Cooling unit of rectifying element module

Abstract

The invention provides a cooling unit of a rectifying element module. A cooling unit for a rectifying element module is provided with a rectifying element module (10), a substrate (20), a first conductive cooling section (30), a second conductive cooling section (40), and a conductive cooling promoting section (50) that is electrically connected to one of the first conductive cooling section and the second conductive cooling section and insulatively connected to the other of the first conductive cooling section and the second conductive cooling section. A part of the first circuit path (60) is configured from a first through-current path (61) penetrating the substrate (20) from the substrate front surface (21) to the substrate back surface (22), and a part of the second current path (70) is configured from a second through-current path (71) penetrating the substrate (20) from the substrate front surface (21) to the substrate back surface (22).

Description

Technical Field

[0001] The present invention relates to a cooling unit for a rectifier element module. Background Art

[0002] For example, a power conversion device includes a primary circuit that receives an input voltage, a secondary circuit that outputs an output voltage, and a converter magnetically connecting the primary and secondary circuits. The secondary circuit includes a rectifier circuit that rectifies the voltage waveform generated in the converter's secondary winding. High current flows through this rectifier circuit, generating heat. This heat can damage components that make up the rectifier circuit, necessitating cooling of the rectifier circuit.

[0003] Patent document 1 discloses an electric power conversion device comprising: a converter, a rectifier element constituting a rectifier circuit on the secondary side of the converter, a choke coil constituting a smoothing circuit on the secondary side of the converter, and a housing provided with the choke coil and having a cooling portion. A water channel serving as a cooling portion of the housing is formed at the bottom, and the housing has a pair of upright portions arranged upright relative to the water channel. A metal substrate is arranged along the outer surface of each upright portion while the choke coil is clamped inside the pair of upright portions. Rectifier elements are respectively arranged on these metal substrates. The heat generated in the rectifier element and the metal substrate is dissipated to the water channel via each upright portion, thereby cooling the rectifier element and the metal substrate. Prior art literature Patent Literature

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2016-144238 Summary of the Invention Problems to be solved by the invention

[0005] However, while the structure of Patent Document 1 can dissipate heat generated by the rectifier element and the metal substrate, it cannot suppress heat generation within the metal substrate. Specifically, since the high current flowing through the rectifier element is extracted to the outside via the metal substrate, a high current flows through the metal substrate. This increases the heat generated by the metal substrate, potentially damaging the rectifier element. Therefore, improvements to the cooling structure of the rectifier circuit are sought.

[0006] Therefore, a main object of the present invention is to provide a cooling unit for a rectifier element module. Means for solving problems

[0007] The cooling unit of the rectifier element module involved in the present invention comprises: a rectifier element module having an element body in which a rectifier element having a first element terminal and a second element terminal is arranged, a first module terminal electrically connected to the first element terminal, and a second module terminal electrically connected to the second element terminal; a substrate formed in a plate shape and having a substrate surface and a substrate back surface, and the rectifier element module is arranged on the substrate surface side; a first conductive cooling portion for electrically connecting a first external component arranged outside the cooling unit relative to the rectifier element module and the first module terminal, and mainly cooling heat caused by a first current passing through the first element terminal; a second conductive cooling portion for electrically connecting a first external component arranged outside the cooling unit relative to the rectifier element module and the first module terminal, and mainly cooling heat caused by a first current passing through the first element terminal; and a second conductive cooling portion for electrically connecting a first external component arranged outside the cooling unit relative to the rectifier element module and the first module terminal. An external second external component is electrically connected to the second module terminal, and mainly cools the heat caused by the second current passing through the second element terminal; and a conductive cooling promotion part has a configuration surface for configuring the first conductive cooling part and the second conductive cooling part, is electrically connected to one of the first conductive cooling part and the second conductive cooling part via the configuration surface, and is insulated from the other, and is used to promote the cooling of the first conductive cooling part and the second conductive cooling part. A part of the first circuit path of the first current that reaches the first external component from the first element terminal via the first module terminal and the first conductive cooling part is composed of a first through-current path that penetrates the substrate from the surface of the substrate to the back of the substrate.

[0008] According to the above configuration, it is possible to provide a cooling unit for cooling the substrate and the rectifying element module. Effects of the Invention

[0009] According to the present invention, a cooling unit for a rectifier element module can be provided.

[0010] The above-mentioned object, other objects, features and advantages of the present invention will become more apparent from the following description of the embodiment of the invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a side view of a cooling unit for the rectifier element module according to the first embodiment of the present invention. Figure 2 It is a plan view of a cooling unit of a rectifier element module according to the first embodiment of the present invention. Figure 3 This is a circuit diagram of a power conversion device having a synchronous rectification circuit. Figure 4 (a) is a top perspective view of the rectifier element module, and (b) is a back perspective view of (a). Figure 5Yes Figure 1 A current path diagram showing the flow of current in the cooling unit of the rectifier element module. Figure 6A This is a side view of a cooling unit for a rectifier element module according to another aspect 1 of the first embodiment of the present invention. Figure 6B This is a side view of a cooling unit for a rectifier element module according to another aspect 2 of the first embodiment of the present invention. Figure 7 It is a side view of a cooling unit of a rectifier element module according to Embodiment 2 of the present invention. Figure 8 It is a plan view of a cooling unit of a rectifier element module according to Embodiment 2 of the present invention. Figure 9 (a) is a top perspective view of the rectifier element module, and (b) is a back perspective view of (a). Figure 10 Yes Figure 7 A current path diagram showing the flow of current in the cooling unit of the rectifier element module. Figure 11A It is a side view of a cooling unit of a rectifier element module according to another aspect 1 of the second embodiment of the present invention. Figure 11B This is a side view of a cooling unit for a rectifier element module according to another aspect 2 of the second embodiment of the present invention. Figure 11C This is a side view of a cooling unit for a rectifier element module according to another aspect 3 of the second embodiment of the present invention. Figure 12 This is a circuit diagram of a power conversion device having a synchronous rectification circuit of another configuration 1. Figure 13 This is a circuit diagram of a power conversion device having a synchronous rectification circuit of another configuration 2. Figure 14 This is a circuit diagram of a power conversion device having a synchronous rectification circuit of another configuration 3. Figure 15 This is a circuit diagram of a power conversion device having a synchronous rectification circuit of another configuration 4. Figure 16 This is a circuit diagram of a power conversion device having a rectifier circuit. DETAILED DESCRIPTION

[0012] 1. Implementation Method 1 (1) Configuration of the cooling unit for the rectifier element module The configuration of the cooling unit 100 for the rectifier element module according to the first embodiment of the present invention will be described below with reference to the drawings. Figure 1 This is a side view of a cooling unit for the rectifier element module according to the first embodiment of the present invention. Figure 2 It is a plan view of a cooling unit of a rectifier element module according to the first embodiment of the present invention.

[0013] The cooling unit 100 for the rectifier element module includes a rectifier element module 10, a substrate 20, a first conductive cooling unit 30, a second conductive cooling unit 40, and a cooling promotion unit 50. The rectifier element module 10 generates a rectified output voltage. The rectifier element module 10 is arranged on the substrate 20. The first conductive cooling unit and the second conductive cooling units 30 and 40 electrically transmit signals in the rectifier element module 10 and cool the rectifier element module 10 and the substrate 20. Figure 1 、 Figure 2 In the embodiment, the direction in which the first conductive cooling part 30 and the second conductive cooling part 40 are arranged is referred to as the x-direction. The direction perpendicular to the x-direction is referred to as the y-direction. The direction perpendicular to the x-direction and the y-direction is referred to as the z-direction, which is sometimes also referred to as the vertical direction, up, and down. In addition, the surface parallel to the xy plane is sometimes referred to as the horizontal plane, and the direction along the horizontal plane is sometimes referred to as the horizontal direction. In this embodiment, the substrate 20 extends in the horizontal direction. In addition, the surface perpendicular to the xy plane is sometimes referred to as the vertical plane. The following describes each part.

[0014] The rectifier module 10 includes rectifier elements for generating a rectified output voltage. The rectifier elements form a synchronous rectifier circuit. This synchronous rectifier circuit is used in the power converter 1. Figure 3 This is a circuit diagram of a power conversion device having a synchronous rectification circuit.

[0015] There are many kinds of power conversion devices using synchronous rectification circuits. As an example, a midpoint tapped power conversion device 1 is cited here as an example for explanation. Figure 3 As shown, power conversion device 1 includes converter 2, primary circuit 3, and secondary circuit 4. Primary circuit 3 generates an AC voltage from a DC voltage and supplies the AC voltage to primary winding 2b of converter 2. Current flowing through primary winding 2b generates a magnetic field, and electromagnetic induction of this magnetic field induces current in secondary windings 2c and 2d of converter 2 (an example of a second external component in this embodiment). Consequently, output voltages corresponding to the winding ratio are obtained from secondary windings 2c and 2d.

[0016] The converter 2 includes a core 2a, a primary winding 2b, and secondary windings 2c and 2d. The primary winding 2b is wound around the core 2a from the primary winding start end 2b1 to the primary winding end end 2b2. The secondary windings 2c and 2d are wound around the core 2a and include a first partial winding 2c and a second partial winding 2d. The first partial winding 2c is wound around the core 2a from the first partial winding start end 2c1 to the first partial winding end end 2c2. The second partial winding 2d is wound around the core 2a from the second partial winding start end 2d1 to the second partial winding end 2d2. Furthermore, the first partial winding end 2c2 and the second partial winding start end 2d1 are connected in series. The first partial winding start end 2c1 and the second partial winding end 2d2 are connected to the secondary-side output (-) line Vout(-) (an example of a first external component in this embodiment) via the secondary-side circuit 4. The connection between the first partial winding end 2c2 and the second partial winding start end 2d1 is commonly connected to the secondary-side output (+) line Vout(+). The output voltage induced in the first and second partial windings 2c, 2d is output from the secondary-side output (+) line Vout(+).

[0017] Primary-side circuit 3 is not limited to any circuit, as long as it can receive a DC voltage input from primary-side input (+) line Vin(+) and primary-side input (-) line Vin(-) and generate an AC voltage from the DC voltage. For example, primary-side circuit 3 may include multiple transistors that receive the DC voltage from primary-side input (+) line Vin(+) and primary-side input (-) line Vin(-). By switching the multiple transistors, primary-side circuit 3 can generate an AC voltage from the DC voltage.

[0018] The secondary circuit 4 rectifies the output voltage induced in the secondary windings 2c and 2d. The secondary circuit 4 includes first and second transistors Q1 and Q2 (an example of a rectifying element). The first transistor Q1 has a first gate terminal G1, a first source terminal S1 (an example of a first element terminal), and a first drain terminal D1 (an example of a second element terminal). Furthermore, the second transistor Q2 has a second gate terminal G2, a second source terminal S2 (an example of a first element terminal), and a second drain terminal D2 (an example of a second element terminal). A first gate signal g1 is input to the first gate terminal G1, and a second gate signal g2 is input to the second gate terminal G2. Furthermore, the first and second drain terminals D1 and D2 are connected to the secondary windings 2c and 2d (an example of a second external component in this embodiment). Specifically, the first drain terminal D1 is connected to the end of the second partial winding 2d2, and the second drain terminal D2 is connected to the start of the first partial winding 2c1. The first source terminal and the second source terminal S1 and S2 are commonly connected to the secondary-side output (-) line Vout(-).

[0019] In such a secondary side circuit 4, the first transistor Q1 and the second transistor Q2 perform switching operations based on the voltage difference applied to the first gate terminal, the second gate terminal G1, G2, the first source terminal S1, S2, the first drain terminal, the second drain terminal D1, D2. Figure 3 In this example, the first and second transistors Q1 and Q2 are alternately turned on and off. Consequently, the output voltage from the first winding section 2c and the output voltage from the second winding section 2d are alternately output from the secondary-side output (+) line Vout(+). As a result, a rectified output voltage is output from the secondary-side output (+) line Vout(+). In this embodiment, the first and second transistors Q1 and Q2 form a synchronous rectification circuit.

[0020] Furthermore, the secondary side circuit 4 may include a rectification-related circuit such as a smoothing circuit in addition to the synchronous rectification circuit (an example of a rectification circuit).

[0021] In this embodiment, the transistor is, for example, a MOSFET transistor (Metal Oxide Semiconductor Field Effect Transistor). However, an IGBT (Insulated Gate Bipolar Transistor) or the like may be used instead of the MOSFET transistor.

[0022] Furthermore, in this embodiment, the transistor is preferably a power transistor, preferably a transistor capable of handling a large current of at least 500 A.

[0023] Next, a rectifier element module 10 including first and second transistors Q1 and Q2 (an example of a rectifier element) will be described. Figure 4 , (a) is a top perspective view of the rectifier element module, and (b) is a back perspective view of (a).

[0024] like Figure 4 As shown, the rectifier element module 10 includes an element body 11, a first lead terminal 12, and a second module terminal 13. The element body 11 internally houses a transistor (a first transistor Q1 or a second transistor Q2), which is sealed with resin. The element body 11 includes an element body back surface 11a, an element body front surface 11b, and an element body side surface 11c. In this embodiment, the element body 11 is generally rectangular in shape. The element body back surface 11a is the back surface of the element body 11, the element body front surface 11b is the front surface of the element body 11 opposite the element body back surface 11a, and the element body side surface 11c is the side surface excluding the element body back surface 11a and the element body front surface 11b.

[0025] Hereinafter, the rectifier element module 10 will be described assuming that the first transistor Q1 is arranged inside the element body 11 .

