JP2016149912A - Electric power conversion system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric power conversion system which enables further improvement of the cooling efficiency of a capacitor element.SOLUTION: A capacitor 2 includes: a capacitor element 21; an electrode part 22; and a bus bar 23. The capacitor element 21 has: a dielectric substance 210; and a metal layer 211 formed on a surface of the dielectric substance 210. The electrode part 22 is formed on the capacitor element 21 and connected to the metal layer 211. The bus bar 23 includes a bottom part 25 and a protruding part 26. The bottom part 25 is connected to a major surface S1 of the electrode part 22 which is opposite to a side connected to the metal layer 211. The protruding part 26 is erected from the bottom part 25 in a thickness direction of the bottom part 25. The electrode part 22 is fitted in a recessed part 239 formed by the bottom part 25 and the protruding part 26. A part of the bus bar 23 is disposed between the electrode part 22 and the heat radiation member 3.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power conversion device including a capacitor and a heat dissipation member that cools the capacitor.

  2. Description of the Related Art Conventionally, as a power conversion device that performs power conversion between DC power and AC power, a device including a capacitor to which a DC voltage is applied and a heat dissipation member that cools the capacitor is known (see Patent Document 1 below). ). The capacitor includes a capacitor element, an electrode portion formed on the capacitor element, and a bus bar connected to the electrode portion. The bus bar is used to electrically connect the capacitor element to other electronic components.

  The capacitor element includes a dielectric and a metal layer formed on the surface of the dielectric. When the power conversion device is operated, a ripple current flows through the metal layer to generate resistance heat, and the temperature of the capacitor element rises. Therefore, the power converter is configured to cool the capacitor element using the heat dissipation member.

JP 2014-161159 A

  However, the power conversion device has room for improvement in the cooling efficiency of the capacitor element. That is, as described above, the capacitor element includes a dielectric and a metal layer, and this metal layer mainly generates heat. The power converter has a structure in which a capacitor element is directly cooled from the outside using a heat radiating member. Therefore, there is a problem that heat generated from the metal layer is shielded by the dielectric and heat is not easily transmitted to the heat radiating member. Therefore, the cooling efficiency of the capacitor element cannot be sufficiently increased.

  The present invention has been made in view of such a background, and an object of the present invention is to provide a power conversion device that can further increase the cooling efficiency of a capacitor element.

One aspect of the present invention is a power converter including a capacitor and a heat dissipation member that cools the capacitor,
The capacitor is
A capacitor element having a dielectric and a metal layer formed on the surface of the dielectric;
An electrode portion formed on the capacitor element and connected to the metal layer;
A bus bar connected to the electrode part,
The bus bar includes a bottom portion connected to a main surface of the electrode portion opposite to a side connected to the metal layer, and a protrusion erected in the thickness direction of the bottom portion from the bottom portion. And the electrode part is fitted in a concave part formed by the protrusion and
A part of the bus bar is interposed between the electrode part and the heat dissipation member.

In the power converter, a part of the bus bar is interposed between the electrode portion and the heat dissipation member.
Therefore, the cooling efficiency of the capacitor element can be increased. That is, with the above configuration, a part of the bus bar is disposed in the vicinity of the heat radiating member, so that this part can be cooled by the heat radiating member, and further, the electrode portion connected to the bus bar can be cooled. As described above, the capacitor element includes a dielectric and a metal layer formed on the surface of the dielectric, and the metal layer mainly generates heat. The metal layer is connected to the electrode part. Therefore, by cooling the bus bar and the electrode part with the heat radiating member, it is possible to transmit the heat generated from the metal layer to the electrode part and further to the heat radiating member via the bus bar. Therefore, the dielectric is less likely to hinder heat conduction, and the cooling efficiency of the capacitor element can be increased.

The bus bar includes the bottom and the protrusion. The electrode portion is fitted in the concave portion formed by the bottom portion and the protrusion.
Therefore, the cooling efficiency of the capacitor element can be further increased. That is, when the electrode portion is fitted in the concave portion, the electrode portion can be cooled from the main surface by the bottom portion, and the electrode portion can be cooled from the side surface by the protrusion. Therefore, it becomes easier to lower the temperature of the electrode part, and the capacitor element can be cooled more effectively.

  As described above, according to the present invention, it is possible to provide a power conversion device that can further increase the cooling efficiency of a capacitor element.

