Noise filter and electric conversion device

Abstract

To achieve a reduction in the size of a noise filter having a multi-wire coil of a plurality of phases.SOLUTION: A noise filter according to an embodiment of the present disclosure includes: a cooling plate; a coil; a plurality of wires; and a plurality of capacitors. The cooling plate has a thermal conductivity and is formed in a flat plate shape. The coil is a multi-wire coil having a plurality of phases and is formed in an annular shape and is fixed to a first main surface of the cooling plate. The plurality of wires are electrically connected to a lead extending from a winding of the plurality of phases. The plurality of capacitors are electrically connected to the plurality of wirings. The coil is thermally connected to the first main surface in a state of being fixed to the first main surface of the cooling plate, and an axial direction of the annular shape extends along the first main surface.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a noise filter and a power conversion device. [Background technology]

[0002] BACKGROUND ART Conventionally, power conversion devices such as an on-board charger that can operate by inputting AC voltages from a three-phase AC power supply and a single-phase AC power supply are known.

[0003] For example, Patent Document 1 discloses a technology relating to a switching power supply device that has a plurality of power conversion circuits corresponding to each phase of a multi-phase AC power supply, which is an external power supply, and is provided with a noise filter configured using a coil and a capacitor in order to suppress the ingress of noise from the external power supply and the outflow of noise to the external power supply. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2021-145448 Summary of the Invention [Problem to be solved by the invention]

[0005] In this context, there is a demand for miniaturization of power conversion devices such as chargers installed in electric vehicles, etc., due to, for example, limitations on installation space. However, when a noise filter for a power conversion device is installed with a multi-phase, multi-wire coil, space is required for routing wiring from each of the multiple windings, which limits miniaturization. For this reason, noise filters with multi-phase, multi-wire coils have room for improvement, for example, from the perspective of miniaturization.

[0006] One of the problems that the present disclosure aims to solve is to reduce the size of a noise filter having a multi-phase, multi-wire coil. [Means for solving the problem]

[0007] The noise filter according to the present disclosure comprises a cooling plate, a coil, a plurality of wires, and a plurality of capacitors. The cooling plate is thermally conductive and formed in a flat plate shape. The coil is formed in an annular shape and is a multi-phase, multi-wire coil fixed to a first main surface of the cooling plate. The plurality of wires are electrically connected to leads extending from the multi-phase windings. The plurality of capacitors are electrically connected to the plurality of wires. When fixed to the first main surface of the cooling plate, the coil is thermally connected to the first main surface, and the axial direction of the annular shape extends along the first main surface. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to achieve miniaturization of a noise filter having a multi-phase, multi-wire coil. Note that the effects described herein are not necessarily limited to those described herein, and may be any of the effects described in this specification. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view showing an example of the configuration of a noise filter mounted on a power conversion device according to an embodiment. [Figure 2] FIG. 2 is a top view showing an example of the configuration of the noise filter of FIG. [Figure 3] FIG. 3 is a cross-sectional view showing an example of the configuration of the noise filter of FIG. [Figure 4] FIG. 4 is a diagram schematically illustrating an example of the configuration of a noise filter according to a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a noise filter, a power conversion device, and a vehicle according to the present disclosure will be described with reference to the drawings.

[0011] In the description of the present disclosure, components having the same or substantially the same functions as those described above with respect to the previously-mentioned drawings may be given the same reference numerals, and descriptions thereof may be omitted as appropriate. Furthermore, even when the same or substantially the same parts are shown, the dimensions and proportions may be different depending on the drawing. Furthermore, for example, in order to ensure the visibility of the drawings, reference numerals may be given to only the main components in the description of each drawing, and reference numerals may not be given to components having the same or substantially the same functions as those described above with respect to the previously-mentioned drawings.

[0012] In the description of the present disclosure, components having the same or substantially the same functions may be distinguished by adding an alphanumeric character to the end of the reference symbol. Alternatively, when multiple components having the same or substantially the same functions are not distinguished, they may be collectively described by omitting the alphanumeric character at the end of the reference symbol.

[0013] In the description of this disclosure, expressions such as orthogonal, horizontal, vertical, parallel, identical, coincident, and the same position are not limited to strictly orthogonal, horizontal, vertical, parallel, identical, coincident, and the same position, but also include cases where they can be considered as orthogonal, horizontal, vertical, parallel, identical, coincident, and the same position.

[0014] The power conversion device according to the present disclosure may be mounted on a vehicle, for example, as an on-board charger. For example, the power conversion device may be an on-board charger that converts AC power supplied from an external single-phase or three-phase AC power source into DC power and supplies the converted DC power to a load mounted on the vehicle. The load may be, for example, a battery, an inverter, a motor, or various electrical components.

