Boost-coupled inductors and switching power converters

Abstract

A switching power converter includes a first switching stage, a second switching stage, a coupling inductor, and a boost winding. The coupling inductor includes a first phase winding, a second phase winding, and a magnetic core. The first phase winding is at least partially wound around a first portion of the magnetic core and is electrically coupled to the first switching stage. The second phase winding is at least partially wound around a second portion of the magnetic core and is electrically coupled to the second switching stage. The boost winding forms at least one turn such that mutual inductance flux associated with each of the first and second phase windings flows through the at least one turn.

Description

Background Technology

[0001] Two or more magnetically coupled inductors are often collectively referred to as "coupled inductors" and have associated mutual inductance and leakage inductance. Mutual inductance is associated with the magnetic coupling between the windings, and the mutual inductance flux is the flux generated by the current flowing through a winding coupled to one or more other windings. Therefore, the greater the mutual inductance, the stronger the magnetic coupling between the windings. On the other hand, leakage inductance is associated with energy storage. Therefore, the greater the leakage inductance, the more energy is stored in the inductor. Leakage inductance is caused by leakage flux, which is the flux generated by the current flowing through a winding of a coupled inductor that is not coupled to any other winding of the coupled inductor. Summary of the Invention

[0002] In a first aspect, a switching power converter includes a first switching stage, a second switching stage, a coupling inductor, and a boost winding. The coupling inductor includes a first phase winding, a second phase winding, and a magnetic core. The first phase winding is at least partially wound around a first portion of the magnetic core and is electrically coupled to the first switching stage. The second phase winding is at least partially wound around a second portion of the magnetic core and is electrically coupled to the second switching stage. The boost winding forms at least one turn such that mutual inductance flux associated with each of the first and second phase windings flows through the at least one turn.

[0003] In an embodiment of the first aspect, the switching power converter further includes a third switching stage. The coupling inductor further includes a third phase winding at least partially wound on a third portion of the magnetic core, wherein the third phase winding is electrically coupled to the third switching stage. The boost winding forms at least one turn such that mutual inductance flux associated with each of the first phase winding, the second phase winding, and the third phase winding flows through the at least one turn.

[0004] In another embodiment of the first aspect, a first portion of the magnetic core includes a first core post of the magnetic core, a second portion of the magnetic core includes a second core post of the magnetic core, and the boost winding is wound on each of the first core post and the second core post.

[0005] In another embodiment of the first aspect, the magnetic core further includes a first guide rail and a second guide rail separated from each other in a first direction, each of the first core post and the second core post being disposed between the first guide rail and the second guide rail in the first direction, and the first core post and the second core post being separated from each other in a second direction orthogonal to the first direction.

[0006] In another embodiment of the first aspect, each of the first phase winding and the second phase winding is at least partially surrounded by the boost winding, as seen when the cross-section of the coupled inductor is viewed in the first direction.

[0007] In another embodiment of the first aspect, the magnetic core further includes one or more leakage elements disposed in the first direction between the first guide rail and the second guide rail, and the one or more leakage elements are disposed in a third direction above the boost winding, the third direction being orthogonal to each of the first direction and the second direction.

[0008] In another embodiment of the first aspect, the first leakage element is attached to the first guide rail, and the first leakage element is separated from the second guide rail by a gap in the first direction.

[0009] In another embodiment of the first aspect, the magnetic core is formed with a passage extending through the magnetic core in a first direction, each of the first phase winding and the second phase winding is wound through the passage, the second phase winding is separated from the first phase winding in the passage in a second direction orthogonal to the first direction, and the boost winding is wound through the passage such that the boost winding is disposed between the first phase winding and the second phase winding in the second direction.

[0010] In another embodiment of the first aspect, (1) the passage has a height in a third direction, wherein the third direction is orthogonal to each of the first direction and the second direction; (2) the passage has a width in the second direction; and (3) the height of the passage varies along the width of the passage such that the height of the passage at the boost winding is less than the height of the passage at each of the first phase winding and the second phase winding.

[0011] In another embodiment of the first aspect, the switching power converter may further include a controller configured to control the switches of at least the first switching stage and the second switching stage.

[0012] In a second aspect, a switching power converter includes a first boost-coupled inductor and a second boost-coupled inductor. The first boost-coupled inductor includes M phase windings and a first boost winding, wherein the first boost winding forms at least one first turn such that mutual inductance flux associated with each of the M phase windings flows through the at least one first turn, and M is an integer greater than one. The second boost-coupled inductor includes N phase windings and a second boost winding, wherein the second boost winding forms at least one second turn such that mutual inductance flux associated with each of the N phase windings flows through the at least one second turn, and N is an integer greater than one. The switching power converter further includes a corresponding switching stage electrically coupled to each of the M phase windings and a corresponding switching stage electrically coupled to each of the N phase windings. The first boost winding and the second boost winding are series-coupled.

[0013] In an embodiment of this second aspect, N equals M.

[0014] In another embodiment of this second aspect, N is different from M.

[0015] In another embodiment of the second aspect, the switching power converter further includes a controller configured to control the switching of at least two of the following: (1) each switching stage electrically coupled to each of the M phase windings; and (2) each switching stage electrically coupled to each of the N phase windings.

[0016] In a third aspect, a boost-coupled inductor includes: (a) a magnetic core comprising a plurality of cores; (b) a corresponding phase winding wound at least partially on each of the plurality of cores; and (c) a boost winding wound at least partially on each of the plurality of cores.

[0017] In another embodiment of the third aspect, (1) the magnetic core further includes a first guide rail and a second guide rail separated from each other in a first direction; (2) each of the plurality of core posts is disposed between the first guide rail and the second guide rail in the first direction; and (3) the plurality of core posts are separated from each other in a second direction orthogonal to the first direction.