FIG. 4 is a cross-sectional view of the capacitor and the heat radiating member in the first embodiment, taken along the line II in FIG. II-II sectional drawing of FIG. FIG. 3 is a view taken in the direction of arrow III in FIG. FIG. 3 is a perspective view of a capacitor in the first embodiment. The perspective view of the bus-bar and connection terminal in Example 1. FIG. FIG. 8 is a cross-sectional view of the power conversion device according to the first embodiment, and is a cross-sectional view taken along VI-VI in FIG. 7. VII-VII sectional drawing of FIG. FIG. 3 is an enlarged cross-sectional view of a main part of the capacitor in Example 1. The circuit diagram of the power converter device in Example 1. FIG. Sectional drawing of the capacitor | condenser and heat radiating member in Example 2. FIG. Sectional drawing of the capacitor | condenser and heat radiating member in Example 3. FIG. Sectional drawing of the capacitor | condenser and heat radiating member in Example 4. FIG. Sectional drawing of the capacitor | condenser and heat radiating member in Example 5. FIG. The perspective view of the bus-bar and connection terminal in Example 5. FIG. Sectional drawing of the bus-bar and heat radiating member in Example 6. FIG. The perspective view of the insulating member in Example 6. FIG. The perspective view of the insulating member in which the side wall was formed in cyclic | annular form in Example 6. FIG. Sectional drawing of the capacitor | condenser and heat radiating member in Example 7. FIG. Sectional drawing of the capacitor | condenser and heat dissipation member in a comparative example.

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

Example 1
The Example which concerns on the said power converter device is described using FIGS. As shown in FIG. 6, the power conversion device 1 of this example includes a capacitor 2 and a heat radiating member 3 that cools the capacitor 2. As shown in FIGS. 1 to 3, the capacitor 2 includes a capacitor element 21, an electrode portion 22, and a bus bar 23.

  As shown in FIG. 8, the capacitor element 21 includes a dielectric 210 and a metal layer 211 formed on the surface of the dielectric 210. The electrode portion 22 is formed on the capacitor element 21 and is connected to the metal layer 211. Further, as shown in FIGS. 1 and 2, the bus bar 23 is connected to the electrode portion 22.

The bus bar 23 includes a bottom 25 and a protrusion 26. The bottom portion 25 is connected to the main surface S <b> 1 on the opposite side of the electrode portion 22 from the side connected to the metal layer 211. The protrusion 26 is erected from the bottom 25 in the thickness direction (X direction) of the bottom 25. The electrode portion 22 is fitted in the concave portion 239 formed by the bottom portion 25 and the protrusion 26.
A part of the bus bar 23 is interposed between the electrode portion 22 and the heat dissipation member 3.

  The power conversion device 1 of this example is a vehicle-mounted power conversion device to be mounted on a vehicle such as an electric vehicle or a hybrid vehicle. The capacitor element 21 is a film capacitor element. As shown in FIG. 8, the capacitor element 21 includes a film (dielectric 210) made of a synthetic resin and a metal layer 211 formed on the surface of the film. The capacitor element 21 is formed by winding this film. The metal layer 211 includes a first metal layer 211a connected to one electrode portion 22a and a second metal layer 211b connected to the other electrode portion 22b (see FIG. 1). The electrode portion 22 is made of a porous metal material such as a metallicon electrode.

  As shown in FIGS. 6 and 9, the power conversion device 1 of this example includes two capacitors 2 (2a and 2b), which are a filter capacitor 2a and a smoothing capacitor 2b.

  As shown in FIGS. 1 and 4, a connection terminal 230 for electrically connecting the capacitor element 21 to another electronic component 5 extends from the bus bar 23. The bus bar 23 and the connection terminal 230 are made of a copper plate or the like.

As shown in FIG. 1, the capacitor 2 includes a moisture-resistant member 24 that covers the capacitor element 21. The moisture resistant member is made of a synthetic resin such as an epoxy resin. The moisture-resistant member 24 covers the protrusion 26 of the bus bar 23. Further, the bus bar 23 covers the main surface S <b> 1 of the electrode part 22. The bus bar 23 is made of a metal material having moisture resistance.
In the present specification, “having moisture resistance” means having a property of not transmitting moisture.

  As shown in FIG. 5, in this example, the protrusion 26 of the bus bar 23 is formed in an annular shape. As shown in FIG. 4, the entire circumference of the annular protrusion 26 is covered with a moisture-resistant member 24.

