JP2017175867A - Power conversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power conversion device capable of securing an insulation distance, and of reducing an inductance between two conductors applied with a voltage.SOLUTION: A power conversion device 1 comprises: an inverter 3; a positive electrode connection conductor 4p electrically connected with the inverter 3, and that has a flat plate shape, and whose connection portion is folded, and whose plane is located in an opposite direction to the direction in which the connection portion is folded; a negative electrode connection conductor 4n electrically connected with the inverter 3, and applied with a voltage between the positive electrode connection conductor 4p and itself, and that has a flat plate shape, and whose connection portion is folded, and that is arranged so that a plane located in an opposite direction to the direction in which the connection portion is folded is opposed to the plane of the positive electrode connection conductor 4p; and a bolt 5 that fixes the connection portion of the positive electrode connection conductor 4p and the connection portion of the negative electrode connection conductor 4n, respectively, at such a position that insulation between the two connection conductors 4p and 4n is secured.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power conversion device.

  In general, it is known to reduce the inductance by connecting as close as possible two conductors connected to a power converter and to which a voltage is applied. When the power converter is used as a high-frequency power source, high-frequency leakage magnetic flux is prevented by reducing the inductance in this way.

  For example, it is disclosed that it is preferable to use a laminated bus bar in which DC connection conductors are formed as close as possible to each other while ensuring insulation from each other, a conductor is formed of a thin copper plate, and the conductors are insulated by an insulating film. (See Patent Document 1).

International Publication No. 2009/040933

  However, when fixing a plurality of flat connection conductors to which a voltage is applied using bolts, the bolts are inserted in a direction perpendicular to the plane of the connection conductor, such as the head or neck of the bolt. A portion will be located between the two connecting conductors. For this reason, it is necessary to secure an insulation distance between the two connection conductors in consideration of the bolts, and the connection conductors are unnecessarily wide, which hinders a reduction in inductance.

  Therefore, an object of the present invention is to provide a power conversion device that can secure an insulation distance and reduce the inductance between two conductors to which a voltage is applied.

  A power conversion device according to an aspect of the present invention is electrically connected to a power conversion circuit and the power conversion circuit. The first connection portion is bent in a flat plate shape, and the first connection portion is bent. A first conductor in which a first plane is positioned in a direction opposite to the direction and the power conversion circuit, and a voltage is applied between the first conductor and the second connection in a flat plate shape. A second conductor disposed such that a portion is bent and a second plane located in a direction opposite to the direction in which the second connection portion is bent is opposed to the first plane of the first conductor; And a fixing means for fixing the first connection portion and the second connection portion at a position where insulation between the first conductor and the second conductor is ensured.

  ADVANTAGE OF THE INVENTION According to this invention, the power converter which can ensure the insulation distance and can aim at low inductance between the two conductors to which a voltage is applied can be provided.

The block diagram which shows the structure of the power converter device which concerns on the 1st Embodiment of this invention. The block diagram which shows the structure of the state by which the positive electrode connection conductor which concerns on this embodiment, and the positive electrode terminal of a converter are connected. The block diagram which shows the structure of the power converter device which concerns on the 2nd Embodiment of this invention. The block diagram which shows the structure of the power converter device which concerns on the 3rd Embodiment of this invention. The block diagram which shows the structure of the power converter device which concerns on the 4th Embodiment of this invention.

(First embodiment)
FIG. 1 is a configuration diagram showing the configuration of the power conversion device 1 according to the first embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same part in drawing, the detailed description is abbreviate | omitted, and a different part is mainly described.

  The power conversion device 1 includes a converter 2, an inverter 3, a set of connection conductors 4 p and 4 n, four bolts 5, and four nuts 6. The power converter 1 is a BTB (back-to-back) converter in which the DC terminals of the converter 2 and the inverter 3 are connected by connecting conductors 4p and 4n.

  Converter 2 includes a power conversion circuit that converts AC power applied to the AC side into DC power. Converter 2 outputs the converted DC power to inverter 3. In addition, as long as it outputs DC power, it is not limited to the converter 2 and may be another type. For example, a generator or a battery may be used.

  Terminals 2p and 2n of converter 2 are conductors and terminals from which DC power is output. A positive electrode of a DC voltage is applied to the positive electrode terminal 2p. A negative electrode of a DC voltage is applied to the negative electrode terminal 2n. Terminals 2p and 2n have a flat plate shape, and are provided in converter 2 such that the respective wide surfaces face each other. The width Ws of the opposing surfaces of the two terminals 2p and 2n is a distance as close as possible in order to reduce the inductance within a range in which an insulation distance can be secured. The connection portions of the terminals 2p and 2n connected to the connection conductors 4p and 4n are bent at right angles to the outer sides on the opposite side and the opposite side. Holes through which the bolts 5 are passed are provided in the connection portions of the terminals 2p and 2n.

