JPH09285008A - Circuit device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a circuit device of a simple structure which makes it possible to achieve miniaturizing and reduction in production cost. SOLUTION: DC input terminal blocks 21, 22, which supply a DC power to semiconductor devices 12a, 12b, 12c, 13, 14, are provided near an opposed space formed between the semiconductor devices 12a, 12b, 12c and semiconductor device 3, 4. Power supply smoothing capacitors 31, 32, 33, 34 are provided above and near the semiconductor devices 12a, 12b, 12c. Because shortened extension for electrical connection between the semiconductor devices 12a, 12b, 12c, 13, 14 and the power supply smoothing capacitors 31, 32, 33, 34 reduces the wiring inductance, a surge voltage generated by switching is lowered. As a result, the surge voltage is enabled to be lowered with fewer number of the power supply smoothing capacitors so that miniaturizing and reduction in production cost of a control device 1 is achievable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit device, and more particularly to a circuit device used in a control device for an electric vehicle.

[0002]

2. Description of the Related Art Conventionally, when a circuit device requiring a plurality of semiconductor devices is mounted on a common cooler, for example, a terminal block and a circuit breaker are fixed near a DC power input portion on the semiconductor device mounting surface. A base or the like is provided, and wiring is branched from each to each semiconductor device to supply power to each semiconductor device.
Further, in a circuit device in which a surge voltage is generated by driving a semiconductor device, a power supply smoothing capacitor may be connected to the DC power input section in order to smooth the surge voltage.

Particularly, in a circuit device for converting DC power into high frequency switching to AC power, it is necessary to connect a power supply smoothing capacitor between DC input lines in order to absorb a surge voltage generated at each switching of semiconductor elements. . The surge voltage increases in proportion to the wiring inductance between the input terminal of the semiconductor element that constitutes the semiconductor device and the input terminal of the power supply smoothing capacitor.Therefore, in order to suppress the magnitude of the surge voltage, the input terminal of the semiconductor element and the power source It is necessary to reduce the wiring length between the input terminals of the smoothing capacitor to reduce the wiring inductance. Therefore, in the conventional circuit device in which the wiring is branched to each semiconductor device to supply power to each semiconductor device, by connecting the power supply smoothing capacitor to each semiconductor device in the vicinity of each semiconductor device, The wiring inductance between the input terminal of and the input terminal of the power smoothing capacitor is reduced to absorb the surge voltage.

[0004]

However, in the conventional circuit device as described above, the wiring to each semiconductor device is complicated and it is difficult to save the wiring space. Furthermore, since the wiring length to each semiconductor device becomes long, the wiring inductance becomes large, and the surge voltage generated becomes high, so that it is necessary to increase the number of power supply smoothing capacitors to be attached to the circuit device. For the reasons described above and, it is difficult to reduce the size and cost of the conventional circuit device.

The present invention has been made in order to solve such a problem, and an object thereof is to provide a circuit device which can be downsized and reduced in cost with a simple structure. Another object of the present invention is to provide an electric vehicle control device that can be downsized and reduced in cost with a simple configuration.

[0006]

According to the circuit device of the first aspect of the present invention, a common space is formed between the facing space formed between the first semiconductor device and the second semiconductor device and in the vicinity thereof. By supplying DC power from the DC input terminal member to the first semiconductor device and the second semiconductor device via the branch terminal, the electrical connection length between the semiconductor elements forming each semiconductor device is shortened. Further, by disposing the power supply smoothing capacitor near the upper part of the first semiconductor device, the electrical connection length between the first semiconductor device and the power supply smoothing capacitor is shortened. Therefore, the wiring inductance between the first semiconductor device and the power supply smoothing capacitor and between the second semiconductor device and the power supply smoothing capacitor becomes low, so that a surge that occurs in the first semiconductor device and the second semiconductor device with a small number of power supply smoothing capacitors. The voltage can be smoothed. As a result, the circuit device can be downsized and reduced in cost with a simple configuration.

According to the circuit device of the second aspect of the present invention, it is possible to reduce the number of power supply smoothing capacitors to be attached to the switching device in which surge voltage is easily generated. According to the circuit device of claim 3 of the present invention, the electrical connection length between the first semiconductor device that generates a high surge voltage and the power supply smoothing capacitor becomes short, so that the surge voltage is effectively smoothed with a small number of power supply smoothing capacitors. it can.

