1. A power conversion apparatus comprising: a housing which is comprised of metallic plates; 5 a power conversion circuit which is enclosed in the housing; and a plurality of wiring conductors which are arranged inside the housing and connected to the power conversion circuit and through which an alternating current which is 10 a principal current flows. wherein the wiring conductors are laid close to one lateral side of the housing such that their longitudinal planes are parallel with the one lateral side of the housing, and 15 wherein the one lateral side of the housing is provided with a plurality of slits in positions facing with the wiring conductors and along a longitudinal direction of the wiring conductors. 20 2. The power conversion apparatus according to claim 1, wherein the width of each of the slits is wider than the width of each of the wiring conductors.

3. The power conversion apparatus according to 25 claim 1, wherein the longitudinal direction of the wiring 23 conductors is a height direction of the housing.

4. The power conversion apparatus according to claim 3, wherein the slits are provided only along the 5 height direction of the housing.

5. The power conversion apparatus according to claim 1, wherein the length of each of the slits is equal to the length of each of the wiring conductors in the 10 longitudinal direction.

6. The power conversion apparatus according to claim 1, wherein the slits are provided with a plurality of eaves, respectively. 15

7. The power conversion apparatus according to claim 6, wherein the eaves are set at an angle outward from the housing. 20 8. The power conversion apparatus according to claim 1, wherein the slits are covered with a non-magnetic object.

9. The power conversion apparatus according to 25 claim 1, wherein the metallic plates are steel plates. 24

10. The power conversion apparatus according to claim 1, wherein the power conversion circuit performs power conversion by controlling ON/OFF of semiconductor 5 switching elements and the wiring conductors are connected to alternating current terminals of the power conversion circuit.

11. The power conversion apparatus according to 10 claim 1, wherein the wiring conductors have a flat plate form and one lateral surface, in a through-thickness direction, of the flat plate form faces the one lateral side of the housing, and the through-thickness direction is a width direction of the wiring conductors. 15

12. The power conversion apparatus according to claim 11, wherein the wiring conductors are arranged alongside such that the flat surfaces of the conductors of the flat plate form face each other.

POWER CONVERSION APPARATUS
BACKGROUND OF THE INVENTION
Field of the Invention
5 The present invention relates to a power conversion
apparatus with a housing that encloses a power conversion
circuit.
Description of Prior Art
In natural energy power supply systems such as solar
10 photovoltaic power generation and wind power generation,
which are actively introduced in recent years, a power
conditioner which converts a direct current to an
alternating current and a frequency conversion apparatus
to prevent frequency from varying are used. And now, in
15 data centers for management of data collected over the
Internet and from mobile phones, an uninterruptible power
supply is used. Thus, the application field of power
conversion apparatus is expanding, including traditional
motor drives.
20 Introduction of natural energy power supply systems
and a spread of mobile phones are pursued in many
countries and regions, and demand for power conversion
apparatus is growing rapidly and globally. Along with the
growth of the demand, cost reduction is required and,
25 accordingly, downsizing power conversion apparatus is
3
pursued.
However, in consequence of downsizing, a magnetic
flux generated by a current flowing through wiring
conductors which are arranged in the close vicinity of the
inside 5 of the housing of a power conversion apparatus
generates an eddy current on the surface of the housing,
and the electrical resistance of the housing material
generates a loss by Joule heat, which poses a problem that
the housing becomes hot.
10 To address this problem, as related art to suppress
heat generation by an eddy current, technical approaches
described in Japanese Unexamined Patent Application
Publication No. Hei 5(1993)-300630 (Fig. 1) and Japanese
Unexamined Patent Application Publication No. Hei
15 11(1999)-345724 (Fig. 9) are known.
In a technical approach described in Japanese
Unexamined Patent Application Publication No. Hei 5(1993)-
300630 (Fig. 1), a frame that encloses bus conductors is
provided with slits extending along an axial direction of
20 the bus conductors and these slits are covered with a nonmagnetic
material. Because of large magnetic resistance
of the slit portions, a magnetic flux around the frame
decreases, an eddy current generated on the frame
decreases, and heat generation in the frame is suppressed.
25 In a technical approach described in Japanese
4
Unexamined Patent Application Publication No. Hei
11(1999)-345724 (Fig. 9), one of non-magnetic metallic
plates forming a box surrounding a high-frequency
transformer is provided with slits to prevent generation
5 of an eddy current and prevent temperature rise of the
non-magnetic metallic plates.
