JP2014057400A - Electric power conversion apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric power conversion apparatus which improves the cooling efficiency of capacitor elements and can connects a number of the capacitor elements with bus bars.SOLUTION: An electric power conversion apparatus 1 includes: a semiconductor module 2 incorporating a semiconductor element; multiple capacitor elements 3; and a cooler 4. The semiconductor module 2 and the multiple capacitor elements 3 are placed on a cooling surface 42 of the cooler 4. The two capacitor elements 3 make a pair and the pairs are placed on the cooling surface 42. Electrode terminals 31 (31a, 31b) of each capacitor element 3 protrude toward the counterpart capacitor element 3. Bus bars 5 (5a, 5b) are connected with the electrode terminals 31. The bus bars 5 are disposed between a pair of electrode body parts 30 when viewed in a protruding direction (X direction) of the electrode terminal 31.

Description

  The present invention relates to a power conversion device including a semiconductor module, a capacitor element, and a cooler for cooling them.

  For example, as a power conversion device that converts power between DC power and AC power, a semiconductor module incorporating a semiconductor element, a cooler that cools the semiconductor module, and a plurality of DC voltages applied to the semiconductor module are smoothed The capacitor element is known (see Patent Document 1 below).

  A refrigerant flow path is formed inside the cooler. By mounting the semiconductor module on the cooling surface of the cooler, the semiconductor module is cooled.

  The semiconductor module and the capacitor element are electrically connected by a bus bar. In the power converter, a bus bar is interposed between the capacitor element and the cooling surface. As a result, the capacitor element and the bus bar overlap each other when viewed from the normal direction of the cooling surface, and the power converter is downsized.

JP 2003-259656 A

  However, when the power converter is used, there is a problem that the capacitor element generates heat in addition to the semiconductor module. In the power converter, since the bus bar is interposed between the capacitor element and the cooling surface, the distance from the capacitor element to the cooling surface is long, and it is difficult to efficiently cool the capacitor element.

  Further, the power conversion device has a problem that the number of capacitor elements that can be connected to the bus bar is small because the capacitor elements are arranged only on one side of the bus bar in the normal direction of the cooling surface.

  The present invention has been made in view of such a background, and an object of the present invention is to provide a power converter that can increase the cooling efficiency of a capacitor element and can connect many capacitor elements to a bus bar.

One embodiment of the present invention is a semiconductor module including a semiconductor element;
A plurality of capacitor elements for smoothing a DC voltage applied to the semiconductor module;
A cooler for cooling the semiconductor module and the capacitor element;
The semiconductor module and the plurality of capacitor elements are mounted on the cooling surface of the cooler,
The capacitor element has an element body, and a positive terminal and a negative terminal protruding from the element body,
The positive terminal and the semiconductor module are electrically connected by a positive bus bar, the negative terminal and the semiconductor module are electrically connected by a negative bus bar,
A pair of the two capacitor elements are placed on the cooling surface, and the positive electrode terminal and the negative electrode terminal of one of the capacitor elements are directed to the other capacitor element. Projecting, the positive terminal and the negative terminal of the other capacitor element projecting toward the one capacitor element,
The positive electrode bus bar and the negative electrode bus bar are arranged between the pair of element main body portions in the protruding direction of the positive electrode terminal and the negative electrode terminal (Claim 1).

In the above power converter, two capacitor elements are arranged in pairs, and the electrode terminals (positive electrode terminal and negative electrode terminal) of each capacitor element protrude toward the other capacitor element. is there. A bus bar (a positive bus bar and a negative bus bar) is provided between the element main body portions of the pair of capacitor elements. That is, capacitor elements are provided on both sides of the bus bar in the protruding direction.
Therefore, the number of capacitor elements that can be connected to the bus bar can be increased. Moreover, since the bus bar is not interposed between the capacitor element and the cooling surface, the capacitor element can be brought close to the cooling surface. Therefore, the cooling efficiency of the capacitor element can be improved.

  As described above, according to the present invention, it is possible to provide a power conversion device that can increase the cooling efficiency of a capacitor element and can connect many capacitor elements to a bus bar.

