U.S. patent application number 09/918571 was filed with the patent office on 2002-05-02 for power supply apparatus.
Invention is credited to Horiuchi, Tatsuhito, Oda, Takashi.
Application Number | 20020051340 09/918571 |
Document ID | / |
Family ID | 18727719 |
Filed Date | 2002-05-02 |
United States Patent
Application |
20020051340 |
Kind Code |
A1 |
Oda, Takashi ; et
al. |
May 2, 2002 |
Power supply apparatus
Abstract
The power supply apparatus has a plurality of power modules, a
holder-case housing a parallel arrangement of power modules in a
plurality of rows and columns, and a fan. The interior of the
holder-case is divided into a plurality of partitions by walls.
Wall surfaces follow the contours of power module surfaces to
establish cooling ducts of uniform width. The holder-case has flow
inlets opened through the first surface plate and exhaust outlets
opened through the second surface plate. The power supply apparatus
uses the fan to divide and induce air flow through flow inlets into
a plurality of partitions, and expels air which has passed through
cooling ducts out the exhaust outlets thereby cooling power modules
disposed inside the partitions.
Inventors: |
Oda, Takashi; (Kato-gun,
JP) ; Horiuchi, Tatsuhito; (Kakogawa-city,
JP) |
Correspondence
Address: |
WENDEROTH, LIND & PONACK, L.L.P.
2033 K STREET N. W.
SUITE 800
WASHINGTON
DC
20006-1021
US
|
Family ID: |
18727719 |
Appl. No.: |
09/918571 |
Filed: |
August 1, 2001 |
Current U.S.
Class: |
361/695 ;
174/137R; 903/903; 903/907 |
Current CPC
Class: |
B60L 3/0046 20130101;
H01M 50/271 20210101; H01M 10/6566 20150401; B60K 6/28 20130101;
Y02T 10/70 20130101; Y10S 903/907 20130101; Y02T 10/72 20130101;
H01M 10/643 20150401; B60L 1/003 20130101; H01G 11/78 20130101;
B60L 58/26 20190201; Y02E 60/10 20130101; B60L 2240/545 20130101;
B60L 58/21 20190201; H01G 11/18 20130101; B60K 1/04 20130101; H01M
10/625 20150401; H01M 50/213 20210101; Y02E 60/13 20130101; Y10S
903/903 20130101; B60L 50/64 20190201; H01G 9/155 20130101; H01M
10/6556 20150401; B60K 2001/005 20130101; B60L 50/40 20190201; H01G
11/10 20130101; H01M 50/107 20210101; H01M 50/20 20210101; Y02T
90/16 20130101; H01M 10/613 20150401; H01M 50/291 20210101; B60L
2240/662 20130101; H01M 10/6563 20150401 |
Class at
Publication: |
361/695 ;
174/137.00R |
International
Class: |
H05K 007/20; H01B
017/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 3, 2000 |
JP |
235526/2000 |
Claims
What is claimed is:
1. A power supply apparatus comprising: (a) a plurality of power
modules; (b) a holder-case which houses power modules arranged in a
parallel fashion in a plurality of columns, and which cools the
power modules with air passing through its interior; (c) a fan
which forcibly supplies air to, or exhausts air from, the
holder-case; and wherein (d) the holder-case is a box shape and has
a first surface plate and a second surface plate as opposite
surfaces, and a plurality of power modules are arranged laterally
along the first surface plate and the second surface plate in a
plurality of columns; (e) the holder-case is provided with walls
between the plurality of power modules housed in a lateral
arrangement with a plurality of columns, and between the first
surface plate and the second surface plate, the walls extend from
the first surface plate to the second surface plate, the interior
is divided into a plurality of columns of partitions, and power
modules are disposed in each partition column; (f) surfaces of
walls which face power modules are shaped to follow the contours of
power module surfaces, cooling ducts of constant width are
established between power module surfaces and opposing wall
surfaces, and air directed into the partitions is made to flow
along power module surfaces via the cooling ducts; (g) flow inlets
are opened through the first surface plate of the holder-case to
divide air flow and induce air flow into the plurality of partition
column cooling ducts, and exhaust outlets are opened through the
second surface plate to expel air to the outside which has passed
through the plurality of partition column cooling ducts; and (h)
air flow is divided and induced to flow through first surface plate
flow inlets into a plurality of partition columns using a fan, air
is passed through cooling ducts to cool power modules, air which
has performed its cooling function is expelled from second surface
plate exhaust outlets, and power modules disposed in a plurality of
partition columns are cooled.
2. A power supply apparatus as recited in claim 1 wherein the power
modules are a plurality of rechargeable batteries connected in a
linear fashion.
3. A power supply apparatus as recited in claim 1 wherein the power
modules are a plurality of super capacitors connected in a linear
fashion.
