JP6964217B2 - Power converter - Google Patents

Description

The present invention relates to a power conversion device for electric power input from a power generation device and a power storage device.

As awareness of environmental issues grows, interest in power generation methods that use natural energy is increasing. A typical example is a solar cell that converts light energy emitted from the sun into electrical energy. Solar cells have the advantages of being relatively compact, having a high degree of freedom in installation, and having high power generation efficiency. As a result, the number of homes with solar cells installed on the roof is increasing, coupled with the support of government policies. A solar cell installed in a house is an electric load installed in the house or a commercial power system GRID (hereinafter, may be simply referred to as "load, etc.").
The electric power generated from the solar cell is used as energy for private power generation or sales.

Further, in recent years, along with solar cells, residential power generation systems including storage batteries connected to the solar cells are increasing. In this type of residential power generation system, the electric power generated by the solar cell can be stored in the storage battery. Like the solar cell, the storage battery is electrically connected to the load in the house. The electric power stored in the storage battery is discharged at night or during a power outage and supplied to a load or the like.

However, since the electric power supplied from the solar cell or the storage battery is direct current, it cannot be supplied to the load or the like as it is. Therefore, for example, in a residential power generation system, a power conversion device called a so-called power conditioner is interposed between a solar cell or a storage battery and a load or the like. The power conversion device has a function of boosting (or stepping down) the input DC power to a predetermined voltage value and converting it into AC power. As a result, the DC power from the solar cell or the storage battery is converted into AC power that can be supplied to the load. As such a power conversion device, technologies such as Patent Documents 1 and 2 are disclosed.

Japanese Unexamined Patent Publication No. 2017-28882 Japanese Unexamined Patent Publication No. 2016-165218

In many of the above-mentioned types of power conversion devices, for example, an inverter circuit unit that converts DC power from a solar cell into AC power and a converter circuit unit that charges and discharges a storage battery are housed in separate housings. .. However, in the case of such a configuration, for example, the installation space for at least two housings is required on the outer wall W of the building to which the power conversion device is attached. In addition to that, since the two housings must be separately attached to the outer wall W of the building, the installation work time and work process will increase accordingly. Further, the wiring arranged between the housings (the wiring that electrically connects the inverter circuit portion in one housing and the converter circuit portion in the other housing) is exposed to the outside. Therefore, if the wiring is left as it is, the wiring may be directly exposed to rainwater, or some object may collide with the wiring. To prevent this, the entire externally exposed area of the wiring is covered with a plastic protective member. Measures are taken. However, in that case, since the protective member must be prepared and attached separately, there may be a problem that the cost and the work cost increase.

In view of the above problems, an object of the present invention is to provide a power conversion device capable of reducing the installation space on, for example, the outer wall W of a building and reducing the work time and work process required for installation. Another object of the present invention is to provide a power conversion device capable of reducing the wiring exposed to the outside of the housing. In the following, devices having a power generation function such as a solar cell may be collectively referred to as a "power generation device", and devices having a power storage function such as a storage battery may be collectively referred to as a "power storage device".

Inverter circuit section connected to power generator
The converter circuit section connected to the power storage device and
Wiring connecting the inverter circuit section and the converter circuit section,
Including the inverter circuit unit, the converter circuit unit, and a housing for accommodating the wiring.
The inverter circuit unit and the converter circuit unit are housed in the housing so as to be arranged side by side in a predetermined direction .
The inverter circuit unit and the converter circuit unit are arranged side by side in the depth direction of the housing.
,
The housing includes a peripheral wall portion and an upper lid portion, and includes a peripheral wall portion and an upper lid portion.
Further, the upper cover is attached to the peripheral wall portion so as to slide in the depth direction of the housing, characterized in Rukoto.

Further, the power conversion device according to the present invention is
It is preferable that the inverter circuit unit and the converter circuit unit are arranged side by side in the depth direction of the housing or in the width direction of the housing.

Further, the power conversion device according to the present invention is
When the inverter circuit unit and the converter circuit unit are arranged side by side in the depth direction of the housing,
The housing includes a peripheral wall portion and an upper lid portion, and includes a peripheral wall portion and an upper lid portion.
Further, it is preferable that the upper lid portion is attached to the peripheral wall portion so as to slide and move in the depth direction of the housing.