1 is a partially transparent perspective view of a power conversion device in Embodiment 1. FIG. FIG. 3 is a partial perspective plan view of the power conversion device according to the first embodiment. The top view of the cooler in Example 1. FIG. IV-IV sectional drawing of FIG. VV sectional drawing of FIG. FIG. 3 is an enlarged perspective view of a capacitor element and a bus bar in the first embodiment. FIG. 3 is an enlarged plan view of a capacitor element and a bus bar in the first embodiment. FIG. 3 is an enlarged plan view of the capacitor element and the negative electrode bus bar in a state where the positive electrode bus bar is removed in Example 1. The circuit diagram of the power converter device in Example 1. FIG. The partial perspective top view of the power converter device in Example 2. FIG. The top view of the cooler in Example 2. FIG. Sectional drawing of the power converter device in Example 3. FIG. Sectional drawing of the power converter device in Example 4. FIG.

  The power conversion device can be a vehicle-mounted power conversion device mounted on a vehicle such as a hybrid vehicle or an electric vehicle.

In the power converter, it is preferable that a plurality of pairs of the capacitor elements are arranged in an arrangement direction orthogonal to both the normal direction of the cooling surface and the protruding direction.
In this case, more capacitor elements can be connected to the bus bar while being arranged near the cooling surface.

Further, the cooler has a metal base plate and a coolant channel formed inside the base plate, and when viewed from the normal direction of the cooling surface, the semiconductor module and the plurality of capacitors It is preferable that the element is configured to overlap the refrigerant flow path.
In this case, the distance from the semiconductor module to the coolant channel and the distance from the capacitor element to the coolant channel can be shortened. Therefore, the cooling efficiency of these semiconductor modules and capacitor elements can be further increased.

The positive electrode bus bar, the negative electrode bus bar, and the plurality of capacitor elements are preferably sealed to form a single component.
In this case, the positive electrode bus bar, the negative electrode bus bar, and the plurality of capacitor elements can be attached to the cooler at a time when the power conversion device is manufactured. Therefore, it is not necessary to separately attach these components to the cooler, and the manufacturing process of the power conversion device can be simplified.

Example 1
The Example which concerns on the said power converter device is described using FIGS. As shown in FIGS. 1 and 2, the power conversion device 1 of this example includes a semiconductor module 2 incorporating a semiconductor element, a plurality of capacitor elements 3 for smoothing a DC voltage applied to the semiconductor module 2, the semiconductor module 2, and And a cooler 4 for cooling the capacitor element 3.
The semiconductor module 2 and the plurality of capacitor elements 3 are mounted on the cooling surface 42 of the cooler 4.

The capacitor element 3 includes an element body 30 and a positive terminal 31 a and a negative terminal 31 b protruding from the element body 30. The element body 30 is formed in a column shape. The positive electrode terminal 31 a and the negative electrode terminal 31 b protrude from one end surface 301 of the both end surfaces 301 and 302 of the element main body 30.
The positive terminal 31a and the semiconductor module 2 are electrically connected by a positive bus bar 5a. The negative electrode terminal 31b and the semiconductor module 2 are electrically connected by the negative electrode bus bar 5b.

In this example, two capacitor elements 3 are paired and placed on the cooling surface 42. As shown in FIG. 4, the positive electrode terminal 31a and the negative electrode terminal 31b of one capacitor element 3a out of the pair of capacitor elements 3 (3a, 3b) protrude toward the other capacitor element 3b, and the positive electrode of the other capacitor element 3b. The terminal 31a and the negative electrode terminal 31b protrude toward the one capacitor element 3a.
As shown in FIGS. 4 and 7, the positive electrode bus bar 5a and the negative electrode bus bar 5b are arranged between the pair of element main bodies 30 (30a, 30b) in the protruding direction (X direction) of the positive electrode terminal 31a and the negative electrode terminal 31b. ing.

