JP2018121406A - Power converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power converter capable of certainly preventing heat receiving of a capacitor with a relatively simple configuration.SOLUTION: A power converter includes: an inverter; connection conductors 5an, 5bn for feeding power to the inverter; and a filter circuit that includes a capacitor circuit and being implemented in the connection conductor. The power converter also includes: a conductor unit 6 to which a first capacitor is electrically connected and becoming a wiring unit of the capacitor circuit; and a cooler 9 on which the capacitor is mounted. The connection conductors, the conductor unit, and the cooler are arranged so as to overlap with each other. The connection conductors are electrically connected with the conductor unit. The conductor unit comes into thermally contact with an extension unit 9an of the cooler.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a power conversion device suitable for cooling a capacitor.

  A voltage source inverter (hereinafter referred to as an “inverter”) is a power conversion device that converts a DC voltage into an AC voltage, and is widely used for variable-speed drive applications of AC motors. Inverters are also one of the core components of hybrid electric vehicles and electric vehicles that expand the market scale against the backdrop of growing environmental awareness.

  In the inverter, a three-phase current flowing in the motor is detected, and a predetermined control calculation is performed by a microprocessor or the like so that the detected value follows the current command, and in response to the result, switching that configures the inverter The element is on / off controlled. The motor generates torque according to the energization current.

  At that time, high-frequency noise accompanying on / off of the switching element is superimposed on the AC output and DC input of the inverter. Since this high frequency noise becomes a radio wave and adversely affects a radio or the like, a filter circuit for reducing the noise is used in the inverter.

  The filter circuit is provided in the power supply path from the battery to the inverter, but heat is generated in the power supply conductor due to power loss. For this reason, a filter component such as a capacitor receives heat from the conductor, and the temperature of the filter component may exceed an allowable value.

  On the other hand, for example, a technique described in Patent Document 1 is known. In the present technology, a heat transfer body made of a conductor is fastened to a connection conductor that electrically connects the capacitor and the switching element. This heat transfer body is in contact with a cooler on which a capacitor and a switching element are placed via an electrical insulating material. Thereby, the heat of the connection conductor is radiated to the cooler via the heat transfer body, so that the heat reception of the capacitor is reduced.

Japanese Patent No. 5714077

  In the above prior art, the number of components increases because the heat transfer body is fastened to the connection conductor. In addition, it is necessary to reduce the thermal resistance at the two locations of the connection surface between the connection conductor and the heat transfer body and the connection surface between the heat transfer body and the cooler. difficult.

  Therefore, the present invention provides a power conversion device that can reliably prevent heat reception of a capacitor with a relatively simple configuration.

  In order to solve the above problems, a power conversion device according to the present invention includes an inverter, a connection conductor that supplies power to the inverter, and a filter circuit that includes a capacitor circuit and is mounted on the connection conductor. The first capacitor is electrically connected, and includes a conductor portion serving as a wiring portion of the capacitor circuit, and a cooler on which the capacitor is placed. The connection conductor, the conductor portion, and the cooler overlap each other. The connection conductor is electrically connected to the conductor portion, and the conductor portion is in thermal contact with the extending portion of the cooler.

  According to the present invention, the connecting conductor, the conductor portion 6 and the cooler 9 are arranged so as to overlap each other, and the conductor portion is in thermal contact with the extending portion of the cooler. Can be prevented from receiving heat.

  Problems, configurations, and effects other than those described above will become apparent from the following description of embodiments.

It is a circuit diagram of the motor drive system which is one embodiment of the present invention. The circuit structure of a condenser cooling device is shown. A mounting bird's-eye view of the condenser cooling device is shown. The front view of a capacitor | condenser cooling device and the side view seen from the X capacitor | condenser side are shown. The modification of the connection structure of the connection conductor in the 1st conductor part and the 2nd conductor part is shown. The modification of the connection structure of the connection conductor in the 1st conductor part and the 2nd conductor part is shown. The modification of the connection structure of the connection conductor in the 1st conductor part and the 2nd conductor part is shown. The connection structure by a spring electrode in this embodiment is shown.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same reference numerals indicate the same constituent elements or constituent elements having similar functions.

  FIG. 1 is a circuit diagram of a motor drive system according to an embodiment of the present invention.