4. A power supply apparatus as recited in claim 1 wherein the
holder-case is provided with upper and lower cover-casings and an
intermediate-casing disposed between the cover-casings, and the
cover-casings are provided with a first cover-casing formed as a
single piece with the first surface plate and a second cover-casing
formed as a single piece with the second surface plate.
5. A power supply apparatus as recited in claim 1 wherein wall
surfaces facing power modules are provided with retaining
projections, ends of the retaining projections contact power module
surfaces, and power modules are thereby held inside the
partitions.
6. A power supply apparatus as recited in claim 5 wherein the
retaining projections are provided extending in lateral directions
with respect to power module orientation.
7. A power supply apparatus as recited in claim 1 wherein cooling
duct width is approximately constant over the entire perimeter of a
power module.
8. A power supply apparatus as recited in claim 1 wherein power
modules and partitions are shaped as circular columns, power
modules are disposed at partition centers, and cooling ducts of
constant width are thereby established.
9. A power supply apparatus as recited in claim 1 wherein a
plurality of power modules are arranged in a parallel fashion in a
plurality of rows and a plurality of columns and housed in the
holder-case.
10. A power supply apparatus as recited in claim 1 wherein the
holder-case houses a plurality of power modules arranged in two
rows, and at least one dead air space is established in the
upstream partition of the first row disposed on the side of the
first surface plate.
11. A power supply apparatus as recited in claim 10 wherein cooling
ducts of the downstream partition are made nearly constant in width
over approximately the entire power module circumference, and the
width of cooling ducts of the upstream partition are made wider
than the width of cooling ducts of the downstream partition to
establish at least one dead air space.
12. A power supply apparatus as recited in claim 11 wherein cooling
ducts of the upstream partition are made nearly constant in width
over approximately half the power module circumference, in the
remaining half they are made wider to establish dead air
spaces.
13. A power supply apparatus as recited in claim 12 wherein dead
air spaces are established on the downstream side of the upstream
partition.
14. A power supply apparatus as recited in claim 11 wherein a
plurality of dead air spaces are established over approximately the
entire power module circumference in the upstream partitions.
15. A power supply apparatus as recited in claim 10 wherein the
upstream partition is square-shaped in a cross-section view, and a
dead air space is established in each part of its four corners.
16. A power supply apparatus as recited in claim 10 wherein the
width of cooling ducts between the upstream and downstream sides in
the upstream partitions is equal to the width of cooling ducts of
the downstream partition.
17. A power supply apparatus as recited in claim 10 wherein the
holder-case houses a plurality of power modules arranged in two
rows, and bypasses are established to direct air flow from upstream
partitions in the first row disposed on the side of the first
surface plate to downstream partitions in the second row disposed
on the side of the second surface plate.
18. A power supply apparatus as recited in claim 17 wherein the
bypasses extend in a tangential direction from both sides of a dead
air space to connect with a downstream partition.
19. A power supply apparatus as recited in claim 1 wherein the
holder-case houses a plurality of power modules arranged in a
plurality of rows, and the plurality of power modules of adjacent
rows are offset from vertical alignment.
20. A power supply apparatus as recited in claim 1 wherein slit
shaped flow inlets are opened through the first surface plate,
positioned at the center region of the partitions of the
holder-case, and slit shaped exhaust outlets are opened through the
second surface plate.
21. A power supply apparatus as recited in claim 1 wherein an air
inlet duct is provided at the surface of the first surface plate,
this inlet duct connects with a fan, and inlet duct cooling air
flow is divided among each flow inlet and introduced into each
partition.
22. A power supply apparatus as recited in claim 1 wherein an air
outlet duct is provided at the surface of the second surface plate,
this outlet duct connects with a fan, the fan forcibly intakes
cooling air from the outlet duct, and air flow expelled from each
partition converges and is exhausted to the outside.
23. A power supply apparatus as recited in claim 1 wherein an air
inlet duct is provided at the surface of the first surface plate,
an air outlet duct is provided at the surface of the second surface
plate, and a fan is connected to either or both the inlet duct and
the outlet duct to forcibly induce air flow.
Description
[0001] This application is based on application No. 235526 filed in
Japan on Aug. 3, 2000, the content of which incorporated hereinto
by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates to a high current power supply
apparatus primarily used to power a motor to drive a vehicle such
as a hybrid or electric car.
[0003] A high current, high output power supply apparatus used as a
power source for a motor to drive an automobile contains power
modules. Power modules are a plurality of series connected
batteries, and they are in turn connected in series to raise the
output voltage of the power supply apparatus. The purpose of this
is to increase the output of the driving motor. Extremely high
currents flow in a power supply apparatus used for this type of
application. For example, in a vehicle such as a hybrid car, when
starting to move or accelerating, battery output must accelerate
the car, and extremely high currents over 100A can flow. High
currents also flow during short period, rapid charging.
