Film capacitors, coupled capacitors, inverters and electric vehicles

Abstract

This film capacitor includes: a film laminate made by laminating dielectric films so that every other dielectric film is inverted; and a first metal electrode and a second metal electrode that are respectively located on a pair of end surfaces of the film laminate. A metal layer has a connecting metal layer that connects a common metal layer to a strip-shaped metal layer. A first connecting wiring extends in a first direction from the common metal layer. A second connecting wiring extends in a second direction from the first connecting wiring. A third connecting wiring extends in the first direction from the second connecting wiring and is directly connected to the strip metal layer. The end of the second connecting wiring connected to the third connecting wiring is located more outward, in the second direction, than a first lateral edge of the strip metal layer.

Description

[Technical field]

[0001] The present disclosure relates to a film capacitor, a coupled capacitor, an inverter, and an electric vehicle. [Background technology]

[0002] An example of the prior art is described in Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5984097 Summary of the Invention

[0004] The film capacitor of the present disclosure includes a rectangular film laminate having a metal layer disposed on one surface, and a plurality of dielectric films laminated on a first edge of the first direction of the first surface, the dielectric films having a continuous edge insulating region along a second direction perpendicular to the first direction, wherein the film laminate is formed of dielectric films in a first state and dielectric films in a second state whose orientations are inverted relative to each other so that the planar positions of the edge insulating regions overlap every other film, and a first metal electrode and a second metal electrode located on each of a pair of end faces of the film laminate in the first direction and electrically connected to the metal layer. The metal layer electrically connected to the first metal electrode has a common metal layer extending in the second direction at a second edge portion of the one surface in the first direction, a plurality of strip-shaped metal layers extending in the first direction and electrically connected to the common metal layer, and a connection metal layer connecting the common metal layer and the strip-shaped metal layer, and the connection metal layer includes a first connection wiring directly connected to the common metal layer and extending from the common metal layer in the first direction, a second connection wiring directly connected to the first connection wiring and extending from the first connection wiring in the second direction, and a third connection wiring directly connected to the second connection wiring, extending from the second connection wiring in the first direction and directly connected to the strip-shaped metal layer. The end of the second connection wiring connected to the third connection wiring is located outside the first side edge of the strip-shaped metal layer in the second direction, and the connection metal layer of the dielectric film in the first state and the connection metal layer of the dielectric film in the second state are arranged in point symmetry with respect to the center of the one surface.

[0005] The film capacitor of the present disclosure includes a rectangular parallelepiped film laminate having a first dielectric film having a first metal layer disposed on one surface thereof, the first metal layer having a first common metal layer located continuously at a first edge of the first direction of the first surface along a second direction perpendicular to the first direction, and a second common metal layer located continuously at a second edge of the first direction of the first surface along the second direction, the second common metal layer being located continuously along the second direction, the second edge of the first direction of the first surface having a second metal layer disposed on one surface thereof, the second dielectric film having an edge insulating region located continuously along the second direction perpendicular to the first direction, the second dielectric film being disposed on one surface thereof, the second dielectric film having an edge insulating region located continuously at a first edge and a second edge of the first direction of the first surface along the second direction perpendicular to the first direction, the film laminate being laminated such that a portion of the first metal layer and a portion of the second metal layer overlap in a planar view, and a first metal electrode and a second metal electrode located on each of a pair of end surfaces of the film laminate in the first direction, the first metal electrode and the second metal electrode being electrically connected to the first metal layer. The first metal layer includes a plurality of first strip-shaped metal layers extending in the first direction and electrically connected to the first common metal layer, a plurality of second strip-shaped metal layers extending in the first direction and electrically connected to the second common metal layer, a first connection metal layer connecting the first common metal layer and the first strip-shaped metal layer, and a second connection metal layer connecting the second common metal layer and the second strip-shaped metal layer. The second metal layer is a planar metal layer electrically insulated from the first metal electrode and the second metal electrode by the edge insulating region. The first connection metal layer includes a first connection wiring directly connected to the first common metal layer and extending from the first common metal layer in the first direction, a second connection wiring directly connected to the first connection wiring and extending from the first connection wiring in the second direction, and a third connection wiring directly connected to the second connection wiring, extending from the second connection wiring in the first direction and directly connected to the first strip-shaped metal layer. The second connection metal layer includes a fourth connection wiring that is directly connected to the second common metal layer and extends from the second common metal layer in the first direction, a fifth connection wiring that is directly connected to the fourth connection wiring and extends from the fourth connection wiring in the second direction, and a sixth connection wiring that is directly connected to the fifth connection wiring, extends from the fifth connection wiring in the first direction, and is directly connected to the second strip-shaped metal layer.The end of the second connection wiring connected to the third connection wiring is located outside the first side edge of the first strip-shaped metal layer in the second direction, and the end of the fifth connection wiring connected to the sixth connection wiring is located outside the first side edge of the second strip-shaped metal layer in the second direction, and the first connection metal layer and the second connection metal layer are arranged in point symmetry with the center of the one surface of the first dielectric film as the point of symmetry.

[0006] In the linked capacitor of the present disclosure, a plurality of film capacitors, including the above-described film capacitor, are connected by a bus bar.

[0007] The inverter of the present disclosure includes a bridge circuit configured with switching elements, and a capacitive section connected to the bridge circuit and including the above-mentioned film capacitor.

