Inverter device

Abstract

An inverter device (1) comprising: two inverter circuits that convert electrical power between an n-phase AC power and a DC power, where n is a natural number; a power module (3) having a positive terminal (3P) connected to a positive electrode of a DC power supply (11) and a negative terminal (3N) connected to a negative electrode of the DC power supply (11), and forming at least one branch formed by serially connecting at least one switching component connected to the positive terminal and at least one switching component connected to the negative terminal; and a smoothing capacitor (40) connected between the positive electrode of the DC power supply (11) and the negative electrode of the DC power supply (11), comprising: an inverter housing (1B, 1C) accommodating the inverter circuits; a plate-like DC bus card (5) having a positive electrode pattern (5P) connected to the positive electrode of the DC power supply (11), a negative electrode pattern (5N) connected to the negative electrode of the DC power supply (11), and in which a positive-side terminal of the smoothing capacitor (40) is electrically connected to the positive electrode pattern (5P), a negative-side terminal of the smoothing capacitor (40) is electrically connected to the negative electrode pattern (5N), and to which the smoothing capacitor (40) is fixed; and a fixing member (7) which is a member independent of the inverter case (1B, 1C) and fixed to the inverter case (1B, 1C) and which maintains a relative positional relationship between the DC bus card (5) and a plurality of power modules (3) provided corresponding to a plurality of branches corresponding to a plurality of phases of an alternating current, wherein the positive terminal (3P) and the negative terminal (3N) of the power module (3) are provided as a DC electrode terminal pair protruding from one end on one side of the power module (3), the plurality of power modules (3) provided corresponding to the plurality of branches corresponding to the plurality of phases of the inverter current are arranged in a row along an end surface of the DC bus card (5), the two inverter circuits are formed by arranging power modules (3) on both sides of the DC bus card (5), which form each inverter circuit, when viewed in the direction perpendicular to the card surface of the DC bus card (5), the DC bus card (5) has a plurality of positive connection terminals (55P) which are electrically connected to the positive electrode pattern (5P) and which are respectively electrically connected to the positive terminals (3P) of the plurality of power modules (3), and a plurality of negative connection terminals (55N) which are electrically connected to the negative electrode pattern (5N) and which are respectively electrically connected to the negative terminals (3N) of the plurality of power modules (3), and the positive connection terminal (55P) and the positive terminal (3P), which correspond to each other, are fixed to the fixing member (7) by a common fixing member (9, 97), and the negative connection terminal (55N) and the negative terminal (3N), which correspond to each other, are fixed to the fixing member (7) by a common fixing member, so that the DC bus card (5) and the power modules (3) are fixed by the fixing member (7).

Description

TECHNICAL FIELD

[0001] The present invention relates to inverter devices that include a power module with a switching device and a smoothing capacitor, and that convert electric power between direct current (DC) power and alternating current (AC) power. TECHNICAL BACKGROUND

[0002] In recent years, hybrid vehicles and electric vehicles using a rotating electric machine as a driving power source have attracted attention to achieve energy conservation and reduction from an environmental pollution perspective. Such vehicles are provided with a DC power supply, such as a battery, that supplies electric power when the rotating electric machine functions as a driving power source and stores the electric power generated when the rotating electric machine functions as an electric generator. Since an AC rotating electric machine is often used as the rotating electric machine, an inverter device having an inverter circuit that converts electric power between DC power and AC power is mounted in such vehicles. Such an inverter device is also used in power control devices, etc.However, when such an inverter device is specifically mounted on vehicles, a size reduction of the inverter device is desirable due to weight constraints and mounting space limitations, etc. Furthermore, since the inverter circuit uses a component that generates a large amount of heat, such as a power module including a power switching component, a cooling mechanism is required to cool the inverter device. Accordingly, efforts have been made to implement an integrated device by enclosing the inverter circuit in, for example, a casing provided with cooling fins, etc., and to reduce the size and weight of the inverter device.

[0003] Japanese Patent Application Publication No. 2009-106046 (JP 2009-106046 A) (Patent Document 1) discloses an example of such an integrated inverter device. In this inverter device, a power module is placed on a flat surface in a casing having a heat-dissipating portion. A smoothing capacitor, electrically connected to the power module, is placed on a flat surface slightly below the flat surface on which the power module is placed, so that the smoothing capacitor is adjacent to the power module (seventh and eighth paragraphs, Fig. 1, etc.). A smoothing capacitor, which is required to have a high breakdown voltage and a large capacitance, tends to have a large physical size. In Patent Document 1, since the heat-dissipating area and the power module are positioned to match the height of the smoothing capacitor, the overall height of the inverter device can be reduced. However, in the housing according to this case, both the power module and the smoothing capacitor must be fixed to the housing by means of bolts, etc. Fig. For example, in Patent Document 1, the power module is fixed to the housing by bolts, and the smoothing capacitor is fixed only to the electrodes by bolts extending horizontally from the power module. Providing a separate structure for fixing the smoothing capacitor to the housing requires space for the fixing structure for both the smoothing capacitor and the housing, which may hinder the size reduction of the inverter device. [Related state-of-the-art document] JP 2005-328651 A relates to a power conversion device having a switching element that converts a direct current into a three-phase alternating current by switching. US 2008 / 0130223 A1 relates to a power converter for converting direct current power into alternating current power. [Patent document]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2009-106046 (JP 2009-106046 A) SUMMARY OF THE INVENTION [The problem to be solved by the invention]

[0005] It is therefore desirable to implement an inverter device capable of properly mounting a power module including a switching device and a smoothing capacitor in a limited area. [Means of solving the problem]

[0006] Based on the above problem, the present invention is characterized by an inverter device according to claim 1.

[0007] According to this characteristic structure, the positive connection terminals of the DC bus card on which the smoothing capacitor is mounted and the positive terminals of the power modules are fixed to the fixing member by the common fixing components. Furthermore, the negative connection terminals of the DC bus card and the negative terminals of the power modules are fixed to the fixing member by the common fixing components. The DC bus card on which the smoothing capacitor is mounted and the power modules are thus fixed to the fixing member. Therefore, the smoothing capacitor does not need to be fixed separately, and the smoothing capacitor (DC bus card) and the power modules are fixed to the fixing member using the same fixing components.The DC bus card also serves as busbars that connect the positive and negative electrodes of the DC power supply to the power modules. Accordingly, an inverter circuit can be formed in a relatively small area. According to this characteristic structure, an inverter device can be implemented that can properly fix a power module, including a switching component and a smoothing capacitor, in a limited region.

[0008] In the inverter device according to the present invention, the positive terminal and the negative terminal of the power module are provided as a pair of DC electrode terminals protruding from one end on one side of the power module. According to this structure, the connection areas with the DC bus card can be located along the end (edge) on one side of each power module. The positive connection terminal and the negative connection terminal of the DC bus card can thus be arranged side by side, thereby simplifying the structure of the DC bus card.

[0009] In the inverter device according to the present invention, the DC bus card preferably includes a pair of DC electrode pattern connection terminals electrically connected to the positive electrode pattern and the negative electrode pattern. The fixing member preferably includes a pair of DC power supply connection terminals electrically connected to the positive electrode and the negative electrode of the DC power supply, and a pair of DC bus card connection terminals electrically connected to the pair of DC power supply terminals. The pair of DC electrode pattern connection terminals of the DC bus card is preferably fixed to the pair of DC bus card connection terminals by a fixing member. Typically, the DC power supply is provided separately from the inverter device, and the DC power is supplied from outside the inverter device.On the other hand, it is preferable that the DC bus card and the power modules are integrated into a single package from the perspective of insulation properties and cooling capabilities. Since the fixing member includes the DC power supply connection terminal pair and the DC bus card connection terminal pair, and both terminal pairs are electrically connected to each other, the interior of the inverter device can be sufficiently separated from its exterior, and a required electrical connection can be ensured between the DC power supply and the inverter device.

