JP2019154124A - Semiconductor module terminal connection structure - Google Patents

Abstract

To provide a terminal connection structure of a semiconductor module capable of preventing or inhibiting a bus bar from floating by restraining the bus bar to an insulator.SOLUTION: In a terminal connection structure of a semiconductor module connecting via bus bars 5, 6 a positive electrode terminal 2b and a negative electrode terminal 2c, protruding in the same direction from each of a plurality of semiconductor modules 2 and a predetermined connection target component 4, each of the bus bar 5, 6 has a flat plate portion and a bonding portion that is bent in the same direction from the plate portion and is bonded to a positive electrode side terminal 2b or a negative electrode side terminal 2c, The bus bars 5, 6 are arranged in order of the plate portion of any one of the bus bars 5, an insulator 7, and the plate portion of the other bus bar 6 along the protruding direction of the terminals 2b and 2c from the semiconductor module 2 side.The other bus bar 6 is provided with a restraining portion 6d that engages with the insulator 7 so that the bus bar is not displaced to a side away from the insulator 7 with respect to a protruding direction of the terminals 2b, 2c.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a terminal connection structure in which a positive terminal and a negative terminal of each of a plurality of semiconductor modules are connected to a connection target via a bus bar.

  In a power conversion device including an inverter circuit, a converter circuit, and the like, a plurality of semiconductor modules that are also called power semiconductors are mounted. The semiconductor module is appropriately connected to a connection target component such as a capacitor, but as a structure for realizing the connection, a plurality of semiconductor modules are arranged in a line so that each positive terminal and negative terminal protrude in the same direction. Stacked side by side, a pair of bus bar plate portions are stacked on the semiconductor module row so that an insulator is sandwiched between them, and a junction raised from one bus bar plate portion is connected to the positive terminal of each semiconductor module. A terminal connection structure is known in which a joint raised from the plate of the other bus bar is joined to the negative terminal of each semiconductor module (see, for example, Patent Document 1).

JP 2017-2112810 A

  In the structure in which the plate portions of the pair of bus bars are overlapped with the insulator interposed therebetween, there is a possibility that inconvenience may occur due to the bus bar arranged on the opposite side of the semiconductor module with respect to the insulator floating from the insulator. For example, in a structure in which bus bars are arranged in parallel at a minimum distance, an inductance reduction effect due to mutual inductance can be expected, but if the bus bar rises, the distance between the plate portions may increase, and the inductance reduction effect may be impaired. Alternatively, the contact area between the plate portion and the insulator may be reduced due to the rise of the bus bar, and the insulation may be deteriorated.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a terminal connection structure of a semiconductor module that can restrain or suppress the bus bar from being lifted by restraining the bus bar with an insulator.

  The terminal connection structure which concerns on 1 aspect of this invention is a semiconductor which connects the positive electrode terminal and negative electrode terminal which protrude in the same direction from each of several semiconductor modules, and predetermined connection object components via a positive electrode side bus bar and a negative electrode side bus bar. A terminal connection structure for a module, wherein each of the positive-side bus bar and the negative-side bus bar has a flat plate portion that extends flatly and is bent in the same direction from the plate portion and joined to the positive-side terminal or the negative-side terminal. Each of the positive electrode side bus bar and the negative electrode side bus bar is provided along the protruding direction of the positive electrode terminal and the negative electrode terminal from the plurality of semiconductor module sides, The insulator and the plate portion of the other bus bar overlap in this order, and the joint portion of the positive side bus bar is connected to the positive terminal, and the joint portion of the negative side bus bar is the negative side. Each of the other bus bars is provided with a restraining portion that engages with the insulator so that the other bus bar is not displaced to the side away from the insulator in the protruding direction. Is.

The perspective view which shows an example of the power converter device to which the terminal connection structure which concerns on one form was applied. The perspective view which shows the detail of the laminated part of a pair of bus bar and an insulator. FIG. 3 is a vertical sectional view showing a state in which the enlarged portion shown in FIG. 2 is viewed along the Y direction of FIG. 1. FIG. 3 is a vertical sectional view showing a state in which the enlarged portion shown in FIG. 2 is viewed along the X direction of FIG. 1. The figure which shows a mode that the negative electrode side bus bar is mounted | worn with an insulator. The figure which shows the state by which the negative electrode side bus bar was mounted | worn with the insulator. The figure which shows the original stamped out as a foundation which forms a negative electrode side bus bar. The perspective view which shows the primary intermediate product formed based on the original plate of FIG. The perspective view which shows the secondary intermediate product formed based on the original plate of FIG. The perspective view which shows the final shape of a negative electrode side bus bar. The figure which shows the modification of FIG. The figure which shows the modification of FIG.

