Patent Publication Number: US-2023155441-A1

Title: System for an electric motor with coil assemblies and internal radial magnetic elements

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This Application is a continuation of U.S. Non-Provisional Application No. 17/831,337, filed on 02-JUNE-2022, which is incorporated in its entirety by this reference. 
     Application No. 17/831,337 also claims the benefit of U.S. Provisional Application No. 63/195,764, filed on 02-JUN-2021, which is incorporated in its entirety by this reference. 
     Application No. 17/831,337 also claims the benefit of U.S. Provisional Application No. 63/252,868, filed on 06-OCT-2021, which is incorporated in its entirety by this reference. 
    
    
     TECHNICAL FIELD 
     This invention relates generally to the field of electric motors and more specifically to a new and useful system for a rotor located internally within a set of coil assemblies in the field of electric motors. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG.  1    is a schematic representation of the system; 
         FIG.  2    is a schematic representation of the system; 
         FIG.  3    is a schematic representation of the system; 
         FIG.  4    is a schematic representation of the system; 
         FIG.  5    is a schematic representation of the system; 
         FIG.  6    is a schematic representation of the system; 
         FIG.  7    is a schematic representation of the system; 
         FIG.  8    is a schematic representation of one variation of the system; 
         FIG.  9    is another schematic representation of one variation of the system; and 
         FIG.  10    is another schematic representation of one variation of the system. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     The following description of embodiments of the invention is not intended to limit the invention to these embodiments but rather to enable a person skilled in the art to make and use this invention. Variations, configurations, implementations, example implementations, and examples described herein are optional and are not exclusive to the variations, configurations, implementations, example implementations, and examples they describe. The invention described herein can include any and all permutations of these variations, configurations, implementations, example implementations, and examples. 
     1. System 
     As shown in  FIG.  1   , a system  100  includes a rotor  110  including a set of magnetic elements  112  arranged radially about a motor axis within a body  115 . The body  115  of the rotor  110  defines an inner radial surface  116 , an outer radial surface  117 , a first axial face  118 , and a second axial face  119  opposite the first axial face  118 . The system  100  further includes a stator  130  including a set of coil assemblies  131  arranged in a radial pattern about the rotor  110 . Each coil assembly in the set of coil assemblies  131  includes an outer hook element  133  comprising a first set of leads  155  and an inner hook element  143  comprising a second set of leads  156 . The outer hook element  133  extends across the first axial face  118  and the outer radial surface  117  of the rotor  110 . The inner hook element  143 : extends across the second axial face  119  of the rotor  110 ; extends partially across the inner radial surface  116  of the rotor  110 ; and is arranged normal to the outer hook segment to define a throat configured to locate the rotor  110  within the coil assembly. Additionally, the system  100  includes a shaft  160  coupled to the inner radial surface  116  of the rotor  110  and aligned to the motor axis. Furthermore, the system  100  includes a controller  190  configured to drive current through the set of coil assemblies  131  to generate a toroidal magnetic field configured to envelop the rotor  110  and couple the set of magnetic elements  112  of the rotor  110 , thereby rotating the rotor  110  embedded within the set of coil assemblies  131 . 
     As shown in  FIGS.  7  and  8   , a variation of the system  100  includes a rotor  110  including a set of magnetic elements  112  arranged radially about a motor axis within a body  115 . The body  115  of the rotor  110  defines an inner radial surface  116 , an outer radial surface  117 , a first axial face  118 , and a second axial face  119  opposite the first axial face  118 . The system  100  further includes a stator  130  including a set of coil assemblies  131  arranged in a radial pattern about the rotor  110 . Each coil assembly in the set of coil assemblies  131  includes an outer hook element  133  including a first set of leads  155  and an inner hook element  143  including a second set of leads  156 . The outer hook element  133  extends: partially across the first axial face  118  of the rotor  110 ; and across the outer radial surface  117  of the rotor  110 . The inner hook element  143 : extends across the second axial face  119  and the inner radial surface  116  of the rotor  110 ; and is arranged normal to the outer hook element  133  to define a throat configured to locate the rotor  110  within the coil assembly. Additionally, the system  100  includes a tubular structure arranged about the first axial face  118  of the rotor  110  and aligned to the motor axis. Furthermore, the system  100  includes a controller  190  configured to drive current through the set of coil assemblies  131  to generate a toroidal magnetic field configured to envelop the rotor  110  and couple to the set of magnetic elements  112  of the rotor  110 , thereby rotating the rotor  110  while embedded within the set of coil assemblies  131 . 
     2. Applications 
     Generally, the system  100  can function as an electric motor including a stator  130  configured to direct magnetic fields across all surfaces of a rotor  110  located within the stator  130 . In particular the stator  130  includes a set of coil assemblies  131  arranged radially about the rotor  110 , each coil assembly in the set of coil assemblies  131  extending across axial faces and radial surfaces of the rotor  110 . Additionally, the rotor  110  includes a set of magnetic elements  112  arranged within a body  115  of the rotor  110  configured to couple the magnetic fields generated at the set of coil assemblies  131 . Furthermore, the system  100  can include a shaft  160 , rigidly mounted to the rotor  110  (e.g., mounted to an inner radial of rotor), and configured to rotate about a motor axis. A controller  190  can then drive current (e.g., DC current, AC current) through the set of coil assemblies  131  in order to generate these magnetic fields to then induce magnetic flux linkage between the rotor  110  and the stator  130  across all surfaces (i.e., axial faces and radial surfaces) of the rotor  110 , thereby rotating the shaft  160  rigidly mounted to the rotor  110 . 
     In one example, each coil assembly in the set of coil assemblies  131  includes an outer hook element  133  including a first set of leads  155  and an outer hook portion including a second set of leads  156 . In this example, the outer hook element  133  is formed into a first L-shaped winding structure extending across a top axial face of the rotor  110  and an outer radial face of the rotor  110 . Additionally, the inner hook element  143  is formed into a second L-shaped winding structure extending across a bottom axial face of the rotor  110  and extends across an inner radial surface  116  of the rotor  110 . The outer hook element  133 : can be connected in series with the inner hook element  143 ; and is arranged normal to the inner hook element  143  to define a throat locating the rotor  110  within the coil assembly. 