  The inverter 3 includes a power conversion circuit (inverter circuit) that converts the DC power converted by the converter 2 into AC power for supplying the load. The AC power output from the inverter 3 may be a single-phase AC or a three-phase AC. Terminals 3p and 3n of the inverter 3 are conductors and are terminals to which DC power output from the converter 2 is input. A positive electrode having a DC voltage is applied to the positive electrode terminal 3p. A negative electrode of a DC voltage is applied to the negative electrode terminal 3n. Note that the terminals 3p and 3n of the inverter 3 are provided in the same manner as the terminals 2p and 2n of the converter 2, and thus description thereof is omitted.

  A DC voltage output from the converter 2 and input to the inverter 3 is applied to the connection conductors (DC conductors) 4p and 4n. A positive electrode of a DC voltage is applied to the positive electrode connection conductor 4p. A negative electrode of a DC voltage is applied to the negative electrode connection conductor 4n. The connection conductors 4p and 4n have a long and thin flat plate shape, and have both ends bent at right angles in the same direction. Both ends of the connection conductors 4p and 4n are bent so as to face outward while being connected to the converter 2 or the inverter 3, respectively. The bent portions are connection portions connected to the terminals 2p and 2n of the converter 2 or the terminals 3p and 3n of the inverter 3. Thereby, the planes of the main body portions (portions other than the connection portions) of the connection conductors 4p and 4n are positioned in the direction opposite to the direction in which the connection portions of the connection conductors 4p and 4n are bent. In each connection portion of the connection conductors 4p and 4n, holes through which the bolts 5 for connecting to the terminals 2p and 2n of the converter 2 or the terminals 3p and 3n of the inverter 3 are passed, respectively. The connection conductors 4p and 4n are made of a material having excellent conductivity such as copper, and are not subjected to an electrical insulation process such as a lamination process for covering the surface with an insulating sheet.

  The four pairs of bolts 5 and nuts 6 electrically connect and fix the connection conductors 4p and 4n and the terminals 2p and 2n of the converter 2 or the terminals 3p and 3n of the inverter 3, respectively. The bolt 5 may be of a type that does not require a nut.

  FIG. 2 is a configuration diagram showing a configuration in a state where the positive electrode connection conductor 4p and the positive electrode terminal 2p of the converter 2 according to the present embodiment are connected. Since the connection methods of the connection conductors 4p and 4n and the terminals 2p and 2n of the converter 2 or the terminals 3p and 3n of the inverter 3 are the same, here, the positive connection conductor 4p and the positive terminal 2p of the converter 2 Will be described, and other connection methods will be omitted.

  The connection part bent to the outside of the positive electrode connection conductor 4p and the connection part bent to the outside of the positive electrode terminal 2p of the converter 2 are brought into close contact with each other so that the holes for passing the bolts 5 are overlapped. Next, the bolt 5 is passed through the hole in the connection portion of the positive electrode connection conductor 4 p and the hole in the connection portion of the positive electrode terminal 2 p of the converter 2, and tightened with the nut 6. Thereby, the positive electrode connection conductor 4p and the positive electrode terminal 2p of the converter 2 are electrically connected.

  In the state where the connection conductors 4p and 4n are attached to the power conversion device 1, both ends of each of the connection conductors 4p and 4n face outward, and within the range of maintaining an insulation distance that can insulate the applied DC voltage, It arrange | positions so that the plane of a part may oppose as close as possible. The closer the distance Ws between the two opposing surfaces, the lower the inductance.

  According to the present embodiment, the two connection portions are formed by bending the connection portions at both ends of the two flat connection conductors 4p and 4n in a state of being attached to the converter 2 or the inverter 3. It can fix with the volt | bolt 5 on the outer side between the conductors 4p and 4n.

  Accordingly, since the bolt 5 is not positioned between the two connection conductors 4p and 4n, the width Ws between the two connection conductors 4p and 4n can be made as close as possible within a range that maintains the insulation distance. Therefore, the inductance between the two connection conductors 4p and 4n can be reduced.