[0015] The vehicle may be any type of moving body configured to be driven or to drive its accessories (electrical components) using power from a battery, such as a passenger car, a freight vehicle, a van, a motorcycle, or an electric kick scooter. Examples of such electrical components include a navigation system, an audio system, an air conditioner, a power window, a defogger, an ECU (Electronic Control Unit), a GPS (Global Positioning System) module, and an on-board camera. The vehicle battery may be any battery capable of storing power for driving the traction motor (main motor) and electrical components mounted on the vehicle, and any battery, such as a lithium-ion battery, a nickel-metal hydride battery, or an all-solid-state battery, may be used. The power conversion device according to the present disclosure is not limited to vehicles, and may also be installed in, for example, aircraft, amusement facilities, uninterruptible power supplies, and the like.

[0016] A power conversion device according to the present disclosure is provided with a noise filter that suppresses (removes) noise from entering the power conversion device from an external AC power source and from leaking noise from the power conversion device to the AC power source. Furthermore, for example, a power conversion circuit is provided downstream of the noise filter, which converts AC power supplied from an external single-phase or three-phase AC power source via the noise filter into DC power and outputs the converted DC power. For example, this power conversion circuit is provided with a power factor correction (PFC) circuit that rectifies and smooths the AC voltage from the external AC power source after noise removal by the noise filter to generate a DC voltage. For example, a DC-DC conversion circuit is provided downstream of the PFC circuit in the power conversion circuit, which converts the DC voltage generated by the PFC circuit back into AC voltage and then rectifies and smooths the converted AC voltage to generate a DC voltage of an arbitrary set voltage.

[0017] In the power converter according to the present disclosure, the noise filter and the power conversion circuit are each disposed on the cooling surface of the housing of the power converter. As an example, the noise filter and the power conversion circuit are disposed on the cooling surface of the housing of the power converter, for example, with some or all of their components (electronic parts) integrally assembled (modularized). These modularized components are detachably fixed to the cooling surface of the housing of the power converter, for example, with fixing members (not shown) such as screws.

[0018] The noise filter and the power conversion circuit are each thermally connected to the cooling surface of the housing of the power conversion device. Here, "thermally connected" means being configured to allow heat exchange. Note that heat transfer between the noise filter and the power conversion circuit and the housing of the power conversion device is achieved by, for example, thermal conduction, but other forms may be used in addition to or instead of thermal conduction. This heat transfer may also be achieved via other components.

[0019] The housing of the power converter according to the present disclosure is formed of a metal material such as die-cast. The housing of the power converter constitutes a liquid-cooled cooling mechanism that uses a coolant such as antifreeze as the working fluid. For example, a coolant flow path extending in a direction along the cooling surface (for example, horizontally) is formed inside the housing of the power converter. In other words, the housing of the power converter has a flow path formed therein that runs within one surface (cooling surface).

[0020] The coolant flow paths formed in the housing of the power conversion device according to the present disclosure may branch in at least two directions within a single plane along the cooling surface. However, the flow paths do not branch in a direction perpendicular to the cooling surface. In other words, if the housing of the power conversion device has an intersection where flow paths in at least two directions intersect, each flow path extends from the intersection in a direction parallel to the cooling surface but does not extend in a direction perpendicular to the cooling surface. In this way, the cooling mechanism of the entire power conversion device according to the present disclosure is configured by flow paths that run only within a single plane.

[0021] (Embodiment) Fig. 1 is a perspective view showing an example of the configuration of a noise filter 1 mounted on a power conversion device according to an embodiment. Fig. 2 is a top view showing an example of the configuration of the noise filter 1 of Fig. 1. Fig. 3 is a cross-sectional view showing an example of the configuration of the noise filter 1 of Fig. 1. Fig. 3 shows a cross section of plane III-III (ZX plane) of Fig. 2 as viewed from the lower side (-Y side) of the paper.

[0022] 1 to 3, the noise filter 1 has a box-shaped housing 101 and a cooling plate 103. Note that the top surface (the XY plane on the +Z side) of the housing 101 of the noise filter 1 is not shown in FIGS. 1 to 3. The housing 101 of the noise filter 1 is made of a thermally conductive metal material such as die-cast or aluminum.

[0023] 1 to 3, the cooling plate 103 of the noise filter 1 is formed in a flat plate shape and forms the lower surface (XY plane on the -Z side) of the housing 101. The cooling plate 103 has thermal conductivity at least in the thickness direction (Z direction). Preferably, the cooling plate 103 also has thermal conductivity in the direction along the main surface (XY plane) and functions as a heat diffusion plate (heat capacity).

[0024] As shown in FIGS. 1 to 3 , the cooling plate 103 has a first main surface (XY plane) on the upper side (+Z side) of the cooling plate 103, on which the respective parts of the noise filter 1 that are to be heat dissipated (cooled) are arranged and thermally connected. Specifically, the respective parts of the noise filter 1 that are to be heat dissipated (cooled) are fixed to the first main surface so as to be able to exchange heat. The cooling plate 103 has a second main surface (XY plane) on the lower side (-Z side) of the cooling plate 103, which is the heat dissipation surface of the noise filter 1. This second main surface is arranged opposite to and thermally connected to the cooling surface of the housing of the power converter. In other words, the cooling plate 103 of the noise filter 1 according to the present disclosure transports heat from the respective parts of the noise filter 1 that are to be heat dissipated that are thermally connected to the first main surface directly or via another member to the housing of the power converter via the second main surface opposite to the first main surface.

