JP3770482B2 - Power converter for vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle power conversion device used as a vehicle single-phase or three-phase inverter circuit or a DC-DC converter circuit.
[0002]
[Prior art]
In various types of power vehicles such as internal combustion locomotives, hybrid vehicles, fuel cell vehicles, etc., single-phase or three-phase inverter devices for DC-AC conversion and DC-DC converter devices for DC-DC conversion are used. In such a vehicle power converter, a transformer or a choke coil is indispensable. Since these transformers or choke coils have lower durability due to temperature rise, they are usually fixed to a metal base plate for cooling.
[0003]
Since these transformers or choke coils have a large weight, a large lateral or longitudinal biasing force acts on the transformer or the choke coils due to vehicle vibration. For this reason, conventionally, both ends of the U-shaped holder are fastened to the upper surface of the metal base plate, and the upper side of the transformer or choke coil is pressed at the center of the holder to restrict the lateral and vertical shifts.
[0004]
[Problems to be solved by the invention]
However, in the conventional three-phase inverter device for vehicles and the DC-DC converter device for vehicles described above, the transformer or choke coil must be fixed with the holder one by one, and the work space for fastening the holder to the metal base plate is often narrow. This is troublesome and increases the number of parts.
[0005]
The present invention has been made in view of the above problems, and provides a vehicular power conversion device capable of reducing the number of parts and the number of work steps while preventing a decrease in the displacement prevention performance of a transformer or a choke coil. It is aimed.
[0006]
[Means for Solving the Problems]
The power converter for a vehicle according to the present invention includes a metal base plate for cooling, a transformer or choke coil having a plurality of terminals projecting to the side and having a bottom surface in close contact with the upper surface of the metal base plate, and projecting to the side surface. Or a semiconductor module having a terminal exposed on the top surface and having a bottom surface in close contact with the top surface of the metal base plate to constitute an inverter circuit or a rectifier circuit, and a number of bus bars integrated with an insulating material while being insulated from each other. A bus bar assembly fixed to the metal base plate in a posture parallel to the metal base plate above the metal base plate;
The terminal of the transformer or choke coil and the terminal of the semiconductor module are connected to the end of the bus bar protruding to the side surface or exposed on the upper surface, and the bus bar assembly is configured to prevent lateral displacement of the transformer or choke coil. It has the holder part which controls.
[0007]
According to the present invention, the bus bar assembly in charge of the large current wiring of the power converter for a vehicle including connections to the terminals of the transformer or choke coil and the semiconductor module has a large weight and a large biasing force from the vehicle. Since it has a holder that prevents lateral displacement of the transformer or choke coil to be added, it is possible to prevent lateral displacement of the transformer or choke coil without using a conventional holder by simply fixing the bus bar assembly to the metal base plate by fastening or the like. This can reduce the number of parts and the number of work steps.
[0008]
The holder portion may have a shape that abuts on the side surface of the transformer or the choke coil, or may have a shape that abuts on the upper surface thereof.
[0009]
In a preferred aspect, the holder portion further restricts the vertical shift of the transformer or the choke coil in the direction away from the metal base plate, so that it becomes more effective. The lateral displacement regulating holder portion and the longitudinal displacement regulating holder portion may be integrated or separated.
[0010]
In a preferred aspect, the holder portion extends from the portion of the bus bar assembly located on both sides of the transformer or choke coil to the upper surface of the transformer or choke coil, and is elastically deformed to generate the transformer or choke with a predetermined urging force. Hold the top of the coil. If it does in this way, a lateral shift and a vertical shift can be controlled with a holder part of simple shape.
[0011]
In a preferred aspect, the holder portion includes at least a floating potential bus bar or a ground potential bus bar accommodated in the bus bar assembly. If it does in this way, the elastic biasing force excellent in this bus bar can be given, without making a process complicated.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment in which the vehicle power converter of the present invention is applied to a vehicle DC-DC converter device will be described below with reference to FIG.
(Structure explanation)
This DC-DC converter device for a vehicle is a direct-current voltage conversion circuit that is arranged between an on-vehicle high-voltage battery and a low-voltage battery and transmits power from the high-voltage battery to the low-voltage battery. A single-phase inverter module 1 for converting into a phase AC voltage, a controller 2 for PWM switching control of four power MOS transistors constituting the single-phase inverter module 1, and a single-phase AC voltage output from the single-phase inverter module 1 A step-down transformer 3, a full-wave rectifier circuit module 4 for single-phase full-wave rectification of the output voltage of the step-down transformer 3, a choke coil 5 for smoothing the output voltage of the full-wave rectifier circuit module 4, and a bus bar assembly 6 Have. Since the details of the circuit configuration and operation of this type of vehicle DC-DC converter device are well known and not directly related to the present invention, further explanation is omitted. However, the bus bar assembly 6 having the holder portions 7 and 8 will be described in detail later.
[0013]
However, FIG. 1 is a schematic plan view showing an arrangement state of each circuit component of the DC-DC converter device for a vehicle. A bus bar wiring state, a connection state between the bus bar and each circuit element, and the like will be described later with the controller 2. The portions other than the connection portion with the bus bar assembly 6 are not shown.
[0014]
1 will be described with reference to the longitudinal sectional views of FIGS. 2 to 4. FIG. 2 is a longitudinal sectional view of the vicinity of the single-phase inverter module 1, FIG. 3 is a longitudinal sectional view in the Y direction of the step-down transformer 3, and FIG. 4 is a longitudinal sectional view of the step-down transformer 3 in the X direction. In this embodiment, the single-phase inverter module 1 is used for simplification of illustration, but it is natural that the four power switching transistors of the single-phase inverter circuit may be separately modularized.
[0015]
In FIG. 2, the single-phase inverter module 1 is fixed on an aluminum base plate 9 with screws (not shown) for cooling. Reference numeral 12 denotes one main electrode terminal of the single-phase inverter module 1, which protrudes horizontally from the side surface of the resin-molded main body of the single-phase inverter module 1. The bottom surface of the single-phase inverter module 1 is in close contact with the top surface, which is the component contact surface of the aluminum base plate 9.
[0016]
The bus bar assembly 6 is fixed to the aluminum base plate 9 so as to be parallel to the aluminum base plate 9 at a predetermined interval above the aluminum base plate 9. The bus bar assembly 6 is integrated with a large number of bus bars (only the bus bars 61 and 62 are shown in FIG. 2) arranged in a double-upper manner at predetermined intervals in the thickness direction, while insulating the bus bars from each other. And a resin plate 63 to be used. The bus bar assembly 6 may be formed by resin molding using an IC lead frame, or may be formed by insert resin molding. The bus bar assembly 6 has a window 64. The end portion of the bus bar 61 protrudes horizontally from the side surface of the resin plate 63 facing the window 64, and then is bent and lowered, and is further bent beside the main electrode terminal 12 of the single-phase inverter module 1 to be the main electrode. It extends while contacting the terminal 12.
[0017]
In FIG. 3, the core of the step-down transformer 3 is in close contact with the upper surface, which is a component contact surface of the aluminum base plate 9. The bus bar assembly 6 has leg portions 65, 66 that hang down to the aluminum base plate 9 while being close to both sides of the step-down transformer 3, and the bottom surfaces of the leg portions 65, 66 are on the upper surface that is a component contact surface of the aluminum base plate 9. Closely fastened by bolts 10 and 11. A conductor 31 forming one end of the primary coil of the step-down transformer 3 protrudes to the left and is fastened to the exposed end of the bus bar 67 of the bus bar assembly 6 by a screw 32. The conductor 33 that forms one end of the secondary coil of the step-down transformer 3 protrudes rightward and is fastened to the exposed end of the bus bar 68 of the bus bar assembly 6 by a screw 34.
[0018]
In FIG. 4, the upper surface of the core of the step-down transformer 3 is elastically biased downward by a bus bar 7 that forms a holder portion from the bus bar assembly 6, thereby preventing lateral shift and vertical shift. The holder part 7 is formed of the same copper as the other bus bars of the bus bar assembly 6, and preferably, all the bus bars and the bus bar 7 forming the holder part are formed by punching a copper flat plate. The bus bar (holder part) 7 is not connected to any circuit element or is electrically grounded to the aluminum base plate 9. The bus bar 7 also has the effect of covering and mechanically protecting the core of the step-down transformer 3 and the effect of cooling the core in the same manner as the aluminum base plate 2. The holder portion 8 that elastically urges the choke coil 5 downward has the same structure and function and effect as the holder portion 7 that elastically urges the step-down transformer 3 downward, and thus description thereof is omitted.
(Example effect)
The power circuit device and the manufacturing method thereof according to this embodiment described above can achieve the following effects.
[0019]
According to this embodiment, the bus bar-type holder parts 7 and 8 manufactured in the same process as the bus bar of the bus bar assembly 6 elastically bias the step-down transformer 3 and the choke coil 5 downward to prevent their deviation. Therefore, the effect of preventing the shift of the transformer or choke coil can be obtained while reducing the number of parts and the number of work steps.
[Brief description of the drawings]
FIG. 1 is a schematic plan view of a vehicular DC-DC converter apparatus according to a first embodiment.
2 is a longitudinal sectional view of the vicinity of a single-phase inverter module shown in FIG.
3 is a longitudinal sectional view in the Y direction of the step-down transformer shown in FIG. 1. FIG.
4 is a longitudinal sectional view of the step-down transformer shown in FIG. 1 in the X direction.
[Explanation of symbols]
1 Single-phase inverter module 3 Step-down transformer 5 Choke coil 6 Busbar assembly 7 Holder part 8 Holder part 9 Aluminum base plate