[0018] In another embodiment of this third aspect, each phase winding is at least partially surrounded by the boost winding, as seen when the cross-section of the coupled inductor is viewed in the first direction.

[0019] In another embodiment of this third aspect, the boost winding is disposed alongside the respective phase windings wound on the plurality of core posts.

[0020] In another embodiment of the third aspect, the magnetic core further includes one or more leakage elements disposed in the first direction between the first guide rail and the second guide rail, and the one or more leakage elements are disposed in a third direction above the boost winding, wherein the third direction is orthogonal to each of the first direction and the second direction.

[0021] In another embodiment of the third aspect, the first leakage element is attached to the first guide rail, and the first leakage element is separated from the second guide rail by a gap in the first direction.

[0022] In a fourth aspect, a boost-coupled inductor includes: (1) a coupled inductor including a first phase winding and a second phase winding; (2) a magnetic core; and (3) a boost winding. The magnetic core forms a passage extending through the magnetic core in a first direction, and the first phase winding and the second phase winding are wound through the passage. The second phase winding is separated from the first phase winding in the passage in a second direction orthogonal to the first direction. The boost winding is wound through the passage such that the boost winding is disposed between the first phase winding and the second phase winding in the second direction.

[0023] In an embodiment of the third aspect, the passage has a height in a third direction, wherein the third direction is orthogonal to each of the first direction and the second direction; the passage has a width in the second direction; and the height of the passage varies along the width of the passage such that the height of the passage at the boost winding is less than the height of the passage at each of the first phase winding and the second phase winding. Attached Figure Description

[0024] Figure 1 This is a perspective view of a boost-coupled inductor according to an embodiment.

[0025] Figure 2 yes Figure 1 A top view of a boost-coupled inductor.

[0026] Figure 3 yes Figure 1 Front elevation view of the boost coupling inductor.

[0027] Figure 4 yes Figure 1 Left elevation view of the boost coupling inductor.

[0028] Figure 5 yes Figure 1 The right elevation view of the boost coupling inductor.

[0029] Figure 6 yes Figure 1 The boost coupling inductor along Figure 2 The cross-sectional view taken from line 6A-6A.

[0030] Figure 7 yes Figure 1 The boost coupling inductor along Figure 3 The cross-sectional view taken from line 7A-7A.

[0031] Figure 8 yes Figure 1 A perspective view of the phase windings of a boost-coupled inductor.

[0032] Figure 9 yes Figure 1Another perspective view of the phase winding of the boost-coupled inductor.

[0033] Figure 10 yes Figure 1 A perspective view of an alternative embodiment of the phase winding of a boost-coupled inductor.

[0034] Figure 11 yes Figure 1 A perspective view of the boost winding of a boost-coupled inductor.

[0035] Figure 12 yes Figure 1 Another perspective view of the boost winding of the boost-coupled inductor.

[0036] Figure 13 yes Figure 1 A perspective view of an alternative embodiment of the boost winding of a boost-coupled inductor.

[0037] Figure 14 yes Figure 1 A cross-sectional view of a boost-coupled inductor, labeled to symbolically show several mutual inductance flux paths and one leakage flux path.

[0038] Figure 15 yes Figure 1 The left elevation view of the boost coupling inductor, which is labeled symbolically to show... Figure 14 Another view of the leakage flux path shown in the figure.

[0039] Figure 16 This is a perspective view of another boost-coupled inductor according to an embodiment.

[0040] Figure 17 yes Figure 16 Front elevation view of the boost coupling inductor.

[0041] Figure 18 yes Figure 16 A top view of a boost-coupled inductor.

[0042] Figure 19 yes Figure 16 Left elevation view of the boost coupling inductor.

[0043] Figure 20 yes Figure 16 The right elevation view of the boost coupling inductor.

[0044] Figure 21 yes Figure 16 The boost coupling inductor along Figure 17 The cross-sectional view taken from line 21A-21A.

[0045] Figure 22 yes Figure 16 The boost coupling inductor along Figure 18 The cross-sectional view taken from line 22A-22A.

[0046] Figure 23 yes Figure 16 A perspective view of the phase windings of a boost-coupled inductor.

[0047] Figure 24 yes Figure 16 A perspective view of the boost winding of a boost-coupled inductor.

[0048] Figure 25 yes Figure 16 A perspective view of an alternative embodiment of the boost winding of a boost-coupled inductor.

[0049] Figure 26 This is a perspective view of another boost-coupled inductor according to an embodiment.

[0050] Figure 27 It is a component that omits the magnetic core. Figure 26 A perspective view of a boost-coupled inductor.

[0051] Figure 28 yes Figure 1 A perspective view of the phase winding of an alternative embodiment of a boost-coupled inductor.

[0052] Figure 29 yes Figure 28 A top view of a boost-coupled inductor.

[0053] Figure 30 yes Figure 28 Front elevation view of the boost coupling inductor.

[0054] Figure 31 yes Figure 28 Left elevation view of the boost coupling inductor.

[0055] Figure 32 yes Figure 28 The right elevation view of the boost coupling inductor.

[0056] Figure 33 yes Figure 28 The boost coupling inductor along Figure 29 The cross-sectional view taken from line 33A-33A.

[0057] Figure 34 yes Figure 28 The boost coupling inductor along Figure 30 The cross-sectional view taken from line 34A-34A.

[0058] Figure 35 yes Figure 28A perspective view of the phase windings of a boost-coupled inductor.

[0059] Figure 36 yes Figure 28 A perspective view of the boost winding of a boost-coupled inductor.