According to the configuration of claim 4 of the present invention, the number of power supply smoothing capacitors mounted on the control device for an electric vehicle can be reduced, so that the control device can be downsized and reduced in cost with a simple configuration.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) A first embodiment in which the circuit device of the present invention is applied to a control device for an electric vehicle is shown in FIGS. 1, 2 and 3.

A coolant passage (not shown) is provided in the cooling plate 5 of the circuit device 1 shown in FIG. 1, and the electric components mounted on the cooling plate 5 are cooled by the refrigerant introduced into and discharged from the cooling plate 5. It On the first mounting surface 5a of the cooling plate 5, the first motor for controlling the drive motor 11 of the electric vehicle (see FIG. 3) is provided.
Semiconductor elements 12a, 12b, 12c constituting a semiconductor device 2 as a semiconductor device are attached. On the second mounting surface 5b adjacent to the first mounting surface 5a, the semiconductor elements 13 and 14 forming the second semiconductor device are mounted.
The semiconductor element 13 constitutes the semiconductor device 3, and the semiconductor element 1
Reference numeral 4 constitutes the semiconductor device 4. The cooling plate 5 is for radiating heat generated when the semiconductor elements 12a, 12b, 12c, 13, 14 are driven. Semiconductor element 12
semiconductor elements 12a, 12b, 1 in the vicinity of the facing space formed between a, 12b, 12c and the semiconductor elements 13, 14.
As shown in FIGS. 1 and 2, DC input terminal plates 21 and 22 as DC input terminal members are provided on 2c. The DC input terminal plates 21 and 22 are arranged so as to extend along the respective facing surfaces of the semiconductor device 2 and the semiconductor devices 3 and 4.

As shown in FIG. 3, semiconductor elements 12a, 1
Reference numerals 2b and 12c are semiconductor switching elements that form a known inverter circuit that converts direct-current power from the on-vehicle battery 15 into three-phase alternating-current power and controls the drive motor 11 of the electric vehicle. The semiconductor elements 13 and 14 are switching elements that configure the semiconductor devices 3 and 4 that supply power to the other loads 16 and 17, respectively. The semiconductor elements 13 and 14 have lower driving power than the semiconductor elements 12a, 12b, and 12c. In this embodiment, an IGBT module is assumed as each semiconductor element.

The DC input terminal plates 21 and 22 are semiconductor elements 1.
DC power is supplied to 2a, 12b, 12c, 13 and 14, and the semiconductor element 1 in the vicinity of the facing space described above is provided.
It is arranged above the 2a, 12b, and 12c. DC power is supplied from the vehicle-mounted battery 15 to the DC input terminal plates 21 and 22. As shown in FIG. 1, the DC input terminal plate 21 on the positive electrode side has branch terminals 23, 25, 2 on the positive electrode side.
7 are connected to each other, and branch terminals 24, 26, 28 on the negative electrode side are electrically connected to the DC input terminal plate 22 on the negative electrode side. Branch terminals 23, 24, 25, 26, 2
7 and 28 can be formed integrally with the DC input terminal plates 21 and 22, or can be formed separately from the DC input terminal plates 21 and 22 and connected by screws.

The branch terminal 23 on the positive electrode side and the branch terminal 24 on the negative electrode side are respectively semiconductor elements 12a, 12b and 12c.
It is directly electrically connected to. Branch terminal 25 on the positive electrode side,
27 and the branch terminals 26 and 28 on the negative electrode side are the semiconductor element 1
3 and 14 are directly electrically connected. The power supply smoothing capacitors 31, 32, 33, 34 are the semiconductor elements 12a, 12
b, 12c, and DC input terminal plate 21,
22 is electrically connected. As a result, the semiconductor element 12 of the power supply smoothing capacitors 31, 32, 33, 34 is
The electrical connection length with a, 12b, and 12c is the semiconductor element 1
It is shorter than the electrical connection length with the electrodes 3 and 14. First
Semiconductor elements 12a, 12b, 1 constituting the semiconductor device 2
2c controls the drive motor 11, so that the semiconductor element 1
This means that it controls a larger electric power than Nos. 3 and 14. Therefore, since the surge energy of the semiconductor elements 12a, 12b, 12c is larger than the surge energy of the semiconductor elements 13, 14, the electrical connection between the semiconductor elements 12a, 12b, 12c and the power source smoothing capacitors 31, 32, 33, 34 is made. The surge voltage generated by shortening the length and reducing the wiring inductance can be reduced.

