Filter unit and power conversion device

Abstract

A filter unit (100) comprises: a cylindrical filter core (7) into which are inserted busbars (9) such as a positive electrode power supply-side conductor and a negative electrode power supply-side conductor of a power conversion device; a resin housing (6) that holds the filter core; and a noise removal capacitor unit (10) electrically connected to a busbar, wherein the resin housing has a terminal block part (30) to which the busbar is connected, the terminal block part is located on the outside of the filter core in the radial direction, and is disposed so that at least a part thereof overlaps the filter core when viewed from the outside in the radial direction.

Description

Filter unit and power conversion device

[0001] The present invention relates to a filter unit and a power conversion device.

[0002] For example, Patent Document 1 discloses a power conversion device that reduces the inductance of a noise filter circuit to increase output. The power conversion device disclosed in Patent Document 1 includes a power supply conductor connected to a high-voltage battery and a core member through which the power supply conductor passes. The core member suppresses electromagnetic noise by absorbing fluctuations in the current flowing through the power supply conductor.

[0003] Patent No. 6838775

[0004] The power conversion device disclosed in Patent Document 1 includes bus bars such as a positive power supply conductor and a negative power supply conductor. In the power conversion device disclosed in Patent Document 1, the positive power supply conductor and the negative power supply conductor are inserted into an annular core member. These bus bars, such as the positive power supply conductor and the negative power supply conductor, are connected to battery terminals. Although not disclosed in Patent Document 1, these bus bars, such as the positive power supply conductor and the negative power supply conductor, are fastened to a terminal block and connected to the battery terminals via the terminal block. Therefore, the power conversion device of Patent Document 1 requires a terminal block to be provided separately from the resin member that holds the core member, and the terminal block occupies a portion of the interior of the case of the power conversion device.

[0005] The present invention has been made in consideration of the above-described problems, and makes it possible to reduce the number of terminal blocks to which the bus bars inserted into the filter core are fixed in a power conversion device having bus bars inserted into a cylindrical filter core.

[0006] The present invention employs the following configuration as a means for solving the above problems.

[0007] A first aspect of the present invention employs a configuration including a cylindrical filter core through which a bus bar is inserted, a resin housing that holds the filter core, and a noise-removal capacitor unit electrically connected to the bus bar, wherein the resin housing has a terminal block portion to which the bus bar is connected, the terminal block portion being located radially outward from the filter core and arranged so that at least a portion of the terminal block portion overlaps the filter core when viewed from the radial outside.

[0008] A second aspect of the present invention is a power conversion device according to the first aspect, which includes a power terminal connected to a battery and converts power passing through the power terminal, and which employs a configuration in which the power terminal includes a filter unit according to the first aspect that suppresses electromagnetic noise.

[0009] In the present invention, the resin housing that holds the filter core has a terminal block portion to which the bus bar is connected. Therefore, the present invention eliminates the need to provide a terminal block separately from the resin housing. Therefore, according to the present invention, in a power conversion device having bus bars that are inserted into a cylindrical filter core, it is possible to reduce the number of terminal blocks to which the bus bars are fixed.

[0010] FIG. 1 is a circuit diagram showing a schematic electrical configuration of a power conversion device according to one embodiment of the present invention. FIG. 2 is an exploded perspective view showing a schematic structural configuration of a power conversion device according to one embodiment of the present invention. FIG. 3 is a schematic perspective view of a power terminal provided in a power conversion device according to one embodiment of the present invention. FIG. 4 is a schematic exploded perspective view of a power terminal provided in a power conversion device according to one embodiment of the present invention. FIG. 5 is a schematic perspective view showing a resin housing of a power terminal provided in a power conversion device according to one embodiment of the present invention. FIG. 6 is a schematic perspective view including a resin housing showing a modified example of a power terminal provided in a power conversion device according to one embodiment of the present invention. FIG. 7 is a schematic circuit diagram of a power terminal provided in a power conversion device according to one embodiment of the present invention.

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a filter unit and a power conversion device according to the present invention will be described with reference to the drawings.