     Therefore, the system  100  can: locate the rotor  110  entirely within the set of coil assemblies  131 ; generate a toroidal-tunnel of magnetic fields coupling all surfaces of the rotor  110  in order to rotate the rotor  110  within the set of coil assemblies  131 ; and, therefore, increase speed and torque of the electric motor without increasing a quantity of copper for the set of coil assemblies  131 . 
     The system  100  can also include a housing  172  defining a cavity configured to locate the stator  130  and the rotor  110  within the housing  172 . The system  100  can also include a set of ferrous elements  181  arranged about axial and radial sides of the set of coil assemblies  131  in order to: rigidly support the stator  130  within the cavity of the housing  172 ; and define sets of stator poles configured to direct magnetic fields toward the rotor  110  within the set of coil assemblies  131 . 
     For example, the housing  172  can include: a base  173 ; an outer radial wall  174  arranged about an outer circumference of the base  173 ; an inner radial wall  175  arranged about an inner circumference of the base  173 ; and a cover  176  arranged over the base  173  and coupled to the outer radial wall  174  and inner radial wall  175  to define the cavity locating the stator  130  and rotor  110  within the housing  172 . Furthermore, the stator  130  can include a first ferrous element  182 : arranged about a bottom axial side of the set of coil assemblies  131 ; abutting with the base  173  of the housing  172 ; and defining a first set of stator poles  183  directed to the top axial face of the rotor  110 . A second ferrous element  184  is: arranged about the top axial side of the set of coil assemblies  131 ; abutting with the cover  176  of the housing  172 ; and defining a second set of stator poles  185  directed to the bottom axial face of the rotor  110 . 
     Therefore, the system  100  can: induce balanced axial forces about opposing axial forces of the rotor  110 ; and rigidly support the top and bottom axial of the stator  130  within the housing  172 , thereby reducing vertical propagation of the rotor  110  and stator  130  within the housing  172 . Furthermore, the structure of the housing  172  allows for a cooling system (e.g., liquid cooling, air cooling) to apply coolant about each surface of the housing  172 , thereby rapidly reducing an internal temperature of the housing  172 . 
     Additionally or alternatively, the system  100  can include sets of ferrous elements arranged about radial sides of the stator  130  in order to: rigidly support the stator  130  and rotor  110  within the housing  172 ; and define sets of radial stator poles directed to radial surfaces of the rotor  110 . 
     In one example application, the system  100  can function as a 25-kilowatt submerged pump motor for municipal applications configured to operate at 4500 rpm. In this implementation, the system  100  can leverage the water enveloping the submerged pump motor to internally cool the rotor  110  and stator  130  within the housing  172  during operation. 
     3. Rotor 
     Generally, the system  100   100  includes a rotor  110  including a set of magnetic elements  112  arranged radially about a motor axis within a body  115  (e.g., a toroidal cylinder fabricated from iron, nickel, cobalt, or a combination thereof). 
     In one implementation, the body  115  defines: a first axial face  118  (e.g., a front face of the electric motor), a second axial face  119  opposite the first axial face  118  (e.g., a rear face of the electric motor), an inner radial surface  116 ; and an outer radial surface  117 . The body  115  can further define a set of slots  124  fabricated (e.g., punched, cut) into the body  115  and configured to receive the set of magnetic elements  112 . Additionally, the body  115  can define a set of pole spacers  122 , each pole spacer arranged intermediately between slots of the rotor  110 . In this implementation, the set of magnetic elements  112  are arranged in an alternating pole orientation (e.g., a pseudo Halbach array) within the body  115  of the rotor  110  configured to distribute magnetic flux on each of the first axial face  118 , second axial face  119 , inner radial surface  116 , and outer radial surface  117  of the rotor  110 . 
     For example, the set of magnetic elements  112  includes a subset of magnetic elements  112  including: a first magnetic element  113  of a first pole orientation (e.g., north - south) arranged within a first slot of the rotor  110  and adjacent a first pole spacer; and a second magnetic element  114  of a second pole orientation (e.g., south - north) arranged within a second slot of the rotor  110  adjacent the first pole spacer, such that, the opposing south pole of each magnetic element are opposing each other and therefore distribute magnetic flux evenly across all four surfaces of the first pole spacer (e.g., an top surface, bottom surface, inner surface, and outer surface of the first pole spacer). Accordingly, each of the magnetic elements in the set of magnetic elements  112  can be arranged in this alternating pole orientation about the body  115  of the rotor  110 , thereby evenly distributing magnetic flux across the surfaces of the rotor  110 . Additionally, in this example, the set of pole spacers  122 : includes a set of sheets (e.g., soft metallic laminated sheets) arranged parallel to the flux distribution applied to the pole spacers and perpendicular a direction of rotation for the rotor  110 , thereby reducing the number of Eddy currents formed within the body  115  of the rotor  110 , which can reduce speed and torque of the rotor  110 . Alternatively, the set of pole spacers  122  can be manufactured from iron powders to reduce formations of Eddy currents within the body  115  of the rotor  110 . 
     Therefore, the set of magnetic elements  112  arranged within the body  115  of the rotor  110  distribute magnetic flux from the magnetic elements evenly across the first axial face  118 , second axial face  119 , inner radial surface  116 , and the outer radial surface  117  of the rotor  110 . The magnetic flux in the rotor  110  from the set of magnetic elements  112  couples with the magnetic flux generated from the set of coil assemblies  131  and therefore results in rotation of the rotor  110  within the set of coil assemblies  131 . 
     In one implementation, each magnetic element in the set of magnetic elements  112  defines a particular shape configured to cooperate with a particular shape of the set of pole spacers  122  in order to achieve even distribution of magnetic flux across the surfaces of the rotor  110 . 
     In one example, each magnetic element in the set of magnetic elements  112  defines a rectangular shape (e.g., a parallelepiped) congruent with a shape of the set of slots  124  on the body  115  of the rotor  110  that receives each of the magnetic elements. In this example, the set of pole spacers  122  arranged intermediate the set of magnetic elements  112  defines a trapezoidal shape. Therefore, the body  115  of the rotor  110  maintains a toroidal cylindrical configuration and the magnetic flux resulting from the pole orientations of the magnetic elements are distributed evenly across all surfaces of the pole spacers. Alternatively, each magnetic element in the set of magnetic elements  112  defines a trapezoidal shape and the set of pole spacers  122  arranged intermediate the set of magnetic elements  112  define a rectangular shape (e.g., a parallelepiped). 
