Magnetic component, power conversion device, and power conversion system

Abstract

A magnetic component of the present application has a magnetic core, a first terminal, a second terminal, a first winding, and one or more second windings. The magnetic core has two base portions facing each other and five leg portions including a first leg portion, a second leg portion, a third leg portion, a fourth leg portion, and a fifth leg portion disposed in facing surfaces of the two base portions and magnetically coupling the two base portions. The second leg portion and the third leg portion are disposed to sandwich the first leg portion in a first direction, and the fourth leg portion and the fifth leg portion are disposed to sandwich the first leg portion in a second direction. The first winding is wound in a first winding direction on the first leg portion, the second leg portion, and the third leg portion in a direction from the first terminal toward the second terminal, and is wound in a second winding direction on the fourth leg portion and the fifth leg portion. The one or more second windings are wound on four of the five leg portions other than the first leg portion.

Description

Technical Field

[0001] The present invention relates to a magnetic component, a power conversion device having the magnetic component, and a power conversion system having such a power conversion device. Background Technology

[0002] Power conversion devices can be resonant converters constructed using resonant coils and transformers. In power conversion devices, it is desirable to reduce component costs and installation costs, and to achieve miniaturization of the device. To meet these requirements, magnetic components combining resonant coils and transformers have been developed, for example (e.g., Patent Documents 1, 2).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2014-63856

[0006] Patent Document 2: U.S. Patent Application Publication No. 2017 / 0345541 Summary of the Invention

[0007] One type of power conversion device is the LLC resonant converter. In an LLC resonant converter, frequency control is used to stabilize the output voltage. Under such frequency control, a larger voltage is applied to the resonant coil to operate over a wider input voltage range, thus increasing the magnetic flux through the coil core. Therefore, the effective cross-sectional area of ​​the core needs to be increased. Furthermore, because the inductance of the resonant coil needs to be increased, the volume of the coil section increases. This results in a larger resonant coil size. In power conversion devices, the resonant coil and transformer account for a significant portion of the device's volume. Therefore, it is desirable to reduce the height of magnetic components such as the resonant coil and transformer to decrease the overall size.

[0008] It is desirable to provide a magnetic component, power conversion device, and power conversion system that can reduce size.

[0009] The first magnetic component of one embodiment of the present application includes a magnetic core, a first terminal, a second terminal, a first winding, and one or more second windings. The magnetic core includes two leg portions facing each other and five leg portions including a first leg portion, a second leg portion, a third leg portion, a fourth leg portion, and a fifth leg portion which are arranged in facing surfaces of the two leg portions and magnetically couple the two leg portions. The second leg portion and the third leg portion are arranged to sandwich the first leg portion in a first direction, and the fourth leg portion and the fifth leg portion are arranged to sandwich the first leg portion in a second direction. The first winding is wound on the first leg portion, the second leg portion, and the third leg portion in a first winding direction and on the fourth leg portion and the fifth leg portion in a second winding direction in a direction from the first terminal toward the second terminal. The one or more second windings are wound on four of the five leg portions excluding the first leg portion.

[0010] The second magnetic component of one embodiment of the present application includes a magnetic core, a first terminal, a second terminal, a first winding, and one or more second windings. The magnetic core includes two leg portions facing each other and six leg portions including a first leg portion, a second leg portion, a third leg portion, a fourth leg portion, a fifth leg portion, and a sixth leg portion which are arranged in facing surfaces of the two leg portions and magnetically couple the two leg portions. The first leg portion, the second leg portion, and the third leg portion are arranged in a first direction, the fourth leg portion, the fifth leg portion, and the sixth leg portion are arranged in the first direction, the first leg portion and the fourth leg portion are arranged in a second direction, the second leg portion and the fifth leg portion are arranged in the second direction, and the third leg portion and the sixth leg portion are arranged in the second direction. The first winding is wound on the first leg portion, the third leg portion, and the fifth leg portion in a first winding direction and on the second leg portion, the fourth leg portion, and the sixth leg portion in a second winding direction in a direction from the first terminal toward the second terminal. The one or more second windings are wound on four of the six leg portions excluding the first leg portion and the sixth leg portion.

[0011] The first power conversion device of one embodiment of the present application includes the above-described first magnetic component or second magnetic component, a switching circuit, a rectifier circuit, and a smoothing circuit. The switching circuit is connected to at least one of the first terminal and the second terminal of the magnetic component and includes one or more switching elements. The rectifier circuit is connected to the one or more second windings of the magnetic component. The smoothing circuit is connected to the rectifier circuit.

[0012] The second power conversion device of one embodiment of the present application includes the above-described first magnetic component or second magnetic component, a switching circuit, a rectifier circuit, and a smoothing circuit. The switching circuit is connected to the one or more second windings of the magnetic component and includes one or more switching elements. The rectifier circuit is connected to the first terminal and the second terminal of the magnetic component. The smoothing circuit is connected to the rectifier circuit.

[0013] The power conversion system of one embodiment of the present application includes the first power conversion device or the second power conversion device, a first battery, and a second battery. The first battery is connected to the switching circuit of the power conversion device. The second battery is connected to the smoothing circuit of the power conversion device.

[0014] The first magnetic member, the second magnetic member, the first power conversion device, the second power conversion device, and the power conversion system according to one embodiment of the present application can reduce the size. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 FIG. 1 is a circuit diagram illustrating one structure example of a power conversion device according to a first embodiment of the present application.

[0016] Figure 2 FIG. 2 is a diagram illustrating one structure example of a transformer illustrated in FIG. 1. Figure 1

[0017] Figure 3 FIG. 3 is a diagram illustrating one structure example of a winding illustrated in FIG. 1. Figure 1

[0018] Figure 4 FIG. 4 is a timing waveform chart illustrating one operation example of the power conversion device illustrated in FIG. 1. Figure 1

[0019] Figure 5A FIG. 5 is a diagram illustrating one operation state of the power conversion device illustrated in FIG. 1. Figure 1

[0020] Figure 5B FIG. 6 is a diagram illustrating another operation state of the power conversion device illustrated in FIG. 1. Figure 1

[0021] Figure 6A FIG. 7 is a diagram illustrating one example of magnetic flux of a foot portion illustrated in FIG. 1. Figure 3

[0022] Figure 6B FIG. 8 is a diagram illustrating another example of magnetic flux of the foot portion illustrated in FIG. 1. Figure 3

[0023] Figure 7A FIG. 9 is a diagram illustrating one example of magnetic flux of a base portion illustrated in FIG. 1. Figure 3

[0024] Figure 7B FIG. 10 is a diagram illustrating another example of magnetic flux of the base portion illustrated in FIG. 1. Figure 3

[0025] Figure 8 ​​​​​​​​​is a circuit diagram showing one configuration example of the power conversion device of the first embodiment.

[0026] Figure 9 is a configuration example of the winding shown in Figure 8

[0027] Figure 10 is a circuit diagram showing one configuration example of the power conversion device of the first embodiment.

[0028] Figure 11 is a configuration example of the winding shown in Figure 10

[0029] Figure 12 is a timing waveform diagram showing one operation example of the power conversion device shown in Figure 10

[0030] Figure 13A is a configuration example of the winding shown in Figure 10

[0031] Figure 13B is a configuration example of the winding shown in Figure 10

[0032] Figure 14 is a circuit diagram showing one configuration example of the power conversion device of the first embodiment.

[0033] Figure 15 is a configuration example of the transformer of the first embodiment.

[0034] Figure 16 is a circuit diagram showing one configuration example of the power conversion device of the second embodiment.

[0035] Figure 17 is a configuration example of the transformer shown in Figure 16

[0036] Figure 18 is a configuration example of the winding shown in Figure 16

[0037] Figure 19A is a configuration example of the winding shown in Figure 18

[0038] Figure 19B is a configuration example of the winding shown in Figure 18

[0039] ​​​​​​​​​Figure 20A is a diagram showing an example of magnetic flux of the base portion. Figure 18

[0040] Figure 20B is a diagram showing another example of magnetic flux of the base portion. Figure 18

[0041] Figure 21 is a diagram showing one configuration example of a transformer of a modification example of the second embodiment.

[0042] Figure 22 is a diagram showing one configuration example of a power conversion system of the modification example. DETAILED DESCRIPTION

[0043] Hereinafter, an embodiment of the present application will be described in detail with reference to the drawings.

[0044] <EMBODIMENT>

[0045] [CONFIGURATION EXAMPLE]

[0046] Figure 1 One configuration example of a power conversion device 1 provided with a transformer of one embodiment of the present application is shown. The power conversion device 1 is an LLC resonant converter that converts direct-current power. The power conversion device 1 is provided with terminals T11, T12 and terminals T21, T22. The terminals T11, T12 are connected to a direct-current power supply PDC, and the terminals T21, T22 are connected to a load LD. The power conversion device 1 is configured to convert direct-current power supplied from the direct-current power supply PDC and supply the converted direct-current power to the load LD.