In FIGS. 1 and 2, the semiconductor element 12 is shown.
AC wiring and semiconductor elements 12a, 12b, 12c, 1 for supplying electric power from the output terminals of a, 12b, 12c, 13 and 14 to the driving motor 11 and the loads 16 and 17.
A control circuit board for controlling the driving of 3 and 14 is not shown. It is also possible to additionally mount a plurality of semiconductor devices as other semiconductor devices mounted on the second mounting surface 5b.

Next, the operation of the circuit device 1 will be described.
The DC power of the on-vehicle battery 15 is the semiconductor elements 12a, 12
In b and 12c, it is converted into AC power by high frequency switching and supplied to the drive motor 11. Semiconductor device 13,
14 also carries out high frequency switching of the DC power of the on-vehicle battery 15 to convert it into AC power and supplies it to the loads 16 and 17. When the semiconductor elements 12a, 12b, 12c, 13 and 14 perform high frequency switching of DC power, a rapid current change occurs, so that the semiconductor elements 12a, 12b, 12c, 1
3, 14 and power smoothing capacitors 31, 32, 33, 34
A surge voltage is generated in proportion to the size of the wiring inductance between and. If the surge voltage is semiconductor elements 12a, 12
If the voltage is excessively applied to b, 12c, 13 and 14, the semiconductor elements 12a, 12b, 12c, 13 and 14 may be destroyed. In order to reduce the surge voltage, as described above, the semiconductor elements 12a, 12b, 12c, 13, 14 are used.
The wiring inductance between the power supply smoothing capacitors 31, 32, 33 and 34 may be reduced as much as possible.

Next, the effect of the first embodiment will be described as compared with the comparative example shown in FIG. In the comparative example shown in FIG. 4, the semiconductor elements 12a, 12b, 12c, 13, 14 are individually wired, and the semiconductor elements 12a, 12b, 12c, 1
The wiring length between 3 and 14 is long and the wiring inductance is also large. Therefore, the surge voltage generated by switching also increases, so that the semiconductor elements 12a, 12b, 12
It is necessary to dispose power supply smoothing capacitors 35 and 36 in the vicinity of the semiconductor elements 13 and 14 as well as in the vicinity of c to absorb the surge voltage.

On the other hand, in the first embodiment, the DC input terminal plate 21, is formed on the semiconductor elements 12a, 12b, 12c near the facing space formed between the semiconductor device 2 and the semiconductor devices 3, 4.
22 is provided and the branch terminals 23, 24, 25, 26, 27, 28 provided on the DC input terminal plates 21, 22 and the semiconductor elements 12a, 12b, 12c, 13, 14 are electrically connected in a short distance. Therefore, the semiconductor elements 12a, 12b,
The wiring inductance between 12c, 13 and 14 is small.
Therefore, the four power supply smoothing capacitors 31, 32, 33, 3 arranged on the semiconductor elements 12a, 12b, 12c.
4 only semiconductor elements 12a, 12b, 12c, 13, 1
Since the surge voltage generated in No. 4 can be favorably absorbed, the number of power supply smoothing capacitors is reduced, and the circuit device can be downsized and the cost can be reduced.

(Second Embodiment) A second embodiment of the present invention is shown in FIG.
Shown in Components substantially the same as those in the first embodiment are denoted by the same reference numerals. Although the DC input terminal board 21 and the DC input terminal board 22 of the first embodiment are insulated by air, the DC input terminal board 21 and the DC input terminal board 22 of the second embodiment have the insulator 41 between them. It has a structure of a laminated conductor which is sandwiched and laminated. Therefore, the inductance of the DC input terminal plates 21 and 22 can be reduced as compared with the structure which is insulated by air and does not have the structure of the laminated conductor as in the first embodiment. Therefore, it is possible to use a capacitor that has a smaller surge absorbing capacity than the power supply smoothing capacitor of the first embodiment, that is, a capacitor that has a small capacity and can be miniaturized.
The physique can be further miniaturized.