In the related art mentioned above, a geometric
relation between wiring conductors or an electric device
generating a magnetic flux and the positions of the slits
10 has influence on eddy current magnitude and distribution.
Therefore, in the case of power conversion apparatus
enclosed in a large housing for a large amount of power,
there is a problem that slits, even if provided, fail to
sufficiently reduce temperature rise of the housing and
15 the housing becomes hot locally.
SUMMARY OF THE INVENTION
Therefore, the present invention provides a power
conversion apparatus in which temperature rise of its
20 housing due to an eddy current can be suppressed certainly.
To solve the abovementioned problems, a power
conversion apparatus according to the present invention
includes a housing which is comprised of metallic plates,
a power conversion circuit which is enclosed in the
25 housing, and plural wiring conductors which are arranged
5
inside the housing and connected to the power conversion
circuit and through which an alternating current which is
a principal current flows. The wiring conductors are laid
close to one lateral side of the housing such that their
5 longitudinal planes are parallel with the one lateral side
of the housing. The one lateral side of the housing is
provided with plural slits in positions facing with the
wiring conductors and along a longitudinal direction of
the wiring conductors.
10 According to the present invention, plural slits
provided in the housing along a longitudinal direction of
plural wiring conductors serve to decrease mutual
inductance between the wiring conductors and the housing.
It is thus possible to reduce an eddy current that is
15 generated on the housing due to a magnetic flux generated
by an alternating current flowing through the wiring
conductors. Thereby, it is possible to suppress
temperature rise of the housing due to an eddy current.
Problems, structures, and advantageous effects other
20 than those mentioned above will become apparent from the
following description of embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1A is a schematic diagram to explain generation
25 of an eddy current;
6
Fig. 1B denotes an equivalent circuit when an eddy
current is generated on the housing;
Fig. 2A is a perspective view of an internal
structure of a power conversion apparatus which is a first
5 embodiment;
Fig. 2B depicts a planar view of a lateral surface
of the housing, the inside of the lateral surface facing
with wiring, in the first embodiment;
Fig. 3 depicts one example of a power conversion
10 circuit in a power conversion unit;
Fig. 4 represents a relationship between a ratio
between a slit width and a wiring line width and mutual
inductance;
Fig. 5A is a perspective view of an internal
15 structure of a power conversion apparatus which is a
second embodiment;
Fig. 5B depicts a side view of the housing when
viewed from a direction in which the wiring conductors are
arranged alongside in the second embodiment; and
20 Fig. 6 is an external perspective view depicting an
outlined structure of a power conversion apparatus which
is a third embodiment.
DETAILED DESCRIPTION OF THE INVENTION
25 In the following, embodiments of the present
7
invention will be described by way of the drawings. In
the drawings, constituent elements marked with the same
reference numeral are those that are identical or that
have a similar function.
5 To begin with, a description is provided of a
mechanism in which the surface temperature of the housing
of a power conversion apparatus rises.
Fig. 1A is a schematic diagram to explain generation
of an eddy current. When an alternating current i (e.g.,
10 50 Hz or 60 Hz AC) flows through a wiring conductor 2 that
is laid close to a housing 1, a magnetic flux  is
generated and this magnetic flux generates an eddy current
on the surface of the housing 1.
Fig. 1B denotes an equivalent circuit when an eddy
15 current has been generated on the housing 1. The wiring
conductor 2 and the housing 1 are equivalently represented
by an air core transformer 5. When the alternating
current i flows through the wiring conductor 2, a voltage
Ve which is expressed by Equation (1) is generated on the
20 surface of the housing 1.
Ve = M  (di/dt) ... (1)
where M is mutual inductance of the air core
transformer 5 and di/dt is the time rate of change of the
current.
25 Furthermore, given that Rs denotes electrical
8
resistance 7 of an eddy current path, a loss by Joule heat
J which is generated by the eddy current is expressed by
Equation (2).
J = Ve
2/Rs = (M  di/dt)2/Rs ... (2)
5 Since temperature rise of the housing 1 is
proportional to the loss by Joule heat J, temperature rise
of the housing 1 is proportional to a square of the mutual
inductance (M) of the air core transformer 5 and inversely
proportional to the electrical resistance (Rs) of the eddy
10 current path, according to Equation (2). di/dt depends on
the circuit characteristics of the power conversion
apparatus. Therefore, in order to suppress temperature
rise depending on how the housing 1 and the wiring
conductor 2 are configured, the mutual inductance (M)
15 between the wiring conductor 2 and the housing 1 is
decreased or the electrical resistance (Rs) of the eddy
current path in the housing 1 is increased.