[0047] The power conversion device 1 is provided with a capacitor 11, a switching circuit 12, a capacitor 15, a transformer 20, four rectifier circuits 16 (rectifier circuits 16A, 16B, 16C, 16D), and four smoothing circuits 17 (smoothing circuits 17A, 17B, 17C, 17D). The capacitor 11, the switching circuit 12, and the capacitor 15 constitute a primary side circuit of the power conversion device 1, and the four rectifier circuits 16 and the four smoothing circuits 17 constitute a secondary side circuit of the power conversion device 1.

[0048] One end of the capacitor 11 is connected to a voltage line L11 that is led to the terminal T11, and the other end is connected to a reference voltage line L12 that is led to the terminal T12.

[0049] ​​The switching circuit 12 is configured to convert a direct current voltage supplied from the direct current power supply PDC into an alternating current voltage. The switching circuit 12 has transistors 13, 14. The transistors 13, 14 are MOS-FETs (Metal Oxide Semiconductor-Field Effect Transistor) in this example. The drain of the transistor 13 is connected to the voltage line Ll l, the source is connected to the drain of the transistor 14 and one end of a capacitor 15, and the gate is supplied with a gate signal Gl from a control section not shown. The drain of the transistor 14 is connected to the source of the transistor 13 and one end of the capacitor 15, the source is connected to the reference voltage line L12, and the gate is supplied with a gate signal G2 from the control section not shown. Note that the switching circuit 12 is not limited to this configuration, and various circuits having one or more switching elements can be used.

[0050] One end of the capacitor 15 is connected to the source of the transistor 13 and the drain of the transistor 14, and the other end is connected to a terminal Tl (described later) of a transformer 20.

[0051] The transformer 20 is configured to insulate a primary side circuit from a secondary side circuit in a direct current manner and connect them in an alternating current manner, convert an alternating current voltage supplied from the primary side circuit at a transformer ratio R of the transformer 20, and supply the converted alternating current voltage to the secondary side circuit. The transformer 20 is a composite magnetic component of a resonant coil and a transformer. The transformer 20 has terminals Tl, T2, T3A, T4A, T5A, T3B, T4B, T5B, T3C, T4C, T5C, T3D, T4D, T5D, a winding 21, and windings 22A, 23A, 22B, 23B, 22C, 23C, 22D, 23D.

[0052] The terminal Tl is connected to the other end of the capacitor 15, and the terminal T2 is connected to the reference voltage line L12. The terminals T3A, T5A are connected to the reference voltage line L22 guided to the terminal T22 through a rectifier circuit 16A, and the terminal T4A is connected to the voltage line L21 guided to the terminal T21. The terminals T3B, T5B are connected to the reference voltage line L22 through the rectifier circuit 16B, and the terminal T4B is connected to the voltage line L21. The terminals T3C, T5C are connected to the reference voltage line L22 through the rectifier circuit 16C, and the terminal T4C is connected to the voltage line L21. The terminals T3D, T5D are connected to the reference voltage line L22 through the rectifier circuit 16D, and the terminal T4D is connected to the voltage line L21.

[0053] One end of the winding 21 is connected to the terminal Tl and the other end is connected to the terminal T2. The winding 21 includes windings 21A, 21B, 21C, 21D, 21E. The winding 21A is a resonance coil and the windings 21B to 21E are primary side windings of a transformer. The windings 21A to 21E are connected in series. The winding 21A is connected to the terminal Tl and the winding 21E is connected to the terminal T2.

[0054] One end of the winding 22A is connected to the terminal T3A and the other end is connected to the terminal T4A. One end of the winding 23A is connected to the terminal T4A and the other end is connected to the terminal T5A. One end of the winding 22B is connected to the terminal T3B and the other end is connected to the terminal T4B. One end of the winding 23B is connected to the terminal T4B and the other end is connected to the terminal T5B. One end of the winding 22C is connected to the terminal T3C and the other end is connected to the terminal T4C. One end of the winding 23C is connected to the terminal T4C and the other end is connected to the terminal T5C. One end of the winding 22D is connected to the terminal T3D and the other end is connected to the terminal T4D. One end of the winding 23D is connected to the terminal T4D and the other end is connected to the terminal T5D.

[0055] The rectifier circuit 16A is configured to rectify the alternating voltage output from the windings 22A, 23A of the transformer 20. The rectifier circuit 16A has diodes Dl, D2. The diode Dl is disposed on the reference voltage line L22, has its anode connected to the anode of the diode D2 and the smoothing circuit 17A, and has its cathode connected to the terminal T3A of the transformer 20. The diode D2 is disposed on the reference voltage line L22, has its anode connected to the anode of the diode Dl and the smoothing circuit 17A, and has its cathode connected to the terminal T5A of the transformer 20. In this example, although diodes are provided, the present application is not limited thereto and, for example, a transistor can be provided in place of the diodes to perform so-called synchronous rectification.

[0056] The rectifier circuit 16B is configured to rectify the alternating voltage output from the windings 22B, 23B of the transformer 20. The rectifier circuit 16C is configured to rectify the alternating voltage output from the windings 22C, 23C of the transformer 20. The rectifier circuit 16D is configured to rectify the alternating voltage output from the windings 22D, 23D of the transformer 20. The circuit structures of the rectifier circuits 16B to 16D are the same as the circuit structure of the rectifier circuit 16A.

[0057] The smoothing circuit 17A is configured to smooth the voltage rectified by the rectifier circuit 16A. The smoothing circuit 17A has a capacitor 18. One end of the capacitor 18 is connected to the voltage line L21, and the other end is connected to the reference voltage line L22. Note that, in this example, although the smoothing circuit 17A has the capacitor 18, the present application is not limited thereto, and for example, an inductor provided between one end of the capacitor 18 and the terminal T4A of the transformer 20 can be used.

[0058] The smoothing circuit 17B is configured to smooth the voltage rectified by the rectifier circuit 16B. The smoothing circuit 17C is configured to smooth the voltage rectified by the rectifier circuit 16C. The smoothing circuit 17D is configured to smooth the voltage rectified by the rectifier circuit 16D. The circuit structures of the smoothing circuits 17B to 17D are the same as that of the smoothing circuit 17A.

[0059] (Transformer 20)

[0060] Figure 2 A configuration example of the transformer 20 is shown. In Figure 2 , a cross-sectional view of the transformer 20 in the direction of the arrow I-I and a cross-sectional view of the transformer 20 in the direction of the arrow II-II are also described. The transformer 20 is a planar transformer in this example. The transformer 20 has a magnetic core 100 and a substrate 200.

[0061] The magnetic core 100 has base portions 101, 102 and five leg portions 111 to 115. The base portions 101, 102 are opposed in the Z direction. The base portions 101, 102 have a substantially rectangular shape in the XY plane along the X direction. The leg portions 111 to 115 are arranged in the facing surfaces of the two base portions 101, 102, and are provided so as to magnetically couple the two base portions 101, 102. The leg portion 111 is provided near the center of the base portions 101, 102. The leg portions 112, 113 are provided at both ends in the X direction of the base portions 101, 102, and the leg portions 114, 115 are provided at both ends in the Y direction of the base portions 101, 102. That is, the leg portions 112, 113 are arranged to sandwich the leg portion 111 in the X direction, and the leg portions 114, 115 are arranged to sandwich the leg portion 111 in the Y direction. In the XY plane, the cross-sectional area of the leg portions 114, 115 is larger than that of the leg portions 112, 113. The leg portions 111, 114, 115 are configured to be elongated in the X direction in the XY plane, and the leg portions 112, 113 are configured to be elongated in the Y direction in the XY plane. The width of the leg portions 114, 115 in the X direction is wider than that of the leg portions 112, 113 in the Y direction.

[0062] The substrate 200 is a multi-layer substrate (4-layer substrate in this example). Through-holes are provided in the substrate 200 at positions corresponding to the leg portions 111 to 115 of the magnetic core 100, and the substrate 200 is sandwiched between the base portions 101, 102 of the magnetic core 100. On this substrate 200, the winding 21 and the windings 22A, 23A, 22B, 23B, 22C, 23C, 22D, 23D are provided.

[0063] Figure 3 One example of a structure of the windings of the substrate 200 is shown in FIG. 6. Figure 3 (A) indicates the first layer, i.e., the wiring layer LA1, Figure 3 (B) indicates the second layer, i.e., the wiring layer LA2, Figure 3 (C) indicates the third layer, i.e., the wiring layer LA3, Figure 3 (D) indicates the fourth layer, i.e., the wiring layer LA4. The wiring layers LA1 to LA4 are provided in the layer direction of the substrate 200 in this order. Figure 3 In FIG. 6, the winding 21 is shown by a solid line, and the windings 22A, 23A, 22B, 23B, 22C, 23C, 22D, 23D are shown by broken lines.

[0064] On the wiring layers LA2, LA3, the winding 21 (windings 21A, 21B, 21C, 21D, 21E) is provided. On the substrate 200, through-holes TH1 to TH6 are provided which connect the wiring of the wiring layer LA2 and the wiring of the wiring layer LA3. The winding 21 is formed in such a manner as to include these through-holes TH1 to TH6, and is connected to the terminals T1, T2. The winding 21 is wound around the five leg portions 111 to 115. Specifically, the winding 21 is wound around the leg portions 111, 112, 113 in the clockwise direction and around the leg portions 114, 115 in the counterclockwise direction, respectively, for two turns in the direction from the terminal T1 toward the terminal T2. The portion of the winding 21 wound around the leg portion 111 corresponds to the winding 21A which is a resonance coil, and the portions wound around the leg portions 112 to 115 correspond to the windings 21B to 21D which are primary windings of a transformer.