[0008] The electric vehicle of the present disclosure includes a power source, the above-mentioned inverter connected to the power source, a motor connected to the inverter, and wheels driven by the motor. [Brief description of the drawings]

[0009] [Figure 1A] FIG. 1 is a diagram illustrating a configuration of a film capacitor according to a first embodiment, and is a plan view of a dielectric film. [Figure 1B] FIG. 1 is a diagram illustrating a configuration of a film capacitor according to a first embodiment, and is a schematic cross-sectional view illustrating a laminated state of a film. [Figure 1C] FIG. 1 is a diagram illustrating a configuration of a film capacitor according to a first embodiment, and is a plan view of the film capacitor viewed from above. [Diagram 2] FIG. 2 is an enlarged plan view of the vicinity of a connecting metal layer of the dielectric film. [Diagram 3] 2 is an exploded enlarged perspective view showing a laminated state of a dielectric film in a first state and a film in a second state. FIG. [Figure 4] FIG. 2 is an exploded perspective view showing a laminated state of the dielectric film (before cutting). [Diagram 5]FIG. 4 is an external perspective view showing the configuration of the film laminate after cutting. [Figure 6] FIG. 2 is an external perspective view showing the configuration of the metal electrode after thermal spraying. [Figure 7A] 13 is an enlarged plan view of the vicinity of a connecting metal layer of a dielectric film in a second embodiment. FIG. [Figure 7B] 13 is an enlarged plan view of the vicinity of a connecting metal layer of a dielectric film in a second embodiment. FIG. [Figure 8] 13 is an enlarged plan view of the vicinity of a connecting metal layer of a dielectric film in a third embodiment. FIG. [Figure 9] 13 is an enlarged plan view of the vicinity of a connecting metal layer of a dielectric film in a fourth embodiment. FIG. [Figure 10A] FIG. 13 is a diagram showing a configuration of a film capacitor according to a fifth embodiment, and is a plan view of a dielectric film. [Figure 10B] FIG. 13 is a diagram showing a configuration of a film capacitor according to a fifth embodiment, and is a plan view of a dielectric film. [Figure 10C] FIG. 13 is a diagram illustrating the configuration of a film capacitor according to a fifth embodiment, and is a schematic cross-sectional view illustrating the laminated state of the film. [Figure 11] 3 is an enlarged plan view of the vicinity of a first connecting metal layer and a second connecting metal layer. FIG. [Figure 12A] FIG. 13 is a diagram showing the configuration of a film capacitor according to a sixth embodiment, and is a plan view of a dielectric film. [Figure 12B] FIG. 13 is a diagram showing the configuration of a film capacitor according to a sixth embodiment, and is a plan view of a dielectric film. [Figure 12C] FIG. 13 is a diagram illustrating the configuration of a film capacitor according to a sixth embodiment, and is a schematic cross-sectional view illustrating the laminated state of the film. [Figure 13] FIG. 13 is an external perspective view showing a modified example of the film capacitor. [Figure 14] FIG. 1 is a perspective view showing a schematic configuration of a coupled capacitor. [Figure 15] FIG. 2 is a schematic diagram for explaining the configuration of an inverter. [Figure 16] FIG. 1 is a schematic diagram for explaining the configuration of an electric vehicle. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The objects, features and advantages of the present disclosure will become more apparent from the following detailed description and drawings.

[0011] The film capacitor of the basic configuration of the present disclosure is constructed by winding or stacking multiple metallized films in one direction, the metal films being formed by vapor-depositing a metal film that serves as an electrode on the surface of a dielectric film containing, for example, polypropylene resin.

[0012] Among these, in the case of a laminated film capacitor, when a laminate of metallized films is cut to a required size, the metal film is also cut, and the metal film is exposed at the cut surface. When a voltage is applied to the exposed metal film during use of the film capacitor, a discharge occurs at the cut surface.

[0013] Patent document 1 proposes a configuration in which, in a metallized film constituting a film capacitor, part of an exposed portion (gap strip) of the film surface that is groove-shaped or band-shaped of a certain width and does not have a metal film, called an insulating margin, has a bent portion that is oblique to the parallel direction in which each insulating margin extends, thereby insulating the exposed metal film at the cut surface of a laminate in which the metallized film is stacked.

[0014] However, although the laminated film capacitor described in Patent Document 1 may reduce discharge at the cut surfaces, there is a problem in that there is a large loss of capacitance in the vicinity of the cut surfaces in the film laminate.

[0015] An object of the present disclosure is to provide a stacked film capacitor, a linked capacitor, an inverter, and an electric vehicle that reduce discharge at end faces and have little capacitance loss.

[0016] Hereinafter, a film capacitor according to a first embodiment of the present disclosure will be described with reference to the drawings. A film capacitor 10 according to this embodiment is configured by alternately laminating a plurality of dielectric films 1 or 2 each having a metal layer 3 on one surface of a base film, as shown in FIG. 1A.

[0017] In this embodiment, the metal layer 3 is a so-called comb-tooth shaped metal layer and includes a plurality of strip-shaped metal layers 3a, a plurality of connecting metal layers 3b, and one common metal layer 3c, and the strip-shaped metal layers 3a are each electrically connected to the common metal layer 3c via the connecting metal layers 3b.

[0018] Each strip-shaped metal layer 3a will become an internal electrode of the capacitor after lamination. The dielectric films 1 and 2 have the same structure except that their orientations when laminated are reversed, but to indicate their orientations after lamination, the strip-shaped metal layers 3a are labeled 1A-1L or 2A-2L in order from the end as shown in Figures 1A and 1C. The dielectric films 1 and 2, whose orientations are reversed from each other, are the dielectric films in a first state and the dielectric films in a second state, respectively.

[0019] In each figure, the direction in which the strip-shaped metal layers 3a positioned parallel to each other extend is called the first direction, and the direction in which the parallel strip-shaped metal layers 3a are arranged is called the second direction. The film is laminated in a third direction (z direction in the figure) perpendicular to the first and second directions. The first direction may be called the x direction, the second direction may be called the y direction, and the third direction may be called the z direction. Details of the film laminate 4 after lamination will be described later.

[0020] Each strip-shaped metal layer 3a on the surface of the dielectric films 1, 2 is formed by metal deposition on a base film. Each strip-shaped metal layer 3a extends linearly along the first direction. Between adjacent strip-shaped metal layers 3a in the y direction, a film surface (hereinafter, insulating margin S) is exposed, so that each strip-shaped metal layer 3a is electrically insulated from the other. Each insulating margin S is connected to an edge insulating region T that continues in the second direction (y direction) at a first end side in the first direction (x direction). The interval (pitch P) between each insulating margin S is the sum of the width P1 of each strip-shaped metal layer 3a in the y direction and the width P2 of each insulating margin S in the y direction (P=P1+P2).