  The motor drive system includes a battery 1 shown in FIG. 1, a power conversion device including an EMC filter 2 (EMC: Electric Magnetic Compatibility) and an inverter 3, and an AC motor 4. The power converter includes a current detector, a voltage detector, a rotation angle detector, and a control circuit that are not shown.

  In the inverter 3, the collector terminals of the upper arm transistors Tu +, Tv +, and Tw + are connected to the connection conductor to the positive electrode of the battery 1, and the emitter terminals of the lower arm transistors Tu−, Tv−, and Tw− are connected to the battery 1. Connected to the connecting conductor to the negative electrode. The emitter terminals of the transistors Tu +, Tv +, and Tw + are connected to the collector terminals of the paired transistors Tu−, Tv−, and Tw−, respectively, and the connection points are connected to the phases of the AC motor 4 ( U phase, V phase, W phase).

  In this embodiment, an insulated gate bipolar transistor (IGBT) is applied as a transistor that is a semiconductor switching element, but other semiconductor switching elements such as MOSFETs may be applied. Moreover, as the AC motor 4, for example, a permanent magnet synchronous motor is applied.

  The collector terminals of the transistors Tu +, Tv +, Tw +, Tu−, Tv−, and Tw− are connected to the cathode terminals of the diodes Du +, Dv +, Dw +, Du−, Dv−, and Dw−, respectively. The anode terminals of the diodes Du +, Dv +, Dw +, Du−, Dv−, and Dw− are connected to the emitter terminals of Tv +, Tw +, Tu−, Tv−, and Tw−, respectively. That is, diodes Du +, Dv +, Dw +, Du−, Dv−, and Dw− are connected in reverse parallel to the transistors Tu +, Tv +, Tw +, Tu−, Tv−, and Tw−, respectively. Operate.

  Further, in the inverter 3, one end of a smoothing capacitor Cs that absorbs a ripple current associated with switching of the transistors Tu +, Tv +, Tw +, Tu−, Tv−, and Tw− is connected to a connection conductor to the positive electrode of the battery 1 so as to be smooth. The other end of the capacitor Cs is connected to a connection conductor to the negative electrode of the battery 1.

  The EMC filter 2 includes an X capacitor (Cx1, Cx2) for reducing normal mode noise including a frequency component of medium and short waves (0.1 to 30 MHz) that is not substantially absorbed by the smoothing capacitor Cs, and a winding of the AC motor 4 Consists of a Y capacitor (Cy1-1, Cy1-2, Cy2-1, Cy2-2) that absorbs common mode noise flowing from the capacitor to the case ground via a parasitic capacitance, and a common mode choke CMC for reducing common mode noise The battery 1 is mounted on a connection conductor between the battery 1 and the inverter 3 that supplies the DC power of the battery 1 to the inverter 3. Such an EMC filter 2 can reduce the influence of medium and short wave noise on peripheral electronic devices such as a radio.

  As shown in FIG. 1, capacitors Cy1-1 and Cy1-2 constituting the Y capacitor on the battery side are connected in series, and the series connection point 6c1 is connected to the case ground. One terminal 8c1 of the Y capacitor, that is, the terminal paired with the series connection point in the capacitor Cy1-1 is connected to the connection conductor 5a1 to the positive electrode of the battery 1. The other end 8d1 of the Y capacitor, that is, the terminal paired with the series connection point in the capacitor Cy1-2 is connected to the connection conductor 5b1 to the negative electrode of the battery 1.

  The capacitors Cy2-1 and Cy2-2 constituting the Y capacitor on the inverter side are connected in series, and the series connection point 6c2 is connected to the case ground. One terminal 8c2 of the Y capacitor, that is, the terminal paired with the series connection point in the capacitor Cy2-1 is connected to the connection conductor 5a2 to the positive electrode of the battery 1. Further, the other end 8d2 of the Y capacitor, that is, the terminal paired with the series connection point in the capacitor Cy2-2 is connected to the connection conductor 5b2 to the negative electrode of the battery 1.

  Terminals 8a1 and 8b1 of the capacitor Cx1 constituting the X capacitor on the battery side are connected to the connection conductors 5a1 and 5b1, respectively. The terminals 8a2 and 8b2 of the capacitor Cx2 constituting the X capacitor on the inverter side are connected to the connection conductors 5a2 and 5b2, respectively.