  As described above, since the electrode portion 22 is formed of a porous metal material, moisture passes therethrough. Further, when moisture enters the capacitor element 21, the metal layer 211 (see FIG. 8) of the capacitor element 21 may be oxidized, and the capacitance may be reduced. Therefore, in this example, the electrode part 22 and the capacitor element 21 are sealed with a moisture-resistant bus bar 23 and a moisture-resistant member 24. This prevents moisture from entering the electrode portion 22 and the capacitor element 21 from the outside.

  Moreover, in this example, the bus bar 23 is cooled using the heat radiating member 3. Thereby, the electrode part 22 is cooled and the capacitor | condenser element 21 is further cooled. Therefore, the bus bar 23 also has a function as a cooling plate. Thus, the bus bar 23 of this example functions as a cooling plate for cooling the capacitor element 21, functions as a waterproof plate for preventing moisture from entering from the outside, and the capacitor element 21 and other electronic devices. It also has a function for electrically connecting the component 5.

  As shown in FIGS. 1 and 2, bus bars 23 (23a, 23) are connected to the two electrode portions 22 (22a, 22b) formed in the capacitor element 21, respectively. A part of each of the two bus bars 23 (23a, 23b) is interposed between the electrode portion 22 (22a, 22b) and the heat dissipation member 3.

  In the present example, the bottom portion 25 of the bus bar 23 is interposed between the electrode portion 22 and the heat dissipation member 3.

  As shown in FIGS. 1 and 2, in this example, a part of the capacitor element 21 is fitted in the concave portion 239. Further, the side surface S <b> 3 of the capacitor element 21 is in contact with the protrusion 26.

  On the other hand, the heat radiating member 3 of this example is a cooling pipe 3a in which a flow path 12 through which the refrigerant 11 flows is formed. The cooling pipe 3a is made of metal. An insulating member 6 is interposed between the cooling pipe 3a and the bus bar 23 to insulate them. The insulating member 6 is made of ceramic.

As shown in FIG. 6, the power conversion device 1 of this example includes a plurality of electronic components 5 (5 _S , 5 _L ) other than the capacitor 2. The electronic component 5, there is a semiconductor module _{5 S} and the reactor _{5 L.} Capacitor 2 (2a, 2b) and the reactor _{5 L} and the semiconductor module _{5 S} is electrically connected by a connecting plate 14. Thus, the booster circuit 100 (see FIG. 8) and the inverter circuit 101 are configured.

In this example, the electronic component 5 (5 _S , 5 _L ), the capacitor 2 (2a, 2b), and the cooling pipe 3a are stacked in the X direction to form the stacked body 10. The laminate 10 is stored in a case 13. A pressure member 4 (plate spring) is disposed between the first wall 131 of the case 13 and the laminated body 10. The pressurizing member 4 presses the laminated body 10 toward the second wall portion 132 of the case 13. Thus, the bus bar 23 of the capacitor 2 (2a, 2b) is pressed against the cooling pipe 3a to cool the bus bar 23. Further, the contact pressure between the electronic component 5 (5 _S , 5 _L ) and the cooling pipe 3 a is secured by the pressing force of the pressurizing member 4, and the laminated body 10 is fixed in the case 10.

As shown in FIG. 5, the two cooling pipes 3 a adjacent to each other in the X direction are connected by a pair of connecting pipes 17. The connecting pipes 17 are respectively provided at both ends of the cooling pipe 3a in the width direction (Y direction) orthogonal to both the protruding direction (Z direction) of the power terminal 52 (see FIG. 6) and the X direction. In addition, an inlet pipe 15 for introducing the refrigerant 11 and an outlet pipe 16 for leading the refrigerant 11 are connected to some of the cooling pipes 3a. When the refrigerant 11 is introduced from the introduction pipe 15, the refrigerant 11 flows through all the cooling pipes 3 a through the connecting pipe 17 and is led out from the outlet pipe 16. Thus, the capacitor 2 (2a, 2b) and the electronic component 5 (5 _S , 5 _L ) are cooled.

As shown in FIG. 7, the semiconductor module 5 </ b> _S includes a main body 51 containing a semiconductor element 50 (see FIG. 9), a power terminal 52 protruding from the main body 51, and a control terminal 53. The power terminal 52 includes a positive terminal 52p and a negative terminal 52n to which a DC voltage is applied, and an AC terminal 52c connected to the three-phase AC motor 81 (see FIG. 9). The control terminal 53 is connected to the control circuit board 18. The switching operation of the semiconductor element 50 is controlled by the control circuit board 18.

