JP2000196214A - Power electronic circuit device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power electronic circuit device reducing wiring impedance and realizing high density mounting with simple constitution. SOLUTION: The terminals 7d and 7e of a circuit part 7 installed on a circuit board 30 are connected by booth bars 17 and 18 by rigid wiring bodies 17e and 18e which droop from the main face of the booth bar 17, and which are closely brought into contact with the electrode terminal of the circuit part 7. The rigid wiring bodies 17e and 18e use branching conduction parts branched from a conduction pin or the booth bars 17 and 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power electronic circuit device having a bus bar.

[0002]

2. Description of the Related Art Conventionally, in a power electronic circuit device, a power circuit component (for example, a transformer, a choke coil, a power transistor, etc.) for transmitting and receiving a large power, and a low power circuit component (for example, a small semiconductor element, a small capacitor). , Small resistors, etc.) are mounted at high density on the mounting surface of the circuit board.

Power transmission between power circuit components (eg, transformers, choke coils, power transistors, etc.)
Normally, terminals of these power circuit components are fastened to a bus bar extending above the circuit board, and the connection between the terminals of the small power circuit components is usually made by a conductor pattern formed on the circuit board. Further, the connection between the terminal of the small power circuit component and the terminal of the power circuit component is usually made with a cable.

[0004] From the viewpoint of high-density mounting, the busbar has a parallel extension type in which the main surface extends parallel to the circuit board, and a right-angle extension type in which the main surface extends at right angles to the circuit board. And are mainly used. In the former case, the screw for fastening the bus bar and the terminal of the power circuit component can be carried out from a direction perpendicular to the main surface of the circuit board, so that the work is much easier than the latter and the height of the circuit device is reduced. There is an advantage that it can be reduced.

[0005]

However, in the cable connection between the terminals of the low-power circuit components and the terminals of the power circuit components described above, the terminals of the low-power circuit components are guided to the terminal block by a conductor pattern. Cable connection between the terminal of the terminal block and the terminal of the power circuit component requires a large space, which is an obstacle to high-density mounting.

There is another problem that the length of the cable between the terminal of the terminal block and the terminal of the power circuit component increases to increase the wiring impedance. The present invention has been made in view of the above problems, and an object of the present invention is to provide a power electronic circuit device capable of reducing wiring impedance and realizing high-density mounting with a simple configuration.

[0007]

According to the power electronic circuit device of the present invention, the connection between the terminal of the circuit component (the above-mentioned small power circuit component) provided on the circuit board and the bus bar is established. A bus bar (preferably connecting between terminals of a plurality of power circuit components) is connected to at least a wiring body hanging from the bus bar to a circuit board.

Further, a bus bar is extended above the small power circuit component so that the main surface is substantially parallel to the circuit board,
The wiring body is protruded from the bus bar toward the circuit board. It should be noted that “upward” in this specification means a position that is separated from the mounting surface of the circuit board by a predetermined distance. In this way, a two-story structure of low-power circuit components and busbars can be realized, and the busbars and the circuit components directly under the busbars can be connected with a short wiring length, so that the wiring impedance can be reduced and high-density mounting can be achieved. Becomes easier. That is, since the wiring impedance of the bus bar is remarkably small, it can be considered that the generated wiring impedance is substantially equal to that of the wiring body, and this wiring body is connected to the terminal of the bus bar and the terminal of the circuit component or the wiring on the circuit board connected thereto. To the conductor for almost the shortest distance,
The reduction of the wiring impedance can be realized.

In addition, since a cable for which wiring work is complicated is not used, the work becomes easy. Further, since the bus bar can be of a parallel extension type whose main surface extends in parallel with the circuit board, the height of the circuit device is reduced as compared with the case where the main surface extends at right angles to the circuit board. it can. According to the configuration described in claim 2, in the power electronic circuit device according to claim 1, the wiring body further passes through a through hole provided in the bus bar whose main surface extends substantially parallel to the circuit board. Since it is composed of the conductor pins reaching the wiring pattern, its wiring impedance can be reduced.

According to the third aspect of the present invention, in the power electronic circuit device according to the second aspect, the conductor pins are inserted into the through holes provided in the circuit board, so that the wiring body can be easily assembled. . According to the configuration described in claim 4, in the power electronic circuit device according to claim 1, the wiring body further includes:
It is composed of a branching conductor formed by cutting and bending a part of the parallel extending portion provided at a portion other than both end portions of the bus bar toward the circuit board, so that a wiring body is manufactured, and connection and fixing with the bus bar are performed. The work becomes simple.

