Cooling device for connecting conductors

Abstract

To obtain a cooling device of a connection conductor in which, even when connection conductors are provided at different heights from a cooler in a plurality of electric components, the connection conductors are electrically connected to each other without performing bending processing for adjusting the heights of connection portions of the connection conductors to each other on the connection conductors, and the connection conductors are cooled.SOLUTION: The cooling device 100 for connection conductors includes a cooler 1, a first connection conductor 4 provided in a first electrical component 2, a second connection conductor 5 provided in a second electrical component 3 and electrically connected to the first connection conductor 4, and a spacer 6 provided between the first connection conductor 4 and the second connection conductor 5 and electrically connecting the first connection conductor 4 and the second connection conductor 5, wherein the first connection conductor 4 is sandwiched between the cooler 1 and the spacer 6.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a cooling device for a connecting conductor. [Background technology]

[0002] Conventional power conversion devices, such as inverters or converters, that convert high power include switching modules with semiconductor switching elements and electrical components, such as capacitors and connectors, electrically connected to the switching modules. The switching modules and electrical components are electrically connected through connecting conductors provided thereto. The semiconductor switching elements used in such high-power power conversion generate a large amount of heat during operation, and this heat may be transferred to the electrical components via the connecting conductors, causing the temperature of the electrical components to rise. Furthermore, large currents may flow through the connecting conductors provided in the semiconductor switching elements and electrical components used in such high-power power conversion. This current may heat the connecting conductors, which may then cause the temperature of the semiconductor switching elements and electrical components to rise. Temperature increases in electrical components, such as capacitors and connectors, can lead to performance degradation or damage due to temperatures exceeding their heat resistance. Therefore, suppressing excessive temperature increases contributes to preventing shortened lifespans and improving reliability of electrical components. Not only power conversion devices, but also devices equipped with electrical components, when in operation, generate heat from the electrical components and the connecting conductors that connect the electrical components together. It is desirable to prevent the heat generated in the electrical components from being transferred to other electrical components, or to prevent the heat generated in the connecting conductors from adversely affecting the connecting conductors themselves or the electrical components.

[0003] One possible way to suppress the effects of heat generated in electrical components and connecting conductors is to cool the connecting conductors. For example, Patent Document 1 discloses a cooling device for cooling connecting conductors provided in electrical components, in which connecting conductors provided in electrical components that are electrically connected are arranged to overlap each other, a heat transfer body is fastened to the connecting portion where the connecting conductors overlap, and heat from the connecting conductors is transferred to a cooler via the heat transfer body, thereby cooling the connecting conductors. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-84609 Summary of the Invention [Problem to be solved by the invention]

[0005] In the conventional cooling device described above, in order to electrically connect the connection conductors of different electrical components, the connection portions of the connection conductors must be arranged so that they overlap. Therefore, if the heights of the connection conductors from the cooler are the same, the connection portions can be arranged so that they overlap. However, the heights of the different electrical components are often not the same. When the connection conductors of the different electrical components that are electrically connected are different in height, it is necessary to bend one or both of the connection conductors to align the heights of the connection portions that are arranged so that they overlap. However, such bending increases the complexity of the manufacturing process and the number of manufacturing steps.

[0006] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a cooling device for connection conductors in which, even if connection conductors are provided in multiple electrical components at different heights from a cooler, the connection conductors are electrically connected to each other without performing bending processing to match the heights of the connection portions of each connection conductor, and the connection conductors are cooled. [Means for solving the problem]

[0007] The cooling device for a connecting conductor according to the present disclosure comprises a cooler, a first connecting conductor provided on a first electrical component, a second connecting conductor provided on a second electrical component and electrically connected to the first connecting conductor, and a spacer provided between the first connecting conductor and the second connecting conductor and electrically connecting the first connecting conductor and the second connecting conductor, with the first connecting conductor sandwiched between the cooler and the spacer. [Effects of the Invention]

[0008] According to the present disclosure, a spacer is provided between the first connecting conductor and the second connecting conductor, electrically connecting the first connecting conductor and the second connecting conductor, and by filling the space between the first connecting conductor and the second connecting conductor with the spacer, the connecting conductors located at different heights from the cooler are electrically connected without performing bending processing to match the heights of the connection portions of each connecting conductor, and further, since the first connecting conductor is sandwiched between the spacer and the cooler, a cooling device can be obtained in which the heat of the first connecting conductor is transferred to the cooler and the first connecting conductor is cooled. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view showing a cooling device for a connecting conductor according to a first embodiment and a main part of a power converter using the cooling device for the connecting conductor; FIG. [Figure 2] 2 is a cross-sectional view of the cooling device for the connecting conductor shown in FIG. [Figure 3] 2 is an exploded perspective view of the cooling device for the connecting conductor shown in FIG. 1; [Figure 4] 1 is a cross-sectional view of a cooling device for a connecting conductor in a case where a spacer is a cap nut in the first embodiment; [Figure 5] 10 is a cross-sectional view of a cooling device for a connecting conductor according to a second embodiment. [Figure 6] 10 is a cross-sectional view of a cooling device for a connecting conductor according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Embodiment 1 The connecting conductor cooling device 100 of embodiment 1 is mounted on a power conversion device, electrically connects the connecting conductors of different electrical components provided in the power conversion device, and further cools either one or both of the connecting conductors. The configuration of the cooling device 100 for a connecting conductor according to the first embodiment will be described below with reference to FIGS.