     In one implementation, the set of magnetic elements  112  within the rotor  110  and the set of coil assemblies  131  defines a ratio wherein a quantity of magnetic elements in the set of magnetic elements  112  is greater than a quantity of coil assemblies in the set of coil assemblies  131 . In this implementation the quantity of magnetic elements and coil assemblies for this ratio depend on the desired torque and desired speed for the shaft  160 . For example, an increase in the quantity of magnetic elements in the ratio can result in an increase in torque and decrease in speed for the shaft  160 . Alternatively, a decrease in the quantity of magnetic elements in the ratio can result in a decrease in torque and increase in speed of the shaft  160 . 
     Therefore, the rotor  110  can be fabricated to achieve a target torque and a target speed with a relatively low number of magnetic elements (e.g., 20 magnetic elements), thereby reducing costs of manufacturing the system  100 . 
     3.1Shaft 
     In one implementation, as observed in  FIGS.  2  and  4   , the system  100  includes a shaft  160  in alignment with the motor axis rigidly mounted to the rotor  110 . In this implementation, the outer hook element  133  of each coil assembly couples the inner hook element  143  of each coil assembly to define a radial gap exposing a portion of the inner radial surface  116  of the rotor  110 . The system  100  can then further include a disc  161  positioned within this radial gap and defining: a diameter substantially equal to an inner diameter of the body  115  of the rotor  110 ; and a circumference rigidly coupled to the inner radial surface  116  of the rotor  110 . The shaft  160  is then rigidly coupled to the disc  161  and extends through a center of disc  161  in alignment with the motor axis, such that the shaft  160  begins to rotate in response to coupling of the magnetic elements of the rotor  110  with the magnetic field generated by the set of coil assemblies  131 . 
     In one example, the set of coil assemblies  131  can be fabricated, such that, the disc  161  positioned within the radial gap and coupled to the rotor  110  can be located: flush with a top axial face of the rotor  110 , flush with the bottom axial face of the rotor  110 , or intermediate the top axial face and the bottom axial face of the rotor  110 . In this example, the disc  161  can be either fabricated as an integral component of the rotor  110  or fabricated separately from the rotor  110  and then rigidly mounted (e.g., welded) to a particular height at the inner radial surface  116  of the rotor  110 . The set of coil assemblies  131  can then be mounted radially about the rotor  110  to define the radial gap, such that the disc  161  can rotate freely within the radial gap (i.e., without contact to the set of coil assemblies  131 ). 
     Therefore, the disc  161 : locates the shaft  160  in alignment with the motor axis of the rotor  110 ; and enables rotation of the shaft  160  about the motor axis with minimal components coupling the shaft  160  and the rotor  110 , thereby reducing loss of torque and speed of the rotating shaft  160 . 
     In one implementation, as observed in  FIG.  2   , rigidly coupling the disc  161  to the inner radial surface  116  of the rotor  110  prevents a length of the inner hook element  143  from extending entirely across the inner radial surface  116 , which results in an imbalance of radial magnetic flux along the inner radial surface  116  and outer radial surface  117  of the rotor  110 . In this implementation, the disc  161  includes a height tapering from a center of the disc  161  toward the circumference of the disc  161  rigidly coupled to the inner radial surface  116  of the rotor  110 , thereby forming a conical profile for the disc  161 . Therefore, the system  100  can: reduce transfer of the imbalance of radial forces resulting from magnetic flux coupling; and maintain the shaft  160  coupled to the rotor  110  spinning about the motor axis. 
     4. Stator 
     Generally, the system  100  includes a stator  130  including a set of coil assemblies  131 , each including an outer hook element  133  including a first set of leads  155  and an inner hook element  143  including a second set of leads  156 . The set of coil elements are arranged radially about the rotor  110  and configured to extend across each surface of the rotor  110 , thereby generating a toroidal magnetic field about the rotor  110  in order to induce magnetic flux linkage across each surface of the rotor  110  and enable rotation of the rotor  110  within the set of coil assemblies  131 . 
     4.1 Coil Assembly: Unitary Coil 
     In one implementation shown in  FIG.  3   , each coil in the set of coil assemblies  131  defines a single unitary winding extending across all surfaces of the rotor  110 . In this implementation, the outer hook element  133  and the inner hook element  143  are integrally formed into the single unitary coil winding. For example, each coil can be wound about the rotor  110  such that the coil extends across the first axial face  118 , second axial face  119 , outer radial surface  117 , and inner radial surface  116  of the rotor  110 . Additionally, each coil includes a set of leads  155  which can be connected to the controller  190  or connected to other coils in the set of coil assemblies  131  to arrange the set of coils in series and/or in parallel to each other. 
     4.2 Coil Assembly: Hook Elements 
     In one implementation shown in  FIGS.  2  and  4   , the outer hook element  133  and the inner hook element  143  of each coil assembly in the set of coil assemblies  131  defines a continuous loop of wire (e.g., laminated copper wire) extending across surfaces of the rotor  110 . In particular the outer hook element  133  and the inner hook element  143  can be connected to form a hook-wound coil profile extending across each surface of the rotor  110  and define a throat to locate the rotor  110  within the coil assembly. In this implementation, the outer hook elements  133  for the set of coil assemblies  131  can initially be mounted to the rotor  110 . The inner hook elements  143  for the set of coil assemblies  131  can then be mounted to the rotor  110  in alignment with the outer hook elements  133 , thereby locating the rotor  110  within coil assembly. The first set of leads  155  for the outer hook elements  133  can then connected in series with the second set of leads  156  for the inner hook elements  143 . 
     In one example, the outer hook element  133  of the coil assembly includes a first outer hook branch  134  and a second outer hook branch  137 . The first outer hook branch  134  defines: a first outer coil segment  135  extending across the first axial face  118  of the rotor  110 ; and a second outer coil segment  136  normal the first outer coil segment  135  and extending across the outer radial surface  117  of the rotor  110 . The second outer hook branch  137  is congruent (i.e., same shape and size) to the first outer hook branch  134  and defines: a third outer coil segment  138  parallel the first outer coil segment  135  and extending across the first axial face  118  of the rotor  110 ; and a fourth outer coil segment  139 . The fourth outer coil segment  139 : is normal to the third outer coil segment  138 ; is parallel to the second outer coil segment  136 ; and extends across the outer radial surface  117  of the rotor  110 . Furthermore, the outer hook element  133  includes: a first neutral coil segment  151  connecting the first outer coil segment  135  and the third outer coil segment  138 ; and a second neutral coil segment  152  connecting the second outer coil segment  136  and the fourth outer coil segment  139  to define a first L-shaped structure. 
