Low and medium voltage inductors

Abstract

The present disclosure provides a gapless medium-voltage inductor including a magnetic core having an opening extending therethrough, a bobbin having a first plate and a second plate, a spacer disposed within the opening of the magnetic core, a longitudinal path defined through the spacer, the first plate, and the second plate, and a coil extending through the longitudinal path and wound around the core and the bobbin. The core is disposed between the first plate and the second plate.

Description

[Background technology]

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 368,835, filed July 19, 2022, the disclosure of which is incorporated herein by reference.

[0002] This disclosure relates to the field of inductors, particularly gapless inductors. Many inductors, by their construction, are non-tunable and difficult to manufacture, cool, and maintain. They may also require large, inconvenient sizes given the amount of inductance they can provide. The manufacturing techniques used are difficult to automate and can result in quality defects in the core and inductor construction. As a result, the inductors may not be able to operate at medium voltage levels without unacceptable risk or failure. Summary of the Invention

[0003] This patent document describes an apparatus that addresses at least some of the above-mentioned problems and / or other problems.

[0004] In a first aspect, this document discloses a gapless medium-voltage inductor including a magnetic core having an opening extending therethrough, a bobbin having a first plate and a second plate, a spacer disposed within the opening of the magnetic core, a longitudinal path defined through the spacer, the first plate, and the second plate, and a coil extending through the longitudinal path and wound around the core and the bobbin.

[0005] In some embodiments, the core comprises a stack of disks, each having a central opening therethrough. The central openings may together define the opening through the core. The core may have a relative permeability of 5 to 5000. In some embodiments, the inductor may be configured to suppress common mode noise, and the core may have a relative permeability of 5 to 5000.

[0006] In some embodiments, the first and second plates each have an outer dimension greater than the outer dimension of the core. The first and second plates together can extend along less than 50 percent of the longitudinal length of the outer surface of the core. The first and second plates can be configured to form a gap between the coil and the outer edge of the core. The core can be disposed between the first or second plates. A first spacer and at least one of the first or second plates can be integrally formed. The first spacer can electrically insulate the coil from the interior of the core. The first spacer can further include at least one angled edge configured to affect the winding angle of the coil. The angled edge can include a chamfer or a fillet.

[0007] In some embodiments, at least one of the first plate or the second plate includes at least one angled edge configured to affect the winding angle of the coil. The angled edge may be disposed along an inner surface that partially defines the longitudinal path and an outer surface that faces away from the core. Additionally or alternatively, the angled edge may be disposed along an outer surface that is parallel to the longitudinal path and an outer surface that faces away from the core.

[0008] The inductor may further include a second spacer. The first and second spacers may be disposed between the first and second plates and at least partially within the opening in the core. The spacers, the first plate, the second plate, and the core may each be symmetrical about the longitudinal path. The path may extend through at least a portion of the core, may be open on two sides, and may be electrically insulated from the core. In some embodiments, the first plate and the second plate may further include at least one protrusion having an opening configured to receive a fastener.

[0009] In some embodiments, the core can be toroidal in shape. In other embodiments, the core can be racetrack in shape. The core can include a strip wound around the core. The core can include at least one of a cobalt-based nanocrystalline alloy material, a nickel-based nanocrystalline alloy material, an iron-based nanocrystalline alloy material, or an amorphous magnetic material. The core can be configured to have a specific magnetic permeability value. The specific permeability value can be based on a desired application of the inductor. The core can have a variable magnetic permeability throughout its volume. The core can have at least two sections with different magnetic permeabilities. A first section can have a relatively lower magnetic permeability than a second section. The first section can be a lower permeability section on an outer surface of the core, and the second section can be a higher permeability section on an inner surface of the core. The permeability of the first section can be configured to provide short-circuit current protection for the inductor.

[0010] In another aspect, this document discloses an electric device including an inductor. The inductor can include a magnetic core, a bobbin having a first plate and a second plate, and a coil wound around the core and the bobbin. The electric device can further include a housing and a fastener extending through the first plate, the second plate, and at least one side of the housing.

[0011] In some embodiments, the core is secured to the housing by the fastener. The housing can at least partially enclose the core, bobbin, and coil. The housing can include an opening defining an opening through which the inductor passes. The fastener can be made of a dielectric material. The housing can include multiple panels. The multiple panels are held together by the fastener. In some embodiments, the inductor can be potted in a non-insulating resin. In other embodiments, the inductor can be potted in an insulating resin.

[0012] In another aspect, this document discloses a method of constructing an electrical device. The method can include providing a magnetic core, a bobbin, and a wire; disposing the magnetic core within the bobbin; coiling the wire around the bobbin and the magnetic core; disposing a housing around the wound core and bobbin; and securing the housing with fasteners extending through the housing and the bobbin. Providing the magnetic core can include obtaining a nanocomposite magnetic material and tuning the magnetic permeability of the material to a particular level. The tuning can include adjusting at least one of annealing parameters or a material composition of the magnetic core. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a perspective view of an exemplary electrical device. [Figure 2]FIG. 2 is an exploded perspective view of an exemplary electrical device. [Figure 3] FIG. 3 is an exploded perspective view of the exemplary electrical device of FIG. [Figure 4] FIG. 4 is a perspective cross-sectional view of the exemplary electrical device of FIG. [Figure 5] FIG. 5 is a perspective assembly view of the exemplary electrical device of FIG. [Figure 6A] FIG. 6A is a perspective assembly view of an exemplary electrical device. [Figure 6B] FIG. 6B is a perspective assembly view of an exemplary electrical device with a cooling system. [Figure 7] FIG. 7 is a flowchart illustrating an exemplary method for configuring an electrical device. DETAILED DESCRIPTION OF THE INVENTION

[0014] As used herein, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. As used herein, the term "having (or "having") means "including (or "including, but not limited to)." As used herein, the term "exemplary" is intended to mean "by way of example" and is not intended to indicate that any particular exemplary item is preferred or required.