[0060] Figure 37 yes Figure 1 A cross-sectional view of another alternative embodiment of the boost-coupled inductor.

[0061] Figure 38 yes Figure 1 A cross-sectional view of another alternative embodiment of the boost-coupled inductor.

[0062] Figure 39 This is a schematic diagram of a switching power converter including a boost coupling inductor according to an embodiment.

[0063] Figure 40 This is a schematic diagram of a switching power converter including multiple boost-coupled inductors according to an embodiment. Detailed Implementation

[0064] This document discloses boost-coupled inductors and associated systems and methods. For example, some embodiments include a coupled inductor having two or more phase windings and a boost winding to collectively form a boost-coupled inductor. The boost winding is magnetically coupled to each phase winding. In some embodiments, the boost winding forms at least one turn such that the mutual inductance flux associated with each phase winding flows through the turn of the boost winding, which also advantageously promotes strong coupling of leakage flux to the boost winding. As discussed below, these boost-coupled inductors can provide significant advantages, such as in power converter applications. Additionally, as also discussed below, some embodiments of the boost-coupled inductor are configured to facilitate ease of manufacture and low cost.

[0065] Figure 1 This is a perspective view of a boost-coupled inductor 100, which is an embodiment of a novel boost-coupled inductor. Figure 2 This is a top view of the boost coupling inductor 100. Figure 3 This is a front elevation view of the boost coupling inductor 100. Figure 4 This is a left elevation view of the boost coupling inductor 100, and Figure 5 This is the right elevation view of the boost coupling inductor 100. Figure 6 It is the boost coupling inductor 100 along Figure 2 The cross-sectional view taken from line 6A-6A, and Figure 7 It is the boost coupling inductor 100 along Figure 3A cross-sectional view taken from lines 7A-7A. The boost-coupled inductor 100 includes a magnetic core 102, multiple phase windings 104, and a boost winding 106. In this document, specific instances of items (e.g., phase winding 104(1)) may be referred to by numbers in parentheses, while numbers without parentheses refer to any such item (e.g., phase winding 104).

[0066] The magnetic core 102 is formed, for example, from a ferrite magnetic material. The magnetic core 102 includes a first guide rail 108, a second guide rail 110, a plurality of core posts 112, and a leakage element 114. Although the magnetic core 102 is shown as including four core posts 112, the magnetic core 102 can be modified to have any number of core posts 112, as long as the magnetic core 102 has at least two core posts 112. Furthermore, although the figure includes dashed lines separating the leakage element 114 from the first guide rail 108 to aid the observer in distinguishing these elements, there does not need to be an interruption between the first guide rail 108 and the leakage element 114. The configuration of the leakage element 114 can be modified without departing from the scope of the invention. For example, the leakage element 114 can be replaced by two leakage elements disposed at opposite ends of the magnetic core 102, wherein each of these two leakage elements is disposed in direction 116 between the first guide rail 108 and the second guide rail 110. As another example, the leakage element 114 can be replaced by a plurality of leakage elements disposed between the core posts 112 in the direction 118.

[0067] The first guide rail 108 and the second guide rail 110 are separated from each other in direction 116 (see...). Figure 2 , Figure 4 , Figure 5 and Figure 7 Furthermore, the core post 112 is positioned in direction 116 between the first guide rail 108 and the second guide rail 110 (see...). Figure 6 and Figure 7The core posts 112 are separated from each other in direction 118, which is orthogonal to direction 116. In some embodiments, the core posts 112 engage with the first rail 108 and the second rail 110 in direction 116, and in some other embodiments, the core posts 112 are separated from the first rail 108 and / or the second rail 110 by corresponding gaps (not shown), thereby helping to prevent saturation of the core 102. A leakage element 114 is also disposed in direction 116 between the first rail 108 and the second rail 110, such that the leakage element 114 is disposed in direction 120 above the boost winding 106, which is orthogonal to each of directions 116 and 118. In some embodiments, the leakage element 114 is attached to the first rail 108, and the leakage element 114 is separated from the second rail 110 in direction 116 by a gap 122. The gap 122 may include, for example, air, plastic, paper, adhesive, or a magnetic material with a lower permeability than the magnetic core 102.

[0068] The corresponding phase winding 104 is at least partially wound on each core post 112, and the boost winding 106 is at least partially wound on all core posts 112. Thus, each phase winding 104 is at least partially surrounded by the boost winding 106, as seen when the cross-section of the boost coupled inductor 100 is viewed in direction 116 (see, for example...). Figure 6 Therefore, the boost winding 106 is advantageously strongly magnetically coupled to each phase winding 104. The boost winding 106 is electrically isolated from the phase windings 104. For example, in some embodiments, the phase windings 104 and / or the boost winding 106 are coated with a dielectric material (not shown). As another example, in some embodiments, the boost winding 106 is physically separated from the phase windings 104.

[0069] Figure 8 and Figure 9 These are different perspective views of an instance of phase winding 104, namely, Figure 9 It shows relative to Figure 8 The view is rotated 180 degrees by the phase winding 104. Each phase winding 104 has opposing tabs 124 and 126 formed at the respective ends of the winding, as shown. Figure 8 and Figure 9 The phase windings 104 are shown separately. The configuration of the phase windings 104 can be changed without departing from the scope of the invention. For example, the phase windings 104 can be modified to have different solder pads or even to have no solder pads. As another example, the phase windings 104 can be modified to form additional turns. As yet another example, Figure 10 This is a perspective view of phase winding 1004, an alternative embodiment of phase winding 104. Phase winding 1004 has opposing solder pads 1024 and 1026 formed at corresponding ends of the winding. Figure 10This configuration can be particularly advantageous in applications where the mounting pads of the printed circuit board (PCB) corresponding to pads 1024 and 1026 are aligned in direction 1016.