[0021] The common metal layer 3c extends in the second direction on the side opposite the edge insulating region T of the dielectric films 1 and 2, i.e., on the second edge in the first direction. Although the strip-shaped metal layers 3a are electrically insulated from each other by the insulating margins S, the metal layers 3 are electrically connected as a whole by being connected to one common metal layer 3c.

[0022] The connection metal layer 3b connects the strip metal layer 3a and the common metal layer 3c, and functions as a fuse for each strip metal layer 3a. For example, if a strip metal layer 3a is short-circuited with another strip metal layer 3a due to dielectric breakdown of the base film, causing a current greater than a specified level to flow, the connection metal layer 3b burns out to break the connection, preventing the entire film capacitor 10 from stopping functioning.

[0023] As shown in the enlarged plan view of the vicinity of the connection metal layer in FIG. 2, the connection metal layer 3b includes a first connection wiring 3b1, a second connection wiring 3b2, and a third connection wiring 3b3. The first connection wiring 3b1 is directly connected to the common metal layer 3c and extends from the common metal layer 3c in a first direction. The second connection wiring 3b2 is directly connected to the first connection wiring 3b1 and extends from the first connection wiring 3b1 in a second direction. The third connection wiring 3b3 is directly connected to the second connection wiring 3b2 and extends from the second connection wiring 3b2 in the first direction to directly connect to the strip-shaped metal layer 3a. In this embodiment, the first connection wiring 3b1, the second connection wiring 3b2, and the third connection wiring 3b3 all have a linear shape. Here, "extending in the first direction" refers to a case where the first direction component of the extension direction is larger than the second direction component. Similarly, "extending in the second direction" means that the second directional component of the extending direction is larger than the first directional component. The connecting metal layer 3b having such a configuration has a higher electrical resistance than the strip-shaped metal layer 3a, and functions as a fuse.

[0024] In the connection metal layer 3b of this embodiment, the first connection wiring 3b1 and the third connection wiring 3b3 extend in parallel in the first direction, and the second connection wiring 3b2 extends in parallel in the second direction. The end of the second connection wiring 3b2 connected to the third connection wiring 3b3 is located outside the first side 3a1 of the strip-shaped metal layer 3a in the second direction. The third connection wiring 3b3 extends from the second connection wiring 3b2 in the first direction and directly connects to the first side 3a1 of the strip-shaped metal layer 3a, for example. In addition, the end of the second connection wiring 3b2 connected to the first connection wiring 3b1 may be located at the same position as the second side 3a2 of the strip-shaped metal layer 3a in the second direction, or may be located inside the second side 3a2. In this embodiment, one end of the second connection wiring 3b2 is located outside the first side 3a1, the other end of the second connection wiring 3b2 is located at the same position as the second side 3a2, and the length L of the second connection wiring 3b2 in the second direction is greater than the width W of the strip-shaped metal layer 3a. The length L in the second direction is the projection length of the second connection wiring 3b2 in the second direction.

[0025] 3, the connecting metal layer 3b of the dielectric film 1 in a first state and the connecting metal layer 3b of the dielectric film 2 in a second state whose orientation is reversed from that of the first state are disposed in point symmetry with respect to the center of one surface of the base film. That is, when the film laminate 4 is viewed in the z direction, if the connecting metal layer 3b of the dielectric film 1 is rotated 180° around the symmetric point, it will have the same shape as the connecting metal layer 3b of the dielectric film 2.

[0026] When the film capacitor 10 is manufactured, the film laminate 4 is obtained, for example, by cutting a long laminate. The cutting line is parallel to the first direction (x direction), but is not necessarily always at the same position in the width direction of the strip-shaped metal layer 3a. The cut strip-shaped metal layer 3a is exposed at the end face of the film capacitor 10 in the second direction (y direction). If the strip-shaped metal layer 3a is in a conductive state with the common metal layer 3c even after cutting, a voltage is applied to the strip-shaped metal layer 3a during use, causing discharge at the end face. When the strip-shaped metal layer 3a and the common metal layer 3c are connected by the connection metal layer 3b as in this embodiment, at least one of the second connection wiring 3b2 of the dielectric film 1 and the second connection wiring 3b2 of the dielectric film 2 crosses the cutting line regardless of the position of the cutting line, so that one or both of the second connection wirings 3b2 are cut, and the strip-shaped metal layer 3a and the common metal layer 3c are electrically insulated. This makes it possible to reduce discharge at the end face of the film capacitor 10. Furthermore, since the strip-shaped metal layer 3a that is electrically insulated from the common metal layer 3c is only the cut strip-shaped metal layer 3a, the film capacitor 10 can have a small loss of capacitance.

[0027] Examples of materials constituting the base film of the dielectric films 1 and 2 include organic resin materials such as polypropylene, polyethylene terephthalate, polyarylate, and cycloolefin polymer.

[0028] 1B, the dielectric films 1, 2 are stacked such that the orientations of the dielectric film 1 and the dielectric film 2 adjacent thereto in the vertical direction in the figure are alternately reversed by 180° in the x direction, i.e., the dielectric films 1, 2 are stacked such that the positions of the edge insulating regions T at one end of each of the dielectric films 1, 2 are alternately reversed in the x direction to form a film laminate 4. Similarly, the dielectric films 1, 2 are stacked such that the positions of the common metal layers 3c at the other end of each of the dielectric films 1, 2 are alternately reversed in the x direction.

[0029] Metal electrodes (hereinafter, metallicons) are located on both end faces in the x direction of the film laminate 4 by metal spraying. One of the metallicons located at both ends in the x direction is called metallicons 5A (first metal electrode) and the other is called metallicons 5B (second metal electrode), but they only differ in their locations and have no difference in structure. For example, the metallicons 5A are electrically connected to the common metal layer 3c of the dielectric film 1, and are also electrically connected to each strip-shaped metal layer 3a through the common metal layer 3c. The metal layer 3 of the dielectric film 1 and the metallicons 5B are electrically insulated by the edge insulating region T. On the other hand, the metallicons 5B are electrically connected to the common metal layer 3c of the dielectric film 2, and are also electrically connected to each strip-shaped metal layer 3a through the common metal layer 3c. The metal layer 3 of the dielectric film 2 and the metallicons 5A are also electrically insulated by the edge insulating region T.