[0026] In this embodiment, the first lead terminal 12 extends from the element body 11. The first lead terminal 12 is formed of a conductive material, for example, a metal with copper as the main component. The first lead terminal 12 has a gate pin 12a, an unused pin 12b and a first module terminal 12c. The gate pin 12a, the unused pin 12b and the first module terminal 12c are arranged in sequence along the back surface 11a of the element body. The unused pin 12b is cut off and not used. The first module terminal 12c is electrically connected to the first source terminal S1. The gate pin 12a is electrically connected to the first gate terminal G1. The gate pin 12a and the first module terminal 12c extend from one of the side surfaces 11c of the element body facing the outside of the element body 11 and extend toward the back surface 11a of the element body. In this embodiment, the gate lead 12a and the first module terminal 12c have a portion extending from the side surface 11c of the element body along the back surface 11a of the element body and a portion bent or curved from the front end of the portion and extending toward the back surface 11a of the element body, but are not limited to this. In addition, one of the surfaces of the side surface 11c of the element body from which the gate lead 12a and the first module terminal 12c are drawn is a surface opposite to the side from which a portion of the second module terminal 13 protrudes from the element body 11. That is, the direction in which the first lead terminal 12 extends from the element body 11 and the direction in which the second module terminal 13 protrudes from the element body 11 are opposite. In addition, in Figure 1 For convenience of explanation, only the first module terminal 12 c of the first lead terminal 12 is shown.

[0027] The second module terminal 13 is electrically connected to the first drain terminal D1. At least a portion of the second module terminal 13 is arranged in contact with the back surface 11a of the component body. In this embodiment, the second module terminal 13 extends in a floor-like shape along the back surface 11a of the component body, with a portion arranged in surface contact with the back surface 11a. The second module terminal 13 is arranged coplanar with the back surface 11a of the component body. Furthermore, the remaining portion of the second module terminal 13 not in contact with the back surface 11a of the component body extends from one of the side surfaces 11c of the component body toward the side opposite to the direction in which the first module terminal 12c extends from the component body 11, extending along the back surface 11a of the component body and toward the exterior of the component body 11. This second module terminal 13 is formed of a conductive material, such as a metal primarily composed of copper.

[0028] In the rectifier element module 10 described above, the first module terminals 12c extend outward from the element body 11 and toward the element body rear surface 11a. At least a portion of the second module terminals 13 is arranged so as to contact the element body rear surface 11a. The rectifier element module 10 described above is, for example, a surface-mount component in the standard state. Thus, since the rectifier element module 10 can be mounted on the substrate 20 in the standard state, no additional installation steps are required.

[0029] like Figure 1 、 Figure 2 As shown, the substrate 20 is a component for arranging the rectifier element module 10. The substrate 20 is plate-shaped and has a substrate surface 21 and a substrate back surface 22. The substrate 20 is arranged along the arrangement surface 51 of the cooling promotion portion 50. Here, the substrate 20 is arranged horizontally, with the substrate surface 21 and substrate back surface 22 being horizontal surfaces. The rectifier element module 10 is arranged on the substrate surface 21 side of the substrate 20. The first module terminal 12c extends from the element body side surface 11c of the element body 11 along the element body back surface 11a, and the tip extending toward the element body back surface 11a is attached to the substrate 20 at the first mounting portion 25. In this embodiment, the first module terminal 12c extends from the element body side surface 11c in the x-direction and downward in the z-direction, and is attached to the substrate 20 at the first mounting portion 25. Furthermore, the first module terminal 12c is electrically connected to the first conductive cooling portion 30 via the first through-hole member 27. The first through-hole component 27 is composed of a conductive component that penetrates the substrate 20 in the thickness direction (z direction) from the substrate surface 21 to the substrate back surface 22. The first through-hole component 27 is provided corresponding to the first mounting portion 25 and electrically connects the first module terminal 12c mounted on the first mounting portion 25 and the first conductive cooling portion 30. Figure 1Although omitted in the figure, the gate pin 12a, like the first module terminal 12c, extends along the element body back surface 11a, and the tip thereof extending toward the element body back surface 11a is attached to the substrate 20. The gate pin 12a is electrically connected to a gate signal circuit (not shown) via, for example, wiring (not shown) on the substrate 20, and receives a supply of the first gate signal g1.

[0030] The component body 11 and the second module terminal 13 are in contact with each other along the substrate surface 21. Specifically, the first module terminal 12c is mounted on the substrate surface 21 in a state extending along the component body back surface 11a and extending toward the component body back surface 11a side. On the other hand, the component body 11 and the second module terminal 13 are mounted on the substrate surface 21 in contact with the substrate surface 21. Hereinafter, the portion where the second module terminal 13 is mounted in contact with the substrate surface 21 is referred to as the second mounting portion 26. In addition, the second module terminal 13 is electrically connected to the second conductive cooling portion 40 via the second penetration component 28. The second penetration component 28 is composed of a conductive component that penetrates the substrate 20 in the thickness direction (z direction) from the substrate surface 21 to the substrate back surface 22. The second penetration component 28 is provided corresponding to the second mounting portion 26 and electrically connects the second module terminal 13 mounted on the second mounting portion 26 and the second conductive cooling portion 40.

[0031] The substrate 20 is provided with at least one through-hole (not shown) that allows the first and second through-hole members 27 and 28 to penetrate from the substrate surface 21 to the substrate back surface 22. The periphery of the through-hole may be coated with a metal such as Cu, Ni, or Sn, for example, by plating. The first and second through-hole members 27 and 28, while inserted into the through-hole, are soldered together with the first and second module terminals 12 c and 13. This electrically connects the first and second module terminals 12 c and 13, as well as the first and second conductive cooling units 30 and 40, via the first and second through-hole members 27 and 28.

[0032] As the substrate 20, a relatively inexpensive resin substrate such as glass epoxy resin, a ceramic substrate, etc. can be used. In addition, the substrate 20 can be a relatively thin substrate having a thickness of, for example, 1.6 mm to 2.0 mm.

[0033] Various electronic components other than the rectifying element module 10 and wirings other than the wirings for the rectifying element module 10 may be arranged on the substrate 20 .

[0034] exist Figure 1In the example, the first conductive cooling portion 30 electrically connects the secondary-side output (-) line Vout(-) (an example of a first external component in this embodiment) disposed externally relative to the cooling unit 100 of the rectifier element module and the first module terminal 12c. The first conductive cooling portion 30 is disposed in contact with the back surface 22 of the substrate. Here, as described above, the first module terminal 12c is electrically connected to the first conductive cooling portion 30 via the first through-component 27. Furthermore, since the first conductive cooling portion 30 is electrically connected to the secondary-side output (-) line Vout(-), the secondary-side output (-) line Vout(-) and the first module terminal 12c are electrically connected via the first conductive cooling portion 30. When the rectifier element module 10 includes a first transistor Q1, the first source terminal S1 and the secondary-side output (-) line Vout(-) are electrically connected via the first conductive cooling portion 30.

[0035] Furthermore, when the rectifier element module 10 includes the first transistor Q1, the first conductive cooling unit 30 primarily cools heat generated by the first current passing through the first source terminal S1. Because a relatively large first current flows through the rectifier element module 10, the heat generated by this current is also relatively large. Considering the situation where the heat generated by the first current is generated within the rectifier element module 10 or in the substrate 20 through which the first current flows, the first conductive cooling unit 30 can cool the heat generated by the substrate 20 and the rectifier element module 10 due to this first current.

[0036] A material having electrical conductivity and a cooling function is used for the first conductive cooling portion 30. The first conductive cooling portion 30 is formed of, for example, a metal such as Cu or Al.

[0037] The first conductive cooling portion 30 can be formed as a wiring or printed pattern, but is preferably configured as a plate-shaped conductive circuit with a stable and rigid appearance. Specifically, it is preferably configured as a busbar. This allows for good electrical conductivity and heat dissipation even when the rectifier element module 10 in the synchronous rectifier circuit 1 handles high currents, such as 500 A or more.

[0038] exist Figure 1In this example, the second conductive cooling portion 40 electrically connects the secondary windings 2c and 2d (an example of a second external component in this embodiment), which are located externally from the cooling unit 100 of the rectifier element module, and the second module terminal 13. The second conductive cooling portion 40 is arranged in contact with the substrate back surface 22 at positions corresponding to the element body 11 and the second module terminal 13. As described above, the second module terminal 13 is electrically connected to the second conductive cooling portion 40 via the second through-component 28. Furthermore, since the second conductive cooling portion 40 is electrically connected to the secondary windings 2c and 2d, the secondary windings 2c and 2d are electrically connected to the second module terminal 13 via the second conductive cooling portion 40. When the rectifier element module includes a first transistor Q1, the first drain terminal D1 is electrically connected to the second partial winding end 2d2 of the second partial winding 2d (an example of a second external component in this embodiment) via the second conductive cooling portion 40.

[0039] Furthermore, when the rectifier element module 10 includes the first transistor Q1, the second conductive cooling portion 40 primarily cools the heat generated by the second current passing through the first drain terminal D1. Because a relatively large second current flows through the rectifier element module 10, the heat generated by this second current is also relatively large. Considering the heat generated by the second current in the rectifier element module 10 or in the substrate 20 through which the second current flows, the second conductive cooling portion 40 can cool the heat generated by the substrate 20 and the rectifier element module 10 due to this second current.

[0040] A material having electrical conductivity and a cooling function is used for the second conductive cooling portion 40. The second conductive cooling portion 40 is formed of, for example, a metal such as Cu or Al.

[0041] The second conductive cooling portion 40 can be formed as a wiring or printed pattern, but is preferably configured as a plate-shaped conductive circuit with a stable and rigid appearance. Specifically, it is preferably configured as a busbar. This allows for good electrical conductivity and heat dissipation even when the rectifier element module 10 in the synchronous rectifier circuit 1 handles high currents, such as 500 A or more.

[0042] The cooling promotion part 50 is directly or indirectly arranged on at least one of the first and second conductive cooling parts 30 and 40 to promote the cooling of at least one of the conductive cooling parts 30 and 40. Figure 1In the example shown, the cooling promotion portion 50 has a horizontal configuration surface 51 serving as the upper surface of the cooling promotion portion 50. The first conductive cooling portion 30 is located between the substrate 20 and the cooling promotion portion 50, in contact with the substrate back surface 22 and the configuration surface 51 of the cooling promotion portion 50. Furthermore, the second conductive cooling portion 40 is located between the substrate 20 and the cooling promotion portion 50, with the insulating member 80 interposed therebetween, in contact with the substrate back surface 22 and disposed on the configuration surface 51 of the cooling promotion portion 50, with the insulating member 80 interposed therebetween. Thus, the first conductive cooling portion 30 is electrically insulated from the second conductive cooling portion 40. This prevents a short circuit between the first module terminal 12c and the second module terminal 13.

[0043] That is, the cooling promotion part 50 has the following structure: it not only promotes the cooling of the first conductive cooling part and the second conductive cooling part 30 and 40, but also works in conjunction with the insulating part 80 by having conductivity, is electrically connected to one of the first conductive cooling part 30 and the second conductive cooling part 40, and is insulatedly connected to the other.

[0044] And, in Figure 1 In the example of FIG, the cooling promotion portion 50 contacts the first conductive cooling portion 30 and directly promotes cooling of the first conductive cooling portion 30 . On the other hand, the cooling promotion portion 50 indirectly promotes cooling of the second conductive cooling portion 40 via the insulating member 80 .

[0045] The cooling promotion unit 50 is not limited in its configuration as long as it can promote the cooling of the first and second conductive cooling units 30 and 40. Examples of the cooling promotion unit 50 include a water-cooled radiator composed of one or more fins and a conduit through which a liquid such as water can flow, or an air-cooled radiator composed of one or more fins capable of dissipating heat.

[0046] More specifically, the cooling promotion unit 50 is preferably formed of a material having electrical and thermal conductivity, such as a metal such as Cu or Al, similar to the first and second conductive cooling units 30 and 40. This allows for excellent electrical conductivity and heat dissipation, along with the first and second conductive cooling units 30 and 40, even when the rectifier element module 10 in the synchronous rectifier circuit 1 handles high currents, such as 500 A or more.

[0047] In the above description, the case where the first transistor Q1 is arranged inside the rectifying element module 10 is described in relation to the case where the second transistor Q2 is arranged inside the rectifying element module 10 . The following description will briefly focus on the differences.

[0048] The first module terminal 12c is electrically connected to the second source terminal S2, the gate pin 12a is electrically connected to the second gate terminal G2, and the second module terminal 13 is electrically connected to the second drain terminal D2.

[0049] The first module terminal 12c extends outward from the element body 11 and toward the element body rear surface 11a, and is mounted on the substrate 20. The first module terminal 12c is electrically connected to the first conductive cooling portion 30 via a first through-piece 27 that penetrates the substrate 20. The gate pin 12a extends outward from the element body 11 and toward the element body rear surface 11a, and is mounted on the substrate 20. The gate pin 12a is electrically connected to a gate signal circuit (not shown) via, for example, wiring (not shown) on the substrate 20, and receives a supply of the second gate signal g2.

[0050] Furthermore, the first conductive cooling portion 30 electrically connects the second source terminal S2 to the secondary-side output (-) line Vout(-) (an example of a first external component in this embodiment), primarily cooling heat generated by the first current flowing through the second source terminal S2. Furthermore, the second conductive cooling portion 40 electrically connects the second drain terminal D2 to the first partial winding start end 2c1 of the first partial winding 2c (an example of a second external component in this embodiment), primarily cooling heat generated by the second current flowing through the second drain terminal D2.

[0051] (2) Overall configuration and structure of the cooling unit for the rectifier element module Next, the arrangement and configuration of the rectifier element module 10 , the substrate 20 , the first conductive cooling portion 30 , the second conductive cooling portion 40 , and the cooling promotion portion 50 in the rectifier element module cooling unit 100 will be summarized and further described.

[0052] like Figure 1 、 Figure 2 As shown, in the cooling unit 100 for a rectifier element module according to this embodiment, the cooling promotion portion 50 is located at the bottom, and the first and second conductive cooling portions 30 and 40 are arranged side by side in the horizontal direction (here, the x-direction) relative to the arrangement surface 51 of the cooling promotion portion 50. The substrate 20 is arranged horizontally on the first and second conductive cooling portions 30 and 40. The rectifier element module 10 is arranged on the substrate 20.