As shown in FIG. 9, in this example, a filter capacitor 2a, a reactor 5 _L, and a part of the semiconductor module 5 _S, is formed with the step-up circuit 100. Further, the inverter circuit 101 is formed by the other semiconductor module _5S and the smoothing capacitor 2b. In this example, the booster circuit 100 is used to boost the voltage of the DC power supply 8, and then the inverter circuit 101 is used to convert DC power into AC power. The three-phase AC motor 81 is driven using the obtained AC power. As a result, the vehicle is running. The filter capacitor 2a removes noise current contained in the current I supplied from the DC power supply 8. Further, the smoothing capacitor 2b smoothes the DC voltage boosted by the booster circuit 100.

The effect of this example will be described. As shown in FIGS. 1 and 2, in this example, a part of the bus bar 23 is interposed between the electrode portion 22 and the heat dissipation member 3.
Therefore, the cooling efficiency of the capacitor element 21 can be increased. That is, in the above configuration, a part of the bus bar 23 is disposed in the vicinity of the heat radiating member 3, so that this part can be cooled by the heat radiating member 3, and further, the electrode portion 22 connected to the bus bar 23 can be cooled. . As described above, the capacitor element 22 includes the dielectric 210 (see FIG. 8) and the metal layer 211 formed on the surface of the dielectric 210, and the metal layer 211 mainly generates heat. The metal layer 211 is connected to the electrode part 22. Therefore, by cooling the bus bar 23 and the electrode part 22 with the heat radiating member 3, it is possible to transmit the heat generated from the metal layer 21 to the electrode part 22 and further to the heat radiating member 3 through the bus bar 23. Therefore, the dielectric 210 is less likely to hinder heat conduction, and the cooling efficiency of the capacitor element 21 can be increased.

Further, the bus bar 23 of this example includes the bottom portion 25 and the protrusion 26. The electrode portion 22 is fitted in the concave portion 239 formed by the bottom portion 25 and the protrusion 26.
Therefore, the cooling efficiency of the capacitor element 21 can be further increased. That is, when the electrode portion 22 is fitted into the concave portion 239, the electrode portion 22 can be cooled from the main surface S1 by the bottom portion 25, and the electrode portion 22 can be cooled from the side surface S4 by the protrusion 26. Therefore, it becomes easier to lower the temperature of the electrode part 22, and the capacitor element 21 can be cooled more effectively.

  In this example, the side surface S4 of the electrode portion 22 is in contact with the protrusion 26. Therefore, it is easy to transfer the heat of the electrode part 22 from the side surface S4 to the protrusion 26.

As shown in FIGS. 1 and 2, in this example, the bottom portion 25 of the bus bar 23 is interposed between the electrode portion 22 and the heat radiating member 3.
Therefore, the cooling efficiency of the capacitor element 21 can be further increased. That is, as shown in FIG. 10, the protrusion 26 of the bus bar 23 can be interposed between the electrode portion 22 and the heat dissipation member 3, but the area where the protrusion 26 is in contact with the electrode portion 22 is as follows. Therefore, even if the protrusion 26 is cooled, it is difficult to effectively cool the electrode portion 22. For this reason, the cooling efficiency of the capacitor element 21 may be reduced. On the other hand, as shown in FIGS. 1 and 2, if the bottom portion 25 is interposed between the electrode portion 22 and the heat dissipation portion 3, the bottom portion 25 having a large area in contact with the electrode portion 22 is cooled. Can do. Therefore, the electrode part 22 can be cooled efficiently and the cooling efficiency of the capacitor | condenser element 21 can be improved.

  In this example, as shown in FIGS. 1 and 2, a part of the capacitor element 21 is fitted in the concave portion 239. Therefore, not only the electrode portion 22 but also a part of the capacitor element 21 can be cooled from the side surface S3 by the protrusion 26. Therefore, the cooling efficiency of the capacitor element 21 can be further increased.

  Further, as shown in FIG. 5, in this example, the protrusion 26 is formed in an annular shape. Therefore, side surface S4 of electrode part 22 can be cooled over the entire circumference, and the cooling efficiency of capacitor element 21 can be further increased.

