Inverter unit and gasket for inverter unit

Abstract

The inside and the outside of an inverter unit of a power conversion device according to the present embodiment are partitioned by a partition plate. The partition plate is provided with a round hole, and a cylindrical capacitor case is threaded through the round hole. A gap between the edge of the round hole in the partition plate and the capacitor case threaded through the round hole is filled by a gasket. The gasket is formed from a base and a membrane. The base and the membrane are of a single piece. The base has a circular shape and the edges thereof are pinched from the front and back when mounted in the round hole. The membrane extends from the base mounted in the round hole toward the center of the round hole and adheres to the circumferential surface of the capacitor case threaded through the round hole.

Description

Technical Field

[0001] The present disclosure relates to an inverter unit of a power conversion device and a packing for the inverter unit.

Background Art

[0002] The inverter unit of a power conversion device includes a capacitor. Generally, the case of the capacitor has a cylindrical shape. Patent Document 1 discloses an example of an inverter unit including a cylindrical capacitor.

[0003] The inverter unit disclosed in Patent Document 1 includes a partition plate (housing base) that divides the inside into a main body part in which a plurality of switching elements are arranged and a wind tunnel part through which cooling air passes. A through hole through which a capacitor cover penetrates is formed in the housing base. The capacitor cover has a bottomed cylindrical shape and is formed of an elastic silicon rubber material. The capacitor is housed in the capacitor cover in a state of being fitted into a capacitor band and an annular sheet metal. The capacitor cover has a flange portion. The flange portion is fixed to the main body part side of the housing base together with the capacitor band and the annular sheet metal by fixing screws, so that the capacitor is fixed to the housing base in a state of penetrating the through hole together with the capacitor cover.

[0004] In the prior art disclosed in Patent Document 1, the capacitor is restrained around the case by a capacitor band, and in that state, it is fixed to the housing base together with the annular sheet metal and the flange portion of the capacitor cover. According to such a fixing method, the gap of the through hole formed in the housing base may be sealed by the flange portion of the capacitor cover, and the intrusion of dust from the wind tunnel part to the main body part may be prevented. However, on the other hand, the restraint of the case by the capacitor band and the annular sheet metal causes stress on the case when the capacitor thermally expands during energization. The stress generated in the case may lead to damage of the case.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2012-227252 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] This disclosure has been made in view of the above-mentioned problems. One object of this disclosure is to provide a technology that can seal the gap in a partition plate without generating stress in the case when the case housing the capacitor penetrates the partition plate that divides the inside of the inverter unit. [Means for solving the problem]

[0007] An inverter unit of a power converter according to one embodiment of the present disclosure is The capacitor is housed inside. Cylindrical capacitor cable S and The inverter unit includes a partition plate that separates the inside from the outside and has a round hole through which the capacitor case passes. The inverter unit also includes a gasket that fills the gap between the edge of the round hole in the partition plate and the capacitor case as it passes through the hole. The gasket has an annular base that sandwiches its edge from the front and back when installed in the round hole, and a membrane that extends from the base toward the center of the round hole and adheres tightly to the circumferential surface of the capacitor case. A groove is formed on the outside of the ring of the base into which the edge is inserted, and the membrane is provided on the base such that the groove and the membrane are on the same plane. ru.

[0008] The inverter unit described above may further include a stud provided at the bottom of the capacitor case and a support plate to which the stud is fixed. The inverter unit may also further include one or more switching elements and a laminated conductor that connects the one or more switching elements and the terminals of the capacitor in the same plane. [Effects of the Invention]

[0011] According to the inverter unit described above, the gap between the capacitor case and the circular hole in the partition plate is sealed by a gasket. Since the membrane of the gasket is flexible, it can maintain close contact with the circumferential surface of the capacitor case even when the capacitor case expands due to heat, preventing dust from entering the inverter unit from the outside. In addition, the bending of the membrane in response to the thermal expansion of the capacitor case prevents stress from being generated in the capacitor case. [Brief explanation of the drawing]

