The field of the embodiments relate generally to power electronics, and more particularly, to integrated inductor assemblies for use in power electronics.
High density power electronic circuits often require the use of multiple magnetic electrical components for a variety of purposes, including energy storage, signal isolation, signal filtering, energy transfer, and power splitting. As the demand for higher power density electrical components increases, it becomes more desirable to integrate two or more magnetic electrical components, such as multiple inductors, into the same core or structure.
However, known integrated magnetic assemblies are often not adequately configured to permit multiple windings to be manufactured on a single structure and to operate independently of one another. As a result, separate cores or structures are used when multiple components are operated independently in a given electronics circuit, thereby increasing the number and size of the components needed for a given operation, and reducing the power density of a given electronics circuit.
In one aspect, an integrated inductor assembly is provided. The integrated inductor assembly includes a magnetic core, a first inductor, and a second inductor. The magnetic core has a first side, an opposing second side, and an opening defined within the magnetic core. The opening extends into the magnetic core from at least one of the first side and the second side. The first inductor includes a first conductive winding inductively coupled to the magnetic core. The first conductive winding includes a first shorting segment positioned within the opening. The second inductor includes a second conductive winding inductively coupled to the magnetic core. The second conductive winding includes a second shorting segment positioned within the opening. The first and second inductors are configurable to operate independently of one another.
In another aspect, a method of assembling an integrated inductor assembly is provided. The method includes providing a magnetic core having a first side, an opposing second side, and an opening defined within the magnetic core, the opening extending into the magnetic core from at least one of the first side and the second side, providing a first conductive winding including a first shorting segment, providing a second conductive winding including a second shorting segment, inductively coupling the first conductive winding to the magnetic core to form a first inductor, the first conductive winding coupled such that the first shorting segment is positioned within the opening, and inductively coupling the second conductive winding to the magnetic core to form a second inductor, the second conductive winding coupled such that the second shorting segment is positioned within the opening, and the first and second conductive windings inductively coupled to the magnetic core such that the first and second inductors are configurable to operate independently of one another.
In yet another aspect, a magnetic core for use in an integrated inductor assembly is provided. The magnetic core includes a first piece defining a first side of the magnetic core, a second piece defining a second side of the magnetic core opposite the first side, and an opening defined within the magnetic core. The second piece is formed separately from and attached to the first piece. At least one of the first piece and the second piece have a plurality of channels defined therein. Each of the channels is configured to receive a conductive winding to form an inductor. The opening extends into the magnetic core from at least one of the first side and the second side. Each of the channels extends into the opening, and is enclosed within the magnetic core between the first piece and the second piece.
Although specific features of various embodiments may be shown in some drawings and not in others, this is for convenience only. Any feature of any drawing may be referenced and/or claimed in combination with any feature of any other drawing.
Exemplary embodiments of integrated inductor assemblies are described herein. An integrated inductor assembly includes a magnetic core, a first inductor, and a second inductor. The magnetic core has a first side, an opposing second side, and an opening defined within the magnetic core. The opening extends into the magnetic core from at least one of the first side and the second side. The first inductor includes a first conductive winding inductively coupled to the magnetic core. The first conductive winding includes a first shorting segment positioned within the opening. The second inductor includes a second conductive winding inductively coupled to the magnetic core. The second conductive winding includes a second shorting segment positioned within the opening. The first and second inductors are configurable to operate independently of one another.
The embodiments described herein provide an integrated inductor assembly that includes at least two inductors capable of operating jointly and independently of one another. The integrated inductor assembly includes a magnetic core having an opening defined therein and a winding assembly inductively coupled to the magnetic core. Inductive segments of the winding assembly are enclosed within the magnetic assembly, and shorting segments that interconnect the inductive segments are positioned within the opening of the magnetic core. Such a configuration reduces and/or minimizes the mutual inductance between multiple inductors formed on the magnetic core, thus enabling the inductors to be operated independently of one another. Further, the integration of multiple inductors on a single magnetic core facilitates reducing the number and size of components needed to construct a given type of electrical circuit (e.g., a power converter).