  The common mode choke CMC is connected between the battery side capacitor group (Cx1, Cy1-1, Cy1-2) and the inverter side capacitor group (Cx2, Cy2-1, Cy2-2). In the present embodiment, the common mode choke CMC has a configuration in which a connection conductor is passed through a doughnut-shaped choke core (magnetic material). This configuration is preferable for the inverter 3 that handles a large current (for example, 100 A or more). In this case, the connection conductors 5a1 and 5a2 in FIG. 1 are formed of an integral wiring conductor, such as a single cable or bus bar. Similarly, the connection conductors 5b1 and 5b2 are formed of an integral wiring conductor.

  When the motor drive system is mounted, the common mode choke CMC is connected between the Y capacitor on the battery side and the Y capacitor on the inverter side, between the X capacitor on the battery side and the X capacitor on the inverter side, and on the Y side on the battery side. It may be positioned between the capacitor and the X capacitor on the inverter side, or between the X capacitor on the battery side and the Y capacitor on the inverter side.

  Here, since a current supplied from the battery to the inverter flows through the connection conductor between the inverter and the battery, power loss occurs due to the resistance of the conductor. For this reason, the temperature of the connection conductor rises, heat is transmitted to the capacitor connected to the connection conductor, and the temperature of the capacitor is increased. Therefore, in this embodiment, a capacitor cooling device including a capacitor group (X capacitor and Y capacitor) is configured as described below.

  FIG. 2 shows a circuit configuration of the condenser cooling device. FIG. 3 shows a mounting bird's-eye view of the condenser cooling device. Further, FIG. 4 shows a front view of the condenser cooling device and a side view seen from the X condenser (Cxn) side. In addition, “n” in the reference numerals appended to each part indicates that the battery side if n = 1, and the inverter side if n = 2 (see FIG. 1).

  As shown in FIG. 2, the condenser cooling device includes one condenser group (Cxn, Cyn-1, Cyn-2: n = 1, 2). This capacitor group constitutes one capacitor circuit in the EMC filter 2 (FIG. 1). Therefore, the motor drive system of this embodiment includes a condenser cooling device on each of the battery side and the inverter side.

  As shown in FIGS. 3 and 4, in the condenser cooling device, from below, the cooler 9, the condenser group (Cxn, Cyn−1, Cyn−2), the second conductor part 6, and the first conductor part. 5 are arranged to be stacked in this order, that is, to overlap each other.

  A capacitor group is placed on the plane of the cooler 9. Each capacitor has a pair of terminals on one surface, and is placed on the flat portion 9cn of the cooler 9 with the surface having the terminals facing up. The cooler 9 includes an extending portion 9an extending perpendicularly to the surface on which the capacitor group is placed in the flat surface portion 9cn. On the plane portion 9cn, the X capacitor (Cxn) and the Y capacitor (Cyn-1, Cyn-2) are arranged so as to sandwich the extending portion 9an. That is, the extending portion 9an is located between the X capacitor and the Y capacitor, and the extending portion 9an, the X capacitor, and the Y capacitor are adjacent to each other on the plane portion 9cn. A through hole for allowing the coolant to flow is provided in the flat portion 9cn of the cooler. In addition, on the surface on which the capacitor group is placed in the plane portion 9cn, it faces the connection terminal 6hn in the second conductor portion 6 in order to connect the series connection point of the capacitors Cyn-1 and Cyn-2 to the case ground. A cylindrical boss 9bn is provided at a position to be used.

  The extending portion 9an, the cylindrical boss 9bn, and the planar portion 9cn of the cooler 9 are configured by members (for example, metal bodies) having good thermal conductivity and good electrical conductivity. Further, the extending portion 9an, the cylindrical boss 9bn, and the flat surface portion 9cn may be configured integrally or may be configured by connecting separate members.