[0025] The cooling plate 103 may be formed integrally as a part of the housing 101, or may be formed separately and fixed. This fixing may be by welding or using an adhesive, or may be detachably fixed by screws or the like.

[0026] It should be noted that the side panels (YZ planes and ZX planes) of the housing 101 extending from the outer edge of the cooling plate 103 of the noise filter 1 to the +Z side do not have to be provided. In this case, the side panels of the housing 101 may also be shared by the housing of the power conversion device in which the noise filter 1 is mounted. Similarly, the top panel (not shown) that forms the top surface of the housing 101 of the noise filter 1 may be formed integrally with the side panels as part of the housing 101, or may be formed separately and fixed to the side panels, or may also be shared by the housing of the power conversion device in which the noise filter 1 is mounted.

[0027] As described above, the noise filter 1 according to the embodiment has a structure in which the periphery is covered with the housing 101 made of a metal material. With this configuration, the housing 101 can function as a case that shields against external electromagnetic noise and also dissipates heat from heat-generating components (electronic components) such as the coil 5, as will be described later.

[0028] AC power supplied from an external single-phase or three-phase AC power supply is input to the noise filter 1 via multiple power supply lines. The noise filter 1 also outputs the AC power after noise removal via the multiple power supply lines. FIGS. 1 to 3 illustrate, as the multiple power supply lines, a voltage line L1 through which a single-phase current from the single-phase AC power supply or, for example, a U-phase (first phase) current from a three-phase AC power supply flows; two voltage lines L2 and L3 that are not electrically connected to the single-phase AC power supply but through which, for example, a V-phase (second phase) current and a W-phase (third phase) current from the three-phase AC power supply flow, respectively; and a neutral line N electrically connected to the single-phase or three-phase AC power supply. The neutral line N is also electrically connected to ground potential via a grounding line G.

[0029] 1 to 3, the noise filter 1 includes a plurality of Y capacitors 3, a plurality of X capacitors 4, a plurality of coils 5, a plurality of heat sinks 6, and at least one circuit board 7. Illustrated in FIGS. 1 to 3 are two coils 5a and 5b as examples of the plurality of coils 5.

[0030] The Y capacitors 3 are line-to-ground capacitors provided between each power supply line (i.e., multiple voltage lines L1 to L3 and a neutral line N) of the power conversion device corresponding to each of the multiple phases and the ground line G. The Y capacitors 3 attenuate common-mode noise. In the example shown in FIGS. 1 to 3, the multiple Y capacitors 3 are provided between each power supply line and the ground line G, respectively, upstream of the coil 5a, between the coils 5a and 5b, and downstream of the coil 5b. The noise filter 1 may be configured as an active noise filter. In this case, for example, the Y capacitor 3 provided between the coils 5a and 5b is electrically connected to a control circuit (not shown) such as a control IC (integrated circuit). For example, the control IC is configured to detect high-frequency noise in each power supply line using the Y capacitor 3 between the coils 5a and 5b and to pass a current of a magnitude corresponding to the detected high-frequency noise through each power supply line.

[0031] The X capacitors 4 are inter-line capacitors provided between each of the voltage lines L1 to L3 and the neutral line N (between the lines). The X capacitors 4 mainly attenuate normal mode noise. In the example of FIGS. 1 to 3, multiple X capacitors 4 are provided between each of the voltage lines L1 to L3 and the neutral line N in the upstream of the coil 5a, between the coils 5a and 5b, and in the downstream of the coil 5b.

[0032] The coil 5 is, for example, a common mode choke coil or a normal mode choke coil. As an example, the coil 5 is a three-phase, four-wire common mode choke coil composed of four windings. The coil 5 is formed by winding copper wire or the like in phase around a core made of a magnetic material. As an example, the coil 5 is a toroidal coil in which windings are arranged around a toroidal core. Note that the core of the coil 5 is not limited to a toroidal core, and any core of any shape, such as a UU core or a UI core, can be used as appropriate.

[0033] As an example, the coil 5 is formed in an annular shape such as a circular ring or a hollow rectangle (hereinafter referred to as an annular shape or simply annular). For example, the core of the coil 5 is formed or arranged in an annular shape such as a circular ring or a hollow rectangle. In other words, the core of the coil 5 may be composed of a single core formed in an annular shape, or may be formed in an annular shape by assembling (combining) multiple cores.

[0034] In the present disclosure, the axial direction of the coil 5 is defined as the direction along the central axis or the direction in which the inner periphery of the annular shape extends. Here, the inner periphery of the annular shape is defined as the hollow portion or its vicinity. In other words, the axial direction of the coil 5 is defined as the direction in which the columnar shape defined by the hollow portion of the annular shape extends. For example, in the state shown in FIGS. 1 to 3, the axial direction of the coil 5 is defined as the direction along the X-axis extending along the cooling plate 103, i.e., the direction along the flow of the arrangement of the mounted components (electronic components) of the noise filter 1. In addition, in the present disclosure, the radial direction of the coil 5 is defined as the direction perpendicular to the axial direction, i.e., the direction from the inner periphery of the annular shape to the outer periphery.