[0070] Figure 11 and Figure 12 These are different perspective views of the boost winding 106. The boost winding 106 forms opposing solder tabs 128 and 130, as shown in... Figure 11 and Figure 12 The configuration of the boost winding 106 can be changed without departing from the scope of the invention. For example, the boost winding 106 can be modified to have different solder pads or even no solder pads. As another example, the boost winding 106 can be modified to form additional turns. As yet another example, Figure 13 This is a perspective view of a boost winding 1306, an alternative embodiment of the boost winding 106. The boost winding 1306 forms opposing tabs 1328 and 1330. The boost winding 1306 has a higher DC resistance (DCR) than the boost winding 106, but in applications where the boost winding carries a relatively small current amplitude (e.g., a small alternating current (AC)) in the boost-coupled inductor 100, the higher resistance may be acceptable.

[0071] Figure 14 It is similar to Figure 6 A cross-sectional view is shown, labeled to symbolically illustrate several mutual inductance flux paths in the boost coupled inductor 100. Lines 1402, 1404, and 1406 represent the mutual inductance flux flowing from phase winding 104(1) to phase windings 104(2), 104(3), and 104(4), respectively. Although not shown, additional mutual inductance flux paths exist between instances of other phase windings 104. Although the mutual inductance flux from each phase winding 104 flows through the turns of the boost winding 106, in some applications the net mutual inductance flux flowing through the phase windings 104 may be zero. For example, the mutual inductance flux from some phase windings 104 may cancel out the mutual inductance flux from other phase windings 104 in the boost winding 106, so that the boost winding 106 “sees” zero mutual inductance flux.

[0072] Figure 14 It also includes a line 1408 representing the leakage flux associated with phase winding 104(1). Figure 15 It is similar to Figure 4 The left elevation view, which is labeled to show Figure 14 Another view of the leakage flux path. From Figure 14 and Figure 15It is evident that the leakage flux associated with phase winding 104(1) flows through the first rail 108, the leakage element 114, and the second rail 110, and then returns to phase winding 104(1). Therefore, this leakage flux flows through the turns of boost winding 106. The leakage flux associated with other instances of phase winding 104 also flows through the turns of boost winding 106 along a similar path. Thus, boost winding 106 is strongly magnetically coupled to the leakage flux associated with phase winding 104, thereby promoting the high performance of boost-coupled inductor 100. The fact that boost winding 106 is within the mutual inductance flux path helps to maximize the leakage flux coupled to boost winding 106 by reducing the likelihood of leakage flux escaping from core 102 before coupling to boost winding 106.

[0073] Additionally, it should be noted that the instance of a single boost winding (i.e., boost winding 106) being magnetically coupled to all phase windings 104 eliminates the need for additional windings to be magnetically coupled to the phase windings 104. This use of a single boost winding for magnetic coupling to all phase windings 104 contributes to the low cost and ease of manufacture of the boost-coupled inductor 100. Furthermore, the configuration of the boost-coupled inductor 100 facilitates PCB layout in switching power converter applications, such as by placing each switching stage electrically coupled to the respective phase winding 104 on the common side of the boost-coupled inductor 100, and by eliminating the need to connect multiple instances of boost windings. Furthermore, the fact that each phase winding 104, as discussed above, is at least partially surrounded by the boost winding 106 promotes the electromagnetic compatibility of the boost-coupled inductor 100 with other circuit systems, because the boost winding 106 potentially prevents noise associated with the switching current flowing through the phase winding 104 from radiating from the boost-coupled inductor 100.

[0074] Figure 16 This is a perspective view of a boost-coupled inductor 1600, which is another embodiment of a novel boost-coupled inductor. Figure 17 This is a front elevation view of the 1600 boost-coupled inductor. Figure 18 This is a top view of the 1600 boost-coupled inductor. Figure 19 This is the left elevation view of the boost coupling inductor 1600, and Figure 20 This is the right elevation view of the boost coupling inductor 1600. Figure 21 It is the boost coupling inductor 1600 along Figure 17 The cross-sectional view taken from line 21A-21A, and Figure 22 It is the boost coupling inductor 1600 along Figure 18 The cross-sectional view taken from lines 22A-22A. The boost coupled inductor 1600 includes a magnetic core 1602, multiple phase windings 1604, and a boost winding 1606.

[0075] The magnetic core 1602 is formed, for example, of a ferrite magnetic material. The magnetic core 1602 includes a first guide rail 1608, a second guide rail 1610, a plurality of core posts 1612, and a leakage element 1614. Although the magnetic core 1602 is shown as including three core posts 1612, the magnetic core 1602 can be modified to have any number of core posts 1612, as long as the magnetic core 1602 has at least two core posts 1612. The first guide rail 1608 and the second guide rail 1610 are separated from each other in direction 1616, and the core posts 1612 are disposed between the first guide rail 1608 and the second guide rail 1610 in direction 1616. The core posts 1612 are separated from each other in direction 1618, wherein direction 1618 is orthogonal to direction 1616. In some embodiments, the core 1612 engages with the first rail 1608 and the second rail 1610 in direction 1616, and in some other embodiments, the core 1612 is separated from the first rail 1608 and / or the second rail 1610 by a corresponding gap (not shown), thereby helping to prevent saturation of the core 1602. A leakage element 1614 is also disposed in direction 1616 between the first rail 1608 and the second rail 1610, such that the leakage element 1614 is disposed in direction 1620 above the boost winding 1606, wherein direction 1620 is orthogonal to each of directions 1616 and 1618. In some embodiments, the leakage element 1614 is attached to the first rail 1608, and the leakage element 1614 is separated from the second rail 1610 in direction 1616 by a gap 1622. The gap 1622 comprises, for example, air, plastic, paper, adhesive, or a magnetic material with a lower permeability than the core 1602.