[0011] Figure 1 is an oblique view showing a part of a power conversion device using a connecting conductor cooling device 100 relating to embodiment 1, Figure 2 is a cross-sectional view showing a part of the connecting conductor cooling device 100 and the power conversion device shown in Figure 1, and Figure 3 is an exploded oblique view showing a part of the connecting conductor cooling device 100 and the power conversion device shown in Figure 1. The power conversion device is, for example, an inverter or a converter, and includes various electrical components for power conversion. The power conversion device shown in Fig. 1 includes a switching module 2 as a first electrical component and a capacitor 3 as a second electrical component.

[0012] The switching module 2 has a semiconductor switching element 21 therein for power conversion operation, and a first connecting conductor 4 connected to this internal semiconductor switching element 21 and exposed to the outside of the switching module 2. The capacitor 3 also has a second connecting conductor 5 exposed to the outside of the body, and by electrically connecting this second connecting conductor 5 to the first connecting conductor 4 of the switching module 2, the capacitor 3 functions to smooth the power output from the switching module 2 when the power conversion device is operating. A spacer 6 is disposed between the first connecting conductor 4 and the second connecting conductor 5, electrically connecting the first connecting conductor 4 and the second connecting conductor 5 and filling the gap between the first connecting conductor 4 and the second connecting conductor 5. The spacer 6 is made of a material with good electrical and thermal conductivity.

[0013] The cooler 1 receives heat from electrical components such as a switching module 2 and a capacitor 3 provided in the power conversion device, or from the connecting conductors provided thereon, and dissipates the heat to the outside of the power conversion device, and is, for example, a heat sink made of aluminum die-casting. The above-described cooler 1, the first connecting conductor 4 provided in the switching module 2, the second connecting conductor 5 provided in the capacitor 3 and electrically connected to the first connecting conductor 4, and the spacer 6 provided between the first connecting conductor 4 and the second connecting conductor 5 and electrically connecting the first connecting conductor 4 and the second connecting conductor 5 constitute a connecting conductor cooling device 100 that dissipates heat from the connecting conductors provided in electrical components such as the switching module 2 and the capacitor 3 to the outside of the power conversion device. The configuration will be described in more detail below.

[0014] The cooler 1 is a heat sink having a flat surface 11 on one side, and this surface 11 has a screw hole 12 for a holding member formed therein for fastening a screw 10 for fixing a holding member 7 that holds a spacer 6.

[0015] The switching module 2 is composed of a base plate portion 22, a substrate portion 23 attached to the base plate portion 22, a semiconductor switching element 21 attached to the substrate portion 23, a first connecting conductor 4 electrically connected to the semiconductor switching element 21 by wire bonding or the like, and a molded resin portion 24 that molds a portion of the base plate portion 22, the substrate portion 23, the semiconductor switching element 21, and a portion of the first connecting conductor 4 together to form them into a single unit. Base plate portion 22 dissipates heat generated during operation of semiconductor switching element 21, and is generally made of a plate-like material such as copper, which has low thermal resistance. To dissipate this heat, base plate portion 22 is molded in molded resin portion 24 with the surface opposite to the surface on which substrate portion 23 is attached exposed. The switching module 2 is attached to the cooler 1 with the surface of the base plate 22 exposed from the molded resin portion 24 in contact with the surface 11 of the cooler 1. In order to improve the heat dissipation of the semiconductor switching elements 21, heat-dissipating grease may be applied to the surface of the base plate 22 exposed from the molded resin portion 24 before the switching module 2 is attached to the cooler 1.

[0016] The first connecting conductor 4 electrically connects the switching module 2 to other electrical components, is made of a conductive material such as copper, is a strip-shaped bus bar extending in a direction parallel to the surface 11 of the cooler 1 on which the switching module 2 and capacitor 3 are mounted, and has a first connecting portion 41 at its tip. The first connecting conductor 4 is sandwiched between the cooler 1 and the spacer 6 together with an electrically insulating heat-transfer material 8 that electrically insulates the first connecting conductor 4 from the cooler 1 .

[0017] The capacitor 3 is attached to the surface 11 of the cooler 1. The capacitor 3 has a second connecting conductor 5 on its side surface. The second connecting conductor 5 is made of a conductive material such as copper, and is a strip-shaped bus bar that extends in a direction parallel to the surface 11 when the capacitor 3 is attached to the surface 11 of the cooler 1, and has a second connecting portion 51 with a fastening hole at its tip. Here, the first connecting conductor 4 and the second connecting conductor 5 need to be electrically connected to each other, and although they overlap in top view, they are spaced apart and have different heights from the surface 11 of the cooler 1. Here, the height from the surface 11 of the cooler 1 refers to the distance from the surface 11 in the normal direction to the surface 11.

