JP7663675B2 - Film capacitors, coupled capacitors, inverters and electric vehicles - Google Patents

Description

The present disclosure relates to a film capacitor, a linked capacitor, an inverter and an electric vehicle.

An example of prior art is described in Patent Document 1.

Patent No. 5984097

The film capacitor of the present disclosure includes a rectangular film laminate having a metal layer disposed on one surface thereof, and a plurality of dielectric films laminated on a first edge of the first surface in a first direction, the dielectric films having continuous edge insulating regions 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 relative to each other 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 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 that is directly connected to the common metal layer and extends from the common metal layer in the first direction, a second connection wiring that is directly connected to the first connection wiring and extends from the first connection wiring in the second direction, and a third connection wiring that is directly connected to the second connection wiring, extends from the second connection wiring in the first direction and is 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 the center of the one surface as the point of symmetry.

The film capacitor of the present disclosure is a rectangular parallelepiped film laminate in which 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 surface in a first direction along a second direction perpendicular to the first direction, and a second common metal layer located continuously at a second edge of the first surface in the first direction along the second direction, and a second dielectric film having a second metal layer disposed on one surface thereof, the second metal layer having an edge insulating region that is continuous at each of a first edge and a second edge of the first surface in the first direction along a 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 faces of the film laminate in the first direction and 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 comprises 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, an end of the second connection wiring connected to the third connection wiring is located outside a first side edge of the first strip-shaped metal layer in the second direction, and an end of the fifth connection wiring connected to the sixth connection wiring is located outside a 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 a center of the one surface of the first dielectric film.

The linked capacitor of the present disclosure comprises multiple film capacitors, including the above-mentioned film capacitor, connected together by a bus bar.

The inverter disclosed herein comprises a bridge circuit constituted by switching elements and a capacitance section connected to the bridge circuit and including the above-mentioned film capacitor.

The electric vehicle disclosed herein comprises a power source, the above-mentioned inverter connected to the power source, a motor connected to the inverter, and wheels driven by the motor.

FIG. 2 is a diagram showing the configuration of the film capacitor of the first embodiment, and is a plan view of a dielectric film. 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. FIG. 1 is a diagram showing a configuration of a film capacitor according to a first embodiment, and is a plan view of the film capacitor viewed from above. FIG. 2 is an enlarged plan view of the vicinity of a connecting metal layer of the dielectric film. 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. FIG. 2 is an exploded perspective view showing a laminated state of the dielectric film (before cutting). FIG. 4 is an external perspective view showing the configuration of the film laminate after cutting. FIG. 2 is an external perspective view showing the configuration of the metal electrode after thermal spraying. 13 is an enlarged plan view of the vicinity of a connecting metal layer of a dielectric film in a second embodiment. FIG. 13 is an enlarged plan view of the vicinity of a connecting metal layer of a dielectric film in a second embodiment. FIG. 13 is an enlarged plan view of the vicinity of a connecting metal layer of a dielectric film in a third embodiment. FIG. 13 is an enlarged plan view of the vicinity of a connecting metal layer of a dielectric film in a fourth embodiment. FIG. FIG. 13 is a diagram showing the configuration of a film capacitor according to a fifth embodiment, and is a plan view of a dielectric film. FIG. 13 is a diagram showing the configuration of a film capacitor according to a fifth embodiment, and is a plan view of a dielectric film. FIG. 13 is a diagram showing the configuration of a film capacitor according to a fifth embodiment, and is a schematic cross-sectional view showing the laminated state of the film. 2 is an enlarged plan view of the vicinity of a first connection metal layer and a second connection metal layer; FIG. 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. 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. FIG. 13 is a diagram showing the configuration of a film capacitor according to a sixth embodiment, and is a schematic cross-sectional view showing the laminated state of the film. FIG. 13 is an external perspective view showing a modified example of the film capacitor. FIG. 1 is a perspective view showing a schematic configuration of a coupled capacitor. FIG. 2 is a schematic diagram for explaining the configuration of an inverter. FIG. 1 is a schematic diagram for explaining the configuration of an electric vehicle.

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

The film capacitor of the basic configuration of this disclosure is constructed by winding or stacking multiple metallized films in one direction, with a metal film that serves as an electrode vapor-deposited on the surface of a dielectric film containing, for example, polypropylene resin.

Of these, in laminated film capacitors, when the laminate of metallized films is cut to the required size, the metal film is also cut, and the metal film is exposed at the cut surface. When the film capacitor is in use, if a voltage is applied to the exposed metal film, a discharge occurs at the cut surface.

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.

However, while 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 near the cut surfaces in the film laminate.

The object of the present disclosure is to provide a laminated film capacitor, a linked capacitor, an inverter, and an electric vehicle that reduce discharge at the end faces and have low capacitance loss.

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

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.

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

In each figure, the direction in which the strip metal layers 3a positioned parallel to each other extend is called the first direction, and the direction in which the parallel strip metal layers 3a are arranged is called the second direction. The film is stacked 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 the y direction, and the third direction the z direction. Details of the film laminate 4 after stacking will be described later.

Each strip-shaped metal layer 3a on the surface of the dielectric films 1 and 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, the film surface (hereinafter, insulating margin S) is exposed, so that each strip-shaped metal layer 3a is electrically insulated. Each insulating margin S is connected to an edge insulating region T that continues in the second direction (y direction) at the 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 in the y direction of each strip-shaped metal layer 3a and the width P2 in the y direction of each insulating margin S (P = P1 + P2).

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., at the second edge in the first direction. Each strip metal layer 3a is electrically insulated from the others by an insulating margin S, but is electrically connected as a whole to the metal layers 3 by connecting them to one common metal layer 3c.

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 the base film is broken down and a strip metal layer 3a is shorted to another strip metal layer 3a, causing a current greater than the specified level to flow, the connection metal layer 3b burns off, causing a break in the connection, preventing the entire film capacitor 10 from stopping functioning.

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 and directly connects to the strip 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, "extended 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" refers to a case where 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 value than the strip-shaped metal layer 3a, and functions as a fuse.

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 edge 3a1 of the strip metal layer 3a in the second direction. The third connection wiring 3b3 extends, for example, from the second connection wiring 3b2 in the first direction and directly connects to the first side edge 3a1 of the strip metal layer 3a. 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 edge 3a2 of the strip metal layer 3a in the second direction, or may be located inside the second side edge 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.

3, the connection metal layer 3b of the dielectric film 1 in a first state and the connection metal layer 3b of the dielectric film 2 in a second state, the orientation of which is reversed from that of the first state, are arranged in point symmetry with respect to the center of one surface of the base film. In other words, when the film laminate 4 is viewed in the z direction, if the connection metal layer 3b of the dielectric film 1 is rotated 180° around the symmetric point, it will have the same shape as the connection metal layer 3b of the dielectric film 2.

During the manufacture of the film capacitor 10, 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 always at the same position in the width direction of the strip metal layer 3a. The cut strip metal layer 3a is exposed at the end face of the film capacitor 10 in the second direction (y direction). If the strip metal layer 3a is in a conductive state with the common metal layer 3c even after cutting, a voltage is applied to the strip metal layer 3a during use, causing discharge at the end face. When the strip 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 or 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 metal layer 3a and the common metal layer 3c are electrically insulated. This makes it possible to reduce discharge at the end faces 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.

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

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

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 metallicon 5A (first metal electrode) and the other is called metallicon 5B (second metal electrode), but they only differ in their placement positions and have no difference in structure. For example, metallicon 5A is electrically connected to the common metal layer 3c of the dielectric film 1 and is also electrically connected to each strip-shaped metal layer 3a through the common metal layer 3c. In addition, the metal layer 3 of the dielectric film 1 and metallicon 5B are electrically insulated by the edge insulating region T. On the other hand, metallicon 5B is electrically connected to the common metal layer 3c of the dielectric film 2 and is also electrically connected to each strip-shaped metal layer 3a through the common metal layer 3c. In addition, the metal layer 3 of the dielectric film 2 and metallicon 5A are electrically insulated by the edge insulating region T.

Figures 4 to 6 are diagrams that explain the process of manufacturing a film capacitor. In Figures 4 to 6, as in Figures 1A to 1C, the extension direction of the parallel strip-shaped metal layers 3a is the first direction (x direction in the figure), the extension direction of the common metal layer 3c (y direction perpendicular to the x direction) is the second direction, and the lamination direction of the film perpendicular to the first and second directions is the third direction (z direction).

In manufacturing the laminated film capacitor 10, first, as shown in FIG. 4, multiple dielectric films 1 and 2 each having a plurality of continuous strip-shaped metal layers 3a 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 is inverted 180° for each film so that the planar positions of the edge insulating regions T overlap every other film.

As mentioned 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, this is not limited to this, and the configuration of the dielectric film 1 and the dielectric film 2 may be different. For example, in a state where the dielectric film 1 and the dielectric film 2 are stacked so that the planar positions of the edge insulating regions T overlap every other sheet, 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 other words, the dielectric film 1 and the dielectric film 2 differ 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.

Figure 5 shows the film laminate 4 after being cut to a specified length, viewed from the cut surface (y-direction end surface). As shown in this Figure 5, the dielectric films 1 and 2 adjacent to each other are laminated with a slight shift in position (offset state) 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 Figure 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.

In addition, an insulating layer 12 that serves as a protective layer for the film laminate 4, such as a base film that does not have 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.

6, a first metal electrode and a second metal electrode (metallicon 5A, 5B) are formed by metal spraying on both end faces in the x direction of the film laminate 4 where the previously 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 metallicon 5A or 5B via the common metal layer 3c, and functions as an internal electrode of the film capacitor 10.

Below, other embodiments of the film capacitor will be described. In the other embodiments, only the configuration of the connection metal layer 3b differs from that of the first embodiment described above, 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 that is connected to the third connection wiring 3b3 is located outside the first side edge 3a1 of the strip-shaped metal layer 3a in the second direction.

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 when the strip metal layer 3a is shorted, the first connection wiring 3b1 is more likely to break, 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.

The second connection wiring 3b2 of the second embodiment has a larger wiring width than the second connection wiring 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 lowering the ESR, the allowable value of the ripple current of the film capacitor 10 can be increased.

Figure 8 shows the connection metal layer 3b of the third embodiment. As shown in Figure 8, in the third embodiment, the second connection wiring 3b2 has a meandering shape (meander shape). In the first embodiment, the second connection wiring 3b2 has a straight shape, whereas in the third embodiment, it has a meandering shape. In the connection metal layer 3b of the third embodiment, the second connection wiring 3b2 has a meandering shape to ensure the wiring length of the second connection wiring 3b2. Even if insulation breakdown occurs in the dielectric films 1 and 2 and 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 makes it possible to suppress the excessive operation of the fuse, which causes the strip-shaped metal layer 3a to be insulated from the common metal layer 3c, and the capacitance of the film capacitor 10 to decrease early.

In each of the above embodiments, the film laminate 4 is formed by laminating the dielectric films 1 and 2 with the x-direction orientation alternately inverted, and the dielectric films 1 and 2 have the same configuration but different orientations. This is not limited to the above, 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 other than the edge insulating area T, that is, a so-called solid pattern of a full metal layer, may be used. The metallicon 5A (first metal electrode) is electrically connected to the common metal layer 3c of the dielectric film 1. The metallicon 5B (second metal electrode) is electrically connected to the full metal layer of the dielectric film.

Figure 9 shows the connection metal layer 3b of the fourth embodiment. As shown in Figure 9, in the fourth embodiment, unlike the first to third embodiments, the end of the second connection wiring 3b2 continuing to the first connection wiring 3b1 is located 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 connection metal layer 3b of the dielectric film 1 in the first state and the connection 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.

A film capacitor according to a fifth embodiment of the present disclosure will be described. Figures 10A to 10C are diagrams showing the configuration of the film capacitor according to the fifth embodiment. Figures 10A and 10B are plan views of a dielectric film, and Figure 10C is a schematic cross-sectional view showing the laminated state of the film. The film capacitor 11 of this embodiment has metallikon 5A and metallikon 5B on both end surfaces of the 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 side of the base film as shown in Figure 10A, and a dielectric film (second dielectric film) 2 having a second metal layer 8 on one side of the base film as shown in Figure 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.

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 connection 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 connection 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 in an electrically insulated state. 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.

The first connection metal layer 3Ab includes a first connection wiring 3Ab1 that is directly connected to the first common metal layer 3Ac and extends from the first common metal layer 3Ac in a first direction, a second connection wiring 3Ab2 that is directly connected to the first connection wiring 3Ab1 and extends from the first connection wiring 3Ab1 in a second direction, and a third connection wiring 3Ab3 that is directly connected to the second connection wiring 3Ab2, extends from the second connection wiring 3Ab2 in the first direction, and directly connects 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 that is connected to the third connection wiring 3Ab3 of the first connection metal layer 3Ab is located outside the first side edge 3a1 of the first strip-shaped metal layer 3Aa in the second direction.

The second connection metal layer 3Bb includes a fourth connection wiring 3Bb1 that is directly connected to the second common metal layer 3Bc and extends from the second common metal layer 3Bc in the first direction, a fifth connection wiring 3Bb2 that is directly connected to the fourth connection wiring 3Bb1 and extends from the fourth connection wiring 3Bb1 in the second direction, and a sixth connection wiring 3Bb3 that is directly connected to the fifth connection wiring 3Bb2, extends from the fifth connection wiring 3Bb2 in the first direction, and directly connects to the second strip-shaped metal layer 3Ba. The second connection metal layer 3Bb configured in this manner 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 that is connected to the sixth connection wiring 3Bb3 located outside the first side edge 3a1 of the second strip-shaped metal layer 3Ba in the second direction.

Figure 11 is an enlarged plan view of the vicinity of the first connecting metal layer and 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 the center of one surface of the base film as the symmetric point. 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 degrees around the symmetric point, it will have the same shape as the second connecting metal layer 3Bb.

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 of the dielectric film 2 in the first direction 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.

In a plan view, the film laminate 4 is laminated so 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. The film capacitor 11 of this embodiment, which includes such a film laminate 4, can be a series capacitor in which the first metal layer 3 and the second metal layer 8 connect the laminated film capacitors in series. The film capacitor 11 is a laminated 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 metallicon 5A side, and a laminated 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 metallicon 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.

In this embodiment, for example, 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 in a planar view, and the second metal layer 8 does not overlap the first connection metal layer 3Ab, the first common metal layer 3Ac, the second connection metal layer 3Bb, or the second common metal layer 3Bc. The second metal layer 8 may also include a plurality of planar metal layers, each of which may overlap the first strip-shaped metal layer 3Aa and the second strip-shaped metal layer 3Ba in a planar view.

In the film capacitor 11 of this embodiment, regardless of the position of the cutting line cut in the film laminate 4, at least one of the second connection wiring 3Ab2 and the fifth connection wiring 3Bb2 of the dielectric film 1 intersects with the cutting line, 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 reduces discharge at the end faces of the film capacitor 11. Furthermore, since 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, the film capacitor 11 can have a small loss of capacitance.

A film capacitor according to a sixth embodiment of the present disclosure will be described. Figures 12A to 12C are diagrams showing the configuration of the film capacitor according to the sixth embodiment. Figures 12A and 12B are plan views of the dielectric film, and Figure 12C is a schematic cross-sectional view showing the laminated state of the film. In the sixth embodiment, 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 are different from those of the fifth embodiment, but the other configurations are common. In the fifth embodiment, the first connection metal layer 3Ab and the second connection metal layer 3Bb are point symmetric in the dielectric film 1, whereas in the first metal layer 3 of this embodiment, the first connection metal layer 3Ab and the second connection metal layer 3Bb are line symmetric across 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 connection layer 8b that connects the strip-shaped metal layers 8a to each other at the center 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.

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 can be obtained with little loss of capacitance.

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

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

Figure 14 is a perspective view showing a schematic configuration of a linked capacitor. In Figure 14, the case and molding resin are omitted to make the configuration easier to understand. Linked capacitor B is configured with multiple film capacitors A 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.

Figure 15 is a schematic diagram for explaining the configuration of an inverter. Figure 15 shows an example of an inverter C that produces AC from rectified DC. As shown in Figure 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.

The input of the inverter C may be connected to a boost circuit 35 that boosts the voltage of the DC power supply, or 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.

Figure 16 is a schematic diagram for explaining the configuration of an electric vehicle. Figure 16 shows an example of a hybrid electric vehicle (HEV) as an electric vehicle D.

The electric vehicle D in Figure 16 is equipped with a drive motor 41, an engine 43, a transmission 45, an inverter 47, a power source (battery) 49, front wheels 51a and rear wheels 51b.

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.

The electric vehicle D shown in FIG. 16 is equipped with 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 is further equipped with driving devices such as an ignition key 55 operated by a driver, an accelerator pedal (not shown), and a brake. A drive 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 drive 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.