[0065] On the wiring layer LA1, the windings 22A, 22B, 22C, 22D are provided. The winding 22A is wound around the leg portion 112 in the clockwise direction for one turn in the direction from the terminal T3A toward the terminal T4A. The winding 22B is wound around the leg portion 115 in the counterclockwise direction for one turn in the direction from the terminal T3B toward the terminal T4B. The winding 22C is wound around the leg portion 113 in the clockwise direction for one turn in the direction from the terminal T3C toward the terminal T4C. The winding 22D is wound around the leg portion 114 in the counterclockwise direction for one turn in the direction from the terminal T3D toward the terminal T4D.

[0066] On the wiring layer LA4, the windings 23A, 23B, 23C, 23D are provided. The winding 23A is wound 1 turn on the leg portion 112 in the counterclockwise direction in the direction from the terminal T5A toward the terminal T4A. The winding 23B is wound 1 turn on the leg portion 115 in the clockwise direction in the direction from the terminal T5B toward the terminal T4B. The winding 23C is wound 1 turn on the leg portion 113 in the counterclockwise direction in the direction from the terminal T5C toward the terminal T4C. The winding 23D is wound 1 turn on the leg portion 114 in the clockwise direction in the direction from the terminal T5D toward the terminal T4D.

[0067] Here, the transformer 20 corresponds to one specific example of the "magnetic component" of the present disclosure. The magnetic core 100 corresponds to one specific example of the "magnetic core" of the present disclosure. The leg portion 111 corresponds to one specific example of the "first leg portion" of the present disclosure. The leg portion 112 corresponds to one specific example of the "second leg portion" of the present disclosure. The leg portion 113 corresponds to one specific example of the "third leg portion" of the present disclosure. The leg portion 114 corresponds to one specific example of the "fourth leg portion" of the present disclosure. The leg portion 115 corresponds to one specific example of the "fifth leg portion" of the present disclosure. The terminal T1 corresponds to one specific example of the "first terminal" of the present disclosure. The terminal T2 corresponds to one specific example of the "second terminal" of the present disclosure. The winding 21 corresponds to one specific example of the "first winding" of the present disclosure. The windings 22A, 23A, 22B, 23B, 22C, 23C, 22D, 23D correspond to one specific example of the "a plurality of second windings" of the present disclosure. The switching circuit 12 corresponds to one specific example of the "switching circuit" of the present disclosure. The transformer 20 corresponds to one specific example of the "transformer" of the present disclosure. The rectifier circuits 16A, 16B, 16C, 16D correspond to one specific example of the "rectifier circuit" of the present disclosure. The smoothing circuits 17A, 17B, 17C, 17D correspond to one specific example of the "smoothing circuit" of the present disclosure.

[0068] [Actions and Effects]

[0069] Next, the actions and effects of the power conversion device 1 of the present embodiment will be described.

[0070] (Overall Action Outline)

[0071] First, the configuration of the power conversion device 1 of the present embodiment will be described with reference to FIG. 1. Figure 1This section describes the overall operation of the power conversion device 1. In the switching circuit 12 of the power conversion device 1, transistors 13 and 14 perform the conversion operation, generating an AC voltage based on the DC voltage supplied from the DC power supply PDC. The transformer 20 converts this AC voltage at a transformation ratio R. Rectifier circuit 16A rectifies the AC voltage output from windings 22A and 23A of the transformer 20; rectifier circuit 16B rectifies the AC voltage output from windings 22B and 23B of the transformer 20; rectifier circuit 16C rectifies the AC voltage output from windings 22C and 23C of the transformer 20; and rectifier circuit 16D rectifies the AC voltage output from windings 22D and 23D of the transformer 20. Smoothing circuit 17A smooths the voltage rectified by rectifier circuit 16A, smoothing circuit 17B smooths the voltage rectified by rectifier circuit 16B, smoothing circuit 17C smooths the voltage rectified by rectifier circuit 16C, and smoothing circuit 17D smooths the voltage rectified by rectifier circuit 16D.

[0072] (Detailed actions)

[0073] Figure 4 This represents an example of the operation of power conversion device 1. Figure 4 In this diagram, I1 represents the current flowing through winding 21, I2 represents the total current flowing through windings 22A, 23A, 22B, 23B, 22C, 23C, 22D, and 23D, and Im represents the magnetizing current. This magnetizing current Im is represented by I1 - I2·R. R is the transformation ratio of transformer 20. The transformation ratio R is the value obtained by dividing the number of turns of the primary winding (windings 21B to 21E) of the transformer by the number of turns of the secondary winding (e.g., winding 22A).

[0074] In this example, at time t0, the gate signal G2 transitions from high to low. Consequently, transistors 13 and 14 are both turned off.

[0075] At time t1, the gate signal G1 changes from low to high. This turns transistor 13 on. During the period from t1 to t2, transistor 13 remains on, and transistor 14 remains off. Then, at time t2, the gate signal G1 changes from high to low. This turns transistor 13 off.

[0076] At time t3, the gate signal G2 transitions from low to high. This turns transistor 14 on. During the period from t3 to t4, transistor 13 remains off, and transistor 14 remains on. Then, at time t4, the gate signal G2 transitions from high to low. This turns transistor 14 off.

[0077] At time t5, the gate signal Gl transitions from low to high. Thus, the transistor 13 becomes an on state.

[0078] By the switching operation of the transistors 13, 14 in this way, in the transformer 20, as shown in FIG. 6B, the currents I1, I2 and the magnetizing current Im flow. Specifically, the current I2 flowing through the secondary side of the transformer 20 becomes a sinusoidal current that is positive during the period from time tO to t2 and negative during the period from time t2 to t4. In addition, the current I1 flowing through the primary side of the transformer 20 becomes a sinusoidal current that is in phase with the current I2. The magnetizing current Im becomes a triangular wave current that increases during the period from time tO to t2 and decreases during the period from time t2 to t4. Figure 4

[0079] Figure 5A ,5B indicates the direction of the magnetic flux of the foot portions 111 to 115 of the magnetic core 100, Figure 5A indicates the operation at a certain time tA during the period from time t1 to t2, Figure 5B indicates the operation at a certain time tB during the period from time t3 to t4. In these drawings, the transistors 13, 14 are indicated by symbols that indicate their operating states (on state or off state).

[0080] Figure 6A ,6B indicates the direction of the magnetic flux of the foot portions 111 to 115 of the magnetic core 100, Figure 6A indicates the direction of the magnetic flux at time tA, Figure 6B indicates the direction of the magnetic flux at time tB. Figure 7A ,7B indicates the direction of the magnetic flux of the base portion 102 of the magnetic core 100, Figure 7A indicates the direction of the magnetic flux at time tA, Figure 7B indicates the direction of the magnetic flux at time tB.

[0081] During the period from time t1 to t2, as shown in FIG. 5B, the transistor 13 is in an on state and the transistor 14 is in an off state. Thus, at a certain time tA during the period from time t1 to t2, as shown in FIG. 5C, in the primary side circuit, the current IA1 flows through the transistor 13, the capacitor 15, the terminal T1, the winding 21, and the terminal T2 in this order. Corresponding to this current IA1, in the secondary side circuit of the rectification circuit 16A and the smoothing circuit 17A, for example, the current IA2 flows through the winding 23A, the terminal T4A, the capacitor 18, and the load LD, the diode D2, and the terminal T5A in this order. The same applies to the secondary side circuits of the rectification circuit 16B and the smoothing circuit 17B, the secondary side circuits of the rectification circuit 16C and the smoothing circuit 17C, and the secondary side circuits of the rectification circuit 16D and the smoothing circuit 17D. Figure 4 Figure 5A

[0082] ​​​In this way, in winding 21, current IA1 flows from terminal T1 to terminal T2, and in transformer 20, as... Figure 6A As shown, magnetic flux is generated in the feet 111-115. Because the windings 21 are wound clockwise on feet 111, 112, and 113, and counterclockwise on feet 114 and 115, the direction of the magnetic flux in feet 111, 112, and 113 is opposite to the Z-direction, while the direction of the magnetic flux in feet 114 and 115 is in the Z-direction. In the base portion 102, as... Figure 7A As shown, magnetic flux is generated from foot 111 towards foot 114, 115, magnetic flux is generated from foot 112 towards foot 114, 115, and magnetic flux is generated from foot 113 towards foot 114, 115. The direction of the magnetic flux in base portion 101 is the same as the direction of the magnetic flux in base portion 102. Figure 7A (The opposite direction)

[0083] During the period from time t3 to t4, such as Figure 4 As shown, transistor 13 is in the off state, and transistor 14 is in the on state. Therefore, at a certain time tB between times t3 and t4, as... Figure 5B As shown, in the primary circuit, current IB1 flows sequentially through capacitor 15, transistor 14, terminal T2, winding 21, and terminal T1. Corresponding to this current IB1, for example, in the secondary circuit of rectifier circuit 16A and smoothing circuit 17A, current IB2 flows sequentially through winding 22A, terminal T4A, capacitor 18 and load LD, diode D1, and terminal T3A. The same applies to the secondary circuits of rectifier circuit 16B and smoothing circuit 17B, rectifier circuit 16C and smoothing circuit 17C, and rectifier circuit 16D and smoothing circuit 17D.