[0030] 4 to 6 are diagrams for explaining the process of manufacturing a film capacitor. In Fig. 4 to 6, similarly to Fig. 1A to Fig. 1C, the extending direction of the parallel strip-shaped metal layers 3a is defined as a first direction (x direction in the figure), the extending direction of the common metal layer 3c (y direction perpendicular to the x direction) is defined as a second direction, and the lamination direction of the film perpendicular to the first and second directions is defined as a third direction (z direction).

[0031] In producing the laminated film capacitor 10, first, as shown in Figure 4, multiple dielectric films 1 and dielectric films 2 each having multiple strip-shaped metal layers 3a continuous along the x direction and a common metal layer 3c extending in the y direction on the surface of the film are stacked with their orientations in the x direction alternately reversed, i.e., the orientation in the x direction of each film is reversed 180° so that the planar positions of the edge insulating regions T overlap every other film.

[0032] As described above, in this embodiment, the dielectric film 1 and the dielectric film 2 are the same in configuration, but the orientation in the x direction is simply reversed. However, the configuration of the dielectric film 1 and the dielectric film 2 may be different. For example, the dielectric film 1 may be configured such that the third connection wiring 3b3 is connected to the side edge on the +y side of the strip-shaped metal layer 3a, and the dielectric film 2 may be configured such that the third connection wiring 3b3 is connected to the side edge on the +y side of the strip-shaped metal layer 3a, in a state where the dielectric film 1 and the dielectric film 2 are laminated so that the planar positions of the edge insulating regions T overlap every other film. That is, the dielectric film 1 and the dielectric film 2 are different in that the connection metal layer 3b is line-symmetrical with respect to the x direction, and the other configurations may be the same. In addition, the lamination method can be a conventionally known method, such as stacking the long dielectric films 1 and 2 and winding them around a cylinder or a tube with a polygonal cross section. The virtual line (two-dot chain line) in FIG. 4 indicates the cutting line after winding around a tube or the like.

[0033] Fig. 5 is a view of the film laminate 4 after being cut to a predetermined length, viewed from the cut surface (y-direction end surface). As shown in Fig. 5, the vertically adjacent dielectric films 1 and 2 are laminated in a state in which they are slightly shifted (offset) in the x direction, so that the common metal layer 3c is exposed at both end surfaces in the x direction of the film laminate 4. As shown in Fig. 5, the strip-shaped metal layer 3a exposed at the cut surface of the film laminate 4 is not connected to the common metal layer 3c because the second connection wiring 3b2 has been cut, and is electrically insulated from the common metal layer 3c.

[0034] In addition, an insulating layer 12 serving as a protective layer for the film laminate 4, such as a base film not having a metal layer 3, may be laminated on the upper surface of the film laminate 4 in the embodiment. The insulating layer 12 may be omitted.

[0035] 6, a first metal electrode and a second metal electrode (metallikons 5A, 5B) are formed by metal spraying on both end faces in the x direction of the film laminate 4 where the above-mentioned common metal layer 3c is exposed. As a result, each strip-shaped metal layer 3a on the dielectric films 1, 2 is electrically connected to either the metallikon 5A, 5B via the common metal layer 3c, and functions as an internal electrode of the film capacitor 10.

[0036] The following describes a film capacitor of another embodiment. The other embodiment differs from the first embodiment only in the configuration of the connection metal layer 3b, and the other configurations are the same. Figures 7A and 7B show the connection metal layer 3b of the second embodiment. As shown in Figures 7A and 7B, in the second embodiment, the end of the second connection wiring 3b2 connected to the third connection wiring 3b3 is located outside the first side 3a1 of the strip-shaped metal layer 3a in the second direction.

[0037] The connection metal layer 3b in the first embodiment has a higher electrical resistance value than the strip metal layer 3a and functions as a fuse. The longer the connection metal layer 3b, the higher the energy required for the connection metal layer 3b to break when the strip metal layer 3a is shorted, and a larger current must flow before the connection metal layer 3b will break. In this embodiment, the electrical resistance value of the first connection wiring 3b1 is locally high, so that the first connection wiring 3b1 is more likely to break when the strip metal layer 3a is shorted, improving the fuse function of the connection metal layer 3b. In this embodiment, the width of the second connection wiring 3b2 is larger than the width of the third connection wiring 3b3, so that the third connection wiring 3b3 is more likely to break, improving the fuse function of the connection metal layer 3b. In the example shown in FIG. 7A, the width of the second connection wiring 3b2 is constant. In the example shown in FIG. 7B, the width of the second connection wiring 3b2 is larger in the center than at both ends. That is, the portion connected to the first connection wiring 3b1 and the portion connected to the third connection wiring 3b3 have the same width as the first connection wiring 3b1 and the third connection wiring 3b3, respectively, and the width is larger in the central portion.

[0038] The second connecting wire 3b2 of the second embodiment has a larger wiring width than the second connecting wire 3b2 of the first embodiment. This allows the film capacitor 10 of the second embodiment to have a lower equivalent series resistance (ESR) than the first embodiment. By reducing the ESR, the allowable value of the ripple current of the film capacitor 10 can be increased.

[0039] FIG. 8 shows the connection metal layer 3b of the third embodiment. As shown in FIG. 8, in the third embodiment, the second connection wiring 3b2 has a meandering shape. In the first embodiment, the second connection wiring 3b2 has a straight shape, whereas in the third embodiment, the second connection wiring 3b2 has a meandering shape. In the connection metal layer 3b of the third embodiment, the second connection wiring 3b2 has a meandering shape, thereby ensuring the wiring length of the second connection wiring 3b2. Even if a dielectric breakdown occurs in the dielectric films 1 and 2 and an excessive current flows through the strip-shaped metal layer 3a, the second connection wiring 3b2 is less likely to break, and the operation of the connection metal layer 3b as a fuse can be appropriately suppressed. This can suppress an early decrease in the capacitance of the film capacitor 10 due to excessive fuse operation, which causes the strip-shaped metal layer 3a to be insulated from the common metal layer 3c.