[0004] In a high current power supply apparatus, forced cooling is
required when battery temperature rises. In particular, in a power
supply apparatus with many power modules inserted in vertical and
horizontal columns and rows in a holder-case, it is important to
uniformly cool each power module. This is because performance
degradation will result for a battery which rises in temperature
when battery cooling is non-uniform.
[0005] Systems which house a plurality of power modules in a
holder-case and cool each power module more uniformly are cited,
for example, in Japanese Patent Applications HEI 10-270095 (1998)
and HEI 11-329518 (1999). As shown in the cross-section view of
FIG. 1, the power supply apparatus of the former application cools
internally housed power modules 121 by forcing air to flow from air
intakes 123 which form the base of the holder-case 122 to exhaust
outlets 124 which form the top of the holder-case 122. Cooling
adjustment fins 125 are disposed inside the holder-case 122 to
adjust the speed of air flowing over the surfaces of power modules
121.
[0006] In a holder-case 122 of this configuration, air flows more
rapidly over the surfaces of power modules 121 disposed near the
top than those near the bottom. The purpose of this is to avoid a
temperature differential between power modules 121 at the top and
bottom. If the flow rate of air passing over the surfaces of power
modules 121 at the top and bottom is made the same, power modules
121 at the bottom will be cooled more efficiently than those at the
top because air flowing over the surfaces of power modules 121 at
the bottom has a lower temperature.
[0007] To make the flow rate of air over power modules 121 at the
top faster than the flow rate over those at the bottom, the gap for
air flow between the cooling adjustment fins 125 and the power
modules 121 is gradually made narrower towards the top of the
holder-case 122. This is because air flow becomes faster as the gap
for air flow becomes narrower.
[0008] This type of power supply apparatus cools power modules near
the bottom with cool air and power modules near the top with high
flow rate air to establish a more uniformly cooled environment for
power modules at both the top and bottom. However, it is extremely
difficult to cool upper and lower power modules under very uniform
conditions in this type of system. This is because the temperature
of cooling air for power modules at the bottom is low, and the
temperature of cooling air for power modules at the top becomes
high. It is difficult to cool upper power modules with the same
efficiency as lower power modules even by increasing the flow rate
over power module surfaces when upper power module cooling air
temperature has become high. For this reason power modules near the
air intakes can be cooled efficiently, but power modules near the
exhaust outlets are difficult to cool efficiently and this system
has the drawback that temperature differential develops over power
modules housed in the holder-case. This has the deleterious effect
that power modules, which are near exhaust outlets and very
difficult to efficiently cool, become hot and easily degraded.
[0009] As shown in the cross-section view of FIG. 2, the power
supply apparatus cited in the later patent application directs
cooling air into the holder-case 222 from intermediate positions
along the holder-case 222. Air directed into the holder-case 222
from intermediate positions supplies cool air to regions near the
outlet and makes the inside temperature of the holder-case 222
uniform. This system can reduce the temperature differential across
the holder-case 222, but the flow rate of air inside drops due to
air entering from intermediate positions along the holder-case 222.
To efficiently cool power modules 221, it is important to lower the
temperature of the cooling air, but it is also important to
increase the flow rate of air over the surfaces of the power
modules 221. Even if cooling air temperature is lowered, the region
of air immediately in contact with the surface of a power module
will rise in temperature if flow rate slows. Since a power module
221 is cooled by the air in immediate contact with its surface, it
cannot be efficiently cooled if the temperature of this region of
air becomes high.
[0010] The present invention was developed to correct these types
of drawbacks seen in prior art power supply apparatus. Thus it is a
primary object of the present invention to provide a power supply
apparatus which can cool all of the plurality of power modules
housed in a holder-case more uniformly and effectively prevent
battery performance degradation caused by temperature
differentials.
[0011] The above and further objects and features of the invention
will more fully be apparent from the following detailed description
with accompanying drawings.
SUMMARY OF THE INVENTION
[0012] The power supply apparatus of the present invention is
provided with a plurality of power modules, a holder-case which
houses the power modules arranged in rows in a parallel fashion and
which cools the power modules by passing air through the inside of
the case, and a fan which forcibly supplies air to the holder-case
or intakes air through the holder-case. The holder-case is
box-shaped and has a first surface plate and a second surface plate
disposed on opposite sides. A plurality of power modules are
arranged side-by-side in line with the plane of the first and
second surface plates in a plurality of columns. Further, walls are
established between the plurality of power modules laterally
arrayed in the holder-case. The walls are located between the first
surface plate and the second surface plate. The interior of the
holder-case is divided into a plurality of columns of partitions by
the walls, and power modules are disposed in each partition column.