[0013] [Figure 1] This is a perspective view of an inverter unit according to an embodiment of the present disclosure. [Figure 2] Figure 1 is a perspective view of the inverter unit with the cover and laminate busbar removed. [Figure 3] Figure 1 is a rear view of the inverter unit. [Figure 4] Figure 1 is a side view of the inverter unit. [Figure 5] Figure 4 shows a cross-sectional view of the inverter unit AA. [Figure 6] Figure 5 is a detailed view of section C of the inverter unit. [Figure 7] This is a detailed view of section B of the inverter unit shown in Figure 4. [Figure 8] This figure shows the state in which the packing for the inverter unit according to the embodiment of this disclosure is attached to the inverter unit. [Figure 9] This is a cross-sectional view showing an example of a specific shape of a packing for an inverter unit according to an embodiment of the present disclosure. [Figure 10] Figure 9 is a cross-sectional view showing the inverter unit packing installed in the circular hole of the partition plate. [Figure 11] Figure 9 is a cross-sectional view showing the sealing state of the gap between the round hole in the partition plate and the capacitor case by the gasket for the inverter unit. [Figure 12]It is a cross-sectional view showing another example of the specific shape of the packing for an inverter unit according to an embodiment of the present disclosure. [Figure 13] It is a cross-sectional view of the state where the packing for the inverter unit shown in FIG. 12 is attached to the round hole of the partition plate.

Mode for Carrying Out the Invention

[0014] Hereinafter, an inverter unit according to an embodiment of the present disclosure and the packing used therefor will be described with reference to the drawings.

[0015] 1. Inverter Unit FIG. 1 is a perspective view of an inverter unit according to the present embodiment. The inverter unit 10 houses a plurality of capacitor cases 40 inside a housing 11. The capacitor case 40 is a cylindrical aluminum case, and the main body of the capacitor is housed inside.

[0016] The inside of the inverter unit 10 is partitioned into a circuit chamber 101 and a wind tunnel chamber 102 by a partition plate 30. The circuit chamber 101 is a space from the partition plate 30 to the cover 14. In order to prevent the intrusion of dust from the outside, the circuit chamber 101 is sealed by a lid (not shown). Although hidden by the cover 14 and not shown in FIG. 1, switching elements and a substrate unit, which are the main body parts of the inverter unit 10, are arranged in the circuit chamber 101. Also, the terminals 42 and 43 of the capacitor are arranged in the circuit chamber 101. The terminals 42 and 43 of the capacitor are connected to the terminals 42 and 43 of the capacitor at the same potential by a laminated conductor laminated bus bar 22, and further connected to one or more switching elements in the same plane.

[0017] The wind tunnel chamber 102 is a space communicating with the outside. With the partition plate 30 as a boundary, the wind tunnel chamber

[0018] FIG. 2 is a perspective view of the inverter unit 10 with the cover 14 and the laminated bus bar 22 shown in FIG. 1 removed. On the floor 33 connected by the partition plate 30 and the step 32, a plurality of switching elements 23 composed of semiconductor elements such as IGBTs are arranged side by side. The capacitor case 40 is arranged such that the terminals 42 and 43 provided on its top surface are located on substantially the same plane as the switching element 23. In the circuit chamber 101, floors 33 and 34 having a two-layer structure including the floor 33 on which the switching element 23 is arranged are provided. A substrate unit 24 is installed on the upper floor 34.

[0019] The capacitor cases 40 are arranged side by side in two rows. Each capacitor case 40 penetrates the partition plate 30. The partition plate 30 is a panel made of metal or hard resin. A round hole 31 for penetrating the capacitor case 40 is formed in the partition plate 30. Although the space between the round hole 31 and the capacitor case 40 is sealed, the structure for this sealing will be described in detail later. A stud that is not shown in FIG. 1 is provided on the bottom surface of the capacitor case 40. The stud is fixed to a support plate 50 provided in the wind tunnel chamber 102. The partition plate 30 and the support plate 50 are fixed by a frame 12.

[0020] The above is the outline of the configuration of the inverter unit 10. The detailed configuration of the inverter unit 10 is shown in the rear view, side view, and cross-sectional view.

[0021] FIG. 3 is a rear view of the inverter unit 10. As shown in the rear view, another frame 13 is provided behind the frame 12 provided at the entrance of the wind tunnel chamber 102. This frame 13 is located near the center of the wind tunnel chamber 102. The support plate 50 is fixed to both sides of these two frames 12 and 13. As described above, the stud 41 of the capacitor case 40 is fixed to the support plate 50. Further, a heat dissipation fin 21 is provided in the space deeper than the frame 13 of the wind tunnel chamber 102.