[0084] In this way, in winding 21, current IB1 flows from terminal T2 to terminal T1, and in transformer 20, as... Figure 6B As shown, magnetic flux is generated in the feet 111-115. The direction of the magnetic flux in feet 111, 112, and 113 is the Z-direction, while the direction of the magnetic flux in feet 114 and 115 is opposite to the Z-direction. In the base 102, as... Figure 7B As shown, magnetic flux is generated from foot 114 toward foot 111, 112, 113, and magnetic flux is generated from foot 115 toward foot 111, 112, 113. The direction of the magnetic flux in base 101 is the same as the direction of the magnetic flux in base 102. Figure 7B (The opposite direction)

[0085] The power conversion device 1 transforms and outputs the DC power supplied from the DC power source PDC by repeatedly performing this operation. The power conversion device 1 uses PWM (Pulse Width Modulation) to control the operation of transistors 13 and 14, thereby making the output voltage constant.

[0086] In the power conversion device 1, five feet 111 to 115 are provided. Feet 112 and 113 are configured to sandwich foot 111 in the X direction, and feet 114 and 115 are configured to sandwich foot 111 in the Y direction. Furthermore, in the direction from terminal T1 to terminal T2, winding 21 is wound around feet 111, 112, and 113 along a first winding direction, and winding 21 is wound around feet 114 and 115 along a second winding direction. Thus, in the transformer 20, as... Figure 7A As shown in Figure 7B, magnetic flux in a first direction is generated in feet 111, 112, and 113, and magnetic flux in a second direction is generated in feet 114 and 115. Thus, the magnetic flux is dispersed in the base portions 101 and 102. In this way, by dispersing the magnetic flux in the base portions 101 and 102, the magnetic flux density of the base portions 101 and 102 can be reduced, thereby reducing the height of the base portions 101 and 102 in the Z direction. Furthermore, because five feet 111 to 115 are arranged in this way, the number of turns of the winding 21 in each foot 111 to 115 can be suppressed, for example, reducing the number of layers in the substrate 200, thereby reducing the height of the feet 111 to 115 in the Z direction. As a result, the size of the transformer 20 in the power conversion device 1 can be reduced.

[0087] In particular, in the power conversion device 1, the cross-sectional areas of the feet 114 and 115 are made larger than the cross-sectional areas of the feet 112 and 113, and the width of the feet 114 and 115 in the X direction is made wider than the width of the feet 112 and 113 in the Y direction. Therefore, in the power conversion device 1, for example at the moment when the primary current I1 is at its maximum ( Figure 4 At times t6 and t7, the large magnetic flux from the foot 111, which has only a primary winding, through the base portion 101 toward the feet 114 and 115 can be dispersed. Therefore, in the power conversion device 1, the large magnetic flux generated by the resonant coil when the current of the resonant coil is at its maximum can be dispersed, reducing the magnetic flux density. At this time, because the magnetic flux generated in the feet 112 and 113 is canceled by the current I2, whose flow direction is opposite to that of the current I1 flowing on the primary side, the same magnetic flux distribution as that of a three-foot core such as an EI core or an EE core with three feet 111, 114, and 115 is achieved. In addition, for example, at the time when the excitation current Im is at its maximum ( Figure 4At times t0, t2, the magnetic flux of transformer 20 is at its maximum. At this time, no current I2 flows on the secondary side, and the magnetic flux is generated by the current I1 on the primary side in the five pins 111-115, as shown below. Figure 7A As shown in 7B, the magnetic flux can be distributed in the base portion 101, 102. As a result, the size of the transformer 20 can be effectively reduced.

[0088] Furthermore, in the power conversion device 1, winding 21 is wound on five legs 111-115, and windings 22A, 23A, 22B, 23B, 22C, 23C, 22D, and 23D are wound on four legs 112-115 other than leg 111. This allows the portion of winding 21 wound on leg 111 to function as a resonant coil. Therefore, since the resonant coil and transformer can be combined in the transformer 20, the size of the power conversion device 1 can be reduced compared to having the resonant coil and transformer installed separately. Additionally, because the inductance of the resonant coil can be increased, the power conversion device 1 (LLC resonant converter) can significantly change the ratio of output voltage to input voltage by changing the conversion frequency. Therefore, because the power conversion device 1 can control the output voltage to a constant value over a wide input voltage range through frequency control, it can operate over a wide input voltage range.

[0089] [Effect]

[0090] As described above, in this embodiment, five legs 111 to 115 are provided, with legs 112 and 113 arranged to sandwich leg 111 in the X direction, and legs 114 and 115 arranged to sandwich leg 111 in the Y direction. Furthermore, in the direction from terminal T1 to terminal T2, winding 21 is wound around legs 111, 112, and 113 along a first winding direction, and winding 21 is wound around legs 114 and 115 along a second winding direction. This allows for a reduction in the size of the transformer. In particular, because the cross-sectional area of ​​legs 114 and 115 is larger than that of legs 112 and 113, and the width of legs 114 and 115 in the X direction is wider than the width of legs 112 and 113 in the Y direction, the size of the transformer can be effectively reduced.

[0091] In this embodiment, since the winding 21 is wound on the five legs 111 to 115, and the windings 22A, 23A, 22B, 23B, 22C, 23C, 22D, and 23D are wound on the four legs 112 to 115 other than the leg 111, the size of the power conversion device can be reduced and it can operate over a wide range of input voltages.

[0092] [Variation Example 1-1]

[0093] In the above embodiment, although the winding 21 is configured by the series connection of the windings 21A, 21B, 21C, 21D, 21E in the transformer 20, the present application is not limited thereto. Hereinafter, the power conversion device 1A of the present modification will be described in detail.

[0094] Figure 8 Fig. 27 shows one configuration example of the power conversion device 1A. The power conversion device 1A is provided with a transformer 20A. The transformer 20A has a winding 21. One end of the winding 21 is connected to a terminal T1, and the other end is connected to a terminal T2. The winding 21 includes windings 21A, 21B, 21C, 21D, 21E. One end of the winding 21A is connected to the terminal T1, and the other end is connected to one end of the windings 21B, 21D. One end of the winding 21B is connected to the other end of the winding 21A, and the other end is connected to one end of the winding 21C. One end of the winding 21C is connected to the other end of the winding 21B, and the other end is connected to the terminal T2. One end of the winding 21D is connected to the other end of the winding 21A, and the other end is connected to one end of the winding 21E. One end of the winding 21E is connected to the other end of the winding 21D, and the other end is connected to the terminal T2. That is, the windings 21B, 21C are connected in parallel to the windings 21D, 21E.

[0095] Figure 9 Fig. 28 shows one configuration example of the winding of the substrate 200 of the transformer 20A. The winding 21 is provided on the wiring layers LA2 to LA4. On the substrate 200, a through-hole TH11 connecting a wiring of the wiring layer LA3 and a wiring of the wiring layer LA4, and through-holes TH12 to TH16 connecting a wiring of the wiring layer LA2 and a wiring of the wiring layer LA3 are provided. The winding 21 is configured in such a manner as to include these through-holes TH11 to TH16, and is connected to the terminals T1, T2. The winding 21 is wound around the five leg portions 111 to 115. Specifically, the winding 21 is wound around the leg portion 111 in the clockwise direction three times, around the leg portions 112, 113 in the clockwise direction two times each, and around the leg portions 114, 115 in the counterclockwise direction two times each in the direction from the terminal T1 toward the terminal T2. The portion of the winding 21 wound around the leg portion 111 corresponds to the winding 21A which is a resonance coil, and the portions wound around the leg portions 112 to 115 correspond to the windings 21B to 21D which are primary windings of the transformer.

[0096] [Modification 1-2]

[0097] In the above embodiment, although the switching circuit 12 is configured using two transistors 13, 14 and each rectifying circuit 16 is configured using two diodes D1, D2, the present application is not limited thereto. Hereinafter, the power conversion device 1B of the present modification will be described in detail.

[0098] Figure 10 FIG. 1B shows a structure example of the power conversion device 1B. The power conversion device 1B includes the capacitor 11, the switching circuit 32, the capacitor 15, the transformer 20B, the rectifier circuit 36, and the smoothing circuit 37.

[0099] The switching circuit 32 is a so-called full-bridge type circuit in this example, and includes transistors Q1 to Q4. The drain of the transistor Q1 is connected to the voltage line L11, the source is connected to the node N1, and the gate is supplied with a gate signal G1 from a control section not shown. The drain of the transistor Q2 is connected to the node N1, the source is connected to the reference voltage line L12, and the gate is supplied with a gate signal G2 from the control section not shown. The drain of the transistor Q3 is connected to the voltage line L11, the source is connected to the node N2, and the gate is supplied with a gate signal G3 from the control section not shown. The drain of the transistor Q4 is connected to the node N2, the source is connected to the reference voltage line L12, and the gate is supplied with a gate signal G4 from the control section not shown.