Further, the power conversion device according to the present invention is
When the inverter circuit unit and the converter circuit unit are arranged side by side in the depth direction of the housing,
The upper lid is
Including a front portion and a side portion extending from the front portion toward the back side and arranged so as to face the peripheral wall portion.
The side surface portion is attached to the peripheral wall portion,
The side surface portion preferably includes at least one through hole.

According to the present invention, it is possible to provide a power conversion device capable of reducing the installation space on, for example, the outer wall W of a building and reducing the installation work time and work process. Further, according to the present invention, it is possible to provide a power conversion device capable of reducing the wiring exposed to the outside of the housing.

The front perspective view of the power conversion apparatus which concerns on embodiment of this invention. An exploded perspective view of a lid provided in the power conversion device according to the embodiment of the present invention. The wiring system schematic diagram of the power conversion apparatus which concerns on embodiment of this invention. FIG. 6 is a schematic diagram of the internal configuration of the power conversion device according to the embodiment of the present invention. The schematic diagram which shows the operation of the housing provided in the power conversion apparatus which concerns on embodiment of this invention.

Hereinafter, as one of the embodiments of the present invention, power for converting DC power from a power generation device made of a solar cell or the like and DC power from a power storage device made of a lithium battery or the like into predetermined AC power synchronized with a commercial power system. An embodiment of the conversion device will be described with reference to the drawings.

First, the configuration outline of the power conversion device 1 according to the embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a front perspective view of the power conversion device 1 according to the present embodiment. Further, FIG. 2 is an exploded perspective view of the housing 2 provided in the power conversion device 1.

The power conversion device 1 according to the present embodiment is a housing 2 having a hollow inside and a substantially rectangular parallelepiped box shape.
To be equipped. In the housing 2, the inverter circuit unit 11 connected to the power generation device, the converter circuit unit 12 connected to the power storage device, and the wiring 13 electrically connecting the inverter circuit unit 11 and the converter circuit unit 12 are provided. included. The output side of the inverter circuit unit 11 is connected to a load or the like (commercial power system GRID). That is, the AC power converted by the inverter circuit unit 11 is supplied to the load or the like.

In this embodiment, the electric components (circuit elements) included in the inverter circuit unit 11 and the converter circuit unit 12 are provided on the mounting substrate. The mounting board is the housing 2 described later.
It is housed inside. However, the method of accommodating the inverter circuit unit 11 and the converter circuit unit 12 in the housing 2 is not limited to this.

As shown in FIGS. 1 and 2, the housing 2 in the present embodiment is connected to the ground potential and includes a peripheral wall portion 21, an upper lid portion 22, and a bottom plate portion 23 (not shown). Here, in the present embodiment, the peripheral wall portion 21, the upper lid portion 22, and the bottom plate portion 23 are made of colored steel plates whose one surface is color-painted. Here, a mounting board or the like on which electrical components are mounted is attached to the bottom plate portion 23.

The upper lid portion 22 includes a front portion (top plate) 221 and a side surface portion 222 extending from, for example, a peripheral portion of the front portion to the back side. The side surface portion 222 includes an upper side surface 222A, a lower side surface 222B, and a left side surface 2
It is composed of 22C and 222D on the right side. The back side of the upper lid portion 22 is open. This will
The upper lid portion 22 has a box shape having a hollow inside and a substantially rectangular parallelepiped shape.

As will be described later, the upper lid portion 22 in the present embodiment is attached to the side surface portion 222 in a state where it can be slidably moved in the depth direction of the housing 2. The structure of the slide mechanism and the like is arbitrary, but in the present embodiment, a protrusion extending substantially vertically from each inner surface of, for example, the left side surface 222C and the right side surface 222D of the upper lid portion 22 is provided, and the peripheral wall portion 21 is provided. Predetermined position (position of the peripheral wall portion 21 facing the protrusion when the upper lid portion 22 shown in FIG. 1 covers and overlaps the peripheral wall portion 21: FIG. 1
And in FIG. 2, two through holes 211 into which protrusions can be inserted are provided on both sides of the peripheral wall portion 21). The through hole 211 is formed in an elongated shape along the depth direction, and the through hole 2 is formed.
The protrusion inserted into 11 can be moved to the front side and the back side in the depth direction in a form guided by the through hole 211. The upper lid portion 22 provided with the protrusion also slides in the depth direction accordingly.