In the example embodiment, first electrical circuit 108 and second electrical circuit 110 are each buck switching DC-DC voltage converters. Specifically, first electrical circuit 108 includes a first DC voltage supply 114, a first switching device 116, a first diode 118, first inductor 104, a first capacitor 120, a first load 122, and a first controller 124. The positive terminal of first DC voltage supply 114 is coupled to first switching device 116, which is in turn coupled to the cathode end of first diode 118 and first inductor 104. The anode end of first diode 118 is coupled to the return input terminal of first DC voltage supply 114. First capacitor 120 and first load 122 are coupled in parallel, and first inductor 104 is coupled to the first side of the parallel connection between first capacitor 120 and first load 122. First switching device 116 is operated by first controller 124, which switches first switching device 116 between open and closed positions to produce an output voltage Vout of first electrical circuit 108, which is measured as the voltage drop across first load 122.
In the example embodiment, second electrical circuit 110 has an identical architecture to first electrical circuit 108. Specifically, second electrical circuit 110 includes a second DC voltage supply 126, a second switching device 128, a second diode 130, second inductor 106, a second capacitor 132, a second load 134, and a second controller 136. The positive terminal of second DC voltage supply 126 is coupled to second switching device 128, which is in turn coupled to the cathode end of second diode 130 and second inductor 106. The anode end of second diode 130 is coupled to the return input terminal of second DC voltage supply 126. Second capacitor 132 and second load 134 are coupled in parallel, and second inductor 106 is coupled to one side of the parallel connection between second capacitor 132 and second load 134. Second switching device 128 is operated by second controller 136, which switches second switching device 128 between open and closed positions to produce an output voltage Vout of second electrical circuit 110, which is measured as the voltage drop across second load 134.
In the example embodiment, first switching device 116 and second switching device 128 are transistor switches (specifically, MOSFETs), and first controller 124 and second controller 136 are configured to output a pulse-width modulated control signal to the gate side of first switching device 116 and second switching device 128, respectively. In alternative embodiments, first switching device 116 and/or second switching device 128 may be any suitable switching device that enables electronics system 100 to function as described herein. Further, first controller 124 and/or second controller 136 may be configured to supply any suitable control signal to first switching device 116 and second switching device 128, respectively, that enables electronics system 100 to function as described herein.
As described herein in more detail, the construction of integrated inductor assembly 102 enables first inductor 104 and second inductor 106 to operate independently of one another as well as jointly with one another (e.g., as part of the same circuit). Thus, while integrated inductor assembly 102 is described with reference to separate buck switching DC-DC voltage converters (i.e., first electrical circuit 108 and second electrical circuit 110), the embodiments described herein may be implemented in any suitable electrical architecture that enables integrated inductor assembly 102 to function as described herein including, for example, a multi-phase voltage converter in which first inductor 104 is operated out of phase from second inductor 106 by a phase difference of about 90° or 180°.
In the example embodiment, magnetic core 138 has a generally rectangular shape including a first side 148, an opposing second side 150, first and second opposing ends 152 and 154 extending between first side 148 and second side 150, and a front side 156 and an opposing rear side 158 extending between first side 148 and second side 150 and between first end 152 and second end 154. Further, in the example embodiment, magnetic core 138 includes a first piece 160, a second piece 162, a plurality of core bridges 164, and an opening 166 defined within magnetic core 138.
In the example embodiment, first piece 160 defines first side 148 of magnetic core 138 and second piece 162 defines opposing second side 150 of magnetic core 138. Further, first piece 160 and second piece 162 collectively define first end 152, second end 154, front side 156 and rear side 158 of magnetic core 138.
Further, in the example embodiment, first piece 160 includes a plurality of channels 168 defined therein. Channels 168 are configured to receive a portion of conductive windings 140 and 142 to form one of first inductor 104 and second inductor 106. Specifically, channels 168 are defined on an interior surface 170 of first piece 160, and each channel 168 extends from opening 166 towards one of first end 152 and second end 154. Further, in the example embodiment, channels 168 extend around a respective first end 152 or second end 154 to first side 148 of magnetic core 138 such that conductive windings 140 and 142 are flush with a respective first end 152 or second end 154 when integrated inductor assembly 102 is assembled. Further, when integrated inductor assembly 102 is assembled, channels 168 are enclosed within magnetic core 138 between first side 148 and second side 150, more specifically, between first piece 160 and second piece 162.