[0076] The corresponding phase winding 1604 is at least partially wound around each core post 1612. Thus, each phase winding 1604 is at least partially surrounded by a boost winding 1606, as seen when the cross-section of the boost-coupled inductor 1600 is viewed in direction 1620 (see, for example...). Figure 21 and Figure 22 Therefore, the boost winding 1606 is strongly magnetically coupled to each phase winding 1604. Furthermore, the mutual inductance flux and leakage flux generated by the current flowing through the phase windings 1604 flow through the turns formed by the boost winding 1606 in a manner similar to that discussed above with respect to the boost-coupled inductor 100. In addition, the boost-coupled inductor 1600 achieves the advantages discussed above with respect to the boost-coupled inductor 100. Figure 23This is a perspective view of an example of phase winding 1604. Each phase winding 1604 has tabs 1624 and 1626 formed at opposite winding ends. The configuration of the phase windings 1604 can be changed without departing from the scope of the invention. For example, the phase windings 1604 can be modified to have different tabs or even no tabs. As another example, the phase windings 1604 can be modified to form additional turns.

[0077] Figure 24 This is a perspective view of the boost winding 1606. The boost winding 1606 forms opposing tabs 1628 and 1630. The configuration of the boost winding 1606 can be changed without departing from the scope of the invention. For example, the boost winding 1606 can be modified to have different tabs or even no tabs. As another example, the boost winding 1606 can be modified to form additional turns. As yet another example, Figure 25 This is a perspective view of a boost winding 2506, an alternative embodiment of the boost winding 1606. The boost winding 2506 is not as tall as the boost winding 1606 in direction 1616, which can be advantageous in height-constrained applications.

[0078] Figure 26 This is a perspective view of a boost-coupled inductor 2600, which is another embodiment of a novel boost-coupled inductor. The boost-coupled inductor 2600 includes a magnetic core 2602, a first phase winding 2604, a second phase winding 2606, and a boost winding 2608.

[0079] The magnetic core 2602 is formed, for example, from a ferrite magnetic material. The magnetic core 2602 includes a first element 2610 and a second element 2612 stacked in direction 2614. Figure 27 This is a perspective view of the boost-coupled inductor 2600 with the second element 2612 removed to show the interior of the boost-coupled inductor 2600. A magnetic core 2602 is formed with a passage 2616 extending through it in direction 2618, where direction 2618 is orthogonal to direction 2614. The passage 2616 has a width 2620 in direction 2622, where direction 2622 is orthogonal to each of directions 2614 and 2618. Without departing from the scope of this document, the magnetic core 2602 may be formed from a single element, or the magnetic core 2602 may be formed from three of more elements.

[0080] Each of the first phase winding 2604, the second phase winding 2606, and the boost winding 2608 is wound through the passage 2616. The second phase winding 2606 is separated from the first phase winding 2604 in direction 2622, and the boost winding 2608 is disposed between the first phase winding 2604 and the second phase winding 2606 in direction 2622. In some embodiments, each of the first phase winding 2604, the second phase winding 2606, and the boost winding 2608 is a U-shaped winding. The passage 2616 has a height 2624 in direction 2614. In some embodiments, the height 2624 varies along the width 2620. For example, in some embodiments, the height 2624 of the boost winding 2608 is smaller than the height 2624 of each of the first phase winding 2604 and the second phase winding 2606 to achieve the required leakage inductance value.

[0081] Figure 28 Is as Figure 1 A perspective view of a boost-coupled inductor 2800, an alternative embodiment of the boost-coupled inductor 100. Figure 29 This is a top view of the 2800 boost-coupled inductor. Figure 30 This is a front elevation view of the 2800 boost coupling inductor. Figure 31 This is the left elevation view of the boost coupling inductor 2800, and Figure 32 This is the right elevation view of the 2800 boost coupling inductor. Figure 33 It is the boost coupling inductor 2800 along Figure 29 The cross-sectional view taken from line 33A-33A, and Figure 34 It is the boost coupling inductor 2800 along Figure 30 The cross-sectional view taken from line 34A-34A. The difference between boost-coupled inductor 2800 and boost-coupled inductor 100 is that: (1) boost-coupled inductor includes a magnetic core 2802 in place of magnetic core 102; (2) boost-coupled inductor 2800 includes multiple phase windings 2804 in place of multiple phase windings 104; and (3) boost-coupled inductor 2800 includes a boost winding 2806 in place of boost winding 106.

[0082] Figure 28 Magnetic core 2802 and Figure 1The difference in magnetic core 102 is that core 2802 includes two leakage elements 2814 and 2814' instead of a single leakage element 114. Each of leakage elements 2814 and 2814' is positioned in direction 116 between rails 108 and 110, and a gap 2822 exists between the two leakage elements in direction 116. Gap 2822 may include, for example, air, plastic, paper, adhesive, or a magnetic material with a lower permeability than core 2802. Leakage element 2814 is engaged with the first rail 108, and leakage element 2814' is engaged with the second rail 110. These figures include dashed lines that separate leakage elements 2814 and 2814' from rails 108 and 110, respectively, to help the observer distinguish the leakage elements from the rails. However, there need to be no interruption between these rails and leakage elements.