[0015] In this document, when terms such as "first" or "second" are used to modify a noun, their use is intended merely to distinguish one item from another and is not intended to dictate an order unless otherwise specified. The term "about," when used in connection with a numerical value, is intended to include values that are close to, but not exactly, the numerical value. For example, in some embodiments, the term "about" may include values within ±10% of a value.

[0016] In this document, when referring to two physical structures, the term "connected" means that the two physical structures are in contact with each other. Devices that are connected may be fixed to each other or may simply be in contact with each other and not fixed to each other.

[0017] As used herein, terms such as "top" and "bottom," "upper" and "lower," or "front" and "rear" are not intended to have absolute orientations but instead are intended to describe the relative positions of various components with respect to one another. For example, when a device of which the components are a part is oriented in a first direction, a first component may be the "upper" component and a second component may be the "lower" component. When the orientation of a structure containing the components is changed, the relative orientations of the components may be reversed or the components may become coplanar. The claims are intended to encompass all orientations of a device containing such components.

[0018] The present disclosure is not limited to the particular systems, methodologies, or protocols described, and the terminology used herein is for the purpose of describing particular versions or embodiments only, and is not intended to limit the scope.

[0019] In various embodiments, inductors of various designs are provided. The inductors can have a removable housing and an ungapped core. The core can be made of known materials with specific, tunable permeabilities (i.e., permeabilities selected to achieve a desired relationship between inductance and current). Examples are described in more detail below.

[0020] Although the figures detailed below illustrate gapless inductors, the techniques and devices described herein can also be incorporated into gap inductors.

[0021] Common mode inductors, also known as common mode chokes or filters, are electronic components designed to suppress common mode noise. Gapping common mode inductors is a technique used to adjust the inductance and thus the performance of the component by introducing a gap between the magnetic core pieces. The gap may be an air gap or filled with a non-magnetic material.

[0022] Deviations in gap size lead to variations in inductance, which in turn affects the overall performance of the inductor. For common-mode applications, the desired core permeability (expressed as a ratio to the permeability of free space) is between 100 and 5000. Because the desired permeability can be high, the desired gap is often relatively small compared to other inductor variations, which can result in large variations in manufacturing tolerances. Therefore, controlling or eliminating the gap is beneficial in common-mode applications. For various applications, the core permeability is between 5 and 5000.

[0023] FIG. 1 illustrates an example of an electrical device 100 including an inductor 102 within a housing (or enclosure) 108. For illustrative purposes, the housing 108 is depicted as transparent in FIG. 1 . The inductor 102 may include a magnetic core 104 and a wire or coil 106. The coil 106 may be wound around the core. Ends of the coil 106 may form leads 110 extending through the housing 108. The housing 108 may include an opening 112. The opening 112 may function as a passage through the inductor or as an air-cooling vent to an area for receiving a water-cooling unit, as described in more detail below. In some embodiments, the inductor 102 may be configured to suppress common-mode noise. In other words, the inductor 102 may be a common-mode inductor.

[0024] Core 104 is a tape-wound inductor core formed from a thin strip of material (e.g., from tens of microns to about two thousandths of an inch thick). The strip may be wound onto core 104 or a portion of a core (e.g., disks 105A-D). In some embodiments, core 104 may be formed into a stamped and laminated core. The material may be a magnetic material that is iron-based or other nanocrystalline alloy containing one or more of: cobalt (Co), iron-nickel alloy, or iron-cobalt alloy. Thus, the core may be composed of a cobalt-based, nickel-based, or iron-based nanocrystalline alloy material. Other elements, such as boron, carbon, phosphorus, silicon, chromium, tantalum, niobium, vanadium, copper, aluminum, molybdenum, manganese, tungsten, and zirconium, may also be included in core 104. In some embodiments, core 104 may be composed of an amorphous magnetic material. In additional embodiments, core 104 may be composed of a nanocrystalline material. The core 104 may be constructed of a material whose magnetic permeability can be controlled and tuned to a specific value or range of values during construction. For example, known techniques for producing materials with specific magnetic permeabilities, such as strain annealing and electric field annealing, can be employed to fabricate the core 104 material. Cores with specific permeabilities (i.e., a specific ratio of magnetic induction to magnetic strength) can be fabricated by controlling the material composition, as well as the annealing parameters, to produce specific material structures with desired permeabilities. Such materials can be nanocomposites composed of one or more of the elements listed above. Tailoring the permeability facilitates tuning the inductance value of the inductor, allowing for the construction of application-specific inductors. By using multiple concentric core discs, discs with different permeabilities can be used in the same core to achieve the desired permeability profile of the core. The use of single or multiple continuous strip ribbons with varying permeabilities along the ribbon's length can also be utilized to achieve the desired permeability profile of the core.

