
6 . The apparatus of claim 1 , further comprising a plurality of nested coil sets disposed along the common the plurality of nested coils designed to produce a sequence of alternating magnetic field polarities progressing radially outward from the center.
7 . The apparatus of claim 6 , wherein a plurality of high-permeability cores are selected to determine the desired magnetic field distribution within the working gap region.
8 . The apparatus of claim 1 , wherein the working gap region is maintained at a partial vacuum and charged with a controlled gas composition such that a plasma is generated and confined by the nested magnetic field configuration within the working gap region.
9 . The apparatus of claim 1 , wherein the primary and return magnetic fields are produced using resistive electromagnets, superconducting magnets, or permanent magnets, with or without magnetic-core materials.
10 . The apparatus of claim 1 , wherein the supporting structure is constructed so as not to interfere with the vacuum space of the working gap region, and is positioned entirely external to the working gap region.
11 . A Nested Coil Assembly for generating a constrained magnetic field for confinement and control of charged particles or plasma in a vacuum environment, comprising:
a pair of high-permeability cores aligned along a common axis;
a primary inner coil positioned inside each core, configured to carry a primary current that generates a primary magnetic field directed along the common axis;
a secondary outer coil wrapped around each core and axially separated from the primary inner coil, configured to carry a secondary current of opposite polarity relative to the primary current to generate a secondary magnetic field surrounding the primary magnetic field;
a support structure maintaining the axial separation between the primary and secondary coil sets to define a working gap region between them, the working gap region being a vacuum space free of ferromagnetic material and configured for charged particle or plasma operations; and
wherein the pair of high-permeability cores provide a low-reluctance flux path that confines and intensifies the primary magnetic field within the working gap region, and the secondary magnetic field counterbalances the primary magnetic field external to the working gap region, thereby establishing a nested dipole magnetic field configuration within the vacuum space for confinement of charged particles or plasma.
12 . A method for generating alternate polarity nested magnetic fields for confinement and control of charged particles or plasma using two axially separated coil sets, the method comprising the steps of:
providing a nested coil assembly comprising, an inner coil set and an outer coil set wound and the two sets separated as to define a working gap region, the working gap region being a vacuum space free of ferromagnetic material;
applying a primary current to the primary coil set;
applying a secondary current of opposite polarity to the secondary coil set to generate an opposing secondary magnetic field; and
constraining the primary magnetic field by using the opposing secondary magnetic field to counterbalance the primary magnetic field external to the working gap region, thereby concentrating and stabilizing the primary magnetic field within the defined working gap region to confine and control charged particles or plasma therein.