[0053] The first conductive cooling portion 30 is disposed between the substrate 20 and the cooling promotion portion 50. Figure 1 、 Figure 2In the example shown, the first conductive cooling portion 30 is configured as a rectangular parallelepiped, but the present invention is not limited thereto. Furthermore, the first conductive cooling portion 30 has a first contact surface 30a, which serves as a horizontal upper surface, and a second contact surface 30b, which serves as a horizontal lower surface. The first contact surface 30a of the first conductive cooling portion 30 is in surface contact with the substrate back surface 22, while the second contact surface 30b is in surface contact with the placement surface 51 of the cooling promotion portion 50, thereby placing the first conductive cooling portion 30 on the substrate 20. Thus, the substrate 20, the first conductive cooling portion 30, and the cooling promotion portion 50 are in surface contact with each other.

[0054] The first module terminal 12c is attached to the substrate 20 at a first mounting portion 25, extending toward the rear surface 11a of the element body. The first mounting portion 25 faces at least a portion of the first conductive cooling unit 30 across the substrate 20. Specifically, the first conductive cooling unit 30 is located at the portion corresponding to the leading end of the first module terminal 12c, i.e., directly below the first module terminal 12c. Furthermore, the first module terminal 12c is electrically connected to the first conductive cooling unit 30 via, for example, a first penetration member 27 that penetrates the substrate 20 in the thickness direction (z direction).

[0055] The second conductive cooling portion 40 is disposed between the substrate 20 and the cooling promotion portion 50 via the insulating member 80. Figure 1 、 Figure 2 In the example, the second conductive cooling portion 40 is configured as a rectangular parallelepiped, but is not limited thereto. Furthermore, the second conductive cooling portion 40 has a third contact surface 40a serving as a horizontal surface of the upper surface and a fourth contact surface 40b serving as a horizontal surface of the lower surface. The insulating component 80 is arranged between the second conductive cooling portion 40 and the cooling promotion portion 50. The third contact surface 40a of the second conductive cooling portion 40 is in surface contact with the substrate back surface 22 of the substrate 20. In addition, the fourth contact surface 40b of the second conductive cooling portion 40 is in surface contact with the upper surface of the insulating component 80. In addition, the arrangement surface 51 of the cooling promotion portion 50 is in surface contact with the lower surface of the insulating component 80.

[0056] The substrate 20 is arranged in the horizontal direction in a state of being in contact with the first contact surface 30 a of the first conductive cooling portion 30 and the third contact surface 40 a of the second conductive cooling portion 40 .

[0057] The second module terminal 13 is a plate-shaped structure extending along the back surface 11a of the component body. One surface (here, the top surface) of the second module terminal 13 contacts the back surface 11a of the component body. Furthermore, the other surface (here, the bottom surface) of the second module terminal 13 contacts the substrate surface 21 of the substrate 20 and is mounted on the substrate 20 at the second mounting portion 26. In this configuration, the first module terminal 12c extends outward from the component body 11 and toward the back surface 11a of the component body. In the standard state, in which one surface of the second module terminal 13 contacts the back surface 11a of the component body, the other surface of the second module terminal 13 contacts the substrate surface 21. Consequently, the back surface 11a of the component body, the second module terminal 13, the substrate 20, the second conductive cooling portion 40, the insulating component 80, and the cooling promotion portion 50 are in surface contact with each other.

[0058] Furthermore, the second module terminal 13 is electrically connected to the second conductive cooling portion 40 via a second through-hole member 28 or the like that penetrates the substrate 20 in the thickness direction (z-direction). At this point, the second mounting portion 26 faces at least a portion of the second conductive cooling portion 40 across the substrate 20. In other words, the second conductive cooling portion 40 is located directly below the second module terminal 13.

[0059] In this embodiment, if Figure 2 As shown, a plurality of rectifier element modules 10 are arranged in a row along the y direction on the substrate surface 21. Each rectifier element module 10 has a first transistor Q1 or a second transistor Q2 as appropriate. The configuration and arrangement of each rectifier element module 10 are the same as those described above.

[0060] (3) Current path Next, the flow of current in the rectifier element module cooling unit 100 will be described. The flow of current in the rectifier element module cooling unit 100 is the same regardless of whether the first transistor Q1 or the second transistor Q2 is arranged inside the rectifier element module 10.

[0061] Figure 5 Yes Figure 1 A current path diagram showing the flow of current in the cooling unit of the rectifier element module. A portion of the first circuit path 60 for the first current, which runs from the first source terminal S1 (or the second source terminal S2) via the first module terminal 12 c and the first conductive cooling unit 30 to the secondary-side output (-) line Vout(-) (an example of a first external component in this embodiment), is formed by a first through-current path 61 for the first current, which passes through the substrate 20 from the substrate front surface 21 to the substrate back surface 22. The length of the first through-current path 61 is equal to the thickness t of the substrate 20 from the substrate front surface 21 to the substrate back surface 22. Furthermore, a portion of the first circuit path 60 also includes the first conductive cooling path 62 for the first current, which passes through the first conductive cooling unit 30.

[0062] A portion of a second current path 70 for the second current, which runs from the first drain terminal D1 (or the second drain terminal D2) via the second module terminal 13 and the second conductive cooling portion 40 to the second partial winding 2d (or the first partial winding 2c) (an example of a second external member in this embodiment), is formed by a second through-current path 71 that allows the second current to penetrate the substrate 20 from the substrate front surface 21 to the substrate back surface 22. The length of the second through-current path 71 is equal to the thickness t of the substrate 20. Furthermore, a portion of the second current path 70 also includes a second conductive cooling path 72 that allows the second current to pass through the second conductive cooling portion 40.

[0063] When the first transistor Q1 is on and the second transistor Q2 is off, the signal from the secondary-side output (-) line Vout(-) is transmitted as a first current via a first circuit path 60 comprising a first through-current path 61 and a first conductive cooling path 62 to the first source terminal S1. The current then flows from the first source terminal S1 to the first drain terminal D1. Next, a second current flows from the first drain terminal D1 via a second current path 70 comprising a second through-current path 71 and a second conductive cooling path 72 to the second partial winding end 2d2 of the second partial winding 2d. The output voltage induced in the second partial winding 2d is output from the second partial winding start 2d1 and the secondary-side output (+) line Vout(+).

[0064] On the other hand, when the second transistor Q2 is on and the first transistor Q1 is off, the signal from the secondary-side output (-) line Vout(-) is transmitted as a first current via a first circuit path 60 comprising a first through-current path 61 and a first conductive cooling path 62 to the second source terminal S2. The current then flows from the second source terminal S2 to the second drain terminal D2. Next, a second current flows from the second drain terminal D2 via a second current path 70 comprising a second through-current path 71 and a second conductive cooling path 72 to the first partial winding start end 2c1 of the first partial winding 2c. The output voltage induced in the first partial winding 2c is output from the first partial winding end end 2c2 and the secondary-side output (+) line Vout(+).

[0065] (4) Effect (4-1) Effects of the above current paths and configurations In the rectifier element module 10 described above, the first module terminals 12c extend outward from the element body 11 and toward the element body rear surface 11a. At least a portion of the second module terminals 13 is arranged so as to contact the element body rear surface 11a. This allows the rectifier element module 10 to be mounted on the substrate 20 in a standard configuration, eliminating the need for additional installation work.

[0066] Furthermore, according to the above configuration, a portion of the first circuit path 60, which runs from the first and second source terminals S1 and S2 (first element terminals) through the first module terminal 12 c and the first conductive cooling unit 30 to the secondary-side output (-) line Vout(-) (an example of a first external component in this embodiment), is formed by the first through-current path 61. Therefore, compared to a case where the entire first circuit path 60 is formed as wiring on the substrate 20, heating of the substrate 20 caused by the first current flowing through the substrate 20 can be suppressed. Specifically, by reducing the length of the wiring through which the first current flows in the substrate 20, heating of the substrate 20 caused by the first current flowing through this wiring can be suppressed.

[0067] Furthermore, the first conductive cooling path 62 formed by the first conductive cooling portion 30 bears a portion of the first circuit path 60 , thereby reducing the wiring length of the first current flowing through the substrate 20 , thereby suppressing heat generation of the substrate 20 .

[0068] Furthermore, because a portion of the second current path 70, which runs from the first and second drain terminals D1 and D2 (second element terminals) through the second module terminal 13 and the second conductive cooling portion 40 to the secondary windings 2d and 2c (an example of a second external member in this embodiment), is formed by the second through-current path 71, heating of the substrate 20 caused by the second current flowing through the substrate 20 can be suppressed compared to a case where the entire second current path 70 is formed as wiring on the substrate 20. In other words, by reducing the length of the wiring through which the second current flows in the substrate 20, heating of the substrate 20 caused by the second current flowing through this wiring can be suppressed.

[0069] Furthermore, the rectifier element module 10 of the above-described configuration is mounted on the substrate surface 21 along with the first and second module terminals 12c and 13. If the wiring for the first and second currents flowing from the first and second module terminals 12c and 13 is formed on the substrate surface 21 and substrate back surface 22 of the substrate 20, the first and second currents flowing through each wiring on the substrate 20 will generate significant heat. To mitigate this heating of the substrate 20, considerations include using a highly thermally conductive substrate such as a copper or ceramic substrate, increasing the substrate thickness, or increasing the substrate area, such as a so-called copper inlay. However, these approaches increase the cost of the substrate itself, making it impossible to miniaturize or thin the substrate, and necessitating a complex configuration for cooling the substrate. On the other hand, the above-described configuration allows the first and second currents to flow through the first and second through-current paths 61 and 71, thereby suppressing heating of the substrate 20. Consequently, the substrate 20 can be miniaturized and thinned. In addition, it is not necessary to use a substrate with high thermal conductivity, nor is it necessary to use a complicated structure such as a copper inlay.

[0070] Furthermore, heat generated by the first and second transistors Q1 and Q2 (rectifier elements) due to a first current flowing from the first and second source terminals S1 and S2 (first element terminals) is cooled by the first conductive cooling portion 30. Meanwhile, heat generated by the first and second transistors Q1 and Q2 (rectifier elements) due to a second current flowing from the first and second drain terminals D1 and D2 (second element terminals) is cooled by the second conductive cooling portion 40. Thus, heat generated by the first and second transistors Q1 and Q2 (rectifier elements) and the substrate 20 due to the first and second currents can be cooled while preventing a short circuit between the first and second source terminals S1 and S2 (first element terminals) and the first and second drain terminals D1 and D2 (second element terminals).

[0071] In this manner, when the rectifier element module 10, such as a surface-mount component, is mounted on the substrate 20 in a standard state, heating of the substrate 20 caused by the flow of the first and second currents can be suppressed. Furthermore, if heating of the substrate 20 has already occurred, the heat can be cooled by the first and second conductive cooling portions 30 and 40. This prevents the first and second transistors Q1 and Q2 (rectifier elements) from heating due to the heat of the substrate 20. Furthermore, heat generated by the first and second transistors Q1 and Q2 (rectifier elements) themselves can also be cooled by the first and second conductive cooling portions 30 and 40. Consequently, damage to the first and second transistors Q1 and Q2 (rectifier elements) caused by, for example, high junction temperatures can be suppressed. Furthermore, as described above, the reason why the substrate 20 and the first and second transistors Q1 and Q2 (rectifier elements) can be cooled while maintaining the standard state of the rectifier element module 10 is that the following method is adopted: the first source terminal and the second source terminal S1 and S2 (first element terminal) of the first and second transistors Q1 and Q2 (rectifier elements) are connected to the first module terminal 12c extending to the outside of the element body 11, and in addition to this, the first drain terminal and the second drain terminal D1 and D2 (second element terminal) of the first and second transistors Q1 and Q2 (rectifier elements) are connected to the second module terminal 13 in contact with the back side 11a of the element body. In this embodiment of the rectifier element module 10, by arranging the rectifier element module 10, the substrate 20, the first conductive cooling portion 30, the second conductive cooling portion 40, and the cooling promotion portion 50 as described above, the heat generated by the substrate 20 and the first and second transistors Q1 and Q2 (rectifier elements) due to the first and second currents can be more efficiently cooled by the first conductive cooling portion 30, the second conductive cooling portion 40, and the cooling promotion portion 50. Thus, according to this embodiment, a cooling unit 100 for a rectifier element module for cooling the substrate 20 and the first and second transistors Q1 and Q2 (rectifier elements) can be provided.

[0072] Furthermore, the substrate 20 and the first conductive cooling portion 30 are in surface contact via the substrate back surface 22 and the first contact surface 30a. This allows the first conductive cooling portion 30 to cool the substrate 20 more efficiently than in point contact. Furthermore, the first conductive cooling portion 30 and the cooling promotion portion 50 are in surface contact via the second contact surface 30b and the arrangement surface 51. This allows the cooling promotion portion 50 to more efficiently promote cooling of the first conductive cooling portion 30 than in point contact.

[0073] Furthermore, the element body 11 and the second module terminal 13 are in surface contact with each other via the element body back surface 11a and one surface of the second module terminal 13, and the second module terminal 13 and the substrate 20 are in surface contact via the other surface of the second module terminal 13 and the substrate surface 21. Furthermore, the substrate 20 and the second conductive cooling portion 40 are in surface contact via the substrate back surface 22 and the third contact surface 40a. Thus, compared to point contact, the element body 11 and the substrate 20 can be cooled more efficiently by the second conductive cooling portion 40. Furthermore, the second conductive cooling portion 40, the insulating component 80, and the cooling promotion portion 50 are in surface contact with each other. Thus, compared to point contact, the cooling promotion portion 50 can promote cooling of the second conductive cooling portion 40 more efficiently.

[0074] Furthermore, by suppressing the heat generation of the substrate 20 and the heat generation of the first and second transistors Q1 and Q2 (rectifier elements), the temperature of the first and second conductive cooling parts 30 and 40 is also reduced. As a result, the DC resistance Rdc of the first and second conductive cooling parts 30 and 40 can be reduced. As a result, the conduction loss (Idc), which is the product of the square of the current passing through the first and second conductive cooling parts 30 and 40 and the DC resistance Rdc, can be suppressed. 2 Rdc, power loss), therefore, the power conversion efficiency in the power conversion device 1 can be improved.