[0083] Each phase winding 2804 is similar to Figure 10 Phase winding 1004. Figure 35 This is a perspective view of an example of phase winding 2804. Each phase winding 2804 has opposing tabs 3524 and 3526 formed at the respective ends of the winding. A boost winding 2806 is wound at least partially around all the core posts 112. However, unlike the boost winding 106 of the boost coupled inductor 100, the boost winding 2806 is not wound on the turns of the phase winding 2804 in direction 120. Instead, the boost winding 2806 is positioned next to the phase winding 2804 in direction 116, that is, the boost winding 2806 is located between the turns of the phase winding 2804 and the second rail 110 in direction 116. Nevertheless, the boost winding 2806 is within the same flux path as the boost winding 106, and therefore, from an inductive point of view, the boost winding 2806 is electrically equivalent to the boost winding 106. The boost winding 2806 can alternatively be arranged in the direction 116 between the first guide rail 108 and the turns of the phase winding 2804.

[0084] Figure 36 This is a perspective view of the boost winding 2806. For example, the boost winding 2806 can be modified to have solder tabs or through-hole pins formed at its opposite ends.

[0085] Figure 37 Is as Figure 1 A cross-sectional view of a boost-coupled inductor 3700, an alternative embodiment of the boost-coupled inductor 100. The boost-coupled inductor 3700... Figure 37 The cross-sectional view is similar to that of boost-coupled inductor 100. Figure 6A cross-sectional view. The difference between boost-coupled inductor 3700 and boost-coupled inductor 100 is that boost-coupled inductor 3700 includes a boost winding 3706 instead of boost winding 106. Boost winding 3706 is similar to boost winding 106, except that boost winding 3706 is wound around three sides of each core post 112, such as... Figure 37 As shown, the boost winding 3706 has essentially the same inductance characteristics as the boost winding 106.

[0086] Figure 38 Is as Figure 1 A cross-sectional view of a boost-coupled inductor 3800, an alternative embodiment of the boost-coupled inductor 100. The boost-coupled inductor 3800... Figure 38 The cross-sectional view is similar to that of boost-coupled inductor 100. Figure 6 A cross-sectional view. The difference between boost-coupled inductor 3800 and boost-coupled inductor 100 is that boost-coupled inductor 3800 includes a boost winding 3806 replacing boost winding 106. Boost winding 3808 is similar to boost winding 106, except that boost winding 3806 substantially surrounds the entire cross-sectional area of ​​the second guide rail 110, as seen when the cross-section of boost-coupled inductor 3800 is viewed in direction 116 (observation). Figure 38 (See the page). The boost winding 3808 has essentially the same inductance characteristics as the boost winding 106.

[0087] One possible application of the boost-coupled inductor disclosed in this article is in switching power supply converters. For example, Figure 39 and Figure 40 This paper demonstrates possible switching power converter applications for the boost-coupled inductor disclosed herein. However, it is to be understood that the boost-coupled inductor disclosed herein is not limited to these applications.

[0088] Figure 39This is a schematic diagram of a switching power converter 3900, which includes a boost-coupled inductor 3902, multiple switching stages 3904, a tuning inductor 3906, and a controller 3908. The boost-coupled inductor 3902 includes M phase windings 3910, a boost winding 3912, and a magnetic core 3914, where M is an integer greater than one. The boost-coupled inductor 3902 is, for example, one of the boost-coupled inductors discussed above. For example, in one embodiment, the boost-coupled inductor 3902 is an embodiment of the boost-coupled inductor 100, wherein the phase windings 3910 are phase windings 104, the boost windings 3912 are boost windings 106, and the magnetic core 3914 is the magnetic core 102. As another example, in another embodiment, boost-coupled inductor 3902 is an embodiment of boost-coupled inductor 1600, wherein phase winding 3910 is phase winding 1604, boost winding 3912 is boost winding 1606, and core 3914 is core 1602. As yet another example, in another embodiment, M equals 2, boost-coupled inductor 3902 is an embodiment of boost-coupled inductor 2600, wherein phase winding 3910 is phase windings 2604 and 2606, boost winding 3912 is boost winding 2608, and core 3914 is core 2602.

[0089] Each phase winding 3910 is electrically coupled to a corresponding switching stage 3904 at the switching node VX. Each switching stage 3904 includes a corresponding first switching device 3916 and a corresponding second switching device 3918 electrically coupled to the switching node VX, but for clarity, only... Figure 39An example of each of the switching devices 3916 and 3918 is marked. The first switching device 3916 and the second switching device 3918 are, for example, transistors, such as field-effect transistors (FETs) or bipolar junction transistors (BJTs). Alternatively, the first switching device 3916 or the second switching device 3918 may be replaced by a corresponding diode. Each first switching device 3916 is controlled by a corresponding control signal Φ generated by the controller 3908, and each second switching device 3918 is controlled by a corresponding control signal Φ' generated by the controller 3908. In some embodiments, the controller 3908 is configured to generate control signals Φ and Φ' to control the switching of the switching stage 3904, thereby regulating one or more parameters of the switching power converter 3900, such as the voltage of one of nodes 3920, 3922, or 3924, or the current flowing into or out of one or more of nodes 3920, 3922, or 3924. In some embodiments, controller 3908 is configured to generate control signals Φ and Φ' using pulse width modulation (PWM), pulse frequency modulation (PFM), or another modulation technique. Optionally, controller 3908 is further configured to generate control signals Φ and Φ' for a given switching stage 3904 in an essentially complementary manner, such that a second switching device 3918 is in its off state while a first switching device 3916 is in its on state, and vice versa, wherein an optional dead time is provided between the switching states to prevent breakdown.

[0090] The boost winding 3912 and the tuning inductor 3906 are electrically coupled in series via node 3923. In some embodiments, node 3923 is a reference node of the switching power converter 3900. For example, node 3923 may be the ground plane of the switching power converter 3900.