By providing the upper lid portion 22 that can slide and move in the depth direction of the housing 2, the internal space inside the housing 2 can be expanded in the depth direction. For example, when only the inverter circuit unit 11 is arranged in the housing 2 first and the converter circuit unit 12 is not initially arranged in the housing 2 (when the converter circuit unit 12 is retrofitted), the initial position. If the upper lid portion 22 is arranged on the back side in the depth direction, the depth dimension of the housing 2 can be shortened accordingly. On the other hand, if the upper lid portion 22 is slid toward the front side in the depth direction at the stage of retrofitting the converter circuit portion 12, a sufficient area for arranging the converter circuit portion 12 in the housing 2 can be secured. Can be done.

However, even if the upper lid portion 22 is not slid and moved, the slide mechanism may not be provided if a space capable of accommodating the converter circuit portion 12 is already secured in the housing 2. In that case, the housing 2 does not have to be separated from the peripheral wall portion 21 and the upper lid portion 22 as shown in FIG. That is, it may be configured to include one box-shaped member having a back opening (a housing composed of a peripheral wall portion and a front portion (top plate) that closes the front side opening region of the peripheral wall portion).

As shown in FIG. 2, the power conversion device 1 in the present embodiment further includes a heat sink portion (not shown), a back cover portion 3, and a mounting plate 4. The heat sink portion is arranged on the back side of the bottom plate portion 23 of the housing 2. That is, the heat sink portion is arranged so as to face the inverter circuit portion 11 and the converter circuit portion 12 with the bottom plate portion 23 interposed therebetween. By disposing the heat sink portion, the heat generated by the operation of the inverter circuit portion 11 and the converter circuit portion 12 is dissipated. Further, the back cover portion 3 is provided so as to cover the periphery of the heat sink portion. The back cover portion 3 is provided so as to extend from the back side peripheral portion of the peripheral wall portion 21, for example, to the back side of the housing 2. Further, the mounting plate 4 is provided to mount the power conversion device 1 on the outer wall W of the building. In the present embodiment, the mounting plate 4 is mounted and supported on the dorsal peripheral edge of the back cover portion 3 so as to be substantially parallel to the bottom plate portion 23.

Next, the circuit configuration included in the power conversion device 1 according to the present embodiment will be described with reference to FIG. FIG. 3 is a schematic diagram of the wiring system of the power conversion device 1 according to the present embodiment. Specifically, it is a schematic diagram of the single-phase two-wire type power conversion circuit 100 when the solar cell PV is one system in the power conversion device 1 when the solar cell PV is adopted as the power generation device.

The solar cell PV is connected to the first bus 120 via the first wiring 110 and the switch SW. The first noise filter circuit NF1 and the booster circuit BS are interposed in the first bus 120, and the DC power generated by the solar cell PV is supplied to the booster circuit BS. The booster circuit BS is composed of a chopper circuit including a DC reactor DCL, a switching element S1, a diode DD, and a capacitor CD, and turns the switching element S1 ON / OF at a predetermined frequency.
By F, the voltage of the input DC power is boosted to a predetermined voltage. The power boosted by the booster circuit BS is output to the inverter circuit unit 11 via the first bus 120. The first bus 120 is a bus in which a booster circuit BS is interposed and is responsible for connecting the solar cell PV and the inverter circuit unit 11.

On the other hand, the power storage device ES includes the second wiring 130 and the converter circuit unit (DC) described above.
/ DC converter) 12 is connected to the second bus 140. The converter circuit unit 12 mainly plays a role of adjusting the charge / discharge of the power storage device ES. The second bus 140 is the first bus 12
The DC power that is also connected to 0 and is output from the power storage device ES via the second bus 140 is the first
It is possible to supply the DC power to the bus 120 or to supply the DC power of the first bus 120 to the power storage device ES. Part of the second bus 140 (inverter circuit section 11 and converter circuit section 12)
The connection portion) is the wiring 13. A second noise filter circuit NF2 for attenuating the electric noise of the DC power supplied from the converter circuit unit 12 is arranged in the second bus 140, and the DC power discharged from the power storage device ES is noise. After passing through the filter circuit NF2, it is supplied to the inverter circuit unit 11.

The inverter circuit unit 11 is a circuit in which a plurality of switching elements S2 are fully bridged. These switching elements S2 are periodically turned ON / OFF by PWM control. As a result, the DC power of the first bus 120 is converted into pseudo sine wave AC power synchronized with the frequency of the commercial power system GRID. This converted AC power is the AC reactor ACL.
The high frequency component is attenuated by the filter circuit NF3 composed of the capacitor CA and formed into a sinusoidal shape. The AC power with the high frequency component attenuated is superimposed on the commercial power system GRID via the relay contact RY.