[0012] 1 is a circuit diagram showing a schematic electrical configuration of a power conversion device 1 of this embodiment. The power conversion device 1 of this embodiment is mounted on a vehicle such as an electric automobile and is provided between a motor M and a battery B. The power conversion device 1 of this embodiment performs power conversion between the motor M and the battery B. For example, the power conversion device 1 of this embodiment converts DC power supplied from the battery B into three-phase AC power and supplies it to the motor M. The power conversion device 1 also converts regenerative power (AC power) from the motor M into DC power and supplies it to the battery B.

[0013] As shown in Fig. 1 , the power conversion device 1 of this embodiment includes a power conversion circuit H. As described above, the power conversion circuit H converts DC power into AC power. The power conversion circuit H also converts AC power into DC power. The power conversion circuit H includes a capacitor C, an inverter circuit E, and a noise filter F. The power conversion device 1 may also include, for example, a step-up / step-down converter or a DC / DC converter (not shown).

[0014] The power conversion device 1 of this embodiment also includes a conductive line BU through which power is conducted. For example, the power conversion device 1 of this embodiment includes a conductive line BU that connects the inverter circuit E and the battery B, and a conductive line BU that connects the inverter circuit E and the motor M.

[0015] As shown in FIG. 1 , the inverter circuit E includes three legs R corresponding to the respective phases of the motor M. Each leg R includes an upper arm HA and a lower arm LA. The upper arm HA is connected to the positive electrode side of a battery B via a conductive line BU. The lower arm LA is connected to the negative electrode side of the battery B via a conductive line BU. The upper arm HA and the lower arm LA are connected in series. An output terminal that connects the legs R and the motor M is connected between the upper arm HA and the lower arm LA.

[0016] As shown in FIG. 1 , the power conversion device 1 of this embodiment includes power devices D (semiconductor substrates) corresponding to each leg R. That is, in this embodiment, the power conversion device 1 includes three power devices D. Each power device D includes a power transistor corresponding to the upper arm HA and a power transistor corresponding to the lower arm. That is, in this embodiment, each power device D includes two power transistors. Each of these power transistors is formed using a plurality of semiconductor elements. Such semiconductor elements are, for example, IGBTs (Insulated Gate Bipolar Transistors). Furthermore, the semiconductor elements may be semiconductor elements using SiC (silicon carbide) or GaN (gallium nitride).

[0017] 1, the power conversion device 1 of this embodiment is provided with a noise filter F surrounding the conductive line BU connected to the positive electrode side of the battery B and the conductive line BU connected to the negative electrode side of the battery B. This noise filter F suppresses changes in the current flowing through the conductive line BU, thereby suppressing the generation of electromagnetic noise.

[0018] Fig. 2 is an exploded perspective view showing a schematic structural configuration of the power conversion device 1 of this embodiment. As shown in Fig. 2, the power conversion device 1 of this embodiment includes an inverter case 2, an intelligent power module 3, a capacitor unit 4, and a power supply terminal 5. Note that the power conversion device 1 may also include other components such as a reactor unit forming a step-up / step-down circuit and a DC-DC converter unit forming a DC-DC converter.

[0019] The inverter case 2 is a case that houses the intelligent power module 3, the capacitor unit 4, the power terminals 5, etc., and includes a center plate 2a and a case cover 2b. The center plate 2a and the case cover 2b are formed as separate parts that can be detached from each other. Note that FIG. 2 illustrates a state in which the case cover 2b is separated above the center plate 2a. However, the installation posture of the power conversion device 1 is not particularly limited. In other words, the power conversion device 1 may be mounted on a vehicle so that the case cover 2b is located to the side of the center plate 2a.

[0020] The central plate 2a has a bottom wall to which the intelligent power modules 3, capacitor units 4, and power terminals 5 are fixed, and side walls that surround the intelligent power modules 3, capacitor units 4, and power terminals 5. In other words, the central plate 2a is formed in the shape of a container that is open on the case cover 2b side. Such central plate 2a is provided with water channels as necessary, and is formed to be able to guide the coolant that cools the intelligent power modules 3, capacitor units 4, and power terminals 5.

[0021] The case cover 2b is fixed to the center plate 2a and covers the intelligent power modules 3 and the capacitor units 4. That is, the intelligent power modules 3 and the capacitor units 4 are exposed when the case cover 2b is detached from the center plate 2a.

