Technical Field
[0001] The present invention relates to an outdoor unit applied to, for example, a multi-air-conditioning
apparatuses for buildings, and an air-conditioning apparatus provided with the outdoor
unit.
Background Art
[0002] In conventional air-conditioning apparatuses such as multi-air-conditioning apparatuses
for buildings, a refrigerant is circulated between an outdoor unit that is a heat
source unit disposed outside the building and indoor units that are disposed in rooms
of the building, for example. In such an air-conditioning apparatus, the refrigerant
transfers heat to or receives heat from air, so that the thus heated or cooled air
heats or cools the air-conditioned space. An air-conditioning apparatus of this type
including a corresponding indoor unit is disclosed, e.g., in
JP H10 220824 A. The document
JP H10 220824 A discloses an outdoor unit using a flammable refrigerant, comprising a housing, a
compressor, a heat-source-side heat exchanger disposed along a part of an inner wall
of the housing, an outdoor air-sending device and an electrical component box accommodating
a controller and an electrical component.
[0003] In the outdoor unit of the air-conditioning apparatus, many electrical components
are mounted, such as a compressor, a solenoid valve, a fan motor. Further, in order
to drive these electrical components, an inverter device and a substrate are accommodated
in an electrical component box and disposed in the outdoor unit. The electrical component
box has slits or holes in the upper or lower surface, or has a large heat sink. The
reason for this is to allow air to flow into the electrical components and thus to
suppress temperature increase by the electronic parts inside the electrical component
box.
[0004] In recent years, from the viewpoint of global warming, there has been a move to restrict
the use of HFC-based refrigerants having high global warming potential (for example,
R410A, R404A, R407C, R134a, and so on). Accordingly, air-conditioning apparatuses
that use refrigerants having low global warming potential (for example, R32, HFO1234yf,
HFO1234ze(E), and a mixture of these refrigerants) have been proposed. However, these
refrigerants having low global warming potential are all flammable, and might enter
the electrical component box when the refrigerant leaks.
[0005] In view of such an issue, there has been disclosed a technique in which a non-contact
switch is used in an electrical component, and in which a film that passes only gas
is provided on an electrical component box (see, for example, Patent Literature 1).
Citation List
Patent Literature
[0006] Patent Literature 1: Japanese Unexamined Patent Application Publication No.
6-101913 (paragraphs [0030] - [0033], [0045], and so on)
Summary of Invention
Technical Problem
[0007] However, if a non-contact switch is provided or a film that passes only gas is used
as in the technique disclosed in Patent Literature 1, costs are significantly increased.
Moreover, since the film severely degrades over time, it is difficult to ensure long-term
reliability. Therefore, the film needs to be replaced periodically, making maintenance
of the system very troublesome and expensive.
[0008] The present invention has been made to solve the above problems, and aims to provide
an outdoor unit with significantly improved safety while reducing cost increase, and
an air-conditioning apparatus provided with the outdoor unit. Solution to Problem
[0009] An outdoor unit according to the present invention constitutes part of an air-conditioning
apparatus using a flammable refrigerant. The outdoor unit includes a housing; a compressor
disposed inside the housing and configured to compress a refrigerant; a heat-source-side
heat exchanger disposed along a part of an inner wall of the housing, and into which
the refrigerant discharged from the compressor or the refrigerant that is to be suctioned
into the compressor flows; an outdoor air-sending device disposed on a top of the
housing and configured to form an air flow inside the housing; a controller configured
to control the compressor and the outdoor air-sending device; and an electrical component
disposed in the housing and configured to accommodate at least the controller and
an electrical component used for controlling a drive unit including in the air-conditioning
apparatus. The electrical component box is disposed such that a bottom surface of
the electrical component box is located at a height greater than 1/3 a height of the
housing from a bottom surface of the housing. The controller and the electrical component
are disposed such that bottom surfaces thereof are located at a height greater than
1/3 a height of the electrical component box from the bottom surface of the electrical
component box. Advantageous Effects of Invention
[0010] The outdoor unit according to the present invention, the installation position of
the electrical component box and the installation positions of the controller and
relays accommodated in the electrical component box are specified. Therefore, even
if a flammable refrigerant leaks, it is possible to significantly suppress entry of
the leaked refrigerant into the electrical component box. Further, even if the leaked
refrigerant enters the electrical component box, the controller and the relays are
not exposed to the refrigerant. Therefore, according to the outdoor unit of the present
invention, the safety is significantly improved while reducing cost increase.
