JP2021182828A - Electric power conversion device - Google Patents

Abstract

To provide an electric power conversion device that can be inexpensively manufactured.SOLUTION: An electric power conversion device 100 comprises: a housing 60; a cooler 70 and a circuit board 80 which are arranged side by side inside the housing 60; first circuit components 20a to 20d which are arranged on a first surface 70a on the circuit board 80 side, of the cooler 70; and a second circuit component 10 arranged on a second surface 70b behind the first surface 70a of the cooler 70, a terminal 20at of the first circuit component 20a to 20d is connected to the circuit board 80, and a terminal 10t of the second circuit component 10 is connected to the circuit board 80 through a through-hole 70h provided in the cooler 70.SELECTED DRAWING: Figure 1

Description

The present application relates to a power conversion device.

The power conversion device contains a circuit called a power conversion circuit inside the housing. The power conversion circuit electrically connects the main circuit section through which a large current flows, the control section that controls them, and the components. It is generally composed of a circuit board and a terminal extension member such as a bus bar.

The control unit is mainly composed of sensors, drivers, microcomputers, power supplies for control circuits, etc. driven by low power, and the main circuit unit is mainly composed of switching elements, capacitors, reactors, transformers, etc. for high power applications. A part of the components of the control unit and the main circuit unit is connected to the circuit board.

In addition, since a large current flows in the main circuit section compared to the control section, parts such as transformers, reactors, switching elements, capacitors, and CMC (common mode choke coils) mounted in the main circuit section are used. Since the amount of heat generated is large, a housing in which a heat dissipation base having a heat dissipation fin or a water channel is arranged on the bottom surface is often used for suppressing a temperature rise.

In such a power conversion device in which heat dissipation fins or water channels are arranged on the bottom surface of the housing, generally, high heat generating parts such as a transformer, a reactor, a switching element, a capacitor, and a CMC (common mode choke coil) are placed on the bottom surface of the housing. It has high heat dissipation characteristics because it is arranged and the heat of the high heat generation parts is released to the heat dissipation base on the bottom of the housing. The high heat generation component described above is connected to a circuit board arranged above the high heat generation component via a lead wire, a bus bar, or the like.

Japanese Patent No. 6486443

However, in such a power conversion device, since parts having different heights are arranged on the bottom surface of the housing, low-height parts such as switching elements have a large distance from the substrate, so that a step is provided in the housing. , It is necessary to change the height of the bottom surface of low-height parts. Therefore, there is a problem that the processing cost and the material cost for forming the step are incurred, and the cost of the power conversion device is increased.

For example, Patent Document 1 discloses a configuration in which parts such as a reactor and a capacitor are arranged in a recess formed by providing a step in the housing and electrically connected to the same substrate.

As a method other than providing a step on the bottom surface of the housing, there are a method of arranging a terminal extension member such as a bus bar between a low-height component and a board, and a method of extending the terminal length of a low-height component. Since it is necessary to manufacture a bus bar for the former and a custom product for a semiconductor package with an extended terminal length for the latter, there is still a problem that the cost of the power conversion device is high.

The present application discloses a technique for solving the above-mentioned problems, and an object thereof is to provide a power conversion measure that can be manufactured at low cost.

The power converter disclosed in the present application is
With the housing
The coolers and circuit boards arranged side by side inside the housing,
The first circuit component arranged on the first surface of the cooler on the circuit board side, and
A second circuit component arranged on a second surface behind the first surface of the cooler is provided.
The terminal of the first circuit component is connected to the circuit board and is connected to the circuit board.
The terminal of the second circuit component is connected to the circuit board through a through hole provided in the cooler.

According to the power conversion device disclosed in the present application, it is possible to provide a power conversion measure that can be manufactured at low cost.

It is sectional drawing of the power conversion apparatus by Embodiment 1. FIG. It is a figure which shows the structure of the bridgeless PFC circuit by Embodiment 1. FIG. It is sectional drawing which shows the other structure of the power conversion apparatus by Embodiment 1. FIG. It is sectional drawing which shows the other structure of the power conversion apparatus by Embodiment 1. FIG.

Embodiment 1.
Hereinafter, the power conversion device according to the first embodiment will be described with reference to the drawings.
FIG. 1 is a cross-sectional view of the power conversion device 100.
FIG. 2 is a diagram showing a configuration of a bridgeless PFC (Power Factor Collection) circuit 50 as an example of a power conversion circuit of the power conversion device 100.
The bridgeless PFC circuit 50 includes a PFC reactor 10, a converter 20 for connecting switching elements 20a to 20d in a bridge type, an input power supply 30, and a smoothing capacitor 40. Then, one end of the input power supply 30 is connected to the wiring 1 connecting the switching elements 20a and 20b via the PFC reactor 10. Further, the other end of the input power supply 30 is connected to the wiring 2 connecting the switching elements 20c and 20d.