[0010] In the inverter device according to the present invention, it is preferably provided that a first electrode pattern as one of the positive electrode pattern and the negative electrode pattern is formed on a first card surface of the DC bus card as one surface of an insulating layer constituting a substrate, and a second electrode pattern as the other of the positive electrode pattern and the negative electrode pattern is formed on a second card surface of the DC bus card as the other surface of the insulating layer. Each terminal of the DC bus card is fixed by the fixing member such that the first card surface contacts terminals provided on the other components. The terminal electrically connected to the second electrode pattern has a connection pad formed on the first card surface so as to be separated from the first electrode pattern.and a conductive through-hole extending through the insulation layer and formed separately from a fixing component through-hole through which the fixing component extends, the conductive through-hole having a conductive material on its inner wall, and the second electrode pattern being electrically connected to the connection pad through the conductive material.

[0011] Bolts made of a conductive material such as iron are often used as fastening components. When a current flows between the first and second card surfaces of the DC bus card, a current also flows in the fastening components, which can increase the temperature of the terminals (DC electrode terminal pair) of the power modules and their surroundings due to the heat generated by the fastening components. In the case where the conductive through-hole having the conductive material on its inner wall is provided separately from the fastening component through-hole as described above, most of the current flows between the first and second card surfaces of the DC bus card via the conductive through-hole, which has a lower impedance. This suppresses the current flowing in the fastening components and can suppress heat generation of the fastening components.Providing the conductive through-hole in this way enables the use of non-conductive components (made of resin, etc.) as mounting components. Accordingly, flexibility in component selection is improved. Resin components are typically lighter than iron components, thus contributing to a weight reduction of the inverter device.

[0012] In the inverter device according to the present invention, it is preferable that the power modules are provided on both sides of the smoothing capacitor, as viewed in a direction perpendicular to a card surface of the DC bus card. Power modules in which a high current flows often have a cooling mechanism, such as a metal heat sink, and are therefore relatively heavy. Disposing the power modules on both sides of the smoothing capacitor allows the fixing member to have a structure that is supported on both sides instead of only one side when the power modules are fixed to the fixing member. This reduces the stress applied to the fixing member.

[0013] In the inverter device according to the present invention, it is preferable that the smoothing capacitor is formed by parallel connection of a plurality of capacitor components, the number of capacitor components is at least equal to that of the power modules, and the capacitor components are arranged to have a positional relationship corresponding to that of the power modules. Since the smoothing capacitor is formed by the plurality of capacitor components, the capacitance of each capacitor component is reduced to the desired capacitance of the smoothing capacitor. This can reduce the size of the capacitor components. Accordingly, the layout flexibility of the smoothing capacitor is increased, and the smoothing capacitor can be accommodated in a relatively small space.Because the smoothing capacitors are evenly arranged and distributed close to the power module's periphery, the inductance of the power supply line is reduced, and a high smoothing effect can be achieved with low loss. Voltage surges, etc., can also be reduced.

[0014] In the inverter device according to the present invention, it is preferable that the smoothing capacitor is formed by connecting the plurality of capacitor components in parallel, the number of capacitor components may correspond to that of the power modules, and the capacitor components are arranged to have a positional relationship corresponding to that of the power modules. In this case, it is preferable that the inverter device further comprises: a control board that is positioned to cover the power modules and the DC bus board when viewed in a direction perpendicular to the board surface of the DC bus board, and that controls the two inverter circuits; and the inverter case that houses the DC bus board, the power modules, and the fixing component, and that has at least (n-1) brackets that support and fix the control board at a central portion of the control board.Preferably, the DC bus card of the inverter device has support through-holes through which the supports extend, and each support through-hole is provided between the phases of the capacitor components arranged to correspond to the power modules arranged in a row along one end surface of the DC bus card and forming the n-phase branches.

[0015] The control board, which is positioned to cover the power modules and the DC bus board when viewed in a direction perpendicular to the board surface of the DC bus board, is a substrate that has a relatively large area. This can cause distortion (warping), vibration, etc. of the control board. However, the inverter casing is provided with the supports that support and fix the control board in the central area of ​​the control board. This suppresses distortion (warping), vibration, etc. of the control board. The DC bus board is positioned to overlap the central area of ​​the control board when viewed in a direction perpendicular to the board surfaces of the control board and the DC bus board. Accordingly, the support through-holes through which the supports that fix and support the control board extend are formed in the DC bus board.Each support through-hole is provided between the phases of the capacitor components, which are arranged and distributed to correspond to the power modules that form the branches of each phase. Accordingly, the layout flexibility of the capacitor components acting as smoothing capacitors is not compromised, and the capacitor components can be evenly arranged and distributed close to the surroundings of each power module. Furthermore, distortion (strain) and vibration of the control board can be sufficiently suppressed. BRIEF DESCRIPTION OF THE DRAWINGS [ Fig. 1] Fig. 1 shows an exploded perspective view of an inverter box. [ Fig. 2] Fig. Figure 2 shows a perspective view showing the appearance of the inverter box. [ Fig. 3] Fig. 3 is a schematic circuit diagram showing the system configuration of a driving device of a rotating electrical machine. [ Fig. 4] Fig. Figure 4 shows a schematic circuit diagram showing the structure of the inverter box. [ Fig. 5] Fig. 5 shows an enlarged partial view of the exploded perspective view. [ Fig. 6] Fig. 6 shows a perspective view of a fixing component. [ Fig. 7] Fig. 7 is a diagram showing an electrode pattern on a component mounting surface of a DC bus card. [ Fig. 8] Fig. Figure 8 is a diagram showing an electrode pattern on a soldering pad of the DC bus board. [ Fig. 9] Fig. 9 shows a partial cross-sectional view of an interconnect pad and a region near the conductive vias of the DC bus card. EMBODIMENTS OF THE INVENTION

[0016] An embodiment of the present invention will be described based on the accompanying drawings with respect to an example in which the present invention is applied to an inverter device mounted on a driving device of a rotating electrical machine for use in hybrid vehicles, electric vehicles, etc. In the present embodiment, as shown in the Fig. 1 and Fig. As shown in Figure 2, an inverter device 1 is provided in the form of an inverter box 1A having a circuit board (circuit card), etc. The inverter box 1A has two housings (inverter housings). One of the housings is a base housing 1B, to which various components constituting the inverter circuits 10 are mounted, as shown in Figures Fig. 3 and Fig. 4, and a control board 8 that controls the inverter circuits 10 are mounted. The other housing is a cover housing 1C that contacts the base housing 1B to enclose the inverter circuits 10 and the control board 8 mounted on the base housing 1B. The inverter box 1A (inverter device 1) is formed by enclosing the circuit board, etc., with the base housing 1B and the cover housing 1C as an inverter housing.