According to a fifth aspect of the present invention, in the power electronic circuit device according to any one of the first to fourth aspects, the wiring body (for example, a branched conductor portion or a conductor pin) may further include:
For example, since the terminal is in direct contact with both end surfaces of a circuit component having electrode terminals at both ends, such as a chip component, connection between the bus bar and the circuit component is facilitated. According to a sixth aspect of the present invention, in the power electronic circuit device according to the fifth aspect, the branching conductors of the pair of busbars sandwich both end surfaces of the circuit component, so that the soldering is performed by the elasticity of the branching conductors. The branching conductor and the terminal of the circuit component can be satisfactorily connected without attachment.

The bus bar according to the present invention can also serve as a choke coil or a coil conductor of a transformer.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a DC-DC converter device as an example of a power electronic circuit device of the present invention will be described with reference to the following embodiments.

[0014]

Embodiment 1 A DC-DC converter device as an embodiment of a power electronic circuit device of the present invention will be described with reference to a circuit diagram shown in FIG. (Circuit Configuration) This DC-DC converter device is for converting the voltage of a main battery 1 for storing the traveling energy of an electric vehicle to an auxiliary device battery 2 for supplying power to an auxiliary device and a control device and supplying power. 3 is a smoothing capacitor, 4 is an inverter circuit formed by connecting four MOS transistors 4a in a bridge, 6 is a step-down transformer, 7 is a snubber circuit,
Reference numeral 8 denotes two diodes for full-wave rectification, 9 denotes a smoothing circuit including a choke coil 10 and a smoothing capacitor 11, 1
Reference numeral 2 denotes an integrated control circuit.

The high-side terminal of the main battery 1 is a cable 1
3 is connected to an input terminal 14, and a lower terminal of the main battery 1 is connected to a cable 15 through an input terminal 16. The smoothing capacitor 3 has two input terminals 14, 16
A cable 13 is connected to a drain electrode terminal of a pair of MOS transistors 4a on the upper arm side forming a high DC input terminal of the inverter circuit 4, and a cable 15 is connected to a lower arm forming a low DC input terminal of the inverter circuit 4. It is connected to the source electrode terminals of a pair of MOS transistors 4a on the side. The gate electrode of each MOS transistor 4a of the inverter circuit 4 has a built-in circuit for amplifying the input control voltage.

A pair of AC output terminals of the inverter circuit 4 are connected to a primary coil of the step-down transformer 6. A bus bar 17 formed integrally with the secondary coil of the step-down transformer 6 and extending from one end of the secondary coil is connected to one anode electrode terminal of the pair of diodes 8.

A bus bar 18 formed integrally with the secondary coil of the step-down transformer 6 and extending from the other end of the secondary coil
Is connected to the other anode electrode terminal of the pair of diodes 8 and is connected to the intermediate terminal 6a of the secondary coil of the step-down transformer 6.
(See FIG. 2). The auxiliary battery 2 is connected to the bus bars 19, 20 and an output terminal 21 formed at one end of the bus bar 20.
Is connected to the terminal on the lower side.

The bus bar 17 is connected to one end of the snubber circuit 7 through a conductor pin (wiring body in the present invention) 22,
The bus bar 18 is connected to the other end of the snubber circuit 7 through a conductor pin (wiring body in the present invention) 23. The cathodes of the diodes 8 are connected to one end 24 of the choke coil 10, and the other end 25 of the choke coil 10 is connected to a busbar 26, an output terminal 27 formed at one end of the busbar 26, and a high-side terminal of the auxiliary battery 2. It is connected to the. Both ends of the smoothing capacitor 11 are connected to output terminals 21 and 27 through bus bars (not shown). (Explanation of Operation) The control circuit 12 interrupts each MOS transistor 4a of the inverter circuit 4 until the voltage of the auxiliary battery 2 reaches a predetermined value in response to the input of a charging command to its input terminal (not shown). A rectangular wave AC voltage is applied to the coil, thereby outputting a full-wave rectified voltage between the cathode of the diode 8 and the bus bar 19, and applying the DC voltage smoothed by the smoothing circuit 9 to the auxiliary battery 2.

The smoothing capacitor 3 reduces the fluctuation of the discharge current of the main battery 1 due to the intermittent operation of the inverter circuit 4,
The snubber circuit 7 is a high-frequency surge absorbing circuit component including a CR high-pass filter. (Arrangement of Circuit Components) FIG. 2 shows a plane arrangement of each circuit component described above.