[0040] In each of the above embodiments, the film laminate 4 is formed by laminating the dielectric films 1 and 2 with their orientations in the x direction alternately reversed, and the dielectric films 1 and 2 have the same configuration but different orientations. This is not limiting, and for example, instead of the dielectric film 2, a dielectric film having a metal layer on the entire area of ​​one side of the base film except for the edge insulating area T, that is, a so-called solid patterned dielectric film having a full metal layer, may be used. The metallikon 5A (first metal electrode) is electrically connected to the common metal layer 3c of the dielectric film 1. The metallikon 5B (second metal electrode) is electrically connected to the full metal layer of the dielectric film.

[0041] Fig. 9 shows the connecting metal layer 3b of the fourth embodiment. As shown in Fig. 9, in the fourth embodiment, unlike the first to third embodiments, the end of the second connecting wiring 3b2 continuing to the first connecting wiring 3b1 is positioned outside the second side edge 3a2 of the strip-shaped metal layer 3a in the second direction. This embodiment is the same as the first to third embodiments in that the connecting metal layer 3b of the dielectric film 1 in the first state and the connecting metal layer 3b of the dielectric film 2 in the second state whose orientation is reversed from the first state are arranged in point symmetry with respect to the center of one surface of the base film.

[0042] A film capacitor according to a fifth embodiment of the present disclosure will be described. Figs. 10A to 10C are diagrams showing the configuration of the film capacitor according to the fifth embodiment. Figs. 10A and 10B are plan views of a dielectric film, and Fig. 10C is a schematic cross-sectional view showing a laminated state of the film. A film capacitor 11 according to this embodiment has metallikon 5A and metallikon 5B on both end surfaces of a film laminate 4. The film laminate 4 is formed by alternately laminating a dielectric film (first dielectric film) 1 having a first metal layer 3 on one surface of a base film as shown in Fig. 10A and a dielectric film (second dielectric film) 2 having a second metal layer 8 on one surface of a base film as shown in Fig. 10B. In this embodiment, unlike the first to fourth embodiments described above, the first metal layer 3 of the dielectric film 1 and the second metal layer 8 of the dielectric film 2 have different configurations.

[0043] The first metal layer 3 of the dielectric film 1 includes a first common metal layer 3Ac and a second common metal layer 3Bc, a plurality of first strip-shaped metal layers 3Aa and a plurality of first connecting metal layers 3Ab connected to the first common metal layer 3Ac, and a plurality of second strip-shaped metal layers 3Ba and a plurality of second connecting metal layers 3Bb connected to the second common metal layer 3Bc. The first common metal layer 3Ac and the second common metal layer 3Bc extend in a second direction at a first edge and a second edge in a first direction of the dielectric film 1, respectively. The first common metal layer 3Ac is electrically connected to the metallikon 5A, and the second common metal layer 3Bc is electrically connected to the metallikon 5B. In this embodiment, the film surface is exposed between the first strip-shaped metal layer 3Aa on the metallikon 5A side and the second strip-shaped metal layer 3Ba on the metallikon 5B side, and they are electrically insulated from each other. This exposed film surface forms a central insulating region Tc that is continuous along the second direction at the central portion of the dielectric film 1 in the first direction.

[0044] The first connection metal layer 3Ab includes a first connection wiring 3Ab1 directly connected to the first common metal layer 3Ac and extending from the first common metal layer 3Ac in a first direction, a second connection wiring 3Ab2 directly connected to the first connection wiring 3Ab1 and extending from the first connection wiring 3Ab1 in a second direction, and a third connection wiring 3Ab3 directly connected to the second connection wiring 3Ab2 and extending from the second connection wiring 3Ab2 in the first direction and directly connected to the first strip-shaped metal layer 3Aa. The first connection metal layer 3Ab configured as described above has a higher electrical resistance value than the first strip-shaped metal layer 3Aa and functions as a fuse. The end of the second connection wiring 3Ab2 connected to the third connection wiring 3Ab3 of the first connection metal layer 3Ab is located outside the first side 3a1 of the first strip-shaped metal layer 3Aa in the second direction.

[0045] The second connection metal layer 3Bb includes a fourth connection wiring 3Bb1 directly connected to the second common metal layer 3Bc and extending from the second common metal layer 3Bc in the first direction, a fifth connection wiring 3Bb2 directly connected to the fourth connection wiring 3Bb1 and extending from the fourth connection wiring 3Bb1 in the second direction, and a sixth connection wiring 3Bb3 directly connected to the fifth connection wiring 3Bb2 and extending from the fifth connection wiring 3Bb2 in the first direction and directly connected to the second strip-shaped metal layer 3Ba. The second connection metal layer 3Bb configured as above has a higher electrical resistance value than the second strip-shaped metal layer 3Ba and functions as a fuse. The second connection metal layer 3Bb has an end of the fifth connection wiring 3Bb2 connected to the sixth connection wiring 3Bb3 located outside the first side 3a1 of the second strip-shaped metal layer 3Ba in the second direction.

[0046] 11 is an enlarged plan view of the first connecting metal layer and the vicinity of the second connecting metal layer of the dielectric film 1. As shown in this enlarged plan view, in the dielectric film 1, the first connecting metal layer 3Ab and the second connecting metal layer 3Bb are arranged in point symmetry with respect to the center of one surface of the base film. In other words, when the dielectric film 1 is viewed in plan, if the first connecting metal layer 3Ab of the dielectric film 1 is rotated 180° around the symmetric point, it will have the same shape as the second connecting metal layer 3Bb.

[0047] The second metal layer 8 of the dielectric film 2 is a planar metal layer having a so-called solid pattern. The first edge and the second edge in the first direction of the dielectric film 2 have edge insulating regions T that are continuous in the second direction, and the second metal layer 8 is electrically insulated from the metallikon 5A and the metallikon 5B by the edge insulating regions T.