[0022] Such an inverter case 2 is fixed to, for example, a housing (not shown) that covers the motor M or a gear case that houses a gear that transmits power generated by the motor M to the outside. In such a case, for example, the center plate 2a is fastened to the motor housing or the gear case using a bolt (not shown) or the like. Note that if the housing that covers the motor M has a space for accommodating the power conversion device 1, the case cover 2b may be omitted.

[0023] The inverter case 2 also holds a conductive line BU (see FIG. 1) that connects the power supply terminal 5 to the intelligent power module 3 and the capacitor unit 4, and bus bars that form part of the conductive line BU (see FIG. 1) (not shown) that connects the intelligent power module 3 to the motor M. Note that these bus bars are omitted in FIG. 1.

[0024] The intelligent power module 3 includes a power module 3a and a substrate unit 3b. The power module 3a is a module provided with a plurality of power devices D, which will be described later. In other words, the power module 3a forms an inverter circuit E with the plurality of power devices D.

[0025] The board unit 3b is stacked on the power module 3a. This board unit 3b includes, for example, a gate driver board and an ECU (Electronic Control Unit) board. The gate driver board is a board provided with a gate driver that generates a drive signal for the inverter circuit E formed by the power module 3a. The ECU board is a board provided with an ECU that controls the gate driver board.

[0026] The capacitor unit 4 is a unit that houses a capacitor element therein. The capacitor unit 4 is connected to the power module 3a. The capacitor unit 4 is also connected to the power terminal 5 via a bus bar (not shown). The capacitor unit 4 forms the capacitor C shown in FIG. 1.

[0027] The power supply terminal 5 is a component for connecting to the battery B of the power conversion device 1 of this embodiment. A terminal portion of a harness (not shown) connected to the battery B is inserted into the inverter case 2. The power supply terminal 5 is connected to the battery B by fastening to the harness.

[0028] Fig. 3 is a schematic perspective view of the power terminal 5. Fig. 4 is a schematic exploded perspective view of the power terminal 5. As shown in these figures, the power terminal 5 of this embodiment includes a resin housing 6, a filter core 7, a core cover 8, a bus bar 9, a noise removal capacitor unit 10, a conductive member 11, and a frame ground connection member 12.

[0029] 5 is a schematic perspective view of the resin housing 6. As shown in FIGS. 3 to 5, the resin housing 6 holds the filter core 7 and is a member formed mainly of resin. In this embodiment, the resin housing 6 also functions as a terminal block to which the bus bar 9 is fastened. In this embodiment, the resin housing 6 has a core holding portion 20, a terminal block portion 30, and a fixing portion 40.

[0030] The core holding portion 20 is a portion that houses the cylindrical filter core 7, and houses the filter core 7 arranged so that its axial direction (the direction in which the bus bar 9 is inserted) is perpendicular to the up-down direction. That is, the core holding portion 20 is formed in a hollow cylindrical shape. The core holding portion 20 is formed so that one end in the axial direction (the direction in which the bus bar 9 is inserted) is a closed end and the other end is an open end.

[0031] The installation orientation of the power terminal is not particularly limited, but for the sake of convenience, the direction in the axial direction where the closed end of the core holding portion 20 is located is referred to as the front, and the direction in the axial direction where the open end of the core holding portion 20 is located is referred to as the rear.

[0032] In other words, the core holding portion 20 is formed so that the front side is a closed end and the rear side is an open end. With the core cover 8 removed, the filter core 7 can be inserted and removed from the core holding portion 20 from the rear side.

[0033] The terminal block 30 is integrated with the core holding portion 20 and is located outside the core holding portion 20 in the radial direction of the filter core 7 (hereinafter simply referred to as the radial direction). In other words, the terminal block 30 is located outside the radial direction of the core holding portion 20. In this embodiment, the terminal block 30 is located mainly above the core holding portion 20.

[0034] The terminal block 30 also has a plurality of fastening nuts 31. These fastening nuts 31 are nuts onto which fastening bolts 13 for fastening the bus bar 9 or the conductive member 11 to the terminal block 30 are screwed, and are provided so as to be exposed on the front surface of the terminal block 30. In this embodiment, these fastening nuts 31 are arranged with their central openings (openings with female threads formed on their inner circumferential surfaces) facing forward (the direction in which the bus bar 9 is inserted into the filter core 7). In other words, the fastening bolts 13 can be screwed onto these fastening nuts 31 from the front.