  As shown in FIGS. 1 and 2, the cooler 4 includes a metal base plate 40 and a refrigerant flow path 41 provided inside the base plate 40. The main surface of the base plate 40 is the cooling surface 40. In this example, four pairs of capacitor elements 3 are arranged in the arrangement direction (Y direction) orthogonal to both the normal direction (Z direction) of the cooling surface 42 and the X direction. The plurality of capacitor elements 3, the positive bus bar 5a, and the negative bus bar 5b are sealed with a sealing member to form one component (capacitor module 6).

  The bus bar 5 has an elongated shape in the Y direction. A positive input terminal 61 is formed at one end of the positive bus bar 5a in the Y direction. A negative input terminal 62 is formed at one end of the negative electrode bus bar 5b in the Y direction. These input terminals 61 and 62 are connected to a DC power source 70 (see FIG. 9). The semiconductor module 2 is provided on the side of the bus bar 5 opposite to the side where the input terminals 61 and 62 are provided in the Y direction.

  As shown in FIGS. 1 and 2, the semiconductor module 2 includes a sealing portion 26 that seals six semiconductor elements 24 (IGBT elements: see FIG. 9), a positive terminal 21 and a negative terminal 22, and an AC terminal 23. (23U, 23V, 23W) and a control terminal 25. The positive terminal 21 and the negative terminal 22 protrude from the sealing portion 26 toward the capacitor module 6 in the Y direction. The positive terminal 21 is connected to the positive bus bar 5a, and the negative terminal 22 is the negative bus bar 5b. The AC terminal 23 protrudes from the sealing portion 26 to the side opposite to the capacitor module 6 in the Y direction. The control terminal 25 protrudes from the main surface of the sealing portion 26 in the Z direction.

  The control circuit board 12 (see FIG. 4) is connected to the control terminal 25. By switching the semiconductor element 24 by the control circuit board 12, a DC voltage applied between the positive terminal 21 and the negative terminal 22 is converted into an AC voltage and output from the AC terminal 23. And it is comprised so that a three-phase alternating current motor (refer FIG. 9) may be driven using the obtained alternating voltage.

  As shown in FIGS. 4 and 5, a rib 400 protruding in the Z direction is formed on the periphery of the base plate 40. A flange 130 of the lid portion 13 is overlapped with the rib 400 and bolted.

  As shown in FIG. 5, through holes 131 and 132 are formed in the lid portion 13. The input connector 14 is fitted into one through hole 131, and the output connector 15 is fitted into the other through hole 132. The input connector 14 is connected to the positive input terminal 61 and the negative input terminal 62 of the capacitor module 6. The output connector 15 is connected to the AC terminal 23 of the semiconductor module 2.

  As shown in FIG. 3, a U-shaped cooling pipe 411 is embedded in the base plate 40. The inside of the cooling pipe 411 is the refrigerant flow path 41. The cooling pipe 411 has an inlet 412 for introducing the refrigerant 11 and an outlet 413 for extracting the refrigerant 11. The inlet 412 and the outlet 413 protrude in the Y direction from the side surface 490 including the short side of the base plate 40 having a rectangular plate shape, and the tips thereof are bent in the X direction.

  The cooling pipe 411 is made of metal and is manufactured by a sand casting method or the like. The base plate 40 is made of aluminum. A part of the cooling pipe 411 is embedded in the base plate 40. A portion of the cooling pipe 411 embedded in the base plate 40 has a diameter larger than that of the introduction port 412 or the outlet port 413.

  As described above, the cooling pipe 411 is formed in a U shape. That is, the refrigerant flow path 41 formed inside the cooling pipe 411 is U-shaped. As shown in FIGS. 2 and 3, the coolant channel 41 includes a first channel portion 41a that cools one capacitor element 3a of the pair of capacitor elements 3a and 3b, and a second channel element that cools the other capacitor element 3b. 3 flow path parts 41c, and the 2nd flow path part 41b which connects these 1st flow path parts 41a and the 3rd flow path parts 41c, and cools the semiconductor module 2. When viewed from the Z direction, the first flow path portion 41a overlaps with one capacitor element 3a, and the third flow path portion 41c overlaps with the other capacitor element 3b. The second flow path portion 41 b overlaps with the semiconductor module 2.