As shown in
Second piece 162 includes an interior surface 180 facing interior surface 170 of first piece 160 when integrated inductor assembly 102 is assembled. In the example embodiment, interior surface 180 of second piece 162 is substantially planar, and does not include any channels therein. In alternative embodiments, interior surface 180 of second piece 162 may include channels corresponding to channels 168 of first piece 160. In yet further alternative embodiments, interior surface 170 of first piece may be substantially planar (i.e. first piece 160 does not include channels 168), and channels 168 are defined within interior surface 180 of second piece 162.
Referring to
In the example embodiment, opening 166 has a generally rectangular shape, and extends through magnetic core 138 from first side 148 to second side 150. That is, opening 166 extends through both first piece 160 and second piece 162. In alternative embodiments, opening 166 may have any suitable shape that enables integrated inductor assembly 102 to function as described herein. Further, in alternative embodiments, opening 166 can extend into magnetic core 138 from only one of first side 148 or second side 150. That is, opening 166 may not extend completely through magnetic core 138. In some suitable embodiments, opening 166 in magnetic core 138 is filled with one or more non-magnetic materials to prevent foreign objects from entering opening and interfering with the operation of integrated inductor assembly 102.
Core bridges 164 extend between and interconnect first inductive section 182 and second inductive section 184. Further, the plurality of core bridges 164 at least partially define opening 166. In the example embodiment, first piece 160 includes two core bridges 164 disposed on opposite sides of opening 166, and second piece 162 includes two core bridges 164 disposed on opposite sides of opening 166.
In the example embodiment, core bridges 164 are configured to provide a low reluctance magnetic flux path between first inductive section 182 and second inductive section 184 such that first inductor 104 and second inductor 106 can “share” magnetic core 138 when one of first inductive section 182 and second inductive section 184 is not saturated by operation of a respective first inductor 104 or second inductor 106. In the example embodiment, each core bridge 164 is fabricated from a suitable magnetic material, such as ferrite. Further, in the example embodiment, core bridges 164 are integrally formed with one of first piece 160 or second piece 162 of magnetic core 138, although in alternative embodiments, one or more core bridges 164 may be formed separately from first piece 160 and/or second piece 162. The “sharing” of magnetic core 138 between first inductor 104 and second inductor 106 increases the saturation current of first inductor 104 and second inductor 106 (i.e., the current at which magnetic core 138 is saturated) when one of first inductor 104 and second inductor 106 are operated at low loads or low currents because core bridges 164 enable inductors 104 and 106 to utilize portions of magnetic core 138 that would otherwise be unsaturated by operation of one of first inductor 104 or second inductor 106 at low loads or low currents.
As noted above, first inductor 104 includes first conductive winding 140 inductively coupled to magnetic core 138 and second inductor 106 includes second conductive winding 142 inductively coupled to magnetic core 138.
Referring to FIGS. 3 and 8-10, first conductive winding 140 is fabricated from a suitable conductive material (e.g., stamped copper), and includes a first pair 186 of lead segments 188, a first pair 190 of inductive segments 192, and a first shorting segment 194 interconnecting first pair 190 of inductive segments 192.
Inductive segments 192 of first pair 190 of inductive segments 192 are positioned within first pair 172 of channels 168. Each inductive segment 192 of first pair 190 of inductive segments 192 extends from opening 166 towards first end 152 of magnetic core 138 to a corresponding lead segment 188 of first pair 186 of lead segments 188. Inductive segments 192 of first pair 190 of inductive segments 192 are enclosed within magnetic core 138 between first side 148 and second side 150, more specifically, between first piece 160 and second piece 162. Inductive segments 192 of first pair 190 of inductive segments 192 are disposed in a first plane.
First shorting segment 194 is positioned within opening 166, and extends between and interconnects inductive segments 192 of first pair 190 of inductive segments 192. In the example embodiment, first shorting segment 194 is oriented substantially perpendicular to each inductive segment 192 of first pair 190 of inductive segments 192. Further, in the example embodiment, first shorting segment 194 has a substantially planar configuration, and is obliquely angled with respect to the first plane in which first pair 190 of inductive segments 192 is disposed. Specifically, first shorting segment 194 is obliquely angled towards first side 148 of magnetic core 138. Further, in the example embodiment, first shorting segment 194 has a cross-sectional area greater than each inductive segment 192 of first pair 190 of inductive segments 192.