[0018] The spacer 6 is a cylindrical member made of a conductive material such as copper, aluminum, or an alloy thereof, and is a nut having a through-hole 61 for fastening the second connecting conductor 5 with a screw 9. The spacer 6 is held by the holding member 7 by being molded integrally with the holding member 7 by insert molding. The holding member 7 has a holding portion 71 that holds the spacer 6 and a fixing portion 72 for attaching the holding member 7 to the cooler 1. The fixing portion 72 has a hole 73 formed therein through which a screw 10 is inserted that is fastened to the holding member screw hole 12 of the cooler 1 when attaching the holding member 7 to the cooler 1. The holding portion 71 and the fixing portion 72 are made of molded resin, and the spacer 6, holding portion 71, and fixing portion 72 are molded integrally by insert molding in which the spacer 6 is embedded. The screw 10 inserted into the hole 73 is fastened to the holding member screw hole 12 of the cooler 1, thereby fixing the holding member 7 and the spacer 6 molded integrally with the holding member 7 to the cooler 1.

[0019] In the cooling device 100 for the connecting conductor, one surface of the spacer 6 presses the first connecting part 41 against the cooler 1 via the electrically insulating heat transfer material 8, and a screw 10 inserted into a hole in the fixing part 72 is fastened to the screw hole 12 for the holding member, whereby the spacer 6 and the cooler 1 clamp the first connecting conductor 4 and electrically connect the spacer 6 and the first connecting conductor 4. In addition, with the second connection portion 51 of the second connecting conductor 5 in contact with the other surface of the spacer 6, a screw 9 inserted into a hole in the second connection portion 51 is fastened to the screw hole 61 of the spacer 6, thereby fixing the spacer 6 to the second connection portion 51 of the second connecting conductor 5 and electrically connecting the spacer 6 to the second connection portion 51. With the above-described configuration, the first connecting conductor 4 and the second connecting conductor 5 are electrically connected via the spacer 6 that fills the gap between the first connecting conductor 4 and the second connecting conductor 5. Because the gap between the first connecting conductor 4 and the second connecting conductor 5 is filled by the spacer 6, the first connecting conductor 4 and the second connecting conductor 5 are electrically connected without bending the first connecting conductor 4 and the second connecting conductor 5, which are at different heights from the cooler 1.

[0020] The electrically insulating heat-transfer material 8 is provided between the first connecting conductor 4 and the cooler 1 to electrically insulate the first connecting conductor 4 from the cooler 1 and to dissipate heat from the first connecting conductor 4 to the cooler 1. In the first embodiment, an elastic insulating heat-dissipating member is used as the electrically insulating heat-transfer material 8. The electrically insulating heat-transfer material 8 is sandwiched between the spacer 6 and the first connecting conductor 4 and the cooler 1 in an elastically deformed state.

[0021] Next, the operation of the cooling device 100 for a connecting conductor configured as above will be described. When a power conversion device including the connecting conductor cooling device 100 performs power conversion, the semiconductor switching element 21 performs a switching operation. The first connecting conductor 4 connected to the semiconductor switching element 21 and the second connecting conductor 5 included in the capacitor 3 are electrically connected by the spacer 6, so that the capacitor 3 smoothes the power ripple generated by the switching operation of the semiconductor switching element 21. Next, the heat dissipation effect of the cooling device 100 for the connecting conductor will be described. When this power conversion device performs power conversion, the semiconductor switching elements 21 that perform the switching operation generate heat. The heat generated by this heat is transferred to the cooler 1 via the substrate portion 23 and base plate portion 22 of the switching module 2, and is then radiated from the cooler 1 to the external space. However, some of the heat is also transferred to the first connecting conductor 4 provided in the switching module 2, causing the temperature of the first connecting conductor 4 to rise. On the other hand, when the capacitor 3 smooths the power output from the switching module 2, power is exchanged between the switching module 2 and the capacitor 3 via the first connecting conductor 4, the spacer 6 and the second connecting conductor 5, and this current flow causes the first connecting conductor 4 and the second connecting conductor 5 to generate heat. As described above, the temperature of the first connecting conductor 4 rises due to heat transfer from the switching module 2 and heat generation accompanying current flow. The temperature rise of the first connecting conductor 4 is undesirable because it can lead to performance degradation and damage to surrounding electrical components such as the capacitor 3 and connectors. In contrast, in the connecting conductor cooling device 100, the first connecting conductor 4 is sandwiched between the cooler 1 and the spacer 6 while being pressed against the cooler 1 via the electrically insulating heat transfer material 8. Therefore, the heat of the first connecting conductor 4 is dissipated to the cooler 1 via the electrically insulating heat transfer material 8, thereby cooling the first connecting conductor 4 and suppressing an excessive temperature rise of the first connecting conductor 4.