  As shown in FIGS. 1 and 2, in this example, the capacitor element 23 and the electrode portion 22 are sealed by a moisture-resistant member 24 and a bus bar 23 having moisture resistance. Therefore, moisture can be prevented from entering the electrode portion 22 and the capacitor element 23 from the outside, and fluctuations in the electrical characteristics of the capacitor element 23 can be suppressed.

  In this example, the protrusion 26 of the bus bar 23 is covered with the moisture-resistant member 24. Therefore, it is possible to more reliably suppress moisture from entering the capacitor element 23 from the outside.

  In addition, since the recessed part 239 is formed in the bus bar 23 of this example, the side surface S5 can be covered with the moisture-resistant member 24, reducing the weight of the bus bar 23. That is, in order to cover the side surface S5 of the bus bar 23 with the moisture-resistant member 24, it is necessary to ensure a certain length or more in the X direction of the side surface S5. Therefore, as shown in FIG. 19, if a concave portion is not formed on the bus bar 923, the entire bus bar 923 needs to be thickened to sufficiently secure the length L in the X direction of the bus bar 923. It becomes difficult to reduce the weight. Further, since the electrode portion 922 and the capacitor element 921 cannot be fitted into the concave portion, the entire length of the capacitor 92 in the X direction tends to be long. On the other hand, as shown in FIG. 1, if the concave portion 239 is formed as in this example, the length in the X direction of the side surface S5 of the bus bar 23 is set to a length that can be covered by the moisture-resistant member 24. The entire bus bar 23 can be reduced in weight. Moreover, since the electrode part 22 and the capacitor | condenser element 21 can be fitted to the recessed part 239, the X direction length of the whole capacitor | condenser 2 can be shortened.

In this example, bus bars 23 (23a, 23) are connected to the two electrode portions 22 (22a, 22b) formed in the capacitor element 21, respectively. A part of both of these two bus bars 23 (23a, 23b) is interposed between the electrode portion 22 (22a, 22b) and the heat dissipating member 3.
Therefore, both the two bus bars 23 (23a, 23b) can be cooled by the heat radiating member 3, and the capacitor element 21 can be cooled more efficiently.

  As described above, according to this example, it is possible to provide a power conversion device that can further increase the cooling efficiency of the capacitor element.

  In this example, the cooling pipe 3a is used as the heat radiating member 3, but the present invention is not limited to this. For example, a case 13 (see FIG. 6) or a heat sink (not shown) is used as the heat radiating member 3. Also good.

(Example 2)
In the following embodiments, the same reference numerals used in the drawings among the reference numerals used in the drawings represent the same components as in the first embodiment unless otherwise specified.

This example is an example in which the portion of the bus bar 23 that is cooled by the heat radiating member 3 is changed. As shown in FIG. 10, in this example, a protrusion 26 of the bus bar 23 is interposed between the electrode portion 22 and the heat dissipation member 3. Accordingly, the protrusion 26 is cooled by the heat radiating member 3.
In addition, the configuration and operational effects similar to those of the first embodiment are provided.

(Example 3)
In this example, the structure of the moisture-resistant member 24 is changed. As shown in FIG. 11, the moisture resistant member 24 of this example includes a film winding portion 241 formed by winding a moisture resistant film 240 having moisture resistance. As the moisture resistant film 240, for example, an aluminum laminated film in which aluminum is deposited on the surface of an insulating film can be used. The moisture-resistant film 240 covers the capacitor element 21 and also covers the tip portion 261 that is the portion of the protrusion 26 on the opening side of the concave portion 239 in the X direction. Further, the connection terminal 230 extends from a base end portion 262 that is a portion of the protrusion 26 on the bottom 25 side in the X direction.

The effect of this example will be described. At the time of manufacturing the capacitor 2, the moisture resistant film 240 can be wound while being pulled. Therefore, the moisture resistant film 240 is easily adhered to the capacitor element 21 and the protrusion 26. Therefore, it is difficult to form a gap between the moisture-resistant film 240 and the protrusion 26 and the like, and it is easy to improve the moisture resistance between them. Therefore, even if the number of turns of the moisture resistant film 240 is small, high moisture resistance can be ensured, and the thickness can be reduced as compared with the case where the moisture resistant member 24 is formed by molding a synthetic resin. Therefore, the capacitor 2 can be reduced in size.
In addition, since the aluminum laminate film has higher moisture resistance than the epoxy resin, the power conversion device 1 of this example can improve the moisture resistance of the moisture resistant member 24 as compared with the first embodiment.
In addition, the configuration and operational effects similar to those of the first embodiment are provided.