  As shown in FIG. 3, in the second conductor portion 6, conductor patterns 6 an and 6 bn are formed on the surface of the insulating resin plate 7 in order to connect the terminals of each capacitor to form the capacitor circuit shown in FIG. 2. , 6cn are provided. That is, the second conductor portion 6 becomes a wiring portion of the capacitor circuit, and the conductor pattern becomes a wiring. Here, the capacitor circuit is a parallel circuit of a Y capacitor and an X capacitor, that is, a capacitor Cxn, which is a series connection of capacitors Cyn-1 and Cyn-2, as shown in FIG. Each conductor pattern is provided with a round land to which lead wire terminals 8an, 8bn, 8cn, 8dn, 8en and 8fn protruding from the capacitors are electrically connected. In the present embodiment, the capacitor terminals and the round lands are solder-connected, so that they are reliably electrically connected with low resistance.

  The conductor pattern is fixed or positioned by being affixed to the surface of the insulating resin plate 7 via heat conductive grease or a heat conductive adhesive. As a result, a decrease in effective contact area due to minute unevenness on both contact surfaces is prevented, and a decrease in effective heat dissipation area can be prevented. The insulating resin plate 7 is preferably made of a resin having thermal conductivity.

  The second conductor portion 6 is placed on the capacitor group so as to cover the terminal surface of the capacitor group. Here, the back surface of the surface on which the conductive pattern is provided in the insulating resin plate 7 faces the terminal surface of the capacitor group. On the capacitor group, each round land portion is located at a position facing each terminal of the capacitor. Then, the capacitor terminal passes through the hole in the center of the land portion, and the portion of the capacitor terminal that protrudes from the surface of the insulating resin plate 7 provided with the conductor pattern is solder-connected to the round land portion.

  In the conductor pattern of the second conductor portion 6, the conductor pattern 6cn for electrically connecting the terminal 8en of the capacitor Cyn-1 and the terminal 8fn of the capacitor Cyn-2 and connecting the two capacitors in series is provided with rounded ends. It extends from the central part between the lands to the edge of the insulating resin plate 7, further bent at the edge of the insulating resin plate 7, and extends toward the cylindrical boss 9 bn of the cooler 9 outside the insulating resin plate 7. . A portion extending from the conductor pattern 6cn outside the insulating resin plate 7 serves as a connection terminal 6hn to the case ground. The end of the connection terminal 6hn is screwed to the cylindrical boss 9bn. Thereby, the series connection point of the capacitor Cyn-1 and the capacitor Cyn-2 is electrically connected to the case ground.

  Further, in the conductor pattern of the second conductor portion 6, the conductor pattern 6an that electrically connects the terminal 8an of the capacitor Cxn and the terminal 8cn of the capacitor Cyn-1 has a central portion between the round lands at both ends thereof. In order to establish electrical connection with the connection conductor 5an of the first conductor portion 5, the spring electrode 6en is erected. Further, the conductor pattern 6bn that electrically connects the terminal 8bn of the capacitor Cxn and the terminal 8dn of the capacitor Cyn-2 has a connection conductor 5bn of the first conductor portion 5 at the center between the round lands on both ends thereof. The spring electrode 6dn is erected to establish an electrical connection. The connection conductors 5an and 5bn of the first conductor part 5 are placed on the second conductor part 6 so as to come into contact with the spring electrodes 6en and 6dn, respectively. And electrically connected.

  The spring electrodes 6en and 6dn are made of a U-shaped conductor member, and one of the upper and lower sides (the lower sides 6gn and 6fn in FIG. 3) is fixed to the conductor patterns 6an and 6bn by soldering, respectively. So that they are electrically connected. The spring electrodes 6en and 6dn are in electrical contact with the other of the upper and lower sides (the upper side in FIG. 3) with the connection conductors 5an and 5bn of the first conductor 5, respectively, with low resistance. One of the upper and lower sides of the spring electrodes 6en and 6dn is also in contact with the surface of the insulating resin plate 7.

  The connection conductors 5an and 5bn in the first conductor portion 5 are constituted by long and thin plate-like bus bar electrodes, and are fixed to other circuit portions (not shown) or fixed to a bracket (insulating) in the mounted state. The position of the condenser cooling device is fixed by a known fixing means. At the fixed position, the plane portions of the connection conductors 5an and 5bn press the planes of the upper sides of the spring electrodes 6dn and 6en with a load that is within the allowable stress, respectively. The positions of the connection conductors 5an and 5bn with respect to the spring electrodes 6en and 6dn are fixed by the pressing force of the connection conductors 5an and 5bn and the elastic force of the spring electrodes, and the spring electrodes 6en and 6dn are low with the connection conductors 5an and 5bn, respectively. Electrical contact with resistance.