  On the other hand, as shown in FIG. 6, the positive electrode bus bar 5 a includes a bus bar main body portion 50 and connection portions 55 (55 a and 55 b) formed in the bus bar main body portion 50. The connection part 55 is formed in a pair. Of the pair of connection portions 55, one connection portion 55a is connected to the positive electrode terminal 31a of one capacitor element 3a, and the other connection portion 55b is connected to the positive electrode terminal 31a of the other capacitor element 3b. The negative electrode bus bar 5b has the same structure as the positive electrode bus bar 5a, and includes a bus bar main body 51 and connection portions 56 (56a, 56b) formed in the bus bar main body 51. Similarly to the connection part 55 of the positive electrode bus bar 5a, the connection part 56 of the negative electrode bus bar 5b is also formed in a pair. Of the pair of connection portions 56, one connection portion 56a is connected to the negative electrode terminal 31b of one capacitor element 3a, and the other connection portion 56b is connected to the negative electrode terminal 31b of the other capacitor element 3b.

  The bus bar main body portion 50 of the positive electrode bus bar 5a and the bus bar main body portion 51 of the negative electrode bus bar 5b are parallel to each other, and are arranged so that their main surfaces are orthogonal to the Z direction. As shown in FIGS. 6 and 7, the connecting portion 55 of the positive bus bar 5 a includes a first portion 52 protruding in the X direction from the bus bar main body portion 50, and the semiconductor portion 2 side in the Y direction from the first portion 52. The second portion 53 protrudes and the third portion 54 protrudes from the second portion 53 toward the cooling surface 42 in the Z direction. The positive electrode terminal 31a is brought into contact with the main surface of the third portion 54, and these are welded.

  As shown in FIGS. 6 and 8, the connecting portion 56 of the negative electrode bus bar 5b has the same structure as the connecting portion 55 of the positive electrode bus bar 5a. That is, the connecting portion 56 includes a first portion 57 protruding in the X direction from the bus bar main body portion 51, a second portion 58 protruding from the first portion 57 to the opposite side of the semiconductor module 2 in the Y direction, The third portion 59 protrudes from the two portions 58 toward the cooling surface 42 in the Z direction. As shown in FIG. 7, when viewed from the Z direction, the first portion 52 of the connecting portion 55 of the positive electrode bus bar 5a and the first portion 57 of the connecting portion 56 of the negative electrode bus bar 5b overlap each other.

  As shown in FIG. 6, in this example, the element main body 30 of the capacitor element 3 is formed in a cylindrical shape. The capacitor element 3 is an electrolytic capacitor. All the element main bodies 30 are arranged in parallel (see FIGS. 1 and 2). Further, as shown in FIG. 6, the distance from the positive electrode terminal 31a to the cooling surface 42 and the distance from the negative electrode terminal 31b to the cooling surface 42 are substantially equal.

  As shown in FIG. 7, a positive terminal connection portion 511 protruding in the X direction is formed at the end of the positive electrode bus bar 5a on the semiconductor module 2 side in the Y direction. The positive terminal connection portion 511 is overlapped with the positive terminal 21 of the semiconductor module 2 and is bolted. Further, as shown in FIG. 8, the negative electrode bus bar 5b has the same structure. That is, the negative terminal connecting portion 512 is formed at the end of the negative electrode bus bar 5b on the semiconductor module 2 side in the Y direction. The negative terminal connection part 512 protrudes on the opposite side to the protrusion side of the positive terminal connection part 511 in the X direction.

The effect of this example will be described. As shown in FIGS. 1 and 2, in this example, two capacitor elements 3 are arranged in pairs, and the electrode terminals 31 (the positive terminal 31a and the negative terminal 31b) of each capacitor element 3 are connected to the other side. It protrudes toward the capacitor element 3. The bus bar 5 (the positive bus bar 5a and the negative bus bar 5b) is provided between the element body portions 30 of the pair of capacitor elements 3. That is, the capacitor elements 3 (3a, 3b) are provided on both sides of the bus bar 5 in the X direction.
Therefore, the number of capacitor elements 3 that can be connected to the bus bar 5 can be increased. Further, since the bus bar 5 is not interposed between the capacitor element 3 and the cooling surface 42, the capacitor element 3 can be brought close to the cooling surface 42. Therefore, the cooling efficiency of the capacitor element 3 can be improved.