[0035] In this embodiment, the terminal block 30 has four fastening nuts 31. Two of these four fastening nuts 31 are threadedly engaged with fastening bolts 13 for fastening the bus bar 9. In the following description, the fastening nuts 31 onto which the fastening bolts 13 for fastening the bus bar 9 are threadedly engaged will be referred to as bus bar fastening nuts 32.

[0036] Of the four fastening nuts 31, two fastening nuts 31 excluding the bus bar fastening nut 32 are threaded with fastening bolts 13 for fastening the conductive members 11. In the following description, the fastening nuts 31 onto which the fastening bolts 13 for fastening the conductive members 11 are threaded are referred to as conductive member fastening nuts 33.

[0037] The bus bar fastening nuts 32 are disposed above the filter core 7 and above the conductive member fastening nuts 33. The conductive member fastening nuts 33 are disposed below the bus bar fastening nuts 32 and to the side of the filter core 7.

[0038] Furthermore, a plurality of board fastening nuts 34 are provided on the upper surface of the terminal block 30, into which fastening bolts 14 are threadedly engaged to fasten the noise removal capacitor unit 10 to the terminal block 30. In this embodiment, three board fastening nuts 34 are provided.

[0039] Such terminal block portion 30 is located radially outside of the filter core 7 and is disposed so that, when viewed from the radial outside, at least a portion of it overlaps with the filter core 7. In this embodiment, the terminal block portion 30 is formed to a size such that the entire filter core 7 is hidden by the terminal block portion 30 when viewed from above, i.e., the radial outside.

[0040] The fixing portion 40 is a flange-shaped portion located at the bottom of the resin housing 6, below the terminal block portion 30. The fixing portion 40 is provided so as to protrude radially outward from the core holding portion 20.

[0041] The fixing portion 40 is fastened to the inverter case 2 via bolts (not shown) or the like. As shown in Fig. 5, the fixing portion 40 is provided with a plurality of cylindrical collars 41 through which bolts (not shown) are inserted. These collars 41 are provided so as to penetrate in the vertical direction.

[0042] The filter core 7 is made of a magnetic material and formed in a cylindrical shape. When the filter core 7 is housed in the core holding portion 20 of the terminal block 30, the filter core 7 is arranged so that its axis overlaps with the axis of the core holding portion 20.

[0043] The core cover 8 is formed in an annular shape so as to close the open end of the core holding portion 20. The core cover 8 is fixed to the core holding portion 20 and the filter core 7 so as to close the rear open end of the core holding portion 20.

[0044] The bus bar 9 is connected to the battery B and is a plate-shaped transmission path through which DC power flows. Two bus bars 9 are provided. One bus bar 9 is connected to the positive electrode side of the battery B. The other bus bar 9 is connected to the negative electrode side of the battery B. These bus bars 9 are arranged in parallel with a certain gap between them.

[0045] Such bus bars 9 form part of the conductive lines BU shown in Fig. 1. In other words, these bus bars 9 are DC transmission conductors that connect the battery B and the power conversion circuit H.

[0046] 3 and 4, each bus bar 9 has a horizontal portion 9a that passes through the filter core 7 and a vertical portion 9b that extends upward from the front end of the horizontal portion 9a. A bolt insertion hole 9b1 that penetrates in the front-to-rear direction is provided at the upper end of the vertical portion 9b.

[0047] When viewed from the front, each bus bar 9 is disposed such that its bolt insertion hole 9b1 overlaps with a bus bar fastening nut 32. The vertical portion 9b of each bus bar 9 is fastened to the terminal block portion 30 (i.e., the resin housing 6) by a fastening bolt 13 inserted into the bolt insertion hole 9b1.

[0048] 3 and other figures, the vertical portion 9b is fastened to the terminal block portion 30 in a state where it is exposed on the front surface of the power terminal 5 of this embodiment. As described above, the terminal portion of the harness (not shown) connected to the battery B is inserted inside the inverter case 2.