Reference numeral 30 denotes a circuit board having a substantially rectangular outer edge, which has a substantially rectangular square notch 31 opening on the left side in FIG. 2 and a through window 32 opening substantially at the center. . The circuit board 30 includes an aluminum base plate 33
And extends parallel to and at a predetermined distance from the main surface of the aluminum base plate 33. Circuit board 30
Is fastened from the aluminum base plate 33 to a column (not shown) standing upright on the back side of the circuit board 30 by screws 34.

A pair of diode 8 and choke coil 1
Numeral 0 is fixed on an aluminum base plate 33 for cooling, and protrudes from the rectangular cutout 31 above the circuit board 30 as shown in FIG. The transformer 6 is also fixed on the aluminum base plate 33 for cooling, and protrudes above the circuit board 30 from the through window 32 as shown in FIG.

The smoothing capacitors 3 and 11, the IC module 12 forming a control circuit, and the like are mounted on the upper surface of the circuit board 30. The bus bars 20 and 26 have terminal blocks at both ends, and fixing projections (not shown) extending from the bus bars 20 and 26 are inserted into through holes provided in the circuit board 30. Is fixed by soldering. The bus bar 19 is fastened to the terminal block of the bus bar 20 over the bus bar 18 forming the end of the secondary coil of the transformer 6.

In FIG. 2, the right end portion 33a of the aluminum base plate 33 projects from the main surface thereof toward the circuit board 30, and
It serves as a heat sink for the MOS transistor 4a. (Main Structure) The main structure of the apparatus of this embodiment is shown in FIG.
This will be described with reference to FIG. In this embodiment, the snubber circuit 7 is provided directly below the bus bars 17 and 18, and both terminals of the snubber circuit 7 are individually soldered to a pair of conductor patterns (not shown) of the circuit board 30 (not shown).
One of these conductor patterns is provided at least immediately below the through hole 17a of the bus bar 17, and the other of these conductor patterns is provided at least immediately below the through hole 18a of the bus bar 18.

The conductor pin 22 is formed in the through hole 1 of the bus bar 17.
7a and the through hole 30a of the circuit board 30 are soldered to the bus bar 17 and the conductor pattern of the circuit board, whereby the bus bar 17 is connected to one end of the snubber circuit 7 through the conductor pin 22 and the conductor pattern. ing. The same applies to the conductor pins 23, which pass through the through holes 18a of the bus bar 18 and the through holes (not shown) of the circuit board 30, and are soldered to the bus bar 18 and the conductor pattern (not shown) of the circuit board. As a result, the bus bar 18
The conductor pin 23 is connected to the other end of the snubber circuit 7 through a conductor pattern. (Operation and Effect) According to the above-described configuration, the bus bars 17, 1
8 is individually connected to the pair of conductor patterns of the circuit board 30 directly below by suspending the conductor pins 22 and 23.
The length of the wiring can be reduced as compared with the case where these conductor patterns are individually connected to both anode terminals of the diode 8 shown in FIG. Performance can be improved. (Modification) In the above embodiment, the conductor pin 22 penetrates the through-hole 17a of the bus bar 17 and the through-hole 30a of the circuit board 30. However, as shown in FIG. May be fixed with solder, and the tip of the conductor pin 22b may be inserted into the through hole 17a provided in the bus bar 30. (Modification) In the above embodiment, the conductor pin 22 is provided separately from the bus bar 17, but as shown in FIG.
A part of the conductor pin (wiring body in the present invention) 1
7c, and the conductor pins 17c may be used as a conductor pattern of the circuit board 30.

This makes it possible to omit the step of connecting the bus bar 17 and the conductor pin 17c. (Modification) In the embodiment of FIG. 5, the tip of the conductor pin 17c is inserted into the through hole 30a of the circuit board 30, but as shown in FIG. A terminal block 40 having a forked portion may be provided, and the tip of the conductor pin 17c may be press-fitted into the forked portion of the terminal block 40.

By doing so, the conductor pins 17c and 30c
Can be simplified. (Modification) In the embodiment of FIG. 6, the tip of the conductor pin 17c is inserted into the through hole 30a of the circuit board 30, but as shown in FIG. The base 41 may be provided, and the tip of the conductor pin 17d may be fastened to the female screw hole of the terminal base 41 with a screw.

