JP5926651B2 - DC-DC converter device and power converter device - Google Patents

Description

  The present invention relates to a DC-DC converter device and a power conversion device that can be miniaturized even at high output and have excellent vibration resistance or shock resistance.

  An electric vehicle and a plug-in hybrid vehicle include an inverter device for driving a motor with a high-voltage storage battery for driving power and a low-voltage storage battery for operating auxiliary equipment such as a vehicle light and a radio. Such a vehicle is equipped with a DC-DC converter device that performs power conversion from a high voltage storage battery to a low voltage storage battery or power conversion from a low voltage storage battery to a high voltage storage battery.

  The DC-DC converter device includes a high-voltage side switching circuit that converts a high-voltage direct current into an alternating current, a transformer that converts the alternating high voltage into an alternating low voltage, and a low-voltage switching circuit that converts the low-voltage alternating voltage into a direct current. It has.

  As a conventional DC-DC converter device, a structure in which electronic components constituting a transformer, a high-voltage side switching circuit and a low-voltage side switching circuit are mounted on a wiring board, and the wiring board is fixed to a cooling block having heat radiation fins Is known (see, for example, Patent Document 1).

JP 2005-143215 A

  In Patent Document 1, all electronic components constituting the DC-DC converter device are arranged on one wiring board. For this reason, if a component such as a transformer having a large volume or weight is used in order to obtain a large output, vibration resistance or impact resistance is lowered.

A DC-DC converter device according to the present invention includes a transformer, a high-voltage side switching circuit unit connected to the primary side of the transformer, a low-voltage circuit board unit connected to the secondary side of the transformer, and at least one choke coil Including a transformer, a high voltage side switching circuit unit, and a case member that houses the low voltage side switching circuit unit . The case member extends along the bottom surface and the outer periphery of the bottom surface unit. And at least a transformer is arranged so that at least one side faces directly along one side of the outer peripheral side wall of the case member, and the bottom surface of the case member has a rectangular shape. on the center of the area, characterized in that the low-voltage circuit board portion is disposed.

  According to the present invention, the low-voltage circuit board portion is formed on the center of the case member, or no component is arranged, and the transformer arranged along the outer peripheral side wall of the case member is separated by the outer peripheral side wall. Since it is supported, vibration resistance or impact resistance can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS The external appearance perspective view which shows one Embodiment of a power converter device provided with the DC-DC converter apparatus and inverter apparatus of this invention. The external appearance perspective view which looked at the DC-DC converter apparatus illustrated in FIG. 1 from the bottom face side. The figure which shows one Embodiment of the circuit structure of the DC-DC converter apparatus shown in figure by FIG. FIG. 2 is a schematic plan view of the DC-DC converter device illustrated in FIG. 1. The perspective view which shows the mounting state of the DC-DC converter apparatus illustrated by FIG. The disassembled perspective view which shows one Embodiment of the high voltage side switching circuit part. The disassembled perspective view which shows one Embodiment of a low-voltage circuit board part. FIG. 6 is a plan view showing a modification of the first embodiment. The figure which shows Embodiment 2 of the circuit structure of the DC-DC converter apparatus of this invention. FIG. 4 is a schematic plan view of a DC-DC converter device according to a second embodiment.

Embodiment 1
[Power converter]
Hereinafter, an embodiment of a DC-DC converter device and a power converter of the present invention will be described with reference to the drawings.
FIG. 1 is an external perspective view of a power conversion device including the DC-DC converter device of the present invention, and FIG. 2 is an external perspective view of the DC-DC converter device shown in FIG.
The power conversion device 1 is obtained by integrating the DC-DC converter device 100 and the inverter device 200. FIG. 1 shows the DC-DC converter device 100 and the inverter device 200 in a separated state. The DC-DC converter device 100 is fixed to the upper surface side of the case of the inverter device 200 with a plurality of bolts.

  The power conversion device 1 is applied to a vehicle such as an electric vehicle or a plug-in hybrid vehicle, and the inverter device 200 drives a traveling motor with electric power from an on-vehicle high voltage storage battery. The vehicle is equipped with a low voltage storage battery for operating an auxiliary machine such as a light or a radio, and the DC-DC converter device 100 performs power conversion from a high voltage storage battery to a low voltage storage battery or a high voltage from a low voltage storage battery. Perform power conversion to storage battery.

  A cooling channel 204 through which a cooling medium flows is formed in the case 201 of the inverter device 200 in order to cool the heat generating components in the inverter device 200. The cooling medium flows into the cooling channel from the inlet pipe 202 and flows out from the outlet pipe 203. The cooling channel is formed in a U shape so as to connect the inlet pipe 202 and the outlet pipe 203 along the outer peripheral side wall of the case 201 of the inverter device 200. On the other hand, the bottom member 102 of the case member 101 of the DC-DC converter device 100 is fixed so as to face the inverter device 200. The DC-DC converter device 100 functions as a lid that covers the upper opening of the cooling flow path 204 when the inverter device 200 is fixed. That is, the wall surface is the bottom surface portion 102 of the DC-DC converter device 100 and the upper surface side of the cooling flow path 204. As a result, the DC-DC converter device 100 is directly cooled by a cooling medium such as cooling water flowing through the cooling flow path 204. A seal (not shown) such as an O-ring is provided between the bottom surface portion 102 of the case member 101 of the DC-DC converter device 100 and the top surface portion of the inverter device 200 so that the cooling medium in the cooling flow path 204 does not leak. ) Is provided.