Brief Description of Drawings
[0011]
[Fig. 1] Fig. 1 is a schematic circuit diagram illustrating an exemplary circuit configuration
of an air-conditioning apparatus according to Embodiment of the present invention.
[Fig. 2] Fig. 2 is a refrigerant circuit diagram illustrating the flow of a refrigerant
when the air-conditioning apparatus is in a cooling operation mode according to Embodiment
of the present invention.
[Fig. 3] Fig. 3 is a refrigerant circuit diagram illustrating the flow of a refrigerant
when the air-conditioning apparatus is in a heating operation mode according to Embodiment
of the present invention.
[Fig. 4] Fig. 4 is a circuit diagram schematically illustrating an electrical connection
state of the air-conditioning apparatus according to Embodiment of the present invention.
[Fig. 5] Fig. 5 is a schematic perspective view illustrating the external view of
an outdoor unit according to Embodiment of the present invention.
[Fig. 6] Fig. 6 is a schematic side view of the outdoor unit as viewed from a direction
A (the front) of Fig. 5 according to Embodiment of the present invention.
[Fig. 7] Fig. 7 is a diagram illustrating a cross section B-C of the outdoor unit
of Fig. 6 according to Embodiment of the present invention.
[Fig. 8] Fig. 8 is a schematic diagram schematically illustrating the layout of electrical
components in an electrical component box mounted in the outdoor unit according to
Embodiment of the present invention.
[Fig. 9] Fig. 9 is a schematic diagram schematically illustrating an installation
example of a wide bandgap semiconductor that constitutes at least a part of devices
of a controller mounted in the outdoor unit according to Embodiment of the present
invention.
Description of Embodiments
[0012] Hereinafter, Embodiment of the present invention will be described with reference
to the drawings.
[0013] Fig. 1 is a schematic circuit diagram illustrating an exemplary circuit configuration
of an air-conditioning apparatus 100 according to Embodiment of the present invention.
The circuit configuration of the air-conditioning apparatus 100 will be described
in detail with reference to Fig. 1. Fig. 1 illustrates an exemplary case in which
four indoor units 20 are connected. Note that the dimensional relationship between
the components in Fig. 1 and the subsequent drawings may be different from the actual
one. Further, components denoted by the same reference numerals in Fig. 1 and the
subsequent drawings have the same or corresponding functions. This applies throughout
the specification. Furthermore, embodiments of the components that will be described
in the specification are only examples, and the present invention is not limited to
these examples.
[0014] As illustrated in Fig. 1, the air-conditioning apparatus 100 includes an outdoor
unit (heat source unit) 10 and indoor units 20 (indoor units 20a through 20d), which
are connected to and communicate with each other through pipes. That is, in the air-conditioning
apparatus 100, a plurality of indoor units 20 are connected in parallel to the outdoor
unit 10.
[0015] Further, in the air-conditioning apparatus 100, a refrigerant such as R32, HFO1234yf,
HFO1234ze(E), a mixture of R32 and HFO1234yf, and a mixture of R32 and HFO1234ze(E),
is charged. As for HFO1234yf, there are two geometric isomers. One is a trans type
in which F and CF
3 are located at symmetric positions with respect to a double bond, and the other is
a cis type in which F and CF
3 are located on the same side. HFO1234ze(E) in Embodiment is a trans type. According
to the IUPAC nomenclature, the name is trans-1,3,3,3-tetrafluoro-1-propene.