[0049] The terminal portion of such a harness is arranged from below to above so as to be parallel to the vertical portion 9b, and is further fastened to the vertical portion 9b exposed on the front surface of the power terminal 5, thereby electrically connecting the battery B to the bus bar 9. The terminal portion of such a harness is fastened together with the vertical portion 9b to the terminal block portion 30 by fastening bolts 13.

[0050] Each bus bar 9 also has branch pieces 9c protruding laterally from the vertical portion 9b. Each branch piece 9c is provided with a bolt insertion hole 9c1 penetrating in the front-to-rear direction. When viewed from the front, each bus bar 9 is positioned such that the bolt insertion hole 9c1 overlaps with a conductive member fastening nut 33. In such a bus bar 9, the branch pieces 9c are fastened to the terminal block portion 30 (i.e., the resin housing 6) by fastening bolts 13 inserted into the bolt insertion holes 9c1.

[0051] In order to maintain the distance between the two bus bars 9, a bus bar cover may be provided between the bus bars 9. The bus bar cover is made of an insulating material, and positions the bus bars 9 and prevents the bus bars 9 from shorting out.

[0052] The noise-removal capacitor unit 10 is electrically connected to the bus bar 9. Specifically, the noise-removal capacitor unit 10 is connected to the bus bar 9 via a conductive member 11. The noise-removal capacitor unit 10 has a circuit board 10a and a plurality of ceramic capacitors 10b mounted on the circuit board 10a.

[0053] The noise elimination capacitor unit 10 is fastened to the terminal block 30 (i.e., the resin housing 6) by fastening bolts 14 that are threaded into board fastening nuts 34 of the terminal block 30. The noise elimination capacitor unit 10 is placed on the upper surface of the terminal block 30 and is located radially outward of the filter core 7.

[0054] Furthermore, when viewed from the outside in the radial direction, the noise removal capacitor unit 10 is arranged so that at least a portion of the noise removal capacitor unit 10 overlaps with the filter core 7. In this embodiment, the noise removal capacitor unit 10 is arranged so that the entire noise removal capacitor unit 10 overlaps with the filter core 7 when viewed from the outside in the radial direction.

[0055] The conductive member 11 is a wiring member that connects the noise removal capacitor unit 10 and the bus bar 9. In this embodiment, a conductive member 11 is provided for each bus bar 9. That is, two conductive members 11 are provided. One end of one conductive member 11 is connected to a branch piece 9c of the bus bar 9 that is connected to the positive electrode side of the battery B. One end of one conductive member 11 is fastened together with the branch piece 9c to the terminal block 30 by a fastening bolt 13.

[0056] The other end of one conductive member 11 is connected to the noise removal capacitor unit 10. The other end of one conductive member 11 is fastened together with the circuit board 10a to the terminal block 30 by a fastening bolt 14.

[0057] One end of the other conductive member 11 is connected to a branch piece 9c of the bus bar 9 connected to the negative terminal side of the battery B. One end of the other conductive member 11 is fastened together with the branch piece 9c to the terminal block 30 by a fastening bolt 13.

[0058] The other end of the other conductive member 11 is connected to the noise removal capacitor unit 10. The other end of the other conductive member 11 is fastened together with the circuit board 10a to the terminal block 30 by a fastening bolt 14.

[0059] The frame ground connection member 12 is a wiring member for electrically connecting the noise removal capacitor unit 10 to the frame ground. One end of the frame ground connection member 12 is connected to, for example, the inverter case 2 by a bolt (not shown). The other end of the frame ground connection member 12 is fastened together with the circuit board 10a to the terminal block 30 by a fastening bolt 14.

[0060] As shown in Fig. 3 and other figures, the conductive member 11 and the frame ground connection member 12 are arranged along the side surfaces of the terminal block 30. However, as shown in Fig. 6, the conductive member 11 can also be arranged along the front and top surfaces of the terminal block 30.

[0061] In such a case, one end of the conductive member 11 may be fastened together with the vertical portion 9b of the bus bar 9 to the terminal block portion 30 by a fastening bolt 13 threaded into a bus bar fastening nut 32. This allows a configuration without the conductive member fastening nut 33, as shown in FIG. 6 . Also, the number of fastening bolts 13 can be reduced from four to two. Furthermore, the conductive member 11 can be shortened.