[0075] Furthermore, if the first and second transistors Q1 and Q2 (rectifier elements) are surface-mount components, they can be joined to the substrate 20 through a reflow process using solder paste applied to the surface-mount components (reflow soldering). This eliminates the need for bolts when joining the first and second transistors Q1 and Q2 (rectifier elements) to the substrate 20. This significantly simplifies the assembly process for attaching the first and second transistors Q1 and Q2 (rectifier elements) to the substrate 20, reducing costs.

[0076] In addition, usually when the transistor (rectifier) ​​is a separate component, the connection between the separate component and the substrate requires a flow soldering process using molten solder. Therefore, when other components on the substrate are surface-mounted components, a combination of a flow soldering process and a reflow process is required in the assembly process. On the other hand, when the first transistor, the second transistor Q1, and Q2 (rectifier) ​​are surface-mounted components, the connection between the first transistor, the second transistor Q1, and Q2 (rectifier) ​​and the substrate 20 can be performed through a reflow process. Therefore, when other components besides the first transistor, the second transistor Q1, and Q2 (rectifier) ​​are also surface-mounted components, the installation process can be performed only through a reflow process.

[0077] (4-2) Effects of Horizontal Configuration of Substrates With the above configuration, the cooling unit 100 for the rectifier element module can be constructed with the substrate 20 arranged parallel to the cooling promoting portion 50 and the first and second conductive cooling portions 30 and 40. This allows the substrate 20 to be stably positioned relative to the cooling promoting portion 50 and the first and second conductive cooling portions 30 and 40. Specifically, when the first and second module terminals 12 c and 13 are mounted on the substrate 20 in a standard surface-mount configuration, the substrate 20, the first and second conductive cooling portions 30 and 40, and the cooling promoting portion 50 can be stably positioned so that they are in surface contact with each other.

[0078] (4-3) Effects of the mounting portion facing the conductive cooling portion (a) Effects of the first mounting portion and the first conductive cooling portion facing each other According to the above configuration, since the first mounting portion 25 faces the first conductive cooling unit 30 across the substrate 20, the first module terminal 12c can be connected to the first conductive cooling unit 30 via the first through-current path 61 at the first mounting portion 25, without using wiring on the substrate 20. This effectively suppresses heating of the substrate 20 caused by the first current flowing through the substrate 20. Consequently, damage to the first and second transistors Q1 and Q2 (rectifier elements) caused by heating of the substrate 20 can be effectively suppressed.

[0079] (b) Effects of the second mounting portion and the second conductive cooling portion facing each other With this configuration, since the second mounting portion 26 faces the second conductive cooling unit 40 across the substrate 20, the second module terminal 13 can be connected to the second conductive cooling unit 40 via the second through-current path 71 at the second mounting portion 26, without requiring wiring on the substrate 20. This effectively suppresses heating of the substrate 20 caused by the second current flowing through it. Consequently, damage to the first and second transistors Q1 and Q2 (rectifier elements) caused by heating of the substrate 20 can be effectively suppressed.

[0080] (4-4) Effects of the Rectifier Element Module Constituting the Converter's Secondary Circuit In the above-described embodiment, the first external component is the output line (secondary-side output (-) line Vout(-)) on the secondary side of inverter 2, and the second external component is the secondary-side windings 2c and 2d of inverter 2. Furthermore, the rectifier element module 10 constitutes the secondary-side circuit 4 of inverter 2, and is susceptible to generating significant heat due to the large current flowing through it. As described above, since a portion of the first circuit path 60 for the first current flowing through the first and second source terminals S1 and S2 (first element terminals) is formed by the first through-current path 61, heating of the substrate 20 itself and heating of the first and second transistors Q1 and Q2 (rectifier elements) can be suppressed. Furthermore, since a portion of the first circuit path 60 is formed by the first conductive cooling portion 30, i.e., the first conductive cooling path 62, heating of the substrate 20 itself and heating of the first and second transistors Q1 and Q2 (rectifier elements) can also be suppressed. Similarly, since a portion of the second current path 70 for the second current flowing through the first and second drain terminals D1 and D2 (second element terminals) is formed by the second through-current path 71, heating of the substrate 20 itself and heating of the first and second transistors Q1 and Q2 (rectifier elements) can be suppressed. Furthermore, since a portion of the second current path 70 is formed by the second conductive cooling portion 40, namely the second conductive cooling path 72, heating of the substrate 20 itself and heating of the first and second transistors Q1 and Q2 (rectifier elements) can also be suppressed. Therefore, the cooling unit 100 for the rectifier element module described above is useful when used in the secondary side circuit 4 of the inverter 2.

[0081] As another example, the following example can be cited: the first external component is a secondary-side winding of converter 2, and the second external component is an output line on the secondary side of converter 2. Furthermore, as another example, the first external component and the second external component are output lines on the secondary side of converter 2, and the polarities of the output lines are different.

[0082] (4-5) The cooling promotion portion 50 has an effect due to its configuration of being electrically connected to one of the first conductive cooling portion 30 and the second conductive cooling portion 40 and being insulated from the other.

[0083] In the above embodiment, the cooling-promoting portion 50 is electrically connected to one of the first and second conductive cooling portions 30 and 40 via the arrangement surface 51, and is insulated from the other. Thus, the first and second conductive cooling portions 30, 40, and cooling-promoting portion 50 are integrally formed, improving the cooling efficiency of the cooling unit. Furthermore, the substrate 20 is also integrated with the first and second conductive cooling portions 30, 40, further enhancing the cooling efficiency of the cooling unit.

[0084] 2. Modification of Implementation 1 2-1. Modification of the Rectifier Element Module Cooling Unit In the above-mentioned embodiment 1, Figure 1 and Figure 2 The cooling unit 100 for the rectifier element module is described as an example. However, the cooling unit for the rectifier element module is not limited thereto, and for example, the cooling unit for the rectifier element module described below may also be used.

[0085] (1) Other methods of cooling the entire rectifier element module (1-1) Other methods 1 A cooling unit 100A for a rectifier element module according to another aspect 1 of the first embodiment of the present invention will be described. Figure 6A 1 is a side view of a cooling unit for a rectifier element module according to another embodiment 1 of the present invention. Figure 1 Compared to the rectifier module cooling unit 100 shown in FIG. 1 , the insulating member 80 is positioned differently. Only the differences are described below. In the rectifier module cooling unit 100, the insulating member 80 is positioned between the second conductive cooling unit 40 and the cooling promotion unit 50. However, in the rectifier module cooling unit 100A, the insulating member 80 is positioned between the first conductive cooling unit 30 and the cooling promotion unit 50. Since only the position of the insulating member 80 differs, the first conductive cooling unit 30 and the second conductive cooling unit 40 are electrically insulated from each other.

[0086] (1-2) Other methods 2 A cooling unit 100B for a rectifier element module according to another aspect 2 of the first embodiment of the present invention will be described. Figure 6B 1 is a side view of a cooling unit for a rectifier element module according to another embodiment of the present invention. Figure 1 Compared to the cooling unit 100 for the rectifier element module shown in FIG, the arrangement position of the cooling promotion portion 50 differs. Only the differences are described below. In the cooling unit 100 for the rectifier element module, the first conductive cooling portion 30 and the second conductive cooling portion 40 are arranged on the arrangement surface 51 of the cooling promotion portion 50. However, in the cooling unit 100B for the rectifier element module, only the second conductive cooling portion 40 is arranged directly on the arrangement surface 51 of the cooling promotion portion 50, without intervening through the insulating member 80. The first conductive cooling portion 30 is not arranged on the arrangement surface 51. The first conductive cooling portion 30 and the second conductive cooling portion 40 are electrically insulated from each other.

[0087] (2) Modifications of Components of the Rectifier Element Module Cooling Unit (2-1) In the first embodiment described above, the first and second conductive cooling portions 30 and 40 are rectangular parallelepiped-shaped. However, the first conductive cooling portion 30 only needs to electrically connect the first module terminal 12c and the secondary-side output (-) line Vout(-) and cool the heat generated by the first current. Furthermore, the second conductive cooling portion 40 only needs to electrically connect the second module terminal 13 and the secondary-side windings 2c and 2d and cool the heat generated by the second current. The shapes of the first and second conductive cooling portions 30 and 40 are not limited. For example, the first and second conductive cooling portions 30 and 40 can be L-shaped when viewed from the side.

[0088] (2-2) In the first embodiment described above, the first conductive cooling portion 30 is located directly below the first module terminal 12c. However, the first module terminal 12c and the first conductive cooling portion 30 may be slightly separated, within a range that can suppress adverse effects such as damage to the rectifier element caused by the heat generated by the first current. For example, the first mounting portion 25 and the first conductive cooling portion 30 may be slightly separated in the x-direction. In this case, it is sufficient to form wiring on the substrate surface 21 or the substrate back surface 22 to electrically connect the separated portion between the first mounting portion 25 and the first conductive cooling portion 30. In order to suppress the heating of the substrate 20 caused by the passage of the first current, the wiring is preferably short.

[0089] Similarly, the second conductive cooling portion 40 is located directly below the second module terminal 13. However, the second module terminal 13 and the second conductive cooling portion 40 may be slightly separated, to the extent that the heat generated by the second current can be suppressed to prevent damage to the rectifier element. For example, the second mounting portion 26 and the second conductive cooling portion 40 may be slightly separated in the x-direction. In this case, wiring electrically connecting the separation between the second mounting portion 26 and the second conductive cooling portion 40 can be formed on the substrate surface 21 or substrate back surface 22. To suppress heating of the substrate 20 caused by the second current, this wiring is preferably short.

[0090] (2-3) In the first embodiment described above, the first and second penetrating members 27 and 28 are provided separately from the rectifier element module 10. However, the first and second module terminals 12c and 13 may have penetrating portions that penetrate the substrate 20 and are connected to the first and second conductive cooling units 30 and 40 via these penetrating portions. For example, the tip of the first module terminal 12c may have a pin-shaped penetrating portion that penetrates the substrate 20, and this penetrating portion penetrates the substrate 20 and is electrically connected to the first conductive cooling unit 30. Alternatively, the second module terminal 13 may have a pin-shaped penetrating portion that penetrates the substrate on its other surface, and this penetrating portion penetrates the substrate 20 and is electrically connected to the second conductive cooling unit 40. In this case, the first and second penetrating members 27 and 28 may be omitted.

[0091] (2-4) In the first embodiment described above, the rectifier element module 10 has a three-pin structure consisting of the gate pin 12a, the unused pin 12b, and the first module terminal 12c. However, the number of pins of the rectifier element module 10 is not limited. In the first embodiment described above, the unused pin 12b is shorter than the gate pin 12a and the first module terminal 12c. However, the unused pin 12b can also be longer. Since the unused pin 12b is unused, it is not electrically connected to the substrate 20 or other components.

[0092] (2-5) In the first embodiment described above, the second through-current path 71 electrically connects the element body 11 of the rectifier element module 10 and the cooling promotion unit 50 via the second module terminal 13 and is in contact with the element body 11 of the rectifier element module 10. However, the second through-current path 71 may be formed so as to be drawn out and coiled around a portion not in contact with the element body 11. In this manner, heat from the substrate 20 escapes to the second conductive cooling unit 40 via the second through-current path 71, further improving the heat dissipation performance of the cooling unit 100 of the rectifier element module. What is important is that the second through-current path only needs to be configured to penetrate the substrate from the substrate surface to the substrate back surface, and other aspects are not limited by the specific embodiment.

[0093] 3. Implementation Method 2 (1) Configuration of the cooling unit for the rectifier element module The following describes the configuration of a cooling unit 200 for a rectifier element module according to a second embodiment of the present invention, with reference to the accompanying drawings. Components identical or corresponding to those in the first embodiment are denoted by the same reference numerals, and detailed descriptions of these components and related contents, except for those specifically noted below, will be omitted for the portions identical to those in the first embodiment. Figure 7It is a side view of a cooling unit of a rectifier element module according to an embodiment of the present invention. Figure 8 It is a plan view of a cooling unit of a rectifier element module according to an embodiment of the present invention.

[0094] The cooling unit 200 for the rectifier element module according to the second embodiment has a different configuration from that of the first embodiment in that the substrate 20 extends mainly in the z-direction and that a rectifier element module 210 as a separate component is provided in place of the rectifier element module 10 as a surface-mounted component.

[0095] In this embodiment, the rectifier elements of the rectifier element module 210 also constitute a synchronous rectifier circuit for Figure 3 Inside the power conversion device 1 shown.

[0096] In this embodiment, the transistor is also, for example, a MOSFET transistor (Metal Oxide Semiconductor Field Effect Transistor). However, an IGBT (Insulated Gate Bipolar Transistor) or the like may be used instead of the MOSFET transistor.

[0097] Furthermore, in this embodiment, the transistor is preferably a power transistor, and preferably a transistor capable of handling a large current of at least 500 A.

[0098] A rectifier element module 210 including a first transistor and a second transistor Q1 and Q2 (an example of a rectifier element) will be described. Figure 9 , (a) is a top perspective view of the rectifier element module, and (b) is a back perspective view of (a).

[0099] like Figure 9 As shown, the rectifier element module 210 includes an element body 211, a first lead terminal 212, and a second module terminal 213. The element body 211 has a transistor (a first transistor Q1 or a second transistor Q2) configured therein, and the transistor is formed by being sealed with resin. The element body 211 has an element body back surface 211a, an element body front surface 211b, and an element body side surface 211c. In this embodiment, the element body 211 has a roughly rectangular parallelepiped shape, with the element body back surface 211a being the back surface of the element body 211, the element body front surface 211b being the front surface of the element body 211 opposite the element body back surface 211a, and the element body side surface 211c being the side surface excluding the element body back surface 211a and the element body front surface 211b.

[0100] Hereinafter, the rectifier element module 10 will be described assuming that the first transistor Q1 is arranged inside the element body 211 .