     In the foregoing example, the inner hook element  143  of the coil assembly includes a first inner hook branch  144  and a second inner hook branch  147 . The first inner hook branch  144  defines: a first inner coil segment  145  extending partially across the inner radial face of the rotor  110 ; and a second inner coil segment  146 . The second inner coil segment  146 : is normal the first inner coil segment  145 ; extends across the second axial face  119  of the rotor  110 ; and is connected to the second outer coil segment  136  of the first outer hook branch  134 . The second inner hook branch  147  is congruent (i.e., same size and shape) to the first inner hook branch  144  and defines: a third inner coil segment  148  parallel the first inner coil segment  145  and extending partially across the inner radial face of the rotor  110 ; and a fourth inner coil segment  149 . The fourth inner coil segment  149 : is normal to the third inner coil segment  148 ; is parallel to the second inner coil segment  146 ; extends across the second axial face  119  of the rotor  110 ; and is connected to the fourth outer coil segment  139  of the second outer hook branch  137 . The inner hook element  143  further includes: a third neutral coil segment  153  connecting the first inner coil segment  145  and the third inner coil segment  148 ; and a fourth neutral coil segment  154  connecting the second inner coil segment  146  and the fourth inner coil segment  149  to define a second L-shaped structure arranged normal to the first L-shaped structure to define the throat locating the rotor  110  within the coil assembly. 
     Therefore, the system  100  can: locate the rotor  110  within the set of coil assemblies  131 ; drive current through the continuous loop of the coil assembly to generate a toroidal magnetic field in order to induce a balanced magnetic flux linkage on the opposing axial faces of the rotor  110 ; and thereby enable rotation of the rotor  110  within the set of coil assemblies  131 . 
     4.3 Coil Assembly: Multi-Coil Geometry 
     In one implementation of the system  100 , each coil assembly in the set of coil assemblies includes a set of coil windings: arranged across each surface of the rotor  110 ; and forms a hook profile defining a throat configured to locate the rotor  110  within the coil assembly; and including a set of leads. As a result, the controller  190  can, independently or sequentially, drive current to each coil winding in the set of coil windings, thereby generating magnetic fields directed to surfaces of the rotor  110  in order to induce magnetic flux coupling across each surface of the rotor  110 . 
     For example, the outer hook element  133  for each coil assembly in the set of coil assemblies  131  can include: a first coil winding extending across the first axial face  118  of the rotor  110  and including a first lead; and a second coil winding. The second winding: is normal to the first coil winding to define a first L-shaped structure; extends across the outer radial surface  117  of the rotor  110 ; is connected in series to the first coil winding; and includes a second lead. 
     Furthermore, the inner hook element  143  for each coil assembly in the set of coil assemblies  131  can include: a third coil winding extending partially across the inner radial surface  116  of the rotor  110  and including a third lead; and a fourth coil winding. The fourth coil winding: is normal to the third coil winding to define a second-L shaped structure cooperating with the first L-shaped structure to form the throat configured to locate the rotor  110  within the coil assembly; extends across the second axial face  119  of the rotor  110 ; is connected in series to the third coil winding; and includes a fourth lead. 
     Therefore, the system  100  can: drive current to the outer hook element  133  and the inner hook element  143  independent from each other; generate a toroidal magnetic field of varying magnetic field intensity enveloping the rotor  110 ; and thereby achieve a target magnetic flux balance across opposing axial faces of the rotor  110  and minimize magnetic flux imbalance across the inner radial surface  116  and outer radial surface  117  of the rotor  110 . 
     4.4 Stator Poles 
     In one implementation, the system  100  includes a stator  130  including a set of ferrous elements  181 : each arranged radially and axially about the set of coil assemblies  131 ; supporting the set of coil assemblies  131  to maintain the hook formation and locate the rotor  110  within the set of coil assemblies  131 ; and defining sets of stator poles generating magnetic fields directed to each surface of the rotor  110 , thereby inducing a magnetic flux linkage across surfaces of the rotor  110  in order to rotate the rotor  110  within the set of coil assemblies  131 . As a result, the rotor poles of the rotor  110  continuously attempt to align with stator poles of the stator  130 , in response to driving current through the set of coils, and thereby rotating the rotor  110  within the set of coil assemblies  131 . 
     For example, the set of ferrous elements  181  can include a first ferrous element  182 : coupled to axial coil segments of the outer hook element  133  for each coil assembly in the set of coil assemblies  131 ; defining a first set of axial stator poles configured to mate intermediate the axial coil segments of the outer hook element  133  for each coil assembly in the set of coil assemblies  131 ; and configured to generate magnetic fields at each stator  130  pole, in the first set of axial stator poles, directed to the first axial face  118  of the rotor  110 . 
     Additionally in this example, the set of ferrous elements  181  can also include a second ferrous element  184  coupled to axial coil segments of the inner hook element  143 , for each coil assembly in the set of coil assemblies  131 , opposite the axial coil segments of the outer hook element  133 . The second ferrous element  184  defines a second set of axial stator poles: arranged in alignment with the first set of axial stator poles; and configured to mate intermediate the axial coil segments of the inner hook element  143  for each coil assembly in the set of coil assemblies  131 . The second ferrous element  184  is configured to generate magnetic fields at each stator pole, in the second set of axial stator poles, directed to the second axial face  119  of the rotor  110 . In this example, the first ferrous element  182  defines a thickness similar to a thickness of the second ferrous element  184  thereby generating a balanced magnetic field directed to the first axial face  118  and the second axial face  119  of the rotor  110 . 
     In the foregoing example, the set of ferrous elements  181  can also include: a third ferrous element  186 : coupled to outer radial coil segments of the outer hook element  133 , for each coil assembly in the set of coil assemblies  131 ; defining a set of outer radial stator poles  187  of a first height configured to mate intermediate the outer radial coil segments, of the outer hook elements  133 , for each coil assembly in the set of coil assemblies  131 ; and configured to generate magnetic fields at each stator  130  pole, in the set of outer radial stator poles  187 , directed to the outer radial surface  117  of the rotor  110 . 