Then, descriptions are provided about an embodiment
of the present invention which takes the above-described
20 mechanism of eddy current generation into consideration.
First Embodiment
Fig. 2A and Fig. 2B depict an outlined structure of
a power conversion apparatus which is a first embodiment
25 of the present invention. Fig. 2A is a perspective view
9
of an internal structure and Fig. 2B depicts a planar view
of a lateral surface of the housing with the inside of the
lateral surface facing with wiring.
In the first embodiment, a power conversion unit 20
which 5 handles three-phase alternating current power is
enclosed in the housing 1. A wiring conductor 2a for
phase U, a wiring conductor 2b for phase V, and a wiring
conductor 2c for phase W are connected to the power
conversion unit 20 inside the housing 1. Thus, an output
10 current of the power conversion unit 20, namely, a threephase
alternating current which is a principal current,
flows through the wiring conductors 2a, 2b, and 2c. The
housing 1 is comprised of steel plates which are
relatively inexpensive as a metallic plate material. The
15 power conversion unit 20 handles a large amount of power
(e.g., several MVA or more). The frequency of the output
current of the power conversion unit 20 is relatively low
(e.g., on the order of several 10 to several 100 Hz at a
maximum). One example of a power conversion circuit in
20 the power conversion unit 20 is depicted in Fig. 3.
The power conversion circuit in Fig. 3 converts
direct current power to three-phase alternating current
power or converts three-phase alternating current power to
direct current power by controlling ON/OFF of
25 semiconductor switching elements 101 to 106 (insulated
10
gate bipolar transistors (IGBTs) in Fig. 3). This power
conversion circuit includes an upper arm in which a
semiconductor switching element 101 and a diode 201 are
connected inverse parallel and a lower arm in which a
semiconductor switching element 102 and a diode 202 5 are
connected in inverse parallel. Both ends of a circuit in
which the upper arm and lower arm are connected in series
are connected to direct current terminals P and N (P is a
high potential terminal and N is a low potential terminal)
10 and a point of connection between the upper and lower arms
is connected to an alternating current terminal U for
phase U. Further, both ends of a circuit in which an
upper arm comprised of a semiconductor switching element
103 and a diode 203 and a lower arm comprised of a
15 semiconductor switching element 104 and a diode 204 are
connected in series are connected to the direct current
terminals P and N, respectively, and a point of connection
between the upper and lower arms is connected to an
alternating current terminal V for phase V. Furthermore,
20 both ends of a circuit in which an upper arm comprised of
a semiconductor switching element 105 and a diode 205 and
a lower arm comprised of a semiconductor switching element
106 and a diode 206 are connected in series are connected
to the direct current terminals P and N, respectively, and
25 a point of connection between the upper and lower arms is
11
connected to an alternating current terminal W for phase W.
That is, this power conversion circuit includes three
circuits in each of which the upper and lower arms are
connected in series according to the number of alternating
current phases. 5 And now, although one semiconductor
switching element and one diode are depicted to form one
arm, plural semiconductor switching elements may be
connected in parallel and plural diodes may be connected
in parallel in proportion to power capacity. Further, one
10 arm, for example, an upper arm for phase U which is
comprised of a semiconductor switching element 101 and a
diode 201 may be configured by a power semiconductor
module PM.
The wiring conductors 2a, 2b, and 2c depicted in
15 Figs. 2A and 2B are connected to the alternating current
terminals U, V, and W, respectively, in Fig. 3.
These wiring conductors 2a, 2b, and 2c are made from
flat plate-form bus bars made of a metallic conductor such
as a copper material 2a，2b， 2c to allow a larger current
20 to flow through them. The wiring conductors 2a, 2b, and
2c are laid close to one lateral side of the housing 1
such that their longitudinal planes are parallel with the
one lateral side of the housing 1 inside the housing 1.