[0017] A vehicle according to the present embodiment is, for example, a hybrid vehicle of the 2-engine split type or an electric vehicle (or hybrid vehicle) of the “in-wheel” or “in-wheel” engine type, as in Fig. 3, and has two rotating electric machines MG (MG1, MG2) mounted thereon. A two-motor split-type hybrid vehicle, for example, has an internal combustion engine and a pair of rotating electric machines (not shown) as driving power sources. A drive device for this hybrid vehicle includes a power transmission differential gear unit (not shown) that distributes an output of the internal combustion engine to one of the rotating electric machines and to wheels and the other rotating electric machine. The in-wheel motor type electric vehicle (hybrid vehicle), for example, has rotating electric machines as driving power sources in a pair of right and left drive wheels, or has rotating electric machines as driving power sources in a power transmission mechanism directly coupled to the drive wheels.Accordingly, in the present embodiment, the inverter box 1A (inverter device 1) is configured as a device that drives the two rotating electric machines MG (MG1, MG2). These rotating electric machines MG (MG1, MG2) serve either as an electric motor or as an electric generator, as needed. Thus, these rotating electric machines MG (MG1, MG2) can perform both power running and regenerative running. These two rotating electric machines MG (MG1, MG2) will be referred to simply as "rotating electric machines MG" hereinafter unless specifically indicated.

[0018] Fig. 3 shows a system configuration of the drive device of a rotating electrical machine. As shown in Fig. As shown in FIG. 3, the rotating electric machine drive device includes two inverter circuits 10, namely, a first inverter circuit 10A that drives one of the rotating electric machines MG (first rotating electric machine MG1) and a second inverter circuit 10B that drives the other rotating electric machine MG (second rotating electric machine MG2). The rotating electric machine drive device further includes a smoothing capacitor 40 that smooths a system voltage Vdc as a voltage on the DC side of the inverter circuits 10. The inverter circuits 10 (10A, 10B) and the smoothing capacitor 40 are arranged in the inverter box 1A.

[0019] As exemplified in Fig. As shown in Figure 3, the driving device of the rotating electrical machine sometimes includes a common single converter circuit 18 for the two inverter circuits 10 (10A, 10B). This converter circuit 18 converts DC power (direct voltage) between the common system voltage Vdc for the two inverter circuits 10 (10A, 10B) and a voltage of a battery 11. In this case, the system voltage Vdc is an output voltage (boost-side output voltage) of the converter circuit 18. When the boost ratio is equal to "1", the output voltage of the converter circuit 18 is substantially equal to the voltage between the terminals of the battery 11. In the exemplary embodiment shown in Fig. In the configuration shown in Figure 3, the battery 11 and the converter circuit 18 serve as a "DC power supply" of the inverter device 1. When the drive device of the rotating electric machine does not include the converter circuit 18, the battery 11 serves as the "DC power supply." The smoothing capacitor 40 is connected between a positive electrode P and a negative electrode N of the thus-defined "DC power supply," regardless of whether the drive circuit of the rotating electric machine includes the converter circuit 18 or not, and smoothes the voltage between the positive and negative electrodes of the "DC power supply" (system voltage Vdc).

[0020] The battery 11 can supply electric power to the rotating electric machines MG (MG1, MG2) via the two inverter circuits 10 (10A, 10B) and can store electric power generated by the rotating electric machines MG (MG1, MG2) via the two inverter circuits 10 (10A, 10B). Various secondary batteries (storage batteries), such as nickel-metal hydride batteries, lithium-ion batteries, capacitors, combinations thereof, etc., can be used as such a battery 11.

[0021] The inverter circuits 10 (10A, 10B) are circuits that convert DC power having a system voltage Vdc into AC power having a plurality of phases (n-phases, where n represents a natural number, three phases in this example) and supply the AC power to the rotating electrical machines MG (MG1, MG2). They also convert the AC power generated by the rotating electrical machines MG (MG1, MG2) into DC power and supply the DC power to the DC power supply. These two inverter circuits 10 (10A, 10B) are hereinafter referred to simply as "inverter circuits 10" unless specifically indicated. Each of the inverter circuits 10 has a plurality of switching components. Insulated gate bipolar transistors (IGBTs) or power metal-oxide-semiconductor field-effect transistors (power MOSFETs) are preferred as switching components. As described in Fig. 3, IGBTs 30 are used as switching components in this embodiment.

[0022] For example, each of the inverter circuits 10 that converts electrical power between DC power and three-phase AC power is formed by a bridge circuit having three branches corresponding to the three phases, which is generally known. As shown in the Fig. 3 and Fig. Thus, as shown in Figure 4, two IGBTs 30 are connected in series between the positive DC electrode side (positive electrode side P of the DC power supply) and the negative DC electrode side (negative electrode side N of the DC power supply) of the inverter circuit 10 to form a single arm 10L. Three (three phases: 10U, 10V, 10W) ​​of these series circuits (arms 10L) are connected in parallel. Thus, a bridge circuit is formed, which includes three series circuits (arms 10L) corresponding to the stator coils of the U-phase, V-phase, and W-phase of the rotating electric machine MG. The IGBT 30 in the upper stage of each phase has its collector connected to the positive electrode P of the DC power supply, and its emitter connected to the collector of the IGBT 30 in the lower stage of that phase.The IGBT 30 in the lower stage of each phase has its emitter connected to the negative electrode N of the DC power supply (e.g., ground). An intermediate point in the series circuit (branch 10L) of the pair of IGBTs 30 of each phase, i.e., the connection point between the IGBTs 30, is connected to a corresponding one of the stator coils of the rotating electric machine MG.

[0023] Freewheeling diodes (regeneration diodes) are connected in parallel with each of the IGBTs 30. Each freewheeling diode is connected in parallel with a corresponding one of the IGBTs 30 such that its cathode terminal is connected to the collector terminal of the IGBT 30 and its anode terminal is connected to the emitter terminal of the IGBT 30.

[0024] In the present embodiment, as shown in Fig. 4, each branch 10L, in which the IGBTs 30 are connected in series together with the freewheeling diodes, is formed as a power module 3. As shown in the Fig. 4 and Fig. As shown in Figure 5, each power module 3 has a positive terminal 3P connected to the positive electrode P of the DC power supply and a negative terminal 3N connected to the negative electrode N of the DC power supply. Thus, each power module 3 is configured by at least one branch 10L formed by a series connection of at least one IGBT 30 connected to the positive terminal 3P and at least one IGBT 30 connected to the negative terminal 3N. Each inverter circuit 10, which converts electrical power between DC power and three-phase AC power, is formed by connecting three power modules 3 in parallel. As shown in Figure 5, Fig. 5, the positive terminal 3P and the negative terminal 3N are provided as a DC electrode terminal pair 3T projecting from one end 35 on one side of the power module 3.

[0025] As in Fig. As shown in Figure 3, the inverter circuits 10 are controlled by a control device 80. The control device 80 includes an electronic control unit (ECU) and a driver circuit. Part or all of the circuits constituting the control device 80 are mounted on the control board (see Fig. 1). The ECU mounted on the control device 80 is configured using a logic circuit such as a microprocessor as a core component. In the present embodiment, the ECU controls the rotating electrical machines MG via the inverter circuits 10 by performing current feedback control (closed-loop control) using a vector control method. The ECU has various functional units for current feedback control, and each functional unit is implemented through an interaction between hardware such as a microcomputer and software (program).