[0022] Figure 4 is a side view of the inverter unit 10 from the circuit chamber 101 side. In this side view, the cover 14, circuit board unit 24, floor 34, and laminate busbar 22 shown in Figure 1 have been removed. The partition plate 30 through which the capacitor case 40 passes and the floor 33 on which the switching elements 23 are located are connected by a step 32. Heat dissipation fins 21 (see Figure 3) are attached to the back of the floor 33, specifically to the back of the switching elements 23. In addition, multiple exhaust fans 15 are attached to the front of the inverter unit 10 (the right side in Figure 4). The exhaust fans 15 expel the hot air inside the wind tunnel chamber 102, which has been heated by the heat dissipation from the heat dissipation fins 21, to the outside.

[0023] Figure 5 is a cross-sectional view AA of the inverter unit 10 shown in Figure 4. As shown in the cross-sectional view, the capacitor case 40 penetrates the partition plate 30 and is sandwiched at both ends between the support plate 50 and the laminate busbar 22.

[0024] Figure 6 is a detailed view of section C of the inverter unit 10 shown in Figure 5. As shown in the detailed view of section C, the bottom surface of the capacitor case 40 is in contact with the support plate 50. Studs 41 provided on the bottom surface of the capacitor case 40 pass through the support plate 50 and are fastened to bolts 51. The top surface of the capacitor case 40 is in contact with the laminate busbar 22. Terminals 42 and 43 provided on the top surface of the capacitor case 40 are fixed to the laminate busbar 22. As a result, the capacitor case 40 is positioned by being restrained at both ends by the laminate busbar 22 and the support plate 50. On the other hand, a gap is provided between the capacitor case 40 and the partition plate 30, and the partition plate 30 does not directly restrain the capacitor case 40.

[0025] Figure 7 is a detailed view of section B of the inverter unit 10 shown in Figure 4. As shown in the detailed view of section B, a round hole 31 is formed in the partition plate 30. The capacitor case 40 passes through the round hole 31. The diameter of the capacitor case 40 used in the inverter unit 10 is always smaller than the diameter of the round hole 31. Therefore, a gap is always created between the circumferential surface 44 of the capacitor case 40 and the edge 31a of the round hole 31. To prevent dust from entering through this gap, the inverter unit 10 is provided with a packing, which is described below.

[0026] 2. Gasket for inverter unit Figure 8 shows the state in which the inverter unit packing according to this embodiment is attached to the inverter unit 10. In the example shown in Figure 8, four circular holes 31 are formed in the partition plate 30. The inverter unit packing is not attached to the upper right circular hole 31. When the capacitor case 40 is placed in the circular hole 31 where the inverter unit packing is not attached, a gap is created between the peripheral surface 44 of the capacitor case 40 and the edge 31a of the circular hole 31, as shown in the lower right.

[0027] An inverter unit packing 60 is installed in the upper left circular hole 31. The inverter unit packing 60 is arranged in a continuous annular shape along the edge 31a of the circular hole 31. When the capacitor case 40 is placed in the circular hole 31 with the inverter unit packing 60 installed, the gap between the circumferential surface 44 of the capacitor case 40 and the edge 31a of the circular hole 31 is filled by the inverter unit packing 60, as shown in the lower left. As the material for the inverter unit packing 60, a material having insulating properties, heat resistance, weather resistance, flame retardancy, and flexibility is used, such as ethylene propylene rubber (EPDM rubber) or chloroprene rubber (CR rubber).

[0028] Figure 9 is a cross-sectional view showing an example of the specific shape of the inverter unit packing 60. The inverter unit packing 60 comprises a base 61 and a membrane 62. The base 61 is an annular, endless strip. The membrane 62 is provided inside the annulus of the base 61. The membrane 62 and the base 61 are integrally molded. A groove 63 is formed on the outside of the annulus of the base 61. In the example shown in Figure 9, the membrane 62 is provided on the base 61 such that the membrane 62 and the groove 63 are located on the same plane.

[0029] Figure 10 is a cross-sectional view of the inverter unit packing 60 installed in the round hole 31 of the partition plate 30. When the inverter unit packing 60 is installed in the round hole 31, the edge 31a of the round hole 31 is inserted into the groove 63 of the base 61. The base 61 is manufactured so that the width of the groove 63 is smaller than the thickness of the partition plate 30. Therefore, the edge 31a of the round hole 31 inserted into the groove 63 of the base 61 is sandwiched between the front and back sides of the base 61. The base 61 is also manufactured to a size that allows the edge 31a of the round hole 31 to contact the back of the groove 63. When the inverter unit packing 60 is installed in the round hole 31, the membrane 62 extends from the base 61 toward the center of the round hole 31.