  Further, with the above configuration, the capacitor element 3 can be directly placed on the cooler 4, so that it is not necessary to provide a dedicated substrate or the like for mounting the capacitor element 3. Therefore, the number of parts can be reduced, and the manufacturing cost of the power conversion device 1 can be reduced.

In this example, as shown in FIGS. 1 and 2, a plurality of pairs of capacitor elements 3 are arranged in a direction (Y direction) orthogonal to both the Z direction and the X direction.
Therefore, more capacitor elements 3 can be connected to the bus bar 5 while being arranged at positions close to the cooling surface 42.

Further, in this example, as shown in FIG. 2, the semiconductor module 2 and the plurality of capacitor elements 3 are configured to overlap the refrigerant flow path 41 when viewed from the Z direction.
Therefore, the distance from the semiconductor module 2 to the refrigerant flow path 41 and the distance from the capacitor element 3 to the refrigerant flow path 41 can be shortened. Therefore, the cooling efficiency of the semiconductor module 2 and the capacitor element 3 can be further increased.

In this example, as shown in FIGS. 1 and 2, the positive electrode bus bar 5a, the negative electrode bus bar 5b, and the plurality of capacitor elements 3 are sealed to form one component (capacitor module 6).
Therefore, at the time of manufacturing the power conversion device 1, the positive electrode bus bar 5 a, the negative electrode bus bar 5 b, and the plurality of capacitor elements 3 can be attached to the cooler 4 at a time. Therefore, it is not necessary to separately attach these components to the cooler 4, and the manufacturing process of the power conversion device 1 can be simplified.

  Further, in this example, as shown in FIG. 6, the bus bar main body portion 50 of the positive electrode bus bar 5 a and the bus bar main body portion 51 of the negative electrode bus bar 5 b are arranged in parallel to the cooling surface 42. Therefore, the area facing the cooling surface 42 of the bus bar main body portions 50 and 51 can be increased. Therefore, the cooling efficiency of the bus bar main body portions 50 and 51 can be increased.

  As described above, according to the present invention, it is possible to provide a power conversion device that can increase the cooling efficiency of a capacitor element and can connect many capacitor elements to a bus bar.

  In this example, as shown in FIGS. 1 and 2, the positive electrode bus bar 5a, the negative electrode bus bar 5b, and the plurality of capacitor elements 3 are sealed and formed into one component, but these are not integrated into one component. These may be fixed separately to the cooler 4. For example, a claw-like fixing portion may be provided on the cooling surface 42, and the individual capacitor elements 3 may be fixed using the fixing portion.

(Example 2)
In this example, the direction of the refrigerant flow path 41 is changed. In this example, as shown in FIGS. 10 and 11, a U-shaped cooling pipe 411 is embedded in the base plate 40 as in the first embodiment, and the inside of the cooling pipe 411 serves as a refrigerant flow path 41. Yes. The refrigerant flow path 41 includes a first flow path section 41a that cools the semiconductor module 2, a third flow path section 41c that cools the capacitor element 3, and the first flow path section 41a and the third flow path section 41c. It consists of the 2nd flow path part 41b to connect.

  Similarly to the first embodiment, the cooling pipe 411 includes an inlet 412 for introducing the refrigerant 11 and an outlet 413 for extracting the refrigerant 11. The inlet 412 and the outlet 413 protrude in the X direction from the side surface 491 including the long side of the base plate 40 having a rectangular plate shape, and the tips thereof are bent in the Y direction.

  Others are the same as in the first embodiment. Moreover, among the symbols used in the drawings relating to this example, the same symbols as those used in the first embodiment represent the same components as in the first embodiment unless otherwise indicated.