The control circuit PC is composed of a microcomputer or the like, and controls the ON / OFF operation of the switching element S1 of the booster circuit BS and the switching element S2 of the inverter circuit unit 11. Further, a switching circuit for switching DC supply such as a solar cell PV or a power storage device ES is appropriately provided.

Although FIG. 3 shows an example in which one solar cell is connected to the power conversion circuit 100, the number of solar cells connected to the power conversion circuit 100 is not limited to this. For example, PV2, P
N solar cells of V3, PV4 ... PVn may be connected to the inverter circuit unit 11 so as to be parallel to the above-mentioned solar cell PV1.

The electric load in the building is a mechanism that operates by either the commercial power system GRID or the power generated by the power conversion device 1, and the details thereof are omitted. The operation of the booster circuit BS, the DC / AC conversion circuit DA, and the relay contact RY is controlled by the control circuit PC. In the above wiring system, when the commercial power system GRID is a single-phase three-wire system (UOW),
This can be achieved by adopting a single-phase three-wire system (UOW) for the circuits after the DC / AC conversion circuit DA.

Next, with reference to FIG. 4, the state inside the housing 2 accommodating the inverter circuit unit 11 and the converter circuit unit 12 will be described. Here, FIG. 4A shows a mode in which the inverter circuit unit 11 and the converter circuit unit 12 are arranged side by side in the housing 2 in the housing 2. The upper view of FIG. 4A is a side sectional view of the power conversion device 1 according to the present embodiment, and is a side sectional view of FIG. 4A.
) Is a front view in a state where the upper lid portion 22 of the power conversion device 1 is removed. again,
In FIG. 4B, the inverter circuit unit 11 and the converter circuit unit 12 are formed in the housing 2.
An aspect in which they are arranged side by side in the width direction of the housing is shown. The upper view of FIG. 4B is a side sectional view of the power conversion device 1 according to the present embodiment, and the lower view of FIG. 4B is the upper lid portion 22 of the power conversion device 1.
It is a front view in a state where is removed.

First, the power conversion device 1 in which the circuit units are arranged side by side in the depth direction, as shown in FIG. 4A, will be described. The inverter circuit unit 11 is arranged on the back side of the housing 2 in the depth direction with respect to the converter circuit unit 12. The inverter circuit portion 11 is arranged on the bottom plate portion 23 of the housing 2 in a state of being mounted on the printed circuit board. The mounting board for the inverter circuit portion is preferably supported on the bottom plate portion 23 by a member such as a boss.

Further, the bottom plate portion 23 is provided with at least one (preferably a plurality) through holes. The wiring L1 connecting the inverter circuit unit 11 and the power system GRID is passed through the through hole. The wiring L1 connects the inverter circuit unit 11 and the power system GRID via the connector 161. Further, the wiring L2 connecting the inverter circuit unit 11 and the solar cell PV is passed through, for example, a through hole provided separately from the through hole described above. The wiring L2 connects the inverter circuit unit 11 and the solar cell PV via the connector 162.

The converter circuit unit 12 is arranged on the front side of the housing 2 in the depth direction with respect to the inverter circuit unit 11. The converter circuit unit 12 is arranged on, for example, an intermediate plate 24 provided immediately in front of the inverter circuit unit 11. The converter circuit unit 12 in this embodiment is provided on the intermediate plate 24 in a state of being mounted on the printed circuit board. The mounting board for the converter circuit section is preferably supported on the intermediate plate 24 by a member such as a boss.

The intermediate plate 24 includes at least one (preferably a plurality) through holes. The wiring 13 connecting the inverter circuit unit 11 and the converter circuit unit 12 is passed through the through hole. Wiring 1
Reference numeral 3 is a connection between the inverter circuit unit 11 and the converter circuit unit 12 via the connector 160. Further, the wiring L3 connecting the converter circuit unit 12 and the power storage device ES is passed through, for example, a through hole different from the through hole described above. The wiring L3 connects the converter circuit unit 12 and the power storage device ES via the connector 163.