In the present embodiment, a mixture of antifreeze and water in a ratio of 1: 1 is generally suitable as the cooling medium. However, other cooling media can be used.
As shown in FIG. 2, the bottom surface portion 102 of the DC-DC converter device 100 is provided with a flow path wall 151 that projects into the cooling passage 204 of the inverter device 200 and divides the flow of the cooling medium. In addition, an opening 152 that forms a U-shaped cooling passage through which the cooling medium divided by the flow path wall 151 flows is formed in the bottom surface portion 102 of the DC-DC converter device 100.

  The cooling medium flowing into the cooling flow path 204 from the inlet pipe 202 of the inverter device 200 is divided by the flow path wall 151 of the DC-DC converter apparatus 100 and also flows into the opening 152 of the DC-DC converter apparatus 100. . The cooling medium that has flowed into the opening 152 of the DC-DC converter device 100 circulates in a U shape and returns to the cooling flow path 204 again. In the opening 152, the bottom surface portion 102 of the DC-DC converter device 100 serves as a lid member for the cooling flow path 204, and the DC-DC converter device 100 is effectively prevented by the cooling medium flowing in the opening 152. Can be cooled.

  In addition, the power converter device comprised by the said inverter apparatus 200 and the DC-DC converter apparatus 100 shows one Embodiment, The shape, structure, etc. of each apparatus can be applied with various modifications. It is. Further, the cooling device that cools the inverter device 200 and the DC-DC converter device 100 is shown as an embodiment, and in addition, a cooling device using a cooling gas such as air may be used. There is no.

[Circuit Configuration of DC-DC Converter Device]
Next, the DC-DC converter device 100 will be described. FIG. 3 is a diagram showing an embodiment of a circuit configuration of the DC-DC converter device 100.
As shown in FIG. 3, a DC-DC converter device 100 shown as an embodiment of the present invention is a bidirectional DC-DC converter. The DC-DC converter device 100 includes a high voltage side switching circuit unit 107, a low voltage side switching circuit unit 150, and a transformer (Tr) provided between the high voltage side switching circuit unit 107 and the low voltage side switching circuit unit 150. 103). Switching control of the high voltage side switching circuit unit 107 and the low voltage side switching circuit unit 150 is performed by the control circuit unit CTR.

  The high voltage side switching circuit unit 107 is connected to MOSFETs (switching elements) H1 to H4, a choke coil Lr, a smoothing capacitor Cn, an IGBT switch H0, and an IGBT switch H0 connected as an H bridge type switching circuit. A shunt resistor Ri and a choke coil Lc are provided. The smoothing capacitor element Cn is disposed on the input side of the H-bridge type switching circuit, and smoothes the input current input to the high voltage side switching circuit unit 107. A gate resistor (not shown) is connected to the gate terminals of the switching elements H1 to H4.

  The control circuit unit CTR can measure a potential difference between both ends of the shunt resistor Ri and detect a high-voltage current. The choke coil Lc is disposed between the high voltage power supply HV (−) and the shunt resistor Ri and functions as a normal mode filter.

  The high-voltage circuit board 40 surrounded by a broken line in FIG. 3 is provided with wiring that connects the switching elements H1 to H4 constituting the high-voltage side switching circuit unit 107 in an H-bridge connection. The high voltage circuit board 40 also includes power semiconductor modules 35 to be described later which are switching elements H1 to H4, a power semiconductor module 36 which is an IGBT switch H0, a smoothing capacitor 38 (Cn), and other electronic components other than the resonance coil Lr. Are mounted, and their wiring patterns are also provided. The high voltage side switching circuit unit 107 will be described later with reference to FIG.

  The low voltage side switching circuit unit 150 includes MOSFETs (switching elements) S3 and S4 that constitute a synchronous rectifier circuit and MOSFETs (switching elements) S1 that constitute an active clamp circuit in order to ensure high output on the low voltage side. , S2, reactors L1 and L2 configured as a full-wave rectification type double current (current doubler), an output capacitor Co, a noise filter inductor Lf, and a capacitor Cf. The gate resistances of the MOSFETs S1 to S4 are not shown.

  In the low voltage circuit board portion 108 surrounded by a broken line in FIG. 3, wirings for connecting the switching elements S1 to S4 constituting the low voltage side switching circuit portion 150 are provided. On the low-voltage circuit board portion 108, electronic components other than the reactors L1 and L2 among the electronic components shown in FIG. 3 are mounted and their wiring patterns are also provided. The low voltage circuit board unit 108 will be described later with reference to FIG.

  High output is achieved by arranging the small-sized reactors (L1, L2) of the switching circuit and the smoothing reactor in parallel so as to have symmetry. As described above, by arranging the small reactors in two circuits, it is possible to reduce the size of the entire DC-DC converter device as compared with the case where one large reactor is disposed. In addition, an active clamp circuit using MOSFETs S1 and S2 having freewheeling diodes is provided to suppress the occurrence of surge voltage during switching and reduce the breakdown voltage of the switching element, thereby reducing the breakdown voltage of circuit components. The device is downsized.