The surfaces of partition walls facing power modules follow the
contour of the surfaces of the power modules, and cooling ducts of
uniform width are established between power module surfaces and
partition walls facing the power modules. Air forced into the
partitions has its flow directed along power module surfaces by the
cooling ducts. In addition, the holder-case has flow inlets opened
through the first surface plate to divide air flow and direct it
into the cooling ducts of the plurality of partition columns.
Exhaust outlets are also opened through the second surface plate to
expel air which has passed through the plurality of cooling ducts.
The power supply apparatus uses the fan to divide and divert air
flow through the first surface plate flow inlets into the plurality
of partitions, passes air through the cooling ducts to cool the
power modules, expels air which has performed its cooling function
through second surface plate exhaust outlets, and thereby cools the
power modules disposed inside the plurality of partition
columns.
[0013] This configuration of power supply apparatus has the
characteristic that all of the plurality of power modules housed in
the holder-case can be more uniformly cooled, and battery
performance degradation caused by temperature differentials can be
effectively prevented. This is because the power supply apparatus
of the present invention divides the interior of the holder-case
with walls into a plurality of columns of partitions, disposes
power modules in each partition column, establishes cooling ducts
of uniform width via partition walls which follow power module
contours, and causes air forced into the partitions to flow along
power module surfaces via the cooling ducts. Since the cooling
ducts in this configuration of power supply apparatus are uniform
in width, the flow rate of air in the holder-case does not decrease
and power modules can be efficiently cooled. Further, since the
cooling ducts of this power supply apparatus are made to follow the
surfaces of the power modules, air flowing through the cooling
ducts has to make direct contact with all regions of the surfaces
of the power modules, and cooling can be extremely efficient and
uniform.
[0014] In a power supply apparatus of the present invention,
cooling ducts can be made uniform in width around the entire
perimeter of each power module. Further, it is preferable to
arrange the plurality of power modules in a parallel fashion and in
an array with a plurality of rows and a plurality of columns inside
the holder-case of a power supply apparatus of the present
invention.
[0015] The plurality of power modules of a power supply apparatus
of the present invention may be housed in the holder-case in a two
row array, In that case, at least one dead air space can be
established in the upstream partition of the first row disposed on
the side of the first surface plate. In this power supply
apparatus, the downstream partition cooling ducts can be made
nearly constant in width over approximately the entire power module
circumference, and the width of the upstream partition cooling
ducts can be made wider than the width of the downstream partition
cooling ducts to establish at least one dead air space. The
upstream partition cooling ducts can be made nearly constant in
width over approximately half the power module circumference, in
the remaining half they can be made wider to establish dead air
spaces. The dead air spaces can be established on the downstream
side of the upstream partition. Further, a plurality of dead air
spaces can be established around approximately the entire power
module circumference in the upstream partition. The upstream
partition can be square-shaped in a cross-section view to establish
a dead air space at each part of its four corners. Furthermore, the
width of cooling ducts between the upstream and downstream sides in
the upstream partition can be equal to the width of cooling ducts
of the downstream partition.
[0016] Further, in a power supply apparatus of the present
invention with a plurality of power modules housed in the
holder-case in a two row array, a bypass may also be established to
direct air flow from the upstream partition of the first row
adjacent to the first surface plate to the downstream partition of
the second row adjacent to the second surface plate.
[0017] Still further, in a power supply apparatus of the present
invention with a plurality of power modules housed in a plurality
of rows in the holder-case, the plurality of power modules in
adjacent rows may also be offset.
[0018] It is preferable to provide retaining projections extending
from partition walls facing power modules. The ends of these
retaining projections contact the surface of a power module and
hold that power module in place inside the partition.
[0019] Finally, it is preferable for the power modules and
partitions to be shaped as circular columns, and disposition of
power modules at partition centers can establish cooling ducts of
uniform width.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a cross-section view of a prior art power supply
apparatus.
[0021] FIG. 2 is a cross-section view of another prior art power
supply apparatus.
[0022] FIG. 3 is an oblique cross-section view of an embodiment of
the power supply apparatus of the present invention.
[0023] FIG. 4 is a side view of a power module housed in the power
supply apparatus shown in FIG. 3.
[0024] FIG. 5 is an exploded cross-section view of the power module
shown in FIG. 4.
[0025] FIG. 6 is a cross-section view at the line A-A of the power
supply apparatus shown in FIG. 3.
[0026] FIG. 7 is a cross-section view of another embodiment of the
power supply apparatus of the present invention.
[0027] FIG. 8 is a cross-section view of another embodiment of the
power supply apparatus of the present invention.
[0028] FIG. 9 is a cross-section view of another embodiment of the
power supply apparatus of the present invention.