[0062] 7 is a schematic circuit diagram of the power supply terminal 5. As shown in this figure, in the power supply terminal 5, one conductive member 11 is connected to the bus bar 9 connected to the positive electrode side (P side) of battery B. The other conductive member 11 is connected to the bus bar 9 connected to the negative electrode side (N side) of battery B. Ceramic capacitors 10b are connected to these conductive members 11. Frame ground connection members 12 are also connected to these ceramic capacitors 10b.

[0063] When assembling the power conversion device 1 of this embodiment, the terminal portion of the harness connected to the battery B is fastened to the terminal block portion 30 together with the bus bar 9 using the fastening bolts 13. This electrically connects the battery B to the bus bar 9. In addition, since the noise removal capacitor unit 10 is connected to the bus bar 9, it is possible to remove noise components from the current flowing through the bus bar 9.

[0064] Of the resin housing 6, filter core 7, core cover 8, bus bar 9, noise elimination capacitor unit 10, conductive member 11, and frame ground connection member 12 included in the power terminal 5 of this embodiment, the resin housing 6, filter core 7, core cover 8, noise elimination capacitor unit 10, conductive member 11, and frame ground connection member 12, excluding the bus bar 9, form a filter unit 100. In other words, the power terminal 5 of this embodiment includes the filter unit 100 and the bus bar 9.

[0065] The filter unit 100 of this embodiment includes a filter core 7, a resin housing 6, and a noise removal capacitor unit 10. The filter core 7 is formed in a cylindrical shape and has a bus bar 9 inserted therethrough. The resin housing 6 holds the filter core 7. The noise removal capacitor unit 10 is electrically connected to the bus bar 9. The resin housing 6 also has a terminal block 30 to which the bus bar 9 is connected. The terminal block 30 is located radially outward of the filter core 7 and is arranged so that at least a portion of the terminal block 30 overlaps with the filter core 7 when viewed from the radial outside.

[0066] In the filter unit 100 of this embodiment, the resin housing 6 that holds the filter core 7 has a terminal block portion 30 to which the bus bar 9 is connected. Therefore, the filter unit 100 of this embodiment does not need to provide the terminal block portion 30 separately from the resin housing 6. Therefore, according to the filter unit 100 of this embodiment, in a power conversion device that has the bus bar 9 that is inserted into the cylindrical filter core 7, it is possible to eliminate the need for a terminal block to which the bus bar 9 is fixed.

[0067] According to the filter unit 100 of this embodiment, there is no need to provide a terminal block separately from the resin housing 6, and therefore the terminal block does not occupy part of the interior of the inverter case 2, thereby making it possible to reduce the size and weight of the power conversion device 1. For example, compared to when the terminal block is provided separately from the resin housing 6, the filter unit 100 of this embodiment can reduce the weight by approximately 5%.

[0068] Furthermore, the terminal block 30 provided on the resin housing 6 is arranged to overlap the filter core 7 when viewed from above (radially outward). This reduces the area inside the inverter case 2 that is occupied only by the filter core 7 and the terminal block 30 in a plan view, thereby reducing the size of the power conversion device 1 in a plan view. For example, by arranging the filter core 7 and the terminal block 30 to overlap when viewed from above, as in this embodiment, the area occupied by the filter unit 100 can be reduced by approximately 20% compared to when the filter core 7 and the terminal block 30 do not overlap when viewed from above.

[0069] Furthermore, in the filter unit 100 of this embodiment, the filter core 7 can be housed in the resin housing 6. Therefore, for example, there is no need to house the filter core 7 in a separate cover and then adhere this cover to the resin housing 6. Therefore, with the filter unit 100 of this embodiment, the assembly process can be simplified and assembly costs can be reduced.

[0070] Furthermore, in the filter unit 100 of this embodiment, the terminal block 30 has a bus bar fastening nut 32 onto which the fastening bolt 13 can be threaded to fasten the bus bar 9 to the terminal block 30. The bus bar fastening nut 32 is disposed with its central opening facing the insertion direction of the bus bar 9 in the filter core 7.