[Structure of DC-DC converter device]
4 is a schematic plan view of the DC-DC converter device shown in FIG. 1, and FIG. 5 is a perspective view showing a mounted state of the DC-DC converter device shown in FIG.
Case member 101 of DC-DC converter device 100 is formed of a conductive metal such as an aluminum-based metal. The bottom surface portion 102 of the case member 101 has a substantially rectangular shape in a plan view, and an outer peripheral side wall 115 raised substantially perpendicular to the bottom surface portion 102 is integrally formed on the outer periphery of the bottom surface portion 102. .
In the case member 101, a plurality of storage chambers are provided by partition walls 111a to 111f described later. These accommodating chambers are provided with a transformer 103, choke coils 104 and 105, a noise filter coil 106, a power semiconductor module 35 constituting a switching element H1 to H4, a smoothing capacitor 38, and the like, and a high voltage side switching circuit section. 107, a low-voltage circuit board portion 108 provided with switching elements S1 to S4 and the like are accommodated. The arrangement of these electronic components will be described later.

  3, the transformer 103 corresponds to the transformer Tr, the choke coils 104 and 105 correspond to the reactors L1 and L2 of the current doubler, and the noise filter coil 106 corresponds to the noise filter inductor Lf. Yes.

―Placement of electronic components in case material―
The arrangement of electronic components in the case member will be described with reference to FIGS. In the following description, “up, down, left, and right” are used to indicate the positional relationship within the plane of FIG. 4 and FIG.
Peripheral side wall 115 of the case member 101 has a first long side 115a of the lower side of FIG. 4 and 5, a second long side 115 c of the upper side of FIG. 4 and 5, the first on the left side of FIG. 4 and 5 the short side 115 b of, and a second short side 115d of the right side of FIG. 4 and 5.

  In the case member 101 surrounded by the outer peripheral side wall 115, the first partition wall 111a installed in parallel with the lower first long side 115a and the upper second long side 115b are installed in parallel. The second partition wall 111b, the third partition wall 111c installed in parallel with the second short side 115d on the right side, and the first long side 115a on the lower side and orthogonal to the long side 115a The fourth to sixth three partition walls 111d, 111e, 111f installed at predetermined intervals along the line are installed.

The first storage chamber in which the low-voltage circuit board unit 108 is stored is partitioned by the first partition wall 111a, the second partition wall 111b, the third partition wall 111c, and the first short side 115c on the left side. Has been.
The second storage chamber in which the high-voltage side switching circuit unit 107 is stored is partitioned by the third partition wall 111c, the second short side 115d on the right side, and the first and second long sides 115a and 115b. .
The third storage chamber in which the choke coil 104 is stored is partitioned by the first partition wall 111a, the fourth partition wall 111d, the fifth partition wall 111e, and the first long side 115a.
These partition walls constitute a storage chamber together with the outer peripheral wall 115 of the case member 101 as a partition wall member.
The fourth storage chamber in which the transformer 103 is stored is partitioned by the first partition wall 111a, the fifth partition wall 111e, the sixth partition wall 111f, and the first long side 115a.
These partition walls constitute a storage chamber together with the outer peripheral wall 115 of the case member 101 as a partition wall member.
The fifth storage chamber in which the choke coil 105 is stored is partitioned by the first partition wall 111a, the sixth partition wall 111f, the third partition wall 111c, and the first long side 115a.
These partition walls constitute a storage chamber together with the outer peripheral wall 115 of the case member 101 as a partition wall member.
The sixth storage chamber in which the noise filter coil 106 is stored is partitioned by the second partition wall 111b, the upper second long side 115b, and the left first short side 115c.

  The third to fifth accommodation chambers are juxtaposed from left to right along the long side 115a. That is, the transformer 103 is disposed in the fourth storage chamber so that one side surface thereof directly faces one long side 115 a of the outer peripheral side wall 115. In the third and fifth storage chambers adjacent to the transformer 103, the choke coils 104 and 105 are respectively arranged so that one side faces the long side 115a of the outer peripheral side wall 115 directly. That is, the transformer 103 and the choke coils 104 and 105 are constrained by the surrounding wall members.

  The first storage chamber is arranged above the third to fifth storage chambers, that is, inside the case member 101 relative to the transformer 103 and the choke coils 104 and 105. The low voltage circuit board portion 108 accommodated in the first accommodating chamber has one side surface on the short side directly facing the short side 115c on the left side of the outer peripheral side wall 115, and the longitudinal direction thereof is the first and first side. The two partition walls 111a and 111b are arranged in parallel. That is, the low voltage circuit board portion 108 is restrained by the surrounding wall member.

  The low voltage circuit board portion 108 is arranged so that a part thereof is located on the center C of the rectangular region of the bottom surface portion 102 of the case member 101. That is, in FIG. 4, the straight line indicated by two two-dot chain lines is a diagonal line of the bottom surface part 102 having a rectangular shape, and the low voltage circuit board part 108 is placed on the center C indicated by a double circle at the intersection of the diagonal lines. Is installed.

  As described above, the low-voltage circuit board unit 108 is mounted with the active clamp circuit and the switching elements S1 to S4 of the synchronous rectifier circuit, the output capacitor Co, and the like surrounded by a dotted line in FIG. Is provided.