[0101] In this embodiment, the first lead terminal 212 extends from the component body 211. The first lead terminal 212 is formed of a conductive material, for example, a metal mainly composed of copper. The first lead terminal 212 includes a gate pin 212a, an unused pin 212b, and a first module terminal 212c. The gate pin 212a, the unused pin 212b, and the first module terminal 212c are arranged in sequence along the back surface 211a of the component body. The unused pin 212b is cut off and is not used. The first module terminal 212c is electrically connected to the first source terminal S1. The gate pin 212a is electrically connected to the first gate terminal G1. The gate pin 212a and the first module terminal 212c extend from one of the side surfaces 211c of the component body to the outside of the component body 211 along the back surface 211a of the component body to the outside of the component body 211. In addition, one of the side surfaces 211c of the element body from which the gate lead 212a and the first module terminal 212c are led is opposite to the side from which a portion of the second module terminal 213 protrudes from the element body 211. In other words, the direction in which the first lead terminal 212 extends from the element body 211 and the direction in which the second module terminal 213 protrudes from the element body 211 are opposite to each other. Figure 7 For the convenience of explanation, only the first module terminal 212c of the first lead terminal 212 is shown.

[0102] The second module terminal 213 is electrically connected to the first drain terminal D1. At least a portion of the second module terminal 213 is arranged in contact with the element body back surface 211a. In this embodiment, the second module terminal 213 extends in a floor-like shape along the element body back surface 211a, with a portion arranged in surface contact with the element body back surface 211a. The second module terminal 213 is arranged coplanar with the element body back surface 211a. Furthermore, the remaining portion of the second module terminal 213 not in contact with the element body back surface 211a extends from one of the element body side surfaces 211c toward the side opposite to the direction in which the first module terminal 212c extends from the element body 211, extending along the element body back surface 211a and toward the exterior of the element body 211. The portion of the second module terminal 213 extending toward the exterior of the element body 211 is provided with a fixing hole 213a for inserting a fastener (not shown) used to attach the rectifier element module 210 to the substrate 20. This second module terminal 213 is formed of a conductive material, such as a metal primarily composed of copper.

[0103] In the aforementioned rectifier element module 210, the first module terminal 212c extends outward from the element body 211 along the element body rear surface 11a, and at least a portion of the second module terminal 213 is arranged along the element body rear surface 211a. The aforementioned rectifier element module 210 is, for example, a separate component in a standard state in which the first module terminal 212c is unbent and extends outward from the element body 211. The standard state in which the first module terminal 212c is unbent refers to, for example, a state in which the first module terminal 212c maintains its standard state as a separate component, extending outward from the element body 211 while remaining along the element body rear surface 211a. Furthermore, the unbent state in which the first module terminal 212c is unbent also includes a state in which the first module terminal 212c is not bent toward the element body rear surface 211a from its standard state as a separate component, but is slightly bent in a direction that is not along the element body rear surface 211a. In this embodiment, the first module terminal 212c is configured as a standard state to extend outside the element body 211 along the element body back surface 211a. In this embodiment, the gate pin 212a also extends outside the element body 211 along the element body back surface 11a, similarly to the first module terminal 212c.

[0104] like Figure 7 、 Figure 8 As shown, the substrate 20 is a component for configuring the rectifier element module 210. The substrate 20 is formed in a plate shape and has a substrate surface 21 and a substrate back surface 22. In the present embodiment, the substrate 20 is arranged upright relative to the cooling promotion portion 50. Here, the substrate 20 is arranged upright in the vertical direction. Thus, the substrate surface 21 and the substrate back surface 22 are along the vertical plane. The rectifier element module 210 is arranged on the substrate surface 21 side of the substrate 20. The first module terminal 212c extends in a vertical direction (here, the x direction) relative to the substrate surface 221 and is mounted on the substrate 20 at the first mounting portion 25. Furthermore, the first module terminal 212c is inserted from the substrate surface 21 to the substrate back surface 22 into the pin hole described later and passes through the substrate 20, and is electrically connected to the first conductive cooling portion 30. Although in Figure 7 Although omitted in the figure, the gate pin 212a, like the first module terminal 212c, extends perpendicularly to the substrate surface 21 and is mounted on the substrate 20. The gate pin 212a is electrically connected to a gate signal circuit (not shown) via, for example, wiring (not shown) on the substrate 20, and receives a supply of the first gate signal g1.

[0105] In this embodiment, the component body 211 and the second module terminal 213 are separated upward from the substrate surface 221. Here, the first module terminal 212c is mounted on the substrate surface 221 in a standard position extending along the component body rear surface 211a. As a result, the component body 211 and the second module terminal 213 are positioned away from the substrate 20 relative to the first mounting portion 25 where the first module terminal 212c is mounted on the substrate 20.

[0106] The substrate 20 is provided with at least one pin hole (not shown) extending through the substrate 20 from the substrate surface 21 to the substrate back surface 22. The at least one pin hole is provided corresponding to the first module terminal 212c. The at least one pin hole can be provided corresponding to the unused pin 212b and the gate pin 212a, respectively. The peripheral surface of the pin hole can also be coated with a metal such as Cu, Ni, or Sn, for example, by plating. The first module terminal 212c is soldered while inserted into the pin hole, securing the rectifier element module 210 to the substrate 20. The first module terminal 212c is electrically connected to the first conductive cooling portion 30 located on the substrate back surface 22 by penetrating the substrate 20 through the pin hole.

[0107] exist Figure 7 In the example, the first conductive cooling unit 30 electrically connects the secondary-side output (-) line Vout(-) (an example of a first external component in this embodiment) disposed externally relative to the cooling unit 200 of the rectifier element module and the first module terminal 212c. The first conductive cooling unit 30 is disposed in contact with the substrate back surface 22. As described above, the first module terminal 212c is electrically connected to the first conductive cooling unit 30 while being inserted into and secured in a pin hole penetrating the substrate 20. For example, the front end of the first module terminal 212c protrudes toward the substrate back surface 22 of the substrate 20, and this protruding portion contacts and electrically connects to the first conductive cooling unit 30. Furthermore, since the first conductive cooling unit 30 is electrically connected to the secondary-side output (-) line Vout(-), the secondary-side output (-) line Vout(-) and the first module terminal 212c are electrically connected via the first conductive cooling unit 30. When the rectifying element module 210 includes the first transistor Q1 , the first source terminal S1 and the secondary-side output (−) line Vout(−) are electrically connected via the first conductive cooling portion 30 .

[0108] Furthermore, when the rectifier element module 210 includes the first transistor Q1, the first conductive cooling unit 30 primarily cools the heat generated by the first current passing through the first source terminal S1. Because a relatively large first current flows through the rectifier element module 210, the heat generated by this current is also relatively large. Considering the situation where the heat generated by the first current is generated within the rectifier element module 210 or in the substrate 20 through which the first current passes, the first conductive cooling unit 30 can cool the heat generated by the substrate 20 and the rectifier element module 210 due to this first current.

[0109] As in the first embodiment, Figure 7 In this example, the second conductive cooling portion 40 electrically connects the secondary windings 2c and 2d (an example of a second external component in this embodiment), which are located externally from the cooling unit 200 of the rectifier element module, and the second module terminal 213. Specifically, when the rectifier element module includes a first transistor Q1, the second conductive cooling portion 40 electrically connects the first drain terminal D1 and the second partial winding end 2d2 of the second partial winding 2d (an example of a second external component in this embodiment). Similar to the rectifier element module 210, the second conductive cooling portion 40 is located on the substrate surface 21 side. The second module terminal 213 is mounted in contact with the second conductive cooling portion 40. This contact portion is hereinafter referred to as the second mounting portion 26.

[0110] Furthermore, when the rectifier element module 210 includes the first transistor Q1, the second conductive cooling unit 40 primarily cools the heat generated by the second current passing through the first drain terminal D1. Because the second current flows through the rectifier element module 210 at a relatively high level, the heat generated by this current is also relatively high. Considering the heat generated by the second current in the rectifier element module 210 or in the substrate 20 through which the second current flows, the second conductive cooling unit 40 can cool the heat generated by the substrate 20 and the rectifier element module 210 due to this second current.

[0111] The cooling promotion part 50 is directly or indirectly arranged on at least one of the first and second conductive cooling parts 30 and 40 to promote the cooling of at least one of the conductive cooling parts 30 and 40. Figure 7In the example shown, the cooling promotion portion 50 has a horizontal placement surface 51 serving as the upper surface of the cooling promotion portion 50. The first conductive cooling portion 30 is arranged in contact with the substrate back surface 22 and the placement surface 51 of the cooling promotion portion 50. Furthermore, the second conductive cooling portion 40 is indirectly placed on the placement surface 51 of the cooling promotion portion 50 while being insulated from the cooling promotion portion 50 via the insulating member 80. This electrically insulates the first conductive cooling portion 30 from the second conductive cooling portion 40. This prevents a short circuit between the first module terminal 212c and the second module terminal 213.

[0112] That is, the cooling promotion part 50 has the following structure: it not only promotes the cooling of the first conductive cooling part and the second conductive cooling part 30 and 40, but also works in conjunction with the insulating part 80 by having conductivity, is electrically connected to one of the first conductive cooling part 30 and the second conductive cooling part 40, and is insulatedly connected to the other.

[0113] And, in Figure 7 In the example shown in FIG. 5 , the cooling promoting portion 50 contacts the first conductive cooling portion 30 and directly promotes cooling of the first conductive cooling portion 30. Meanwhile, the cooling promoting portion 50 indirectly promotes cooling of the second conductive cooling portion 40 via the insulating member 80. Furthermore, the substrate 20 is arranged on the arrangement surface 51 while being insulated from the cooling promoting portion 50 via the insulating member 80.

[0114] As in the first embodiment, the cooling promotion unit 50 is not limited in configuration as long as it can promote cooling of the first and second conductive cooling units 30 and 40. Examples of the cooling promotion unit 50 include a water-cooled radiator composed of one or more fins and a conduit through which a liquid such as water can flow, or an air-cooled radiator composed of one or more fins capable of dissipating heat.

[0115] In the above description, the case where the first transistor Q1 is arranged inside the rectifier element module 210 is described in relation to the case where the second transistor Q2 is arranged inside the rectifier element module 210 . The following description will briefly focus on the differences.

[0116] The first module terminal 212c is electrically connected to the second source terminal S2, the gate pin 212a is electrically connected to the second gate terminal G2, and the second module terminal 213 is electrically connected to the second drain terminal D2.

[0117] The first module terminal 212c extends perpendicularly to the substrate surface 21, penetrates the substrate 20, and is electrically connected to the first conductive cooling portion 30. The gate pin 212a extends perpendicularly to the substrate surface 21, is electrically connected to a gate signal circuit (not shown) via, for example, wiring (not shown) on the substrate 20, and receives a second gate signal g2.

[0118] Furthermore, the first conductive cooling portion 30 electrically connects the second source terminal S2 to the secondary-side output (-) line Vout(-) (an example of a first external component in this embodiment), primarily cooling heat generated by the first current flowing through the second source terminal S2. Furthermore, the second conductive cooling portion 40 electrically connects the second drain terminal D2 to the first partial winding start end 2c1 of the first partial winding 2c (an example of a second external component in this embodiment), primarily cooling heat generated by the second current flowing through the second drain terminal D2.

[0119] (2) Overall configuration and structure of the cooling unit for the rectifier element module Next, the arrangement and configuration of the rectifier element module 210 , the substrate 20 , the first conductive cooling portion 30 , the second conductive cooling portion 40 , and the cooling promotion portion 50 in the rectifier element module cooling unit 200 will be summarized and further described.

[0120] like Figure 7 、 Figure 8 As shown, in the cooling unit 200 for a rectifier element module of this embodiment, a cooling promotion portion 50 is disposed at the bottom, and a substrate 20 is vertically disposed (in this embodiment, the z-direction) relative to a surface 51 on which the cooling promotion portion 50 is disposed. On the cooling promotion portion 50, the rectifier element module 210 and the second conductive cooling portion 40 are disposed on the substrate surface 21 side, with the substrate 20 interposed therebetween, and the first conductive cooling portion 30 is disposed on the substrate back surface 22 side.

[0121] The first conductive cooling portion 30 is in contact with the substrate back surface 22 and is also in contact with the arrangement surface 51 of the cooling promotion portion 50 and is placed on the cooling promotion portion 50. Figure 7 、 Figure 8 In the example shown, the first conductive cooling portion 30 is formed into an L-shape when viewed from the side, comprising a first portion 31 extending in a plate-like manner along a vertical plane (a plane perpendicular to the xy plane) and a second portion 32 extending in a plate-like manner along a horizontal direction (a plane parallel to the xy plane). However, the present invention is not limited to this. The first portion 31 has a planar first portion contact surface 31a that is in surface contact with the substrate back surface 22, and the second portion 32 has a planar second portion contact surface 32a that is in surface contact with the arrangement surface 51 of the cooling promotion portion 50.

[0122] The first module terminal 212c is mounted on the substrate 20 at the first mounting portion 25, penetrating the substrate 20 in the thickness direction (x-direction) from the substrate surface 21 to the substrate back surface 22. The first mounting portion 25 faces at least a portion of the first portion 31 across the substrate 20. Specifically, the first portion 31 is located at the portion corresponding to the leading end of the first module terminal 212c, i.e., directly below the first module terminal 212c. Furthermore, the first module terminal 212c is electrically connected to the first portion 31, either directly or via welding, and is thereby electrically connected to the first conductive cooling unit 30, which includes the first and second portions 31 and 32.

[0123] The second conductive cooling portion 40 is placed on the cooling promotion portion 50 via the insulating member 80 on the substrate surface 21 side. Figure 7 、 Figure 8 In the example of FIG. 1 , the second conductive cooling portion 40 is in contact with the substrate surface 21 of the substrate 20 and is configured to be perpendicular to the substrate surface 21. Figure 7 The insulating member 80 is a rectangular parallelepiped extending in the x-direction (in the x-direction), having a horizontal third contact surface 40a (here, the upper surface) and a horizontal fourth contact surface 40b (here, the lower surface). The insulating member 80 is disposed corresponding to the portion of the arrangement surface 51 where the second conductive cooling unit 40 and substrate 20 are mounted. Furthermore, with the fourth contact surface 40b in surface contact with the insulating member 80, the second conductive cooling unit 40 is mounted on the cooling promotion unit 50 via the insulating member 80. Furthermore, the rectifier element module 210 is disposed with the second module terminal 213 in surface contact with the third contact surface 40a of the second conductive cooling unit 40.