[0071] 3 , the filter unit 100 of this embodiment allows the bus bars 9 to extend vertically (radially) and be fastened to the terminal block 30 using fastening bolts 13. This allows the terminal portions of the harness connected to the battery B to also be disposed extending vertically (radially) like the bus bars 9. This reduces the area of ​​the harness terminal portions and the bus bars 9 when viewed from above, and makes it possible to reduce the area occupied by the harness terminal portions and the bus bars 9 inside the inverter case 2 in a plan view.

[0072] In the filter unit 100 of this embodiment, the noise removal capacitor unit 10 is located radially outside the filter core 7 and is arranged so that at least a portion of the noise removal capacitor unit 10 overlaps with the filter core 7 when viewed from the radial outside.

[0073] According to the filter unit 100 of this embodiment, the area occupied by only the noise removal capacitor unit 10 inside the inverter case 2 in plan view can be reduced, and the size of the power conversion device 1 in plan view can be reduced.

[0074] The filter unit 100 of this embodiment also includes a conductive member 11 that connects the noise removal capacitor unit 10 and the bus bar 9. The conductive member 11 is separate from the resin housing 6.

[0075] According to the filter unit 100 of this embodiment, it is not necessary to mold the conductive member 11 into the resin housing 6. Therefore, the resin housing 6 can be molded without being affected by the conductive member 11.

[0076] 6, the filter unit 100 of this embodiment can also employ a configuration in which the conductive member 11 is fastened together with the bus bar 9 to the resin housing 6. In such a case, the filter unit 100 of this embodiment can be configured without the conductive member fastening nut 33, as described above. The number of fastening bolts 13 can also be reduced from four to two. Furthermore, the conductive member 11 can be shortened. This allows for a reduction in the number of parts and materials used in the filter unit 100.

[0077] Furthermore, in the filter unit 100 of this embodiment, the noise removal capacitor unit 10 has a circuit board 10a and a ceramic capacitor 10b mounted on the circuit board 10a.

[0078] According to the filter unit 100 of this embodiment, the noise-removal capacitor unit 10 can be fixed to the resin housing 6. This simplifies the process of connecting the capacitor unit compared to, for example, connecting a film capacitor with a harness. Furthermore, by using a general-purpose ceramic capacitor 10b, costs can be reduced compared to using a dedicated filter capacitor.

[0079] The power conversion device 1 of this embodiment also includes a power supply terminal 5 connected to the battery B, and converts the power passing through the power supply terminal 5. The power supply terminal 5 also includes a filter unit 100 that suppresses electromagnetic noise.

[0080] According to the power conversion device 1 of this embodiment, as with the filter unit 100 of this embodiment, there is no need to provide a terminal block portion 30 separately from the resin housing 6, and the terminal block to which the bus bar 9 is fixed can be reduced.

[0081] While the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to the above-described embodiments. The shapes and combinations of the components shown in the above-described embodiments are merely examples, and various modifications can be made based on design requirements, etc., without departing from the spirit of the present invention.

[0082] For example, in the above embodiment, the filter core 7 is entirely hidden by the terminal block 30 when viewed from the radial direction. However, the present invention is not limited to this, and it is also possible to adopt a configuration in which a part of the filter core 7 protrudes from the terminal block 30 when viewed from the radial direction.

[0083] In the above embodiment, the configuration has been described in which the entire noise removal capacitor unit 10 overlaps the terminal block portion 30 when viewed from the radial direction. However, the present invention is not limited to this, and it is also possible to adopt a configuration in which the noise removal capacitor unit 10 does not overlap the terminal block portion 30 when viewed from the radial direction.

[0084] In the above embodiment, the conductive member 11 is separate from the resin housing 6. However, the present invention is not limited to this, and the conductive member 11 can be molded into the resin housing 6. In such a case, the conductive member 11 can be molded into the resin housing 6 by placing the conductive member 11 inside a mold and insert-molding the resin housing 6.

[0085] In the above embodiment, the bus bar 9 is connected to the terminal block 30. However, the terminals of the power module 3a may be connected to the terminal block 30. In the above embodiment, the bus bar 9 is connected to the terminal block 30 from the battery B side. However, the present invention is not limited to this, and it is also possible to adopt a configuration in which the bus bar 9 is connected from the power module 3a side.