[0025] The core 104 can be created by processing an amorphous or nanocrystalline magnetic strip (also called a "tape" or "ribbon") and winding it into a desired shape. To form the desired shape, the material can be rapidly solidified, then heat-treated (i.e., heated) in the presence of an applied tensile or magnetic field, and wound around a mandrel to form a tape-wound toroidal-shaped core. The temperature, magnetic field, tensile stress, and ribbon translation speed can all be controlled to affect the resulting core's permeability. In some cases, post-winding treatments, such as transverse or longitudinal field annealing, can also be used. In some embodiments, core disks with distinct permeability variations can be formed and then stacked together to achieve a desired permeability profile in the overall core formed by the stacked disks. Thus, the core 104 can have a variable permeability profile throughout its volume. For example, the core 104 can have at least two regions with different permeabilities. The first region may be a region of lower permeability on the outer surface of the core, and the second region may be a region of relatively higher permeability on the inner surface of the core. In other embodiments, the region of higher permeability may be a region on the outer surface of the core, and the region of lower permeability may be a region on the inner surface of the core. In some embodiments, single or multiple strip ribbon regions with different permeabilities along the length of the ribbon may be utilized to achieve a desired permeability profile across the core formed by the wound ribbon.

[0026] The core 104 has a substantially toroidal shape with an opening extending therethrough. In some embodiments, the core 104 may have other shapes, such as a racetrack, a rectangular shape, an oval or circular cylinder, a cube, etc. The core 104 may also be formed from a combination of components. For example, as shown in FIG. 1 , the core 104 may be a stack of multiple disks 105A-D, each having an opening. The openings in the disks 105A-D are central openings that extend through the center of the disks, such that the openings can be aligned to form an opening through the entire core 104. As another example, the core 104 may be formed from a single or wound ribbon in the form of a tape-wound core, which may have a uniform or alternatively spatially varying magnetic permeability along the length of the ribbon.

[0027] By constructing the core from individual disks 105A-D, the inductance of the core can be varied by adding or removing disks 105A-D. For example, while four disks 105A-D are depicted, an inductor can be constructed with three, five, or any other number of disks. Alternatively, the core 104 can be made from single or multiple strips of ribbon with uniform or spatially varying permeability. The inductance of the core can then be varied by changing the core geometry, as well as the permeability of the strips, the length of the strips, and / or the number of strips comprising the core.

[0028] The disclosed embodiments can provide improved short-circuit current protection compared to conventional inductors. Such short-circuit current protection can be achieved by using a core having a low-permeability region on the outer diameter of the core. The low-permeability region is a region of the core located on the outer diameter of the core that has a relatively lower permeability than other regions or areas of the core. For example, the core 104 can have at least two regions with different permeabilities. A first region can be a relatively low-permeability region on the outer surface of the core, and a second region can be a relatively high-permeability region on the inner surface of the core. The lower-permeability region can be configured to provide short-circuit current protection by providing unused flux capacity to account for current spikes, including short-circuit conditions. In some embodiments, more complex permeability profiles can be utilized to achieve desired flux-link-to-winding current relationships for short-circuit current handling characteristics. In other embodiments, the permeability profiles and saturation levels can be utilized to provide graduated inductance for "soft saturation." Soft saturation occurs when the inductance of an inductor decreases slowly as the current through it increases. Conversely, an inductor that does not exhibit soft saturation (i.e., hard saturation) experiences a sudden drop in inductance at some current level.

[0029] In some embodiments, the low-permeability section has a specific permeability selected to still contribute to rated current operation while taking into account short-circuit current levels. The remainder of the core may also be configured with various sections having permeabilities or permeabilities selected to optimize magnetic flux concentration through the inductor volume. The short-circuit protection may also be applied to inductors with structures other than those specifically described herein. For example, inductors with other core geometries, gapped inductors, etc., may be configured with various permeabilities to optimize magnetic flux concentration for adjusting saturation.

[0030] In one example, the inductor may be a common mode inductor configured to filter common mode noise. In this example, the relative permeability of the core (i.e., the ratio of the permeability of the inductor core to the permeability of free space) may be between 100 and 5000.

[0031] The coil 106 can be magnet wire or other suitable uninsulated wire type. The wire can be various sizes, such as wire having diameters ranging from 40 awg to 4 / 0 awg. In some embodiments, the wire can be a multifilamentary wire containing a combination of wires of the same or different sizes. In such multi-stranded wires, the individual filaments of the wire may not be insulated from each other, but the entire bundle of filaments may be insulated. The coil 106 can be wound around the core 104. Specifically, as shown in FIG. 1, the coil 106 can extend through the opening in the core and wrap around the core in a circular pattern, with each successive wrap extending from the outside through the opening and back out. The number of turns of the wire can depend on the size of the core, the size of the wire, and the desired inductance to be achieved by the inductor.

[0032] Each end of the coil 106 may include a connector. The connector may provide an attachment point for other electrical components in the system. Connectors may take a variety of forms, including bare wire, clamps, ring terminals, spade terminals, fork terminals, male or female blade connectors or quick disconnects, or others. Connectors may be, for example, crimped, soldered, or both soldered and crimped to the ends of the coil 106.

[0033] FIG. 2 is an exploded perspective view of an exemplary electrical device 200. The electrical device 200 may include a housing substantially similar to the housing 108 of FIG. 1, comprised of multiple panels 108A-F. The front panel 108A and the back panel 108B include openings 220. The openings 220 may be openings through the panels 108A, 108B for air cooling of the inductor 102. The openings 220 may define openings through the housing that align with the openings through the inductor 102. Thus, the openings 220 and the openings through the inductor 102 may form a longitudinal path extending through the entire housing inductor, including the bobbin plates 204, 206, and spacers. In some embodiments (as shown in FIG. 2), the openings 220 may include a cross or other shape that separates the opening into multiple smaller openings. In other embodiments (e.g., the openings 112 of FIG. 1), the openings 220 may be circular holes. The opening 220 may also take other open geometric shapes, such as a square, rectangle, triangle, oval, pentagon, hexagon, octagon, etc. The size and location of the opening 220 may be adapted based on the size of the core 102 and bobbin 202, including the size of any interior openings in the core 102 and bobbin 202. For example, the opening 220 may be sized to be approximately the same diameter as the opening through the bobbin 202 and core 102. Although the opening 220 is illustrated as being located approximately in the center of the panel 108A, the opening 220 may be located in other areas of the panel 108A. For example, if the inductor 102 does not include a central passage, the opening 220 may be positioned relative to the outer edge of the inductor 102. For example, by placing multiple openings around the outer edge of the inductor 102, the periphery of the inductor 102 may be cooled.