  The sixth storage chamber is disposed between the low-voltage circuit board portion 108 and the other long side 115c of the outer peripheral side wall 115, that is, between the second partition wall 111b and the long side 115b. The noise filter coil 106 accommodated in the sixth accommodating chamber is disposed so that one side surface thereof directly faces the other long side 115 b of the outer peripheral side wall 115.

  The second storage chamber is provided between the third partition wall 111c and the right short side 115d. The high-voltage side switching circuit unit 107 housed in the second housing chamber is arranged such that one side surface of the long side faces the short side 115d on the right side of the outer peripheral side wall 115 directly. The other side surface on the long side of the high voltage side switching circuit unit 107 is arranged to face the other side surface on the short side of the low voltage circuit board unit 108 and one side surface of the choke coil 105, that is, the third partition wall 111c. ing. In other words, the voltage-side switching circuit unit 107 is constrained by the surrounding wall members and is arranged in a direction substantially perpendicular to the longitudinal direction of the low-voltage circuit board unit 108.

  The high-voltage side switching circuit unit 107 includes a high-voltage circuit board 40 on which wirings for connecting the switching elements H1 to H4 and the switching elements H1 to H4 to the bridge circuit are formed, as will be described later. The high voltage circuit board 40 is mounted with a choke coil Lc and a shunt resistor Ri. That is, on the high voltage circuit board 40, electronic components other than the switching elements H1 to H4 are mounted among the electronic components in the region surrounded by the dotted line in FIG.

  Between the long side 115b of the outer peripheral side wall 115 and the low-voltage circuit board portion 108, an opening 109 for high-voltage power supply and an opening 110 for low-voltage power output are provided on both sides of the noise filter coil 106, respectively. Is formed.

-High voltage side switching circuit 107-
FIG. 6 is an exploded perspective view showing an embodiment of the high voltage side switching circuit unit 107.
The high voltage side switching circuit unit 107 configured as a high voltage module includes a high voltage circuit board 40, power semiconductor modules 35 and 36, a metal base 30, a leaf spring 33, a temperature sensor 34, and a smoothing capacitor element 38. . The power semiconductor module 35 corresponds to the MOSFETs H1 to H4 in FIG. 3, and the power semiconductor module 36 corresponds to the IGBT switch H0 in FIG. Further, the smoothing capacitor element 38 corresponds to the smoothing capacitor Cn of FIG.
The choke coil Lr can be integrated into the high voltage module shown in FIG. 6 or can be installed separately.

  The metal base 30 is formed by, for example, aluminum die casting or the like, and is fixed to the inner surface of the bottom surface portion 102 of the case member 101 by a fastening member such as a screw. The metal base 30 has a recess 30a formed in the upper part, and power semiconductor modules 35 and 36 are disposed in the recess 30a. The power semiconductor modules 35 and 36 are pressed against each other by a leaf spring 33 disposed above the power semiconductor modules 35 and 36, and are in contact with the bottom surface of the concave portion of the metal base 30 through an insulating sheet 31 having good thermal conductivity. The leaf spring 33 is fixed to the inner surface of the bottom surface portion 102 of the case member 101 by a fastening member such as a screw.

  By using a material having high thermal conductivity such as A6063 as the metal base 30, for example, a general aluminum die casting material such as ADC12 type can be used for the case member 101. Thereby, compared with the case where the metal base 30 is not attached and the entire case member 101 is formed of a material having high thermal conductivity, the material cost can be reduced.

  Thermally conductive grease (not shown) between the inner surface of the bottom surface portion 102 of the case member 101 and the metal base 30, between the metal base 30 and the insulating sheet 31, and between the insulating sheet 31 and the power semiconductor modules 35 and 36. Is applied. As described above, the bottom surface portion 102 of the case member 101 constitutes the cooling flow path 204 together with the inverter device 200, and the heat generated from the heat generating members such as the power semiconductor modules 35 and 36 circulates in the cooling flow path 204. Cooled by the cooling medium.

  The smoothing capacitor 38 is accommodated in a capacitor case (not shown) fixed to the metal base 30. This capacitor case is disposed above the leaf spring 33 that press-contacts the power semiconductor modules 35 and 35 with a slight gap from the leaf spring 33.

  The temperature sensor 34 is fixed to the metal base 30 by a fastening member such as a screw. The temperature sensor 34 is connected to the control circuit unit CTR illustrated in FIG. 3 by a harness. The temperature sensor 34 detects the temperature of the power semiconductor modules 35 and 36 via the metal base 30 and transmits the detection signal to the control circuit unit CTR. The control circuit unit CTR determines whether or not an abnormality has occurred based on the temperature information transmitted from the temperature sensor 34. If it is determined that there is an abnormality, the output from the DC-DC converter device 100 is limited. Perform protection control.

  The high voltage circuit board 40 is mounted so as to rise substantially perpendicular to the bottom surface portion 102 of the case member 101. The lower end surface of the high-voltage circuit board 40 is located in the vicinity of the inner surface of the bottom surface portion 102 of the case member 101 and covers the sides of the power semiconductor modules 35 and 36 attached to the metal base 30. By doing so, the width (height) of the high voltage circuit board 40 is widened, the area of the high voltage circuit board 40 is increased, and the internal space of the case member 101 is effectively utilized.