In the above-described embodiment of the present invention described above, since power is supplied to each semiconductor element from the common DC input terminal plates 21 and 22, the wiring is simplified and the circuit device as a whole is miniaturized. Further, there is an effect that the weight can be reduced and the cost can be reduced. Further, the power supply smoothing capacitors 31, 32, 33, 34 are arranged close to the semiconductor elements 12a, 12b, 12c, which have a relatively large driving power as compared with the driving power of the semiconductor elements 13, 14 and a large surge voltage generated by switching. As a result, the electrical connection length between the semiconductor elements 12a, 12b, 12c and the power supply smoothing capacitors 31, 32, 33, 34 is shortened and the wiring inductance is reduced, so that the surge voltage is reduced and the surge voltage can be absorbed well. .

Furthermore, since the DC power is branched from the DC input terminal plates 21, 22 to the semiconductor devices 2, 3, 4, there is no need for a terminal block for branching on the semiconductor element mounting surface. Therefore, it is possible to reduce the size and cost of the circuit device. In this embodiment, the DC input terminal member is formed in a plate shape, but the shape of the DC input terminal member is not limited to a plate shape as long as electric power can be commonly supplied to each semiconductor device.

Further, in this embodiment, the semiconductor elements 12a, 12b, 12c were described as the known IGBT module in which one AC phase is contained in one case, but three AC phases are contained in one case. It may be an IGBT module. Also, a known IGBT in which three AC phases are contained in one case
Although the semiconductor elements 13 and 14 have been described as modules,
A module in which one AC phase is stored in one case may be used. Further, each semiconductor element may be a MOS-FET or a power transistor.

In the present embodiment, four power supply smoothing capacitors are arranged on the semiconductor elements 12a, 12b, 12c constituting the first semiconductor device, but the surge voltage of each semiconductor element is within the allowable range. It is possible to reduce the number of power supply smoothing capacitors as long as they are within the range. It is also possible to reduce the capacity of the power supply smoothing capacitors and increase the number thereof.

In this embodiment, only the on-vehicle battery is handled as the DC power supply source, but it is also possible to supply DC obtained by rectifying AC. Further, the cooling system may be a liquid cooling system in which a cooling liquid is caused to flow in the cooling plate, or fining may be applied to the cooling plate or an air cooling system may be attached to a separate fin for air cooling. A heat pipe system in which a heat pipe is provided inside the cooling plate may be used.

[Brief description of drawings]

FIG. 1 is a plan view showing a first embodiment in which a circuit device of the present invention is applied to a control device for an electric vehicle.

FIG. 2 is a view in the direction of arrow II in FIG. 1;

FIG. 3 is a circuit configuration diagram of the present embodiment.

FIG. 4 is a comparative example of the first embodiment.

FIG. 5 is a plan view showing a second embodiment in which the circuit device of the present invention is applied to an electric vehicle control device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Circuit device 2 Semiconductor device (1st semiconductor device) 3, 4 Semiconductor device (2nd semiconductor device) 5 Cooling plate 11 Vehicle-mounted motor (driving motor) 12a, 12b, 12c Semiconductor element (1st semiconductor device) 13, 14 Semiconductor element (second semiconductor device) 21, 22 DC input terminal plate (DC input terminal member) 23, 24, 25, 26, 27, 28 Branch terminal 31, 32, 33, 34 Power supply smoothing capacitor

Claims (4)

[Claims] 1. A semiconductor device having at least a first semiconductor device and a second semiconductor device, and arranged in a space formed between the first semiconductor device and the second semiconductor device and in the vicinity thereof, A direct current input terminal member for supplying a direct current to each semiconductor element constituting the first semiconductor device and the second semiconductor device; and an electrical connection to the direct current input terminal member. A circuit device comprising: a branch terminal that supplies a direct current to the element; and a power supply smoothing capacitor that is disposed near the upper portion of the first semiconductor device. 2. The circuit device according to claim 1, wherein the first semiconductor device and the second semiconductor device are switching devices. 3. The circuit device according to claim 1, wherein the power supplied to the first semiconductor device is larger than the power supplied to the second semiconductor device. 4. A control device for an electric vehicle, wherein the circuit device according to claim 1, 2 or 3 is used in a control device for an electric vehicle, and a drive motor of the electric vehicle is controlled by the first semiconductor device. .