[0048] The film laminate 4 is laminated such that the first strip-shaped metal layer 3Aa and the second strip-shaped metal layer 3Ba of the first metal layer 3 overlap with the second metal layer 8 in a plan view. The film capacitor 11 of this embodiment including such a film laminate 4 can be a series capacitor in which stacked film capacitors are connected in series by the first metal layer 3 and the second metal layer 8. The film capacitor 11 is a stacked capacitor made of the first common metal layer 3Ac, the first strip-shaped metal layer 3Aa, the first connecting metal layer 3Ab, and the second metal layer 8 on the metallikon 5A side, and a stacked capacitor made of the second common metal layer 3Bc, the second strip-shaped metal layer 3Ba, the second connecting metal layer 3Bb, and the second metal layer 8 on the metallikon 5B side, which are connected in series by the second metal layer 8. The film capacitor 11 of this embodiment can achieve high voltage resistance by being a series capacitor.

[0049] In this embodiment, for example, in plan view, a plurality of first strip-shaped metal layers 3Aa and a plurality of second strip-shaped metal layers 3Ba overlap one second metal layer 8, and the second metal layer 8 does not overlap the first connecting metal layer 3Ab, the first common metal layer 3Ac, the second connecting metal layer 3Bb, or the second common metal layer 3Bc. The second metal layer 8 may include a plurality of planar metal layers, as long as each planar metal layer overlaps the first strip-shaped metal layer 3Aa and the second strip-shaped metal layer 3Ba, respectively, in plan view.

[0050] In the film capacitor 11 of this embodiment, at least one of the second connection wiring 3Ab2 and the fifth connection wiring 3Bb2 of the dielectric film 1 crosses the cutting line no matter where the cutting line is cut in the film laminate 4, so that either or both of the second connection wiring 3Ab2 and the fifth connection wiring 3Bb2 are cut, and at least one of the first strip-shaped metal layer 3Aa and the first common metal layer 3Ac and the second strip-shaped metal layer 3Ba and the second common metal layer 3Bc are electrically insulated. This can reduce discharge at the end faces of the film capacitor 11. Furthermore, the first strip-shaped metal layer 3Aa and the second strip-shaped metal layer 3Ba that are electrically insulated from the first common metal layer 3Ac and the second common metal layer 3Bc are only the cut strip-shaped metal layers, so that the film capacitor 11 has little loss of capacitance.

[0051] A film capacitor according to a sixth embodiment of the present disclosure will be described. FIGS. 12A to 12C are diagrams showing the configuration of the film capacitor according to the sixth embodiment. FIGS. 12A and 12B are plan views of a dielectric film, and FIG. 12C is a schematic cross-sectional view showing a laminated state of the film. The sixth embodiment differs from the fifth embodiment in the configuration of the first metal layer 3 of the dielectric film 1 and the configuration of the second metal layer 8 of the dielectric film 2, but the other configurations are common. In the fifth embodiment, the first connecting metal layer 3Ab and the second connecting metal layer 3Bb are point-symmetric in the dielectric film 1, whereas the first metal layer 3 of this embodiment differs in that the first connecting metal layer 3Ab and the second connecting metal layer 3Bb are line-symmetric with respect to the central insulating region Tc in the dielectric film 1. Furthermore, the second metal layer 8 of the dielectric film 2 includes a plurality of strip-shaped metal layers 8a and a central connecting layer 8b that connects the strip-shaped metal layers 8a to each other at the central portion of the dielectric film 2. The plurality of strip-shaped metal layers 8a of the dielectric film 2 are arranged so as to overlap the first strip-shaped metal layer 3Aa and the second strip-shaped metal layer 3Ba of the dielectric film 1 in a plan view. For example, one strip-shaped metal layer 8a may be arranged for one first strip-shaped metal layer 3Aa, and one strip-shaped metal layer 8a may be arranged for one second strip-shaped metal layer 3Ba. The central connection layer 8b connects, for example, the strip-shaped metal layer 8a corresponding to the first strip-shaped metal layer 3Aa and the strip-shaped metal layer 8a corresponding to the second strip-shaped metal layer 3Ba, and connects the sides of the two strip-shaped metal layers 8a. The central connection layer 8b has a higher electrical resistance than the strip-shaped metal layer 8a and functions as a fuse. The film capacitor 11 of this embodiment can achieve high voltage resistance by forming a series capacitor using the first metal layer 3 and the second metal layer 8 as described above.

[0052] In the film capacitor 11 of this embodiment, the second connection wiring 3Ab2 and the fifth connection wiring 3Bb2 of the dielectric film 1 are cut by the cutting line cut in the film laminate 4. Here, since the first connection metal layer 3Ab and the second connection metal layer 3Bb are symmetrical with respect to the central insulating region Tc, for example, when the third connection wiring 3Ab3 and the sixth connection wiring 3Bb3 are located on the same side and the cutting line passes through the third connection wiring 3Ab3 and the sixth connection wiring 3Bb3, there is a risk that electrical insulation will not be achieved between the first strip-shaped metal layer 3Aa and the first common metal layer 3Ac, and between the second strip-shaped metal layer 3Ba and the second common metal layer 3Bc. Even in such a case, the second metal layer 8 is insulated by cutting between the strip-shaped metal layers 8a connected by the central connection layer 8b, so that discharge at the end faces of the film capacitor 11 can be reduced. Furthermore, since the first strip-shaped metal layer 3Aa and the second strip-shaped metal layer 3Ba, which are electrically insulated from the first common metal layer 3Ac and the second common metal layer 3Bc, are only cut strip-shaped metal layers, a film capacitor 11 with little capacitance loss can be obtained.

[0053] The first connecting metal layer 3Ab and the second connecting metal layer 3Bb in the fifth and sixth embodiments may both have the same configuration as the connecting metal layer 3b in the second to fourth embodiments described above.

[0054] Fig. 13 is an external perspective view showing a modified example of the film capacitor. Film capacitor A is a film capacitor 10 covered with an exterior member 7 from the viewpoints of insulation and environmental resistance. Metallicons 5A and 5B have lead wires 6 for external connection. Fig. 13 shows a state where a part of exterior member 7 has been removed, and the removed part of exterior member 7 is indicated by a dashed line.