[0026] The IGBTs 30 constituting each inverter circuit 10 have their gate terminals connected to the ECU via the driver circuit and are individually turned on / off. Typically, the operating voltage (power supply voltage of a circuit) varies significantly between an electric power circuit that drives the rotating electric machine MG and an electronic circuit, such as the ECU, which uses the microcomputer as its core. Accordingly, a control signal for the IGBT 30 generated by the ECU is supplied at a relatively low voltage to the inverter circuit 10 via the driver circuit as a high-voltage gate drive signal S.Similarly, in the case where the converter circuit 18 is mounted on the driving device of the rotating electrical machine, a high-voltage converter gate drive signal S10 is supplied from the control device 80 to the converter circuit 18 via the driver circuit.

[0027] An actual current flowing in the coils of each phase of the rotating electric machine MG is detected by a current sensor 12, and the control device 80 obtains the detection result. Fig. Figure 3 schematically shows a form in which a contactless current sensor 12, arranged near the busbars, etc., is used to detect a current in a contactless manner as the actual current of each of the three phases. The current sensor 12 is connected to a third terminal block 93, as described below (see Fig. 1 and Fig. 4) and detects a current flowing in the bus bars extending into the third terminal block 93. As shown in Fig. As shown in FIG. 1, a current detection result output connector 9S is provided on the third terminal block 93 and is connected to a current detection result input connector 82 of the control board 8 through a cable (not shown). The present embodiment shows a configuration in which currents of all three phases are detected. However, the three phases are in a balanced state, and the sum of the instantaneous values ​​of the currents is zero. Accordingly, currents of only two phases can be detected by the current sensor 12, and a current of the remaining one phase can be obtained by calculation in the control device 80.

[0028] The magnetic pole position of a rotor of the rotating electric machine MG is detected at any time by a rotation sensor 13, and the control device 80 obtains the detection result. The rotation sensor 13 is formed by, for example, a resolver, etc. The magnetic pole position represents a rotation angle of the rotor in an electrical angle. As shown in Fig. As shown in FIG. 3, the rotation sensor 13 is placed near the rotating electrical machine MG. Thus, the detection result of the rotation sensor 13 is transmitted to the control device 80 via a cable (not shown). When the ECU using the detection result of the rotation sensor 13 is formed on the control board 8, the detection result of the rotation sensor 13 is sent to the control device 80 via an external connector 83 placed on the control board 8 to transmit and receive signals to and from the surroundings of the inverter box 1A. A target torque TM (TM1, TM2) of the rotating electrical machine MG provided to the control device 80 as a request signal from another control device, such as a vehicle control device (not shown), is also sent via the external connector 83.

[0029] As in Fig. As shown in FIG. 1, the control board 8 constituting the control device 80 has signal transmission through-holes 81 (signal transmission terminal receiving portions) for transmitting and receiving signals including the gate drive signal S to and from the power modules 3. When the power modules 3 and the control board 8 are mounted on the base case 1B, the signal transmission contacts 31 (signal transmission terminals) of the power modules 3 extend through the signal transmission through-holes 81. The signal transmission contacts 31 are soldered to the signal transmission through-holes 81, allowing signals to be transmitted between the control board 8 and each power module 3. The signals transmitted between the control board 8 and each power module 3 include, in addition to the gate drive signal S described above, a fault diagnosis signal, a temperature detection signal, etc.from the power module 3 to the control card 8.

[0030] As in the Fig. 1, the inverter box 1A is formed by attaching the power modules 3 to a DC bus board 5 having the smoothing capacitor 40 mounted thereon, the terminal blocks having a first terminal block 7 (fixing member) (second terminal block 92 and third terminal block 93), and the control board 8 to the base case 1B, and by attaching the cover case IC to the base case 1B so as to enclose these components. The DC bus board 5 and the first terminal block 7 (fixing member) are common components for the two inverter circuits 10 (10A, 10B). The second terminal block 92 and the third terminal block 93 are provided for each of the first rotating electrical machine MG1 (first inverter circuit 10A) and the second rotating electrical machine MG2 (second inverter circuit 10B).Thus, a second first rotating electric machine terminal block 92A and a third first rotating electric machine terminal block 93A are provided for the first rotating electric machine MG1, and a second second rotating electric machine terminal block 92B and a third second rotating electric machine terminal block 93B are provided for the second rotating electric machine MG2.

[0031] As described above, the current sensor 12 is attached to the third terminal block 93. The detection result of the current detected in the third terminal block 93A of the first rotating electrical machine is transmitted to the second device 80 via a cable, etc., not shown, connecting the current detection result output connector 9S and a current detection result input connector 82A of the control board 8 for the first rotating electrical machine. Similarly, the detection result of the current detected in the third terminal block 93B of the second rotating electrical machine is transmitted to the control device 80 via a cable, etc., not shown, connecting the current detection result output connector 9S and the current detection result input connector 82B of the control board 8 for the second rotating electrical machine.

[0032] As in Fig. As shown in FIG. 5, the first terminal block 7 has threaded holes 71 for receiving fastening members 97 (9) extending through the fastening member through-holes 57 formed in the DC bus card 5 and through holes formed in the DC electrode terminal pair 3T of the power modules 3. The base case 1B has threaded holes 17a for receiving the fastening members 95 (9) extending through the through-holes 72 formed in the first terminal block 7. In this way, the DC bus card 5 and the power modules 3 are fastened to the first terminal block 7 by the common fastening members 9, and the first terminal block 7 is fixed to the base case 1B.The first terminal block 7 serves as a fixing member that maintains a relative positional relationship between the DC bus card 5 and the plurality of power modules 3 provided corresponding to the branches 10L corresponding to the plurality of phases of the alternating current.

[0033] In addition to the terminal pairs (pairs of “55P” and “55N” as shown below based on Fig. 7) that contact the DC electrode terminal pairs 3T of the power modules 3 in such a way that they are electrically connected thereto, is a DC electrode pattern connection terminal pair 56T (see Fig. 5 and Fig. 7) connected to the DC power supply is formed on a first card surface 51 of the DC bus card 5. The DC electrode pattern connection terminal pair 56T is connected to a DC bus card connection terminal pair 76T formed on the first terminal block 7, as shown in Fig. 6, in a perspective view viewed from a direction away from the Fig. 1 and Fig. 5 different directions. The DC bus card 5 is thus attached to the base housing 1B by means of fastening components 96 (9), as shown in Fig. 5, so that the DC electrode pattern connection terminal pair 56T of the DC bus card 5 contacts the DC bus card connection terminal pair 76T of the first terminal block 7. As shown in Fig. As shown in Figure 6, the first terminal block 7 has a DC power supply connection terminal pair 75T that is electrically connected to the DC bus card connection terminal pair 76T. The DC power supply connection terminal pair 75T has terminals that are connected to the positive electrode P and the negative electrode N of the DC power supply, for example, the battery 11, which is placed outside the inverter box 1A. As shown in Fig. As shown in Figure 2, the DC power supply connection terminal pair 75T is placed outside the inverter box 1A, even in the state where the cover case 1C is attached to the base case 1B. Thus, the DC power supply connection terminal pair 75T can be easily connected to the DC power supply.

