Abstract:
A magnetic component and transformer made therefrom is provided. The magnetic component includes an outer circular wall including a first gap and a second gap; an inner circular wall including a third gap and a fourth gap; and a cylindrical core. The outer circular wall, the inner circular wall, and the cylindrical core are concentric to one another. The outer circular wall and the inner circular wall are spaced apart to define an outer radial channel. The inner circular wall and the cylindrical core are spaced apart to define an inner radial channel. A transformer is formed by wrapping a first winding about the inner circular wall and a second winding around the cylindrical core.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Patent Application No. 61/815,096 filed on Apr. 23, 2013 and U.S. Provisional Patent Application No. 61/920,100 filed on Dec. 23, 2013, which are incorporated by reference herein in their entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    Embodiments of the present disclosure relate generally to transformers and, in particular, a highly integrated magnetic component for a transformer. 
         [0004]    2. Description of the Related Art 
         [0005]    Transformers are used in a variety of devices to perform functions such as altering a voltage level, circuit isolation, measuring voltage or current in electrical power systems, and a host of other functions. In order to provide sufficient space for the windings, the winding area of a transformer is generally large as compared to a cross-sectional area of the transformer&#39;s core, resulting in a large form-factor. In some instances, the transformer occupies valuable usable space because of the large form factor. 
         [0006]    Therefore, there is a need in the art for a space efficient, compact transformer having magnetic components that are small and compact. 
       SUMMARY OF THE INVENTION 
       [0007]    Embodiments of the present invention generally relate to transformers and a highly integrated magnetic component. 
         [0008]    Various advantages, aspects and novel features of the present disclosure, as well as details of an illustrated embodiment thereof, will be more fully understood from the following description and drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. 
           [0010]      FIG. 1  is an isometric view of a transformer formed by stacking two integrated magnetic portions in accordance with an embodiment of the present invention; 
           [0011]      FIG. 2  is a side view formed by stacking a first integrated magnetic portion and a second integrated magnetic portion to form a transformer in accordance with an embodiment of the present invention; 
           [0012]      FIG. 3  is an illustration from a cross-sectional view of the transformer of  FIG. 2  in accordance with an embodiment of the present invention; 
           [0013]      FIG. 4  is an isometric illustration of a first integrated magnetic portion and a second integrated magnetic portion of the integrated magnetic component in accordance with an embodiment of the present invention; 
           [0014]      FIG. 5  is an isometric illustration of a portion of an integrated magnetic component in accordance with an embodiment of the present invention; 
           [0015]      FIG. 6  is an illustration from a top view of the portion of the integrated magnetic component in  FIG. 5  in accordance with an embodiment of the present invention; 
           [0016]      FIG. 7  is an isometric illustration from a back view of the portion of the integrated magnetic component in  FIG. 5  in accordance with an embodiment of the present invention; and 
           [0017]      FIG. 8  is an illustration from a top view of a portion of the integrated magnetic component in accordance with an alternative embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    Embodiments of the present invention comprise a magnetic component having a unitary magnetic body comprising concentric radial channels. The channels define cores for primary and secondary windings. As will be discussed herein, the channels and respective windings form a compact, space efficient transformer. 
         [0019]      FIG. 1  is an isometric view of a transformer  100  formed by stacking two integrated magnetic portions in accordance with an embodiment of the present invention. The transformer  100  is mounted to a substrate  102 . 
         [0020]    The transformer  100  comprises a first integrated magnetic portion  106  (i.e., a top magnetic component, hereinafter referred to as first portion  106 ) and respective windings coupled to a second integrated magnetic portion  108  (i.e., a base magnetic component, hereinafter referred to as second portion  108 ) and respective windings. A first winding (i.e., a primary coil winding) and a second winding (i.e., a secondary coil winding) exit respective gaps  110  and  112  and are coupled to external circuitry (not shown). A plurality of fastener clips  104  are coupled to a plurality of fastener notches  120  on a backside of the first portion  106 . The plurality of fastener clips  104  couple the faces of the first and second portions  106  and  108  together and, in some embodiments, couples to a corresponding fastener notch located on an underside of the second portion  108 . In some embodiments, the plurality of fastener clips  104  may instead be coupled to the substrate  102  or other securing base. 
         [0021]      FIG. 2  shows a side view of the transformer  100  in accordance with an embodiment of the present invention.  FIG. 3  shows a cross section of the transformer  100  shown in  FIG. 2  taken along the line  3 - 3 . 