Moreover, in the first embodiment, the wiring conductors
25 2a, 2b, and 2c are arranged along a height direction of
12
the housing 1 and arranged such that one lateral surface,
in a through-thickness direction, of the flat plate-form
conductors faces, in the close vicinity of, the one
lateral side of the housing 1. In addition, inside the
5 housing 1, the wiring conductors 2a, 2b, and 2c are
arranged alongside in substantially evenly spaced
positions such that the flat surfaces of the conductors of
the flat plate form parallelly face each other. The upper
ends of the wiring conductors 2a, 2b, and 2c are
10 positioned at a substantially same height for connection
to the power conversion unit 20 located in a top region
inside the housing 1. The lower ends of the wiring
conductors 2a, 2b, and 2c are positioned at different
levels for connection to another circuit section by
15 bending the conductor at right angle and extending it; the
lower end position of the wiring conductor 2c is lowest
and the lower end position of the wiring conductor 2b is
lower than that of the wiring conductor 2a. In this
arrangement of the wiring conductors 2a, 2b, and 2c, the
20 flat surfaces of the flat-plate wiring conductors 2a, 2b,
and 2c extending in the height direction of the housing
overlap with each other. Therefore, it is possible to
reduce a space where the wiring conductors 2a, 2b, and 2c
are installed in conjunction with means for reducing an
25 eddy current which will be described later and it is
13
possible to reduce the dimensions of the housing 1, in
other words, the dimensions of the power conversion
apparatus.
In the first embodiment, furthermore, as depicted in
5 Fig. 2A, one lateral side of the housing 1 is provided
with elongated slits 10 in positions facing with one
lateral surface, in a through-thickness direction, of each
of the flat plate-form wiring conductors 2a, 2b, and 2c;
the elongated slits 10 define opening portions on the one
10 lateral side of the housing 1. The lengths of the slits
10 which respectively face with the wiring conductors 2a,
2b, and 2c have dimensions that are substantially equal to
the lengths of the wiring conductors 2a, 2b, and 2c in the
height direction of the housing, in order words, in their
15 longitudinal direction and equal to at least the lengths
of the conductors except for their portions for connection
to the power conversion unit 20. Further, as depicted in
Fig. 2B, in the appearance of the one lateral side of the
housing 1, the widths (corresponding to W in Fig. 4), in a
20 through-thickness direction, of the wiring conductors 2a,
2b, and 2c are smaller than the widths (corresponding to
Ws in Fig. 4) of the slits 10 in a direction perpendicular
to their longitudinal direction. Therefore, the
substantially whole of each of the wiring conductors 2a,
25 2b, and 2c in the height direction of the housing is
14
positioned within each of the slits 10.
These slits 10 serve to reduce a magnetic flux that
is generated by the three-phase alternating current
flowing through the wiring conductors 2a, 2b, and 2c and
5 interlinked with one lateral side of the housing, the
lateral side facing with the wiring conductors.
Consequently, the mutual inductance M between the wiring
conductors 2a, 2b, and 2c and the housing 1 is decreased.
Therefore, even if the wiring conductors are arranged in a
10 narrow space inside the housing 1 and the clearance
between the housing 1 and the wiring 2 is reduced in a
manner of arrangement and configuration of the wiring
conductors inside the housing, as described previously, it
is possible to suppress temperature rise of the surface of
15 the housing 1 due to an eddy current. Moreover, because
the mutual inductance M between the wiring conductors 2a,
2b, and 2c and the housing 1 is decreased by means of the
slits 10, it is possible to reduce an eddy current on the
surface of the housing 1, even if the housing is comprised
20 of steel plates that are of a magnetic material as in the
first embodiment.
And now, according to an examination made by the
present inventors, in an instance where wiring conductors
are laid with their longitudinal direction along the
25 height direction of the housing, as in the first
15
embodiment inside the housing, heat that is generated by
an eddy current generated by an alternating current
flowing through the wiring conductors is carried upward by
air and, thus, temperature in the vicinity of the upper
ends of the wiring conductors 2 goes up. 5 . Taking such a
phenomenon into consideration, in the first embodiment,
the slits are provided to extend along only the height
direction among the height and other directions of the
wiring conductors 2a, 2b, and 2c. Thereby, there is a
10 decrease in working man-hours for forming the slits 10 in
the housing 1 and, accordingly, the manufacturing cost of
the power conversion apparatus can be saved. Further, in
order to decrease the mutual inductance more effectively,
the widths of the slits should be wider than the widths,
15 in a through-thickness direction, of the wiring conductors
2a, 2b, and 2c, as depicted in Fig. 2B and as will be
described later; however, in the present embodiment,
elongated slits 10 are provided on one lateral side of the
housing 1, the lateral side facing with one lateral
20 surface, in a through-thickness direction, of each of the
flat plate-form wiring conductors 2a, 2b, and 2c. Thus,
an increase in the opening areas of the slits 10 is
suppressed. This can lead to suppressing dust getting
into the housing from the opening portions.