[0022] In addition, when the capacitor 3 smooths the power ripple generated by the switching operation of the semiconductor switching element 21, the capacitor 3 also generates heat. Although this heat is generally smaller than the heat generated by the switching operation of the semiconductor switching element 21, it is transferred to the second connecting conductor 5 provided in the capacitor 3, and the second connecting conductor 5 further generates heat due to the power exchanged between the switching module 2 and the capacitor 3, and this heat causes the temperature of the second connecting conductor 5 to rise. In this way, the temperature of the second connecting conductor 5 rises due to the heat transfer from the capacitor 3 and the heat generated by the current flow. The spacer 6 to which the second connecting portion 51 of the second connecting conductor 5 is fixed is made of a conductive material such as copper or aluminum, or an alloy thereof, and since these materials have low thermal resistance, the heat of the second connecting conductor 5 is transferred to the spacer 6 and dissipated to the cooler 1 via the first connecting conductor 4 and the electrically insulating heat transfer material 8, thereby cooling the second connecting conductor 5 and preventing an excessive temperature rise in the second connecting conductor 5.

[0023] As described above, in the cooling device 100 for a connecting conductor according to embodiment 1, the spacer 6 electrically connects the first connecting conductor 4 and the second connecting conductor 5, which are at different heights from the surface of the cooler 1, while the first connecting conductor 4 is sandwiched between the spacer 6 and the cooler 1 via the electrically insulating heat transfer material 8. Therefore, the first connecting conductor 4 and the second connecting conductor 5, which are at different heights from the cooler 1, can be electrically connected without requiring bending processing to match the heights of the first connecting portion 41 and the second connecting portion 51 from the cooler 1, and the first connecting conductor 4 can be cooled by dissipating heat from the first connecting conductor 4 to the cooler 1. In the first embodiment, the first connecting conductor 4 and the second connecting conductor 5 extend parallel to the surface 11 of the cooler 1 from the switching module 2 and the capacitor 3, respectively. That is, the first connecting conductor 4 does not have a bent portion exposed from the molded resin portion 24 that forms the outer periphery of the main body of the switching module 2, and the second connecting conductor 5 does not have a bent portion exposed from the main body of the capacitor 3. According to the cooling device 100 for connecting conductors of the first embodiment, the first connecting conductor 4 and the second connecting conductor 5, which are at different heights from the surface 11 of the cooler 1, are electrically connected without having to bend the portion of the first connecting conductor 4 exposed from the molded resin portion 24 and the portion of the second connecting conductor 5 exposed from the main body of the capacitor 3. This makes it possible to cool the first connecting conductor 4 by dissipating heat from the first connecting conductor 4 to the cooler 1, thereby preventing the manufacturing process from becoming more complicated and the number of manufacturing steps from increasing. Furthermore, switching modules generally generate more heat during operation and have a higher rated temperature than other components included in the power conversion device. In the first embodiment, even if the switching module 2 included in the power conversion device has a higher rated temperature than the capacitor 3 and becomes hotter during operation, the heat from the switching module 2 transferred to the first connecting conductor 4 is dissipated to the cooler 1 via the electrically insulating heat-transfer material 8, thereby suppressing the amount of heat transferred to the second connecting conductor 5 and suppressing the temperature rise of the capacitor 3. In such a case, to prevent the temperature of the capacitor 3 from approaching the temperature of the switching module 2 during operation and exceeding the rated temperature of the capacitor 3 due to the heat transfer from the switching module 2 to the capacitor 3, it is preferable that the thermal resistance of the heat path from the first connecting conductor 4 to the cooler 1 be lower than the thermal resistance of the heat path from the first connecting conductor 4 to the second connecting conductor 5. In this way, in a cooling device for a connecting conductor in which the thermal resistance of the heat path from the first connecting conductor 4 to the cooler 1 is lower than the thermal resistance of the heat path from the first connecting conductor 4 to the second connecting conductor 5, the heat generated in the switching module 2 is more effectively prevented from being transferred to the capacitor 3, causing the temperature of the capacitor 3 to rise and causing the capacitor 3 to exceed its rated temperature, resulting in performance degradation or damage, compared to when the thermal resistance of the heat path from the first connecting conductor 4 to the cooler 1 is higher than the thermal resistance of the heat path from the first connecting conductor 4 to the second connecting conductor 5. Generally, the switching module generates more heat as the power it converts increases. Therefore, according to the configuration of the connecting conductor cooling device 100 of embodiment 1, there is no need to limit the power converted by the switching module 2 in order to prevent the heat of the switching module 2 from being transferred to the capacitor 3 and causing the temperature of the capacitor 3 to exceed the rated temperature, and the power conversion device can convert greater power.