     Furthermore, the set of ferrous elements  181  can include a fourth ferrous element  188  coupled to inner radial coil segments of the inner hook element  143 , for each coil assembly in the set of coil assemblies  131 , opposite the outer radial coil segments of the outer hook element  133 . The fourth ferrous element  188  can define a set of inner radial stator poles  189  of a second height less than the first height of the set of outer radial stator poles  187 . The set of inner radial stator poles  189 : are arranged in alignment with the set of outer radial stator poles  187 ; and configured to mate intermediate the inner radial coil segments of the inner hook element  143 , for each coil assembly, in the set of coil assemblies  131 . The fourth ferrous element  188  is configured to generate magnetic fields at each stator  130  pole, in the set of inner radial stator poles  189 , directed to the inner radial surface  116  of the rotor  110 . In this example, the height difference of the set of outer radial stator poles  187  and the set of inner radial stator poles  189  results in an imbalance between the magnetic fields directed to the radial surfaces of the rotor  110 . 
     Therefore, the ferrous elements can: support the set of coil assemblies  131  to maintain engagement with the rotor  110 , thereby eliminating the need for a yoke to support the rotor  110 ; generate magnetic fields directed to each surface of the rotor  110  to increase speed and torque output by the shaft  160 ; and induce balanced axial forces across each axial face of the rotor  110 , thereby axially stabilizing the rotor  110  when rotating within the set of coil assemblies  131 . 
     In one implementation, each ferrous element in the set of ferrous elements  181  can include a set of laminated ferrous sheets arranged parallel a magnetic flux distribution induced on the ferrous element and perpendicular a direction of rotation for the rotor  110 , thereby reducing the number of Eddy currents formed on the ferrous element. In one example, the ferrous element can be fabricated by stacking parallel rings of laminated ferrous sheet to achieve a particular height and thickness for the set of stator poles. In another example, the ferrous element can be fabricated by compressing a strip of ferrous material into a helical spring, thereby forming the set of laminated ferrous sheets for the ferrous element. 
     Additionally or alternatively, the ferrous elements can be manufactured from iron powders. 
     4.5 Coil Arrangement: 180 Degrees 
     In one implementation observed in  FIG.  9   , the set of coil assemblies  131  can include subsets of coil assemblies arranged to form a three-phase configuration (e.g., delta configuration, wye configuration) for the stator  130 . In this implementation, these subsets of coil assemblies can include coil assemblies connected in series to each other and arranged at opposing angular offsets (i.e., 180-degree offset) about the rotor  110 . As a result, the controller  190  can then be configured to sequentially drive current to these subsets of coil assemblies in order to sequentially generate the magnetic fields directed to the surfaces of the rotor  110 . 
     For example, the set of coil assemblies  131  can include a first subset of coil assemblies  131  including: a first coil assembly  132 ; and a second coil assembly  157  connected in series with the first coil assembly  132  and arranged 180 degrees opposite the first coil assembly  132 . Additionally, the set of coil assemblies  131  can include a second subset of coil assemblies  131  including: a third coil assembly  158  angularly offset from the first coil assembly  132 ; and a fourth coil assembly  159  arranged 180 degrees opposite the third coil assembly  158  and connected in series with the third coil assembly  158 . In this example, the controller  190  can then sequentially drive current to the first subset of coil assemblies  131  and the second subset of coil assemblies  131  to sequentially generate magnetic fields about the rotor  110  that couple the set of magnetic elements  112  in the rotor  110  to enable rotation of the rotor  110 . 
     Additionally, the set of coil assemblies  131  can also include a third subset of coil assemblies  131  arranged in a similar configuration as described above to form the three-phase configuration for the set of coil assemblies  131  of the stator  130 . 
     Therefore, the system  100  can: sequentially generate opposing magnetic fields at the set of coil assemblies  131  directed to each surface of the rotor  110 , in order to sequentially induce magnetic flux coupling to the rotor  110  within the set of coil assemblies  131 , and thereby continuously urge the rotor  110  poles of the rotor  110  to align with the stator poles of the stator  130  to rotate the rotor 110within the set of coil assemblies  131 . 
     4.6 Coil Arrangement: 120 Degrees 
     In one implementation observed in  FIG.  10   , the subsets of coil assemblies can include coil assemblies connected in series to each other and arranged at 120-degree offsets about the rotor  110 . As a result, the controller  190  can then be configured to sequentially drive current to these subsets of coil assemblies in order to sequentially generate the magnetic fields directed to the surfaces of the rotor  110 . 
     For example, the set of coil assemblies  131  can include a first subset of coil assemblies  131  including: a first coil assembly  132 ; and a second coil assembly  157  connected in series with the first coil assembly  132  and arranged adjacent the first coil assembly  132 . Additionally, the set of coil assemblies  131  includes a second subset of coil assemblies  131  including: a third coil assembly  158  angularly offset 120 degrees from the first coil assembly  132 ; and a fourth coil assembly  159  connected in series with the third coil assembly  158  and arranged adjacent the third hook assembly. In this example, the controller  190  can then be configured to sequentially drive current to the first subset of coil assemblies  131  and the second subset of coil assemblies  131  to sequentially generate magnetic fields about the rotor  110  that couple the set of magnetic elements  112  and enable rotation of the rotor  110  within the set of coil assemblies  131 . 
     Additionally, the set of coil assemblies  131  can also include a third subset of coil assemblies  131  arranged in a similar configuration as described above to form the three-phase configuration for the stator  130 . 
     Therefore, the system  100  can: sequentially generate magnetic fields at offsets of 120-degrees directed to each surface of the rotor  110 , in order to sequentially induce magnetic flux coupling to the rotor  110  within the set of coil assemblies  131 , and thereby continuously urge the rotor poles of the rotor  110  to align with the stator poles of the stator  130  to rotate the rotor  110  within the set of coil assemblies  131 . 