[0030] Figure 11 is a cross-sectional view showing the sealing state of the gap between the round hole 31 of the partition plate 30 and the capacitor case 40 by the inverter unit packing 60. The round hole 31 of the inverter unit packing 60 is manufactured so that the inner diameter of the membrane 62 is smaller than the outer diameter of the capacitor case 40. Therefore, when the capacitor case 40 is inserted into the round hole 31 with the inverter unit packing 60 installed, the membrane 62 extending from the base 61 toward the center of the round hole 31 adheres tightly to the circumferential surface 44 of the capacitor case 40.

[0031] As shown in Figure 11, the membrane 62 adheres tightly to the circumferential surface 44 of the capacitor case 40, thereby sealing the gap between the capacitor case 40 and the round hole 31 of the partition plate 30. Since the membrane 62 is flexible, it maintains its tight contact with the circumferential surface 44 of the capacitor case 40 even when the capacitor case 40 expands due to thermal expansion during energization. This prevents dust from entering the circuit chamber 101 (inside) from the wind tunnel chamber 102 (outside). In addition, the bending of the membrane 62 in response to the thermal expansion of the capacitor case 40 prevents stress from being generated in the capacitor case 40, thus reducing the risk of damage to the capacitor case 40.

[0032] 3. Variant Instead of the inverter unit packing 60, an inverter unit packing 70 having the shape shown in Figure 12 may be used. The inverter unit packing 70 comprises an integrally molded base 71 and a membrane 72. In the inverter unit packing 70, the upper surface of the base 71 and the upper surface of the membrane 72 are connected flat. In other words, the inverter unit packing 70 has a flat upper surface without any steps. The groove 73 of the base 71 is formed on a plane offset from the plane on which the membrane 72 is located.

[0033] Figure 13 is a cross-sectional view showing the inverter unit packing 70 installed in the round hole 31 of the partition plate 30. The edge 31a of the round hole 31 is inserted into the groove 73 of the base 71, and the edge 31a of the round hole 31 is sandwiched from both sides by the base 71. When the inverter unit packing 70 is installed in the round hole 31, the membrane 72 extends from the base 71 toward the center of the round hole 31.

[0034] The inverter unit packing used in the above embodiment is an annular, endless strip, but an inverter unit packing made of a flexible material with an end can also be used. For example, an arc-shaped or linear inverter unit packing having the cross-sectional shape shown in Figure 9 or Figure 12 can be used. If it is a strip made of a flexible material, it can be bent along the round hole 31 and fitted into the edge 31a of the round hole 31. Furthermore, by cutting the end as appropriate to adjust the length, it can be used for round holes 31 of various sizes. [Explanation of symbols]

[0035] 10 Inverter Units 22 Laminated busbars (laminated conductors) 23 Switching elements 30 partition plates 31 round holes 31a Edge 40 Capacitor Case 41 studs Terminals 42 and 43 50 Support plate 60, 70 Inverter unit packing 61, 71 base 62, 72 membranes 63, 73 groove 101 Circuit room 102 Wind tunnel chamber

Claims

1. An inverter unit for a power converter, A cylindrical capacitor case that houses the capacitor inside, A partition plate separates the inside and outside of the inverter unit, and has a round hole through which the capacitor case passes; The partition plate comprises a packing that fills the gap between the edge of the round hole and the capacitor case, which penetrates the round hole. The aforementioned packing is A ring-shaped base that clamps the edge from the front and back sides when attached to the aforementioned round hole, The capacitor case comprises a membrane extending from the base toward the center of the round hole and in close contact with the circumferential surface of the capacitor case, An inverter unit characterized in that a groove is formed on the outside of the annular base into which the edge is inserted, and the membrane is provided on the base such that the groove and the membrane are located on the same plane.

2. In the inverter unit according to claim 1, A stud provided at the bottom of the aforementioned capacitor case, The system further comprises a support plate to which the stud is fixed. An inverter unit characterized by the following features.

3. In the inverter unit according to claim 1, One or more switching elements, The system further comprises a laminated conductor connecting one or more switching elements and the terminals of the capacitor in the same plane. An inverter unit characterized by the following features.

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