(Outdoor Unit 10)
[0016] The outdoor unit 10 has a function that provides heating or cooling to the indoor
units 20. The outdoor unit 10 includes a compressor 1, an oil separator 2 that separates
a refrigerant and a refrigerating machine oil from each other, a flow switching device
3 such as a four-way valve, a heat-source-side heat exchanger 4, a supercooling heat
exchanger 6 that increases the degree of supercooling during cooling operation so
as to improve the performance, an expansion device 7, an accumulator 5, and an oil
return circuit 8 connecting the oil separator 2 to a downstream pipe of the accumulator
5, which are connected through pipes. Further, in the outdoor unit 10, an opening
and closing valve 9 is provided in a high-pressure pipe, and an opening and closing
valve 11 is provided in a low-pressure pipe. The opening and closing valves 9 and
11 are used by an operator or the like during a service operation. Note that the opening
and closing valves 9 and 11 may be solenoid valves and be turned on/off by relays
33 (described below).
[0017] The compressor 1 suctions the refrigerant, compresses the refrigerant into a high-temperature
and high-pressure state, and transports the refrigerant to a refrigerant circuit.
The compressor 1 may preferably be, for example, a capacity-controllable inverter
compressor or the like. The oil separator 2 is disposed at the discharge side of the
compressor 1, and is configured to separate a refrigerating machine oil that is discharged
together with the refrigerant from the compressor 1, from the refrigerant. The refrigerating
machine oil separated by the oil separator 2 is guided to the downstream side of the
accumulator 5, that is, the suction side of the compressor 1, through the oil return
circuit 8. The flow switching device 3 is disposed at the downstream side of the oil
separator 2, and is configured to switch between the refrigerant flow in the heating
operation mode and the refrigerant flow in the cooling operation mode.
[0018] The heat-source-side heat exchanger (outdoor-side heat exchanger) 4 serves as an
evaporator during heating operation and serves as a radiator (or a condenser) during
cooling operation. The heat-source-side heat exchanger 4 exchanges heat between air
supplied from an outdoor air-sending device (an outdoor air-sending device 44 of Fig.
7), such as a fan, and the refrigerant. The accumulator 5 is disposed at the suction
side of the compressor 1, and is configured to store excess refrigerant due to the
difference in the heating operation mode and the cooling operation mode, and excess
refrigerant for a transient change in operation (change in the number of operating
indoor units 20, for example).
[0019] The supercooling heat exchanger 6 exchanges heat between the refrigerant (hereinafter
also referred to as a main refrigerant) flowing between the heat-source-side heat
exchanger 4 and the opening and closing valve 9 and the refrigerant (hereinafter also
referred to as a bypass refrigerant) that has been branched at a position between
the heat-source-side heat exchanger 4 and the opening and closing valve 9 and decompressed
by the expansion device 7 so as to increase the degree of supercooling during cooling
operation. That is, the supercooling heat exchanger 6 exchanges heat between refrigerants.
Note that the bypass refrigerant is a refrigerant that flows through a bypass 12 branching
off from a position between the heat-source-side heat exchanger 4 and the opening
and closing valve 9 and extending through the expansion device 7 and the bypass refrigerant
side of the supercooling heat exchanger 6 to the upstream side of the accumulator
5. The supercooling heat exchanger 6 may be disposed at any position where the supercooling
heat exchanger 6 can exchange heat between the refrigerants.
[0020] The expansion device 7 is disposed in the bypass 12 at the upstream side of the supercooling
heat exchanger 6 through which the bypass refrigerant flows. The expansion device
7 decompresses the refrigerant flowing through the bypass 12 and adjusts the flow
rate of the bypass refrigerant that flows into the supercooling heat exchanger 6.
The expansion device 7 may preferably be one having a variably controllable opening
degree such as an electronic expansion valve, for example.
[0021] The oil return circuit 8 is disposes so as to connect the lower side of the oil separator
2 to the downstream pipe of the accumulator 5. Note that pressure reducing means 8a
including a capillary tube is disposed in the oil return circuit 8. That is, the refrigerating
machine oil that has been separated by the oil separator 2 flows through the oil return
circuit 8, is decompressed by the pressure reducing means 8a, and then is guided to
the downstream side of the accumulator 5.
[0022] Further, the outdoor unit 10 includes a controller 50. The controller 50 performs
integrated control of the entire system of the air-conditioning apparatus 100. More
specifically, the controller 50 controls the driving frequency of the compressor 1,
the rotation speed of the outdoor air-sending device, switching of the flow switching
device 3, the opening degree of the expansion device 7, and so on. That is, the controller
50 controls actuators (drive units of the compressor 1, the flow switching device
3, the outdoor air-sending device, the expansion device, and so on), in accordance
with detection information from various detection devices (not illustrated) and instructions
from a remote controller. Note that the outdoor unit 10 includes the relays 33 (relays
33a through 33d). The relays 33 turn on/off a solenoid valve (not illustrated in Figs.