[0124] As described above, the first conductive cooling portion 30 is arranged in contact with the substrate rear surface 22, while the second conductive cooling portion 40 is arranged in contact with the substrate front surface 21. However, the second conductive cooling portion 40 is not electrically connected to the substrate 20, and the first conductive cooling portion 30 is not electrically connected to the second conductive cooling portion 40. In this way, the first and second conductive cooling portions 30 and 40 contact and support the substrate 20 from both the substrate front surface 21 and the substrate rear surface 22, thereby stably positioning the substrate 20 upright in a vertical direction relative to the arrangement surface 51 of the cooling promotion portion 50.

[0125] The second module terminal 213 is a plate-shaped structure extending along the back surface 211a of the component body. One surface (here, the top surface) is in surface contact with the back surface 211a of the component body. Furthermore, the other surface (here, the bottom surface) of the second module terminal 213 is in surface contact with the third contact surface 40a of the second conductive cooling unit 40, and the second conductive cooling unit 40 is mounted on the second mounting portion 26. In this configuration, while the first module terminal 212c extends perpendicularly to the substrate 20, the other surface of the second module terminal 213 is in surface contact with the third contact surface 40a of the second conductive cooling unit 40. Furthermore, the back surface 211a of the component body, the second module terminal 213, the second conductive cooling unit 40, the insulating component 80, and the cooling promotion unit 50 are in surface contact with each other.

[0126] In this embodiment, if Figure 8 As shown, a plurality of rectifier element modules 210 are arranged in a row along the y direction on the substrate surface 21. Each rectifier element module 210 has a first transistor Q1 or a second transistor Q2 as appropriate. The structure and arrangement of each rectifier element module 210 are the same as those described above.

[0127] (3) Current path Next, the flow of current in the rectifier module cooling unit 200 will be described. The flow of current in the rectifier module cooling unit 200 is the same regardless of whether the first transistor Q1 or the second transistor Q2 is disposed inside the rectifier module 210.

[0128] Figure 10 Yes Figure 7 A current path diagram showing the flow of current in the cooling unit of the rectifier element module. A portion of the first circuit path 60 for the first current, which runs from the first source terminal S1 (or the second source terminal S2) via the first module terminal 12 c and the first conductive cooling unit 30 to the secondary-side output (-) line Vout(-) (an example of a first external component in this embodiment), is formed by a first through-current path 61 for the first current, which passes through the substrate 20 from the substrate front surface 21 to the substrate back surface 22. The length of the first through-current path 61 is equal to the thickness t of the substrate 20 from the substrate front surface 21 to the substrate back surface 22. Furthermore, a portion of the first circuit path 60 also includes the first conductive cooling path 62 for the first current, which passes through the first conductive cooling unit 30.

[0129] A portion of the second current path 70 of the second current, which extends from the first drain terminal D1 (or the second drain terminal D2) via the second module terminal 13 and the second conductive cooling portion 40 to the second partial winding 2d (or the first partial winding 2c) (an example of a second external component in this embodiment), is composed of a second conductive cooling path 72 where the second current passes through the second conductive cooling portion 40 without passing through the substrate 20.

[0130] When the first transistor Q1 is on and the second transistor Q2 is off, the signal from the secondary-side output (-) line Vout(-) is transmitted as a first current via a first circuit path 60 comprising a first through-current path 61 and a first conductive cooling path 62 to the first source terminal S1. The current then flows from the first source terminal S1 to the first drain terminal D1. Next, a second current flows from the first drain terminal D1 via a second current path 70 comprising a second conductive cooling path 72 to the second partial winding end 2d2 of the second partial winding 2d. The output voltage induced in the second partial winding 2d is output from the second partial winding start 2d1 and the secondary-side output (+) line Vout(+).

[0131] On the other hand, when the second transistor Q2 is on and the first transistor Q1 is off, the signal from the secondary-side output (-) line Vout(-) is transmitted as a first current via the first circuit path 60, which includes the first through-current path 61 and the first conductive cooling path 62, to the second source terminal S2. The current then flows from the second source terminal S2 to the second drain terminal D2. Next, a second current flows from the second drain terminal D2 via the second current path 70, which includes the second conductive cooling path 72, to the first partial winding start end 2c1 of the first partial winding 2c. The output voltage induced in the first partial winding 2c is output from the first partial winding end end 2c2 and the secondary-side output (+) line Vout(+).

[0132] (4) Effect (4-1) Effects of the above current paths and configurations According to the above configuration, since the first module terminal 212 c can be mounted on the substrate 20 in the standard state of the rectifier element module 210 in which the first module terminal 212 c is not bent, the man-hours for the bending process can be omitted or reduced.

[0133] Furthermore, according to the above configuration, a portion of the first circuit path 60, which runs from the first and second source terminals S1 and S2 (first element terminals) through the first module terminal 212 c and the first conductive cooling unit 30 to the secondary-side output (-) line Vout(-) (an example of a first external component in this embodiment), is formed by the first through-current path 61. Therefore, compared to a case where the entire first circuit path 60 is formed as wiring on the substrate 20, heating of the substrate 20 caused by the first current flowing through the substrate 20 can be suppressed. Specifically, by reducing the length of the wiring through which the first current flows in the substrate 20, heating of the substrate 20 caused by the first current flowing through this wiring can be suppressed.

[0134] Furthermore, the first conductive cooling path 62 formed by the first conductive cooling portion 30 bears a portion of the first circuit path 60 , thereby reducing the wiring length of the first current flowing through the substrate 20 , thereby suppressing heat generation of the substrate 20 .

[0135] Furthermore, a portion of the second current path 70 for the second current, which flows from the first and second drain terminals D1 and D2 (second element terminals) via the second module terminal 213 and the second conductive cooling unit 40 to the secondary windings 2d and 2c (an example of a second external member in this embodiment), is formed by the second conductive cooling path 72 formed by the second conductive cooling unit 40, rather than through the substrate 20. Therefore, compared to a case where the entire second current path 70 is formed as wiring on the substrate 20, heating of the substrate 20 caused by the flow of the second current can be suppressed.

[0136] Furthermore, heat generated by the first and second transistors Q1 and Q2 (rectifier elements) due to a first current flowing from the first and second source terminals S1 and S2 (first element terminals) is cooled by the first conductive cooling portion 30. Meanwhile, heat generated by the first and second transistors Q1 and Q2 (rectifier elements) due to a second current flowing from the first and second drain terminals D1 and D2 (second element terminals) is cooled by the second conductive cooling portion 40. Thus, heat generated by the first and second transistors Q1 and Q2 (rectifier elements) and the substrate 20 due to the first and second currents can be cooled while preventing a short circuit between the first and second source terminals S1 and S2 (first element terminals) and the first and second drain terminals D1 and D2 (second element terminals).

[0137] In this manner, when the rectifier element module 210, such as a separate component, is mounted on the substrate 20 in a standard state with the first module terminal 12c unbent, heating of the substrate 20 caused by the flow of the first and second currents can be suppressed. Furthermore, if heating of the substrate 20 has already occurred, the heat can be cooled by the first and second conductive cooling portions 30 and 40. This prevents the first and second transistors Q1 and Q2 (rectifier elements) from heating due to the heat generated by the substrate 20. Furthermore, heat generated by the first and second transistors Q1 and Q2 (rectifier elements) themselves can also be cooled by the first and second conductive cooling portions 30 and 40. Consequently, damage to the first and second transistors Q1 and Q2 (rectifier elements) caused by, for example, elevated junction temperatures can be suppressed. Furthermore, as described above, the reason why the substrate 20 and the first and second transistors Q1 and Q2 (rectifier elements) can be cooled while maintaining the standard state of the rectifier element module 10 is that the following method is adopted: the first source terminal and the second source terminal S1 and S2 (first element terminal) of the first and second transistors Q1 and Q2 (rectifier elements) are connected to the first module terminal 212c extending to the outside of the element body 211, and in addition to this, the first drain terminal and the second drain terminal D1 and D2 (second element terminal) of the first and second transistors Q1 and Q2 (rectifier elements) are connected to the second module terminal 213 in contact with the back side 211a of the element body. In this embodiment of the rectifier element module 210, by arranging the rectifier element module 210, the substrate 20, the first conductive cooling portion 30, the second conductive cooling portion 40, and the cooling promotion portion 50 as described above, the heat generated by the substrate 20 and the first and second transistors Q1 and Q2 (rectifier elements) due to the first and second currents can be more efficiently cooled by the first conductive cooling portion 30, the second conductive cooling portion 40, and the cooling promotion portion 50. Thus, according to this embodiment, a cooling unit 200 for a rectifier element module for cooling the substrate 20 and the first and second transistors Q1 and Q2 (rectifier elements) can be provided.

[0138] Furthermore, the substrate 20 and the first conductive cooling portion 30 are in surface contact via the substrate back surface 22 and the first partial contact surface 31a. This allows the first conductive cooling portion 30 to cool the substrate 20 more efficiently than in a point contact situation. Furthermore, the first conductive cooling portion 30 and the cooling promotion portion 50 are in surface contact via the second partial contact surface 32a and the arrangement surface 51. This allows the cooling promotion portion 50 to more efficiently promote cooling of the first conductive cooling portion 30 than in a point contact situation.

[0139] In addition, the element body 211 and the second module terminal 213 are in surface contact with each other via the element body back surface 211a and one surface of the second module terminal 213, and the second module terminal 213 and the second conductive cooling part 40 are in surface contact with each other via the other surface of the second module terminal 213 and the third contact surface 40a. As a result, the element body 11 can be cooled more efficiently by the second conductive cooling part 40 than in the case of point contact. In addition, the second conductive cooling part 40 and the cooling promotion part 50 are in surface contact with each other via the fourth contact surface 40b and the configuration surface 51 via the insulating component 80. As a result, the cooling of the second conductive cooling part 40 can be promoted more efficiently by the cooling promotion part 50 than in the case of point contact. In addition, the second conductive cooling part 40 is insulated from but configured in contact with the substrate 20, so that the substrate 20 can also be cooled by the second conductive cooling part 40.

[0140] Furthermore, by suppressing heat generation in the substrate 20 and the first and second transistors Q1 and Q2 (rectifier elements), the temperature of the first and second conductive cooling units 30 and 40 is also reduced. This reduces the DC resistance Rdc of the first and second conductive cooling units 30 and 40. This reduces the conduction loss (I2Rdc, power loss), which is the product of the square of the current passing through the first and second conductive cooling units 30 and 40 and the DC resistance Rdc. This improves the power conversion efficiency of the power converter 1.

[0141] (4-2) Effects of the vertical arrangement of the substrate According to the above configuration, the module is disposed upright in a direction perpendicular to the cooling promotion portion 50. Furthermore, the first conductive cooling portion 30 on the substrate back surface 22 side and the second conductive cooling portion 40 on the substrate front surface 21 side are disposed opposite each other across the substrate 20. Thus, by attaching the first module terminal 212c to the upright substrate 20 in its standard, unbent state, a first current flowing from the first module terminal 212c through the substrate back surface 22 side can be guided through the first conductive cooling portion 30 to the secondary output (-) line Vout(-) (an example of a first external component in this embodiment), and heat generated by the first current can be cooled by the first conductive cooling portion 30. Meanwhile, a second current flowing through the second module terminal 213, disposed separately from the substrate 20 on the substrate front surface 21 side, can be guided through the second conductive cooling portion 40 to the secondary windings 2d and 2c (an example of a second external component in this embodiment), and heat generated by the second current can be cooled by the second conductive cooling portion 40.

[0142] (4-3) Effects of the Oppositeness of the First Mounting Portion and the First Conductive Cooling Portion According to the above configuration, since the first mounting portion 25 faces the first conductive cooling unit 30 across the substrate 20, the first module terminal 212c can be connected to the first conductive cooling unit 30 via the first through-current path 61 at the first mounting portion 25, without using wiring on the substrate 20. This effectively suppresses heating of the substrate 20 caused by the first current flowing through the substrate 20. Consequently, damage to the first and second transistors Q1 and Q2 (rectifier elements) caused by heating of the substrate 20 can be effectively suppressed.

[0143] (4-4) Effects of the Rectifier Element Module Constituting the Converter's Secondary Circuit In the above-described embodiment, the first external component is the output line (secondary-side output (-) line Vout(-)) on the secondary side of inverter 2, and the second external component is the secondary-side windings 2c and 2d of inverter 2. Furthermore, the rectifier element module 210 constitutes the secondary-side circuit 4 of inverter 2, and is susceptible to generating significant heat due to the large current flowing through it. As described above, since a portion of the first circuit path 60 for the first current flowing through the first and second source terminals S1 and S2 (first element terminals) is formed by the first through-current path 61, heating of the substrate 20 itself and heating of the first and second transistors Q1 and Q2 (rectifier elements) can be suppressed. Furthermore, since a portion of the first circuit path 60 is formed by the first conductive cooling portion 30, i.e., the first conductive cooling path 62, heating of the substrate 20 itself and heating of the first and second transistors Q1 and Q2 (rectifier elements) can also be suppressed. Furthermore, since a portion of the second current path 70 for the second current flowing through the first and second drain terminals D1 and D2 (second element terminals) is formed by the second conductive cooling portion 40, namely, the second conductive cooling path 72, heat generation in the substrate 20 and the first and second transistors Q1 and Q2 (rectifier elements) can be suppressed. Therefore, the cooling unit 200 for the rectifier element module described above is useful when used in the secondary circuit 4 of the inverter 2.

[0144] As another example, the following example can be cited: the first external component is a secondary-side winding of converter 2, and the second external component is an output line on the secondary side of converter 2. Furthermore, as another example, the first external component and the second external component are output lines on the secondary side of converter 2, and the polarities of the output lines are different.