One end of the smoothing capacitor 40 is connected to the wiring 3 connecting the switching elements 20a and 20c, and the other end is connected to the wiring 4 connecting the switching elements 20b and 20d. The PFC reactor 10 is configured to be connected in series between the input power supply 30 and the wiring 1 connecting the switching elements 20a and 20b. The bridgeless PFC circuit 50 has a function of converting the voltage of the input power supply 30 into the DC voltage Vdc of the smoothing capacitor 40.

FIG. 1 is a cross-sectional view of the power conversion device 100, which is cut off at a portion where the switching element 20a is present. As shown in FIG. 1, the power conversion device 100 includes a housing 60, a cooler 70 and a circuit board 80 arranged in parallel at intervals inside the housing 60, and switching elements 20a to 20d. It is equipped with a PFC reactor 10.

The housing 60 is made of a heat-conducting material, and is made of, for example, a metal material such as aluminum. The cooler 70 is a heat dissipation base having a water channel.

The switching elements 20a to 20d (first circuit components) are located between the cooler 70 and the circuit board 80, and are arranged on the first surface 70a (the upper surface of the paper surface in FIG. 1) of the cooler 70 on the circuit board 80 side. ing. Further, the PFC reactor 10 (second circuit component) is arranged on the second surface 70b (the surface on the lower side of the paper in FIG. 1) on the back side of the first surface 70a of the cooler 70.

The circuit board 80 is, for example, a glass epoxy board, and has the above-mentioned wirings 1 to 4 for electrically connecting the switching elements 20a to 20d, the PFC reactor 10, the input power supply 30, and the smoothing capacitor 40, and the switching elements 20a to 20a. At least a part of the control unit that controls 20d is mounted, and constitutes a part of the bridgeless PFC circuit 50 shown in FIG.

The switching element is a wide band gap material such as (Gangallium Nitride), SiC (Silicon Carbide), or a diode for high power applications made of Si (Silicon), MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor). It is an element in which a bare chip such as an Integrated Gate Bipolar Transistor) is sealed with a plate-shaped semiconductor package.

In the following description, the switching element 20a will be described as an example, but the same applies to the other switching elements 20b to 20d. The switching element 20a has a cooling surface 20ac for heat dissipation, and is mounted via an insulating sheet (not shown) so that the cooling surface 20ac comes into contact with the first surface 70a of the cooler 70.

The terminal 20at of the switching element 20a extends toward the back side of the cooling surface 20ac and is connected to the circuit board 80. The PFC reactor 10 is a magnetic component formed of a winding and a magnetic material. The terminal 10t of the PFC reactor 10 is connected to the wiring 1 of the circuit board 80 through the through hole 70h of the cooler 70.

Next, the effect of the power conversion device 100 according to the first embodiment will be described.
As shown in FIG. 1, in the power conversion device 100, the switching element 20a is arranged on the first surface 70a of the cooler 70, and the PFC reactor is placed on the second surface 70b on the back side of the first surface 70a of the cooler 70. 10 is arranged, a through hole 70h is formed in the cooler 70, and the terminal 10t of the PFC reactor 10 is passed through the through hole 70h and connected to the circuit board 80.

Since the switching element 20a and the PFC reactor 10 having different heights in the normal direction X of the mounting surface are arranged on one surface of the flat plate cooler 70, respectively, the heights of the switching element 20a and the PFC reactor 10 are high. There is no need to match. Therefore, when the switching element 20a is connected to the circuit board 80, a step in the housing for height adjustment or a member for extending the terminal becomes unnecessary, and the cost thereof can be suppressed.

FIG. 3 is a cross-sectional view showing another configuration of the power conversion device 100. A cross section cut at a portion where the switching element 20a is present is shown. At least a part of the switching element 20a is arranged so as to overlap the PFC reactor 10 when viewed in the normal direction X of the first surface 70a or the second surface 70b of the cooler 70.

In this way, by arranging the switching element 20a and the PFC reactor 10 at overlapping positions on the front and back surfaces of the cooler 70, the surface areas of the first surface 70a and the second surface 70b of the cooler 70 are reduced, and the casing is made. The body 60 can be miniaturized.

FIG. 4 is a cross-sectional view showing another configuration of the power conversion device 100.
The through hole 70h is arranged so that at least a part thereof overlaps with the PFC reactor 10 when viewed in the normal direction X of the first surface 70a or the second surface 70b of the cooler 70.

As a result, the terminal length of the terminal 10t of the PFC reactor 10 can be shortened, so that the cost caused by the extension of the terminal length can be suppressed.