  An embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows an example of a power converter to which the terminal connection structure of this embodiment is applied. The illustrated power conversion apparatus 1 is incorporated in, for example, a power control unit of an electric vehicle, boosts a voltage applied from a vehicle battery, or steps down a voltage applied from an electric motor, and DC power and AC power. And a drive circuit such as an inverter circuit in charge of conversion. The circuit configuration may be appropriate, and a detailed description thereof will be omitted. The power converter 1 includes a plurality of semiconductor modules 2 arranged in a line, a cooler 3 that cools the semiconductor modules 2, a capacitor 4 as an example of a connection target component of each semiconductor module 2, and each semiconductor A pair of bus bars 5 and 6 for connecting the module 2 and the capacitor 4 and an insulator 7 interposed between the bus bars 5 and 6 are provided. Note that the plurality of semiconductor modules 2 have the same configuration, and in FIG. 1, only a part of them is represented by reference numerals. In the same manner, a plurality of elements having the same configuration may be given a reference symbol on behalf of only some elements. Further, in the following, when specifying the direction in the power conversion device 1, as shown in FIG. 1, the alignment direction of the semiconductor modules 2 is the X direction, and the vertical direction orthogonal to the alignment direction is the Z direction, the X direction, and the Z direction. A direction orthogonal to both of the directions is sometimes referred to as a Y direction, and the direction in each direction may be referred to as a positive direction, and a negative direction may be referred to as a negative direction. However, these names are set for convenience of explanation.

  As an example, the semiconductor module 2 is configured as a switching element for power conversion in a converter circuit or an inverter circuit. Such a semiconductor module 2 is sometimes called a power semiconductor. Each semiconductor module 2 has a flat card-like package 2a in which elements such as transistors and diodes constituting a switching element are enclosed, for example, a rectangular card-like package 2a. From one side of the package 2a, a positive terminal 2b The negative terminal 2c and the midpoint terminal 2d are drawn out so as to protrude in the same direction (Z positive direction in FIG. 1). The terminals 2b, 2c, and 2d are formed as a flat plate parallel to the front and back surfaces of the package 2a of the semiconductor module 2 as an example, and the arrangement direction of the terminals 2b, 2c, and 2d is parallel to the side direction of the package 2a.

  The cooler 3 includes a plurality of flat plate-like heat exchange units 3a arranged in parallel with each other in the X direction in FIG. 1 and a pair of refrigerants such as cold water flowing through the heat exchange units 3a. A refrigerant pipe 3b is provided. The refrigerant flows from one of the refrigerant pipes 3b and is discharged from the other refrigerant pipe 3b. The number of heat exchange parts 3a is set to be one more than that of the semiconductor module 2. The semiconductor modules 2 are arranged one by one in the gap between the heat exchanging portions 3a with the protruding directions of the terminals 2b, 2c, and 2d aligned in the same direction, for example, the positive Z direction in FIG. 1 are arranged in a line in the X direction. The bus bars 5 and 6 and the insulator 7 are arranged on the upper surface side (the Z positive direction side) of the cooler 3 so as to overlap one bus bar 5, the insulator 7 and the other bus bar 6 in this order. The lower bus bar 5 connects the positive terminal 2 b of each semiconductor module 2 and the capacitor 4, and the upper bus bar 6 connects the negative terminal 2 c of each semiconductor module 2 and the capacitor 4. Hereinafter, the bus bar 5 may be referred to as a positive electrode side bus bar 5, and the bus bar 6 may be referred to as a negative electrode side bus bar 6. Note that description of the connection destination of the midpoint terminal 2d is omitted.

  Details of the laminated portion of the bus bars 5 and 6 and the insulator 7 are shown in FIGS. 2 is a partially enlarged view of FIG. 1, and FIGS. 3 and 4 are vertical sectional views of the enlarged portion shown in FIG. 2, in which the positive electrode terminal 2b and the negative electrode terminal 2c are not shown. Yes. First, as shown in FIGS. 3 and 4, the positive-side bus bar 5 is schematically shown in the same direction (Z positive direction) from the plate portion 5 a that extends flatly along the lower surface side of the insulator 7. And a plurality of joint portions 5b bent by 90 °. Each of the joint portions 5b is provided in one-to-one correspondence with the positive electrode terminal 2b of the semiconductor module 2, the number of the joint portions 5b is equal to the number of the positive electrode terminals 2b, and the interval in the arrangement direction is the interval between the positive electrode terminals 2b. Is equal to Thereby, when the positive electrode side bus bar 5 is arranged on the cooler 3, each joint portion 5 b comes into contact with the positive electrode terminal 2 b so as to face each positive electrode terminal 2 b of the semiconductor module 2.