[0145] 4. Variations of Implementation 2 2-1. Modification of the Rectifier Element Module Cooling Unit In the above-mentioned embodiment 1, Figure 7 and Figure 8The cooling unit 200 for the rectifier element module is described as an example. However, the cooling unit for the rectifier element module is not limited thereto, and for example, the cooling unit for the rectifier element module described below may also be used.

[0146] (1) Other methods of cooling the entire rectifier element module (1-1) Other methods 1 A cooling unit 200A for a rectifier element module according to another aspect 1 of the second embodiment of the present invention will be described. Figure 11A 200A is a side view of a cooling unit for a rectifier element module according to another embodiment 1 of the present invention. Figure 7 Compared to the rectifier module cooling unit 200 shown in FIG. 1 , the insulating member 80 is positioned differently. Only the differences are described below. In the rectifier module cooling unit 200, the insulating member 80 is positioned between the second conductive cooling unit 40, the substrate 20, and the cooling promotion unit 50. However, in the rectifier module cooling unit 200A, the insulating member 80 is positioned between the first conductive cooling unit 30, the substrate 20, and the cooling promotion unit 50. Since only the position of the insulating member 80 differs, the first conductive cooling unit 30 and the second conductive cooling unit 40 are electrically insulated from each other.

[0147] (1-2) Other methods 2 A cooling unit 200B for a rectifier element module according to another aspect 2 of the second embodiment of the present invention will be described. Figure 11B 2 is a side view of a cooling unit for a rectifier element module according to another embodiment 2 of the present invention. Figure 7 Compared to the cooling unit 200 for the rectifier element module shown in FIG, the arrangement position of the cooling promotion portion 50 differs. Only the differences are described below. In the cooling unit 200 for the rectifier element module, the first conductive cooling portion 30 and the second conductive cooling portion 40 are arranged on the arrangement surface 51 of the cooling promotion portion 50. However, in the cooling unit 200B for the rectifier element module, only the second conductive cooling portion 40 is arranged directly on the arrangement surface 51 of the cooling promotion portion 50, without intervening through the insulating member 80. The substrate 20 and the first conductive cooling portion 30 are not arranged on the arrangement surface 51. The first conductive cooling portion 30 and the second conductive cooling portion 40 are electrically insulated from each other.

[0148] (1-3) Other methods 3 A cooling unit 200C for a rectifier element module according to another aspect 3 of the second embodiment of the present invention will be described. Figure 11C200C is a side view of a cooling unit for a rectifier element module according to another embodiment of the present invention. Figure 7 The main difference from the cooling unit 200 of the rectifier element module shown is that the substrate 20 is arranged in the horizontal direction. Only the difference will be described below.

[0149] In the cooling unit 200C of the rectifier element module, a rectangular parallelepiped first conductive cooling portion 30 is disposed on the placement surface 51 of the cooling promotion portion 50. The upper surface of the first conductive cooling portion 30 is horizontal, and the substrate 20 is placed horizontally on the first conductive cooling portion 30, with the upper surface of the first conductive cooling portion 30 in surface contact with the substrate back surface 22. Furthermore, an L-shaped second conductive cooling portion 40 is disposed on the placement surface 51, with an insulating member 80 interposed therebetween. The second conductive cooling portion 40 extends upward from the portion in contact with the insulating member 80, then bends and extends to a position that overlaps the upper portion of the substrate 20. At this position, the second conductive cooling portion 40 has a fifth contact surface 40c extending along a vertical plane.

[0150] The first module terminal 212c is perpendicular to the substrate surface 21 in a standard state along the back surface 211a of the element body. Figure 11B In the example, the vertical direction (z direction) is extended. The component body 211 and the second module terminal 213 are located at a position further away from the substrate surface 21 in the vertical direction than the first module terminal 12c. At this time, the component body back surface 211a of the component body 211 is along the vertical plane. In addition, the component body 211 and the second module terminal 213 are in surface contact through the component body back surface 211a and one surface of the second module terminal 213. In addition, the second module terminal 213 and the second conductive cooling portion 40 are in surface contact through the other surface of the second module terminal 213 and the fifth contact surface 40c.

[0151] (2) Modifications of Components of the Rectifier Element Module Cooling Unit (2-1) In the second embodiment described above, the first conductive cooling portion 30 is formed into an L-shaped portion when viewed from the side, by a first portion 31 extending in a plate-like shape along the substrate back surface 22 and a second portion 32 extending in a plate-like shape along the configuration surface 51 of the cooling promotion portion 50. However, the shape of the first conductive cooling portion 30 is not limited as long as it can electrically connect the first module terminal 212c and the secondary-side output (-) line Vout(-) and cool the heat generated by the first current. For example, the first conductive cooling portion 30 may be a rectangular parallelepiped connected to the substrate back surface 22 and the configuration surface 51. In addition, the second conductive cooling portion 40 is a rectangular parallelepiped, but is not limited to this, and may also be, for example, L-shaped when viewed from the side.

[0152] (2-2) In the second embodiment described above, the first portion 31 of the first conductive cooling portion 30, extending along the substrate back surface 22, is located at the portion corresponding to the tip of the first module terminal 212c. However, the portion corresponding to the tip of the first module terminal 212c and the first portion 31 may be slightly separated, within a range that can suppress adverse effects such as damage to the rectifier element caused by heat generated by the first current. For example, the first mounting portion 25 and the first portion 31 may be slightly separated in the z-direction. In this case, wiring electrically connecting the separated portion between the first mounting portion 25 and the first portion 31 can be formed on the substrate front surface 21 or substrate back surface 22. To suppress heating of the substrate 20 caused by the passage of the first current, this wiring is preferably short.

[0153] (2-3) In the second embodiment described above, the second conductive cooling portion 40 is arranged in contact with the substrate surface 21. However, the second conductive cooling portion 40 does not need to be in contact with the substrate 20 as long as it can electrically connect the second module terminal 213 and the secondary windings 2c and 2d and cool the heat generated by the second current.

[0154] (2-4) In the second embodiment described above, the rectifier element module 210 has a three-pin structure consisting of a gate pin 212a, an unused pin 212b, and a first module terminal 212c. However, the number of pins of the rectifier element module 210 is not limited. In the second embodiment described above, the unused pins 212b are shorter than the gate pins 212a and the first module terminals 212c. However, the unused pins 212b can also be longer. Since the unused pins 212b are unused, they are inserted into the pin holes of the substrate 20 but are not electrically connected to the substrate 20 or other components.

[0155] 4. Another Example of a Power Conversion Device Including a Synchronous Rectification Circuit In the above-mentioned embodiments, the Figure 3 The power conversion device of the synchronous rectification circuit shown in FIG. 1 is taken as an example. However, the power conversion device is not limited to this, and for example, the power conversion device described below may also be used.

[0156] (1) Other Synchronous Rectification Circuits of Component 1 A power conversion device 1A including a synchronous rectification circuit of another configuration 1 will be described. Figure 12 This is a circuit diagram of a power conversion device having a synchronous rectification circuit of another configuration 1. Figure 12The power conversion device 1A shown is a midpoint tap type and includes a converter 2, a primary circuit 3, and a secondary circuit 4A. Figure 3 Compared to the power converter 1, the main differences are as follows: the first partial winding start end 2c1 and the second partial winding end 2d2 are connected to the secondary-side output (+) line Vout(+) via the secondary-side circuit 4A, and the connection between the first partial winding end 2c2 and the second partial winding start end 2d1 is connected to the secondary-side output (-) line Vout(-). The rest of the structure of the power converter 1A is identical to that of the power converter 1. The following description focuses on the differences.

[0157] The first drain terminal D1 and the second drain terminal D2 are connected to the secondary side output (+) line Vout (+) (at Figure 12 The first source terminal S1 and the second source terminal S2 are connected to the secondary windings 2c and 2d (in the structure of Figure 12 (an example of a first external component in the configuration). Specifically, the first source terminal S1 is connected to the first partial winding start end 2c1, and the second source terminal S2 is connected to the second partial winding end end 2d2. The first gate signal g1 and the second gate signal g2 are input to the third gate terminal G3 and the fourth gate terminal G4, respectively. The first transistor and the second transistor Q1 and Q2 are included in different rectifier element modules 10 or rectifier element modules 210 , respectively, similarly to the above-mentioned embodiments.

[0158] When the first transistor Q1 is on and the second transistor Q2 is off, a signal from the secondary-side output (-) line Vout(-) is supplied to the first partial winding end 2c2 of the first partial winding 2c. The output voltage induced in the first partial winding 2c flows as a first current from the first partial winding start 2c1 via a first circuit path 60 comprising a first through-current path 61 and a first conductive cooling path 62 to the first source terminal S1. Furthermore, a second current flows from the first drain terminal D1 via a second current path 70 comprising a second through-current path 71 and a second conductive cooling path 72, resulting in an output voltage being output from the secondary-side output (+) line Vout(+).

[0159] On the other hand, when the second transistor Q2 is on and the first transistor Q1 is off, a signal from the secondary-side output (-) line Vout(-) is supplied to the second partial winding start end 2d1 of the second partial winding 2d. The output voltage induced in the second partial winding 2d flows as a first current from the second partial winding end end 2d2 via a first circuit path 60 comprising a first through-current path 61 and a first conductive cooling path 62 to the second source terminal S2. Furthermore, a second current flows from the second drain terminal D2 via a second current path 70 comprising a second through-current path 71 and a second conductive cooling path 72, resulting in an output voltage being output from the secondary-side output (+) line Vout(+).

[0160] (2) Other Synchronous Rectification Circuits of Component 2 A power conversion device 1B including a synchronous rectification circuit of another configuration 2 will be described. Figure 13 2 is a circuit diagram of a power conversion device having a synchronous rectification circuit of another configuration 2. Figure 13 The power conversion device 1B shown is a full-bridge type, and includes a converter 2, a primary circuit 3, and a secondary circuit 4B. Figure 3 Compared to the power converter 1, the main difference is that the secondary winding 2e is provided instead of the secondary windings 2c and 2d, and the secondary circuit 4B is structured differently. The rest of the structure of the power converter 1B is the same as that of the power converter 1. The following will focus on the differences.

[0161] Secondary-side circuit 4B includes first, second, and fourth transistors Q1, Q4. The first and fourth transistors Q1, Q4, and the second and third transistors Q2, Q3, are alternately turned on and off. The first and second transistors Q1, Q2 are connected in series, with their first source terminal S1 connected to their second drain terminal D2. Furthermore, the third and fourth transistors Q3, Q4 are connected in series, with their third source terminal S3 connected to their fourth drain terminal D4.

[0162] The first drain terminal D1 is connected to the secondary side output (+) line Vout(+) (at Figure 13 The first source terminal S1 is connected to the secondary winding 2e (in the structure of the second external component). Figure 13 Specifically, the first source terminal S1 is connected to the secondary winding start end 2e1. The first gate terminal G1 receives a first gate signal g1.

[0163] The second drain terminal D2 is connected to the secondary winding 2e (at Figure 13Specifically, the second drain terminal D2 is connected to the secondary winding start end 2e1. The second source terminal S2 is connected to the secondary side output (-) line Vout (-) (in Figure 13 The second gate terminal G2 is input with a second gate signal g2.

[0164] The third drain terminal D3 is connected to the secondary side output (+) line Vout (+) (at Figure 13 The third source terminal S3 is connected to the secondary winding 2e (in the structure of the second external component). Figure 13 Specifically, the third source terminal S3 is connected to the secondary winding end 2e2. The second gate signal g2 is input to the third gate terminal G3.

[0165] The fourth drain terminal D4 is connected to the secondary winding 2e (at Figure 13 Specifically, the fourth drain terminal D4 is connected to the secondary winding end 2e2. The fourth source terminal S4 is connected to the secondary output (-) line Vout (-) (in Figure 13 The first gate signal g1 is input to the fourth gate terminal G4. The first to fourth transistors Q1 to Q4 are included in different rectifier element modules 10 or rectifier element modules 210 , respectively, similarly to the above-described embodiments.

[0166] When the first and fourth transistors Q1 and Q4 are on and the second and third transistors Q2 and Q3 are off, a signal from the secondary output (-) line Vout(-) is transmitted as a first current via a first circuit path 60 comprising a first through-current path 61 and a first conductive cooling path 62 to the fourth source terminal S4, and the current flows from the fourth source terminal S4 to the fourth drain terminal D4. Furthermore, a second current flows from the fourth drain terminal D4 to the secondary winding end 2e2 of the secondary winding 2e via a second current path 70 comprising a second through-current path 71 and a second conductive cooling path 72. The output voltage induced in the secondary winding 2e is transmitted as a first current from the secondary winding start 2e1 to the first source terminal S1 via the first circuit path 60 comprising the first through-current path 61 and the first conductive cooling path 62, and the current flows from the first source terminal S1 to the first drain terminal D1. Then, the second current flows from the first drain terminal D1 through the second current path 70 including the second through-current path 71 and the second conductive cooling path 72 , and is output as an output voltage from the secondary-side output (+) line Vout(+).

[0167] On the other hand, when the second and third transistors Q2 and Q3 are on and the first and fourth transistors Q1 and Q4 are off, the signal from the secondary output (-) line Vout(-) is transmitted as a first current via a first circuit path 60 comprising a first through-current path 61 and a first conductive cooling path 62 to the second source terminal S2, and the current flows from the second source terminal S2 to the second drain terminal D2. Furthermore, a second current flows from the second drain terminal D2 to the secondary winding start end 2e1 of the secondary winding 2e via a second current path 70 comprising a second through-current path 71 and a second conductive cooling path 72. The output voltage induced in the secondary winding 2e is transmitted as a first current from the secondary winding end end 2e2 to the third source terminal S3 via the first circuit path 60 comprising the first through-current path 61 and the first conductive cooling path 62, and the current flows from the third source terminal S3 to the third drain terminal D3. Then, the second current flows from the third drain terminal D3 through the second current path 70 including the second through-current path 71 and the second conductive cooling path 72 , and is output as an output voltage from the secondary-side output (+) line Vout(+).