[0100] One end of the capacitor 15 is connected to the node N1 of the switching circuit 32, and the other end is connected to the terminal T1 of the transformer 20B.

[0101] The transformer 20B has the terminals T1, T2, T6, T7, T8, T9 and the windings 21, 26, 27.

[0102] The terminal T1 is connected to the other end of the capacitor 15, and the terminal T2 is connected to the node N2 of the switching circuit 32. The terminals T6, T8 are connected to the node N3 (described later) of the rectifier circuit 36, and the terminals T7, T9 are connected to the node N4 (described later) of the rectifier circuit 36.

[0103] One end of the winding 26 is connected to the terminal T6, and the other end is connected to the terminal T7. The winding 26 includes windings 26A, 26B. The windings 26A, 26B are connected in series. The winding 26A is connected to the terminal T6, and the winding 26B is connected to the terminal T7.

[0104] One end of the winding 27 is connected to the terminal T8, and the other end is connected to the terminal T9. The winding 27 includes windings 27A, 27B. The windings 27A, 27B are connected in series. The winding 27A is connected to the terminal T8, and the winding 27B is connected to the terminal T9.

[0105] The rectifier circuit 36 is configured to rectify the alternating voltage output from the transformer 20B. The rectifier circuit 36 has transistors Q5 to Q8. The drain of the transistor Q5 is connected to the voltage line L21, the source is connected to the node N3, and the gate is supplied with a gate signal G5 from a control section not shown. The drain of the transistor Q6 is connected to the node N3, the source is connected to the reference voltage line L22, and the gate is supplied with a gate signal G6 from the control section not shown. The drain of the transistor Q7 is connected to the voltage line L21, the source is connected to the node N4, and the gate is supplied with a gate signal G7 from the control section not shown. The drain of the transistor Q8 is connected to the node N4, the source is connected to the reference voltage line L22, and the gate is supplied with a gate signal G8 from the control section not shown.

[0106] The smoothing circuit 37 is configured to smooth the voltage rectified by the rectifier circuit 36. The smoothing circuit 37 has a capacitor 38. One end of the capacitor 38 is connected to the voltage line L21, and the other end is connected to the reference voltage line L22.

[0107] Figure 11 One example of the structure of the windings of the substrate 200 of the transformer 20B is shown. In Figure 11 the winding 21 is shown by a solid line, and the windings 26, 27 are shown by broken lines. The structures of the wiring layers LA2, LA3 are the same as in the case of the above-described embodiment. Figure 3

[0108] The windings 26, 27 are provided on the wiring layers LA1, LA4. On the substrate 200, through-holes TH21 to TH24 are provided which connect the wiring of the wiring layer LA1 and the wiring of the wiring layer LA4.

[0109] The winding 26 is configured so as to include the through-holes TH21, TH22, and is connected to the terminals T6, T7. The winding 26 is wound around the legs 112, 115. Specifically, the winding 26 is wound 2 turns in the clockwise direction on the leg 112 and 2 turns in the counterclockwise direction on the leg 115 in the direction from the terminal T6 toward the terminal T7.

[0110] The winding 27 is configured so as to include the through-holes TH23, TH24, and is connected to the terminals T8, T9. The winding 27 is wound around the legs 113, 114. Specifically, the winding 27 is wound 2 turns in the clockwise direction on the leg 113 and 2 turns in the counterclockwise direction on the leg 114 in the direction from the terminal T8 toward the terminal T9.

[0111] Figure 12 One example of the switching operation of the switching circuit 32 is shown.

[0112] ​In this example, at time t10, gate signals G2 and G3 transition from high to low. Consequently, transistors Q2 and Q3 are both turned off.

[0113] At time t11, gate signals G1 and G4 transition from low to high. This turns transistors Q1 and Q4 on. During the period from t11 to t12, transistors Q1 and Q4 remain on, while transistors Q2 and Q3 remain off. Then, at time t12, gate signals G1 and G4 transition from high to low. This turns transistors Q1 and Q4 off.

[0114] At time t13, gate signals G2 and G3 transition from low to high. This turns transistors Q2 and Q3 on. During the period from t13 to t14, transistors Q1 and Q4 remain off, while transistors Q2 and Q3 remain on. Furthermore, at time t14, gate signals G2 and G3 transition from high to low. This turns transistors Q2 and Q3 off.

[0115] At time t15, gate signals G1 and G4 transition from low to high. Consequently, transistors Q1 and Q4 become turned on.

[0116] Figure 13A ,13B indicates the operation of the power conversion device 1B, Figure 13A This represents the action at a certain time tA during the period t11 to t12. Figure 13B This represents the action of time tB during the period from time t13 to t14.

[0117] During the period from time t11 to t12, such as Figure 12 As shown, transistors Q1 and Q4 are in the ON state, and transistors Q2 and Q3 are in the OFF state. At this time, in the rectifier circuit 36, transistors Q5 and Q8 become ON according to gate signals G5 and G8, and transistors Q6 and Q7 become OFF according to gate signals G6 and G7. Therefore, at a certain time tA during the period t11 to t12, as... Figure 13A As shown, in the primary circuit, current IA1 flows sequentially through transistor Q1, capacitor 15, terminal T1, winding 21, terminal T2, and transistor Q4. Corresponding to this current IA1, in the secondary circuit, current IA2 flows sequentially through windings 26 and 27, terminals T6 and T8, transistor Q5, capacitor 38, load LD, transistor Q8, and terminals T7 and T9.

[0118] During the period from time t13 to t14, such as Figure 12As shown, the transistors Q1, Q4 are in the off state, and the transistors Q2, Q3 are in the on state. At this time, in the rectifier circuit 36, the transistors Q5, Q8 are in the off state according to the gate signals G5, G8, and the transistors Q6, Q7 are in the on state according to the gate signals G6, G7. Thus, at a certain time tB during the period from time t13 to time t14, as shown in FIG. 7, the current IB1 flows through the transistors Q3, the terminal T2, the winding 21, the terminal T1, the capacitor 15, and the transistor Q2 in this order in the primary-side circuit. In correspondence with the current IB1, the current IB2 flows through the windings 26, 27, the terminals T7, T9, the transistor Q7, the capacitor 38, and the load LD, the transistor Q6, the terminals T6, T8 in this order in the secondary-side circuit. Figure 13B As shown, in the primary-side circuit, the current IB1 flows through the transistors Q3, the terminal T2, the winding 21, the terminal T1, the capacitor 15, and the transistor Q2 in this order. In correspondence with the current IB1, in the secondary-side circuit, the current IB2 flows through the windings 26, 27, the terminals T7, T9, the transistor Q7, the capacitor 38, and the load LD, the transistor Q6, the terminals T6, T8 in this order.

[0119] The power conversion device 1B performs the above-described operation repeatedly, and thus steps up and outputs the direct-current electric power supplied from the direct-current power supply PDC. The power conversion device 1B controls the operation of the transistors Q1 to Q4 using the PWM, and thus makes the output voltage constant.

[0120] In the present example, although the direct-current power supply PDC is connected to the terminals T11, T12, and the load LD is connected to the terminals T21, T22, the present application is not limited to this. As an alternative, the direct-current power supply PDC can be connected to the terminals T21, T22, and the load LD can be connected to the terminals T11, T12. In this case, the power conversion device 1B operates the transistors Q5 to Q8 as a switching circuit, and operates the transistors Q1 to Q4 as a rectifier circuit, and thus can step up and output the direct-current electric power supplied from the direct-current power supply PDC.

[0121] In the present example, although the winding 26A, 26B is connected in parallel with the winding 27A, 27B as shown, the present application is not limited to this. For example, the terminals T7, T8 can be omitted, and the four windings 26A, 26B, 27A, 27B can be connected in series. In this case, the secondary-side winding constitutes one winding. Figure 10

[0122] [Modified Example 1-3]

[0123] In the above-described embodiment, although the winding 21 including the resonance coil is connected to the primary-side circuit of the power conversion device 1, the present application is not limited to this. As an alternative, for example, as shown in FIG. 11, the winding 21 including the resonance coil can be connected to the secondary-side circuit of the power conversion device 1. In this case, the winding 21 including the resonance coil is connected to the terminals T6, T8 of the power conversion device 1, and the winding 21 including the resonance coil is connected to the terminals T7, T9 of the power conversion device 1. Figure 14 ​The illustrated power conversion device 1C has the winding 21 connected to the secondary side circuit. The power conversion device 1C is provided with the capacitor 11, the switching circuit 32, the transformer 20B, the capacitor 35, the rectifier circuit 36, and the smoothing circuit 37. The terminals T6, T8 of the transformer 20B are connected to the node N1 of the switching circuit 32, and the terminals T7, T9 of the transformer 20B are connected to the node N2 of the switching circuit 32. The terminal T1 of the transformer 20B is connected to one end of the capacitor 35. The terminal T2 of the transformer 20B is connected to the node N4 of the rectifier circuit 36. One end of the capacitor 35 is connected to the terminal T1 of the transformer 20B, and the other end is connected to the node N3 of the rectifier circuit 36.