  Immediately below the electrodes of the spring electrodes 6en and 6dn, the back surface of the surface of the insulating resin plate 7 on which the conductor pattern is provided is in thermal contact with the upper surface of the extending portion 9an of the cooler 9, that is, the tip surface. In other words, the spring electrodes 6en and 6dn connected to the connection conductors 5an and 5bn and the extending portion 9an of the cooler 9 are electrically insulated by the insulating resin plate 7, but the heat of some degree through the thermal resistance. Connected. Thereby, the heat generated by the first conductor portion 5, that is, the connection conductors 5an and 5bn, is radiated to the extension portion 9an of the cooler 9 through the spring electrodes 6en and 6dn. Furthermore, in the present embodiment, the heat of the connection conductor can be radiated by the extending portion 9an of the cooler 9 and the second conductor portion 6 for constituting the capacitor circuit in the EMC filter circuit. It is not necessary to use parts. Therefore, according to the present embodiment, heat reception of the capacitor can be reliably prevented with a relatively simple configuration.

  In this embodiment, since the conductor pattern provided with the spring electrode is located on the contact surface between the cooler 9 and the second conductor portion 6, the portion adjacent to the spring electrode in the conductor pattern is the cooler. 9 and the second conductor portion 6 are located immediately above the contact surface. Further, the other of the upper and lower sides of the spring electrode is located immediately above the contact surface between the cooler 9 and the second conductor 6. By these, the effective thermal radiation area from the connection conductors 5a and 5b to the extension part 9an of the cooler 9 can be increased. Therefore, the efficiency of heat radiation from the connection conductors 5a and 5b to the extending portion 9an of the cooler 9 can be improved.

  In the present embodiment, the thermal resistance in the region from the connection conductors 5an, 5bn through the spring electrodes 6en, 6dn to the extending portion 9an of the cooler 9 is as follows. In addition, the thermal resistance of the region reaching the capacitor terminals 8an, 8bn, 8cn, and 8dn through the conductor patterns 6an and 6bn is smaller. Therefore, even if the connection conductors 5an and 5bn are connected to the conductor patterns 6an and 6bn via the spring electrodes 6en and 6dn, the amount of heat transmitted from the connection conductors 5an and 5bn to the terminals 8an, 8bn, 8cn and 8dn of the capacitor is reduced. At the same time, the heat of the connection conductors 5an and 5bn is efficiently radiated to the extending portion 9an of the cooler 9.

  Here, the noise current flowing through the capacitor group (Cxn, Cyn-1, Cyn-2) is smaller than the current flowing through the connection conductors 5an, 5bn, and is, for example, less than several amperes at the maximum. For this reason, the cross-sectional area of the conductor pattern in the 2nd conductor part 6 can be made smaller than the cross-sectional area of connection conductor 5an, 5bn. For this reason, the amount of heat conducted to the terminals of each capacitor via the conductor pattern is suppressed. The width and cross-sectional area of the conductor patterns 6an and 6bn between the spring electrodes 6en and 6dn and the capacitor terminals 8an and 8bn are smaller than the width and cross-sectional area of the spring electrodes 6en and 6dn, and the spring electrodes 6en and 6dn and the capacitor The length of the conductor patterns 6an and 6bn between the terminals 8an and 8bn is larger than the height of the spring electrodes 6en and 6dn (the length between the upper and lower sides). Accordingly, it is possible to increase the thermal resistance in the region from the connection conductors 5an, 5bn through the spring electrodes 6en, 6dn and the conductor patterns 6an, 6bn to the capacitor terminals 8an, 8bn, 8cn, 8dn. For this reason, even if the connection conductors 5an and 5bn are connected to the conductor patterns 6an and 6bn via the spring electrodes 6en and 6dn, the amount of heat transferred from the connection conductors 5an and 5bn to the terminals 8an, 8bn, 8cn and 8dn of the capacitor can be reduced. .

  Moreover, in this embodiment, the extension part 9an of the cooler 9 and the 2nd conductor part 6 contact via heat conductive grease. As a result, a decrease in effective contact area due to minute unevenness on both contact surfaces is prevented, and a decrease in effective heat dissipation area can be prevented.