[0024] Moreover, the cooler 1 is generally made of a conductive material such as aluminum, which has high heat dissipation properties. Because these materials are conductive, electrical insulation is required between the first connecting conductor 4 and the cooler 1. For this electrical insulation, it is preferable to provide an electrically insulating heat-transfer material 8 between the first connecting conductor 4 and the cooler 1. Furthermore, in the first embodiment, the electrically insulating heat-transfer material 8 is made of an elastic insulating heat-dissipating material. In this case, when the holding member 7 that holds the spacer 6 is assembled to the cooler 1 so that the electrically insulating heat-transfer material 8 and the first connecting conductor 4 are sandwiched between the spacer 6 and the cooler 1, the screws 10 are tightened to an extent that the electrically insulating heat-transfer material 8 is elastically deformed, and the elasticity of the electrically insulating heat-transfer material 8 generates a pressing force that presses the first connecting conductor 4 toward the spacer 6. Therefore, even if dimensional variations occur in the normal direction of the surface 11 of the cooler 1 when assembling the switching module 2 including the first connecting conductor 4 and the holding member 7 that holds the spacer 6 to the cooler 1, the first connecting conductor 4 is pressed against the spacer 6, thereby ensuring contact between the first connecting conductor 4 and the spacer 6 and preventing poor contact or an increase in power loss due to increased contact resistance. Furthermore, ensuring contact between the electrically insulating heat-transfer material 8 and the first connecting conductor 4 allows for more efficient heat dissipation from the first connecting conductor 4 to the cooler 1.

[0025] Furthermore, in embodiment 1, the spacer 6 is a nut, and the cooling device 100 for the connecting conductor can be assembled by assembling a holding member 7 that holds the spacer 6 from above the switching module 2 mounted on the surface 11 of the cooler 1, assembling the capacitor 3 from above that, and tightening the screw 9 inserted into the hole of the second connection portion 51 of the second connecting conductor 5 into the screw hole 61 of the spacer 6. In this way, the assembly of the cooling device 100 for the connecting conductor can be easily performed by assembling all the components from above in the normal direction of the surface 11 of the cooler 1. Furthermore, the spacer 6 and the second connecting conductor 5 need to be in contact with each other for electrical connection, and it is preferable that the spacer 6 and the second connecting conductor 5 are fixed to each other. In the first embodiment, the spacer 6 is a nut, and the second connecting portion 51 is fixed to the spacer 6 by a screw 9, which makes it easy to disassemble after assembly. Furthermore, the holding member 7 is fixed to the cooler 1 by fastening screws 9 inserted into holes 73 of the fixing portions 72 to holding member screw holes 12 of the cooler 1. Therefore, the holding member 7 can be easily disassembled after being assembled to the cooler 1. Furthermore, the spacer 6 and the holding member 7 are molded as a single unit and serve as a terminal block that electrically connects the first connecting conductor 4 and the second connecting conductor 5. By fixing the holding member 7 to the cooler 1, the first connecting conductor 4 is clamped between the spacer 6 and the cooler 1, allowing the heat of the first connecting conductor 4 to be dissipated to the cooler 1. Therefore, the number of parts can be reduced and assembly is easier than when a terminal block that electrically connects the connecting conductors to each other and a part that dissipates the heat of the connecting conductors to the cooler 1 are provided separately. Furthermore, since the holding portion 71 is made of resin, which is an insulating material, the spacer 6 can be insulated from other surrounding components such as the cooler 1 that are made of conductive materials.

[0026] In the first embodiment, the second electric component is described as a capacitor, but the second electric component may be a coil component such as a reactor. In this case, as in the first embodiment, a temperature rise in the coil component, which is the second electric component, can be suppressed during operation of the switching module 2, and therefore it is possible to prevent a rise in the temperature of the coil component, which is the second electric component, from increasing its electrical resistance, which in turn increases power consumption, or to prevent deterioration of the insulating coating of the coil component.

[0027] Furthermore, in the above-described first embodiment, the spacer 6 is described as a nut having the screw hole 61 passing therethrough, but the spacer 6 may be a cap nut having the screw hole 61 not passing therethrough. FIG. 4 is a cross-sectional view showing a portion of the connecting conductor cooling device 100 and the power converter according to the first embodiment when the spacer 6 is a cap nut. When the spacer 6 is a cap nut without a through-threaded screw hole 61, metal particles generated by friction between the screw 9 and the threaded hole 61 during tightening of the screw 9 remain inside the threaded hole 61, preventing the metal particles from coming into contact with connecting components of the electrical circuit provided in the power converter and causing a short circuit. Furthermore, the contact area between the spacer 6 and the first connecting portion 41 of the first connecting conductor 4 can be secured larger than when the threaded hole 61 is through-threaded, thereby reducing electrical contact resistance. Furthermore, even if the spacer 6 and the first connecting portion 41 are misaligned in a direction parallel to the surface 11 of the cooler 1 during assembly, the contact area can be secured. Therefore, high precision is not required for aligning the spacer 6 and the first connecting portion 41 during assembly, thereby reducing costs in the assembly process.