(Example 3)
In this example, the structure of the capacitor module 6 is changed. As shown in FIG. 12, in this example, no sealing member is interposed between the element main body 30 of the capacitor element 3 and the cooling surface 42, and the element main body 30 is in direct contact with the cooling surface 42. Yes. Therefore, the cooling efficiency of the element body 30 can be further increased.

  Others are the same as in the first embodiment. Moreover, among the symbols used in the drawings relating to this example, the same symbols as those used in the first embodiment represent the same components as in the first embodiment unless otherwise indicated.

Example 4
In this example, the direction of the bus bar 5 with respect to the cooling surface 42 is changed. As shown in FIG. 13, in this example, the bus bar main body portion 50 of the positive electrode bus bar 5a and the bus bar main body portion 51 of the negative electrode bus bar 5b are arranged so as to be orthogonal to the cooling surface 42, respectively. These two bus bar main body portions 50 and 51 are parallel to each other. As in the first embodiment, the positive bus bar 5 a is connected to the positive terminal 31 a of the capacitor element 3, and the negative bus bar 5 b is connected to the negative terminal 31 b of the capacitor element 3.

  If it does in this way, the space | interval in the X direction of the two element main-body parts 30a and 30b can be narrowed. Therefore, the power converter 1 can be reduced in size.

  Others are the same as in the first embodiment. Moreover, among the symbols used in the drawings relating to this example, the same symbols as those used in the first embodiment represent the same components as in the first embodiment unless otherwise indicated.

DESCRIPTION OF SYMBOLS 1 Power converter 2 Semiconductor module 3 Capacitor element 30 Element main-body part 31a Positive electrode terminal 31b Negative electrode terminal 4 Cooler 42 Cooling surface 5a Positive electrode bus bar 5b Negative electrode bus bar

Claims (4)

A semiconductor module (2) containing a semiconductor element (24);
A plurality of capacitor elements (3, 3a, 3b) for smoothing a DC voltage applied to the semiconductor module (2);
A cooler (4) for cooling the semiconductor module (2) and the capacitor element (3);
The semiconductor module (2) and the plurality of capacitor elements (3) are placed on the cooling surface (42) of the cooler (4),
The capacitor element (3) has an element body (30), a positive terminal (31a) and a negative terminal (31b) protruding from the element body (30),
The positive terminal (31a) and the semiconductor module (2) are electrically connected by a positive bus bar (5a), and the negative terminal (31b) and the semiconductor module (2) are electrically connected by a negative bus bar (5b). Connected to
A pair of the two capacitor elements (3a, 3b) is placed on the cooling surface (42), and one of the capacitor elements (3a) out of the pair of capacitor elements (3a, 3b). The positive terminal (31a) and the negative terminal (31b) protrude toward the other capacitor element (3b), and the positive terminal (31a) and the negative terminal (31b) of the other capacitor element (3b) , Projecting toward the one capacitor element (3a),
The positive electrode bus bar (5a) and the negative electrode bus bar (5b) are arranged between the pair of element main body portions (30) in the protruding direction of the positive electrode terminal (31a) and the negative electrode terminal (31b). The power converter device (1) characterized by these.   The power conversion device (1) according to claim 1, wherein a plurality of pairs of the capacitor elements (3) are arranged in an arrangement direction orthogonal to both the normal direction of the cooling surface (42) and the protruding direction. The power converter device (1) characterized by the above-mentioned.   The power converter (1) according to claim 1 or 2, wherein the cooler (4) includes a metal base plate (40) and a refrigerant flow path (41) provided inside the base plate (40). ) And the semiconductor module (2) and the plurality of capacitor elements (3) overlap the refrigerant flow path (41) when viewed from the normal direction of the cooling surface (42). The power converter device (1) characterized by being comprised.   In the power converter device (1) according to any one of claims 1 to 3, the positive electrode bus bar (5a), the negative electrode bus bar (5b), and the plurality of capacitor elements (3) are sealed, A power converter (1) characterized in that it is a single component.

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