Multi-tunnel electric machine
Disclosed are various embodiments for an electric machine where the stator is a coil assembly and the rotor is a magnetic toroidal cylindrical tunnel or where the rotor is a coil assembly and the stator is a magnetic toroidal cylindrical tunnel.
1. A rotary electric machine comprising:
a magnetic toroidal cylinder radially arranged about an axial axis to form a circular path, the magnetic toroidal cylinder comprising:
a first plurality of magnetic tunnel segments, wherein each magnetic tunnel segment of the first plurality of magnetic tunnel segments comprises:
a first magnetic outer wall;
a first magnetic inner wall;
a first side magnetic wall;
a first side opposing magnetic wall;
wherein each magnetic tunnel segment of the first plurality of magnetic tunnel segment has an NNNN magnetic polarity configuration;
a second plurality of magnetic tunnel segments, wherein each magnetic tunnel segment of the second plurality of magnetic tunnel segments is interspersed between individual tunnel segments of the first plurality of tunnel segments and each magnetic tunnel segment of the second plurality of tunnel segments comprises:
a second magnetic outer wall;
a second magnetic inner wall;
a second side magnetic wall;
a second side opposing magnetic wall;
wherein each magnetic tunnel segment of the second plurality of magnetic tunnel segment has a SSSS magnetic polarity configuration;
a coil assembly positioned within the magnetic toroidal cylinder, the coil assembly comprising:
a circular yoke;
a plurality of coil modules radially positioned about the axial axis and wherein a portion of the circular yoke goes through an aperture defined in each coil module, wherein each coil module comprises;
at least one coil winding, a PCB module positioned radially adjacent to an inside face of the at least one coil winding and is electrically coupled to the at least one coil winding and having a PCB connector for electrically connecting the at least one coil winding to a controller or a PCB power module,
at least one stator pole positioned on the circular yoke adjacent to the at least one coil winding wherein the at least one stator pole consists of a vertical element, an outer face, an inner face, a side face, and an opposing side face wherein the faces are wider than the vertical element to define recesses on each side of the at least one stator pole sized to partially enclose adjacent coil windings and the PCB module,
an alignment feature formed on an interior side of each coil module; and
at least one alignment ring having a plurality of alignment spokes sized and shaped to couple to the alignment feature of each coil module.
2. The rotary electric machine of claim 1 , further comprising a controller in electronic communication with the plurality of coil modules, the controller positioned within a space created by a plurality of first magnetic inner walls from the first plurality of magnetic tunnel segments and by a plurality of second magnetic inner walls from the second plurality of magnetic tunnel segments.
3. The rotary electric machine of claim 1 , wherein the coil module further comprises a bobbin having an aperture sized to fit over the circular yoke, and the at least one coil winding is wound around the bobbin.
4. The rotary electric machine of claim 3 , wherein the coil module further comprises a second stator pole positioned on an opposing side of the at least one coil winding from the at least one stator pole, wherein the at least one stator pole and the second stator pole function together to operate as single stator pole for phasing purposes.
5. The rotary electric machine of claim 3 , wherein the recesses of the at least one stator pole on each side of the at least one stator pole is sized to also partially enclose the bobbin surrounded by an adjacent coil winding.
6. The rotary electric machine of claim 3 , wherein the coil module further comprises a spacer positioned adjacent to the at least one stator pole for electrically isolating the at least one stator pole and for conducting heat away from the at least one coil winding and the at least one stator pole.
7. The rotary electric machine of claim 1 , wherein the circular yoke comprises a first semi-circular portion and a second semi-circular portion.
8. The rotary electric machine of claim 1 , wherein the circular yoke is formed from laminated electrical steel tape comprising planes of laminations generally parallel to a direction of the axial axis.
9. The rotary electric machine of claim 1 , wherein the circular yoke is formed from ferromagnetic open cell foam material which is infused with a dissimilar ferrous metal matrix.
10. The rotary electric machine of claim 1 , wherein the circular yoke is formed from ferromagnetic open cell foam material which is infused with a non-ferrous metal matrix.
11. The rotary electric machine of claim 1 , where the at least one stator pole is made from a laminated material having planes of laminations which are generally radial to the axial axis.
12. The rotary electric machine of claim 1 , where the at least one stator pole is made from a laminated material having planes of laminations which are generally radial to the axial axis and the at least one stator pole also defines a flux-shaping cavity configured to optimize a flux density distribution within the at least one stator pole and the circular yoke.
13. A method of manufacturing a coil assembly, the method comprising:
providing a bobbin with a first central aperture;
winding a wire around the bobbin to form a coil winding,
coupling a PCB module to an inside face of the coil winding and electrically coupling the coil winding to the PCB module;
positioning the bobbin, the coil winding, and PCB module within a recess of a pole portion to form a coil module, wherein the pole portion also defines a second central aperture;
repeating the providing, the winding, the coupling, and the positioning steps above to form a plurality of coil modules;
sliding a single coil module of the plurality of coil modules over a first semicircular yoke segment;
sliding additional coil modules over the first semi-circular yoke segment until a predetermined number of coil modules has been positioned onto the first semi-circular yoke segment;
sliding another single coil module of the plurality of coil modules over a second semi-circular yoke segment;
sliding additional coil modules over the second semi-circular yoke segment until a second predetermined number of coil modules has been positioned onto the second semi-circular yoke segment; and
joining the first semi-circular yoke segment to the second semi-circular yoke segment to form a complete coil assembly.
14. The method of claim 13 , further comprising coupling a spacer to the pole portion when forming the coil module.
15. The method of claim 13 , further comprising coupling an alignment ring to alignment notches on each of the plurality of coil modules to the pole portion when forming the coil module.