[0035] A pair of leads extend from both ends of each of the multiple windings of the coil 5 and are electrically connected to either one of the voltage lines L1 to L3 or the neutral line N. In the present disclosure, for example, with respect to each of the multiple power supply lines (voltage lines L1 to L3 and neutral line N), the "start of winding" of a winding refers to the lead on the input side of each phase. Similarly, for example, the "end of winding" of a winding refers to the lead on the output side of each phase.

[0036] Coil 5 may be a three-phase, three-wire coil made up of three windings electrically connected to voltage lines L1 to L3, respectively. Coil 5 has a filtering function for three phases with one coil, so costs can be reduced compared to using three single-phase coils.

[0037] The coil 5 is thermally connected to the cooling plate 103 of the noise filter 1. The coil 5 is held by a holding member (not shown) such as a resin mold, and its position and posture are determined.

[0038] 1 to 3, the winding start and end of all of the windings of the multiple power supply lines (voltage lines L1 to L3 and neutral line N) are at different positions in the circumferential direction around the axial direction of the ring shape of coil 5. In other words, the positions of the leads of coil 5 in the circumferential direction differ between the multiple phases and also between the input side and the output side.

[0039] For example, as shown in FIGS. 1 to 3, the start and end of the winding for each of the multiple power supply lines (voltage lines L1 to L3 and neutral line N) are located at the same radial position of the ring-shaped coil 5 and are aligned concentrically. Specifically, the start and end of the winding for each of the multiple power supply lines are aligned on either the outer or inner side of the ring-shaped core. In other words, the position (position on the YZ plane) in the radial direction perpendicular to the axial direction (X direction) of the ring-shaped coil 5 is aligned on either the inner or outer side of the ring-shaped coil for each of the multiple phases between a pair of input and output leads. Note that the radial position of the coil 5 for any of the multiple phases, i.e., whether it is on the inner or outer side, may be different between the input and output leads. In other words, the positions of the input and output leads of the coil 5 may differ between the inner and outer periphery of the ring shape for some phases (at least one phase), and may be aligned on either the inner or outer periphery for the other phases. Whether or not to vary the radial positions of the input and output leads for any phase, or which phases to vary the radial positions for, can be determined appropriately based on the arrangement of mounted components including the coil 5, the routing of wiring, and the like. In other words, varying the radial positions of the input and output leads for any phase can further improve the flexibility of routing mounted components and wiring.

[0040] 1 to 3, for each of the multiple power supply lines (voltage lines L1 to L3 and neutral line N), the winding start and end are located on opposite sides in the axial direction of the annular core (coil 5). Specifically, the multiple input-side power supply lines electrically connected to one of the winding start and end are provided on the opposite side in the axial direction of the coil 5 from the multiple output-side power supply lines electrically connected to the other winding. In other words, for each of the multiple phases, the input-side lead and the output-side lead extending from the winding of the coil 5 extend on opposite sides in the axial direction of the annular shape of the coil 5.

[0041] 1 to 3, the coil 5 is arranged on the first main surface of the cooling plate 103 in a state where it stands perpendicular to the main surface (XY plane) of the cooling plate 103. In other words, the coil 5 is arranged on the first main surface of the cooling plate 103 in an orientation that reduces the projected area of ​​the coil 5 on the main surface of the cooling plate 103. Specifically, as shown in FIGS. 1 to 3, the coil 5 is arranged on the cooling plate 103 of the noise filter 1 so that its axial direction coincides with the direction (X direction) along the flow of arrangement of mounted components (electronic components) in the noise filter 1. In other words, with respect to the coil 5 arranged on the cooling plate 103 of the noise filter 1, the start and end of each winding are provided on opposite sides to each other in the direction (X direction) along the flow of arrangement of the electronic components in the noise filter 1.

[0042] 2 and 3, in the noise filter 1 according to the present disclosure, the positions of the winding start points of the multiple windings of multiple phases in the direction along the flow of the arrangement of electronic components (X direction) are aligned for the coils 5 arranged on the cooling plate 103 of the noise filter 1. In other words, the positions of the ring-shaped input leads of the coils 5 in the axial direction (X direction) are aligned across all multiple phases.

[0043] 2 and 3, in the noise filter 1 according to the present disclosure, the positions of the winding ends of the multiple windings of the multiple phases in the direction along the flow of the arrangement of electronic components are aligned for the coils 5 arranged on the cooling plate 103 of the noise filter 1. In other words, the positions of the ring-shaped output leads of the coils 5 in the axial direction (X direction) are aligned across all multiple phases.

[0044] As shown in FIGS. 1 to 3, multiple power supply lines (voltage lines L1 to L3 and neutral line N) electrically connected to coil 5 extend from the start and end of each winding in a direction following the flow of the arrangement of electronic components in noise filter 1.