     Coil Leads 
     In one implementation, the first set of leads  155  of the outer hook element  133  is connected in series with a second set of leads  156  for the inner hook element  143 . For example, the first set of leads  155  can include a start lead and a first connecting lead. Additionally, the second set of leads  156  can include a second connecting lead and an end lead. In this example, the first connecting lead and the second connecting lead can be connected in series, thereby connecting the outer hook element  133  and the inner hook element  143  in series. Therefore, the set of coil assemblies  131  includes a start lead and an end lead; and the controller  190  can drive a current signal through the start lead to generate magnetic fields at the outer hook element  133  and the inner hook element  143 . 
     In this example, a three-phase configuration including a first subset of coil assemblies  131 , a second subset of coil assemblies  131 , and a third subset of coil assemblies  131  will result in a set of 3 start leads and 3 end leads for a total of 6 leads. 
     In another implementation, the first set of leads  155  of the outer hook element  133  is connected parallel with the second set of leads  156  of the inner hook element  143 . For example, the first set of leads  155  can include a first start lead and a first end lead each connected to the controller  190 . Additionally, the second set of leads  156  can include a second start lead and a second end lead, each connected to the controller  190 . Therefore, the controller  190  can: drive a first current signal of a first amplitude through the first set of leads  155  to generate a first magnetic field of a first strength at the outer hook element  133 ; and drive a second current signal of a second amplitude, greater than the first amplitude, through the second set of leads  156  to generate a second magnetic field of a second strength at the inner hook element  143 ; and thereby direct magnetic fields of varying field strength across all surfaces of the rotor  110 . 
     In the aforementioned example, a three-phase configuration including a first subset of coil assemblies  131 , a second subset of coil assemblies  131 , and a third subset of coil assemblies  131  will result in a set of 6 start leads and 6 end leads for a total of 12 leads 
     In this implementation, the set of leads can be grouped together and connected to a terminal casing, which can be located externally from the rotor  110  and stator  130 . The leads in the terminal casing can then be configured into a particular three-phase configuration (e.g., delta connection, wye connection) for the subsets of coil assemblies. Therefore, the system  100  can group all connections for the stator  130  to a particular location and thereby mitigate exposure to elements (e.g., water) and conditions (e.g., high-temperatures), which can compromise operation of the system  100 . 
     5. Housing 
     In one implementation, the system  100  includes a housing  172  defining a cavity locating the rotor  110  and the stator  130  within the cavity of the housing  172 . In this implementation the housing  172  supports the set of ferrous elements  181  of the stator  130  on all sides (i.e., axial sides and radial sides) in order to secure the rotor  110  within the set of coil assemblies  131  and mitigate radial imbalances resulting from offset magnetic flux linkage induced from the inner radial stator poles and the outer radial stator poles. 
     For example, the housing  172  can include: a base  173  defining an inner circumference and an outer circumference; an inner radial wall  175  arranged about the inner circumference of the base  173 ; an outer radial wall  174  arranged about the outer circumference of the base  173 ; and a cover  176  arranged over the inner radial wall  175  and the outer radial wall  174  opposite the base  173  and defining the cavity within the housing  172 . Therefore, in this example, the housing  172  can define a toroidal cylinder with the cavity configured to locate the rotor  110  and stator  130  within the housing  172 . 
     Furthermore, in this example, to maintain the set of coil assemblies  131  in engagement with the rotor  110 , the stator  130  within the cavity of the housing  172  can locate: the first ferrous element  182  in abutting engagement with the cover  176  of the housing  172 ; the second ferrous element  184  in abutting engagement with the base  173  of the housing  172 ; the third ferrous element  186  in abutting engagement with the outer radial wall  174  of the housing  172 ; and the fourth ferrous element  188  in abutting engagement with the inner radial wall  175  of the housing  172 . 
     Therefore, the housing  172 : rigidly locates the stator  130  and the coil within the cavity of the housing  172 ; and can eliminate the need for a yoke mounted to the rotor  110  in order to support the rotor  110  within the housing  172 . Furthermore, the housing  172  can stabilize the offset imbalanced radial forces of the rotor  110 , resulting from the set of inner radial stator poles  189  and outer radial stator poles, by rigidly supporting the stator  130  between the inner radial wall  175  and outer radial wall  174  of the housing  172 . 
     Additionally, the system  100  can include an external cooling system (e.g., air cooling, liquid cooling) configured to apply coolant to outer surfaces of the housing  172  and thereby reduce the internal temperature of the housing  172  due to convection between the housing  172  and the internally located rotor  110  and stator  130 . 
     In one implementation, the inner radial gap of the housing  172  defines a radial gap in alignment with the radial gap formed by the set of coil assemblies  131  mounted about the stator  130 . In this implementation, the disc  161  can extend through the radial gap of the housing  172  and the radial gap of the set of coil assemblies  131  in order to rigidly couple the inner radial surface  116  of the rotor  110 . 
     In one implementation, the set of leads for the set of coil assemblies  131  can be grouped together and connected to an internal terminal casing located within the cavity of the housing  172  or connected to an external terminal casing mounted to an outer surface of the housing  172 . 
     6. Controller 
     In one implementation, the system  100  includes the controller  190  configured to drive current (e.g., AC current, DC current) through the set of coil assemblies  131  to generate a magnetic field at the set of stator poles coupling the magnetic elements within the body  115  of the rotor  110 , thereby rotating the rotor  110  within the set of coil assemblies  131 . 
     In one example, the controller  190  can be configured to switch polarity of current supplied to the set of coil assemblies  131  in order to enable rotation of the rotor  110 . Furthermore, the controller  190  can be configured to modulate frequency and amplitude of the current supplied to the set of coil assemblies  131 , thereby modifying speed and direction of rotation for the shaft  160  coupled to the rotor  110  in order to satisfy a particular mode of operation (e.g., pump motor operation, vehicle motor operation) for the electric motor. 
     7. Example: Submerged Pump Motor 
     In one implementation, the system  100  is configured to function as a submerged pump motor, such as a 4500-rpm pump motor operating at 25 kilowatts, for municipal applications. In this implementation, the housing  172  is submerged in water and, therefore, the rotor  110  and stator  130  within the cavity of the housing  172  must be sealed within the housing  172  to prevent water from interacting with the set of stator coils resulting in failure of operation for the motor. The cavity of the housing  172  can then be filed with a lubricating fluid (e.g., silicon oil) configured to fill the cavity within the housing  172  and envelop the rotor  110  and stator  130  within the housing  172 . 