[0034] As in the Fig. 7 to 9, a first electrode pattern 51E as one of a positive electrode pattern 5P and a negative electrode pattern 5N is formed on the first card surface 51 of the DC bus card 5, which is one of the surfaces of an insulating film 53 formed on the substrate 50, and a second electrode pattern 52E as the other of the positive electrode pattern 5P and the negative electrode pattern 5N is formed on a second card surface 52 of the DC bus card 5, which is the other surface of the insulating film 53. In the Fig. In the example shown in Figures 7 to 9, the negative electrode pattern 5N is formed as the first electrode pattern 51E on the first card surface 51, and the positive electrode pattern 5P is formed as the second electrode pattern 52E on the second card surface 52. Electrode patterns of different polarities are formed on the card surfaces. These electrode patterns thus cause direct current to flow in opposite directions on these card surfaces. Electromagnetic induction is thus canceled out, and mutual inductance is increased. This suppresses voltage surges and reduces losses.

[0035] The positive electrode pattern 5P and the negative electrode pattern 5N, in which a large current flows, have a greater thickness than an electrode layer on a normal printed circuit board, and preferably a thickness of, for example, approximately 300 to 600 [µm]. The electrode pattern diagrams of the Fig. 7 and Fig. 8 show diagrams when viewed in the same direction, and one of the electrode pattern diagrams is a top view, the other is a through view. Specifically, Fig. 8 is a diagram of the DC bus card 5, viewed directly from the second card surface 52 (the soldering surface described below) (a front view of the second card surface 52), and Fig. 7 shows a diagram of the first card surface 51 of the DC bus card 5 as a transparent view seen from the side of the second card surface 52 (a transparent view of the first card surface 51).

[0036] As in Fig. As shown in Fig. 7, each terminal of the DC bus card 5, specifically the positive connection terminals 55P, the negative connection terminals 55N, and the DC electrode pattern connection terminal pair 56T, is formed on the first card surface 51 of the DC bus card 5. The DC bus card 5 is fixed to the first terminal block 7 by the fixing members 9 such that the first card surface 51 contacts the terminals provided on the other components, such as the power modules 3 and the first terminal block 7. In other words, the DC bus card 5 is fixed to the base case 1B via the first terminal block 7 by the fixing members 9 such that the terminals provided on the first card surface 51 contact the terminals provided on the other components.

[0037] Since the surface that contacts the terminals provided on the other components is the first board surface 51, the positive electrode pattern 5P formed as the second electrode pattern 52E on the second board surface 52 must be partially formed on the first board surface 51. The terminals (positive connection terminals 55P) that are electrically connected to the second electrode pattern 52E (positive electrode pattern 5P) are formed on the first board surface 51. As shown in the Fig. 7 and Fig. As shown in Figure 9, each of these terminals (positive connection terminals 55P) has a connection pad 5C formed on the first card surface 51 so as to be separated from the first electrode pattern 51E (negative electrode pattern 5N), and conductive vias 5H extending through the insulating layer 53. The conductive vias 5H are formed separately from the fixing member via 57 in the positive connection terminal 55P, through which the fixing member 9 extends. Each conductive via 5H has a conductive material E on its inner wall; the second electrode pattern 52E (positive electrode pattern 5P) is electrically connected to the connection pad 5C through the conductive material 5E. Fig. 9 shows a section along the line IX-IX in Fig. 7 in the state in which the DC bus card 5 together with the power modules 3 is fixed to the first terminal block 7 by the fixing components 9 (97).

[0038] Electrodes other than the positive connection terminals 55P, generally the negative connection terminals 55N, and the DC electrode pattern connection terminal pair 56T are insulated by coating the board surfaces with resin, etc. However, the conductive through-holes 5H are not subjected to any insulation treatment, so the conductive through-holes 5H are filled with solder in a flow process described below. Filling the conductive through-holes 5H with solder increases a cross-sectional area of ​​the electrical connection and can reduce the impedance between the first board surface 51 and the second board surface 52.

[0039] Bolts made of a conductive metal such as iron, etc., are often used as the fastening components 9. When a current flows between the first board surface 51 and the second board surface 52 of the DC bus board 5, the current also flows in the fastening components 9, which increases the temperature of the terminals (DC electrode terminal pairs 3T) of the power modules 3 and their surroundings due to the heat generated by the fastening components 9. In the case where the conductive through-holes 5H having the conductive material E on their inner walls are provided separately from the fastening component through-holes as described above, most of the current flows between the first board surface 51 and the second board surface 52 of the DC bus board 5 via the conductive through-holes 5H having low impedance.This suppresses the current flowing in the fastening components 9 and can prevent heat generation of the fastening components 9. Providing the conductive through-holes 5H in this manner allows non-conductive components (made of resin, etc.) to be used as the fastening components 9. Accordingly, flexibility in component selection is improved. Resin components are typically lighter than iron components, and thus contribute to a weight reduction of the inverter box 1A.

[0040] The conductive material E may be provided on the inner walls of the fastening component through-holes 57 by plating, etc., or the conductive material E may not be provided on the inner walls of the fastening component through-holes 57. In the Fig. 9, the conductive material E is not provided on the inner walls of the fixing member through-holes 57. Although the Fig. 7 to 9 show an example in which the negative electrode pattern 5N is formed as the first electrode pattern 51E on the first card surface 51, and the positive electrode pattern 5P is formed as the second electrode pattern 52E on the second card surface 52, the positive electrode pattern 5P may be formed as the first electrode pattern 51E and the negative electrode pattern 5N as the second electrode pattern 52E.

[0041] As in the Fig. 1, Fig. 4, Fig. 5 etc., the smoothing capacitor 40 is formed by connecting a plurality of capacitor components 4 in parallel. The number of capacitor components 4 corresponds to that of the power modules 3, and the capacitor components 4 are arranged and distributed such that they have a positional relationship corresponding to that of the power modules 3. As shown in Fig. 1, the power modules 3 are placed on both sides of the smoothing capacitor 40 (capacitor component group) when viewed in a direction perpendicular to the board surface of the DC bus board 5. Specifically, the plurality of power modules 3 provided corresponding to the branches 10L corresponding to the plurality of phases of the alternating current are arranged in a row along one end surface 5L of the DC bus board 5. In the present embodiment, since the two inverter circuits 10 (10A, 10B) are formed, the power modules 3 are arranged in a row along opposite two end surfaces 5L, respectively. The number of capacitor components 4 corresponds to the number of power modules 3. For example, one or more capacitor components 4 are provided for each power module 3.The number of capacitor components 4 is the same as that of power modules 3, or is equal to the number of power modules 3 multiplied by a natural number. The capacitor components 4 are arranged to have a positional relationship corresponding to that of the power modules 3. For example, the capacitor components 4 are placed near each power module 3.

[0042] Specifically, in each power module connection terminal pair 55T as a pair of a positive connection terminal 55P and a negative connection terminal 55N, the capacitor component 4 is placed to have an arrangement distance (capacitor arrangement distance) such that the distance between the capacitor component 4 and the positive connection terminal 55P is equal to (substantially equal to) that between the capacitor component 4 and the negative connection terminal 55N. The capacitor components 4 are arranged and distributed such that the capacitor arrangement distances for all power modules are equal to each other (substantially equal). In the case where a plurality of capacitor components 4 are assigned to each power module 3 (each power module connection terminal pair 55T), the distances to the positive connection terminal 55P and the distances to the negative connection terminal 55N are preferably average values.As a result, when the capacitor components 4 are arranged in this manner, the capacitor components 4 are located close to each power module 3. This reduces the impedance (especially an inductive component) of each power module 3 (each branch 10L) to the DC power supply, and can sufficiently suppress a surge voltage generated by switching the IGBT 30.