Each lead segment 188 of first pair 186 of lead segments 188 is connected to a respective inductive segment 192 of first pair 190 of inductive segments 192 at first end 152 of magnetic core 138. In the example embodiment, each lead segment 188 of first pair 186 of lead segments 188 extends at an angle of about 90° from a respective inductive segment 192 of first pair 190 of inductive segments 192 towards first side 148 of magnetic core 138. Further, in the example embodiment, each lead segment 188 of first pair 186 of lead segments 188 extends beyond first side 148 of magnetic core 138 such that first pair 186 of lead segments 188 spaces magnetic core 138 from a surface on which integrated inductor assembly 102 is soldered or mounted (e.g., a printed circuit board).
In the example embodiment, second conductive winding 142 has a substantially similar configuration to first conductive winding 140. Specifically, second conductive winding 142 is fabricated from a suitable conductive material (e.g., stamped copper), and includes a second pair 196 of lead segments 188, a second pair 198 of inductive segments 192, and a second shorting segment 200 interconnecting second pair 198 of inductive segments 192.
Inductive segments 192 of second pair 198 of inductive segments 192 are positioned within second pair 174 of channels 168. Each inductive segment 192 of second pair 198 of inductive segments 192 extends from opening 166 towards second end 154 of magnetic core 138 to a corresponding lead segment 188 of second pair 196 of lead segments 188. Inductive segments 192 of second pair 198 of inductive segments 192 are enclosed within magnetic core 138 between first side 148 and second side 150, more specifically, between first piece 160 and second piece 162. Inductive segments 192 of second pair 198 of inductive segments 192 are disposed in a second plane, which, in the example embodiment, is parallel to the first plane in which first pair 190 of inductive segments 192 is disposed. Further, in the example embodiment, the second plane is the same plane as the first plane in which first pair 190 of inductive segments 192 is disposed. As such, first pair 190 of inductive segments 192 and second pair 198 of inductive segments 192 are disposed in substantially the same plane in the example embodiment.
Second shorting segment 200 is positioned within opening 166, and extends between and interconnects inductive segments 192 of second pair 198 of inductive segments 192. In the example embodiment, second shorting segment 200 is oriented substantially perpendicular to each inductive segment 192 of second pair 198 of inductive segments 192. Further, in the example embodiment, second shorting segment 200 has a substantially planar configuration, and is obliquely angled with respect to the second plane in which second pair 198 of inductive segments 192 is disposed. Specifically, second shorting segment 200 is obliquely angled towards second side 150 of magnetic core 138. Further, in the example embodiment, second shorting segment 200 has a cross-sectional area greater than each inductive segment 192 of second pair 198 of inductive segments 192. As shown in
Each lead segment 188 of second pair 196 of lead segments 188 is connected to a respective inductive segment 192 of second pair 198 of inductive segments 192 at second end 154 of magnetic core 138. Thus, first pair 186 of lead segments 188 and second pair 196 of lead segments 188 are disposed on opposite ends of magnetic core 138. In the example embodiment, first pair 186 of lead segments 188 is disposed on first end 152 of magnetic core 138 and second pair of lead segments 188 is disposed on second end 154 of magnetic core 138. Further, in the example embodiment, each lead segment 188 of second pair 196 of lead segments 188 extends at an angle of about 90° from a respective inductive segment 192 of second pair 198 of inductive segments 192 towards second side 150 of magnetic core 138. Further, in the example embodiment, each lead segment 188 of second pair 196 of lead segments 188 extends beyond second side 150 of magnetic core 138 such that second pair 196 of lead segments 188 spaces magnetic core 138 from a surface on which integrated inductor assembly 102 is soldered or mounted (e.g., a printed circuit board).
Referring to
As a result of the configuration of first conductive winding 140 and second conductive winding 142, first inductor 104 and second inductor 106 are essentially single-turn inductors. In other words, first conductive winding 140 and second conductive winding 142 are wound around magnetic core 138 no more than a single turn. As a result, the DC resistances of first inductor 104 and second inductor 106 are reduced as compared to multiple-turn inductors. Further, the inductances of first inductor 104 and second inductor 106 can be comparable to known multiple-turn inductors due to the enclosure of inductive segments 192 within magnetic core 138.