[0045] In this way, the coil 5 of the noise filter 1 according to this embodiment is configured so that both ends of the winding are pulled out on opposite sides in the axial direction. The radial position of the winding start relative to the core of this coil 5 is the same as that of a coil configured so that both ends of the winding are pulled out on the same side in the axial direction, and it is only necessary to change the winding end position, i.e., the number of turns by halfway around the core, so that ease of manufacturing can be maintained.

[0046] The heat sink 6 is a member formed in a flat plate shape. The heat sink 6 is formed using a thermally conductive metal material such as die-cast or aluminum. The type of metal material or the thickness (length in the X direction) of the heat sink 6 may be selected appropriately depending on, for example, the amount of heat dissipation from the coil 5 and the distance from the coil 5. The heat sink 6 is not an essential component, and may not be provided in the noise filter 1. For example, if the housing 101 is filled with a heat dissipation buffer material such as a potting material or the packaging density in the housing 101 is low, and heat can be dissipated appropriately from the coil 5, the noise filter 1 may not need to be provided with the heat sink 6.

[0047] 1 to 3, a plurality of heat sinks 6 are provided on both sides of each of the coils 5a and 5b in the direction (X direction) along the flow of the arrangement of the electronic components. The heat sinks 6 are also placed on and thermally connected to the cooling plate 103 of the noise filter 1. The heat sinks 6 transport heat from the coils 5 to the cooling plate 103 and dissipate the heat. The main surface (YZ plane) of the heat sink 6 extends in a direction away from the cooling plate 103. This direction away from the cooling plate 103 is, for example, a direction perpendicular to the cooling plate 103 (Z direction).

[0048] The heat sink 6 may be disposed on only one side of each of the coils 5a, 5b in the direction (X direction) along the flow of the arrangement of the electronic components. In other words, a plane (YZ plane) perpendicular to the axial direction (X direction) of the ring shape of the coil 5 faces each main surface of at least one heat sink 6. For example, the coil 5 is disposed between the main surfaces of a pair of heat sinks 6 in the axial direction (X direction) of the ring shape.

[0049] The main surface of the heat sink 6 may be inclined with respect to the YZ plane. That is, the heat sink 6 is orthogonal to, for example, the cooling plate 103 of the noise filter 1, but can be inclined appropriately with respect to the cooling plate 103 depending on, for example, restrictions in the height direction (Z direction) and the layout of each component.

[0050] The cooling plate 103 and the plurality of heat sinks 6 of the noise filter 1 may be integrally formed, or may be formed separately and fixed together. This fixing may be by welding or using an adhesive, or may be detachably fixed by screwing or the like.

[0051] In this way, by arranging the coil 5 perpendicular to the main surface of the cooling plate 103, it is possible to align the electrical flow in the noise filter 1 with the layout flow (terminal layout) of the electronic components. Therefore, with the above-mentioned configuration, it is possible to reduce unnecessary routing of power lines (wiring) between the electronic components and realize a miniaturized noise filter 1.

[0052] Furthermore, by configuring the input side and output side of all of the multiple phases to be on opposite sides in the direction along the flow of the electronic component layout, even when a multi-wire coil 5 with three or more windings is used, there is no intersection between the input side wiring (power supply line) and the output side wiring, and there is no intersection between the wiring between phases, reducing the risk of deterioration of filter performance due to capacitive coupling at the intersections.

[0053] Furthermore, in the noise filter 1, the X capacitors 4 and Y capacitors 3 before and after the coil 5 can also be arranged in an orderly manner along the electrical flow, thereby reducing the dead space that accompanies wiring routing.

[0054] 1 to 3, the heat sink 6 is shorter than the width (length in the Y direction) of the housing 101 of the noise filter 1. Here, the width of the housing 101 of the noise filter 1 refers to the length in a direction along the first main surface of the cooling plate 103 that is perpendicular to the axial direction (X direction) of the ring shape of the coil 5. In the width direction of the housing 101, a gap 105 is formed between at least one heat sink 6 and a side plate of the housing 101 of the noise filter 1. Note that the gap 105 does not necessarily have to be provided.

[0055] As an example, the voltage wires L1 to L3 of the multiple power supply lines (multiple wirings) of multiple phases are routed above (on the +Z side of) the heat sink 6. For example, in a power conversion device configured to be operable by input of both single-phase and three-phase AC power supplies using a three-phase, four-wire coil 5, when three-phase AC power is input, the N-phase current is canceled out due to the phase difference between the phases. On the other hand, when single-phase AC power is input, a large current flows through the N-phase, resulting in greater loss than the other L-phases. For this reason, the neutral wire N of the N-phase among the four wirings connected to the three-phase, four-wire coil 5 generates more heat than the other L-phase voltage wires L1 to L3. For this reason, in the case of a three-phase, four-wire system, the neutral wire N passes through a gap 105 between the housing 101 of the noise filter 1 and the heat sink 6 and is routed near the cooling plate 103. Note that in addition to or instead of the N-phase, power supply lines of other phases may be routed through the gap 105. That is, a power supply line (wiring) corresponding to at least one phase of the multiple power supply lines (voltage lines L1 to L3, neutral line N) of multiple phases is routed inside the housing 101 on the side of the cooling plate 103 and passes through the gap 105.