[0124] [Modified example 1-4]

[0125] The transformer 20 of the above-described embodiment can further have a heat sink. Hereinafter, the transformer 20D of the present modified example will be described in detail. The transformer 20D has a magnetic core 100D, a substrate 200, and a heat sink 130.

[0126] Figure 15 One configuration example of the transformer 20D is shown, (A) shows the magnetic core 100D, and (B) shows the heat sink 130. In Figure 15 In (B) of FIG. 10, a cross-sectional view of the heat sink 130 in the direction of the III-III arrow is also described.

[0127] The base portions 101, 102 of the magnetic core 100D each have an opening portion 121, 122. The opening portion 121 is provided between the leg portion 111 and the leg portion 112 and has a substantially rectangular shape. The opening portion 122 is provided between the leg portion 111 and the leg portion 113 and has a substantially rectangular shape. In the present example, the opening portions 121, 122 of the base portion 102 are respectively fitted with the protruding portions 141, 142 (described later) of the heat sink 130.

[0128] The heat sink 130 is a heat dissipation member made of a metal material having high thermal conductivity, such as aluminum. The heat sink 130 has six protruding portions 132 to 135, 141, and 142 in this example. The protruding portions 132 to 135, 141, and 142 have a substantially rectangular shape, and have a height in the Z direction that is substantially the same as the thickness of the base portion 102, for example. The base portion 102 of the magnetic core 100D is fitted into a region surrounded by the protruding portions 132 to 135 of the heat sink 130. The protruding portion 141 is fitted into the opening portion 121 of the base portion 102, and the protruding portion 142 is fitted into the opening portion 122 of the base portion 102. Thus, the protruding portions 132 to 135, 141, and 142 of the heat sink 130 are thermally connected to the substrate 200 of the magnetic core 100D. Note that an insulating heat sink can be provided on the protruding portions 132 to 135, 141, and 142 of the heat sink 130, and the substrate 200 of the magnetic core 100D can be thermally connected via the insulating heat sink.

[0129] Here, the magnetic core 100D corresponds to one specific example of the "magnetic core" of the present disclosure. The opening portion 121 corresponds to one specific example of the "first opening portion" of the present disclosure. The opening portion 122 corresponds to one specific example of the "second opening portion" of the present disclosure. The protruding portion 141 corresponds to one specific example of the "first protruding portion" of the present disclosure. The protruding portion 142 corresponds to one specific example of the "second protruding portion" of the present disclosure.

[0130] As such, in the transformer 20D, because the opening portions 121 and 122 are provided on the base portions 101 and 102 of the magnetic core 100D, heat dissipation can be performed not only from the peripheral portions of the magnetic core 100D but also from the vicinity of the central portion of the magnetic core 100D, and thus the heat dissipation performance can be improved. In particular, in the transformer 20D, because the opening portions 121 and 122 are provided in regions in which the magnetic flux density is sufficiently low, as shown in FIGS. 7A and 7B, the magnetic characteristics can be maintained while the heat dissipation performance is effectively improved. Figure 7A

[0131] In addition, in the transformer 20D, because the heat sink 130 is provided, the heat dissipation performance can be further improved.

[0132] Note that in the transformer 20D, although the heat sink 130 is attached to the base portion 102, the present disclosure is not limited thereto, and the heat sink 130 can be attached to the base portion 101, or the heat sink 130 can be attached to both of the base portions 101 and 102. In addition, although the opening portions 121 and 122 are provided on both of the base portions 101 and 102, the present disclosure is not limited thereto, and the opening portions 121 and 122 can be provided on only one of the base portions 101 and 102.

[0133] [Modified Example 1-5]

[0134] ​For example, an air gap, a spacer gap, a gap sheet, or the like can be provided in the magnetic coupling portion of some or all of the feet 111 to 115.

[0135] [Other modifications]

[0136] In addition, two or more of these modifications can be combined.

[0137] [Second Embodiment]

[0138] Next, the power conversion device 2 of the second embodiment will be described. In the present embodiment, the structure of the transformer is different from that of the first embodiment described above. Further, the same reference numerals are attached to the substantially same structural portions as those of the power conversion device 1 of the first embodiment, and the description thereof will be appropriately omitted.

[0139] Figure 16 One configuration example of the power conversion device 2 is shown. The power conversion device 2 is provided with a transformer 40. The transformer 40 has a winding 41.

[0140] One end of the winding 41 is connected to a terminal T1, and the other end is connected to a terminal T2. The winding 41 includes windings 41A, 41B, 41C, 41D, 41E, and 41F. The windings 41A and 41B are resonance coils, and the windings 41C to 41F are primary-side windings of the transformer. The windings 41A to 41F are connected in series. The winding 41A is connected to the terminal T1, and the winding 41F is connected to the terminal T2.

[0141] Figure 17 One configuration example of the transformer 40 is shown. In Figure 17 In the transformer 40, a cross-sectional view in the direction of the IV-IV arrow and a cross-sectional view in the direction of the V-V arrow are also described. The transformer 40 has a magnetic core 300 and a substrate 400.

[0142] The magnetic core 300 has base portions 301 and 302 and six feet 311 to 316. The base portions 301 and 302 are opposed in the Z direction. The base portions 301 and 302 have a substantially rectangular shape in the XY plane along the X direction. The feet 311 to 316 are arranged in the facing surfaces of the two base portions 301 and 302, and are provided so as to magnetically couple the two base portions 301 and 302. The feet 311, 312, and 313 are arranged in series side by side in the X direction, and the feet 314, 315, and 316 are arranged in series side by side in the X direction. The feet 311 and 314 are arranged in series side by side in the Y direction, the feet 312 and 315 are arranged in series side by side in the Y direction, and the feet 313 and 316 are arranged in series side by side in the Y direction. In the XY plane, the cross-sectional area of the feet 312 and 315 is larger than that of the feet 311, 313, 314, and 316.

[0143] The substrate 400 is a multilayer substrate (in this example, a four-layer substrate). Through holes are provided on the substrate 400 at positions corresponding to the feet 311-316 of the magnetic core 300, and the substrate 400 is sandwiched between the base portions 301 and 302 of the magnetic core 300. Windings 41 and 22A, 23A, 22B, 23B, 22C, 23C, 22D, and 23D are provided on the substrate 400.

[0144] Figure 18 This illustrates a structural example of the windings on substrate 400. Figure 18 In the diagram, solid lines represent winding 41, and dashed lines represent windings 22A, 23A, 22B, 23B, 22C, 23C, 22D, and 23D.

[0145] Windings 41 (windings 41A, 41B, 41C, 41D, 41E, 41F) are provided on wiring layers LA2 and LA3. Through holes TH31 to TH37 connecting the wiring of wiring layer LA2 and wiring layer LA3 are provided on the substrate 400. The windings 41 are configured to include these through holes TH31 to TH37 and are connected to terminals T1 and T2. The windings 41 are wound around six feet 311 to 316. Specifically, the windings 41 are wound clockwise around feet 311, 313, and 315 from terminal T1 towards terminal T2, and counterclockwise around feet 312, 314, and 316. The portion of winding 41 wound on feet 311 and 316 corresponds to windings 41A and 41B of the resonant coil, and the portion wound on feet 312 to 315 corresponds to windings 41C to 41F of the primary winding of the transformer.

[0146] On wiring layer LA1, windings 22A, 22B, 22C, and 22D are provided. Winding 22A is wound once counter-clockwise around foot 314 from terminal T3A to terminal T4A. Winding 22B is wound once counter-clockwise around foot 312 from terminal T3B to terminal T4B. Winding 22C is wound once clockwise around foot 313 from terminal T3C to terminal T4C. Winding 22D is wound once clockwise around foot 315 from terminal T3D to terminal T4D.

[0147] On wiring layer LA4, windings 23A, 23B, 23C, and 23D are provided. Winding 23A is wound once clockwise around foot 314 from terminal T5A towards terminal T4A. Winding 23B is wound once clockwise around foot 312 from terminal T5B towards terminal T4B. Winding 23C is wound once counterclockwise around foot 313 from terminal T5C towards terminal T4C. Winding 23D is wound once counterclockwise around foot 315 from terminal T5D towards terminal T4D.

[0148] Here, transformer 40 corresponds to a specific example of the "magnetic component" of this disclosure. Magnetic core 300 corresponds to a specific example of the "magnetic core" of this disclosure. Foot 311 corresponds to a specific example of the "first foot" of this disclosure. Foot 312 corresponds to a specific example of the "second foot" of this disclosure. Foot 313 corresponds to a specific example of the "third foot" of this disclosure. Foot 314 corresponds to a specific example of the "fourth foot" of this disclosure. Foot 315 corresponds to a specific example of the "fifth foot" of this disclosure. Foot 316 corresponds to a specific example of the "sixth foot" of this disclosure. Winding 41 corresponds to a specific example of the "first winding" of this disclosure. Transformer 40 corresponds to a specific example of the "transformer" of this disclosure.