[0034] The housing may further include a top panel 108C, a bottom panel 108D, and side panels 108E and 108F. As shown, the panels 108A-F may include dovetails (alternating protrusions and grooves) that mate with adjacent panels to form the housing. The panels may be held together by dovetails in combination with fasteners and bobbin clamps. This connection is described in more detail below. The housing may be made of a dielectric material to improve insulation and isolation. For example, housing materials may include non-metallic materials such as glass-reinforced laminates or polymers. In some embodiments, the housing may include a separate insulator within it.

[0035] The inductor 102 may include a core 104 made of a magnetic material wrapped with a coil 106, substantially as described above. The coil 106 may also be wound around a bobbin 202. The bobbin 202 may include a first plate 204 and a second plate 206. The core 104 may be disposed between the first plate 204 and the second plate 206. Thus, as shown in FIG. 4, for example, the first plate 204 and the second plate 206 are disposed at opposite ends of the core 104. Using such a bobbin 202 eliminates the need for an impregnated insert between the core 104 and the coil 106 (e.g., when the inductor is impregnated with epoxy to hold the core and coil in place). Spacers, described in more detail below, also help provide this advantage. The coil 106 may be wound around the core and bobbin at even intervals. In other words, the distance between each wrap of the coil 106 around the core and bobbin may be approximately equal. Thus, the wire of the coil 106 is uniformly distributed around the core and bobbin. The first plate 204 and the second plate 206 are flat and substantially planar. Thus, when the inductor is constructed, the first and second plates 204, 206 can each cover the ends of the core without extending beyond the ends to cover any of the outer sides of the core. As an example, the plates 204, 206 can each extend along less than 10% of the outer sides of the core (longitudinal direction). As another example, the combined coverage of the outer sides of the core by the plates 204, 206 can be less than 25% or less than 50% of the total thickness of the core (longitudinal direction). Stated another way, the combined first and second plates can extend less than 50% of the longitudinal length of the outer surface of the core. The thickness of the first and second plates 204, 206 can vary depending on the particular inductor being constructed.

[0036] The inner surface 205 and outer surface 207 of the first plate 204 and the second plate 206 can include angled edges, such as chamfers or fillets, to affect the winding of the wire of the coil 106 around the bobbin 202. The angled edges can be located along an inner surface (e.g., inner surface 205) that partially defines the longitudinal path and along an outer surface facing away from the core. The angled edges can also be the outer edges between the outer surface 207 of the plates and the outer surface facing away from the core. When wound around the bobbin 202, the coil 106 follows the angle or curve of the angled edges. Thus, the angled edges can allow the wire to bend less than 90 degrees to ensure the integrity and long life of the wire. Additionally, the angled edges can be sized to provide an optimal bend radius for the coil 106 (e.g., to help ensure a smooth wrap around the entire core 104) to help avoid collision of the wire at the inner diameter of the core 104. Furthermore, the pitch of the angled surfaces can be varied based on one or more of the size (e.g., inner and outer diameters) of the bobbin 202, the thickness of the core 104, the size of the coil 106, or the thickness of the spacer 212. The outer diameter of the plates 204, 206 can be larger than the outer diameter of the core 104. For example, if the plates 204, 206 are substantially circular in shape, the outer diameter of the plates 204, 206 can be larger than the outer diameter of the core 104. This difference in outer diameters can provide a gap between the coil 106 and the core 104, isolating the coil 106 from the core 104. Thus, the plates 204, 206 can be configured to form a gap between the coil 106 and the outer edge of the core 104. The configuration of the plates 204, 206 therefore allows for wire guides to be incorporated into the assembly process of the inductor.In some embodiments, the inner diameter of the plates 204, 206 can be smaller than the inner diameter of the core 104 to achieve a similar gap between the inner surface of the core and the coil 106. However, in other embodiments, one or more spacers can be placed within the opening in the core 104 to take up this space and provide insulation between the core 104 and the coil 106, as described below and shown in the figures.

[0037] The electrical device 200 can include one or more spacers 212-218. While four spacers 212-218 are illustrated in FIGS. 2 and 4, more or fewer spacers can be used in some embodiments. For example, the spacers 212-218 can be combined into a single spacer. The spacers 212-218 include openings 220 that align with the openings in the bobbin 202 and core 102. The spacers 212-218 can be positioned within the openings in the core 104. Accordingly, the spacers 212-218 can be hollow cylindrical ("pipe") shaped and sized to have an outer diameter slightly smaller than the inner diameter of the core 104. In other embodiments, for example, where the core 104 is not a toroidal core, the spacers 212-218 can be sized and shaped accordingly. The coil 106 may extend through the center of the spacers 212-218 when wound around the core 104. The spacers 212-218 may thus electrically insulate the coil 106 from the interior of the core 104. Similar to the plates 204, 206 described above, the spacers 212, 218 may include outer angled edges to affect the winding angle of the coil 106. The spacers may be constructed of dielectric and / or insulating materials of appropriate ratings, such as fiberglass, polymer, glass, or other ceramics.