Example 4
In this example, the structure of the moisture-resistant member 24 is changed. As shown in FIG. 12, the moisture resistant member 24 of this example includes a film winding portion 241 formed by winding a moisture resistant film 240 and a resin molding portion 242 formed by molding a synthetic resin. The moisture resistant film 240 covers the capacitor element 21 and the tip portion 261 of the protrusion 26. The resin molding part 242 covers the film winding part 241. The resin molding part 242 also covers the base end part 262 of the protrusion.

  As the moisture resistant film 240, for example, an aluminum laminate film can be used as in the third embodiment. Further, for example, an epoxy resin can be used as the synthetic resin constituting the resin molding portion 242.

  The effect of this example will be described. Since the moisture-resistant member 24 of this example includes the film winding part 241 and the resin molding part 242, the capacitor element 21 and the bus bar 23 can be covered twice. Therefore, the moisture resistant member 24 can be made thinner than the case of using only the epoxy resin while ensuring high moisture resistance.

Further, as described in Example 3, since the moisture resistant film 240 has higher moisture resistance than the epoxy resin, it is easy to obtain a high moisture resistance effect even when the thin moisture resistant film 240 is used. Therefore, the film winding part 241 can easily reduce the thickness. Therefore, by forming the film winding part 241, the entire thickness of the moisture resistant member 24 can be reduced.
In addition, the configuration and operational effects similar to those of the first embodiment are provided.

(Example 5)
In this example, the shape of the bus bar 23 is changed. As shown in FIGS. 13 and 14, the protrusion 26 of this example includes an inner portion 263 and an outer portion 264. The inner portion 263 and the outer portion 264 are each formed in an annular shape. The inner portion 263 is connected to the bottom portion 25. Further, the outer portion 264 is disposed outside the inner portion 263. A concave portion 239 is formed by the inner portion 263 and the bottom wall 25.

  The inner portion 263 and the outer portion 264 are connected to each other at the end portion 28 on the opening side of the concave portion 239 in the X direction. Further, the connection terminal 230 extends from the end portion 29 on the bottom wall 25 side of the outer portion 264 in the X direction.

  In this example, the bus bar 23 and the connection terminal 230 are integrally formed by pressing one metal plate.

  In this example, the moisture resistant member 24 covers the distal end portion 261 of the outer portion 264 that is the portion on the opening side of the concave portion 239 in the X direction. The moisture resistant member 24 of this example is formed by winding a moisture resistant film 240 having moisture resistance, as in the third embodiment.

The effect of this example will be described. The protrusion 26 of the present example includes an inner portion 263 and an outer portion 264, which are connected to each other at the opening-side end portion 28 of the concave portion 239 in the X direction. Further, the connection terminal 230 extends from the end portion 29 on the bottom wall 25 side of the outer portion 264 in the X direction.
In this way, by processing a single metal plate, the bus bar 23 that can cover the tip 261 of the protrusion 26 with the moisture-resistant member 24 and the connection terminal 230 can be integrally formed. Therefore, the bus bar 23 and the connection terminal 230 can be easily manufactured, and the manufacturing cost of the capacitor 2 can be easily reduced.
In addition, the configuration and operational effects similar to those of the second embodiment are provided.

(Example 6)
In this example, the structure of the insulating member 6 is changed. As shown in FIGS. 15 and 16, the insulating member 6 of this example includes a bottom wall 61 that contacts the cooling pipe 3 a and a side wall 62 that protrudes from the bottom wall 61 in the X direction. The bottom wall 61 and the side wall 62 form a bus bar fitting recess 60 into which the bus bar 23 is fitted.

The effect of this example will be described. If it is set as the said structure, the creeping distance between the metal cooling pipes 3a and the bus-bar 23 can be lengthened. Therefore, it becomes easy to insulate the cooling pipe 3a and the bus bar.
In addition, the configuration and operational effects similar to those of the first embodiment are provided.