1 through 3), the opening and closing valve 9, the opening and closing valve 11, and
so on. Note that the relays 33 will be described with reference to Fig. 8.
(Indoor Units 20)
[0023] Each indoor unit 20 has a function of heating or cooling the air-conditioned space
such as a room, using the refrigerant supplied from the outdoor unit 10. The indoor
unit 20 includes a use-side heat exchanger (indoor-side heat exchanger) 22 and an
expansion device 21, which are connected in series. More specifically, the expansion
device 21 and the use-side heat exchanger 22 are connected in series in this order
in a direction from the opening and closing valve 9 toward the opening and closing
valve 11.
[0024] The use-side heat exchanger 22 serves as a radiator (or a condenser) during heating
operation and serves as an evaporator during cooling operation. The use-side heat
exchanger 22 exchanges heat between air supplied from an indoor air-sending device
(not illustrated), such as a fan, and the refrigerant, and generates heating air or
cooling air to be supplied to the air-conditioned space. The expansion device 21 serves
as a reducing valve and an expansion valve, and is configured to decompress and expand
the refrigerant. The expansion device 21 may preferably be one having a variably controllable
opening degree such as an electronic expansion valve, for example. Note that the indoor
air-sending device (not illustrated) and the expansion device 21 are controlled by
the controller 50.
[0025] In Embodiment, an exemplary case is illustrated in which four indoor units 20 are
connected. In Fig. 1, the indoor units 20 are illustrated as an indoor unit 20a, an
indoor unit 20b, an indoor unit 20c, and an indoor unit 20d in this order from the
left side (lower side) of Fig. 1. In accordance with the indoor units 20a through
20d, the use-side heat exchangers 22 are illustrated as a use-side heat exchanger
22a, a use-side heat exchanger 22b, a use-side heat exchanger 22c, and a use-side
heat exchanger 22d in this order from the left side (lower side) of Fig. 1. Similarly,
the expansion devices 21 are illustrated as an expansion device 21 a, an expansion
device 21b, an expansion device 21c, and an expansion device 21 d in this order from
the left side (lower side) of Fig. 1. Note that the number of indoor units 20 connected
is not limited to four.
[0026] Operation modes carried out by the air-conditioning apparatus 100 will be described.
(Cooling Operation Mode)
[0027] Fig. 2 is a refrigerant circuit diagram illustrating the flow of the refrigerant
when the air-conditioning apparatus 100 is in the cooling operation mode. Fig. 2 illustrates
an exemplary case in which all the indoor units 20 are driven. In the cooling operation
mode, the flow switching device 3 is switched such that the heat-source-side heat
exchanger 4 serves as a radiator, and the use-side heat exchangers 22 serve as evaporators.
More specifically, the flow switching device 3 is switched such that the refrigerant
discharged from the compressor 1 flows into the heat-source-side heat exchanger 4.
In Fig. 2, the direction of the refrigerant flow is indicated by the arrows.
[0028] A low-temperature and low-pressure refrigerant is compressed by the compressor 1,
and is discharged as a high-temperature and high-pressure gas refrigerant. The high-temperature
and high-pressure gas refrigerant that has been discharged from the compressor 1 flows
through the oil separator 2 and the flow switching device 3 into the heat-source-side
heat exchanger 4. In the oil separator 2, a refrigerating machine oil that is discharged
together with the refrigerant from the compressor 1 is separated from a refrigerant
gas. The separated refrigerating machine oil passes through the oil return circuit
8 and returns to a pipe at the suction side of the compressor 1. On the other hand,
the refrigerant gas that has been separated by the oil separator 2 flows into the
flow switching device 3.