[0056] The circuit board 7 has a wiring pattern formed thereon, including wiring electrically connected to, for example, multiple power supply lines of multiple phases, multiple Y capacitors 3 provided between the coils 5a and 5b, and multiple X capacitors 4, and electrically connecting the lines or the lines to ground. For example, in a noise filter 1 configured as an active noise filter, the circuit board 7 may be mounted with a control IC and its peripheral circuitry configured to detect high-frequency noise using the Y capacitor 3 provided between the coils 5a and 5b and pass a noise cancellation current corresponding to the detected high-frequency noise through each power supply line. Note that the circuit board 7 may not be provided in some cases, such as when all connections between the power supply lines and the components are directly joined by welding or the like.

[0057] Furthermore, in the noise filter 1 according to this embodiment, a heat-dissipating buffer material, such as a filler or potting material, having at least heat dissipation (thermal conductivity) and electrical insulation properties may be filled between at least one heat sink 6 and the coil 5. That is, in the noise filter 1, a heat-dissipating buffer material may be filled between at least a pair of heat sinks 6 facing each other across the coil 5. That is, the heat-dissipating buffer material may be used as a heat dissipation path from the coil 5. Note that if the components arranged inside the housing 101 of the noise filter 1, such as the coil 5, are insulated or if a sufficient insulation distance is ensured, the heat-dissipating buffer material does not need to have electrical insulation properties. Alternatively, the heat-dissipating buffer material may fill the entire interior of the housing 101 of the noise filter 1.

[0058] In this way, by filling the coil 5 with a heat dissipation buffer material, it is possible to ensure an insulating distance between the coil 5 and its surroundings while minimizing the physical length. Furthermore, the components of the noise filter 1, such as the coil 5, can be held in place by the filled heat dissipation buffer material, so that vibration countermeasures for the noise filter 1 can be achieved while reducing structures for vibration countermeasures, such as support members and fixing members, such as molds.

[0059] 1 to 3, electrical connections between components in noise filter 1, such as the connections between coils 5a and 5b and Y capacitor 3 and X capacitor 4, are achieved by directly joining the leads of mounted components (electronic components) by welding or other methods, without using a circuit board. This configuration can prevent the increase in structure that would otherwise accompany an increase in connection points, such as by arranging fixing members such as screws or bus bars to relay electrical connections. This allows for the reduction of the number of circuit boards and the miniaturization of the mounted circuit boards.

[0060] The power conversion device according to the present disclosure includes circuit components upstream or downstream of the noise filter 1, such as an AC connector, fuse, varistor, and phase switching relay. Electrical connections between these circuit components and the noise filter 1, or between circuit components themselves, may also be achieved by directly joining the leads of the mounted components by welding or the like, without using a circuit board. This configuration allows for the overall miniaturization of the power conversion device incorporating the noise filter 1.

[0061] Furthermore, the noise filter 1 according to the embodiment may be disposed in the housing 101 together with circuitry upstream or downstream of the noise filter 1, such as an AC connector, fuse, varistor, or phase-switching relay, to form an integrated noise filter module. For example, the circuit board 7 may be mounted with a control circuit for a phase-switching relay (not shown) or a relay for an inrush current prevention circuit (not shown). For example, the control circuit for the phase-switching relay controls the operation of the phase-switching relay to switch the phase of AC power supplied to each of the voltage lines L1 to L3 between a phase corresponding to each voltage line and a single phase common to the voltage lines L1 to L3. For example, the control circuit for the relay for the inrush current prevention circuit controls the operation of the relay for the inrush current prevention circuit, which is provided in parallel with an inrush current prevention element, such as a thermal fuse resistor, cement resistor, or thermistor, in the inrush current prevention circuit, to prevent inrush current from flowing to a power factor correction circuit (not shown) downstream of the noise filter 1. This configuration reduces the manufacturing costs of the power conversion device.

[0062] Furthermore, the power conversion device according to the present disclosure may be expandable by mounting multiple noise filters 1 in series or in parallel. That is, the power conversion device according to the present disclosure may be scalable by modularizing multiple components by arranging them in the housing 101. A configuration in which multiple noise filters 1 are mounted in series or in parallel can further suppress noise from entering the power conversion device or leaking to the outside.

[0063] Some of the electrical connections between the components in noise filter 1 may be made via a circuit board such as circuit board 7, or may be realized by disposing a junction holder above (on the +Z side of) housing 101 that has a bus bar for relaying the electrical connections and a resin mold that holds the bus bar or the mounted components.

[0064] (Comparative Example) Fig. 4 is a diagram schematically illustrating an example of the configuration of a noise filter 9 according to a comparative example. Fig. 4 schematically illustrates the configuration of the noise filter 9 according to the comparative example as viewed from the top side (+Z side).