[0029] FIG. 10 is a cross-section view of another embodiment of the
power supply apparatus of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0030] The power supply apparatus shown in FIG. 3 is provided with
a plurality of power modules 1, a holder-case 2 which houses these
power modules 1, and a fan 9 to cool power modules 1 in the
holder-case 2. The holder-case 2 holds the power modules 1 arranged
in a parallel fashion of a plurality of rows and columns, and cools
the power modules 1 with air which passes through the case.
[0031] A power module 1 is a plurality of rechargeable batteries or
high capacitance super-capacitors joined in a linear fashion. For
example, power modules 1 may have six series connected rechargeable
batteries 6 joined in a straight line. A power module using
super-capacitors has a plurality of super-capacitors connected in
parallel or series. However, a power module 1 may also be made up
of a single rechargeable battery or super-capacitor. The power
module 1 shown in FIG. 4 has circular cylindrical rechargeable
batteries 6 joined in a straight line by dish-shaped connectors 7.
Electrode terminals 5 comprising a positive electrode terminal 5A
and a negative electrode terminal 5B are connected at the ends of a
power module 1.
[0032] The structure for connecting rechargeable batteries 6 in a
straight line with dish-shaped connectors 7 is shown FIGS. 4 and 5.
In a power module 1 of this structure, a disk region 7A of a
dish-shaped connector 7 is weld-connected to the positive terminal
of a circular cylindrical battery 6. The disk region 7A of the
dish-shaped connector 7 is provided with projections 7a for welding
to the positive terminal of the circular cylindrical battery 6.
When the projections 7a of the dish-shaped connector 7 are welded
to the positive terminal, welding electrode rods push on the top
surfaces of the projections 7a. To prevent short circuits between
the dish-shaped connector 7 and the circular cylindrical battery 6,
a ring-shaped insulator 8 is sandwiched between the dish-shaped
connector 7 and the circular cylindrical battery 6.
[0033] In addition, a circular cylindrical battery 6 is inserted
into the dish-shaped connector 7 flange region 7B to connect the
negative terminal of the circular cylindrical battery 6, which is
its outer case 6A, with the flange region 7B. Similar to the disk
region 7A, the flange region 7B also has projections 7a provided on
its inner surface for welding to the battery outer case 6A. During
welding, welding electrode rods push on the outsides of the flange
region 7B projections 7a.
[0034] Although not illustrated, series connected batteries can be
joined without using dish-shaped connectors by weld-connection to
the facing sides of lead-plates bent in U-shapes. In this power
module, battery terminals are welded to facing sides of U-shaped
lead-plates by passing a high current pulse through the batteries
in the direction of battery discharge. Further, metal plates can
also be sandwiched between positive and negative battery terminals,
and a high current pulse can be passed through the batteries in
their direction of discharge to weld the metal plates to the
battery terminals.
[0035] Still further, positive and negative battery terminals of a
power module can also be directly welded together with no
intervening metal plate between batteries. Here, conical
projections are provided on the upper surface of a battery sealing
plate, which is the positive electrode terminal, and these
projections are welded to the negative electrode terminal of an
adjacent battery by passing of a high current pulse.
[0036] Power modules, which have a plurality of rechargeable
batteries 6 connected in series, have the positive side of the
batteries 6 connected to a positive terminal 5A and the negative
side connected to a negative terminal 5B.
[0037] Rechargeable batteries 6 of the power modules 1 are
nickel-hydrogen batteries. However, batteries such as
nickel-cadmium batteries or lithium-ion batteries may also be used
as the rechargeable batteries 6 of the power modules 1.
[0038] Although not illustrated, temperature sensors are fixed to
the surface of each rechargeable battery of the power modules.
Temperature sensors are devices which can measure battery
temperature. Preferably, PTC devices which change electrical
resistance with battery temperature are used as temperature
sensors. Temperature sensors fixed to the surface of each battery 6
are connected linearly and in series via sensor leads, which extend
along, and are fixed lengthwise to the surface of the power
modules. Temperature sensors and sensor leads are attached to
battery surfaces by material such as heat-shrink tubing which
covers the surfaces.
[0039] As shown in FIG. 3, the holder-case 2 is box-shaped having a
first surface plate 2a and a second surface plate 2b as opposing
surfaces. A plurality of rows and columns of power modules 1 are
arranged in planes parallel to the first surface plate 2a and
second surface plate 2b. The holder-case 2 of FIG. 3 houses two
rows and eight columns of power modules 1 in its interior. However,
although it is not illustrated, the plurality of power modules
housed in the holder-case of the power supply apparatus of the
present invention may also be arranged in one row, or in three or
more rows. A power supply apparatus with a plurality of power
modules arranged in one row has the characteristic that each power
module column can be efficiently cooled. A power supply apparatus
with a plurality of power modules arranged in three or more rows
has the characteristic that many power modules can be housed in a
compact fashion.