25 Fig. 4 represents a relationship between a ratio
16
between a slit width Ws and the width, in a throughthickness
direction, of a wiring conductor, i.e., wiring
line width and the mutual inductance between the wiring
conductors 2 and the housing 1, based on the examination
by 5 the present inventors. A value of the mutual
inductance is a relative value assuming that the mutual
inductance is 1 when the wiring line width W = 0.
In a range where Ws/W is at or below 1, that is, the
slit width Ws is equal to or smaller than the wiring line
10 width W, an effect of decreasing the mutual inductance is
so quite small that it cannot be indicated clearly in Fig.
4. But, in a range where Ws/W is more than 1, that is,
the slit width Ws is larger than the wiring line width W,
the mutual inductance decreases significantly. According
15 to an examination made by the present inventors, this is
because a major part of magnetic flux that is interlinked
with the housing within a magnetic flux generated by the
current flowing through the wiring conductors is generated
in the periphery of the wiring conductors, that is, in a
20 space out of the range of the width of each wiring
conductor. That is, on one lateral side of the housing,
the lateral side adjacently facing the wiring conductors,
opening portions whose area widens beyond the range of the
width W of each wiring conductor from within the range
25 should be provided, in other words, slits whose width Ws
17
(> W) is wider than the wiring line width W should be
provided, thereby enabling it to decrease an interlinkage
magnetic flux certainly. Accordingly, in the first
embodiment, in order to suppress temperature rise of the
5 housing due to an eddy current, it is preferable to make
the slit width Ws larger than the wiring line width W, as
depicted in Fig. 2B.
Second Embodiment
10 Fig. 5A and Fig. 5B depict an outlined structure of
a power conversion apparatus which is a second embodiment
of the present invention. Fig. 5A is a perspective view
of an internal structure and Fig. 5B depicts a side view
of the housing 1 when viewed from a direction in which the
15 wiring conductors 2a, 2b, and 2c are arranged alongside.
Descriptions are provided below about what differs from
the first embodiment.
In the second embodiment, the slits 10 facing with
the wiring conductors 2a, 2b, and 2c are each separated
20 into several ones along a height direction and separated
slits are provided with eaves 11, respectively. By
providing the eaves 11, it is possible to prevent foreign
matters such as dust from getting into the housing from
outside.
25 As depicted in Fig. 5A, there remains a portion 1a
18
of the housing between separated slit sections. As
depicted in Fig. 5B, one end of a thin plate material of
which an eave 11 is made is fixed onto the outside surface
of the portion 1a of the housing and the thin plate
5 material is bent and set at an angle outward from the
housing, in order words, toward a direction far from the
wiring conductors. Accordingly, even if the eaves 11 are
made of a steel plate material as with the housing,
practically no eddy current flows in the eaves 11 and the
10 effect of the slits 10 remains intact.
The eaves 11 may be of arbitrary material such as
metal and resin. Further, when forming the slits, on a
housing surface where the slits 10 should be formed, the
slits 10 and the eaves 11 may be formed at the same time
15 and the eaves may be configured integrally with the
housing surface, without solely creating slit holes in the
surface.
Third Embodiment
20 Fig. 6 depicts an outlined structure of a power
conversion apparatus which is a third embodiment of the
present invention. Fig. 6 is an external perspective view
when viewing a housing surface (lateral side) where the
slits 10 are provided from outside. Descriptions are
25 provided below about what differs from the first
19
embodiment.
In the third embodiment, on the outside of one
lateral side of the housing 1, where the slits 10 are
provided, covers 12 of a thin flat plate form, made of
5 non-magnetic metal (e.g., aluminum and stainless steel),
are provided to cover the slits 10.
A magnetic flux that is generated by the three-phase
alternating current flowing through the wiring conductors
2a, 2b, and 2c is also interlinked with the covers 12.