[0028] Embodiment 2 In the first embodiment, the first electrical component is a switching module, the second electrical component is a capacitor, and the switching module, which is the first electrical component, generates more heat during operation and has a higher rated temperature than the capacitor, which is the second electrical component. In this case, the heat generated in the switching module 2 is transferred to the cooler 1 via the electrically insulating heat transfer material 8 and dissipated, thereby reducing the amount of heat transferred to the second connecting conductor 5. In the second embodiment, a second electric component generates more heat during operation and has a higher rated temperature than the first electric component. The cooling device for a connecting conductor according to the second embodiment can suppress the amount of heat transferred from the second electric component to the first electric component, thereby preventing the temperature of the first electric component from rising excessively. FIG. 5 is a cross-sectional view showing a cooling device for a connecting conductor according to the second embodiment. In the cooling device 100 for a connecting conductor according to the second embodiment, the second electric component 3a generates more heat during operation and has a higher rated temperature than the first electric component 2a. Here, the first electric component 2a is, for example, a planar transformer, and the second electric component 3a is, for example, a switching module. Other configurations of the cooling device 100 for a connecting conductor according to the second embodiment are the same as those of the first embodiment.

[0029] In the cooling device 100 of embodiment 2, the heat generated by the second electrical component 3a is transferred to the second connecting conductor 5, the spacer 6, and the first connecting portion 41, and a portion of the heat is transferred to the cooler 1 via the electrically insulating heat transfer material 8 and dissipated into the external space, and another portion is transferred to the main body of the first electrical component 2a via the first connecting conductor 4. In such a case, in order to prevent the temperature of the first electrical component 2a from approaching the temperature of the second electrical component 3a in operation and exceeding the rated temperature of the first electrical component 2a due to the heat being transferred from the second electrical component 3a to the first electrical component 2a, it is preferable that the thermal resistance of the heat path from the second connecting conductor 5 to the cooler 1 be lower than the thermal resistance of the heat path from the second connecting conductor 5 to the main body of the first electrical component 2a via the spacer 6 and the first connecting conductor 4. In this way, in the connecting conductor cooling device 100, in which the thermal resistance of the heat path from the second connecting conductor 5 to the cooler 1 is configured to be lower than the thermal resistance of the heat path from the second connecting conductor 5 to the main body of the first electrical component 2a via the spacer 6 and the first connecting conductor 4, it is possible to more effectively prevent heat generated in the second electrical component 3a from being transferred to the first electrical component 2a, causing the temperature of the first electrical component 2a to rise and causing the first electrical component 2a to exceed its rated temperature, resulting in performance degradation or damage, compared to when the thermal resistance of the heat path from the second connecting conductor 5 to the cooler 1 is higher than the thermal resistance of the heat path from the second connecting conductor 5 to the main body of the first electrical component 2a via the spacer 6 and the first connecting conductor 4.

[0030] Furthermore, according to the configuration of the connecting conductor cooling device 100 of embodiment 2, there is no need to restrict the operation that causes the second electrical component 3a to generate heat in order to prevent the heat of the second electrical component 3a from being transferred to the first electrical component 2a and causing the temperature of the first electrical component 2a to exceed the rated temperature, and the performance of the equipment equipped with the connecting conductor cooling device 100 can be improved.

[0031] Embodiment 3 FIG. 6 is a cross-sectional view showing a cooling device for a connecting conductor according to the third embodiment. The cooling device 100 for a connecting conductor according to the third embodiment is different from the cooling device 100 of the first embodiment in the configuration of the spacer 6, but is otherwise similar to the cooling device 100 of the first embodiment. The spacer 6 includes a nut portion 62 having a screw hole 61 formed on the side of the second connecting conductor 5, and a spring portion 63 fixed to the nut portion 62 on the side of the first connecting conductor 4. In the third embodiment, the holding portion 71 of the holding member 7 is molded integrally with the spacer 6 while holding the outer periphery of the nut portion 62. In embodiment 3, a holding member 7 that holds the spacer 6 is attached to the cooler 1 so that the first connecting conductor 4 and the electrically insulating heat transfer material 8 are sandwiched between the spring portion 63 of the spacer 6 and the cooler 1 when the spring portion 63 of the spacer 6 is elastically deformed to compress.

[0032] In embodiment 3, when the spring portion 63 of the spacer 6 is elastically deformed to compress, a holding member 7 that holds the spacer 6 is attached to the cooler 1 so that the first connecting conductor 4 and the electrically insulating heat transfer material 8 are sandwiched between the spring portion 63 of the spacer 6 and the cooler 1, and the elasticity of the spring portion 63 generates a pressing force that presses the first connecting conductor 4 toward the electrically insulating heat transfer material 8. As a result, the spring portion 63 is pressed against the first connecting portion 41 of the first connecting conductor 4, and the first connecting conductor 4 is pressed against the electrically insulating heat transfer material 8, thereby ensuring contact between the first connecting conductor 4 and the spacer 6 and preventing poor contact or an increase in power loss due to increased contact resistance.In addition, by ensuring contact between the electrically insulating heat transfer material 8 and the first connecting conductor 4, heat can be dissipated from the first connecting conductor 4 to the cooler 1 more efficiently.