Lead terminals of the power semiconductor modules 35 and 36 are connected to the high voltage circuit board 40. The lead terminals of the power semiconductor modules 35 and 36 are inserted into terminal holes provided in the high voltage circuit board 40 and soldered.
The switching elements H1 to H4 of the four power semiconductor modules 35 connected to the high voltage circuit board 40 are connected as an H bridge circuit by wiring provided on the high voltage circuit board 40.
A connector 41 having a plurality of connector pins on the upper side is mounted on the high voltage circuit board 40. Although not shown, a control circuit board on which the control circuit unit CTR shown in FIG. 3 is formed is arranged on the upper side of the case member 101. Each connector pin of the connector 41 is provided on the control circuit board. The pin hole is inserted and soldered. The control circuit unit CTR and the power semiconductor modules 35 and 36 are electrically connected by a connector 41, and the control circuit unit CTR performs switching control of the power semiconductor module 35 and on / off control of the power semiconductor module 36.

  A choke coil 42 (Lc in FIG. 3) is mounted on the high voltage circuit board 40. The choke coil 42 is electrically connected between the (+) or (−) of the high voltage power supply and the H bridge circuit, and functions as a normal mode filter.

Although not shown, the two smoothing capacitor elements 38 are connected in parallel by a connecting bus bar and connected to the high voltage circuit board 40.
In the above-described embodiment, the high voltage circuit board 40 is exemplified as a structure in which the high voltage circuit board 40 is raised and fixed substantially perpendicularly to the inner surface of the bottom surface portion 102 of the case member 101. However, the high voltage circuit board 40 may be arranged on the upper side of the power semiconductor modules 35 and 36 and / or the smoothing capacitor element 38 in parallel with the inner surface of the bottom surface portion 102 of the case member 101.
Further, the power semiconductor modules 35 and 36 may be directly brought into contact with the inner surface of the bottom surface portion 102 of the case member 101 without using the metal base 30.

-Low voltage circuit board 108-
FIG. 7 is an exploded perspective view of the low-voltage circuit board unit 108.
The low-voltage circuit board portion 108 includes a base substrate 50 formed of an aluminum-based metal having good thermal conductivity. Although not shown, an insulating film is formed on one surface of the base substrate 50, and wirings constituting the active clamp circuit and the synchronous rectifier circuit shown in FIG. 3 are formed on the insulating film. As described above, the low-voltage circuit board portion 108 includes the power semiconductor module 51 (corresponding to the switching elements S1 to S4), the output capacitor 52 (Co in FIG. 3), and the active clamp circuit capacitor 53 (Cc in FIG. 3). It is mounted with solder. The power semiconductor module 51 is a surface mount MOSFET package, the bottom surface of which is made of metal such as copper, and has the same potential as the drain electrode of the MOSFET chip inside the module. A good heat dissipation structure that also serves as an electrical connection can be formed by connecting the wiring with the solder.

  Referring to FIG. 5, the transformer 103 and the choke coils 104 and 105 are connected to the low voltage circuit board unit 108 by bus bars 121, 122, and 123, respectively. The noise filter coil 106 is connected to the low voltage circuit board 108 by a bus bar 124. Although not shown, the high-voltage side switching circuit unit 107 is connected to the transformer 103 by a bus bar.

As described above, the transformer 103, the choke coils 104 and 105, the noise filter coil 106, the high voltage side switching circuit unit 107, and the low voltage circuit board unit 108 are arranged in the case member 101 of the DC-DC converter device 100. Has been accommodated.
That is, as shown in FIG. 4, the low voltage circuit board portion 108 is disposed on the center C of the rectangular region of the bottom surface portion 102 of the case member 101. As described above, the transformer 103 and the choke coils 104 and 105 are located along the one long side 115a of the outer peripheral side wall 115 of the case member 101 at a position deviated from the center C of the rectangular region of the bottom surface portion 102 of the case member 101. Directly facing each other. Further, the high voltage side switching circuit portion 107 is directly opposed along the other short side 115d of the outer peripheral side wall 115 of the case member 101 at a position deviated from the center C of the rectangular region of the bottom surface portion 102 of the case member 101. Are arranged.

  The low voltage circuit board unit 108 has a weight of about 200 to 300 g, for example. On the other hand, the weight of the transformer 103 is about 250 to 350 g, for example, and the weights of the choke coils 104 and 105 are about 150 to 250 g, respectively. As shown in FIG. 4, the rectangular area of the low voltage circuit board portion 108 is about 4 to 5 times that of the transformer 103 and about 6 to 8 times that of the choke coils 104 and 105. Therefore, the weight per unit area of the transformer 103 is the largest, and the choke coils 104 and 105 are also larger than the low voltage circuit board portion 108, respectively. Since the high voltage side switching circuit unit 107 includes the smoothing capacitor 38, the weight is, for example, 250 g to 350 g, and the area is only slightly smaller than that of the low voltage side switching circuit unit 108 as illustrated in FIG. However, the weight per unit area is larger than that of the low-voltage circuit board unit 108.

  The height of the transformer 103 and the choke coils 104 and 105 is, for example, about 25 to 40 mm, and is larger than the thickness of the low voltage circuit board portion 108 (the height from the inner surface of the bottom surface portion 102 of the case member 101). The high voltage side switching circuit unit 107 is thicker than the low voltage circuit board unit 108 because the smoothing capacitor 38 is disposed above the power semiconductor modules 35 and 36.