  The shape of the spring electrode is not limited to the U-shape, and any other shape can be used as long as it has a flat portion that contacts the connecting conductor and a flat portion for heat dissipation and fixing on the insulating resin plate 7. good.

  Although not shown, the refrigerant flowing in the cooler 9 carries heat absorbed from the connection conductor to the heat exchanger, and the refrigerant is cooled by heat exchange and returns to the cooler 9 again. Thereby, the efficiency of heat radiation from the connection conductors 5an and 5bn to the extending portion 9an of the cooler 9 can be improved.

  As described above, according to the present embodiment, it is possible to realize a power conversion device including a cooling structure that can reliably prevent heat reception of a capacitor with a relatively simple configuration.

  In the present embodiment, the cooler 9, the capacitor group (Cxn, Cyn-1, Cyn-2), the second conductor portion 6, and the first conductor portion 5 are arranged to be stacked, The second conductor portion 6 and the connection conductors 5an and 5bn are disposed adjacent to each other. For this reason, the connection conductors 5an and 5bn and the capacitor are electrically connected via the second conductor portion 6, but an increase in the wiring length between the connection conductors 5an and 5bn and the capacitor is suppressed. An increase in inductance between 5an and 5bn and the capacitor is suppressed. Therefore, the function as the EMC filter 2 can be ensured.

  5a to 5c show a modification of the connection structure between the connection conductors 5a and 5b and the second conductor part in the first conductor part. For comparison, FIG. 5d shows a connection structure using spring electrodes 6en and 6dn in the present embodiment. 5A to 5C, members denoted by reference numerals “6′en” and “6′dn” are members that replace the spring electrodes 6en and 6dn in the present embodiment (FIGS. 3 and 4).

  In the connection structure of FIG. 5a, boss electrodes (6′en, 6′dn) are erected on a conductor pattern (not shown in FIG. 5a) provided on the surface of the insulating resin plate 7, and lead portions of the boss electrodes Are inserted through holes provided in the connecting conductors 5an and 5bn. The lead portion of the boss electrode and the connection conductors 5an and 5bn are joined to each other by solder joint or weld joint.

  In the connection structure of FIG. 5b, a boss electrode (6′en, 6 ′) in which a self-clinching fastener is embedded in a conductor pattern (not shown in FIG. 5b) provided on the surface of the insulating resin plate 7 is used. dn) is erected. Then, screws 10 (screws, bolts, etc.) inserted through holes provided in the connection conductors 5an, 5bn are passed, and the connection conductors 5an, 5bn are screwed by the screws 10 and the self fasteners 11.

  In the connection structure of FIG. 5c, boss electrodes (6'en, 6'dn) are erected on a conductor pattern (not shown in FIG. 5c) provided on the surface of the insulating resin plate 7. The connection conductors 5an and 5bn are joined to the boss electrodes (6'en and 6'dn) by pressure contact.

  Also according to these modified examples, heat generated in the connection conductors 5an and 5bn is radiated to the extending portion 9an of the cooler 9, so that heat reception of the capacitor can be prevented.

  Here, a difference from the present embodiment will be described with reference to a comparative example.

  First, as a first comparative example, the cross-sectional area of the connection conductor is increased, the resistance component of the connection conductor is reduced, the generation loss of the connection conductor is reduced, and the heat radiation area is increased by increasing the surface area of the connection conductor. There is a means.

  Here, the temperature of the connection conductor during the inverter operation can be set to an appropriate value in consideration of the maximum temperature allowable value of the resin member for supporting the connection conductor on the device case. However, when the cross-sectional area of the connection conductor is increased, it is necessary to set the temperature in consideration of a trade-off between the outer dimensions of the case that accommodates the inverter system and the increase in the weight of the inverter system. According to the study by the present inventor, the temperature of the connection conductor is set to about 130 ° C. based on such temperature setting. On the other hand, as a capacitor for constituting the EMC filter, a film capacitor is preferable in view of its frequency characteristics. The allowable element temperature (terminal temperature) of the film capacitor is a general-purpose product and is about 105 ° C. or less. Therefore, in the first comparative example, it is difficult to connect the capacitor terminal to the connection conductor.