[0038] The bobbin 202 and spacer together insulate the coil 106 from the core 104, ensuring proper function of the inductor. The use of individual spacers 212-218 allows for easy addition or removal of core disks to adjust the inductor. Additionally, the bobbin 202 design allows it to function as an adjustable clamp to hold the core disks together. The bobbin plates 204, 206 slide along fasteners 208, allowing them to expand and contract as core disks are added or removed. In some embodiments, additional nuts can be placed on the fasteners 208 on the outside of each plate 204, 206, but inside the housing to hold the plates 204, 206 in place relative to the fasteners. This allows the inductor 102 to be suspended by the fasteners within the housing. In this way, the bobbin 202 allows for an adjustable inductor that can be used with forced air cooling (due to the longitudinal path through the inductor). The longitudinal path remains constant, even when core disks are added or removed. This suspension system improves the shock resistance and mechanical integrity of the electrical device.

[0039] In some embodiments, one of plates 204, 206 and at least one of spacers 212-218 may be formed as a single piece. For example, spacers 212-218 may be protrusions extending from plate 206. The protrusions may have a central opening therethrough, and the core 104 may be disposed over the protrusions. Plate 204 may then be attached and compressed together with plate 206 as described herein.

[0040] The bobbin 202 and spacers 212-218 can be constructed of a low electrical conductivity material, such as glass reinforced laminates including GPO-3 and FR-4. The material is also preferably machinable for fabrication of the bobbin plates 204, 206 and spacers 212-218. Because the bobbin and spacers contact both the core 104 and coil 106, it is desirable for the material to have low electrical conductivity.

[0041] Referring to FIG. 4, a cross-sectional view of an electrical device 400 illustrating the internal structure of the inductor is shown. As shown, spacers 212-218 can be disposed within the magnetic core 104 having disks 104A-D. The spacers 212-218 and core disks 104A-D can be sandwiched between bobbin plates 204, 206. The coil 206 can then be wound around the bobbin / spacer / core combination. In other embodiments, such as those employing strips (rather than disks) or other core shapes, the spacers 212-218 can be other suitable shapes. Similarly, the strips (or other shapes), like disks, can be sandwiched between the bobbin plates 204, 206 and wound with the coil 206. The coil 106 can pass through the longitudinal path defined through the spacers 212-218 and the plates 204, 206. The wire 402 then wraps around the outside of the plates 204, 206 and returns through the longitudinal path repeatedly. Axis 402 indicates the center of the longitudinal path. The path may extend throughout the electrical device 400, including the opening 220. As mentioned above, this longitudinal path may be used to cool the inductor, for example, by forcing air through the longitudinal path.

[0042] The electrical device 200 also includes one or more fasteners 208. The fasteners 208 may be bolts, screws, threaded rod, pins, rivets, or other suitable hardware for securing the inductor 102, bobbin 202, and housing together. The fasteners 208 may be constructed from a dielectric material (e.g., fiberglass threaded rod or similar material) to prevent electrical interference between the inductor 102 and the fasteners 208. In some embodiments, the fasteners 208 may be secured by nuts 210. The bobbin 202 is shown in FIG. 2 as having approximately four fasteners around its circumference. In other embodiments, more or fewer fasteners may be used. As an example, FIGS. 1 and 3 show an inductor having a bobbin with eight fasteners, four around the periphery of the core and four near the interior, along the main opening of the core. The plates 204, 206 may include one or more protrusions 209. The protrusions 209 may have through openings configured to receive the fasteners 208. The openings through protrusions 209 are substantially parallel to the openings through plates 204, 206 and core 104. In other words, the openings through protrusions 209 are perpendicular to the inner and outer planes of plates 204, 206. This orientation prevents fasteners 208 from interfering with core 104 or coil 106 when the inductor is assembled and installed in the housing.

[0043] The fasteners 208 can extend through both the bobbin plates 204, 206 and at least one of the housing panels 108A or 108B. By extending through both the bobbin 202 and the housing 108, the fasteners 208 can secure the core to the housing and limit movement of the core within the housing. This arrangement can improve the mechanical stability of the inductor and increase its resilience to shocks, drops, or other damage. In some embodiments, the fasteners extend through both the housing panels 108A or 108B. Thus, when the fasteners are secured, they compress the housing panels 108A or 108B together. This compression can also hold other panels 108C-F together (e.g., via dovetail connections) to form a complete housing. Such an arrangement can be seen in FIG. 4, where the fasteners 208A and 208B are depicted as threaded rods with nuts on each end. When the nuts are tightened, they compress the panels 108A or 108B together, holding the inductor 102 and panel 108E between them. Figure 5 is an illustration of the assembled electrical device 200 with the panels 108A-F connected and secured together via fasteners 208. In some embodiments, the fasteners 208 may extend from and be integral with one of the panels 108A, 108B. For example, the fasteners 208 may be integral pins that protrude from the panel 108B.

[0044] FIG. 3 is an exploded view of the exemplary electrical device 100 of FIG. 1. As described above, the bobbin of the electrical device 100 includes eight fasteners 208 arranged around the inner and outer circumferences of the bobbin. The bobbin may include a front plate 304 having inner and outer protrusions 305B and 305A to properly receive each of the fasteners 208. Each of the protrusions 305A-B may include a hole through which the fastener 208 can extend. The front panel 308A of the housing 108 of the electrical device 100 includes eight holes 310 for receiving one of the fasteners 208. The front panel 308A may also include holes corresponding to the wire ends of the coil 106. The coil 106 may extend through the holes in the panel 308A to allow the inductor to be connected to a circuit or other electrical component.