  The negative electrode-side bus bar 6 includes a plate portion 6a that extends flatly along the upper surface side of the insulator 7, and a plurality of joint portions 6b that bend approximately 90 ° in the same direction from the plate portion 6a. Each of the joint portions 6b is provided in one-to-one correspondence with the negative electrode terminal 2c of the semiconductor module 2, the number of the joint portions 6b is equal to the number of the negative electrode terminals 2c, and the interval in the arrangement direction is the interval between the negative electrode terminals 2c. Is equal to Thereby, when the negative electrode side bus bar 6 is disposed on the insulator 7, each joint 6 b comes into contact with the negative electrode terminal 2 c so as to face each negative electrode terminal 2 c of the semiconductor module 2. The plate portions 5a and 6a are generally formed in a single flat plate shape, but a part of each is folded 180 °. Therefore, in FIG.3 and FIG.4, each of plate part 5a, 6a is shown by the flat plate shape of 2 sheets (refer the referential mark 5 and 6 of FIG. 4).

  The insulator 7 is made of an insulating material such as a resin. As well shown in FIG. 3, the insulator 7 is provided with a flat plate-like base portion 7a and a hollow cylindrical portion 7b protruding from the base portion 7a in the same direction (Z positive direction). A bus bar mounting groove 7c into which the positive electrode side bus bar 5 is fitted is formed in the base portion 7a. A thin plate portion 7d is formed in the base portion 7a by the bus bar mounting groove 7c. When the plate portions 5a and 5b of the bus bars 5 and 6 face each other across the thin plate portion 7d, the parallel running effect between the bus bars 5 and 6 increases, and the inductance reduction effect due to mutual inductance increases. The cylindrical part 7 b is a part through which the positive electrode terminal 2 b and the joint part 5 b of the positive electrode side bus bar 5 pass. The number of tube portions 7b is equal to the number of positive electrode terminals 2b and joint portions 5b, and the arrangement interval of the cylinder portions 7b is the same as the arrangement interval of the positive electrode terminals 2b and the joint portions 5b. In the negative electrode side bus bar 6, a hole 6 c for passing each cylindrical portion 7 is formed.

  As shown in FIG. 3, in the base portion 7a of the insulator 7, a latching portion 7e and a groove portion 7f are provided at an end portion on the opposite side of the bus bar mounting groove 7c. On the other hand, as shown in FIG. 2, a plurality of claw portions 6 d are formed at one end portion (end portion in the Y positive direction in FIG. 1) of the negative electrode side bus bar 6. Each claw portion 6d is provided as an example of a restraining portion that meshes with the insulator 7 so that the negative-side bus bar 6 does not displace to the side away from the insulator 7 in the protruding direction of the terminals 2b and 2c of the semiconductor module 2. That is, as shown by the arrow F in FIG. 5, when the negative-side bus bar 6 is put on the base portion 7a from above the insulator 7, the claw portion 6d gets over the hook portion 7e of the base portion 7a and fits into the groove portion 7f. The front end side of the claw portion 6d has a shape folded back by 180 ° and has an increased thickness. Accordingly, when the claw portion 6d fits into the groove portion 7f, the claw portion 6d engages with the latching portion 7e in the projecting direction of the terminals 2b and 2c (Z positive direction in FIG. 1), whereby the claw portion 6d becomes the terminal 2b. 2c is restrained by the insulator 7 so that relative displacement is impossible in the protruding direction. For this reason, the negative side bus bar 6 is prevented from floating. If the negative electrode side bus bar 6 is lifted from the insulator 7, the distance between the plate portions 5a, 6a of the bus bars 5, 6 is increased, and the above-described inductance reduction effect is impaired, or the negative electrode side bus bar 6 and the insulator 7 There is a possibility that inconveniences such as reduction of the contact area of the metal and reduction in insulation may occur, but the occurrence of such inconvenience is suppressed by preventing the negative side bus bar 6 from being lifted by the claw portion 6d, Alternatively, it can be prevented. In FIG. 5, the negative-side bus bar 6 is moved downward and mounted on the insulator 7 in order to allow the cylindrical portion 7b of the insulator 7 to pass through the hole 6c. That is, since the cylindrical portion 7b penetrates the punched hole 6c, it is difficult or impossible to displace the negative electrode bus bar 6 in the direction along the surface of the plate portion 6a with respect to the insulator 7. Therefore, the claw portion 6d is also configured to be able to get over the hook portion 7e and fit into the groove portion 7f when the insulator 7 is mounted from above. The end of each bus bar 5, 6 on the side of the capacitor 4 is appropriately restrained at, for example, a joint portion with the capacitor 4. Therefore, if the end of the negative side bus bar 6 on the opposite side (Y positive direction in FIG. 1) is constrained by the claw portion 6d, the floating of the negative side bus bar 6 can be sufficiently suppressed.