[0168] (3) Other synchronous rectification circuits of component 3 A power conversion device 1C including a synchronous rectification circuit having another configuration 3 will be described. Figure 14 This is a circuit diagram of a power conversion device having a synchronous rectification circuit of another configuration 3. Figure 14 The illustrated power converter 1C is a forward-type device comprising a converter 2, a primary circuit 3, and a secondary circuit 4C. Power converter 1C primarily features a secondary winding 2e in place of secondary windings 2c and 2d, and differs in the connections between secondary winding 2e and first and second transistors Q1 and Q2. The remainder of the configuration of power converter 1C is identical to power converter 1. The following description focuses on the differences.

[0169] The first drain terminal D1 is connected to the secondary side output (+) line Vout (+) (at Figure 14 The first source terminal S1 is connected to the secondary winding 2e (in the structure of the second external component). Figure 14 Specifically, the first source terminal S1 is connected to the secondary winding start end 2e1. The first gate terminal G1 receives a first gate signal g1.

[0170] The second drain terminal D2 is connected to the secondary side output (+) line Vout (+) (at Figure 14 The second source terminal S2 is connected to the secondary winding 2e (in the structure of the second external component). Figure 14An example of a first external component in the configuration) and a secondary side output (-) line Vout(-) (in Figure 14 Specifically, the second source terminal S2 is connected to the secondary winding end 2e2 and the secondary output (-) line Vout(-). The second gate terminal G2 receives a second gate signal g2. The first transistor and the second transistor Q1 and Q2 are included in different rectifier element modules 10 or rectifier element modules 210 , respectively, similarly to the above-mentioned embodiments.

[0171] When the first transistor Q1 is on and the second transistor Q2 is off, a signal from the secondary output (-) line Vout(-) is supplied to the secondary winding end 2e2 of the secondary winding 2e. The output voltage induced in the secondary winding 2e flows as a first current from the secondary winding start 2e1 via a first circuit path 60 comprising a first through-current path 61 and a first conductive cooling path 62 to the first source terminal S1. Current then flows from the first source terminal S1 to the first drain terminal D1. Furthermore, a second current flows from the first drain terminal D1 via a second current path 70 comprising a second through-current path 71 and a second conductive cooling path 72, resulting in an output voltage being output from the secondary output (+) line Vout(+).

[0172] On the other hand, when the second transistor Q2 is turned on and the first transistor Q1 is turned off, the secondary side output (−) line Vout(−) and the secondary side output (+) line Vout(+) are conductive via the second transistor Q2 .

[0173] (4) Other synchronous rectification circuits of component 4 A power conversion device 1D including a synchronous rectification circuit having another configuration 4 will be described. Figure 15 This is a circuit diagram of a power conversion device having a synchronous rectification circuit of another configuration 4. Figure 15 The power conversion device 1D shown is a forward type, and includes a converter 2, a primary circuit 3, and a secondary circuit 4D. Figure 14 Compared to the power converter 1C, the main difference is the connection between the secondary winding 2e and the first and second transistors Q1 and Q2. The rest of the structure of the power converter 1D is the same as that of the power converter 1C. The following will focus on the differences.

[0174] The first drain terminal D1 is connected to the secondary winding 2e (at Figure 15 Specifically, the first drain terminal D1 is connected to the secondary winding end 2e2. The first source terminal S1 is connected to the secondary output (-) line Vout (-) (in Figure 15 The first gate terminal G1 receives a first gate signal g1.

[0175] The second drain terminal D2 is connected to the secondary side output (+) line Vout (+) (at Figure 15 An example of a second external component in the structure) and a secondary winding 2e (in Figure 15 Specifically, the second drain terminal D2 is connected to the secondary side output (+) line Vout(+) and the secondary side winding start end 2e1. The second source terminal S2 is connected to the secondary side output (-) line Vout(-) (in Figure 15 The second gate terminal G2 is input with a second gate signal g2. The first transistor and the second transistor Q1 and Q2 are included in different rectifier element modules 10 or rectifier element modules 210 , respectively, similarly to the above-mentioned embodiments.

[0176] When the first transistor Q1 is on and the second transistor Q2 is off, the signal from the secondary output (-) line Vout(-) is transmitted as a first current via a first circuit path 60 comprising a first through-current path 61 and a first conductive cooling path 62 to the first source terminal S1, and the current flows from the first source terminal S1 to the first drain terminal D1. A second current flows from the first drain terminal D1 via a second current path 70 comprising a second through-current path 71 and a second conductive cooling path 72, and is supplied to the secondary winding end 2e2 of the secondary winding 2e. The output voltage induced in the secondary winding 2e is then output from the secondary winding start 2e1 to the secondary output (+) line Vout(+).

[0177] On the other hand, when the second transistor Q2 is turned on and the first transistor Q1 is turned off, the secondary side output (−) line Vout(−) and the secondary side output (+) line Vout(+) are conductive via the second transistor Q2 .

[0178] (5) Rectifier circuit In each of the above-mentioned embodiments, the secondary side circuit 4 includes a synchronous rectifier circuit using a first transistor and a second transistor Q1 and Q2. However, as long as the secondary side circuit 4 can rectify the output voltage induced in the secondary side windings 2c and 2d, it may also include a rectifier circuit instead of a synchronous rectifier circuit. In the rectifier circuit, for example, a diode (an example of a rectifier element) is included as a rectifier element instead of the first transistor and the second transistor Q1 and Q2. The diode has an anode (an example of a first element terminal) and a cathode (an example of a second element terminal), and the current flows in the forward direction from the anode to the cathode, and the current does not flow in the reverse direction from the cathode to the anode. Thus, the diode performs a switching action based on the voltage difference applied to the anode and the cathode. The output voltage rectified by the rectification action of the diode can be used as the output of the rectifier circuit.

[0179] Specifically, for example, Figure 16 The rectifier circuit shown. Figure 16 This is a circuit diagram of a power conversion device having a rectifier circuit. exist Figure 16 In the embodiment, as diodes, a first diode d1 (an example of a rectifier element) is provided instead of the first transistor Q1, and a second diode d2 (an example of a rectifier element) is provided instead of the second transistor Q2. The first diode d1 has a first anode A1 (equivalent to Figure 3 The first source terminal S1) and the first cathode K1 (equivalent to Figure 3 The second diode d2 has a second anode A2 (equivalent to a first drain terminal D1). Figure 3 The second source terminal S2) and the second cathode K2 (equivalent to Figure 3 The first and second anodes A1 and A2 are connected to the secondary-side output (-) line Vout(-). The first and second cathodes K1 and K2 are connected to the secondary-side windings 2c and 2d. Specifically, the first cathode K1 is connected to the end of the second partial winding 2d2, and the second cathode K2 is connected to the start of the first partial winding 2c1. Alternating current flows through the first and second diodes d1 and d2, resulting in a rectified output voltage that is output from the secondary-side output (+) line Vout(+).

[0180] Furthermore, as described above, although the embodiments of the present invention have been disclosed through the above description, the present invention is not limited thereto.

[0181] In each of the above-mentioned embodiments, the rectifier element module is a rectifier element module 10 as a surface-mounted component or a rectifier element module 210 as a separate component. However, the rectifier element module of the present invention only needs to include a rectifier element having a rectifying function and is not limited by the specific structure for realizing this function or the specific content of the module installation form relative to the substrate.

[0182] In addition, in embodiment 1, the second module terminal 13 is connected to the second current path 70 via the back surface 11a of the element body opposite to the substrate surface 21, and the first module terminal 12c extends from the surface of the element body 11 other than the back surface 11a of the element body along the substrate surface 21 and is connected to the first circuit path 60, but the connection between the second module terminal 13 and the second current path 70, and the connection between the first module terminal 12c and the first circuit path 60 are not limited to this, and any method can be used.

[0183] In addition, in embodiment 2, the second module terminal 13 is connected to the second current path 70 via the back surface 11a of the element body opposite to the substrate surface 21, and the first module terminal 12c extends from the surface of the element body 11 other than the back surface 11a of the element body toward the substrate surface and is connected to the first circuit path 60, but the connection between the second module terminal 13 and the second current path 70, and the connection between the first module terminal 12c and the first circuit path 60 are not limited to this, and any method can be used.

[0184] In the second embodiment, the second conductive cooling path 72 is provided to pass through the second conductive cooling portion 40 instead of the substrate 20 , but may also pass through the substrate 20 .

[0185] That is, various changes can be made to the mechanism, shape, material, number, position, arrangement, etc. of the above-described embodiment without departing from the scope of the technical concept and purpose of the present invention, and these are also included in the present invention. Description of the label

[0186] 1. 1A~1D: Power conversion device 2: Converter 2a: Core 2b: Primary winding 2c, 2d, 2e: Secondary winding 3: Primary side circuit 4. 4A~4D: Secondary side circuit 10, 210: Rectifier component module 11, 211: Component body 11a, 211a: Back side of component body 11b, 211b: front surface of the component body 11c, 211c: Side of the component body 12, 212: First lead terminal 12a, 212a: Gate pins 12b, 212b: Unused pins 12c, 212c: First module terminal 13, 213: Second module terminal 20: Substrate 21:Substrate surface 22: Back side of substrate 25: First installation part 26: Second installation part 27, 28: First through-piece, second through-piece 30, 40: first conductive cooling part, second conductive cooling part 50: Cooling promotion department 51: Configuration interface 60: First circuit path 61: First through-current path 62: First conductive cooling path 70: Second current path 71: Second through-current path 72: Second conductive cooling path 80: Insulation parts 100, 200, 100A~100C, 200A~200C: Cooling unit for rectifier element module A1, A2: first anode, second anode D1 to D4: First drain terminal to fourth drain terminal (second element terminal) G1 to G4: First to fourth gate terminals K1, K2: first cathode, second cathode Q1 to Q4: First to fourth transistors (rectifier elements) S1 to S4: First source terminal to fourth source terminal (first element terminal) Vin(+): Primary side input (+) line Vin(-): Primary side input (-) line Vout(+): Secondary side output (+) line Vout(-): Secondary side output (-) line d1, d2: first diode, second diode g1, g2: first gate signal, second gate signal

Claims

1. A cooling unit for a rectifier element module, It has: A rectifier element module having an element body in which a rectifier element having a first element terminal and a second element terminal is disposed, a first module terminal electrically connected to the first element terminal, and a second module terminal electrically connected to the second element terminal; A substrate formed in a plate shape, having a substrate surface and a substrate back surface, wherein the rectifying element module is arranged on the substrate surface side; a first conductive cooling portion for electrically connecting a first external component disposed outside the cooling unit relative to the rectifier element module and the first module terminal, and mainly cooling heat generated by a first current passing through the first element terminal; a second conductive cooling portion for electrically connecting a second external component disposed outside the cooling unit relative to the rectifier element module and the second module terminal, and mainly cooling heat generated by a second current passing through the second element terminal; as well as A conductive cooling promotion part has a configuration surface for configuring the first conductive cooling part and the second conductive cooling part, is electrically connected to one of the first conductive cooling part and the second conductive cooling part via the configuration surface, and is insulatedly connected to the other, and is used to promote cooling of the first conductive cooling part and the second conductive cooling part. A portion of a first circuit path of the first current from the first element terminal via the first module terminal and the first conductive cooling portion to the first external component is formed by a first through-current path penetrating the substrate from the substrate surface to the substrate back surface.

2. The cooling unit for the rectifier element module according to claim 1, wherein: A portion of a second current path of the second current that reaches the second external component from the second element terminal via the second module terminal and the second conductive cooling portion is formed by a second through-current path that penetrates the substrate from the substrate surface to the substrate back surface.

3. The cooling unit for the rectifier element module according to claim 2, wherein: The rectifier element module is surface mounted on the surface of the substrate via the back surface of the element body. The second module terminal is connected to the second current path via the back surface of the element body opposite to the surface of the substrate, The first module terminal extends from a surface of the component body other than the rear surface of the component body along the substrate surface and is connected to the first circuit path.

4. The cooling unit for the rectifier element module according to claim 1, wherein: A part of a second current path of the second current from the second element terminal via the second module terminal and the second conductive cooling portion to the second external member is constituted by a second conductive cooling path passing through the second conductive cooling portion without passing through the substrate.

5. The cooling unit for the rectifier element module according to claim 4, wherein: The rectifier element module is mounted on the surface of the substrate. The second module terminal is connected to the second current path via the back surface of the element body opposite to the second conductive cooling portion, The first module terminal extends from a surface of the component body other than the rear surface of the component body along the substrate surface and is connected to the first circuit path.

6. The cooling unit for the rectifier element module according to claim 1, wherein: The first conductive cooling portion and the second conductive cooling portion are formed as a busbar.

7. The cooling unit for the rectifier element module according to claim 1, wherein: The substrate is arranged in a state where the substrate front surface and the substrate back surface are parallel to the cooling promoting portion.

8. The cooling unit for the rectifier element module according to claim 1, wherein: The substrate is erected in a state where the substrate front surface and the substrate back surface are in a vertical direction with respect to the cooling promotion portion.

9. The cooling unit for a rectifier element module according to claim 1 or 2, wherein: The first module terminal is mounted on a first mounting portion of the substrate and is opposed to at least a portion of the first conductive cooling portion via the substrate.

10. The cooling unit for a rectifier element module according to claim 1 or 2, wherein: The second module terminal is mounted on a second mounting portion of the substrate and is opposed to at least a portion of the second conductive cooling portion via the substrate.

11. The cooling unit for a rectifier element module according to claim 1 or 2, wherein: The first external component is at least one of a secondary winding of the converter and an output line of the secondary side of the converter, and the second external component is at least one of a secondary winding of the converter and an output line of the secondary side of the converter.

12. The cooling unit for a rectifier element module according to claim 1 or 2, wherein: The rectifying element is a transistor, The first element terminal and the second element terminal are respectively one of a drain terminal and a source terminal of the transistor.

13. The cooling unit for a rectifier element module according to claim 1 or 2, wherein: The rectifying element is a diode, The first element terminal and the second element terminal are respectively one of an anode and a cathode of the diode.

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