Further, because first shorting segment 194 and second shorting segment 200 are angled away from one another, the first shorting segment 194 and the second shorting segment 200 can overlap one another within opening 166 while still maintaining a sufficient distance from one another to minimize mutual inductance between first inductor 104 and second inductor 106. Such an overlap reduces the overall length 204 (
Various modifications may be made to integrated inductor assembly 102 to further minimize or control the mutual inductance between first inductor 104 and second inductor 106, and/or to tune the performance of integrated inductor assembly 102.
In the embodiments illustrated in
First piece 1604 and second piece 1606 are interconnected to one another by core bridges 164, and third piece 1608 and fourth piece 1610 are interconnected to one another by core bridges 164. Further, first piece 1604 and second piece 1606 collectively define first side 148 of magnetic core 1602, and third piece 1608 and fourth piece 1610 collectively define second side 150 of magnetic core 1602. Further, first piece 1604 and third piece 1608 collectively define first end 152 of magnetic core 1602, and second piece 1606 and fourth piece 1610 collectively define second end 154 of magnetic core 1602. First piece 1604, second piece 1606, third piece 1608 and fourth piece 1610 collectively define front side 156 and rear side 158 of magnetic core 1602.
First pair 172 of channels 168 (shown in
In the embodiment illustrated in
Although integrated inductor assemblies 102, 1300, 1400, 1500, 1600, and 1700 are described as each including two inductors, integrated inductor assemblies 102, 1300, 1400, 1500, 1600, and 1700 can be modified to include more than two inductors, such as three, four, six, or more inductors.
Exemplary embodiments of integrated inductor assemblies are described herein. An integrated inductor assembly includes a magnetic core, a first inductor, and a second inductor. The magnetic core has a first side, an opposing second side, and an opening defined within the magnetic core. The opening extends into the magnetic core from at least one of the first side and the second side. The first inductor includes a first conductive winding inductively coupled to the magnetic core. The first conductive winding includes a first shorting segment positioned within the opening. The second inductor includes a second conductive winding inductively coupled to the magnetic core. The second conductive winding includes a second shorting segment positioned within the opening. The first and second inductors are configurable to operate independently of one another.
As compared to at least some integrated magnetic assemblies, in the integrated inductor assemblies described herein, at least two inductors are formed on a single magnetic core, and the inductors are capable of operating jointly and independently of one another. Inductive segments of the winding assembly are enclosed within the magnetic assembly, and shorting segments that interconnect the inductive segments are positioned within the opening of the magnetic core. Such a configuration provides a compact integrated inductor assembly, yet sufficiently minimizes the mutual inductance between multiple inductors formed on the magnetic core to enable independent operation of the inductors. The compact configuration of integrated inductor assembly also decreases the number of components and board space needed to form a given electrical circuit as compared to the same electrical circuit formed using discrete components. Further, the configuration of integrated inductor assemblies reduces the DC resistance of the inductors formed therein as compared to multiple-turn inductors having similar inductances by utilizing shorter windings to form the inductors, and also by utilizing shorting segments having a greater cross-sectional area than the inductive segments of the winding.
Additionally, the integrated inductor assemblies described herein provide improved performance over discrete inductors when the inductors of the integrated inductor assembly are operated jointly with one another. In particular, when the inductors are operated jointly with one another (e.g., by operating the inductors out of phase from one another by a phase difference of about 180°), the energy losses of the integrated inductor assemblies are reduced as compared to discrete inductors used to perform equivalent functions due to flux cancellation within the magnetic core.
Additionally, the integrated inductor assemblies described herein utilize core bridges to provide a low reluctance flux path between different inductive sections of the magnetic core. The core bridges allow “sharing” of the different inductive sections of the magnetic core when one inductive section is not completely saturated. As a result, the saturation current of the inductors formed on the magnetic core can be increased as compared to discrete inductors.
The order of execution or performance of the operations in the embodiments of the invention illustrated and described herein is not essential, unless otherwise specified. That is, the operations may be performed in any order, unless otherwise specified, and embodiments of the invention may include additional or fewer operations than those disclosed herein. For example, it is contemplated that executing or performing a particular operation before, contemporaneously with, or after another operation is within the scope of aspects of the invention.
Although specific features of various embodiments of the invention may be shown in some drawings and not in others, this is for convenience only. In accordance with the principles of the invention, any feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
This application claims the benefit of U.S. Provisional Patent Application No. 61/782,961 filed Mar. 14, 2013, which is hereby incorporated by reference in its entirety.
Number | Date | Country | |
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61782961 | Mar 2013 | US |