  Next, as a second comparative example, there is means for increasing the heat radiation area by connecting the connection conductor and the capacitor terminal with a long conductor. However, since the parasitic inductance provided by the long conductor significantly reduces the filter effect of the capacitor, it is difficult to apply the second comparative example.

  As described above, according to the present embodiment, the connection conductors 5an and 5bn, the second conductor portion 6, and the cooler 9 are arranged so as to overlap each other, and the second conductor portion 6 is an extension portion of the cooler 9. Since it is in thermal contact with 9an, the heat dissipation from the connection conductors 5an and 5bn to the cooler 9 can be improved without using any special parts or members. Therefore, it is possible to reliably prevent the capacitor from receiving heat with a relatively simple configuration. In addition, according to the present embodiment, since the extending portion 9an of the cooler 9 and the X capacitor and the Y capacitor are adjacent to each other, the connection conductors 5an and 5bn, the conductor pattern, and the mutual wiring length of the X and Y capacitors are reduced. Reduced. Therefore, heat dissipation from the connection conductors 5an and 5bn to the cooler 9 can be improved without increasing the wiring inductance in the capacitor circuit.

  In addition, this invention is not limited to embodiment mentioned above, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  For example, the condenser cooling device may cool only one of the X condenser and the Y condenser.

  Further, the arrangement of the extending portions of the condenser and the cooler is not limited to the above embodiment, and other arrangements may be used.

  Moreover, the said embodiment is applicable also to inverters for industry and household appliances besides the inverter for motor vehicles. Note that the drive target load may be an AC load other than the motor.

DESCRIPTION OF SYMBOLS 1 Battery 2 EMC filter 3 Inverter 4 AC motor 5 1st conductor part 6 2nd conductor part 5a1, 5a2, 5an, 5b1, 5b2, 5bn Connection conductor 6en, 6dn Spring electrode 6gn, 6fn Lower side part 6an of spring electrode 6bn, 6cn Conductor pattern 6hn Connection terminal 7 Insulating resin plate 8a1, 8a2, 8an, 8b1, 8b2, 8bn, 8c1, 8c2, 8cn, 8d1, 8d2, 8dn, 8en, 8fn Capacitor terminal 9 Cooler 9an Extension 9bn Cylindrical boss 9cn Flat portion 10 Screw 11 Self fastener Cs Smoothing capacitor Cy1-1, Cy1-2, Cy1-n, Cy2-1, Cy2-2, Cy2-n, Cx1, Cx2, Cxn Capacitor CMC Common mode choke Du +, Dv +, Dw +, Du−, Dv−, Dw− Diode Tu , Tv +, Tw +, Tu-, Tv-, Tw- transistor

Claims (6)

An inverter;
A connection conductor for supplying power to the inverter;
A filter circuit including a capacitor circuit and mounted on the connection conductor;
In a power converter comprising:
A conductor part to which a first capacitor is electrically connected and which serves as a wiring part of the capacitor circuit;
A cooler on which the first capacitor is mounted;
With
The connection conductor, the conductor portion, and the cooler are arranged to overlap each other,
The connection conductor is electrically connected to the conductor portion;
The power converter according to claim 1, wherein the conductor portion is in thermal contact with an extension portion of the cooler. The power conversion device according to claim 1,
The power converter according to claim 1, wherein the first capacitor is adjacent to the extending portion of the cooler. The power conversion device according to claim 1,
And a second capacitor that is electrically connected to the conductor portion and forms the capacitor circuit together with the first capacitor,
The extension of the cooler is located between the first capacitor and the second capacitor;
The extension part, the first capacitor, and the second capacitor are adjacent to each other. The power conversion device according to claim 1,
The conductor portion is
An insulating plate;
A conductor pattern provided on the surface of the insulating plate and electrically connected to the connection conductor and the first capacitor;
Have
The back surface of the front surface of the insulating plate is in contact with the extended portion of the cooler. The power conversion device according to claim 4,
Thermally conductive grease is interposed between the back surface of the insulating plate and the extending portion of the cooler, or between the insulating plate and the conductor pattern. The power conversion device according to claim 1,
The power converter according to claim 1, wherein the connection conductor and the conductor portion are electrically connected by any one of pressure contact, welding, solder joint, and a spring electrode.

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