  Further, since the insulation distance between the two connection conductors 4p and 4n is maintained, it is not necessary to perform an insulation process such as laminating on the connection conductors 4p and 4n. Therefore, the manufacturing cost of the connection conductors 4p and 4n and the power converter 1 can be suppressed.

  For example, when the connection portions of the connection conductors 4p and 4n and the connection portions of the other conductors are fixed by inserting the bolts 5 from the opposing surface sides (inside) of the connection conductors 4p and 4n, respectively, at least the connection conductors 4p and 4n. Is required to be at least two times (twice) the height of the head of the bolt 5. Here, the height of the head of the bolt 5 cannot be changed to an arbitrary height because it is often determined by a standard or the like in consideration of strength such as tensile strength. On the other hand, in the present embodiment, since the bolt 5 is not located between the connection conductors 4p and 4n, the distance between the connection conductors 4p and 4n is less than twice the height of the head of the bolt 5. Thus, the inductance can be reduced.

  Further, when the power conversion device 1 is used as a high-frequency power source, the connection conductors 4p and 4n can form two connection conductors 4p and 4n serving as a reciprocating path between the current and the return in order to reduce the leakage magnetic flux to the periphery. It is effective to adhere as much as possible. In such a case, it is possible to realize a high-frequency power source with less leakage magnetic flux by bringing the two connection conductors 4p and 4n closer without considering the bolt 5.

(Second Embodiment)
FIG. 3 is a configuration diagram showing a configuration of a power conversion device 1A according to the second embodiment of the present invention.

  1 A of power converters are the power converters 1 which concern on 1st Embodiment shown in FIG. 1, and provided the insulator 7 between the connection conductors 4p and 4n. The width Wsa between the two connection conductors 4p and 4n is narrower than the width Ws according to the first embodiment. Further, the width between the terminals 2p and 2n of the converter 2 and the width between the terminals 3p and 3n of the inverter 3 are narrower than those of the first embodiment, similarly to the width Wsa between the connection conductors 4p and 4n. About another point, 1 A of power converter devices are the same as that of the power converter device 1 which concerns on 1st Embodiment.

  The insulator 7 is an insulator for insulating the two connection conductors 4p and 4n to which a DC voltage is applied. The insulator 7 may be attached in any way as long as it is located between the two connecting conductors 4p and 4n. For example, the insulator 7 may be attached to one of the two connection conductors 4p and 4n, or may be attached to both of them, or may be positioned between the connection conductors 4p and 4n by a support member or the like. You just need to be supported.

  According to the present embodiment, in addition to the operational effects of the first embodiment, the following operational effects can be obtained.

  By providing the insulator 7 between the two connection conductors 4p and 4n, the two connection conductors 4p and 4n can be reliably insulated. Further, by providing the insulator 7, the space insulation distance which is the minimum distance required to secure insulation without providing the insulator 7 or the like between the two connection conductors 4p and 4n. Can be made narrower. Thereby, the inductance can be further reduced.

(Third embodiment)
FIG. 4 is a configuration diagram showing a configuration of a power conversion device 1B according to the third embodiment of the present invention.

  The power conversion device 1B includes an inverter 3, a set of connection conductors 4u and 4v, four bolts 5, and four nuts 6. The power conversion device 1 </ b> B supplies single-phase AC power to the AC load 8.

  The inverter 3 includes a power conversion circuit (inverter circuit) that converts input DC power into single-phase AC power to be supplied to the AC load 8. Terminals 3u and 3v of the inverter 3 are conductors and terminals from which single-phase AC power is output. The U phase of AC voltage is applied to the U phase terminal 3u. The V phase of AC voltage is applied to the V phase terminal 3v. In other respects, the terminals 3u and 3v of the inverter 3 are the same as the terminals 2p and 2n of the converter 2 according to the first embodiment.

  Terminals 8u and 8v of the AC load 8 are conductors and are terminals to which AC power output from the inverter 3 is input. The U phase of the AC voltage is applied to the U phase terminal 8u. The V phase of the AC voltage is applied to the V phase terminal 8v. Since the terminals 8u and 8v of the AC load 8 are provided in the same manner as the terminals 3u and 3v of the inverter 3, description thereof is omitted.

  Since the connection conductors (AC conductors) 4u and 4v are configured in the same manner as the connection conductors (DC conductors) 4p and 4n according to the first embodiment, differences will be mainly described. The U phase of AC voltage is applied to the U phase connection conductor 4u. The V phase of the AC voltage is applied to the V phase connection conductor 4v. In a state in which the connection conductors 4u and 4v are attached to the power conversion device 1B, as in the case of the connection conductors 4p and 4n according to the first embodiment, within a range that maintains an insulation distance that can insulate the applied AC voltage. The two connecting conductors 4u and 4v are arranged so that the opposing planes are as close as possible. The closer the distance Wsb between the two opposing surfaces, the lower the inductance.