[0055] Fig. 14 is a perspective view showing a schematic configuration of a linked capacitor. In Fig. 14, the case and molding resin are omitted in order to make the configuration easier to understand. Linked capacitor B is configured such that a plurality of film capacitors A are connected in parallel by a pair of bus bars 21, 23. Bus bars 21, 23 are configured with terminal portions 21a, 23a and lead-out terminal portions 21b, 23b. Terminal portions 21a, 23a are for external connection, and lead-out terminal portions 21b, 23b are connected to external electrodes 5A, 5B of film capacitor A, respectively.

[0056] FIG. 15 is a schematic diagram for explaining the configuration of an inverter. FIG. 15 shows an example of an inverter C that generates AC from rectified DC. As shown in FIG. 15, the inverter C of this embodiment includes a bridge circuit 31 and a capacitance section 33. The bridge circuit 31 is composed of a switching element such as an IGBT (Insulated Gate Bipolar Transistor) and a diode. The capacitance section 33 is disposed between the input terminals of the bridge circuit 31 and stabilizes the voltage. The inverter C may include the above-mentioned film capacitor 10, A or linked capacitor B as the capacitance section 33.

[0057] The input of the inverter C may be connected to a boost circuit 35 that boosts the voltage of a DC power supply, or may be connected to the DC power supply. On the other hand, the bridge circuit 31 is connected to a motor generator (motor M) that serves as a drive source.

[0058] Fig. 16 is a schematic diagram for explaining the configuration of an electric vehicle. Fig. 16 shows an example of an electric vehicle D, which is a hybrid electric vehicle (HEV).

[0059] An electric vehicle D in FIG. 16 includes a driving motor 41, an engine 43, a transmission 45, an inverter 47, a power source (battery) 49, front wheels 51a and rear wheels 51b.

[0060] This electric vehicle D is equipped with a motor 41 or an engine 43, or both, as a drive source. The output of the drive source is transmitted to a pair of left and right front wheels 51a via a transmission 45. A power source 49 is connected to an inverter 47, and the inverter 47 is connected to the motor 41.

[0061] The electric vehicle D shown in FIG. 16 includes a vehicle ECU 53 and an engine ECU 57. The vehicle ECU 53 performs overall control of the entire electric vehicle D. The engine ECU 57 controls the rotation speed of the engine 43 to drive the electric vehicle D. The electric vehicle D further includes driving devices such as an ignition key 55 operated by a driver, an accelerator pedal (not shown), and a brake. A driving signal corresponding to the operation of the driving device by a driver is input to the vehicle ECU. The vehicle ECU 53 outputs an instruction signal based on the driving signal to the engine ECU 57, the power source 49, and the inverter 47 as a load. In response to the instruction signal, the engine ECU 57 controls the rotation speed of the engine 43 to drive the electric vehicle D. The inverter C to which the film capacitor A, 10 or the linked capacitor B of this embodiment is applied as the capacitance section 33 can be mounted on the electric vehicle D as shown in FIG. 16.

[0062] The inverter C of this embodiment can be applied not only to the above-mentioned hybrid electric vehicle (HEV), but also to various power conversion application products such as electric vehicles (EV), electric bicycles, generators, solar cells, and the like.

[0063] The present disclosure may have the following embodiments.

[0064] The film capacitor of the present disclosure includes a rectangular parallelepiped film laminate having a metal layer disposed on one surface thereof, and a plurality of dielectric films laminated on a first edge of the one surface in a first direction, the dielectric films having edge insulating regions that are continuous along a second direction perpendicular to the first direction, the film laminate including a first state dielectric film and a second state dielectric film whose orientations are inverted such that the planar positions of the edge insulating regions overlap every other film, and a first metal electrode and a second metal electrode located on each of a pair of end surfaces of the film laminate in the first direction and electrically connected to the metal layer, the metal layer electrically connected to the first metal electrode being a common metal layer that is provided on a second edge of the one surface in the first direction and extends in the second direction, and a second metal electrode that extends in the first direction and is connected to the common metal layer. The dielectric film has a plurality of electrically connected strip-shaped metal layers, and a connection metal layer connecting the common metal layer and the strip-shaped metal layer, the connection metal layer comprising: a first connection wiring directly connected to the common metal layer and extending from the common metal layer in the first direction, a second connection wiring directly connected to the first connection wiring and extending from the first connection wiring in the second direction, and a third connection wiring directly connected to the second connection wiring, extending from the second connection wiring in the first direction and directly connected to the strip-shaped metal layer, wherein an end of the second connection wiring connected to the third connection wiring is located outside a first side edge of the strip-shaped metal layer in the second direction, and the connection metal layer of the dielectric film in the first state and the connection metal layer of the dielectric film in the second state are arranged in point symmetry with respect to the center of the one surface.

[0065] The film capacitor of the present disclosure includes a first dielectric film having a first metal layer disposed on one surface thereof, the first metal layer having a first common metal layer located continuously at a first edge of the first direction of the first surface along a second direction perpendicular to the first direction, and a second common metal layer located continuously at a second edge of the first direction of the first surface along the second direction, and a second dielectric film having a second metal layer disposed on one surface thereof, the second common metal layer having an edge insulating region that is continuous along the second direction perpendicular to the first direction, at each of a first edge and a second edge of the first direction of the first surface. and a first metal electrode and a second metal electrode located on each of a pair of end faces of the film laminate in the first direction and electrically connected to the first metal layer, the first metal layer including a plurality of first strip-shaped metal layers extending in the first direction and electrically connected to the first common metal layer, a plurality of second strip-shaped metal layers extending in the first direction and electrically connected to the second common metal layer, and a first common metal layer including a first common metal layer and a second common metal layer and ... first common metal layer and a second common metal layer and a first common metal layer and a first common metal layer and a second common metal layer and a first common metal layer and a first common metal layer and a first common metal layer and a second common metal layer and a first common metal layer and a first common metal layer and a first common metal layer and a second common metal layer and a first common metal layer and a first common metal layer and a first common metal layer and a second common metal layer and a first common metal layer and a first common metal layer and a second common metal layer and a first common metal layer and a a first connection metal layer connecting the first strip-shaped metal layer and a second connection metal layer connecting the second common metal layer and the second strip-shaped metal layer, the second metal layer being a planar metal layer electrically insulated from the first metal electrode and the second metal electrode by the edge insulating region, the first connection metal layer directly connected to the first common metal layer and including a first connection wiring extending from the first common metal layer in the first direction, a second connection wiring directly connected to the first connection wiring and extending from the first connection wiring in the second direction, and a second connection wiring directly connected to the second connection wiring, a third connection wiring extending from the second connection wiring in the first direction and directly connected to the first strip-shaped metal layer, the second connection metal layer comprising: a fourth connection wiring directly connected to the second common metal layer and extending from the second common metal layer in the first direction; a fifth connection wiring directly connected to the fourth connection wiring and extending from the fourth connection wiring in the second direction; and a sixth connection wiring directly connected to the fifth connection wiring, extending from the fifth connection wiring in the first direction and directly connected to the second strip-shaped metal layer, wherein an end of the second connection wiring connected to the third connection wiring isthe fifth connection wiring is located outside the first side edge of the first strip-shaped metal layer in the second direction, an end of the fifth connection wiring connected to the sixth connection wiring is located outside the first side edge of the second strip-shaped metal layer in the second direction, and the first connection metal layer and the second connection metal layer are arranged in point symmetry with respect to the center of the one surface of the first dielectric film.