[0091] In some embodiments, node 3920 is an input power node, node 3922 is a reference node, and node 3924 is an output power node, such that the switching power converter 3900 has a buck topology. However, the switching power converter 3900 can be configured to have an alternative topology. For example, in some embodiments, node 3924 is an input power node, node 3920 is an output power node, and node 3922 is a reference node, such that the switching power converter 3900 has a boost topology. In some alternative embodiments, the tuning inductor 3906 is omitted, such that both terminals of the boost winding 3912 are electrically coupled to node 3922. Without departing from the scope of this document, the switching power converter 3900 may include additional components. For example, some embodiments further include corresponding capacitors (not shown) electrically coupled to each node 3920 and 3924 to provide a path for ripple current and / or help support transient loads.

[0092] Making M relatively large (e.g., M is three or greater) can be particularly beneficial. Specifically, the presence of the boost winding 3912 promotes a good transient response of the switching power converter 3900, i.e., the ability of the switching power converter 3900 to quickly adapt to changes in its load. However, the presence of the boost winding 3912 increases the ripple current amplitude compared to other similar switching power converters without it. Generally, a large ripple current amplitude is undesirable because it leads to losses in the switching power converter 3900 and ripple voltage at the output power node. Increasing the inductance value of the tuning inductor 3906 helps reduce the ripple current amplitude, but increasing this inductance value also degrades the transient response of the switching power converter 3900. Therefore, when M is small (i.e., when M is less than or equal to two), there is a large trade-off between transient response and efficiency. Specifically, if the tuning inductor 3906 has a small inductance value, a good transient response can be achieved, but the ripple current amplitude will be larger. Conversely, if the tuned inductor 3906 has a larger inductance value, a smaller ripple current amplitude can be achieved, but the transient response will be worse.

[0093] However, the applicant has determined that increasing M enables the switching power converter 3900 to achieve both good transient response and good ripple current amplitude, since the ripple current amplitude decreases with increasing number of phase windings 3910. Therefore, configuring the boost coupling inductor 3902 to have a larger number of phase windings 3910 (e.g., at least three phase windings 3910) advantageously helps the switching power converter 3900 overcome the increase in ripple current amplitude associated with the presence of the boost winding 3912. Therefore, the tuning inductor 3906 can be configured to have a smaller inductance value (or even omitted) to promote good transient response, while the boost coupling inductor 3902 can be configured to have a larger number of phases to minimize ripple current amplitude. Therefore, implementing the boost coupling inductor 3902 by including at least three phase windings can be particularly advantageous. The boost-coupled inductors 100 and 1600 are scalable and can therefore include a large number of phase windings, while the boost-coupled inductor 2600 is limited to two phase windings.

[0094] Furthermore, the switching power converter 3900 can be modified to include one or more additional boost-coupled inductors. For example, Figure 40This is a schematic diagram of a switching power converter 4000, which includes K boost-coupled inductors, switching stages 4004 and 4005, a tuning inductor 4006, and a controller 4008, where K is an integer greater than one. Boost-coupled inductors 4002 (1) include M phase windings 4010, boost windings 4012, and a core 4014, where M is an integer greater than one. Boost-coupled inductors 4002 (K) include N phase windings 4011, boost windings 4013, and a core 4015, where N is an integer greater than one. Any other boost-coupled inductor 4002 (not shown) of the switching power converter 4000 may have a similar configuration. Boost-coupled inductors 4002 are embodiments of one or more of the boost-coupled inductors discussed above. The number of phase windings may vary among instances of boost-coupled inductors 4002. For example, in some embodiments, N equals M, and in some other embodiments, N does not equal M. The ripple current amplitude decreases with increasing number of boost-coupled inductors 4002, and also with increasing number of phase windings 4010, 4011 within each boost-coupled inductor. Advantageously, such reduction in ripple current can lead to improved efficiency, or it can be traded for other beneficial effects, such as improved converter transient response.

[0095] The corresponding switching stage is electrically coupled to each phase winding. For example, the corresponding switching stage 4004 is electrically coupled to each phase winding 4010, and the corresponding switching stage 4005 is electrically coupled to each phase winding 4011. Details of switching stages 4004 and 4005 are not shown, but in some embodiments, each of switching stages 4004 and 4005 is similar to Figure 39 The switch stage 3904 is configured. The controller 4008 is configured to generate control signals (not shown), thereby acting in a manner similar to that described above. Figure 39 The controller 3908 controls the switching stages of the switching power converter 4000, such as switching stages 4004 and 4005, in the manner discussed.

[0096] Each phase winding (e.g., 4010 and 4011) is electrically coupled between a corresponding switching stage (e.g., 4004 or 4005) and node 4024. In some embodiments, node 4024 is an output power node, such that the switching power converter 4000 has a buck topology, and in some other embodiments, node 4024 is an input power node, such that the switching power converter 4000 has a boost topology. However, the switching power converter 4000 may have different topologies without departing from the scope of the invention. Optionally, the boost winding (e.g., 4012 and 4013) of each boost coupling inductor 4002 is electrically coupled in series with a tuning inductor 4006, such as via Figure 40Node 4022 is shown in the diagram. In some embodiments, node 4022 is a reference node, such as the ground plane of the switching power converter 4000. In some alternative embodiments, the tuning inductor 4006 is omitted, such that the boost winding is electrically coupled in series via node 4022. Without departing from the scope of this document, the switching power converter 4000 may include additional components. For example, some embodiments further include a capacitor (not shown) electrically coupled to node 4024 to provide a path for ripple current and / or help support transient loads.