Claims (4)

A metal base plate for cooling;
A transformer or a choke coil having a plurality of terminals projecting laterally and having a bottom surface in close contact with the top surface of the metal base plate;
A semiconductor module having a terminal protruding to the side surface or exposed on the upper surface and having a bottom surface in close contact with the upper surface of the metal base plate to constitute an inverter circuit or a rectifier circuit;
A bus bar assembly formed by integrating a number of bus bars while being insulated from each other by an insulating material and fixed to the metal base plate in a posture parallel to the metal base plate above the metal base plate;
With
The terminal of the transformer or choke coil and the terminal of the semiconductor module are connected to the end of the bus bar protruding to the side surface or exposed on the upper surface,
The bus bar assembly has a holder portion that regulates lateral displacement of the transformer or choke coil. In the vehicle power converter device according to claim 1,
The power conversion device for a vehicle according to claim 1, wherein the holder portion also regulates a vertical shift of the transformer or the choke coil in a direction away from the metal base plate. In the vehicle power converter according to claim 1 or 2,
The holder portion extends from the portion of the bus bar assembly located on both sides of the transformer or choke coil to the upper surface of the transformer or choke coil, and elastically deforms to hold the upper surface of the transformer or choke coil with a predetermined urging force. A vehicular power conversion device. In the vehicle power converter device according to claim 3,
The vehicle power converter according to claim 1, wherein the holder portion includes at least a floating potential bus bar or a ground potential bus bar accommodated in the bus bar assembly.

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