As described above, in one embodiment of the present invention, a part having a large weight and height per unit area is disposed facing the outer peripheral side wall 115 of the case member 101, and the weight and thickness (height per unit area) are determined. The low-voltage circuit board portion 108 with a small) is arranged so that a part thereof is located on the center C of the rectangular region of the bottom surface portion 102 of the case member 101.
For this reason, it is excellent with respect to vibration resistance or impact resistance.

(Modification)
FIG. 8 is a plan view showing a modification of the first embodiment.
As described above, the transformer 103 and the choke coils 104 and 105 are disposed in the accommodating portion 131 formed by one long side 115a of the outer peripheral side wall 115 and the partition walls 111d, 111e, and 111f, respectively. As shown in FIG. 8, the modification is characterized in that a resin 141 is filled in each accommodating portion 131 formed by one long side 115 a of the outer peripheral side wall 115 and the partition walls 111 d to 111 f.

Each of the transformer 103 and the choke coils 104 and 105 disposed in each housing portion 131 is fixed with its outer peripheral side surface covered with a resin 141. For this reason, the transformer 103 and the choke coils 104 and 105 can be fixed more reliably, and vibration resistance or impact resistance can be improved.
The height of the partition walls 111a to 111f may be lower than the outer peripheral side wall 115, and may be about 1/3 or more of the height of each component.

  In the first embodiment described above, it has been described that the electronic components 103, 104, and 105 that are heavy and tall are arranged to face the long side 115 a of the outer peripheral side wall 115. Further, in the modification, it has been described that these electronic components 103 to 105 are fixed by sealing the periphery with resin. In the first embodiment or the modification, the electronic components 103 to 105 are fastened by fastening members and fixed to the bottom surface portion 102 of the base member 101.

Embodiment 2
FIG. 9 is a diagram showing a circuit configuration as a second embodiment of the DC-DC converter device of the present invention.
9 is different from FIG. 3 in that a center tap is provided on the secondary coil side of the transformer Tr, the reactor L1 is connected between the center tap and the positive electrode of the low-voltage power supply output unit, and the reactor L2 is removed. It is. Other than that, the configuration is the same as that shown in FIG.

FIG. 10 is a schematic plan view showing one embodiment of a mounted state of the circuit shown in FIG.
In the DC-DC converter device 100 shown in the second embodiment, only the choke coil 104 is required, and it is not necessary to mount the choke coil 105.
Therefore, in the DC-DC converter device 100 illustrated in FIG. 10, the noise filter coil 106 is disposed at the place where the choke coil 105 is disposed on the bottom surface portion 102 of the case member 101 in the first embodiment.

The high voltage side switching circuit unit 107 is moved to one long side 115a side of the outer peripheral side wall 115, and the positions of the opening 109 for high voltage power supply input and the opening 110 for low voltage power output are the high voltage side switching circuit unit. 107 and the other long side 115c of the outer peripheral side wall 115 are moved.
Then, the low-voltage circuit board portion 108 is moved closer to the position where the noise filter coil 106 was disposed, and is disposed close to the other long side 115 c of the outer peripheral side wall 115. That is, the low-voltage circuit board portion 108 has one side surface on the short side side along one short side 115b of the outer peripheral side wall 115 and one side surface on the long side side along the other long side 115c of the outer peripheral side wall 115. Directly facing each other.

By arranging in this way, as shown in FIG. 10, a mounting structure in which no components are mounted on the center C of the rectangular region of the bottom surface portion 102 of the case member 101 is obtained. That is, the low-voltage circuit board portion 108 can also be mounted at a position off the center C of the rectangular area of the bottom surface portion 102 of the case member 101.
The center of the rectangular region of the bottom surface portion 102 of the case member 101 has the smallest strength, but no parts are arranged in the vicinity of the center C, so that the vibration resistance or shock resistance of the DC-DC converter device 100 is improved. Can be further improved.

According to each embodiment of the present invention, the following effects can be obtained.
(1) An electronic component having a large weight and height per unit area, such as the transformer 103 and the choke coils 104 and 105, is arranged along one long side 115a of the outer peripheral side wall 115 of the case member 101 of the DC-DC converter device 100. The structure is arranged directly facing each other. Therefore, these parts can be supported and restrained by the outer peripheral side wall 115.

(2) The low voltage circuit board portion 108 having a small weight and thickness (height) per unit area is disposed on the center C of the rectangular region of the bottom surface portion 102 of the case member 101 (Embodiment 1), or A structure (Embodiment 2) in which none of the components are arranged is employed. For this reason, in combination with the above (1), it is possible to make the DC-DC converter device 100 excellent in vibration resistance or impact resistance.

(3) The partition walls 111a to 111f are integrally formed on the bottom surface portion 102 of the case member 101, and together with the outer peripheral side wall 115, the transformer 103, choke coils 104 and 105, the low voltage circuit board portion 108, and the high voltage side switching circuit. Each of the portions 107 is formed with a storage portion 131 that stores the portion 107. For this reason, the transformer 103, the choke coils 104 and 105, the low voltage circuit board portion 108, and the high voltage side switching circuit portion 107 are supported and restrained, and the vibration resistance or shock resistance of the DC-DC converter device 100 is increased. Can be improved.
(4) Resin 141 is filled in each accommodating portion 131 that accommodates the transformer 103 and the choke coils 104 and 105 to cover the outer peripheral side surfaces of the transformer 103 and the choke coils 104 and 105 to increase the fixing strength. For this reason, the vibration resistance or impact resistance of the DC-DC converter device 100 can be improved.