  In this example, as shown in FIG. 16, the side walls 62 are not formed at both end portions 611 and 612 of the bottom wall 61 in the Y direction. In this example, since the length of the bottom wall 61 in the Y direction is longer than the length of the bus bar 23 in the Y direction (see FIG. 4), even if the side walls 62 are not formed on the both ends 611, 612, The creepage distance between the bus bar 23 and the cooling pipe 3a in the Y direction can be increased. Therefore, the bus bar 23 and the cooling pipe 3a can be sufficiently insulated. When the length of the bottom wall 61 in the Y direction is short, as shown in FIG. 15, it is desirable to form the side walls 62 at the both end portions 611 and 612 of the bottom wall 61. In this way, the side wall 62 can surround the bus bar 23 from four directions, and therefore, it is difficult to form a portion where the creepage distance between the bus bar 23 and the cooling pipe 3a is locally shortened. Therefore, the bus bar 23 and the cooling pipe 3a can be sufficiently insulated.

(Example 7)
In this example, the structure of the capacitor 2 is changed. In this example, the moisture element 24 made of resin covers the capacitor element 21 and the bottom 25 and protrusion 26 of the bus bar 23. A part of the moisture-resistant member 24 is interposed between the bottom portion 25 and the heat radiating member 3. The heat dissipation member 3 is made of metal. Further, in this example, the insulating member 6 (see FIG. 1) is not interposed between the bus bar 23 and the heat radiating member 3. In this example, the moisture-resistant member 24 is used to ensure electrical insulation between the bus bar 23 and the heat dissipation member 3.

  The effect of this example will be described. With the above configuration, it is not necessary to provide the insulating member 6. Therefore, the number of parts can be reduced, and the manufacturing cost of the power conversion device 1 can be reduced. Moreover, since it is not necessary to interpose the insulating member 6 between the bus bar 23 and the heat radiating member 3, the manufacturing process of the power converter device 1 can be simplified.

DESCRIPTION OF SYMBOLS 1 Power converter 2 Capacitor 21 Capacitor element 210 Dielectric 211 Metal layer 22 Electrode part 23 Bus bar 25 Bottom part 26 Protrusion part

Claims (9)

A power converter (1) comprising a capacitor (2) and a heat dissipating member (3) for cooling the capacitor (2),
The capacitor (2)
A capacitor element (21) having a dielectric (210) and a metal layer (211) formed on the surface of the dielectric (210);
An electrode part (22) formed on the capacitor element (21) and connected to the metal layer (211);
A bus bar (23) connected to the electrode part (22),
The bus bar (23) includes a bottom portion (25) connected to a main surface (S1) opposite to the side connected to the metal layer (211) of the electrode portion (22), and the bottom portion (25). A protrusion (26) standing in the thickness direction of the bottom (25), and the electrode portion (22) on the concave portion (239) formed by the bottom (25) and the protrusion (26). ) Is fitted,
A part of the bus bar (23) is interposed between the electrode part (22) and the heat dissipation member (3). The power conversion device (1).   The power conversion device (1) according to claim 1, wherein the bottom portion (25) is interposed between the electrode portion (22) and the heat dissipation member (3).   The power conversion device (1) according to claim 1 or 2, wherein a part of the capacitor element (21) is fitted into the concave portion (239).   The power converter (1) according to any one of claims 1 to 3, wherein the protrusion (26) is formed in an annular shape.   The capacitor (2) includes a moisture resistant member (24) having moisture resistance, the bus bar (23) has moisture resistance, the electrode part (22) is formed of a porous metal material, and the moisture resistant member ( 24) and the bus bar (23), the capacitor element (23) and the electrode part (22) are sealed, and the protrusion (26) is covered by the moisture-resistant member (24). The power converter device (1) according to claim 4, characterized in that   The power converter (1) according to claim 5, wherein the moisture resistant member (24) includes a film winding part (241) formed by winding a moisture resistant film (240) having moisture resistance.   The said moisture-resistant member (24) is equipped with the resin molding part (242) formed by shape | molding a synthetic resin, and the said film winding part (241), The power converter device (6) of Claim 6 characterized by the above-mentioned. 1).   The heat radiating member (3) is made of metal, and an insulating member (6) for insulating them is interposed between the bus bar (23) and the heat radiating member (3), and the insulating member (6) The power converter (1) according to any one of claims 1 to 7, wherein a bus bar fitting recess (60) into which the bus bar (23) is fitted is formed.   The bus bars (23a, 23b) are respectively connected to the two electrode portions (22a, 22b) formed on the capacitor element (21), and both the two bus bars (23a, 23b) are connected to each other. The power converter according to claim 1, wherein a part of the power converter is interposed between the electrode part (22) and the heat dissipation member (3). (1).

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