  Next, an example of a procedure for forming the negative electrode bus bar 6 will be described with reference to FIGS. In order to form the negative electrode side bus bar 6, first, as shown in FIG. 7, an original plate 6 </ b> A of the negative electrode side bus bar 6 is formed by punching one conductive metal plate. In the original plate 6A, the joint portion 6b and the punching hole 6c are punched to be formed flush with the plate portion 6a. However, the joining portions 6b are formed in a staggered manner over two rows. In each row of the joint portions 6b, the arrangement interval of the junction portions 6b is twice the arrangement interval of the junction portions 6b in the negative electrode bus bar 6 of the final product. Further, claw portions 6d are formed at two positions between the rows of the joint portions 6b so as to be flush with the plate portion 6a. Next, as illustrated by an arrow B in FIG. 8, the outer row joining portion 6b is bent downward by approximately 90 °, and the inner row joining portion 6b is bent upward by approximately 90 °. Thereby, the primary intermediate product 6B is formed. Thereafter, the joint 6b in the outer row is folded back 180 ° along the broken line FL-FL set in the middle between the rows of the joint 6b (see arrow C). Thereby, the secondary intermediate product 6C shown in FIG. 9 is formed. The folded portion at this time may be joined to the plate portion 6a by welding or the like. In the secondary intermediate product 6 </ b> C, the joint portions 6 b are aligned in a line, and the distance between the joint portions 6 b coincides with the distance between the joint portions 6 b in the negative-side bus bar 6. The claw portion 6d is maintained in an extended state so as to be flush with the plate portion 6a. Thereafter, as indicated by an arrow D in FIG. 9, the claw portion 6d of the secondary intermediate product 6C is bent downward. Specifically, the front end side of the claw portion 6d is bent downward by approximately 180 °, and the base portion side of the claw portion 6d is bent downward by approximately 90 °. Further, both ends of the plate portion 6a are also folded as necessary. Thereby, the negative electrode side bus bar 6 shown in FIG. 10 is formed.

  The present invention is not limited to the above-described embodiments and modifications, and may be implemented in various modified or changed forms. For example, in the above embodiment, the claw portion 6d of the negative electrode side bus bar 6 is formed into a predetermined shape in advance before being attached to the insulator 7, but for example, as shown in FIGS. The claw part 6d may be engaged with the latching part 7e by bending the claw part 6d along the latching part 7e as shown by the arrow E in FIG. . In addition to this, the restraining portion for preventing the bus bar from being lifted up may be provided at an appropriate position of the bus bar, and its shape can be appropriately modified as long as the displacement of the bus bar toward the side away from the insulator can be suppressed. . For example, a through hole is formed in the base portion of the insulator 7 (excluding the range of the thin plate portion 7d), and the negative electrode is formed by fitting a boss, a pin, or the like, which is integral with the negative electrode bus bar 6, into the through hole. The side bus bar 6 may be prevented from floating.

  In the above embodiment, the lifting of the negative bus bar 6 from the insulator 7 corresponding to the structure in which the positive bus bar 5, the insulator 7, and the negative bus bar 6 are overlapped in this order as viewed from the row of the semiconductor modules 2 is the restraining portion. In the case where the negative side bus bar is disposed between the semiconductor module and the insulator and the positive side bus bar is disposed above the insulator, the positive side bus bar is lifted. May be restrained by the restraining portion.

  The terminal connection structure according to the present invention is not limited to an example applied to a power conversion device for an electric vehicle, but is a terminal connection structure when a positive electrode terminal and a negative electrode terminal of a semiconductor module are connected to a component to be connected by a bus bar. May be used for various purposes.