     In one example, the housing  172  includes: a base  173 ; an outer radial wall  174  extending from the base  173 ; and a cover  176  arranged over the base  173  and coupled to the outer radial wall  174  extending from the base  173  to define a cavity configured to locate the rotor  110  and the stator  130  within the housing  172 . Additionally, the housing  172  can include: a first inner radial wall extending from the base  173 ; and a second inner radial wall extending from the cover  176  to define a radial gap in alignment with the radial gap formed by the set of coil assemblies  131  exposing a portion of the inner radial surface  116  of the rotor  110 . 
     In this example, the disc  161 , rigidly coupled to the inner radial surface  116  of the rotor  110  and supporting the shaft  160 , is positioned within the radial gap of the housing  172  and the radial gap formed by the set of coil assemblies  131 . As a result, the radial gap along the inner radial wall  175  of the housing  172  can allow for water to enter the cavity of the housing  172  and, thereby, short stator  130  within the housing  172 . To prevent water from entering through this radial gap, the system  100  can include: a first bearing  177  arranged about the first inner radial wall of the housing  172  and coupled to a first face of the disc  161 ; and a second bearing  178  arranged about the second inner radial wall of the housing  172  and coupled to a second face of the disc  161  opposite the first face. 
     Therefore, the bearings coupled to the housing  172  enable the disc  161  to rotate freely about the inner radial of the housing  172  while sealing the radial gap of the housing  172 , thereby preventing liquids and debris from entering the cavity of the housing  172  and interacting with the stator  130  within the housing  172 . 
     Furthermore, the fluid (e.g., silicon oil) is disposed within the housing  172  and configured to fill the cavity locating the rotor  110  and the stator  130  within the housing  172 . Therefore, in the event of the water entering the cavity of the housing  172 , the density of the fluid within the cavity will prevent water from interacting with the stator  130  located within the housing  172 . 
     8. Variation: Tubular Shaft 
     In one variation, as observed in  FIGS.  7  and  8   , the system  100  includes a tubular shaft  162  rigidly mounted to the first axial face  118  of the rotor  110 . In this implementation, the outer hook element  133  of each coil assembly couples the inner hook element  143  of each coil assembly to define a radial gap exposing a portion of the first axial face  118  of the rotor  110 . The tubular shaft  162  can then be positioned within this radial gap and defines: a shaft  160  diameter greater than an inner diameter of the rotor  110  and less than an outer diameter of the rotor  110 ; and a first end rigidly coupled to the first axial face  118  of the rotor  110 . The tubular shaft  162 , rigidly coupled to the rotor  110 , rotates about the motor axis in response to coupling of the magnetic elements of the rotor  110  with the magnetic field generated by the set of coil assemblies  131 . 
     8.1 Coil Assembly: Tubular Shaft 
     In one implementation of this variation of the system  100 , each coil assembly in the set of coil assemblies  131  includes: an outer hook element  133  including a first set of leads  155  and an inner hook element  143  including a second set of leads  156 . The inner hook element  143  is arranged normal to the outer hook portion to define a throat locating the rotor  110  within the set of coil assembly. In this variation, the outer hook element  133  and the inner hook element  143  extend across each surface of the rotor  110  to generate a toroidal magnetic field in order to induce: a balanced magnetic flux linkage across the inner radial surface  116  and outer radial surface  117  of the rotor  110 ; and an imbalanced magnetic flux linkage across opposing axial faces of the rotor  110 . 
     For example, the outer hook element  133  for the coil assembly includes a first outer hook branch  134  and a second outer hook branch  137 . The first outer hook branch  134  defines: a first outer coil segment  135  extending partially across the first axial face  118  of the rotor  110 ; and a second outer coil segment  136  normal to the first outer coil segment  135  and extending across the outer radial surface  117  of the rotor  110 . The second outer hook branch  137  is congruent (i.e., same shape and size) to the first outer hook branch  134  and defines: a third outer coil segment  138  parallel to the first outer coil segment  135  and partially extending across the first axial face  118  of the rotor  110 ; and a fourth outer coil segment  139 . The fourth outer coil segment  139 : is normal to the third outer coil segment  138 ; is parallel to the second outer coil segment  136 ; and extends across the outer radial surface  117  of the rotor  110 . The outer hook element  133  further includes: a first neutral coil segment  151  connecting the first outer coil segment  135  and the third outer coil segment  138 ; and a second neutral coil segment  152  connecting the second outer coil segment  136  and the fourth outer coil segment  139  to define a first L-shaped structure. 
     In this foregoing example, the inner hook element  143  for the coil assembly includes a first inner hook branch  144  and a second inner hook branch  147 . The first inner hook branch  144  defines: a first inner coil segment  145  extending across the inner radial face of the rotor  110 ; and a second inner coil segment  146 . The second inner coil segment  146 : is normal to the first inner coil segment  145 ; and extends across the second axial face  119  of the rotor  110 . The second inner hook branch  147  is congruent (i.e., same shape and size) to the first inner hook branch  144  and defines: a third inner coil segment  148  parallel to the first inner coil segment  145  and extending across the inner radial face of the rotor  110 ; and a fourth inner coil segment  149 . The fourth inner coil segment  149 : is normal to the third inner coil segment  148 ; is parallel to the second inner coil segment  146 ; and extends across the second axial face  119  of the rotor  110 . The inner hook element  143  further includes a third neutral coil segment  153  connecting the first inner coil segment  145  and third inner coil segment  148 ; and a fourth neutral coil segment  154  connecting the second inner coil segment  146  and the fourth inner coil segment  149  to define a second L-shaped structure arranged normal to the first L-shaped structure to define the throat locating the rotor 110within the coil assembly. 
     Therefore, the system  100  can: locate the rotor  110  within the set of coil assemblies  131 ; drive current through the continuous loop of the coil assembly to generate a toroidal magnetic field in order to induce a balanced magnetic flux linkage on the inner radial surface  116  and outer radial surface  117  of the rotor  110 ; and, thereby, enable rotation of the rotor  110  within the set of coil assemblies  131 . 