[0045] Some embodiments may include one or more bobbin fastener spacers 302 that fit over the fasteners disposed between the plates 204, 206. The bobbin fastener spacers 302 can provide a specific spacing between the bobbin plates 204, 206 and ensure that the plates 204, 206 maintain this spacing when the fasteners 208 are tightened. Additional spacers can be disposed between the bobbin plates 204, 206 and the housing. These additional spacers can isolate the inductor from the housing. Additionally, the spacers can be shock-absorbing materials to absorb vibrations or other movements of the housing. For example, spacers made of a soft or vibration-damping material can be disposed between the bobbin plates 204, 206 and the housing to limit vibration transmission from the housing to the inductor. This can limit the mechanical stress experienced by the inductor in a particular application. As shown, the housing can at least partially surround the inductor 102, including the core 104, coil 106, and bobbin 202. For example, the only exposed surface may be the surface adjacent the opening 220 along the longitudinal path.

[0046] As shown, each of the above-described embodiments can be employed with a non-potted inductor. However, in some embodiments, the inductor may be potted. Potted inductors are filled with a potting compound to ensure insulation between the coil and core. However, one advantage provided by the disclosed embodiments is that the electrical device can be disassembled (e.g., by first removing fasteners 208) to disassemble the housing and inductor. This facilitates servicing and repair of the inductor. However, if the inductor is potted, the potting compound is not easily removed, potentially making repair difficult, if not impossible.

[0047] FIG. 6A shows an inductor without a separate cooling system installed and is provided for comparison with FIG. 6B, which shows the same inductor with a cooling system 602 installed. The cooling system 602 can be a heat exchanger. The heat exchanger can include a water cooling system with a heat sink disposed in the longitudinal passage through the inductor housing. The cooling system 602 can be connected to the housing by one or more fasteners 208. Additionally or alternatively, other fasteners (e.g., fasteners not used to hold the housing together or fasteners that pass through a bobbin) can be used to connect the cooling system 602 to the electrical device.

[0048] FIG. 7 is a flowchart illustrating an exemplary method 700 for constructing an electrical device. In step 710, method 700 includes providing a magnetic core, a bobbin, and a wire. The core, bobbin, and wire (coil) may be constructed substantially as described above. In step 720, method 700 may further include disposing the magnetic core within the bobbin. For example, the bobbin may include two plates 204, 206 disposed around the core. Thus, disposing the magnetic core within the bobbin may include disposing the plates 204, 206 around the core (e.g., on opposite sides of the core).

[0049] In step 730, method 700 may include winding the wire around the bobbin and the magnetic core, for example, through the central opening of the core and bobbin, as described above. Next, in step 740, method 700 may include placing the housing 108 around the wound core and bobbin. In step 750, method 700 may further include securing the housing with the fasteners 208 extending through the housing 108 and the bobbin (e.g., at least one of bobbin plates 204, 206). In some embodiments, providing a magnetic core includes obtaining a nanocomposite magnetic material and tuning the magnetic permeability of the material to a particular level. The tuning may include tuning at least one of annealing parameters or a material composition of the magnetic core.

[0050] The embodiments described herein can be used in either low-voltage or medium-voltage applications. Unless otherwise specified, the terms "low voltage" and "medium voltage" as used herein are intended to encompass all voltage ranges known in the relevant art. For example, "low voltage" systems typically include electrical systems rated to handle voltages of 1000 volts (V) or less. "Medium voltage" (MV) systems typically include electrical systems rated to handle voltages from about 1000 V to about 38 kilovolts (kV). Some standards define MV to include a voltage range from 600 V to about 69 kV. (Other standards for medium voltage have ranges ranging from 1 kV, 1.5 kV, or 2.4 kV at the lower end to 35 kV, 38 kV, 65 kV, or 69 kV at the upper end.) In such standards, the term "low voltage" would encompass all ranges below these levels (e.g., IEC 60038, ANS / IEEE 1585-200, IEEE Std.).

[0051] The various embodiments disclosed in this patent document, taken individually or in combination, offer advantages over the prior art. For example, a modular design that allows for easy disassembly provides the ability to perform maintenance or repair on the inductor. Additionally, the modular design requires fewer unique parts to manufacture inductors with a variety of inductances and sizes. For example, the same bobbin plate, spacers, fasteners, and housing may be used to manufacture inductors with many different strengths. More specifically, the number of cores can be varied while using the same bobbin plate, fasteners, and housing. To increase or decrease the number of core layers, the number of core spacers and fastener spacers can be varied to increase or decrease the core thickness. Furthermore, the non-gapped design allows for the use of smaller components, improving performance by reducing gap loss, proximity loss, fringe flux, and localized thermal hot spots. The cooling path provided by the longitudinal passage through the inductor enhances cooling and reduces operating temperatures. Placing the cooling path in the center of the inductor allows for cooling the warmest portion of the inductor (unless otherwise designed) to improve convective cooling. The more spaced outer wires naturally cool faster, reducing the need for dedicated cooling paths. If it is desirable to introduce cooling at the outer diameter, the core can be designed to exhibit peak temperatures at the outer surface through optimization through permeability variation, selection of the number and properties of strips, and selection of the number and properties of disks. Other benefits, such as the angled edges of the bobbin or spacer providing controlled wire bend radii, are discussed above.

[0052] Other advantages of the present invention will be apparent to those skilled in the art from the foregoing specification. It will therefore be appreciated by those skilled in the art that changes or modifications may be made to the above-described embodiments without departing from the broad inventive concept thereof. It is therefore to be understood that the invention is not limited to the particular embodiments described herein, but is intended to cover all changes and modifications that are within the scope and spirit of the invention as defined by the appended claims.