         [0022]    As illustrated in  FIGS. 2 and 3 , the transformer  100  is formed by coupling the face of the first portion  106  to the face of the second portion  108 . The first portion  106  is coupled to the second portion  108  such that an outer circular wall  302  and a cylindrical core  306  of the first portion  106  are in contact with a second outer circular wall  322  and a second cylindrical core  326  of the second portion  108 , respectively. An inner circular wall  304  of the first portion  106  and a second inner circular wall  324  of the second portion  108  face one another but are separated by an air gap  350 . A first winding bobbin  312  is seated in an outer radial channel  308  of the first portion  106  and extends into a second outer radial channel  328  of the second portion  108 . A first coil winding  202  is wrapped around the first winding bobbin  312 . A second winding bobbin  332  is seated in a second inner radial channel  330  of the second portion  108  and extends into an inner radial channel  310  of the first portion  106 . A second coil winding  204  is wrapped around the second winding bobbin  332 . In some embodiments, the second winding bobbin  332  occupies the entirety of the inner radial channel  310  and the second inner radial channel  330  while the first winding bobbin  312  partially extends into the second outer radial channel  328  to allow the second coil winding  204  to pass beneath it and exit the transformer  100 , as illustrated in  FIG. 3 . Although the first portion  106  and the second portion  108  are illustrated as the top and bottom portions, respectively, it should be noted that this orientation may be reversed. Similarly, the first coil winding  202  may be either of the primary or secondary coil winding and the second coil winding  204  may be the other of the primary or secondary coil winding. 
         [0023]    In some embodiments, the first coil winding  202  may comprise a copper trace on a substrate (e.g., polyamide, fiberglass, FR4, etc.) and the second coil winding  204  may comprise copper wire and may be insulated (e.g., such as Litz wire). In some embodiments, the first coil winding  202  may be a single loop and the second coil winding  204  may be a plurality (e.g., 8) of loops. However, it should be noted that the first and second coil windings  202 ,  204  may be formed of any conductive material and may include any number of loops sufficient to perform the functionality of the present invention. The bobbins  312 ,  332  are typically cylindrical and may include upper and lower flanges. The diameter of the bobbins  312 ,  332  are substantially are substantially equal to the diameters of their respective channels and in some embodiments comprise a plastic or other non-conductive material. The bobbins  312 ,  332  are press fit around their respective cores to ensure that they remain in place. Alternatively, in some embodiments, an adhesive may be used to ensure that the bobbins  312 ,  332  remain in place. In the embodiments in which the second winding bobbin  332  occupies the entirety of the inner radial channel  310  and the second inner radial channel  330  and the first winding bobbin  312  partially extends into the second outer radial channel  328 , the secondary winding bobbin  332  is held in place by both portions  106 ,  108  and the first winding bobbin  312  is held in place by the second coil winding  204  that passes beneath first winding bobbin  312  to exit the transformer  100 . The first portion  106  and second portion  108  may be formed of ferrite, manganese zinc ceramic, and the like. A cross section of the cores, walls, and channels, are substantially square or rectangular, however alternative embodiments may be rounded. 
         [0024]      FIG. 4  is an isometric illustration of the first portion  106  and the second portion  108  of the integrated magnetic component in accordance with an embodiment of the present invention. The first portion  106  includes the first coil winding  202  wound around the first winding bobbin  312 . The first winding bobbin  312  is seated into the outer radial channel  308 . The first winding bobbin  312  is thus located between the outer circular wall  302  and the inner circular wall  304 . The ends of the first coil winding  202  are seated and pass through a first gap  402  in the outer circular wall  302 . 
         [0025]    The second portion  108  includes a substantially symmetrical structure to that of the first portion  106 . The second portion  108  includes the second outer circular wall  322 , the second inner circular wall  324 , and the second cylindrical core  326 . The second portion  108  further comprises the second coil winding  204  wound around the second winding bobbin  332 . The second winding bobbin  332  is seated in the second inner radial channel  330  located between the second inner circular wall  324  and the second cylindrical core  326 . The second outer radial channel  328  is located between the second outer circular wall  322  and the second inner circular wall  324 . The ends of the second coil winding  204  pass through a second gap  404  in the second inner circular wall  324  and exit the second portion  108  via a third gap  406  in the second outer circular wall  322 . 
         [0026]    The following description will be made in reference to  FIGS. 5 and 6 .  FIG. 5  is an isometric illustration of a portion  500  of an integrated magnetic component in accordance with an embodiment of the present invention.  FIG. 6  is an illustration from a top view of the portion  500  of the integrated magnetic component in  FIG. 5 . In some embodiments, the portion  500  is substantially circular. However, it should be noted that the portion  500  may have any shape capable of performing the functions disclosed herein. The portion  500  includes an outer wall  502 , an inner wall  504  disposed within the outer wall  502 , and a cylindrical core  506  disposed within the inner wall  504 , all of which extend from a base  520 . In some embodiments, the outer wall  502 , the inner wall  504 , and the cylindrical core  506  are concentric to one another. 