[0040] The holder-case 2 is provided with upper and lower
cover-casings 2A and an intermediate-casing 2B disposed between the
cover-casings 2A. The cover-casings 2A are made up of a first
cover-casing formed as a single unit with the first surface plate
2a, and a second cover-casing formed as a single unit with the
second surface plate 2b. The cover-casings 2A and the
intermediate-casing 2B overall are formed from plastic, and
assembly primarily of these casings results in the holder-case
2.
[0041] In addition, the holder-case 2 is provided with walls 3
between the eight columns of power modules 1. The walls 3 extend
from the first surface plate 2a to the second surface plate 2b and
divide the interior into a plurality of partitions 4. The walls 3
of holder-case 2 shown in FIG. 3 have two end regions 3A formed as
single units with the upper and lower cover-casings 2A and a center
region 3B formed as a single unit with the intermediate-casing 2B.
These regions are joined without gaps at the interfaces. In this
wall 3 structure, both end regions 3A mate with the first surface
plate 2a and the second surface plate 2b. However, although it is
not illustrated, the walls may also be formed in entirety as single
units with the cover-casings, or as a single unit with the
intermediate-casing. In the case where walls are formed in entirety
as a single unit with the intermediate-casing, both ends of the
walls extend to the first and second surface plates and contact
their inside surfaces. The first and second surface plates are
tightly joined to the walls in a manner which avoids air leaks.
[0042] Power modules 1 are disposed in each partition 4. In the
holder-case 2 of the figures, two rows of power modules 1 are
disposed in each partition 4. As shown in FIG. 6, retaining
projections 10 are formed by single piece construction protruding
from partition 4 walls to hold power modules 1 in fixed positions
within the partitions 4. Retaining projections 10 are formed as
single pieces with the cover-casings 2A and the intermediate-casing
2B, and power modules 1 are retained in fixed positions by
sandwiching them between the retaining projections 10 of the
cover-casings 2A and intermediate-casing 2B. Power modules 1 are
held by the retaining projections 10 in a manner that creates gaps
through which air can flow between the power modules 1 and the
inside surfaces of the partitions 4. Retaining projections 10
extend laterally with respect to the power modules 1.
[0043] The walls 3 are formed with surfaces 3a, which face power
modules 1, made to follow power module surface contours. Cooling
ducts 17 of uniform width are thereby established between power
module surfaces 1A and wall surfaces 3a to uniformly cool the power
modules 1 disposed in each partition 4. The cooling ducts 17 of the
partitions 4 shown in FIG. 3 have approximately uniform width over
the entire perimeter of the power modules 1. In the power supply
apparatus of FIG. 3, the power modules 1 and the partitions 4 are
shaped as circular columns, and cooling ducts 17 of constant width
are established by centering power modules 1 within the partitions
4. Although it is not illustrated, power modules may also be shaped
as square columns. In a power supply apparatus housing power
modules of this shape, both the power modules and the partitions
are shaped as square columns, and again cooling ducts of constant
width can be established around power module perimeters by
centering the power modules within the partitions.
[0044] This configuration of power supply apparatus has the
characteristic that power modules 1 can be cooled by air, which is
directed into a partition 4, and that air is made to flow at high
flow rates over the entire perimeters of the power modules 1.
However, the power supply apparatus of the present invention may
also have partitions shaped as shown in FIGS. 7 and 8. The
holder-case 72 of the power supply apparatus shown in FIG. 7 houses
power modules 71 arranged in two rows. The cooling ducts 717 of the
upstream partitions 74A in the first row disposed on the side of
the first surface plate 72a are made nearly constant in width over
approximately half the power module 71 circumference, and are made
wider over the remaining half to establish dead air spaces 718. The
cooling ducts 717 of the downstream partitions 74B are made nearly
constant in width over approximately the entire power module 71
circumference. The dead air spaces 718 have large volume compared
with the cooling ducts 717, and air passing through these dead air
spaces 718 decreases in flow rate to adjust power module 71 cooling
effectiveness to a lower level.
[0045] In the power supply apparatus of FIG. 8, bypasses 819 are
established to direct air flow from upstream partition 84A dead air
spaces 818 to downstream partitions 84B. The upstream partitions
84A and the downstream partitions 84B of the holder-case 82 of FIG.
8 are connected both at the center and through the bypasses 819.
Bypasses 819 extend in a tangential direction from both sides of a
dead air space 818 to connect with a downstream partition 84B.