[0065] In order to cool a coil 8 such as a common mode choke coil, as in the noise filter 9 according to the comparative example, the annular coil 8 is often placed horizontally with its heat dissipation surface (the surface on the -Z side) parallel to the cooling surface of the housing, i.e., with its axial direction perpendicular to the cooling surface of the housing. When the coil 8 is placed horizontally, a circuit board (not shown) that electrically connects the coil (electronic component) to the mounted components (electronic components) upstream and downstream of the coil 8 may be placed parallel to the heat dissipation surface of the coil 8, for example, following the layout of the electronic components.

[0066] For example, even if a single-phase coil is placed horizontally, the wiring from the coil and the layout of the surrounding electronic components are simple.

[0067] In this situation, in the case of a multi-phase, multi-wire toroidal coil 8, for example, for ease of manufacturing, the winding start of all of the multiple windings of the multiple phases is located on the outer periphery of the core and the winding end is located on the inner periphery, and the winding start and winding end are drawn out to the same side (e.g., the +Z side) in the axial direction (Z direction). For this reason, when a multi-wire coil 8 with three or more windings, such as a three-phase, four-wire toroidal common mode choke coil, is placed horizontally as shown in Figure 4, the winding structure causes the multiple power supply lines (wiring) connected to the multiple windings to cross each other, which is cumbersome, and requires space for routing the power supply lines. In addition, the placement of X capacitors 4, for example, located before and after the coil 8, can also be cumbersome, requiring additional space for routing the wiring.

[0068] Generally, there is a demand for miniaturization of power conversion devices such as chargers mounted on electric vehicles, etc., due to, for example, limitations on mounting space. For this reason, there is room for improvement in noise filters having multi-phase multi-wire coils, for example, from the perspective of miniaturization.

[0069] Furthermore, for example, if a square coil 8 is used, the complexity of wiring can be reduced, but there is a problem that the cost increases.

[0070] 4, in the direction along the flow of the layout of the electronic components (X direction), winding start positions P11, P12, P13, and P14 are different from one another. Therefore, space is required on both the input and output sides of coil 8 for routing the wiring.

[0071] Furthermore, for example, when a multi-wire common mode coil with three or more windings is placed horizontally as shown in Fig. 4, there may be intersections such as an intersection Q1 where the input side voltage line L2 and the output side voltage line L1 intersect, or an intersection Q2 where the input side and output side neutral lines N intersect. At the intersections of the input side wiring (power supply line) and the output side wiring, or at the intersections of the wiring between phases, there is a risk of filter performance deteriorating due to capacitive coupling.

[0072] In contrast to the noise filter 9 according to the comparative example, the noise filter 1 according to the present disclosure has a multi-phase, multi-wire coil 5 that is vertically placed on a horizontal cooling surface (the first main surface of the cooling plate 103), and the input and output leads of the coil 5 are drawn out on opposite sides in the axial direction (X direction) of the coil 5.

[0073] According to the configuration of the present disclosure, in which the coil 5 is arranged vertically to the main surface of the cooling plate 103, it is possible to match the electrical flow in the noise filter 1 with the layout flow (terminal layout) of the electronic components. Therefore, according to the configuration of the present disclosure, it is possible to reduce unnecessary routing of power lines (wiring) between the electronic components and to achieve a miniaturized noise filter 1.

[0074] Furthermore, according to the configuration of the present disclosure in which the input side and output side are arranged on opposite sides in the direction along the flow of the electronic component arrangement for all of the multiple phases, even when a multi-wire common mode coil with three or more windings is used, there is no intersection between the input side wiring (power supply line) and the output side wiring, and there is no intersection between the wiring between phases, thereby reducing the risk of deterioration of filter performance due to capacitive coupling at the intersection.

[0075] According to at least one of the embodiments described above, it is possible to reduce the size of a noise filter having a multi-phase multi-wire coil.

[0076] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention described in the claims and their equivalents.