[0086] The above embodiment can also be described as follows, for example:

[0087] (Supplementary Note 1) A filter unit comprising: a cylindrical filter core through which a bus bar is inserted; a resin housing that holds the filter core; and a noise-removal capacitor unit electrically connected to the bus bar, wherein the resin housing has a terminal block portion to which the bus bar is connected, and the terminal block portion is located radially outward of the filter core and is arranged so that at least a portion of the terminal block portion overlaps with the filter core when viewed from the radial outside.

[0088] (Supplementary Note 2) The filter unit according to Supplementary Note 1, characterized in that the terminal block portion has a fastening nut onto which a fastening bolt that fastens the bus bar to the terminal block portion can be threaded, and the fastening nut is arranged with a central opening facing the insertion direction of the bus bar in the filter core.

[0089] (Appendix 3) The filter unit according to appendix 1 or 2, characterized in that the noise-removal capacitor unit is located radially outside the filter core and is arranged so that at least a portion of the noise-removal capacitor unit overlaps with the filter core when viewed from the radial outside.

[0090] (Supplementary Note 4) The filter unit according to any one of Supplementary Notes 1 to 3, further comprising a conductive member that connects the noise removal capacitor unit and the bus bar, the conductive member being separate from the resin housing.

[0091] (Supplementary Note 5) The filter unit according to Supplementary Note 4, wherein the conductive member is fastened together with the bus bar to the resin housing.

[0092] (Supplementary Note 6) The filter unit according to any one of Supplementary Notes 1 to 5, wherein the noise removal capacitor unit includes: a circuit board; and a ceramic capacitor mounted on the circuit board.

[0093] (Supplementary Note 7) A power conversion device comprising a power supply terminal connected to a battery, and converting power passing through the power supply terminal, wherein the power supply terminal comprises a filter unit according to any one of Supplementary Notes 1 to 6 that suppresses electromagnetic noise.

[0094] REFERENCE SIGNS LIST 1 Power conversion device 5 Power terminal 6 Resin housing 7 Filter core 8 Core cover 9 Bus bar 9a Horizontal portion 9b Vertical portion 9b1 Bolt insertion hole 9c Branch piece 9c1 Bolt insertion hole 10 Noise removal capacitor unit 10a Circuit board 10b Ceramic capacitor 11 Conductive member 12 Frame ground connection member 13 Fastening bolt 14 Fastening bolt 20 Core holding portion 30 Terminal block portion 31 Fastening nut 32 Bus bar fastening nut (fastening nut) 33 Conductive member fastening nut (fastening nut) 34 Fastening nut 40 Fixing portion 41 Collar 100 Filter unit B Battery

Claims

1. A filter unit comprising: a cylindrical filter core through which a bus bar is inserted; a resin housing that holds the filter core; and a noise-removal capacitor unit electrically connected to the bus bar, wherein the resin housing has a terminal block portion to which the bus bar is connected, and the terminal block portion is located radially outward of the filter core and is arranged so that at least a portion of the terminal block portion overlaps with the filter core when viewed from the radial outside.

2. The filter unit according to claim 1, characterized in that the terminal block has a fastening nut onto which a fastening bolt that fastens the bus bar to the terminal block can be screwed, and the fastening nut is arranged with its central opening facing the insertion direction of the bus bar in the filter core.

3. A filter unit according to claim 1 or 2, characterized in that the noise-removal capacitor unit is located radially outside the filter core and is arranged so that at least a portion of the noise-removal capacitor unit overlaps with the filter core when viewed from the radial outside.

4. A filter unit according to claim 1 or 2, characterized in that it has a conductive member that connects the noise removal capacitor unit and the bus bar, the conductive member being separate from the resin housing.

5. The filter unit according to claim 4, wherein the conductive member is fastened together with the bus bar to the resin housing.

6. The filter unit according to claim 1 or 2, wherein the noise removal capacitor unit comprises: a circuit board; and a ceramic capacitor mounted on the circuit board.

7. A power conversion device comprising a power terminal connected to a battery and converting power passing through said power terminal, wherein said power terminal is provided with a filter unit according to claim 1 or 2 that suppresses electromagnetic noise.