[0046] While avoiding over-cooling of power modules 71, 81 in the
upstream partitions 74A, 84A of holder-cases 72, 82 shaped as shown
in FIGS. 7 and 8, power modules 71, 81 in downstream partitions
74B, 84B are more efficiently cooled. These holder-cases 72, 82
thereby have the characteristic that power modules 71, 81 disposed
in upstream partitions 74A, 84A and in downstream partitions 74B,
84B can be cooled more uniformly. This is because high flow rate
air is not made to flow around the entire circumference of power
modules 71, 81 disposed in upstream partitions 74A, 84A, but high
flow rate air is made to flow around the entire circumference of
power modules 71, 81 disposed in downstream partitions 74B, 84B.
Since air which divides and flows into each partition 74, 84 flows
from the upstream partition 74A, 84A to the downstream partition
74B, 84B, the temperature of the air becomes higher when it passes
through the downstream partition 74B, 84B than when it passes
through the upstream partition 74A, 84A. This is because the air
absorbs thermal energy when it passes through the upstream
partition 74A, 84A cooling a power module 71, 81. If a power supply
apparatus is designed to pass air through both the upstream
partition and the downstream partition at the same flow rate and
that flow rate is set to cool a power module in the downstream
partition to a preferred temperature, the upstream partition can be
over-cooled. As shown in FIGS. 7 and 8, if a dead air space 718,
818 is established in part of the upstream partition 74A, 84A to
reduce the flow rate of air flowing over the power module 71, 81
surface, the cooling efficiency for the power module 71, 81 in the
upstream partition 74A, 84A can be adjusted to an optimal value.
Consequently, power modules 71, 81 disposed in the upstream
partition 74A, 84A and in the downstream partition 74B, 84B can be
cooled uniformly. In FIGS. 7 and 8, 72A, 82A are cover-casings,
72B, 82B are intermediate-casings, 73A, 83A are end regions, and
73B, 83B are center regions of the holder-case 72, 82 walls. In
FIG. 8, 817 designates cooling ducts.
[0047] Further, a power supply apparatus can also have such a
structure as shown in FIG. 9. In the power supply apparatus, power
modules 91 are housed in the holder-case 92 in a two row array and
a plurality of dead air spaces 918 are established in the upstream
partition 94A of the first row disposed on the side of the first
surface plate 92a. The width of cooling ducts 917 of the upstream
partition 94A is made wider than the width of cooling ducts 917 of
the downstream partition 94B of the second row disposed on the side
of the second surface plate 92b to establish dead air spaces 918.
The cooling ducts 917 of the downstream partition 94B are made
nearly constant in width over approximately the entire power module
91 circumference. The width of cooling ducts 917 of the upstream
partition 94A can be made wider over approximately the entire power
module 91 circumference to establish dead air spaces 918.
[0048] The upstream partition 94A shown in FIG. 9 is square-shaped
in a cross-section view and a power module 91 is centered within
the upstream partition 94A. In the square-shaped upstream partition
94A, each part of its four corners is made wide to establish a dead
air space 918. However, the upstream partition 94A can be also
square-shaped with each part of the four corners curved. Further,
the cooling ducts 917 between the upstream and downstream sides in
the upstream partition 94A are made narrow in width to be equal to
the width of cooling ducts 917 of the downstream partition 94B. The
power supply apparatus of this type has a characteristic that a
plurality of power modules 91 can be uniformly arranged in two
rows. In a power supply apparatus with the above-mentioned
configuration, the flow rate of air passing through each partition
94 can be adjusted most suitably by formation of vertical and
bilateral pairs of dead air spaces established in the upstream
partition and large capacity. In FIG. 9, 92A are cover-casings, 92B
is the intermediate-casing, 93A are the end regions, and 93B is the
center region.
[0049] The holder-case 2 divides the flow of cooling air and passes
it through each partition 4. To realize this, flow inlets 13 are
opened through the first surface plate 2a to divide the air flow
and direct it into each partition 4, and exhaust outlets 14 are
opened through the second surface plate 2b to expel air from each
partition 4 to the outside.
[0050] In the holder-case 2, 72, 82,92 of FIGS. 3, 7 to 9, slit
shaped flow inlets 13, 713, 813,913 are opened through the first
surface plate 2a, 72a, 82a, 92a positioned at the center region of
the partitions 4, 74, 84, 94 and slit shaped exhaust outlets 14,
714, 814, 914 are opened through the second surface plate 2b, 72b,
82b, 92b. The slit shaped flow inlets 13, 713, 813, 913 and exhaust
outlets 14, 714, 814, 914 extend along the lengthwise direction of
the power modules 1, 71, 81, 91. This configuration of holder-case
2, 72, 82, 92 has the characteristic that cooling air can be made
to flow rapidly over power module 1, 71, 81, 91 surfaces for
efficient cooling.