[0029] The high-temperature and high-pressure refrigerant that has flowed into the heat-source-side
heat exchanger 4 exchanges heat with air supplied from the outdoor air-sending device
so as to be liquefied, and flows out of the heat-source-side heat exchanger 4. Part
of the liquid refrigerant flows into the bypass 12, and the other part of the liquid
refrigerant flows into the indoor units 20. The liquid refrigerant (bypass refrigerant)
that has flowed into the bypass 12 is decompressed by the expansion device 7 so as
to turn into a low-pressure two-phase gas-liquid refrigerant. The low-pressure two-phase
gas-liquid refrigerant flows into the supercooling heat exchanger 6, exchanges heat
with a high-pressure liquid refrigerant (main refrigerant) so as to become a low-pressure
gas refrigerant, and flows out of the supercooling heat exchanger 6. The main refrigerant
that has flowed into the supercooling heat exchanger 6 is cooled by the bypass refrigerant,
so that the liquid temperature is reduced (the degree of supercooling is increased).
[0030] Although not illustrated, a pressure sensor and a temperature sensor are provided
at the exit of the bypass 12 of the supercooling heat exchanger 6. On the basis of
information from these sensors, the controller 50 adjusts the opening degree of the
expansion device 7 such that the degree of superheat at the exit of the supercooling
heat exchanger 6 becomes around 5 degrees C.
[0031] The part of liquid refrigerant that has not flowed into the bypass 12 passes through
a pipe connecting the indoor units 20 and the outdoor unit 10, and flows out of the
outdoor unit 10. Then, the liquid refrigerant flows into each of the indoor units
20a through 20d. The refrigerant that has flowed into each of the indoor units 20a
through 20d are expanded (decompressed) by the expansion devices 21a through 21 d,
respectively, and are brought into a low-temperature and low-pressure two-phase gas-liquid
state. Then, the refrigerant in the two-phase gas-liquid state flows into each of
the use-side heat exchangers 22a through 22d.. The refrigerant in the two-phase gas-liquid
state that has flowed into each of the use-side heat exchangers 22a through 22d exchanges
heat with air (indoor air) supplied from the indoor air-sending device (not illustrated)
so as to receive heat from the air and become low-pressure gas refrigerant, and flows
out of each of the use-side heat exchangers 22a through 22d.
[0032] In general, although not illustrated, temperature sensors are provided at the refrigerant
inlet and outlet of each use-side heat exchanger 22. Thus, the amount of the refrigerant
to be supplied to the use-side heat exchanger 22 is adjusted using temperature information
from the temperature sensors at the refrigerant inlet and outlet of the use-side heat
exchanger 22. More specifically, the controller 50 calculates the degree of superheat
(the refrigerant temperature at the exit side - the refrigerant temperature at the
entrance side) in accordance with information from the temperature sensors. Then,
the controller 50 determines the opening degree of the expansion device 21 such that
the degree of superheat is around 2 to 5 degrees C, and adjusts the amount of the
refrigerant to be supplied to the use-side heat exchanger 22.
[0033] The low-pressure gas refrigerant that has flowed out of the use-side heat exchangers
22a through 22d flows out of the indoor units 20a through 20d, passes through a pipe
connecting the indoor units 20 and the outdoor unit 10, and flows into the outdoor
unit 10. The refrigerant that has flowed into the outdoor unit 10 passes through the
flow switching device 3, and flows into the accumulator 5. The refrigerant that has
flowed into the accumulator 5 is separated into a liquid refrigerant and a gas refrigerant,
and the gas refrigerant is suctioned into the compressor 1 again.
[0034] In such cooling operation mode, the degree of superheat is controlled in each indoor
unit 20, and therefore the refrigerant in a liquid state does not flow into the accumulator
5. However, if any one of the indoor units 20 is in a transient state or stopped,
a small amount of the refrigerant in a liquid state (with a quality of about 0.95)
may flow into the accumulator 5. The liquid refrigerant that has flowed into the accumulator
5 evaporates and is suctioned into the compressor 1, or is suctioned into the compressor
1 through an oil return hole (not illustrated) provided in the exit pipe of the accumulator
5.