This makes it possible to simplify the process of connecting the conductor pins 17c to the conductor patterns on the circuit board 30. (Modification) In each of the above embodiments, the conductor pins are connected to the conductor pattern on the circuit board or the terminal block connected to the conductor pattern. However, as shown in FIG. Power circuit components) 7 terminals 7c, 7
d is bent upward, and the through holes 17a, 1
8a and may be soldered. In this embodiment, the main body of the snubber circuit is fixed to the circuit board 30 with a solder paste or the like. (Modification) In the embodiments shown in FIGS.
Although c or 17d is electrically connected to the conductor pattern of the square notch 310 or the terminal block connected thereto, in the embodiment shown in FIG. 9, for example, a snubber circuit having electrode terminals 7d and 7e at both ends like a chip component 7 is the circuit board 3
0, and the branching conductor portions 17 of the bus bars 17 and 18 are fixed.
The electrical connection with the electrode terminals 7d and 7e is performed by bringing the tips of the electrodes e and 18e into close contact with both side surfaces of the snubber circuit 7. 50 is a soldering part.

This eliminates the need for a conductor pattern or a terminal block, simplifies the connection work, and further reduces the wiring length. Further, the heat generated by the snubber circuit 7 is favorably transmitted through the branch conductors 17e and 18e.
18 can be dissipated. In this modification, the conductor pins as shown in FIG. 3 can be directly brought into close contact with the electrode terminals 7d and 7e of the snubber circuit 7 as a chip component.

Further, in FIG.
The distance between the branch conductors 17e, 18e is set slightly smaller than the length of the snubber circuit 7, and the elasticity of the branch conductors 17e, 18e does not require the soldering portion 50.
Good electrical connection between the electrode terminal 8e and the electrode terminals 7d, 7e of the snubber circuit 7 can also be ensured.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a DC-DC converter for an electric vehicle as one embodiment of a power electronic circuit device of the present invention.

FIG. 2 is a plan view of the DC-DC converter device shown in FIG.

FIG. 3 is a sectional view of a main part of the DC-DC converter device shown in FIG. 2;

FIG. 4 is a cross-sectional view of a main part showing a modification of the DC-DC converter device shown in FIGS. 2 and 3;

FIG. 5 is a perspective view of a main part showing a modification of the DC-DC converter device shown in FIGS. 2 and 3;

6 is a main part side view showing a modification of the DC-DC converter device shown in FIGS. 2 and 3. FIG.

FIG. 7 is a main part side view showing a modification of the DC-DC converter device shown in FIGS. 2 and 3;

FIG. 8 is a cross-sectional view of a main part showing a modification of the DC-DC converter device shown in FIGS. 2 and 3;

9 is a main part side view showing a modification of the DC-DC converter device shown in FIGS. 2 and 3. FIG.

[Explanation of symbols]

7 is a snubber circuit (circuit component), 30 is a circuit board, 17,
18 is a bus bar, 22 and 23 are conductor pins (wiring bodies) 30
a is a through hole of the circuit board 30, 17c, 17d, 17e,
18e is a branching conductor (wiring body)

Claims (6)

[Claims] A circuit board on which a circuit component is mounted on a mounting surface; and a parallel extending portion extending above the circuit component in a posture in which a main surface is substantially parallel to a mounting surface of the circuit board. A bus bar, and a wiring body protruding from one end connected to the parallel extending portion of the bus bar at a substantially right angle to the main surface of the bus bar and connected to a wiring pattern of the circuit board. Power electronic circuit device. 2. The power electronic circuit device according to claim 1, wherein the wiring body passes through a through hole provided in the bus bar whose main surface extends substantially parallel to the circuit board. A power electronic circuit device, comprising: a conductor pin reaching at least one of the following. 3. The power electronic circuit device according to claim 2, wherein said conductor pin is inserted into a through hole provided in said circuit board. 4. The power electronic circuit device according to claim 1, wherein the wiring body cuts and bends a part of the parallel extending portion provided at a portion other than both ends of the bus bar toward the circuit board. An electronic circuit device for electric power, comprising a branched conductor portion formed by: 5. The power electronic circuit device according to claim 1, wherein the circuit component has electrode terminals at both ends, and the wiring body is in contact with both end surfaces of the circuit component. Power electronic circuit device. 6. The power electronic circuit device according to claim 5, wherein said branched conductor portions of said pair of bus bars sandwich both end faces of said circuit component.