[0051] The power supply apparatus of FIG. 3 is provided with an air
inlet duct 15 at the surface of the first surface plate 2a. The air
inlet duct 15 connects with a fan 9, and the fan 9 forcibly
supplies cooling air into the inlet duct 15. Inlet duct 15 cooling
air flow is divided among each flow inlet 13 and introduced into
each partition 4. In the power supply apparatus shown in FIG. 3,
the plurality of flow inlets 13 opened through the first surface
plate 2a all have equal area. However, although it is not
illustrated, the power supply apparatus may also have smaller flow
inlets at the upstream end of the air inlet duct than at the
downstream end of the air inlet duct. This is for the purpose of
passing cooling air uniformly through all partitions. Since cooling
air supplied by the fan has higher pressure at the upstream end of
the air inlet duct, large quantities of air can be supplied through
small flow inlets. Since cooling air pressure decreases at the
downstream end of the air inlet duct, flow inlet area can be
increased to increase the amount of air supplied to the downstream
partitions. Consequently, this configuration of power supply
apparatus can supply cooling air uniformly to all partitions.
[0052] As shown by the broken lines in FIG. 3, the power supply
apparatus may be provided with an air outlet duct 16 at the surface
of the second surface plate 2b, and this outlet duct 16 may also
connect with a fan 9. The fan 9 forcibly intakes cooling air from
the outlet duct 16 and exhausts it. The outlet duct 16 joins air
flow expelled from each partition 4 and exhausts it. In the power
supply apparatus shown in FIG. 3, the plurality of exhaust outlets
14 opened through the second surface plate 2b all have equal area.
However, although it is not illustrated, the power supply apparatus
may also have larger exhaust outlets at the upstream end of the air
outlet duct than at the downstream end of the outlet duct. This is
for the purpose of passing cooling air uniformly through all
partitions. Since the fan efficiently intakes cooling air at the
downstream end of the outlet duct, large quantities of air can be
expelled from small exhaust outlets. Consequently, this
configuration of power supply apparatus can pass cooling air
uniformly through all partitions.
[0053] In particular, the exhaust outlet corresponding to a flow
inlet at the downstream end of the outlet duct can be made smaller
than the exhaust outlet corresponding to a flow inlet at the
upstream end. In this power supply apparatus, flow inlets gradually
increase in size from the upstream end to the downstream end, and
exhaust outlets gradually decrease in size from the upstream end to
the downstream end. In this power supply apparatus, air flow rate
from a narrow exhaust outlet can be made faster than that from a
wide exhaust outlet. For this reason, even power modules located at
a distance from a fan can be efficiently cooled.
[0054] Further, as shown in FIGS. 7 to 9, the power supply
apparatus may be provided with an air inlet duct 715, 815, 915 at
the surface of the first surface plate 72a, 82a, 92a and an air
outlet duct 716, 816, 916 at the surface of the second surface
plate 72b, 82b, 92b. In this power supply apparatus, a fan may be
connected to either or both the inlet duct 715, 815, 916 and the
outlet duct 716, 816, 916 to forcibly induce air flow. In this type
of power supply apparatus having an inlet duct 715, 815, 915 and an
outlet duct 716, 816, 916 the air inlet location and outlet
location can be specified.
[0055] In the power supply apparatus described above, two rows of
power modules 1, 71, 81, 91 are arranged in vertically aligned
columns as shown in the figures. However, in the power supply
apparatus of the present invention, a plurality of rows of a
plurality of power modules may also be arranged with power modules
of adjacent rows offset from vertical alignment. The power supply
apparatus shown in FIG. 10 has power modules 101 arranged in two
rows with their positions slightly shifted left and right out of
vertical alignment. In particular, the power supply apparatus shown
in FIG. 10 has each row of power modules 101 offset to inclining
the direction of air flow from the flow inlets 1013 to the exhaust
outlets 1014 compared to a vertical line from the first surface
plate 102a to the second surface plate 102b. For this reason the
system has the characteristic that air supplied by the inlet duct
1015 can be rapidly directed into flow inlets 1013 and induced to
flow in the upstream partitions 104A. The system also has the
characteristic that air passed through the downstream partitions
104B can be smoothly exhausted from the exhaust outlets 1014 to the
outlet duct 1016. In FIG. 10, 102 is the holder-case, 102A are
cover-casings, 102B is the intermediate-casing, 104 are partitions,
and 1017 are cooling ducts.
[0056] As this invention may be embodied in several forms without
departing from the spirit of essential characteristics thereof, the
present embodiment is therefore illustrative and not restrictive,
since the scope of the invention is defined by the appended claims
rather than by the description preceding them, and all changes that
fall within the meets and bounds of the claims or equivalence of
such meets and bounds thereof are therefore intended to be embraced
by the claims.
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