[0066] In the linked capacitor of the present disclosure, a plurality of film capacitors, including the above-described film capacitor, are connected by a bus bar.

[0067] The inverter of the present disclosure includes a bridge circuit configured with switching elements, and a capacitance section connected to the bridge circuit and including the above-mentioned film capacitor.

[0068] The electric vehicle of the present disclosure includes a power source, the above-mentioned inverter connected to the power source, a motor connected to the inverter, and wheels driven by the motor.

[0069] According to the present disclosure, even when the film laminate is cut in a predetermined direction, it is possible to provide a laminated film capacitor in which discharge at the cut portion is reduced and loss of capacitance is small.

[0070] According to the present disclosure, it is possible to provide a linked capacitor, an inverter, and an electric vehicle that use a film capacitor with little capacitance loss.

[0071] Although the embodiments of the present disclosure have been described in detail above, the present disclosure is not limited to the above-mentioned embodiments, and various modifications and improvements are possible within the scope of the gist of the present disclosure. It goes without saying that all or part of the components of each of the above-mentioned embodiments can be appropriately combined within the scope of not contradicting each other. [Explanation of symbols]

[0072] 1. Dielectric film (first dielectric film) 2 Dielectric film (second dielectric film) 3 Metal layer (first metal layer) 3Aa First metal strip layer 3Ab First connecting metal layer 3Ab1 1st connection wiring 3Ab2 Second connection wiring 3Ab3 3rd connection wiring 3Ac 1st common metal layer 3Ba 2nd strip metal layer 3Bb Second connecting metal layer 3Bb1 4th connection wiring 3Bb2 5th connection wiring 3Bb3 6th connection wiring 3Bc 2nd common metal layer 3a Metal strip layer 3b connection metal layer 3b1 First connection wiring 3b2 Second connection wiring 3b3 3rd connection wiring 3c common metal layer 4 Film laminate 5A Metallicon (first metal electrode) 5B Metallicon (second metal electrode) 6 Lead Wire 7 Exterior materials 8 Second metal layer 8a Metal strip layer 8b Central connecting layer 10,11 Film capacitors 12 Insulating layer 21 Busbar 21a Terminal section 21b Output terminal section 31 Bridge Circuit 33 Capacity section 35 Boost circuit 3a1 1st side 3a2 2nd side 41 Motor 43 Engine 45 Transmission 47 Inverter 49 Power supply 51a front wheel 51b rear wheel 53 Vehicle ECU 55 Ignition key 57 Engine ECU A Film Capacitor B Coupled capacitor C Inverter D. Electric Vehicles E Electric Vehicle Medium motor S Insulation margin T-Edge Insulation Area Tc Central insulating region

Claims

1. A rectangular parallelepiped film laminate having a metal layer disposed on one surface, and a plurality of dielectric films laminated on a first edge portion of the one surface in a first direction, the dielectric films having an edge insulating region that is continuous along a second direction perpendicular to the first direction, a film laminate in which a dielectric film in a first state and a dielectric film in a second state are laminated, the orientations of the edge insulating regions being inverted so that they overlap every other film in a plan view; a first metal electrode and a second metal electrode located on each of a pair of end faces in the first direction of the film laminate and electrically connected to the metal layer; The metal layer electrically connected to the first metal electrode includes a common metal layer extending in the second direction and located at a second edge of the one surface in the first direction; a plurality of strip-shaped metal layers extending in the first direction and electrically connected to the common metal layer; a connection metal layer connecting the common metal layer and the strip metal layer; the connection metal layer is directly connected to the common metal layer, and a first connection wiring extends from the common metal layer in the first direction; a second connection wiring directly connected to the first connection wiring and extending from the first connection wiring in the second direction; a third connection wiring that is directly connected to the second connection wiring and extends from the second connection wiring in the first direction to be directly connected to the strip-shaped metal layer; an end portion of the second connection wiring connected to the third connection wiring is located outside a first side edge of the strip-shaped metal layer in the second direction; a connecting metal layer of the dielectric film in the first state and a connecting metal layer of the dielectric film in the second state are disposed in point symmetry with respect to a center of the one surface; an end portion of the second connection wiring connected to the first connection wiring is located inside a second side edge of the strip-shaped metal layer opposite to the first side edge in the second direction; Film capacitor.

2. The film capacitor according to claim 1 , wherein the second connection wiring has a meandering shape.

3. A plurality of film capacitors and a bus bar connecting the plurality of film capacitors, A coupled capacitor comprising the film capacitor according to claim 1 or 2.

4. A bridge circuit configured with switching elements and a capacitance unit connected to the bridge circuit, An inverter, wherein the capacitance portion includes the film capacitor according to any one of claims 1 to 3.

5. A vehicle driving device comprising: a power source; an inverter connected to the power source; a motor connected to the inverter; and wheels driven by the motor; An electric vehicle, wherein the inverter is the inverter according to claim 4.

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