  The connection method of the terminals 3u, 3v of the inverter 3 or the terminals 8u, 8v of the AC load 8 and the connection conductors 4u, 4v by the bolt 5 and the nut 6 is the same as the connection method described in the first embodiment shown in FIG. It is.

  According to the present embodiment, by using the connection conductors 4u and 4v as alternating current conductors, it is possible to obtain the same functions and effects as those of the first embodiment.

(Fourth embodiment)
FIG. 5 is a configuration diagram showing a configuration of a power conversion device 1C according to the fourth embodiment of the present invention.

  1 C of power converters are the power converters 1B which concern on 3rd Embodiment shown in FIG. 4, and provide the insulator 7 which concerns on 2nd Embodiment between the connection conductors 4u and 4v. The width Wsc between the two connection conductors 4u and 4v is narrower than the width Wsb according to the third embodiment. Further, the width between the terminals 3u and 3v of the inverter 3 and the width between the terminals 8u and 8v of the AC load 8 are narrower than those of the third embodiment, similarly to the width Wsc between the connection conductors 4u and 4v. About other points, 1C of power converters are the same as that of power converter 1B concerning a 3rd embodiment.

  According to the present embodiment, in addition to the functions and effects of the third embodiment, the following functions and effects can be obtained.

  By providing the insulator 7 between the two connection conductors 4u and 4v, the two connection conductors 4u and 4v can be reliably insulated. Further, by providing the insulator 7, the width Wsc between the two connection conductors 4u and 4v can be made narrower than the space insulation distance, as in the second embodiment. Thereby, the inductance can be further reduced.

  In addition, although 1st Embodiment and 3rd Embodiment were demonstrated separately, you may combine. Specifically, the connection conductors (DC conductors) 4p and 4n according to the first embodiment are connected to the DC terminals 3p and 3n of the inverter 3, and the AC terminals 3u and 3v of the inverter 3 according to the third embodiment. This can be realized by connecting the connection conductors (AC conductors) 4u and 4v. Similarly, the second embodiment may be combined with the fourth embodiment, the first embodiment may be combined with the fourth embodiment, or the second embodiment may be combined with the third embodiment. .

  In each embodiment, one connection conductor 4p, 4n, 4u, and 4v is provided for each polarity or phase to be applied, but two or more may be provided. For example, the connecting portions of the plurality of positive electrode connection conductors 4p may be connected in series by bolts 5 and nuts 6 to extend the positive electrode connection conductor 4p. The same applies to the other connection conductors 4n, 4u, 4v.

  In each embodiment, the connection portions at both ends of the connection conductors 4p, 4n, 4u, and 4v are bent outward. However, only the connection portion at one end may be bent outward. At least in the connection portion that is bent outward, the bolt 5 is not located between the connection conductors 4p, 4n, 4u, and 4v to which a voltage is applied. Therefore, the same effects as those of the embodiments can be obtained.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

  DESCRIPTION OF SYMBOLS 1 ... Power converter device, 2 ... Converter, 3 ... Inverter, 4p, 4n ... Connection conductor, 5 ... Bolt, 6 ... Nut.

Claims (5)

A power conversion circuit;
A first conductor that is electrically connected to the power conversion circuit, has a flat plate shape, the first connection portion is bent, and a first plane is located in a direction opposite to the direction in which the first connection portion is bent; ,
Electrically connected to the power conversion circuit, a voltage is applied between the first conductor, the second connection portion is bent in a flat plate shape, and is opposite to the direction in which the second connection portion is bent. A second conductor disposed such that a second plane located in a direction faces the first plane of the first conductor;
A fixing means for fixing the first connection portion and the second connection portion, respectively, at a position where insulation between the first conductor and the second conductor is ensured. Power conversion device. The fixing means is a bolt;
2. The power conversion device according to claim 1, wherein a distance between the first conductor and the second conductor is less than twice a height of a head portion of the bolt. The power converter according to claim 1, wherein a DC voltage is applied between the first conductor and the second conductor. The power converter according to claim 1, wherein an alternating voltage is applied between the first conductor and the second conductor. The power converter according to any one of claims 1 to 4, further comprising an insulator provided between the first conductor and the second conductor.

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