[0033] In all of the above embodiments, the cooler 1 has been described as a heat sink made of aluminum die-cast, but the form of the cooler 1 is not particularly limited, and it may be, for example, a part of the housing that constitutes the power conversion device, or it may be a cooler that uses a heat pipe and heat dissipation means, or a cooler that circulates a fluid such as a liquid between the cooler and the heat sink, and any other known technology may be appropriately selected and used.

[0034] In addition, in all of the above embodiments, an elastic insulating heat-transfer material is used as the electrically insulating heat-transfer material 8, but as long as the electrically insulating heat-transfer material 8 can electrically insulate the first connecting conductor 4 from the cooler 1 while transferring heat from the first connecting conductor 4 to the cooler 1, it is also possible to use a material constructed using other known methods, such as coating the surface of the first connecting conductor 4 facing the cooler 1 with an insulating resin film and applying heat-dissipating grease between the insulating resin film and the cooler 1.

[0035] Furthermore, in all of the above embodiments, the second connecting conductor 5 is fixed to the spacer 6 by fastening the screw 9 into the screw hole 61 of the spacer 6, but the means for fixing the second connecting conductor 5 to the spacer 6 is not limited to this. For example, without forming a screw hole in the spacer 6, the second connecting conductor 5 and the spacer 6 may be fixed by welding or other welding. In this case, compared to when a screw hole is formed in the spacer 6, a larger contact area can be secured between the spacer 6 and the second connecting conductor 5, reducing contact resistance to prevent power loss and also reducing thermal resistance between the second connecting conductor 5 and the spacer 6. Furthermore, by welding the second connecting conductor 5 and the spacer 6, a molten part is formed between the second connecting conductor 5 and the spacer 6, reducing contact resistance to prevent power loss and also reducing thermal resistance between the second connecting conductor 5 and the spacer 6.

[0036] Furthermore, in all of the above embodiments, the description has been given of the connecting conductor cooling device 100 being mounted on a power converter, but it goes without saying that the present invention is not limited to this and can be used in cases where the heights of the connecting conductors provided on different electrically connected electrical components from the respective coolers are different.

[0037] It should be noted that the technical ideas shown in the embodiments may be included in the scope of the embodiments by appropriately combining, modifying, or omitting the above-described embodiments.

[0038] Various aspects of the present disclosure will be summarized below as appendices. (Appendix 1) A cooler; a first connecting conductor provided on the first electrical component; a second connecting conductor provided in a second electrical component and electrically connected to the first connecting conductor; a spacer provided between the first connection conductor and the second connection conductor, electrically connecting the first connection conductor and the second connection conductor; The first connecting conductor is sandwiched between the cooler and the spacer. Cooling device for connecting conductors. (Appendix 2) The first electric component generates more heat during operation than the second electric component. 10. A cooling device for a connecting conductor as described in Appendix 1. (Appendix 3) The first electrical component has a higher rated temperature than the second electrical component. 3. A cooling device for a connecting conductor according to claim 1 or 2. (Appendix 4) The thermal resistance of the heat path from the first connecting conductor to the cooler is smaller than the thermal resistance of the heat path from the first connecting conductor to the second connecting conductor. 4. A cooling device for a connecting conductor according to claim 2 or 3. (Appendix 5) The first electrical component is a switching module equipped with a semiconductor switching element. 5. A cooling device for a connecting conductor according to any one of claims 1 to 4. (Appendix 6) The second electric component generates more heat during operation than the first electric component. 10. A cooling device for a connecting conductor as described in Appendix 1. (Appendix 7) The second electrical component has a higher rated temperature than the first electrical component. 10. A cooling device for a connecting conductor according to claim 1 or 6. (Appendix 8) The thermal resistance of the heat path from the second connecting conductor to the cooler is smaller than the thermal resistance of the heat path from the second connecting conductor to the main body of the first electric component. 8. A cooling device for a connecting conductor according to claim 6 or 7. (Appendix 9) the first connecting conductor has a strip shape extending parallel to a surface of the cooler in a portion exposed from a main body of the first electric component, the second connecting conductor has a strip shape extending parallel to a surface of the cooler in a portion exposed from a main body of the second electric component, The first connecting conductor and the second connecting conductor are at different heights from the cooler. 9. A cooling device for a connecting conductor according to any one of appendices 1 to 8. (Appendix 10) An electrically insulating and heat-conductive material is provided between the first connecting conductor and the cooler. 11. A cooling device for a connecting conductor according to any one of claims 1 to 10. (Appendix 11) The electrically insulating and heat conducting material has elasticity. 11. A cooling device for a connecting conductor according to claim 10. (Appendix 12) The second connecting conductor and the spacer are fixed to each other. 13. A cooling device for a connecting conductor according to any one of appendices 1 to 12. (Appendix 13) The second connecting conductor is fixed to the spacer by being welded to the spacer. 13. A cooling device for a connecting conductor according to claim 12. (Appendix 14) the spacer is a nut having a threaded hole; The second connecting conductor is fixed by a screw fastened in the screw hole. 13. A cooling device for a connecting conductor according to claim 12. (Appendix 15) The spacer is a cap nut with one end of the screw hole closed. 15. A cooling device for a connecting conductor according to claim 14. (Appendix 16) The spacer is molded integrally with the holding member, The holding member is attached to the cooler. 16. A cooling device for a connecting conductor according to any one of appendixes 1 to 15. (Appendix 17) The holding member is made of an insulating material. 17. A cooling device for a connecting conductor according to claim 16. (Appendix 18) the cooler has a screw hole for a holding member, the holding member includes a fixing portion for inserting a screw therethrough; The holding member is attached to the cooler by fastening a screw inserted into the fixing portion to the holding member screw hole. 18. A cooling device for a connecting conductor according to claim 16 or 17. (Appendix 19) The spacer has an elastically deformable spring portion. 19. A cooling device for a connecting conductor according to any one of appendixes 1 to 18. (Appendix 20) The second electrical component is a capacitor. 20. A cooling device for a connecting conductor according to any one of appendixes 1 to 19. (Appendix 21) The second electrical component is a coil component. 20. A cooling device for a connecting conductor according to any one of appendixes 1 to 19. [Explanation of symbols]