[0043] A discharge resistor R (see Fig. 4) is often connected in parallel with the smoothing capacitor 40 to discharge the remaining charge when the driving device of the rotating electrical machine is turned off. This discharge resistor R can also be mounted on the DC bus board 5. The discharge resistor R and its fixing mechanism do not need to be placed elsewhere in the inverter box 1A, and size reduction can be achieved. As described above, the DC electrode pattern connection terminal pair 56T, which is electrically connected to the DC bus board connection terminal pair 76T, which is electrically connected to the DC power supply connection terminal pair 75T, which is electrically connected to the external DC power supply, is formed on the DC bus board 5. The discharge resistor R is preferably placed near the DC electrode pattern connection terminal pair 56, for example, so as to be adjacent to this terminal pair.The discharge resistor R can also be formed by a parallel connection of a plurality of smaller resistance components (not shown) having low current capacity.

[0044] The first card area 51 of the DC bus card 5 is a component area on which the majority of the capacitor components 4 and the resistor components are mounted. Fig. 7 and Fig. The example shown in Fig. 8 shows a shape in which only the capacitor components 4 are mounted thereon. The capacitor components 4 are, for example, electric field capacitors. In the present embodiment, the capacitor components 4 are radially discrete components. In this case, although the capacitor components 4 are mounted on the first board surface 51 as a component surface, lead wires serving as terminals of the capacitor components 4 extend to the second board surface 52 side through the through-holes formed in the DC bus board 5. The lead wires of the capacitor components 4 are soldered to the second board surface 52. The second board surface 52 is thus a soldering surface on which soldering is performed.

[0045] This soldering is often performed by a flow process in which the DC bus board 5 is moved such that the soldering surface extends along a liquid surface of a solder bath filled with molten solder. The lead wires of the capacitor components 4 mounted on the component surface protrude beyond the soldering surface via the through-holes. The lead wires protruding beyond the soldering surface are soldered to lands (conductive material E) formed around the through-holes and the conductive material E formed on the inner walls of the through-holes. At this time, no solder adheres to the conductive material E (the lands, the through-holes, etc.), which is insulated by resin, etc.As described above, the conductive through-holes 5H are not subjected to an insulation treatment such as resin treatment, so that the solder can be guided toward the first card surface 51 (component surface) via the conductive through-holes 5H by utilizing the capillary effect in the flow process, and the conductive through-holes 5H can be filled with solder.

[0046] The through-holes into which the lead wires of the capacitor component 4 are inserted are also subjected to an insulation treatment, such as a resin treatment, and thus, solder is guided toward the first board surface 51 by capillarity via the through-holes and the lead wires. When an appropriate amount of solder is guided to the first board surface 51, the lead wires are soldered to both surfaces of the DC bus board 5. Accordingly, a mechanical connection is obtained, and electrically reliable assembly is implemented. The lead wire connecting lands (electrode patterns) formed in the first electrode pattern 51E (negative electrode pattern 5N) on the first board surface 51 have a larger area than themselves, so that solder can solidify before reaching the first board surface 51 due to heat dissipation.Accordingly, the solder cannot be sufficiently moved to the first card surface 51. Therefore, it is preferable that these lands be shaped such that the conductive material E is partially omitted, as indicated by reference numeral "54N" in FIG. Fig. 7 shown.

[0047] During the reflow process, the DC bus board 5 is brought into contact with molten solder having a temperature of 200°C or higher, and consequently, the temperature of the DC bus board 5 also increases. If the capacitor components 4 are electric field capacitors, their outer casings (cans) may partially melt, and their insulation properties may deteriorate. In the form in which the negative electrode pattern 5N is formed on the component surface (first board surface 51), the polarity (negative electrode N) of the cans is the same as that of the negative electrode pattern 5N. Accordingly, reliability is not reduced even if the insulation properties deteriorate.

[0048] As in the Fig. 7 and Fig. As shown in Figure 8, the DC bus card 5 has the positive connection terminals 55P, which are electrically connected to the positive electrode pattern 5P, and the negative connection terminals 5N, which are electrically connected to the negative electrode pattern 5N. The positive connection terminal 5P is a terminal to be electrically connected to the positive terminal 3P of the power module 3 when the inverter box 1A is assembled as shown in Figures Fig. 1 and Fig. 5. Similarly, the negative connection terminal 55N is a terminal to be electrically connected to the negative terminal 3N of the power module 3. The DC bus card 5 has a plurality of positive connection terminals 55N that are electrically connected to the positive electrode pattern 5P and are respectively electrically connected to the positive terminals 3P of the plurality of power modules 3, and a plurality of negative connection terminals 55N that are electrically connected to the negative electrode pattern 5N and are respectively electrically connected to the negative terminals 3N of the plurality of power modules 3.

[0049] The positive connection terminal 55N and the positive terminal 3P, which correspond to each other, are fixed to the first terminal block 7 (fixing member) by a common fixing member 97 (9), and the negative connection terminal 55N and the negative terminal 3N, which correspond to each other, are fixed to the first terminal block 7 (fixing member) by a common fixing member 97 (9), so that the DC bus card 5 and the power modules 3 are fixed to the first terminal block 7 (fixing member). Specifically, the positive connection terminals 55P of the DC bus card 5 and the positive terminals 3P of the power modules 3 are fixed to the first terminal block 7 (fixing member) by the common fixing members 97 (9).Similarly, the negative connection terminals 55N of the DC bus card 5 and the negative terminals 3N of the power modules 3 are fixed to the first terminal block 7 (fixing member) by the common fixing members 97 (9). The DC bus card 5 and the power modules 3 are thus fixed to the first terminal block 7 (fixing member). The positive terminal 3P and the negative terminal 3N of each power module 3 are provided as a DC electrode terminal pair 3T protruding from the end 35 on one side of the power module 3. Each power module 3 is fixed such that the end 35 on one side faces the first terminal block 7 (fixing member).

[0050] The DC electrode pattern connection terminal pair 56T formed on the DC bus card 5 is fixed to the first terminal block 7 by the fixing members 96 (9) so as to be in contact with the DC bus card connection terminal pair 76T of the first terminal block 7. As shown in the Fig. 1 and Fig. As shown in Fig. 5, when each power module 3 is directly fixed to the base case 1B by a fixing member 94 (9), the power module 3 is further fixed. Since each power module 3 can be formed to better contact the base case 1B, the power module 3 can be cooled via the base case 1B. It is preferable, for example, that the base case 1B has cooling fins on the surface opposite to the surface contacting the power modules 3. The power modules 3 can be sufficiently cooled by using the base case 1B as a heat sink.

[0051] As in the Fig. 1, Fig. 3 and Fig. As shown in FIG. 4, the inverter box 1A according to the present embodiment includes two inverter circuits 10 (10A, 10B) that convert electric power between three-phase AC power and DC power. The inverter box 1A is formed by placing the power modules 3 of the inverter circuits 10 (10A, 10B) on the respective sides of the DC bus board 5, as viewed in the direction perpendicular to the board surface of the DC bus board 5. The control board 8, on which part or all of the circuits of the control device 80 for controlling the two inverter circuits 10 (10A, 10B) are provided, is placed so as to cover the power modules 3 and the DC bus board 5, as viewed in the direction perpendicular to the board surface of the DC bus board 5.The control board 8 is therefore a substrate having a relatively large area and is preferably sufficiently fixed to suppress distortion (strain), vibration, etc.