The circuit components arranged on the first surface 70a of the cooler 70 are not limited to the switching elements 20a to 20d, but like the switching elements 20a to 20d, the components whose component terminals are extended at high cost are arranged. It is preferable to do so. For example, the PFC reactor 10 having a large component height in the normal direction X and low cost for extending the component terminal is placed on the first surface 70a of the cooler 70, the component height is low, and the component terminal extension is high. A case where the costly switching element 20a is arranged on the second surface 70b of the cooler will be examined.

Since the terminal 20at of the switching element 20a arranged on the second surface 70b needs to be connected to the circuit board 80 on the first surface 70a side of the cooler 70 through the through hole 70h, the terminal length is at least It is the sum of the thickness of the cooler 70 in the normal direction X and the height of the PFC reactor 10. When this sum is larger than the terminal length of the terminal 20at of the switching element 20a, the switching element 20a cannot be connected to the circuit board 80.

In this case, there is a method in which a terminal extension member such as a bus bar is arranged between the switching element 20a and the circuit board 80, and the switching element 20a and the circuit board 80 are electrically connected via the terminal extension member. There is a problem that additional costs are incurred due to the addition of members.

There is also a method of changing the package shape of the switching element 20a, but the types of the package shape of the switching element are limited, and if the terminal length is insufficient in the ready-made package, the switching element can be customized by extending the terminal length. Since it is necessary to manufacture a product, there arises a problem that the manufacturing cost of the switching element increases.

On the other hand, with respect to the switching element 20a, in the case of extending the terminal length, the PFC reactor 10 only needs to extend the winding length forming the component, and the terminal is cheaper than manufacturing a custom product of the switching element. The length can be extended. Therefore, regardless of whether the cooler 70 is arranged on the first surface 70a or the second surface 70b, the cost due to the extension of the terminal length is almost the same.

As described above, arranging a component such as a switching element whose terminal extension is costly on the second surface 70b of the cooler 70 is more costly than arranging the component on the first surface 70a of the cooler 70. That is, by making the circuit parts arranged on the first surface 70a of the cooler 70 into parts such as switching elements 20a to 20d for which the extension of the component terminals is costly, the cost due to the addition of the terminal extension member or the extension of the terminal length is required. The increase can be suppressed.

In the present embodiment, the bridgeless PFC circuit 50 has been described as an example, but the present invention is not limited to this circuit and can be appropriately changed. For example, an isolated full-bridge DC / DC converter may be used.

Further, in the present embodiment, the magnetic component corresponding to the second circuit component has been described using the PFC reactor as an example, but the component is not limited to this component, and other components can be appropriately changed. The magnetic component refers to a winding component such as a reactor, a CMC (Common mode choke coil), or a transformer.

Although the present application describes exemplary embodiments, the various features, embodiments, and functions described in the embodiments are not limited to the application of a particular embodiment, either alone or. Various combinations are applicable to the embodiments.
Therefore, innumerable variations not exemplified are envisioned within the scope of the techniques disclosed in the present application. For example, it is assumed that at least one component is modified, added or omitted.

100 power converter, 1,2,3,4 wiring, 10 PFC reactor,
20 converter, 20a to 20d switching element, 10t, 20at terminal,
20ac cooling surface, 30 input power supply, 40 smoothing capacitor,
50 bridgeless PFC circuit, 60 housing, 70 cooler, 70a first side,
70b second surface, 70h through hole, 80 circuit board, Vdc DC voltage, X normal direction.

The power converter disclosed in the present application is
With the housing
The coolers and circuit boards arranged side by side inside the housing,
A semiconductor switching element arranged on the first surface of the cooler on the circuit board side,
It comprises a winding arranged on the second surface behind the first surface of the cooler and a magnetic component made of a magnetic material .
The terminal of the semiconductor switching element is connected to the circuit board and is connected to the circuit board.
The terminal of the winding of the magnetic component is connected to the circuit board through a through hole provided in the cooler.

Claims (5)

With the housing
The coolers and circuit boards arranged side by side inside the housing,
The first circuit component arranged on the first surface of the cooler on the circuit board side, and
A second circuit component arranged on a second surface behind the first surface of the cooler is provided.
The terminal of the first circuit component is connected to the circuit board and is connected to the circuit board.
The terminal of the second circuit component is a power conversion device connected to the circuit board through a through hole provided in the cooler. A claim in which at least a part of the first circuit component is arranged so as to overlap the second circuit component with the cooler interposed therebetween when viewed in the normal direction of the first surface or the second surface. Item 1. The power conversion device according to Item 1. The first or second aspect of the present invention, wherein at least a part of the through hole is arranged so as to overlap with the second circuit component when viewed in the normal direction of the first surface or the second surface. Power converter. The first circuit component is a semiconductor switching element.
The power conversion device according to any one of claims 1 to 3, wherein the second circuit component is a magnetic component. The power conversion device according to claim 4, wherein the second circuit component is a transformer, a reactor, or a CMC.

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