10 But, practically no eddy current is generated in the
covers 12 in the third embodiment because the magnetic
permeability of non-magnetic metal which is the material
of the covers 12 is lower than that of a steel plate
material of which the housing 1 is made. Accordingly,
15 temperature rise of the surface of the housing 1 is
suppressed. Moreover, because the slits 10 which define
opening portions on the lateral side of the housing are
covered by the covers 12, it is possible to prevent
foreign matters such as dust from getting into the housing
20 from outside.
The shape of the covers 12 is not limited to a flat
plate form and may be a foil form or sheet form. By
providing the covers of a flat plate form (with a
thickness on the order of 1 mm to several millimeters), as
25 in the present embodiment, the strength of the housing’s
20
lateral side where the slits 10 are provided can be
enhanced. If the covers 12 of a foil form or sheet form
are applied, the housing’s lateral side where the slits 10
are provided can be flattened, and the covers 12, even if
5 installed, practically does not augment the weight of the
power conversion apparatus.
The present invention is not limited to the
embodiments described hereinbefore and various
modifications are included therein. For example, the
10 foregoing embodiments are those described in detail to
explain the present invention clearly and the invention is
not necessarily limited to those including all components
described. For a subset of the components of each
embodiment, other components can be added to the subset or
15 the subset can be removed or replaced by other components.
For example, the material of the housing is not
limited to steel plates and may be other metallic
materials. For example, even if the housing is made of a
non-magnetic metal, an eddy current that is too large to
20 ignore may be generated if the frequency of the current is
high; in that case, the slits on a lateral side of the
housing can serve to suppress eddy current generation.
The covers 12 to cover the slits 10 in Fig. 6 may be
made using a mesh-form or grid-form member.
25 The number of phases of alternating current power
21
that the power conversion apparatus handles may be plural,
not limited to three phases. In this case, the number of
wiring conductors should be a plural number equivalent to
the number of alternating current phases.
5 Furthermore, the power conversion circuit is not
limited to the one depicted in Fig. 3; as this circuit, a
multi-level inverter circuit of three levels or more, a
serial multiple inverter circuit, etc. can be applied.
Further, the semiconductor switching element is not
10 limited to IGBT; as this element, a Gate Turn-Off
thyristor (GTO thyristor) and the like can be applied.
22
We Claim:
1. A power conversion apparatus comprising:
a housing which is comprised of metallic plates;
5 a power conversion circuit which is enclosed in the
housing; and
a plurality of wiring conductors which are arranged
inside the housing and connected to the power conversion
circuit and through which an alternating current which is
10 a principal current flows.
wherein the wiring conductors are laid close to one
lateral side of the housing such that their longitudinal
planes are parallel with the one lateral side of the
housing, and
15 wherein the one lateral side of the housing is
provided with a plurality of slits in positions facing
with the wiring conductors and along a longitudinal
direction of the wiring conductors.
20 2. The power conversion apparatus according to
claim 1, wherein the width of each of the slits is wider
than the width of each of the wiring conductors.
3. The power conversion apparatus according to
25 claim 1, wherein the longitudinal direction of the wiring
23
conductors is a height direction of the housing.
4. The power conversion apparatus according to
claim 3, wherein the slits are provided only along the
5 height direction of the housing.
5. The power conversion apparatus according to
claim 1, wherein the length of each of the slits is equal
to the length of each of the wiring conductors in the
10 longitudinal direction.
6. The power conversion apparatus according to
claim 1, wherein the slits are provided with a plurality
of eaves, respectively.
15
7. The power conversion apparatus according to
claim 6, wherein the eaves are set at an angle outward
from the housing.
20 8. The power conversion apparatus according to
claim 1, wherein the slits are covered with a non-magnetic
object.
9. The power conversion apparatus according to
25 claim 1, wherein the metallic plates are steel plates.
24
10. The power conversion apparatus according to
claim 1, wherein the power conversion circuit performs
power conversion by controlling ON/OFF of semiconductor
5 switching elements and the wiring conductors are connected
to alternating current terminals of the power conversion
circuit.
11. The power conversion apparatus according to
10 claim 1, wherein the wiring conductors have a flat plate
form and one lateral surface, in a through-thickness
direction, of the flat plate form faces the one lateral
side of the housing, and the through-thickness direction
is a width direction of the wiring conductors.
15
12. The power conversion apparatus according to
claim 11, wherein the wiring conductors are arranged
alongside such that the flat surfaces of the conductors of
the flat plate form face each other.