     8.2 Stator Poles: Tubular Shaft 
     In one implementation, as described above, the system  100  includes a stator  130  including a set of ferrous elements  181 : each arranged radially and axially about the set of coil assemblies  131 ; supporting the set of coil assemblies  131  to maintain the hook formation and locate the rotor  110  within the set of coil assemblies  131 ; and defining sets of stator poles generating magnetic fields directed to each surface of the rotor  110 , thereby inducing a magnetic flux linkage across surfaces of the rotor  110  in order to rotate the rotor  110  within the set of coil assemblies  131 . In this variation of the system  100 , the ferrous elements arranged about an outer radial and inner radial of the set of coil assemblies  131  define a similar height, such that balanced radial forces are applied to the rotor  110 . Furthermore, the ferrous elements arranged about the top axial side and bottom axial side of the set of coil assemblies  131  each define a particular thickness, such that imbalanced axial forces are applied to the rotor  110 . 
     For example, the set of ferrous elements  181  can include a first ferrous element  182 : coupled to axial coil segments of the outer hook element  133 , for each coil assembly in the set of coil assemblies  131 ; defining a first set of axial stator poles of a first thickness configured to mate intermediate the axial coil segments, of the outer hook element  133 , for each coil assembly in the set of coil assemblies  131 ; and configured to generate magnetic fields at each stator  130  pole, in the first set of axial stator poles, directed to the first axial face  118  of the rotor  110 . 
     Additionally, the set of ferrous elements  181  can include a second ferrous element  184 : coupled to axial coil segments of the inner hook element  143 , for each coil assembly in the set of coil assemblies  131 , opposite the axial coil segments of the outer hook element  133 ; and defining a second set of axial stator poles of a second thickness greater than the first thickness of the first set of axial stator poles. The second set of axial stator poles: are arranged in alignment with the first set of axial stator poles; and configured to mate intermediate the axial coil segments of the inner hook element  143 , for each coil assembly, in the set of coil assemblies  131 . In this example, the second set of axial stator poles are configured to generate magnetic fields at each stator  130  pole, in the second set of axial stator poles, directed to the second axial face  119  of the rotor  110 , and, thereby, induces an imbalanced magnetic flux linkage across axial faces of the rotor  110 . 
     In the foregoing example, the set of ferrous elements  181  can include a third ferrous element  186 : coupled to outer radial coil segments of the outer hook element  133 , for each coil assembly in the set of coil assemblies  131 ; defining a set of outer radial stator poles  187  configured to mate intermediate the outer radial coil segments of the outer hook element  133 , for each coil assembly, in the set of coil assemblies  131 ; and configured to generate magnetic fields at each stator  130  pole, in the set of outer radial stator poles  187 , directed to the outer radial surface  117  of the rotor  110 . 
     Furthermore, the set of ferrous elements  181  can include a fourth ferrous element  188 : coupled to inner radial segments of the inner hook element  143 , for each coil assembly in the set of coil assemblies  131 , opposite the outer radial segments of the outer hook element  133 ; and defining a set of inner radial stator poles  189 . The set of inner radial stator poles  189 : are arranged in alignment with the set of outer radial stator poles  187 ; and configured to mate intermediate the inner coil segments of the inner hook element  143  for each coil assembly, in the set of coil assemblies  131 . In this example, the set of inner radial stator poles  189  are configured to generate magnetic fields at each stator  130  pole, in the set of inner radial stator poles  189 , directed to the inner radial surface  116  of the rotor  110 , and thereby induces a balanced magnetic flux linkage across radial surfaces of the rotor  110 . 
     Therefore, in this variation of the system  100 , the ferrous elements can: support the set of coil assemblies  131  to maintain engagement with the rotor  110 , thereby eliminating the need for a yoke to support the rotor  110 ; generate magnetic fields directed to each surface of the rotor  110  to increase speed and torque output by the shaft  160 ; and induce balanced radial forces across each radial face of the rotor  110 , thereby stabilizing the rotor  110  in the radial direction when rotating within the set of coil assemblies  131 . 
     8.3 Housing: Tubular Shaft 
     In one implementation, the system  100  can include a housing  172 : locating the tubular structure on a top axial face of the housing  172 ; and configured to stabilize imbalanced axial forces of the rotor  110  resulting in vertical propagation of the rotor  110  within the cavity of the housing  172 . 
     In one example, the housing  172  can include: a base  173  defining an inner circumference and an outer circumference; an inner radial wall  175  arranged about the inner circumference of the base  173 ; an outer radial wall  174  arranged about the outer circumference of the base  173 ; and a cover  176  arranged over the inner radial wall  175  and the outer radial wall  174  opposite the base  173  and defining a cavity within the housing  172  and a radial gap cooperating with a radius of the tubular structure. 
     In this example, the stator  130  is located within the housing  172  and locates: the first ferrous element  182  in abutting engagement with the cover  176  of the housing  172 ; the second ferrous element  184  in abutting engagement with the base  173  of the housing  172 ; the third ferrous element  186  in abutting engagement with the outer radial wall  174  of the housing  172 ; and the fourth ferrous element  188  in abutting engagement with the inner radial wall  175  of the housing  172 . 
     As described above, the varying thickness of the first ferrous element  182  and the second ferrous element  184  results in offset axial forces acting upon the rotor  110  within the set of coil assemblies  131 , causing the rotor  110  and stator  130  to propagate vertically within the housing  172 . Therefore, the tubular structure can extend through the radial gap and couple to the cover  176  via a thrust bearing  179  configured to stabilize vertical propagation of the rotor  110  resulting from imbalanced axial forces. 
     The systems and methods described herein can be embodied and/or implemented at least in part as a machine configured to receive a computer-readable medium storing computer-readable instructions. The instructions can be executed by computer-executable components integrated with the application, applet, host, server, network, website, communication service, communication interface, hardware/firmware/software elements of a user computer or mobile device, wristband, smartphone, or any suitable combination thereof. Other systems and methods of the embodiment can be embodied and/or implemented at least in part as a machine configured to receive a computer-readable medium storing computer-readable instructions. The instructions can be executed by computer-executable components integrated by computer-executable components integrated with apparatuses and networks of the type described above. The computer-readable medium can be stored on any suitable computer readable media such as RAMs, ROMs, flash memory, EEPROMs, optical devices (CD or DVD), hard drives, floppy drives, or any suitable device. The computer-executable component can be a processor but any suitable dedicated hardware device can (alternatively or additionally) execute the instructions. 
     As a person skilled in the art will recognize from the previous detailed description and from the figures and claims, modifications and changes can be made to the embodiments of the invention without departing from the scope of this invention as defined in the following claims.