(5) The bus bars 121 to 124 are used to connect the transformer 103, the choke coils 104 and 105, the noise filter coil 106, and the low voltage circuit board unit 108, and the transformer 103 and the high voltage side switching circuit unit 107. Yes. For this reason, the low voltage circuit board unit 108 and the high voltage circuit board 40 can be formed separately from one control circuit board, and the area of the control circuit board is reduced, so that the DC-DC converter The vibration resistance or impact resistance of the apparatus 100 can be improved.

(6) The high voltage side switching circuit unit 107 employs a structure in which the power semiconductor modules 35 and 36 are pressed against the metal base 30. For this reason, by using a material having high thermal conductivity for the metal base 30, the case member 101 can be made of a normal inexpensive metal material, and the cost can be reduced.

(7) The power conversion device 1 is configured by fixing the bottom surface portion 102 of the DC-DC converter device 100 to the inverter device 200 in which the cooling flow path 204 through which the cooling medium flows is formed. Therefore, the DC-DC converter device 100 and the inverter device 200 can be efficiently cooled.
(8) A flow path wall 151 that divides the cooling flow path 204 of the inverter device 200 is provided on the bottom surface portion 102 of the DC-DC converter apparatus 100, and communicates from one surface of the flow path wall 151 to the other surface. A U-shaped opening 152 was provided. The cooling medium flows into the opening 152 through the flow path wall 151, flows through the opening 152, and returns to the cooling flow path 204. Since the DC-DC converter device 100 is directly cooled by the cooling medium while the cooling medium flows through the opening 152, the cooling efficiency of the DC-DC converter device 100 is excellent.

In addition, the transformer 103, the choke coils 104 and 105, the noise filter coil 106, the low-voltage circuit board portion 108, and the high-voltage side mounted on the inner surface of the bottom surface portion 102 of the case member 101 shown in the first and second embodiments. The arrangement of the switching circuit unit 107 is merely an example, and various modifications can be made.
For example, the transformer 103 may be disposed at the corner of the case member 101. The arrangement of the high voltage side switching circuit unit 107 may be replaced with the arrangement of the transformer 103 and the choke coils 104 and 105, and the high voltage side switching circuit unit 107 may be arranged almost in parallel with the low voltage circuit board unit 108.

A noise filter capacitor Cf may be mounted on the bottom surface portion 102 of the case member 101.
Further, a resonance capacitor element and a resonance coil constituting a resonance circuit may be connected in series to the primary side of the main transformer Tr, and zero voltage switching (ZVS) may be performed at a high switching frequency (100 kHz). Switching loss can be reduced and conversion efficiency can be improved. Further, a noise filter capacitor may be added to the input section of the high voltage side switching circuit section. A resonance capacitor and / or a noise filter capacitor may be mounted on the bottom surface portion 102 of the case member 101.

  The smoothing capacitor element 38 (Cn), the resonance capacitor Cc, and the noise filter capacitor Cy may be housed in one case to constitute a capacitor module. In this case, the capacitor module is a constituent member of the high voltage side switching circuit unit 107. The capacitor module is preferably disposed at a position directly facing along at least one side of the outer peripheral side wall 115 of the case member 101.

  In the said embodiment, it illustrated as the DC-DC converter apparatus 100 which is integrated with the inverter apparatus 200 and comprises the power converter device 1. FIG. However, the DC-DC converter device 100 of the present invention can be integrated into a device other than the inverter device 200, or can be mounted alone at a predetermined mounting position. Moreover, in the said embodiment, although the power converter device 1 mounted in vehicles, such as an electric vehicle and a plug-in hybrid vehicle, was demonstrated to the example, this invention is not limited to these, The power converter device used for vehicles, such as a construction machine, It can also be applied to.

  In addition, the present invention can be applied in various modifications within the scope of the gist of the present invention. In short, the outer peripheral side wall is provided on the bottom surface of the case member of the DC-DC converter device, Is at least one side faced directly along one side of the outer peripheral side wall of the case member, and is the low voltage side switching circuit portion placed on the center of the rectangular area of the bottom face portion of the case member? Alternatively, any structure may be used as long as no parts are arranged.

1 Power converter 35, 36 Power semiconductor module (H1-H4, H0)
38 Smoothing capacitor element (Cn)
40 High-voltage circuit board 42 Choke coil (Lc)
50 Low-voltage circuit board 51 Power semiconductor module (S1-S4)
DESCRIPTION OF SYMBOLS 100 DC-DC converter apparatus 101 Case member 102 Bottom face part 103 Transformer (Tr)
104, 105 Choke coil (L1, L2)
106 Noise filter coil (Lf)
107 High-voltage side switching circuit part 108 Low-voltage circuit board part 111a to 111f Partition wall 115 Outer peripheral side wall 115a, 115b Long side 115c, 115d Short side 121-124 Bus bar 131 Housing part 141 Resin 150 Low voltage side switching circuit part 151 Flow path Wall 152 Opening 200 Inverter CTR Control circuit

Claims (15)