[0077] (Addendum) The above description of the embodiments discloses the following techniques. (1) a cooling plate having thermal conductivity and formed in a flat plate shape; a multi-phase multi-wire coil formed in an annular shape and fixed to the first main surface of the cooling plate; a plurality of wires electrically connected to leads extending from the plurality of phase windings; a plurality of capacitors electrically connected to the plurality of wirings, The coil is thermally connected to the first main surface in a state where the coil is fixed to the first main surface of the cooling plate, and an axial direction of the annular shape extends along the first main surface. Noise filter. (2) In each of the plurality of phases, an input lead and an output lead extending from a winding of the coil extend in opposite directions in the axial direction of the annular shape. The noise filter according to (1) above. (3) the positions of the input leads in the axial direction of the annular shape are aligned across all of the multiple phases; The positions of the output leads in the axial direction are aligned across all of the multiple phases. The noise filter according to (1) or (2) above. (4) a position of the input lead in a radial direction perpendicular to the axial direction of the annular shape and a position of the output lead in the radial direction are aligned on either an inner circumferential side or an outer circumferential side of the annular shape for each of the multiple phases; The noise filter according to any one of (1) to (3) above. (5) The position of the input lead in a radial direction perpendicular to the axial direction of the annular shape and the position of the output lead in the radial direction are Some of the phases are different between an inner circumferential side and an outer circumferential side of the annular shape, Other phases among the plurality of phases are aligned on either the inner circumferential side or the outer circumferential side for each phase. The noise filter according to any one of (1) to (3) above. (6) a position of the lead in a circumferential direction around the axial direction of the annular shape differs among the multiple phases and also differs between the input side and the output side; The noise filter according to any one of (1) to (5) above. (7) Further, at least one heat sink having thermal conductivity and formed in a flat plate shape is provided, a surface of the coil that is perpendicular to the axial direction of the annular shape faces each main surface of the at least one heat sink; The noise filter according to any one of (1) to (6) above. (8) Further provided is a side plate extending from an outer edge of the cooling plate toward the first main surface, the cooling plate and the side plate form a housing of the noise filter; a gap is formed between the at least one heat sink and the side plate in a direction along the first main surface perpendicular to the axial direction of the ring shape of the coil; a wiring corresponding to at least one of the plurality of phases among the plurality of wirings is routed on the cooling plate side inside the housing of the noise filter and passes through the gap; The noise filter according to (7) above. (9) A heat dissipation buffer material having at least thermal conductivity is filled between the coil and the at least one heat dissipation plate. The noise filter according to (7) or (8) above. (10) The coil is a toroidal coil. The noise filter according to any one of (1) to (9) above. (11) The noise filter according to any one of (1) to (10) above; a housing having a flow path for a cooling liquid formed therein, the flow path running within one surface; the noise filter is detachably fixed to the housing, When the noise filter is fixed to the housing, a second main surface of the noise filter, which is opposite to the first main surface of the cooling plate, is thermally connected to the housing. Power conversion device. (12) The noise filter according to any one of (1) to (10) above; a power conversion circuit disposed downstream of the noise filter, converting AC power supplied from an external single-phase or three-phase AC power supply via the noise filter into DC power, and outputting the converted DC power. Power conversion device. (13) The power conversion device according to (11) or (12), a battery that is charged using the DC power converted by the power conversion device. vehicle. [Explanation of symbols]

[0078] 1. Noise filter 101 Case 103 Cooling plate 105 Gap 3 Y capacitors 4 x Capacitors 5, 5a, 5b coils 6 Heat sink 7 Circuit Board 8 coils 9 Noise Filter L1, L2, L3 voltage lines N Neutral wire G ground wire

Claims

1. a cooling plate having thermal conductivity and formed in a flat plate shape; a multi-phase multi-wire coil formed in an annular shape and fixed to the first main surface of the cooling plate; a plurality of wires electrically connected to leads extending from the plurality of phase windings; a plurality of capacitors electrically connected to the plurality of wirings, The coil is thermally connected to the first main surface in a state where the coil is fixed to the first main surface of the cooling plate, and an axial direction of the annular shape extends along the first main surface. Noise filter.

2. In each of the plurality of phases, an input lead and an output lead extending from a winding of the coil extend in opposite directions in the axial direction of the annular shape. The noise filter according to claim 1 .

3. the positions of the input leads in the axial direction of the annular shape are aligned across all of the multiple phases; The positions of the output leads in the axial direction are aligned across all of the multiple phases. The noise filter according to claim 2 .

4. a position of the input lead in a radial direction perpendicular to the axial direction of the annular shape and a position of the output lead in the radial direction are aligned on either an inner circumferential side or an outer circumferential side of the annular shape for each of the multiple phases; The noise filter according to claim 2 .

5. The position of the input lead in a radial direction perpendicular to the axial direction of the annular shape and the position of the output lead in the radial direction are Some of the phases are different between an inner circumferential side and an outer circumferential side of the annular shape, Other phases among the plurality of phases are aligned on either the inner circumferential side or the outer circumferential side for each phase. The noise filter according to claim 2 .

6. a position of the lead in a circumferential direction around the axial direction of the annular shape differs among the multiple phases and also differs between the input side and the output side; The noise filter according to claim 2 .

7. The device further includes at least one heat sink having thermal conductivity and formed in a flat plate shape, a surface of the coil that is perpendicular to the axial direction of the annular shape faces each main surface of the at least one heat sink; The noise filter according to claim 1 .

8. a side plate extending from an outer edge of the cooling plate toward the first main surface, the cooling plate and the side plate form a housing of the noise filter; a gap is formed between the at least one heat sink and the side plate in a direction along the first main surface perpendicular to the axial direction of the ring shape of the coil, a wiring corresponding to at least one of the plurality of phases among the plurality of wirings is routed inside the housing of the noise filter on the side of the cooling plate and passes through the gap; The noise filter according to claim 7.

9. A heat dissipation buffer material having at least thermal conductivity is filled between the coil and the at least one heat dissipation plate. The noise filter according to claim 7.

10. The coil is a toroidal coil. The noise filter according to claim 1 .

11. The noise filter according to any one of claims 1 to 10; a housing having a flow path for a cooling liquid formed therein, the flow path running within one surface; the noise filter is detachably fixed to the housing, When the noise filter is fixed to the housing, a second main surface of the noise filter, which is opposite to the first main surface of the cooling plate, is thermally connected to the housing. Power conversion device.

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