[0053] As noted above, this disclosure describes various embodiments of inductors, devices including inductors, and methods for constructing the inductors and devices, including but not limited to those described in the following sections.

[0054] Item 1: A gapless medium-high voltage inductor having a magnetic core having an opening extending therethrough, a bobbin having a first plate and a second plate, a spacer disposed within the opening of the magnetic core, a longitudinal path defined through the spacer, the first plate and the second plate, and a coil extending through the longitudinal path and wound around the core and the bobbin.

[0055] Item 2: The inductor of item 1, wherein a central opening defines the opening through the core.

[0056] Clause 3: The inductor of clause 2, wherein the central opening defines the opening through the core.

[0057] Clause 4: The inductor of clause 1, wherein the inductor is configured to suppress common mode noise.

[0058] Item 5: The inductor according to item 1, wherein the core has a relative permeability of 100 to 5000.

[0059] Item 6: The inductor according to item 1, wherein the first and second plates each have an outer diameter dimension greater than an outer diameter dimension of the core.

[0060] Clause 7: The inductor of clause 1, wherein the first and second plates extend along less than 50 percent of the longitudinal length of the outer surface of the core.

[0061] Clause 8: The inductor of clause 1, wherein the first and second plates are configured to form a gap between the coil and an outer edge of the core.

[0062] Clause 9: The inductor according to clause 1, wherein the core is disposed between the first plate and the second plate.

[0063] Item 10: The inductor according to item 1, wherein the first spacer and at least one of the first plate and the second plate are integrally formed.

[0064] Clause 11: The inductor of clause 1, wherein the first spacer electrically insulates the coil from the interior of the core.

[0065] Item 12: In the inductor described in item 1, the first spacer further comprises: An inductor having at least one angled edge configured to affect a winding angle of the coil.

[0066] Clause 13: The inductor of clause 12, wherein the angled edge comprises a chamfer or a flat edge.

[0067] Clause 14: The inductor of clause 1, wherein at least one of the first plate or the second plate includes at least one angled edge configured to affect a winding angle of the coil.

[0068] Clause 15: The inductor of clause 1, wherein the angled edges are disposed along an inner surface that partially defines the longitudinal path and an outer surface facing away from the core.

[0069] Clause 16: The inductor according to clause 1, wherein the angled edges can be disposed along an outer surface parallel to the longitudinal path and an outer surface facing away from the core.

[0070] Item 17: In the inductor according to item 1, the inductor further comprises: The inductor has a second spacer.

[0071] Clause 18: The inductor of clause 17, wherein the first and second spacers are disposed between the first and second plates and at least partially within the opening in the core.

[0072] Item 19: The inductor of item 17, wherein the spacer, first plate, second plate, and core are each symmetrical about the longitudinal path.

[0073] Clause 20: The inductor of clause 1, wherein the path extends through at least a portion of the core, has two open sides, and is electrically insulated from the core.

[0074] Item 21: In the inductor of item 1, the first and second plates further include: an inductor having at least one protrusion with an opening configured to receive the fastener.

[0075] Item 22: The inductor according to item 1, wherein the core is toroidal in shape.

[0076] Item 23: The inductor according to item 1, wherein the core is racetrack shaped.

[0077] Item 24: The inductor of item 1, wherein the core has a bundle wound around the core.

[0078] Item 25: The inductor of item 1, wherein the core comprises at least one of a cobalt-based nanocrystalline alloy material, a nickel-based nanocrystalline alloy material, an iron-based nanocrystalline alloy material, and an amorphous magnetic material.

[0079] Item 26: The inductor according to item 1, wherein the core is made to have a particular magnetic permeability.

[0080] Item 27: The inductor of item 26, wherein the particular permeability value is based on a desired application of the inductor.

[0081] Item 28: The inductor of item 1, wherein the core has a variable magnetic permeability throughout its volume.

[0082] Item 29: The inductor according to item 28, wherein the core has at least two portions with different magnetic permeabilities.

[0083] Clause 30: The inductor of clause 1, wherein the first portion of the core has a relatively lower magnetic permeability than the second portion of the core.

[0084] Item 31: In the inductor described in item 30, the first portion is a portion of lower magnetic permeability on the area of the core, and the second portion is a portion of relatively higher magnetic permeability on the inner area of the core.

[0085] Item 32: In the inductor described in either item 30 or 31, the magnetic permeability of the first portion can be configured to provide short circuit current protection for the inductor.

[0086] Item 33: An electric device having the inductor according to any one of items 1 to 31.

[0087] Item 34: An electrical device comprising: (a) an inductor having (i) a magnetic core, (ii) a bobbin having a first plate and a second plate, and (iii) a coil wound around the core and the bobbin; (b) a housing; and (c) a fastener extending through the first plate, the second plate, and at least one side of the housing, wherein the housing at least partially encloses the core, the bobbin, and the coil.

[0088] Item 35: The electrical device according to item 34, wherein the core is fixed to the housing by the fastener.

[0089] Item 36: An electrical device according to either item 34 or 35, wherein the housing has an opening defining an opening through which the inductor passes.

[0090] Item 37: The electrical device according to any one of items 34 to 36, wherein the fastener has a dielectric.

[0091] Item 38: The electric device according to any one of items 34 to 37, wherein the housing has a plurality of panels.

[0092] Item 39: The electrical device of item 38, wherein the plurality of panels are held together by the fasteners.

[0093] Item 40: The electric device according to any one of items 34 to 38, wherein the inductor is embedded in a non-insulating resin.

[0094] Item 41: The electric device according to any one of items 34 to 38, wherein the inductor is embedded in an insulating resin.