With a transformer,
A high-voltage side switching circuit connected to the primary side of the transformer;
A low-voltage circuit board unit connected to the secondary side of the transformer, and a low-voltage side switching circuit unit including at least one choke coil;
A case member that houses the transformer, the high-voltage side switching circuit unit, and the low-voltage side switching circuit unit ;
The case member has a bottom surface portion and an outer peripheral side wall formed by rising along the outer periphery of the bottom surface portion,
At least the transformer is arranged so that at least one side face directly along one side of the outer peripheral side wall of the case member,
Wherein the over the center of the rectangular area of the bottom portion of the case member, the DC-DC converter device, wherein a low-voltage circuit board portion is disposed. The DC-DC converter device according to claim 1,
The DC-DC converter device characterized in that the height of the transformer and the weight per unit rectangular area are larger than the height of the low-voltage circuit board part and the weight per unit area, respectively. The DC-DC converter apparatus according to claim 2,
The case member includes a partition wall member surrounding the periphery of the transformer together with the outer peripheral side wall, and a resin covering the outer peripheral side surface of the transformer is filled in a housing portion constituted by the outer peripheral side wall and the partition wall member . A DC-DC converter device. The DC-DC converter device according to claim 1,
The at least one first choke coil has at least one side surface disposed along one side of the outer peripheral side wall of the case member, and the height and weight per unit area of the first choke coil are respectively The DC-DC converter apparatus characterized by being larger than the height of the said low voltage circuit board part, and the weight per unit area. The DC-DC converter device according to claim 4,
The case member includes a first partition wall member surrounding the outer periphery of the transformer together with the outer peripheral side wall, and a second partition wall member surrounding the outer periphery of the first choke coil together with the outer peripheral side wall, The first housing part constituted by the outer peripheral side wall and the first partition wall member is filled with resin covering the outer peripheral side surface of the transformer, and the second accommodating part is constituted by the outer peripheral side wall and the second partition wall member. A DC-DC converter device characterized in that a resin that covers an outer peripheral side surface of the first choke coil is filled in the housing portion. The DC-DC converter device according to claim 4,
The low voltage side switching circuit unit further includes a second choke coil connected in parallel with the first choke coil, and at least one side of the second choke coil is one side of the outer peripheral side wall of the case member. The DC is arranged along a side, and the height and weight per unit area of the second choke coil are larger than the height and weight per unit area of the low-voltage circuit board part, respectively. -DC converter device. The DC-DC converter device according to claim 6,
The case member includes a first partition wall member surrounding the outer periphery of the transformer together with the outer peripheral side wall, a second partition wall member surrounding the outer periphery of the first choke coil together with the outer peripheral side wall, and the outer peripheral side wall. And a third partition wall member surrounding the outer periphery of the second choke coil, and the outer peripheral side surface of the transformer is covered in a first housing part constituted by the outer peripheral side wall and the first partition wall member. Filled with resin, filled with resin covering the outer peripheral side surface of the first choke coil in the second accommodating portion constituted by the outer peripheral side wall and the second partition wall member, and the outer peripheral side wall and the third A DC-DC converter device characterized in that a third housing part constituted by a partition wall member is filled with a resin covering an outer peripheral side surface of the second choke coil. The DC-DC converter device according to claim 6,
Furthermore, a first bus bar connecting the low-voltage circuit board part and the transformer, a second bus bar connecting the low-voltage circuit board part and the first choke coil, the low-voltage circuit board part, and the A DC-DC converter device comprising: a third bus bar for connecting the second choke coil. The DC-DC converter device according to claim 1,
Furthermore, a noise filter coil for canceling noise components is provided after the choke coil, and the noise filter coil is disposed between the outer peripheral side wall of the case member and the low voltage circuit board portion. The DC-DC converter apparatus characterized by the above-mentioned. The DC-DC converter device according to claim 9,
The DC-DC converter device further includes a fourth bus bar for connecting the noise filter coil and the low-voltage circuit board unit. The DC-DC converter device according to claim 1,
The DC-DC converter device according to claim 1, wherein at least one short side of the low voltage circuit board portion is directly opposed along one side of the outer peripheral side wall of the case member. The DC-DC converter apparatus according to claim 11,
The DC-DC converter device according to claim 1, wherein the one short side of the low-voltage circuit board portion faces an outer peripheral side wall different from the outer peripheral side wall facing the transformer. The DC-DC converter apparatus according to claim 11,
The DC-DC converter device characterized in that the high-voltage side switching circuit section is arranged so that the longitudinal direction thereof is substantially perpendicular to the low-voltage circuit board section. A DC-DC converter device according to any one of claims 1 to 13,
An inverter device fixed to the bottom surface portion of the DC-DC converter device,
A power conversion device, wherein a cooling flow path through which a cooling medium flows is formed at a boundary portion between a bottom surface portion of the DC-DC converter device and the inverter device. The power conversion device according to claim 14, wherein
The cooling flow path is formed along the inner peripheral surface of the case of the inverter device, and protrudes from the cooling flow path to the bottom surface of the DC-DC converter device. A flow path wall that divides the flow path, and an opening that communicates the first flow path and the second flow path, and the cooling medium that flows through the first flow path is the flow path. A power conversion device, wherein the power conversion device is circulated so as to return from the first flow path to the second flow path through the opening by being blocked by a wall.