[0149] The switching circuit 12 of the power conversion device 2 operates in the same manner as in the first embodiment described above. Figure 4 (5A, 5B) The same action.

[0150] Figure 19A ,19B indicates the direction of the magnetic flux at feet 311-316 of magnetic core 300. Figure 19A This indicates the direction of the magnetic flux at time tA. Figure 19B This indicates the direction of the magnetic flux at time tB. Figure 20A ,20B indicates the direction of the magnetic flux in the base portion 301 of the magnetic core 300. Figure 20A This indicates the direction of the magnetic flux at time tA. Figure 20B This indicates the direction of the magnetic flux at time tB.

[0151] Compared with the first embodiment described above ( Figure 4 Similarly, during the period from t1 to t2, transistor 13 is in the on state and transistor 14 is in the off state. Therefore, at a certain time tA during the period from t1 to t2, as... Figure 5AAs shown, in the primary side circuit, the current IA1 flows through the transistor 13, the capacitor 15, the terminal T1, the winding 41, and the terminal T2 in this order. In correspondence with this current IA1, in the secondary side circuit of the rectifying circuit 16A and the smoothing circuit 17A, for example, the current IA2 flows through the winding 23A, the terminal T4A, the capacitor 18, and the load LD, the diode D2, and the terminal T5A in this order.

[0152] As shown, in the winding 41, the current IA1 flows from the terminal T1 toward the terminal T2, in the transformer 40, as shown in Figure 19A magnetic fluxes are generated in the legs 311 to 316. Since the winding 41 is wound in the clockwise direction on the legs 311, 313, 315 and in the counterclockwise direction on the legs 312, 314, 316, respectively, the directions of the magnetic fluxes of the legs 311, 313, 315 are directions opposite to the Z direction, and the directions of the magnetic fluxes of the legs 312, 314, 316 are the Z direction. In the base 302, as shown in Figure 20A magnetic fluxes are generated in the legs 311 to 316. Since the winding 41 is wound in the clockwise direction on the legs 311, 313, 315 and in the counterclockwise direction on the legs 312, 314, 316, respectively, the directions of the magnetic fluxes of the legs 311, 313, 315 are directions opposite to the Z direction, and the directions of the magnetic fluxes of the legs 312, 314, 316 are the Z direction. In the base 302, as shown in Figure 20A

[0153] As shown in Figs. 5A and 5B, at the time t3 to t4, the transistor 13 is in the off state, and the transistor 14 is in the on state. Thus, at a certain time tB during the time t3 to t4, as shown in Figure 4 ,5B, at the time t3 to t4, the transistor 13 is in the off state, and the transistor 14 is in the on state. Thus, at a certain time tB during the time t3 to t4, as shown in Figure 5B As shown, in the primary side circuit, the current IB1 flows through the capacitor 15, the transistor 14, the terminal T2, the winding 41, and the terminal T1 in this order. In correspondence with this current IB1, in the secondary side circuit of the rectifying circuit 16A and the smoothing circuit 17A, for example, the current IA2 flows through the winding 22A, the terminal T4A, the capacitor 18, and the load LD, the diode D2, and the terminal T3A in this order.

[0154] As shown, in the winding 41, the current IB1 flows from the terminal T2 toward the terminal T1, in the transformer 40, as shown in Figure 19B magnetic fluxes are generated in the legs 311 to 316. Since the winding 41 is wound in the clockwise direction on the legs 311, 313, 315 and in the counterclockwise direction on the legs 312, 314, 316, respectively, the directions of the magnetic fluxes of the legs 311, 313, 315 are directions opposite to the Z direction, and the directions of the magnetic fluxes of the legs 312, 314, 316 are the Z direction. In the base 302, as shown in Figure 20B ​As shown, magnetic flux is generated from the leg 312 toward the legs 311, 313, 315, magnetic flux is generated from the leg 314 toward the legs 311, 315, and magnetic flux is generated from the leg 316 toward the legs 313, 315. The direction of the magnetic flux of the base 301 is opposite to the direction of the magnetic flux of the base 302. Figure 20B

[0155] The power conversion device 2 performs voltage conversion on the direct-current electric power supplied from the direct-current power source PDC and outputs the same by repeatedly performing such an operation. The power conversion device 2 controls the operation of the transistors 13, 14 by using PWM, thereby making the output voltage constant.

[0156] In the power conversion device 2, six legs 311 to 316 are provided, and the legs 311, 312, 313 are provided in series in the X direction, the legs 314, 315, 316 are provided in series in the X direction, the legs 311, 314 are provided in series in the Y direction, the legs 312, 315 are provided in series in the Y direction, and the legs 313, 316 are provided in series in the Y direction. In addition, in the direction from the terminal T1 toward the terminal T2, the winding 41 is wound on the legs 311, 313, 315 in the first winding direction, and the winding 41 is wound on the legs 312, 314, 316 in the second winding direction. Thus, in the transformer 40, as shown in FIG. 20B, magnetic flux in a first direction is generated in the legs 311, 313, 315, and magnetic flux in a second direction is generated in the legs 312, 314, 316. Then, in the bases 301, 302, the magnetic flux is dispersed. As such, because the magnetic flux density of the bases 301, 302 can be reduced by dispersing the magnetic flux in the bases 301, 302, the height of the bases 301, 302 in the Z direction can be reduced. In addition, because six legs 311 to 316 are provided as such, the number of turns of the winding 41 of each of the legs 311 to 316 can be suppressed, for example, the number of layers of the substrate 400 can be reduced, thereby the height of the legs 311 to 316 in the Z direction can be reduced. As a result, in the power conversion device 2, the size of the transformer 40 can be reduced. Figure 20A In the power conversion device 2, because the cross-sectional area of the legs 312, 315 is made larger than the cross-sectional area of the legs 311, 313, 314, 316, the magnetic flux density of the legs 312, 315 can be reduced. That is, as shown in FIG. 20B, the magnetic flux density of the legs 312, 315 is lower than the magnetic flux density of the legs 311, 313, 314, 316.

[0157] Figure 20A ​​,20B, for example, because the magnetic path of the two feet 312, 314 is formed in the foot 311, the magnetic flux is strong in the foot 312, in which the magnetic path of the three feet 311, 313, 315 is formed. The same is true for the foot 315. In the power conversion device 2, because the cross-sectional area of the feet 312, 315 is made larger than that of the feet 311, 313, 314, 316, the magnetic flux density of the feet 312, 315 can be reduced.

[0158] In addition, in the power conversion device 2, the winding 41 is wound around the six feet 311 to 316, and the windings 22A, 23A, 22B, 23B, 22C, 23C, 22D, 23D are wound around the four feet 312 to 315 other than the feet 311, 316. Thereby, the portion of the winding 41 wound around the feet 311, 316 can function as a resonance coil. Thereby, because the resonance coil and the transformer can be combined in the transformer 40, the size of the power conversion device 2 can be reduced compared to the case where the resonance coil and the transformer are separately provided.

[0159] In addition, in the power conversion device 2, because the resonance coil can be formed by winding the winding 41 around the two feet 311, 316, the inductance of the resonance coil can be increased, and thus the power conversion device 2 can operate in a wider range of input voltage. In addition, because the resonance coil is wound around the feet 311, 316 located at diagonal positions, in the power conversion device 2, for example, at the time t6, t7 in FIG. 20B, when the current II on the primary side is the largest, the large magnetic flux from the foot 311 wound with the primary-side winding only can be dispersed toward the foot 316 wound with the primary-side winding only through the base portion 301, for example, and returned to the foot 311 from the foot 316 through the base portion 302. Therefore, in the power conversion device 2, the large magnetic flux generated by the resonance coil when the current of the resonance coil is the largest can be dispersed, and the magnetic flux density can be reduced. In addition, for example, at the time to, t2 in FIG. 20B, when the exciting current Im is the largest, the magnetic flux of the transformer 40 is the largest. At this time, no current I2 flows on the secondary side, and the magnetic flux is generated in the six feet 311 to 316 by the current II on the primary side, as shown in FIG. 20B. The magnetic flux can be dispersed in the base portions 301, 302. As a result, the size of the transformer 40 can be effectively reduced. Figure 4 Figure 4 In addition, in the power conversion device 2, because the resonance coil can be formed by winding the winding 41 around the two feet 311, 316, the inductance of the resonance coil can be increased, and thus the power conversion device 2 can operate in a wider range of input voltage. In addition, because the resonance coil is wound around the feet 311, 316 located at diagonal positions, in the power conversion device 2, for example, at the time t6, t7 in FIG. 20B, when the current II on the primary side is the largest, the large magnetic flux from the foot 311 wound with the primary-side winding only can be dispersed toward the foot 316 wound with the primary-side winding only through the base portion 301, for example, and returned to the foot 311 from the foot 316 through the base portion 302. Therefore, in the power conversion device 2, the large magnetic flux generated by the resonance coil when the current of the resonance coil is the largest can be dispersed, and the magnetic flux density can be reduced. In addition, for example, at the time to, t2 in FIG. 20B, when the exciting current Im is the largest, the magnetic flux of the transformer 40 is the largest. At this time, no current I2 flows on the secondary side, and the magnetic flux is generated in the six feet 311 to 316 by the current II on the primary side, as shown in FIG. 20B. The magnetic flux can be dispersed in the base portions 301, 302. As a result, the size of the transformer 40 can be effectively reduced. Figure 20A

[0160] ​​In the present embodiment, as described above, six legs 311 to 316 are provided, and the legs 311, 312, 313 are arranged side by side in the X direction, the legs 314, 315, 316 are arranged side by side in the X direction, the legs 311, 314 are arranged side by side in the Y direction, the legs 312, 315 are arranged side by side in the Y direction, and the legs 313, 316 are arranged side by side in the Y direction. In addition, in the direction from the terminal T1 toward the terminal T2, the winding 41 is wound on the legs 311, 313, 315 in the first winding direction, and the winding 41 is wound on the legs 312, 314, 316 in the second winding direction. Thus, the size of the transformer can be reduced.