[0052] The base case 1B (inverter case), which houses the DC bus card 5, the power modules 3, and the first terminal block 7 (fixing component), accordingly has a bracket 19 that supports and fixes the control card 8 in the central region of the control card 8. The DC bus card 5, which is to be arranged on the central region of the control card 8 in the assembled state of the inverter box 1A, when viewed in a direction perpendicular to the card surface, has a support through-hole 59 through which the bracket 10 extends. The support through-hole 59 is provided between the phases of the capacitor components arranged to correspond to the power modules 3 arranged in a row along an end surface 5L of the DC bus card 5, and which form the n-phase branches 10L (10U, 10V, 10V). In the Fig. 1, Fig. 5, etc., the support through-hole 59 is formed at two positions located between the phases of the capacitor components 4, which are arranged and distributed at three positions to correspond to the three power modules 3 of the inverter circuit 10 that converts electric power between three-phase AC power and DC power. The two brackets 19 provided in the base case 1B are formed to correspond to the support through-holes 59 formed at the two positions.

[0053] It is effective to provide the two supports 19 in this manner for the inverter circuit 10 that converts electric power between three-phase AC power and DC power. In the case where the inverter circuit 10 is a circuit that converts electric power between, for example, n-phase AC power and DC power, where n represents a natural number, it is preferable to form (n-1) supports 19 in the base case 1B. In this case, it is preferable that the DC bus board 5 has the support through-holes 59 at (n-1) positions respectively located between the phases of the capacitor components 4 arranged and distributed to correspond to the power modules 3 arranged in a row along one end surface 5L of the DC bus board 5 and constituting the n-phase branches 10L.The provision of the support through holes 59 in the DC bus card 5 eliminates the need to provide a separate fixing support structure for the control card 8, and can reduce the size of the inverter box 1A.

[0054] As described above, the DC electrode terminal pairs 3T are provided to protrude from the ends 35 on one side of the power modules 3. The AC electrode terminals 3C corresponding to the branches 10L (10U, 10V, 10W) ​​are provided to protrude from the ends 33 located on the opposite side to the ends 35 on one side (see Fig. 1 and Fig. 5). Each second terminal block 92 has three fastening areas for fastening all three-phase AC electrode terminals 3. Each third terminal block 93 has three-phase AC relay terminals 9C connected to all three-phase AC electrode terminals 3C. The AC electrode terminals 3C of the power modules 3 are fastened to the AC relay terminals 9C of the third terminal block 93 and the second terminal block 92 by common fastening components 9. Each second terminal block 92 is fastened and fixed to the threaded holes 17c formed in the base case 1B by the fastening components 9, and each third terminal block 93 is fastened and fixed to the threaded holes 17d formed in the base case 1B by the fastening components 9.

[0055] As in Fig. As shown in Figure 1, each third terminal block 93 contains three AC output terminals 9T, which correspond to the three-phase AC relay terminals 9C. The AC relay terminal 9C and the AC output terminal 9T of each phase are connected by the busbar extending through the third terminal block 93. Each third terminal block 93 is provided with the current sensor 12, which detects a current in the busbars without contact, as described above. As shown in Fig. As shown in Figure 2, the AC output terminals 9T are located outside the inverter box 1A, even in the state where the cover case 1C is attached to the base case 1B. This allows the AC output terminals 9T to be sufficiently connected to the stator coils of each phase of each rotating electrical machine MG.

[0056] After the first terminal block 7, the second terminal blocks 92, the power modules 3, the DC bus card 5, and the third terminal blocks 93 are fixed to the base case 1B, the control card 8 is fixed to the base case 1B by the fixing members 9 in such a way as to cover these components. At this time, as described above, the signal transmission pins 31 of the power modules 3 extend through the signal transmission through-holes 81 of the control card 8. The signal transmission pins 31 are soldered to the signal transmission through-holes 81. Once all the components, including cables connecting the third terminal blocks 93 to the control card 8, etc., are attached to the base case 1B, the cover case 1C is fixed to the base case 1B by the fixing members 99 (9), thereby forming the inverter box 1A. [Other embodiments]

[0057] Other embodiments of the present invention will be described below. The structure of each embodiment described below can not only be used alone, but can also be combined with any of the configurations of the other embodiments, as long as no contradictions occur. (1) The above embodiment has been described with respect to the form in which the two inverter circuits 10 (10A, 10B) are provided to control the two rotating electrical machines MG. However, the inverter box 1A (inverter device 1) may include a single inverter circuit 10 or may include three or more inverter circuits 10. Any number of inverter circuits 10 may be provided as long as the DC bus card 5 and the power modules 3 can be fixed to the first terminal block 7 by fixing the positive connection terminals 55P of the DC bus card 5 and the positive terminals 3P of the power modules 3 to the first terminal block 7 (fixing member) by the common fixing members 9, and by fixing the negative connection terminals 55N of the DC bus card 5 and the negative terminals 3N of the power modules 3 to the first terminal block 7 by the common fixing members 9.(2) In the case where the DC bus card 5 and the power modules 3 are connected such that the power modules 3 face the end surface 5L of the DC bus card 5, it is preferable that the positive terminal 3P and the negative terminal 3N of each power module 3 be provided as a DC electrode terminal pair 3T protruding from the end 35 on one side of the power module 3, as described above. However, the manner in which the DC bus card 5 and the power modules 3 are connected is not limited to this form. For example, the DC bus card 5 and the power modules 3 may be connected such that the DC bus card 5 and the main body of each power module 3 overlap (partially or completely overlap) as viewed in the direction perpendicular to the card surface of the DC bus card 5. In this case, the positive terminal 3P and the negative terminal 3N need not be provided as a pair in the same part of the power module 3. (3) In the case where the inverter box 1A (inverter device 1) has a single inverter circuit 10, the power modules 3 can be placed only on one side of the DC bus card 5. Specifically, the inverter box 1A can be formed by either the power modules 3 constituting the first inverter circuit 10A or the power modules 3 constituting the second inverter circuit 10B in Fig. 1. In this case, the power modules 3 are not placed on both sides of the smoothing capacitor 40, but on one side of the smoothing capacitor 40, when viewed in the direction perpendicular to the board surface of the DC bus board 5. Therefore, in the case where the inverter box 1A has a single inverter circuit 10, the power modules 3 can be arranged or placed on one side.

[0058] However, even if the inverter box 1A includes a single inverter circuit 10, the power modules 3 may be placed on both sides of the smoothing capacitor 40 when viewed in the direction perpendicular to the board surface of the DC bus board 5. For example, the power modules 3 may be placed on both sides of the smoothing capacitor 40 by placing one of the three-phase power modules 3 of the inverter circuit 10, which converts electric power between three-phase AC power and DC power, on one side of the smoothing capacitor 40, and by placing the remaining two power modules 3 on the other side of the smoothing capacitor 40.

[0059] (4) The above description, which refers to the Fig. 1, Fig. 4, Fig. 5, Fig. 7, Fig.8, etc., is given with respect to the example in which a plurality of power modules 3 provided corresponding to the branches 10L (10U, 10V, 10W) ​​corresponding to a plurality of phases of the alternating current are arranged in a row along one end surface 5L of the DC bus board 5. In this example, the smoothing capacitor 40 is formed by connecting a plurality of capacitor components 4 in parallel, the number of capacitor components 4 corresponds to the number of power modules 3, and the capacitor components 4 are arranged to have a positional relationship corresponding to that of the power modules 3. It should be understood that in the case where the power modules 3 corresponding to the phases are not aligned in this manner, the capacitor components 4 may be arranged and distributed regardless of the arrangement of the power modules 3.Even if the power modules 3 corresponding to the phases are arranged or aligned in the manner described above, the capacitor components 4 can be arranged and distributed independently of the arrangement of the power modules 3.