[0039] 100 Cooling device for connecting conductor 1 cooler 2. Switching module (first electrical component) 21 Semiconductor switching element 22 Base plate 23 Circuit board section 24 Molded resin part 3. Capacitor (secondary electrical component) 4. First connecting conductor 41 First connection 5 Second connecting conductor 51 Second connection 6 spacers 7 Retaining member 71 Holding part 72 Fixed part 8 Electrical insulating and heat conducting materials 2a First Electrical Component 3a Secondary Electrical Part

Claims

1. A cooler; a first connecting conductor provided on the first electrical component; a second connecting conductor provided in a second electrical component and electrically connected to the first connecting conductor; a spacer provided between the first connection conductor and the second connection conductor, electrically connecting the first connection conductor and the second connection conductor; The first connecting conductor is sandwiched between the cooler and the spacer. Cooling device for connecting conductors.

2. The first electric component generates more heat during operation than the second electric component. The cooling device for a connecting conductor according to claim 1 .

3. The first electrical component has a higher rated temperature than the second electrical component. The cooling device for a connecting conductor according to claim 1 .

4. The thermal resistance of the heat path from the first connecting conductor to the cooler is smaller than the thermal resistance of the heat path from the first connecting conductor to the second connecting conductor. The cooling device for a connecting conductor according to claim 2 or 3.

5. The first electrical component is a switching module equipped with a semiconductor switching element. The cooling device for a connecting conductor according to claim 2 or 3.

6. The second electric component generates more heat during operation than the first electric component. The cooling device for a connecting conductor according to claim 1 .

7. The second electrical component has a higher rated temperature than the first electrical component. The cooling device for a connecting conductor according to claim 1 .

8. The thermal resistance of the heat path from the second connecting conductor to the cooler is smaller than the thermal resistance of the heat path from the second connecting conductor to the main body of the first electric component. The cooling device for a connecting conductor according to claim 6 or 7.

9. the first connecting conductor has a strip shape extending parallel to a surface of the cooler in a portion exposed from a main body of the first electric component, the second connecting conductor has a strip shape extending parallel to a surface of the cooler in a portion exposed from a main body of the second electric component, The first connecting conductor and the second connecting conductor are at different heights from the cooler. The cooling device for a connecting conductor according to claim 1 .

10. An electrically insulating and heat-conductive material is provided between the first connecting conductor and the cooler. The cooling device for a connecting conductor according to claim 1 .

11. The electrically insulating and heat conducting material has elasticity. The cooling device for a connecting conductor according to claim 10.

12. The second connecting conductor and the spacer are fixed to each other. The cooling device for a connecting conductor according to claim 1 .

13. The second connecting conductor is fixed to the spacer by being welded to the spacer. The cooling device for a connecting conductor according to claim 12.

14. the spacer is a nut having a threaded hole; The second connecting conductor is fixed by a screw fastened in the screw hole. The cooling device for a connecting conductor according to claim 12.

15. The spacer is a cap nut with one end of the screw hole closed. The cooling device for a connecting conductor according to claim 14.

16. The spacer is molded integrally with the holding member, The holding member is attached to the cooler. The cooling device for a connecting conductor according to claim 1 .

17. The holding member is made of an insulating material. The cooling device for a connecting conductor according to claim 16.

18. the cooler has a screw hole for a holding member, the holding member includes a fixing portion for inserting a screw therethrough; The holding member is attached to the cooler by fastening a screw inserted into the fixing portion to the holding member screw hole.

18. The cooling device for a connecting conductor according to claim 16 or 17.

19. The spacer has an elastically deformable spring portion. The cooling device for a connecting conductor according to claim 1 .

20. The second electrical component is a capacitor. The cooling device for a connecting conductor according to claim 1 .

21. The second electrical component is a coil component. The cooling device for a connecting conductor according to claim 1 .

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