[0095] Clause 42: A method of constructing an electrical device, the method comprising the steps of: (a) providing a magnetic core, a bobbin, and a wire; (b) placing the magnetic core within the bobbin; (c) winding the wire into a coil around the bobbin and the magnetic core; (d) placing a housing around the wound core and bobbin; and (e) securing the housing with fasteners extending through the housing and the bobbin.

[0096] Item 43: The method of item 42, wherein the step of providing a magnetic core comprises obtaining a nanocomposite magnetic material and tuning the magnetic permeability of the material to a particular level.

[0097] Item 44: The method of item 43, wherein the tuning step comprises adjusting at least one of an annealing parameter or a material composition of the magnetic core.

[0098] Item 45: The inductor according to item 1, wherein the core has a relative permeability of 5 to 5000.

[0099] The above-described features and functions, and alternatives thereof, may be combined into many other different systems or applications. Various alternatives, modifications, variations, or improvements may occur to those skilled in the art, each of which is also intended to be encompassed by the disclosed embodiments.

Claims

1. A gapless medium-high voltage inductor, A magnetic core having an opening that extends through it, A bobbin having a first plate and a second plate, A spacer disposed within the opening of the magnetic core, A longitudinal path defined through the spacer, the first plate and the second plate, A coil extending through the longitudinal path and wound around the core and the bobbin In the gapless medium-high voltage inductor having, The core is positioned between the first plate and the second plate. The core comprises at least one of the following: a cobalt-based nanocrystalline alloy material, a nickel-based nanocrystalline alloy material, an iron-based nanocrystalline alloy material, or an amorphous magnetic material. The spacer has a non-ceramic electrical insulating material, Each of the first plate and the second plate further comprises: Having at least one projection having an opening configured to receive a fastener, Gapless medium-high voltage inductor.

2. In the inductor according to claim 1, The core has a bundle of multiple disks, each having a central opening through which it passes. The central opening defines the opening that penetrates the core, and is an inductor.

3. In the inductor according to claim 1, The first and second plates each have an outer diameter that is larger than the outer diameter of the core. Inductor.

4. An inductor according to claim 3, wherein the first and second plates are configured to form a gap between the coil and the outer edge of the core.

5. An inductor according to claim 1, wherein the inductor is configured to suppress common-mode noise, and the core has a relative permeability of 100 to 5000.

6. An inductor according to claim 1, wherein the first spacer has at least one angled edge configured to electrically insulate the coil from the inside of the core and to affect the winding angle of the coil.

7. In the inductor according to claim 1, At least one of the first plate or the second plate has at least one angled edge configured to affect the winding angle of the coil, An inductor wherein the at least one angled edge is arranged along an inner surface that partially defines the longitudinal path and an outer surface that faces away from the core, or along an outer surface parallel to the longitudinal path and an outer surface that faces away from the core.

8. An inductor according to claim 1, wherein the spacer, the first plate, the second plate, and the core are each symmetrical with respect to the longitudinal path.

9. An inductor according to claim 1, wherein the path extends through at least a portion of the core, has two open sides, and is electrically insulated from the core.

10. In the inductor according to claim 1, the core has a variable permeability through its volume, An inductor wherein the first portion of the core has a magnetic permeability that is relatively lower than that of the second portion of the core.

11. An inductor according to claim 10, wherein the first portion is a portion of the outer surface area of ​​the core with lower magnetic permeability, and the second portion is a portion of the inner surface area of ​​the core with relatively higher magnetic permeability.

12. An inductor according to claim 11, wherein the permeability of the first portion is configured to provide short-circuit current protection to the inductor.

13. An inductor according to claim 1, wherein the core has a relative permeability of 25 to 500.

14. In the inductor according to claim 1, The core has a bundle of multiple disks, each having a central opening through which it passes. The central opening, together with the other, defines the opening that penetrates the core. The core has a variable permeability, An inductor wherein the first portion of the core has a lower relative permeability than the second portion of the core.

15. The inductor according to claim 1, wherein the core has one or more wound strips, and each of the one or more strips has the same material, An inductor wherein the first portion of the core has a lower relative permeability than the second portion of the core.

16. An inductor according to claim 15, wherein at least one of the one or more strips has a permeability that varies along the length of the strip.

17. An inductor according to claim 1, wherein the core has a variable permeability, and the permeability of the core changes so that the inductor exhibits flexible saturation characteristics.

18. An inductor according to claim 1, wherein the core has a variable permeability, and the permeability of the core changes such that the inductor exhibits a strict saturation characteristic.

19. An electrical device, It is an inductor, Magnetic core and A bobbin having a first plate and a second plate, The coils wound around the first and second plates of the core and the bobbin The inductor having, A housing having multiple mating parts, The first plate, the second plate, and fasteners extending through at least one side of the housing It has, The housing at least partially houses the core, bobbin, and coil. Electrical device.

20. An electrical device according to claim 19, wherein the core comprises at least one of a cobalt-based nanocrystalline alloy material, a nickel-based nanocrystalline alloy material, an iron-based nanocrystalline alloy material, or an amorphous magnetic material.

21. An electrical device according to claim 19, wherein the first portion of the core has a magnetic permeability that is relatively lower than that of the second portion of the core.

22. An electrical device according to claim 19, wherein the core has a wound strip.

23. In the electrical device according to claim 22, further, An electrical device having at least one spacer, wherein the core is wound around the at least one spacer, and the coil extends through the at least one spacer.

24. An electrical device according to claim 19, wherein the core has a plurality of stacked core disks.

25. An electrical device according to claim 19, wherein the inductor is at least partially suspended within the housing by the fastener.

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