[0161] In the present embodiment, since the winding 41 is wound on the six legs 311 to 316, and the windings 22A, 23A, 22B, 23B, 22C, 23C, 22D, 23D are wound on the four legs 312 to 315 other than the legs 311, 316, the size of the power conversion device can be reduced, and the power conversion device can operate in a large input voltage range.

[0162] [Modified Example 2-1]

[0163] In the power conversion device 2 of the above-described embodiment, the modified examples 1-1 to 1-3 of the first embodiment can also be applied.

[0164] [Modified Example 2-2]

[0165] The transformer 40 of the above-described embodiment can also further have a heat sink, as in the modified example 1-4 of the first embodiment. Hereinafter, the transformer 40D of the present modified example will be described in detail. The transformer 40D has a magnetic core 300D, a substrate 400, and a heat sink 330.

[0166] Figure 21 FIG. 17 shows one configuration example of the transformer 40D, and (A) shows the magnetic core 300D, and (B) shows the heat sink 330. InIn (B) of FIG. 17, a cross-sectional view of the heat sink 330 in the direction of the VI-VI arrow is also described. Figure 21

[0167] The base portions 301, 302 of the magnetic core 300D each have an opening portion 321, 322. The opening portion 321 is provided between the four legs 311, 312, 314, 315, and has a substantially rectangular shape. The opening portion 322 is provided between the legs 312, 313, 315, 316, and has a substantially rectangular shape. In this example, the opening portions 321, 322 of the base portion 302 are respectively fitted with the protruding portions 341, 342 (described later) of the heat sink 330.

[0168] The heat sink 330 has six protruding portions 332 to 335, 341, 342 in this example. The protruding portions 332 to 335, 341, 342 have a substantially rectangular shape, and the height in the Z direction is substantially the same as the thickness of the base portion 302, for example. The base portion 302 of the magnetic core 300D is fitted in the area surrounded by the protruding portions 332 to 335 of the heat sink 330. The protruding portion 341 is fitted in the opening portion 321 of the base portion 302, and the protruding portion 342 is fitted in the opening portion 322 of the base portion 302. Thus, the protruding portions 332 to 335, 341, 342 of the heat sink 330 are thermally connected to the substrate 400 of the magnetic core 300D.

[0169] Here, the magnetic core 300D corresponds to one specific example of the "magnetic core" of the present disclosure. The opening portion 321 corresponds to one specific example of the "first opening portion" of the present disclosure. The opening portion 322 corresponds to one specific example of the "second opening portion" of the present disclosure. The protruding portion 341 corresponds to one specific example of the "first protruding portion" of the present disclosure. The protruding portion 342 corresponds to one specific example of the "second protruding portion" of the present disclosure.

[0170] [Modified Example 2-3]

[0171] For example, an air gap, a spacer gap, a gap sheet, or the like can be provided in the magnetic coupling portion of some or all of the foot portions 311 to 316.

[0172] [Other Modified Examples]

[0173] In addition, two or more of these modified examples can be combined.

[0174] The above describes the present application by citing the embodiments and the modified examples, but the present application is not limited to these embodiments and the like, and various changes can be made.

[0175] For example, in the above-described embodiments and the like, although the direct-current electric power supplied from the direct-current power supply PDC is converted, and the converted direct-current electric power is supplied to the load LD, the present application is not limited thereto. As an alternative, as shown in a power conversion system 90, a battery 91, 92 can be provided, and the power conversion device 1 can convert the direct-current electric power supplied from the battery 91, and supply the converted direct-current electric power to the battery 92. Figure 22

[0176] This application contains subject matter related to that disclosed in Japanese Priority Patent Application JP 2020-052502 filed in the Japan Patent Office on March 24, 2020, the entire content of which is incorporated herein by reference in its entirety.​

Claims

1. A magnetic component comprising: a core having two base portions facing each other and five leg portions including a first leg portion, a second leg portion, a third leg portion, a fourth leg portion, and a fifth leg portion disposed in facing surfaces of the two base portions and magnetically coupling the two base portions, the second leg portion and the third leg portion being disposed to sandwich the first leg portion in a first direction, the fourth leg portion and the fifth leg portion being disposed to sandwich the first leg portion in a second direction; a first terminal and a second terminal; a first winding wound in a first winding direction on the first leg portion, the second leg portion, and the third leg portion in a direction from the first terminal toward the second terminal, and wound in a second winding direction on the fourth leg portion and the fifth leg portion; and one or more second windings wound on four of the five leg portions other than the first leg portion.

2. The magnetic component according to claim 1, wherein a cross-sectional area of the fourth leg portion and a cross-sectional area of the fifth leg portion are larger than a cross-sectional area of the second leg portion and a cross-sectional area of the third leg portion.

3. The magnetic component according to claim 1 or claim 2, wherein widths of the fourth leg portion and the fifth leg portion in the first direction are wider than widths of the second leg portion and the third leg portion in the second direction.

4. The magnetic component according to claim 1 or claim 2, wherein a width of the first leg portion in the first direction is wider than widths of the second leg portion and the third leg portion in the second direction.

5. The magnetic component according to claim 1 or claim 2, further comprising a heat sink, the two base portions having a first base portion and a second base portion, the first base portion having a first opening portion disposed between the first leg portion and the second leg portion and a second opening portion disposed between the first leg portion and the third leg portion, the heat sink having a first protrusion portion disposed at a position corresponding to the first opening portion of the first base portion and a second protrusion portion disposed at a position corresponding to the second opening portion of the first base portion.

6. A magnetic component comprising: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ A magnetic core having two base portions facing each other and six leg portions including a first leg portion, a second leg portion, a third leg portion, a fourth leg portion, a fifth leg portion, and a sixth leg portion disposed in facing surfaces of the two base portions and magnetically coupling the two base portions, the first leg portion, the second leg portion, and the third leg portion being arranged side by side in a first direction, the fourth leg portion, the fifth leg portion, and the sixth leg portion being arranged side by side in the first direction, the first leg portion and the fourth leg portion being arranged side by side in a second direction, the second leg portion and the fifth leg portion being arranged side by side in the second direction, and the third leg portion and the sixth leg portion being arranged side by side in the second direction; a first terminal and a second terminal; a first winding wound on the first leg portion, the third leg portion, and the fifth leg portion in a first winding direction in a direction from the first terminal toward the second terminal, and wound on the second leg portion, the fourth leg portion, and the sixth leg portion in a second winding direction; and one or more second windings wound on four of the six leg portions other than the first leg portion and the sixth leg portion.

7. The magnetic component according to claim 6, wherein a cross-sectional area of the second leg portion and a cross-sectional area of the fifth leg portion are larger than a cross-sectional area of the first leg portion, a cross-sectional area of the third leg portion, a cross-sectional area of the fourth leg portion, and a cross-sectional area of the sixth leg portion.

8. The magnetic component according to claim 6 or claim 7, further comprising a heat sink, the two base portions include a first base portion and a second base portion, the first base portion has a first opening portion disposed between the first leg portion, the second leg portion, the fourth leg portion, and the fifth leg portion, and a second opening portion disposed between the second leg portion, the third leg portion, the fifth leg portion, and the sixth leg portion, the heat sink has a first protrusion portion and a second protrusion portion mounted on the first base portion, the first protrusion portion being disposed at a position corresponding to the first opening portion of the first base portion, and the second protrusion portion being disposed at a position corresponding to the second opening portion of the first base portion.

9. A power conversion device comprising: the magnetic component according to any one of claims 1 to 8, a switching circuit connected to at least one of the first terminal and the second terminal of the magnetic component and having one or more switching elements; a rectifying circuit connected to the one or more second windings of the magnetic component; and a smoothing circuit connected to the rectifying circuit.

10. A power conversion device comprising: the magnetic component according to any one of claims 1 to 8, a switching circuit connected to the one or more second windings of the magnetic component and having one or more switching elements; a rectifying circuit connected to the first terminal and the second terminal of the magnetic component; and a smoothing circuit connected to the rectifying circuit. ​ ​ A smoothing circuit connected to the rectifying circuit.

11. A power conversion system comprising: the power conversion device according to claim 9 or claim 10; a first battery connected to the switching circuit of the power conversion device; and a second battery connected to the smoothing circuit of the power conversion device.

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