  Various aspects of the present invention derived from each of the above-described embodiments and modifications will be described below. In the following description, in order to facilitate understanding of each aspect of the present invention, the corresponding components illustrated in the accompanying drawings are added in parentheses, but the present invention is thereby limited to the illustrated embodiments. It is not something.

  The terminal connection structure which concerns on 1 aspect of this invention is a positive electrode terminal (2b) and the negative electrode terminal (2c) which protrude in the same direction from each of several semiconductor module (2), and predetermined | prescribed connection object component (4) are made into a positive electrode A terminal connection structure of a semiconductor module connected via a side bus bar (5) and a negative side bus bar (6), each of the positive side bus bar and the negative side bus bar extending flatly (5a, 6a) And a joint portion (5b, 6b) that is bent in the same direction from the plate portion and joined to the positive terminal or the negative terminal, each of the positive bus bar and the negative bus bar is The plate portion (5a) of one of the bus bars (as an example, the bus bar 5), the insulator (7), and the other bus bar (as an example) along the protruding direction of the positive electrode terminal and the negative electrode terminal from the plurality of semiconductor module sides. So that the plate portion (6a) of the bus bar 6) overlaps in this order, and the joint portion of the positive-side bus bar is joined to the positive terminal and the joint portion of the negative-side bus bar is joined to the negative terminal. The other bus bar is provided with a restraining portion (6d) that engages with the insulator so that the other bus bar does not displace to the side away from the insulator in the protruding direction.

  According to the said aspect, the other bus bar arrange | positioned on the opposite side to a semiconductor module with respect to an insulator is restrained on an insulator by a restraint part. Therefore, it is possible to prevent or suppress the displacement of the bus bar toward the side away from the insulator, that is, the floating of the bus bar with respect to the insulator. Therefore, the possibility of inconvenience such as a decrease in inductance reduction effect due to an increase in the distance between the plate portions of the pair of bus bars or a decrease in insulation due to a decrease in the contact area between the bus bars and the insulator is reduced or eliminated, A highly reliable terminal connection structure can be realized.

  In the above aspect, the plurality of semiconductor modules are provided side by side so as to form a row in a predetermined direction, and the positive electrode terminal and the negative electrode terminal are provided so as to protrude side by side with respect to the arrangement direction of the semiconductor modules, The plate portion of the one bus bar, the insulator, and the plate portion of the other bus bar may be overlapped along the protruding direction of the positive terminal and the negative terminal. Further, the connection target component is connected to each bus bar at one end of the positive bus bar and the negative bus bar, and the restraining portion is the other end located on the opposite side of the other bus bar to the connection target component. It may be provided so as to mesh with the insulator. Further, in the case where the other bus bar is formed by processing a metal plate, the restraining portion may be formed in a predetermined shape during the molding process of the bus bar. Alternatively, when the other bus bar is attached to the insulator, the restraining portion may be bent so as to engage with the insulator.

DESCRIPTION OF SYMBOLS 1 Power converter 2 Semiconductor module 2b Positive electrode terminal 2c Negative electrode terminal 3 Cooler 4 Capacitor (part to be connected)
5 Positive bus bar (one bus bar)
6 Negative bus bar (the other bus bar)
5a, 6a Plate part 5b, 6b Joint part 6d Claw part (restraint part)
7 Insulator

Claims (1)

A semiconductor module terminal connection structure for connecting a positive electrode terminal and a negative electrode terminal protruding in the same direction from each of a plurality of semiconductor modules and a predetermined connection target component via a positive electrode side bus bar and a negative electrode side bus bar,
Each of the positive electrode side bus bar and the negative electrode side bus bar is provided with a flat plate portion and a bonding portion bent in the same direction from the plate portion and joined to the positive electrode side terminal or the negative electrode side terminal,
Each of the positive-side bus bar and the negative-side bus bar includes a plate part of one of the bus bars, an insulator, and a plate of the other bus bar along the protruding direction of the positive and negative terminals from the plurality of semiconductor module sides. Arranged in such a manner that the joints of the positive-side bus bars are joined to the positive terminals and the joints of the negative-side bus bars are joined to the negative terminals,
A terminal connection structure for a semiconductor module, wherein the other bus bar is provided with a restraining portion that engages with the insulator so that the other bus bar is not displaced toward the side away from the insulator in the protruding direction.

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