         [0027]    The outer wall  502  may include a first gap  508  and a second gap  510 . The inner wall  504  may include a third gap  512  and a fourth gap  514  which are aligned with the first and second gaps  508 ,  510 , respectively. The first gap  508  and the second gap  510  are offset by 90 degrees around the center of the cylindrical core  506 . In alternative embodiments, the first gap  508  and second gap  510  are offset by a different angle or located on opposite sides of the portion  500  (e.g.,  FIG. 4 ). Although the outer wall  502  is illustrated with two gaps  508 ,  510 , it should be noted that the outer wall  502  may include any number of gaps (i.e., one or more) that allows cables within the integrated magnetic component to couple to external circuitry. The first and second gaps  508 ,  510  couple to an outer radial channel  516  defined between the outer wall  502  and the inner wall  504 . The first and second gaps  508 ,  510  also couple to an inner radial channel  518  defined between the inner wall  504  and the cylindrical core  506  via the third and fourth gaps  512 ,  514 . 
         [0028]    The outer walls  502  and cylindrical core  506  may be of substantially the same height so when the portion  500  is stacked onto a second portion, the assembly forms a substantially flush contact between corresponding outer walls and cores to house cabling (not shown). The inner wall  504  may be shorter than the outer wall  502  and the cylindrical core  506  so when the portion  500  is stacked onto the second portion, the assembly forms an air gap between the corresponding inner walls, as previously explained. In some embodiments, the walls may be annular, circular, or comprise a shape with rounded edges. 
         [0029]    In some embodiments, a first cabling may be looped around the cylindrical core  506  through the first and third gaps  508  and  512  and a second cabling may be looped around the inner wall  504  (of another portion) through the second gap  510 . During assembly, each respective cabling may be looped on opposite facing portions before stacking. Alternatively, cabling may be wrapped around a bobbin (not shown) before stacking. In another embodiment, a first and second cabling may be wrapped around the corresponding cylindrical cores of the respective top and base portions and respectively extend through gap pairs  508 / 512  and  510 / 514 . The cabling may be a braided cable or twisted wire. 
         [0030]      FIG. 7  is an isometric illustration from a back view of the portion  500  of the integrated magnetic component in  FIG. 5  in accordance with an embodiment of the present invention. The base  520  may include fastener notches  602  which are used to couple two portions together to form a transformer, as shown in  FIG. 1  and described above. 
         [0031]      FIG. 8  is an illustration from a top view of an integrated magnetic portion  800  in accordance with an alternative embodiment of the present invention. The portion  800  is substantially similar to the portion  500  of  FIG. 5  and includes an outer wall  802 , an inner wall  804 , and a cylindrical core  806 . However, the portion  800  additionally includes a sensor post  850  that replaces one of the inner gaps formed in the inner wall  804 . A description of elements of the portion  800  that are similar to those of the portion  500  will be omitted here for the sake of conciseness. The sensor post  850  is of substantially the same height as the outer wall  802  and the cylindrical core  806  so that when the portion  800  is stacked onto another portion, the sensor posts, outer walls, and cylindrical cores of the two portions are in substantially flush contact. 
         [0032]    The sensor post  850  forms a core around which a current sensor coil winding (not shown) is wrapped. The wrapping of the current sensor coil winding may be similar to that of the winding of the first and second coil windings  202 ,  204  described above with respect to  FIG. 3 . That is, the current sensor coil winding may be wound around a current sensor bobbin, which is seated around the sensor post  850 . The ends of the current sensor coil winding pass through the nearest gap in the outer wall  802 . The current sensor coil winding may be of a thinner gauge than that of the first and second coil windings  202 ,  204 . With the thinner gauge coil, the current sensor coil winding may exit the portion  800  using the same gap as the first or second coil winding without electrically or mechanically interfering with the first or second coil winding. Sensor circuitry (not shown) is coupled to the sensor coil winding and the sensor circuitry measures the current of the primary winding (i.e., the current sensor winding yields a measurable current that is indicative of the primary current on the winding of the primary coil winding). 
         [0033]    The foregoing description of embodiments of the invention comprises a number of elements, devices, circuits and/or assemblies that perform various functions as described. These elements, devices, circuits, and/or assemblies are exemplary implementations of means for performing their respectively described functions. 
         [0034]    While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof.