Film capacitors, junction capacitors, inverters, and electric vehicles

Abstract

The film capacitor disclosed in the present invention includes: a stacked body, which is formed by alternately stacking at least one dielectric film including a polyarylate film and a plurality of metal vapor-deposited films; a covering film, which contains a polyester hot-melt adhesive resin, and the covering film is stacked on two first side surfaces, and the two first side surfaces are opposite to each other in a first direction orthogonal to the stacking direction of the stacked body; and metal sprayed electrodes are stacked on two second side surfaces, and the two second side surfaces are opposite to each other in a second direction orthogonal to the stacking direction of the stacked body and perpendicular to the first direction.

Description

Technical Field

[0001] The present disclosure relates to a film capacitor and a junction type capacitor, and an inverter and an electric vehicle using the same. Background Art

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

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent No. 5990325 Summary of the invention

[0006] The film capacitor disclosed in the present invention includes: a stacked body, which is formed by alternately stacking at least one dielectric film including a polyarylate film and a plurality of metal vapor-deposited films; a covering film, which contains a polyester hot-melt adhesive resin, and the covering film is stacked on two first side surfaces, and the two first side surfaces are opposite to each other in a first direction orthogonal to the stacking direction of the stacked body; and metal sprayed electrodes are stacked on two second side surfaces, and the two second side surfaces are opposite to each other in a second direction orthogonal to the stacking direction of the stacked body and perpendicular to the first direction.

[0007] Furthermore, a connection type capacitor of the present disclosure includes: a plurality of thin film capacitors; and a bus bar connecting the plurality of thin film capacitors; the plurality of thin film capacitors includes the above-mentioned thin film capacitor.

[0008] Furthermore, an inverter of the present disclosure includes: a bridge circuit formed of switching elements; and a capacitor connected to the bridge circuit; and the capacitor includes the above-mentioned film capacitor.

[0009] In addition, the electric vehicle disclosed herein includes: a power source; an inverter connected to the power source; a motor connected to the inverter; and wheels driven by the motor; wherein the inverter is the inverter described above. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0011] Figure 1 It is a perspective view showing an example of a stacked film capacitor according to an embodiment of the present disclosure.

[0012] Figure 2 is from Figure 1 Cross-sectional view observed along section line Ⅱ-Ⅱ.

[0013] Figure 3 is from Figure 1 Cross-sectional view observed along section line III-III.

[0014] Figure 4 This is a schematic diagram of a test piece used to check the bonding state.

[0015] Figure 5 It is a perspective view showing an example of a junction type capacitor.

[0016] Figure 6 This is a schematic configuration diagram for explaining an example of an inverter.

[0017] Figure 7 This is a schematic diagram showing an example of an electric vehicle. DETAILED DESCRIPTION

[0018] The laminated film capacitor, which is the basic structure of the laminated film capacitor disclosed in the present invention, is mostly made into a single-piece body by cutting a long strip of laminated body, so it is necessary to improve the insulation of the cut surface. Patent document 1 records that in a laminated polypropylene film capacitor using a polypropylene film as a dielectric film, in order to reduce the discharge of two side surfaces exposed to the outside adjacent to two side surfaces formed with metal spraying electrodes when a voltage is applied, a cover film containing a polypropylene-based hot-melt resin is welded on the side surfaces exposed to the outside.

[0019] Figure 1 It is a perspective view showing an example of a stacked film capacitor according to an embodiment of the present disclosure. Figure 2 is from Figure 1 Cross-sectional view observed along section line Ⅱ-Ⅱ. Figure 3 is from Figure 1 The cross-sectional view observed along the section line Ⅲ-Ⅲ. Figure 1-Figure 3 As shown, the stacked film capacitor A comprises: a film capacitor body 3, a pair of first metal sprayed electrodes 4a, and a second metal sprayed electrode 4b. Hereinafter, the film capacitor body 3 may be referred to as the body 3. The body 3 is stacked with a first dielectric film 1a, a first metal vapor-deposited film 2a, a second dielectric film 1b, and a second metal vapor-deposited film 2b. The body 3 is a rectangular parallelepiped, and has a pair of first faces 3a and 3b opposite to each other in the stacking direction of the dielectric film and the metal vapor-deposited film, and between the first faces 3a and 3b, there is a pair of first side faces 3c and 3d connected to the first faces 3a and 3b and a pair of second side faces 3e and 3f. In addition, in the following figures, for ease of explanation, the size of each part is exaggerated, and the actual thickness of each part is very small relative to the size of the body 3.

[0020] The first metallization electrode 4a and the second metallization electrode 4b are provided on the first side surface 3c and 3d of the main body 3 by metallization. Electrically insulating coatings 16a and 16b are provided on the second side surfaces 3e and 3f of the main body 3.

[0021] like Figure 2 The main body 3 of the stacked film capacitor A shown in the figure has a first metallized film 6a having a first metal vapor-deposited film 2a on a surface 1ac of a first dielectric film 1a and a second metallized film 6b having a second metal vapor-deposited film 2b on a surface 1bc of a second dielectric film 1b alternately stacked. The first metal vapor-deposited film 2a is electrically connected to the first metal sprayed electrode 4a on the first side surface 3c of the main body 3. The second metal vapor-deposited film 2b is electrically connected to the second metal sprayed electrode 4b on the first side surface 3d of the main body 3. Figure 1 The direction of the first and second metallization electrodes 4a and 4b is the first direction x, and the direction of the cover films 16a and 16b is the second direction y. The thickness direction of the first and second dielectric films 1a and 1b, that is, the stacking direction is the third direction z.

[0022] The first metallized film 6a is formed by forming the first metal vapor-deposited film 2a on the surface 1ac of the first dielectric film 1a. The first metallized film 6a has an insulating blank portion 7a near the side surface 1af on the surface 1ac, and the first metal vapor-deposited film 2a is not formed in the insulating blank portion 7a, that is, the exposed portion of the first dielectric film 1a is continuously present in the second direction y.

[0023] The second metallized film 6b is formed by forming the second metal vapor-deposited film 2b on the surface 1bc of the second dielectric film 1b. The second metallized film 6b has an insulating blank portion 7b near the side surface 1bf on the surface 1bc, and the second metal vapor-deposited film 2b is not formed in the insulating blank portion 7b, that is, the exposed portion of the second dielectric film 1b is continuously present in the second direction y.

[0024] like Figure 2 As shown, these metalized films 6a and 6b are stacked in a state where they are slightly offset from each other in the first direction x, which is the width direction.

[0025] When there is a potential difference between the first metal vapor-deposited film 2a and the second metal vapor-deposited film 2b, electrostatic capacitance is generated in the effective region 8 where the first metal vapor-deposited film 2a and the second metal vapor-deposited film 2b overlap each other with the first dielectric film 1a or the second dielectric film 1b interposed therebetween.

[0026] This type of stacked film capacitor A is obtained as follows. The long strip-shaped first metallized film 6a and the second metallized film 6b are slightly offset from each other in the first direction x, which is the width direction, and are overlapped and stacked to produce a stacked body. The first metal sprayed electrode 4a is formed on the first side 3c of the obtained stacked body located in the first direction x, and the second metal sprayed electrode 4b is formed on the first side 3d. The stacked body having the metal sprayed electrode 4 (i.e., the first metal sprayed electrode 4a and the second metal sprayed electrode 4b) is cut along the first direction x and divided into individual components. The metal sprayed electrode 4 can also be formed on each main body 3 after the stack is cut. The cross section of the stack after being cut becomes the second side 3e, 3f of each main body 3.

[0027] In order to explain the features of this embodiment that are common to first metallized film 6a and second metallized film 6b of film capacitor A, the following description may be omitted. Figure 3 The symbols a and b shown in the figure are abbreviations for the dielectric film 1, the metal vapor-deposited film 2, the metal sprayed electrode 4, the metallized film 6, and the like.

[0028] Then, if Figure 1-Figure 3 As shown, in the film capacitor A of the present embodiment, in particular, among the four side surfaces 3c, 3d, 3e, and 3f of the film capacitor element 12 formed by stacking the metallized films 6a and 6b, the side surfaces 3c, 3d, 3e, and 3f of the film capacitor element 12 are located in the length direction ( Figure 3 The entire surfaces of the other two side surfaces 3e and 3f on both sides (in the left-right direction) of the substrate are covered with cover films 16a and 16b respectively and isolated from the outside, thereby being adjacent to the two side surfaces 3c and 3d on which the metal sprayed electrodes 4a and 4b are formed. In addition, the two layers of cover films 16a and 16b are thermally fused (melt-bonded) to the side surfaces of the dielectric films 1a and 1b of the metallized thin films 6a and 6b exposed on the two side surfaces 3e and 3f.

[0029] Therefore, the film capacitor A of the present embodiment reduces the generation of leakage current from the two side surfaces 3e and 3f, and the creepage distance between the metal vapor-deposited films 2a and 2b of the metallized films 6a and 6b is increased, which advantageously reduces the short circuit caused by discharge between the metal vapor-deposited films 2a and 2b, thereby improving the withstand voltage. In addition, the side surfaces of the dielectric films 1a and 1b of the metallized films 6a and 6b exposed on the two side surfaces 3e and 3f are completely in close contact with the cover films 16a and 16b, thereby preventing moisture or air from entering between the side surfaces of the dielectric films 1a and 1b (and further the side surfaces of the metallized films 6a and 6b) and the cover films 16a and 16b.

[0030] The two-layer covering films 16a, 16b are made of a film containing a polyester hot melt adhesive resin which is of the same series as the polyarylate of the dielectric films 1a, 1b constituting the metallized films 6a, 6b and has excellent thermal bonding (melt adhesion) to the polyarylate, i.e., a so-called polyester hot melt adhesive film. By using the two-layer covering films 16a, 16b containing such a resin material, the two-layer covering films 16a, 16b are reliably and firmly welded to the side surfaces of the dielectric films 1a, 1b of the metallized films 6a, 6b exposed on the two side surfaces 3e, 3f of the film capacitor element 12.

[0031] Figure 4 Schematic diagram of a test piece for confirming the bonding state. A rectangular plate A including a polyarylate plate with a vertical side a=25mm, a horizontal side b=33mm, and a thickness t=2-5mm is bonded by heat treating a plate B including a polyethylene terephthalate resin of the same series as the polyarylate at 100°C, or a plate B including a polycarbonate resin at 180°C. The bonding state is confirmed to show that the polyethylene terephthalate plate and the polycarbonate plate are firmly bonded to the polyarylate plate together.

[0032] In addition, although the two layers of covering films 16a and 16b need to be films containing polyester hot melt adhesive resin, the specific type and composition of the polyester hot melt adhesive resin constituting the two layers of covering films 16a and 16b are not particularly limited. That is, various conventionally known polyester hot melt adhesive resins can be used as the molding material of the two layers of covering films 16a and 16b.

[0033] When the two layers of cover films 16a and 16b made of polyester hot melt resin are laminated to cover the entire surface of the side surfaces 3e and 3f of the film capacitor element 12, for example, the following method can be used.

[0034] That is, as a first method, for example, the following method can be adopted: a polyester hot melt adhesive resin heated to a molten state is sprayed through a nozzle or applied with a roller to form a film with a predetermined thickness on the entire surface of the side surfaces 3e and 3f of the film capacitor element 12, and at the same time, the end portions of the side surfaces of the dielectric films 1a and 1b including the metallized films 6a and 6b exposed to the side surfaces 3e and 3f of the film capacitor element 12 are molten by the heat of the molten polyester hot melt adhesive resin, and then they are cooled and solidified. Thus, the two layers of cover films 16a and 16b including the polyester hot melt adhesive film cover the entire side surfaces 3e and 3f of the film capacitor element 12 and are welded to the side surfaces of the dielectric films 1a and 1b to be stacked.

[0035] In addition, as a second method, for example, the following method can also be used: in a laminated configuration state where a polyester hot melt adhesive film covers the entire surface of the side surfaces 3e and 3f of the film capacitor element 12, while heating and melting the polyester hot melt adhesive film, the end portions of the side surfaces of the dielectric films 1a and 1b including the metallized films 6a and 6b exposed to the side surfaces 3e and 3f of the film capacitor element 12 are melted, and then cooled and solidified. In this way, the two layers of covering films 16a and 16b can be laminated to cover the entire surface of the side surfaces 3e and 3f of the film capacitor element 12 and be fused to the side surfaces of the dielectric films 1a and 1b. In addition, the polyester hot melt adhesive film laminated on the side surfaces 3e and 3f of the film capacitor element 12 can be a product having a normal film form, for example, a semi-molten state extrusion molded product extruded by a specific die, etc. can also be used.

[0036] Then, the thickness of the covering films 16a and 16b formed on the side surfaces 3e and 3f of such a film capacitor element 12 is not particularly limited, but can also be about 0.1-1000μm. This is because if the thickness of the covering films 16a and 16b is less than 0.1μm, it is too thin, and it may be difficult to make the creepage distance of the metal vapor-deposited films 2a and 2b of the metallized films 6a and 6b sufficiently long, and it may be difficult to fully obtain the improvement effect of the withstand voltage brought about by the increase in the creepage distance. In addition, even if the thickness of the covering films 16a and 16b exceeds 1000μm, it is difficult to expect to further improve the effect brought about by the formation of the covering films 16a and 16b, and it may instead cause the disadvantage of increasing the formation cost of the covering films 16a and 16b. Therefore, the thickness of the covering films 16a and 16b can be less than 1000μm.

[0037] In addition, when the cover films 16a and 16b are welded to the side surfaces of the dielectric films 1a and 1b of the metallized films 6a and 6b, a resin having a lower melting point than the polyarylate constituting the dielectric films 1a and 1b and having good wettability to the polyarylate is used as the polyester hot melt adhesive resin constituting the two cover films 16a and 16b. The resin having good wettability means a resin that maintains the connection strength with the polyarylate.

[0038] When manufacturing the film capacitor element 12, generally, a long protective film is further laminated on both side end surfaces of a long laminated body formed by alternately staggering and laminating a plurality of long metalized films 6a and 6b in the width direction, thereby forming a long film capacitor element substrate. Then, the long film capacitor element substrate is cut in the width direction at a plurality of positions spaced a certain distance apart in the length direction by using a cutting blade such as a rotary saw blade, thereby performing an operation of manufacturing a plurality of film capacitor elements 12 at one time. Then, the side surfaces 3c and 3d on both sides in the width direction of the film capacitor element 12 thus obtained are used as the formation surfaces 3e and 3f of the two metal sprayed electrodes 4a and 4b, and at the same time, the side surfaces 3e and 3f on both sides in the length direction of the film capacitor element 12 including the cut surface of the film capacitor element substrate are used as the formation surfaces of the two layers of the cover films 16a and 16b.

[0039] When the covering films 16a and 16b are applied at a temperature significantly exceeding the glass transition temperature (Tg) of polyarylate 220°C, the film capacitor element 12 side softens, increasing the possibility of deformation or poor self-recovery. Therefore, a polyester resin having a melting point of 150-250°C, which is equal to or lower than the Tg of polyarylate 220°C, good wettability, and a Tg of 50-160°C is used as the covering films 16a and 16b.

[0040] Since the polyester hot melt adhesive resin constituting the covering films 16a and 16b has a lower melting point than the polyarylate constituting the resin material of the dielectric films 1a and 1b, when the covering films 16a and 16b are fused to the side surfaces 3e and 3f of the dielectric films 1a and 1b (when the covering films 16a and 16b are formed on the side surfaces 3e and 3f of the film capacitor element 12), the heat of the polyester hot melt adhesive resin constituting the covering films 16a and 16b in a molten state can reduce deformation or poor self-recovery of the dielectric films 1a and 1b. By using a polyester hot melt adhesive resin with a low Tg, it is possible to have good wettability to polyarylate and maintain the connection strength with polyarylate, so by applying such a material, it is possible to reduce the peeling of the covering films 16a and 16b fused to the dielectric films 1a and 1b from the dielectric films 1a and 1b. Furthermore, it is possible to meet the use temperature of the high temperature heat-resistant film capacitor of 125°C to 150°C.

[0041] As the polyester hot melt resin constituting the cover films 16a and 16b, a resin having a melt viscosity in the range of about 500 to 50,000 mPa·s at 150 to 250°C is used.

[0042] As can be seen from the above description, in the film capacitor A of the present embodiment, the two layers of cover films 16a, 16b are formed to cover the entire surface of the remaining two side surfaces 3e, 3f other than the side surfaces 3c, 3d as the formation surfaces of the metal spray electrodes 4a, 4b, thereby substantially reducing the leakage current generated from the two side surfaces 3e, 3f, and advantageously increasing the creepage distance between the metal vapor-deposited films 2a, 2b of each metallized film 6a, 6b. Furthermore, the two layers of cover films 16a, 16b are made of polyester-based hot melt adhesive resin, and the two layers of cover films 16a, 16b are fused to the side surfaces of the dielectric films 1a, 1b containing polyarylate of each metallized film 6a, 6b exposed to the two side surfaces 3e, 3f, so that the side surfaces of these dielectric films 1a, 1b are completely in close contact with the cover films 16a, 16b, and no minute gap is formed therebetween. As a result, the intrusion of water vapor or air into the side surfaces of the dielectric films 1a, 1b and between the cover films 16a, 16b is extremely effectively and reliably reduced. In addition, combined with the increase in the creepage distance between the metal vapor-deposited films 2a, 2b, the deterioration of the dielectric films 1a, 1b or the metal vapor-deposited films 2a, 2b due to contact with water vapor can be advantageously reduced, while the discharge between the metal vapor-deposited films 2a, 2b is prevented, thereby effectively improving the withstand voltage.

[0043] The surface of the metal vapor-deposited film 2a, 2b or the metal spray-deposited electrode 4a, 4b is oxidized and has Al-O-Al, hydroxyl or carboxylic acid groups. The existing polyolefin resin used as the covering film is a low-polarity resin. Since it does not contain a carboxylic acid group or a hydroxyl group, it has a small interaction with the metal oxide (small van der Waals force and no hydrogen bond). On the other hand, the polyester resin used for the covering film 16a, 16b is a polar resin, containing an ether bond, a carbonyl group, a carboxylic acid or a hydroxyl group, so it has a large interaction with the metal oxide (large van der Waals force and hydrogen bond). Therefore, the interaction between the covering film 16a, 16b of this embodiment and the metal vapor-deposited film 2a, 2b and the metal spray-deposited electrode 4a, 4b is greater than that of the existing covering film. As a result, the peeling of the covering film 16a, 16b welded to the side 3e, 3f can be more effectively reduced.

[0044] Moreover, in the film capacitor A, the above-mentioned advantageous features can be exerted simply by forming the relatively thin cover films 16a and 16b including a resin film on the two side surfaces 3e and 3f. Therefore, since the above-mentioned features are ensured, it is not necessary to enlarge the film capacitor A as a whole, and the cost burden will not increase.

[0045] Therefore, in the thin film capacitor of the present embodiment as described above, the generation of leakage current can be substantially reduced, while the required capacitor performance can be maintained more stably for a long time, and the withstand voltage can be greatly improved without causing any increase in size or manufacturing cost.

[0046] Figure 5 This is a perspective view schematically showing one example of a junction type capacitor. Figure 5 In order to make it easier to understand the structure of the connection type capacitor, the description of the shell and the outer resin covering the surface of the capacitor is omitted. In the connection type capacitor C, multiple stacked film capacitors are connected in parallel through a pair of bus bars 21 and 23. The bus bars 21 and 23 have terminal parts 21a and 23a for external connection and lead terminal parts 21b and 23b. The lead terminal parts 21b and 23b are connected to the metal sprayed electrodes 4a and 4b of the film capacitor respectively.

[0047] If the thin film capacitor A having the above-described cover films 16 a and 16 b is included in the thin film capacitor of the connection type capacitor C, a connection type capacitor C in which the insulation resistance is unlikely to decrease can be obtained.

[0048] The connection type capacitor C may include at least one thin film capacitor A or two or more thin film capacitors A. The connection type capacitor C is a capacitor that connects multiple thin film capacitors, for example, Figure 4 In a state where four are arranged as shown, bus bars 21 and 23 are attached to the metal sprayed electrodes at both ends of the main body 3 via a bonding material.

[0049] The connecting capacitor C can be Figure 5 As shown, the thin film capacitors are arranged in a plane, but may also be arranged in a stacked configuration. In addition, the thin film capacitors may be arranged along the direction where the metallization electrode 4 is located, that is, along the first direction x vertical direction.

[0050] Figure 6 This is a schematic structural diagram for explaining one example of an inverter. Figure 6 Inverter D is an inverter that generates AC from DC. Figure 6 As shown in the figure, the inverter D includes a bridge circuit 31 and a capacitor 33. The bridge circuit 31 is composed of a switching element such as an IGBT (Insulatedgate Bipolar Transistor) and a diode. The capacitor 33 is arranged between the input terminals of the bridge circuit 31 to stabilize the voltage. The inverter D includes the above-mentioned film capacitor A as the capacitor 33.

[0051] A boost circuit 35 that boosts the voltage of a DC power supply is connected to the inverter D. The bridge circuit 31 is connected to a motor generator M that is a drive source.

[0052] Figure 7 is a schematic structural diagram of an electric vehicle. Figure 7 2 shows a hybrid electric vehicle (HEV) as one example of an electric vehicle.

[0053] The electric vehicle E includes a driving motor 41 , an engine 43 , a transmission mechanism 45 , an inverter 47 , a power source or a battery 49 , front wheels 51 a , and rear wheels 51 b .

[0054] The electric vehicle E has a motor 41, an engine 43, or outputs of both as a driving source. The output of the driving source is transmitted to a pair of left and right front wheels 51a via a transmission mechanism 45. A power source 49 is connected to an inverter 47, and the inverter 47 is connected to the motor 41.

[0055] In addition, if Figure 7 The electric vehicle E shown is equipped with a vehicle ECU 53 and an engine ECU 57. The vehicle ECU 53 performs overall control of the electric vehicle E. The engine ECU 57 controls the rotation speed of the engine 43 to drive the electric vehicle E. The electric vehicle E also has driving devices such as an ignition key 55 operated by a driver, etc., an accelerator pedal and a brake not shown. A driving signal corresponding to the operation of the driving device by the driver, etc. is input into the vehicle ECU 53. Based on the driving signal, the vehicle ECU 53 outputs an indication signal to the engine ECU 57, the power supply 49, and the inverter 47 as a load. In response to the indication signal, the engine ECU 57 controls the rotation speed of the engine 43 to drive the electric vehicle E.

[0056] As the inverter 47 of the electric vehicle E, an inverter D is used, that is, an inverter D including the above-mentioned film capacitor A in the capacitor section 33. In such an electric vehicle E, since the insulation resistance of the film capacitor A is not easy to decrease, even in a harsh environment such as the engine section of the electric vehicle E, the decrease in the insulation resistance of the film capacitor A can be suppressed to be small for a long period of time. As a result, in the electric vehicle E, the current control of the control device such as the ECU can be made more stable.

[0057] The inverter D of this embodiment can be applied not only to the hybrid electric vehicle (HEV) described above, but also to various power conversion application products such as electric vehicles (EV), fuel cell vehicles, electric bicycles, generators, or solar cells.

[0058] The present disclosure may be implemented in the following ways.

[0059] The film capacitor disclosed in the present invention comprises: a laminated body formed by alternately laminating at least one dielectric film including a polyarylate film and a plurality of metal vapor-deposited films;

[0060] A covering film comprising a polyester hot melt adhesive resin, wherein the covering film is laminated on two first side surfaces, and the two first side surfaces are opposite to each other in a first direction orthogonal to a lamination direction of the laminate;

[0061] The metal sprayed electrodes are stacked on two second side surfaces, and the two second side surfaces are opposed to each other in a second direction that is orthogonal to the stacking direction of the stacked body and perpendicular to the first direction.

[0062] Furthermore, a connection type capacitor of the present disclosure includes: a plurality of thin film capacitors; and a bus bar connecting the plurality of thin film capacitors; the plurality of thin film capacitors includes the above-mentioned thin film capacitor.

[0063] Furthermore, an inverter of the present disclosure includes: a bridge circuit formed of switching elements; and a capacitor connected to the bridge circuit; and the capacitor includes the above-mentioned film capacitor.

[0064] In addition, the electric vehicle disclosed herein includes: a power source, an inverter connected to the power source, a motor connected to the inverter, and wheels driven by the motor; the inverter is the inverter described above.

[0065] The thin film capacitor disclosed herein can reduce discharge of the metal vapor-deposited film caused by the gap between the cover film and the metal vapor-deposited film.

[0066] Furthermore, with the junction type capacitor disclosed in the present invention, a junction type capacitor whose insulation resistance is unlikely to decrease can be obtained.

[0067] Furthermore, with the inverter of the present disclosure, it is possible to obtain an inverter in which the insulation resistance of the film capacitor is unlikely to decrease.

[0068] Furthermore, according to the electric vehicle disclosed herein, it is possible to further stabilize the current control of a control device such as an ECU.

[0069] Although the embodiments of the present disclosure are described in detail above, the present disclosure is not limited to the above-mentioned implementation methods, and various changes and improvements can be made without departing from the gist of the present disclosure. It goes without saying that all or part of the above-mentioned embodiments can be combined within an appropriate and non-contradictory range.

[0070] Explanation of symbols:

[0071] A: film capacitor; C: junction capacitor; D: inverter; E: electric vehicle; 1, 1a, 1b: dielectric film; 2, 2a, 2b: metal vapor-deposited film; 3: main body; 3a, 3b: first surface; 3c, 3d: first side; 3e, 3f: second side; 4, 4a, 4b: metal sprayed electrode; 6, 6a, 6b: metallized film; 7, 7a, 7b: insulating blank; 12: film capacitor element; 16a, 16b: covering film; 21, 23: bus bar; 31: bridge circuit; 33: capacitor part; 35: boost circuit; 41: motor; 43: engine; 45: transmission mechanism; 47: inverter; 49: power supply; 51a: front wheel; 51b: rear wheel; 53: vehicle ECU; 55: ignition key; 57: engine ECU.

Claims

1. Film capacitors, including: A laminated body, formed by alternately laminating at least one dielectric film including a polyarylate film and a plurality of metal vapor-deposited films; A covering film comprising a polyester hot melt adhesive resin having a lower melting point than polyarylate, the covering film being laminated on two first side surfaces, the two first side surfaces being opposed in a first direction orthogonal to a lamination direction of the laminate; The metal sprayed electrodes are stacked on two second side surfaces, and the two second side surfaces are opposed to each other in a second direction that is orthogonal to the stacking direction of the stacked body and perpendicular to the first direction. 2 . The thin film capacitor according to claim 1 , wherein the cover film has a thickness of 0.1 μm to 1000 μm.

3. Connecting capacitors, including: Multiple film capacitors; and, a bus bar connecting the plurality of film capacitors; The plurality of thin film capacitors include the thin film capacitor according to claim 1 or 2.

4. Inverter, including: A bridge circuit consisting of switching elements; as well as, a capacitor connected to the bridge circuit; The capacitor unit includes the thin film capacitor according to claim 1 or 2.

5. Electric vehicles, with: power supply; an inverter connected to the power source; a motor connected to the inverter; and, wheels driven by the motor; in, The inverter is the inverter according to claim 4.

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