Next, the power conversion device 1 in which the circuit units are arranged side by side in the width direction, as shown in FIG. 4B, will be described. The inverter circuit unit 11 is arranged on the left side in the width direction of the housing 2 with respect to the converter circuit unit 12. On the other hand, the converter circuit unit 12 is arranged on the right side in the width direction of the housing 2 with respect to the inverter circuit unit 11. However, the inverter circuit unit 11 and the converter circuit unit 1
The left-right positional relationship of 2 is not limited to this. When the inverter circuit unit 11 is arranged on the right side in the width direction, the converter circuit unit 12 is arranged on the left side in the width direction. Inverter circuit unit 11
And the converter circuit unit 12 are connected by a wiring 13 housed in the housing 2. Wiring 1
Reference numeral 3 is a connection between the inverter circuit unit 11 and the converter circuit unit 12 via the connector 160.

The bottom plate portion 23 in which the inverter circuit portion 11 and the converter circuit portion 12 are arranged is provided with at least one (preferably a plurality) through holes. Inverter circuit unit 11 and power system GRID
Wiring L1 (not shown) connecting the above, wiring L2 (not shown) connecting the inverter circuit unit 11 and the solar cell PV (not shown), wiring L3 connecting the converter circuit unit 12 and the power storage device ES, etc. , Passed through the through hole. When a plurality of through holes are provided, for example, one wiring may be passed through each through hole.

In FIGS. 4A and 4B, a state in which the converter circuit unit 12 is housed in the housing 2 in advance is shown. However, as described above, the converter circuit unit 12 may be retrofitted in the power conversion device 1 (inside the housing 2) that is already in use.

Next, the sliding movement of the housing 2 (upper lid portion 22) in the present embodiment will be described with reference to FIG. Here, FIG. 5A is a side view of the power conversion device 1 before the upper lid portion 22 of the housing 2 slides and moves. Further, FIG. 5B is a side view of the power conversion device 1 after the upper lid portion 22 of the housing 2 has been slid and moved.

As shown in FIG. 5A, the upper lid portion 22 before the slide movement is arranged so as to cover and overlap the peripheral wall portion 21. For example, when the converter circuit unit 12 is retrofitted, the upper lid portion 22 is arranged in this way as an initial state because it is not necessary to provide a storage space for the converter circuit unit 12 in the housing 2.

On the other hand, as shown in FIG. 5B, the upper lid portion 22 is manually slid to the front side in the depth direction, for example. The sliding movement of the upper lid portion 22 increases the internal space of the housing 2. As a result, an area for arranging the converter circuit unit 12 in parallel is secured in the area on the front side in the depth direction of the inverter circuit unit 11.

Here, the upper side surface 222A, the lower side surface 222B, the left side surface 222C, and the right side surface 22 of the upper lid portion 22
It is preferable to provide the through hole 223 in 2D. By providing such a through hole 223,
When the upper lid portion 22 slides toward the front side in the depth direction, the outer side and the inner side of the housing 2, which have been blocked by the peripheral wall portion 21, come into communication with each other. As a result, a new air flow path is formed in the housing 2. That is, for example, a heat dissipation path for heat generated by the operation of the converter circuit unit 12 is newly established. This makes it possible to dissipate the heat inside the housing 2 more efficiently.

1 ・ ・ ・ ・ ・ ・ ・ ・ Power converter 11 ・ ・ ・ ・ ・ ・ ・ Inverter circuit part 12 ・ ・ ・ ・ ・ ・ ・ ・ Converter circuit part 2 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・・ ・ Peripheral wall part 22 ・ ・ ・ ・ ・ ・ Top lid part 3 ・ ・ ・ ・ ・ ・ ・ ・ Back cover part 4 ・ ・ ・ ・ ・ ・ ・ ・ Mounting plate

Claims (2)

Inverter circuit section connected to power generator
The converter circuit section connected to the power storage device and
Wiring connecting the inverter circuit section and the converter circuit section,
Including the inverter circuit unit, the converter circuit unit, and a housing for accommodating the wiring.
The inverter circuit unit and the converter circuit unit are housed in the housing so as to be arranged side by side in a predetermined direction.
The inverter circuit unit and the converter circuit unit are arranged side by side in the depth direction of the housing.
The housing includes a peripheral wall portion and an upper lid portion, and includes a peripheral wall portion and an upper lid portion.
Further, the upper lid portion is a power conversion device that is mounted on the peripheral wall portion so as to slide and move in the depth direction of the housing. The upper lid is
Including a front portion and a side portion extending from the front portion toward the back side and arranged so as to face the peripheral wall portion.
The side surface portion is attached to the peripheral wall portion,
The power conversion device according to claim 1, wherein the side surface portion includes at least one through hole.

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