[0060] (5) The above description is made using the example in which the smoothing capacitor 40 is formed by connecting a plurality of capacitor elements 4 in parallel. However, it should be understood that the smoothing capacitor 40 may be formed by a single element. In the above description, electrolytic capacitors are exemplified as the capacitor elements 4. However, elements having other structures, such as film capacitors, may be used as the capacitor element 4. INDUSTRIAL APPLICABILITY

[0061] The present invention can be applied to inverter devices that include a power module having a switching device and a smoothing capacitor, and that convert electric power between DC power and AC power. [Description of reference symbols] 1 inverter device 1A inverter box (inverter device) 1B Base housing (inverter housing) 1C Cover housing (inverter housing) 3 Power module 3N negative terminal 3P positive terminal 4 Capacitor component 5 DC bus card 5C Connection surface 5H conductive through-hole 5N negative electrode pattern 5P positive electrode pattern 7 first connection block (fixing component) 8 Control card 9 Fastening component 10 Inverter circuit 10A first inverter circuit (inverter circuit) 10B second inverter circuit (inverter circuit) 10L branch 11 Battery (DC power supply) 19 carriers 33 End on one side of the power module 40 smoothing capacitor 50 substrate 51 first map area 51E first electrode pattern 52 second map area 52E second electrode pattern 53 Insulation layer 55N negative connection terminal 55P positive connection terminal 57 Fastening component through hole 59 Support through hole E conductive material N negative electrode P positive electrode

Claims

[1] An inverter device (1) comprising: two inverter circuits that convert electric power between an n-phase AC power and a DC power, where n is a natural number; a power module (3) having a positive terminal (3P) connected to a positive electrode of a DC power supply (11) and a negative terminal (3N) connected to a negative electrode of the DC power supply (11), and forming at least one branch formed by serially connecting at least one switching component connected to the positive terminal and at least one switching component connected to the negative terminal; and a smoothing capacitor (40) connected between the positive electrode of the DC power supply (11) and the negative electrode of the DC power supply (11), comprising: an inverter housing (1B, 1C) accommodating the inverter circuits; a plate-like DC bus card (5) having a positive electrode pattern (5P) connected to the positive electrode of the DC power supply (11), a negative electrode pattern (5N) connected to the negative electrode of the DC power supply (11), and in which a positive-side terminal of the smoothing capacitor (40) is electrically connected to the positive electrode pattern (5P), a negative-side terminal of the smoothing capacitor (40) is electrically connected to the negative electrode pattern (5N), and to which the smoothing capacitor (40) is fixed; and a fixing member (7) which is a member independent of the inverter case (1B, 1C) and fixed to the inverter case (1B, 1C) and which maintains a relative positional relationship between the DC bus card (5) and a plurality of power modules (3) provided corresponding to a plurality of branches corresponding to a plurality of phases of an alternating current, wherein the positive terminal (3P) and the negative terminal (3N) of the power module (3) are provided as a DC electrode terminal pair protruding from one end on one side of the power module (3), the plurality of power modules (3) provided corresponding to the plurality of branches corresponding to the plurality of phases of the inverter current are arranged in a row along an end surface of the DC bus card (5), the two inverter circuits are formed by arranging power modules (3) on both sides of the DC bus card (5), which form each inverter circuit, when viewed in the direction perpendicular to the card surface of the DC bus card (5), the DC bus card (5) has a plurality of positive connection terminals (55P) which are electrically connected to the positive electrode pattern (5P) and which are respectively electrically connected to the positive terminals (3P) of the plurality of power modules (3), and a plurality of negative connection terminals (55N) which are electrically connected to the negative electrode pattern (5N) and which are respectively electrically connected to the negative terminals (3N) of the plurality of power modules (3), and the positive connection terminal (55P) and the positive terminal (3P), which correspond to each other, are fixed to the fixing member (7) by a common fixing member (9, 97), and the negative connection terminal (55N) and the negative terminal (3N), which correspond to each other, are fixed to the fixing member (7) by a common fixing member, so that the DC bus card (5) and the power modules (3) are fixed by the fixing member (7). [2] Inverter device according to claim 1, wherein the DC bus card (5) has a DC electrode pattern connection terminal pair electrically connected to the positive electrode pattern (5P) and the negative electrode pattern (5N), the fixing member (7) has a DC power supply connection terminal pair connected to the positive electrode (3P) and the negative electrode (3N) of the DC power supply (11), and a DC bus card connection terminal pair electrically connected to the DC power supply connection terminal pair, and the DC electrode pattern connection terminal pair of the DC bus card (5) is fixed to the DC bus card connection terminal pair by a fixing member. [3] Inverter device according to claim 1 or 2, wherein the first electrode pattern (51E), as one of the positive electrode pattern (5P) and the negative electrode pattern (5N), is formed on a first card surface (51) of the DC bus card (5) as a surface of an insulating layer (53) forming a substrate (50), and a second electrode pattern, as the other of the positive electrode pattern (5P) and the negative electrode pattern (5N), is formed on a second card surface of the DC bus card (5), as the other surface of the insulating layer (53), each terminal of the DC bus card (5) is fixed by the fixing component (9, 97) such that the first card surface (51) contacts terminals provided on other components, the terminal electrically connected to the second electrode pattern (52E) has a connection pad formed on the first card surface (51) such that it is separated from the first electrode pattern (51E), and a conductive through-hole extending through the insulation layer (53) and formed separately from a fixing member through-hole through which the fixing member extends, and the conductive through-hole has a conductive material (E) on its inner wall, and the second electrode pattern (52E) is electrically connected to the connection pad through the conductive material (E). [4] The inverter device according to any one of claims 1 to 3, wherein the power modules (3) are arranged on both sides of the smoothing capacitor (40) as viewed in a direction perpendicular to a card surface of the DC bus card (5). [5] The inverter device according to any one of claims 1 to 4, wherein the smoothing capacitor (40) is formed by connecting a plurality of capacitor components in parallel, the number of the capacitor components corresponds to that of the power modules, and the capacitor components are arranged such that a position of the capacitor components corresponds to that of the power modules (3). [6] Inverter device according to one of claims 1 to 5, wherein the smoothing capacitor (40) is formed by parallel connection of the plurality of capacitor components, the number of capacitor components corresponds to that of the power modules (3), and the capacitor components are arranged such that a position of the capacitor components corresponds to that of the power modules (3), wherein the inverter device further comprises: a control card (8) positioned to cover the power modules (3) and the DC bus card (5) when viewed in a direction perpendicular to the card surface of the DC bus card (5), and which controls the two inverter circuits; and the inverter housing (1B, 1C) which accommodates the DC bus card (5), the power modules (3) and the fixing component (3), and which has at least (n-1) supports (19) which support and fix the control card in a central area of ​​the control card (8), wherein the DC bus card (5) has support through-holes (59) through which the supports (19) extend, and each support through-hole (59) is provided between the phases of the capacitor components arranged to correspond to the power modules (3) arranged in a row along an end face of the DC bus card (5) and forming the n-phase branches.

Images