In addition, 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 (EVs), electric bicycles, generators, and solar cells.

This disclosure may have the following embodiments:

The film capacitor of the present disclosure is 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 a continuous edge insulating region along a second direction perpendicular to the first direction, the film laminate including a dielectric film in a first state and a dielectric film in a second state, the orientations of which are inverted 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 being a common metal layer extending in the second direction, the common metal layer extending in the first direction and 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.

The film capacitor of the present disclosure is a rectangular parallelepiped film laminate in which 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 along a second direction perpendicular to the first direction at a first edge of the first surface in the first direction, and a second common metal layer located continuously along the second direction at a second edge of the first surface in the first 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 surface in the first direction, the second common metal layer being disposed continuously along the second direction at each of the first edge and the second edge of the first surface in the first direction, the second common metal layer being disposed continuously along the second direction at each of the first edge and the second edge of the first surface in the first direction, and a part of the first metal layer is laminated. the first metal layer includes a film laminate in which a portion of the first metal layer and a portion of the second metal layer overlap each other, and 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 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, 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, 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; and a fourth connection wiring directly connected to the second common metal layer and extending from the second common metal layer in the first direction, and 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 that is directly connected to the line 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 band-shaped metal layer, wherein an end of the second connection wiring that is connected to the third connection wiring is located outside a first side edge of the first band-shaped metal layer in the second direction, and an end of the fifth connection wiring that is connected to the sixth connection wiring is located outside a first side edge of the second band-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.

The linked capacitor of the present disclosure comprises multiple film capacitors, including the above-mentioned film capacitor, connected together by a bus bar.

The inverter disclosed herein comprises a bridge circuit constituted by switching elements and a capacitance section connected to the bridge circuit and including the above-mentioned film capacitor.

The electric vehicle disclosed herein comprises a power source, the above-mentioned inverter connected to the power source, a motor connected to the inverter, and wheels driven by the motor.

According to the present disclosure, even if the film laminate is cut in a specified direction, it is possible to produce a laminated film capacitor that reduces discharge at the cut portion and has little loss of capacitance.

According to the present disclosure, it is possible to provide a linked capacitor, inverter, and electric vehicle using a film capacitor with low capacitance loss.

Although the embodiments of the present disclosure have been described in detail above, the present disclosure is not limited to the above-described embodiments, and various modifications, improvements, etc. are possible without departing from the gist of the present disclosure. It goes without saying that all or part of the components of each of the above-described embodiments can be combined as appropriate and consistent.

1. Dielectric film (first dielectric film)
2 Dielectric film (second dielectric film)
3 Metal layer (first metal layer)
3Aa First strip-shaped metal layer 3Ab First connection metal layer 3Ab1 First connection wiring 3Ab2 Second connection wiring 3Ab3 Third connection wiring 3Ac First common metal layer 3Ba Second strip-shaped metal layer 3Bb Second connection metal layer 3Bb1 Fourth connection wiring 3Bb2 Fifth connection wiring 3Bb3 Sixth connection wiring 3Bc Second common metal layer 3a Strip-shaped metal layer 3b Connection metal layer 3b1 First connection wiring 3b2 Second connection wiring 3b3 Third connection wiring 3c Common metal layer 4 Film laminate 5A Metallikon (first metal electrode)
5B Metallicon (second metal electrode)
DESCRIPTION OF SYMBOLS 6 Lead wire 7 Exterior member 8 Second metal layer 8a Strip-shaped metal layer 8b Central connection layer 10, 11 Film capacitor 12 Insulating layer 21 Bus bar 21a Terminal portion 21b Lead-out terminal portion 31 Bridge circuit 33 Capacitor portion 35 Boost circuit 3a1 First side 3a2 Second side 41 Motor 43 Engine 45 Transmission 47 Inverter 49 Power source 51a Front wheel 51b Rear wheel 53 Vehicle ECU
55 Ignition key 57 Engine ECU
A Film capacitor B Linked capacitor C Inverter D Electric vehicle E Electric vehicle M Motor S Insulation margin T Edge insulation area Tc Center insulation area

Claims (5)

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. The film capacitor according to claim 1 , wherein the second connection wiring has a meandering shape. 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 . A bridge circuit configured with switching elements and a capacitance unit connected to the bridge circuit,
An inverter, wherein the capacitance section includes the film capacitor according to any one of claims 1 to 3 . 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 .