[0097] Modifications to the above-described boost-coupled inductor, system, and method may be made without departing from the scope of the invention. Therefore, it should be noted that the subject matter contained in the foregoing description and shown in the accompanying drawings should be interpreted illustratively rather than restrictively. The following claims are intended to cover all statements made herein regarding the general and specific features described herein and the scope of the boost-coupled inductor, system, and method of the invention, which may be said to fall within the scope of the invention.

Claims

1. A switching power supply converter, comprising: First switching stage; Second switching stage; A coupling inductor, comprising: First phase winding, The second phase winding, and magnetic core, The first phase winding is at least partially wound around a first portion of the magnetic core, and the first phase winding is electrically coupled to the first switching stage. The second phase winding is at least partially wound around the second portion of the magnetic core, and the second phase winding is electrically coupled to the second switching stage; and A boost winding, the boost winding forming at least one turn, such that the mutual inductance flux associated with each of the first phase winding and the second phase winding flows through the at least one turn. in: The first part of the magnetic core includes the first core post of the magnetic core; The second part of the magnetic core includes the second core post of the magnetic core; The boost winding is wound around each of the first core post and the second core post; The magnetic core further includes a first guide rail and a second guide rail that are separated from each other in a first direction; Each of the first and second core pillars is disposed between the first and second guide rails in the first direction; and The first core and the second core are separated from each other in a second direction orthogonal to the first direction.

2. The switching power supply converter of claim 1, further comprising a third switching stage, wherein: The coupled inductor further includes a third-phase winding, at least partially wound on a third portion of the magnetic core, the third-phase winding being electrically coupled to the third switching stage; and The boost winding forms the at least one turn such that the mutual inductance flux associated with each of the first phase winding, the second phase winding, and the third phase winding flows through the at least one turn.

3. The switching power supply converter as described in claim 1, wherein, Each of the first phase winding and the second phase winding is at least partially surrounded by the boost winding, as can be seen when the cross-section of the coupled inductor is viewed in the first direction.

4. The switching power supply converter as described in claim 3, wherein: The magnetic core further includes a leakage element disposed between the first guide rail and the second guide rail in the first direction; and The leakage element is positioned above the boost winding in a third direction, which is orthogonal to each of the first and second directions.

5. The switching power supply converter as described in claim 4, wherein: The leaking element is attached to the first guide rail; and The leaking element is separated from the second guide rail by a gap in the first direction.

6. The switching power converter of claim 1, further comprising a controller configured to control the switching of at least the first switching stage and the second switching stage.

7. A switching power supply converter, comprising: First switching stage; Second switching stage; A coupling inductor, comprising: First phase winding, The second phase winding, and magnetic core, The first phase winding is at least partially wound around a first portion of the magnetic core, and the first phase winding is electrically coupled to the first switching stage. The second phase winding is at least partially wound around the second portion of the magnetic core, and the second phase winding is electrically coupled to the second switching stage; and A boost winding, the boost winding forming at least one turn, such that the mutual inductance flux associated with each of the first phase winding and the second phase winding flows through the at least one turn. in: The magnetic core forms a passage extending through it in a first direction; The first phase winding is wound through the passage; The second phase winding is wound through the passage, and the second phase winding separates from the first phase winding in the passage in a second direction orthogonal to the first direction; and The boost winding is wound through the passage, such that the boost winding is positioned in the second direction between the first phase winding and the second phase winding.

8. The switching power supply converter as described in claim 7, wherein: The pathway has a height in a third direction, which is orthogonal to each of the first and second directions; The passage has a width in the second direction; and The height of the passage varies along the width of the passage such that the height of the passage at the boost winding is less than the height of the passage at each of the first phase winding and the second phase winding.

9. A switching power supply converter, comprising: A first boost-coupled inductor includes M phase windings and a first boost winding, the first boost winding forming at least one first turn such that mutual inductance flux associated with each of the M phase windings flows through the at least one first turn, where M is an integer greater than one. Electrically coupled to the corresponding switching stage of each of the M phase windings; The second boost-coupled inductor includes N phase windings and a second boost winding, the second boost winding forming at least one second turn such that mutual inductance flux associated with each of the N phase windings flows through the at least one second turn, where N is an integer greater than one. as well as Electrically coupled to the corresponding switching stage of each of the N phase windings; The first boost winding and the second boost winding are connected in series and electrically coupled.

10. The switching power supply converter as claimed in claim 9, wherein, N equals M.

11. The switching power supply converter as claimed in claim 9, wherein, N is not equal to M.

12. The switching power converter of claim 9, further comprising a controller configured to control the switching of at least two of the following: (a) each switching stage electrically coupled to each of the M phase windings; and (b) each switching stage electrically coupled to each of the N phase windings.

13. A boost-coupled inductor, comprising: A magnetic core comprising multiple core posts, a first guide rail, and a second guide rail, wherein the first guide rail and the second guide rail are separated from each other in a first direction, each of the multiple core posts is disposed between the first guide rail and the second guide rail in the first direction, and the multiple core posts are separated from each other in a second direction orthogonal to the first direction; The corresponding phase winding is at least partially wound on each of the plurality of core posts; as well as A boost winding that is at least partially wound around each of the plurality of core posts.

14. The boost-coupled inductor as claimed in claim 13, wherein, Each phase winding is at least partially surrounded by the boost winding, as can be seen when the cross-section of the coupled inductor is viewed in the first direction.

15. The boost-coupled inductor as claimed in claim 13, wherein: The magnetic core further includes a leakage element disposed between the first guide rail and the second guide rail in the first direction; and The leakage element is positioned above the boost winding in a third direction, which is orthogonal to each of the first and second directions.

16. The boost-coupled inductor of claim 15, wherein: The leaking element is attached to the first guide rail; and The leaking element is separated from the second guide rail by a gap in the first direction.

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