(Heating Operation Mode)
[0035] Fig. 3 is a refrigerant circuit diagram illustrating the flow of the refrigerant
when the air-conditioning apparatus 100 is in the heating operation mode. Fig. 3 illustrates
an exemplary case in which all the indoor units 20 are driven. In the heating operation
mode, the flow switching device 3 is switched such that the heat-source-side heat
exchanger 4 serves as an evaporator, and the use-side heat exchangers 22 serve radiators.
More specifically, the flow switching device 3 is switched such that the refrigerant
discharged from the compressor 1 flows into the use-side heat exchangers 22. In Fig.
3, the direction of the refrigerant flow is indicated by the arrows.
[0036] A low-temperature and low-pressure refrigerant is compressed by the compressor 1,
and is discharged as a high-temperature and high-pressure gas refrigerant. The high-temperature
and high-pressure gas refrigerant that has been discharged from the compressor 1 passes
through the oil separator and the flow switching device 3, flows through the pipe
connecting the indoor units 20 and the outdoor unit 10, flows out of the outdoor unit
10, and flows into each of the indoor units 20a through 20d. The function of the oil
separator 2 is as described in connection with the cooling operation mode.
[0037] The high-temperature and high-pressure gas refrigerant that has flowed into the indoor
units 20a through 20d exchanges heat with air (indoor air) supplied from the indoor
air-sending device (not illustrated) in each of the use-side heat exchangers 22a through
22d so as to transfer heat to the air and to be liquefied, and flows out of the use-side
heat exchangers 22a through 22d. The refrigerant is expanded (decompressed) by the
expansion devices 21a through 21 d, respectively, and is brought into a low-temperature
and low-pressure two-phase gas-liquid state, and flows out of each of the indoor units
20a through 20d.
[0038] In general, although not illustrated, a temperature sensor and a pressure sensor
are provided at the refrigerant outlet of each use-side heat exchanger 22. Thus, the
amount of the refrigerant to be supplied to the use-side heat exchanger 22 is adjusted
using information from the temperature sensor and the pressure sensor at the refrigerant
outlet of the use-side heat exchanger 22. More specifically, the controller 50 calculates
the degree of supercooling (the saturated temperature obtained by converting the pressure
of the refrigerant detected at the exit side - the refrigerant temperature at the
exit side) in accordance with information from the sensors. Then, the controller 50
determines the opening degree of the expansion device 21 such that the degree of supercooling
is around 2 to 5 degrees C, and adjusts the amount of the refrigerant to be supplied
to the use-side heat exchanger 22.
[0039] The low-temperature and low-pressure refrigerant in the two-phase gas-liquid state
that have flowed out of each of the indoor units 20a through 20d passes through the
pipe connecting the indoor units 20 and the outdoor unit 10, and flows into the outdoor
unit 10. This refrigerant flows into the heat-source-side heat exchanger 4. The low-temperature
and low-pressure refrigerant in the two-phase gas-liquid state that has flowed into
the heat-source-side heat exchanger 4 exchanges heat with air supplied from the outdoor
air-sending device so as to receive heat from the air, so that the quality gradually
increases. Then, the refrigerant turns into a two-phase gas-liquid refrigerant having
a high quality at the exit of the heat-source-side heat exchanger 4, and flows out
of the heat-source-side heat exchanger 4. The refrigerant that has flowed out of the
heat-source-side heat exchanger 4 passes through the flow switching device 3, and
flows into the accumulator 5. The refrigerant that has flowed into the accumulator
5 is separated into a liquid refrigerant and a gas refrigerant, and the gas refrigerant
is suctioned into the compressor 1 again.
(Electrical Configuration of Air-Conditioning Apparatus 100)
[0040] Fig. 4 is a circuit diagram schematically illustrating an electrical connection state
of the air-conditioning apparatus 100. The electrical configuration of the air-conditioning
apparatus 100 will be described with reference to Fig. 4. Note that the installation
position of an electrical component box 30 will be described in detail with reference
to Figs. 5 through 7.
[0041] The controller 50 includes a rectifier 52 that converts an AC voltage of a three-phase
AC power supply 51 into a DC voltage, a reactor 53 that corrects the power factor,
a smoothing capacitor 54, an inverter main circuit 55, an inverter substrate 31 on
which a control circuit 56 that controls the inverter main circuit 55 and so on are
mounted. The controller 50 is connected to a motor 57 of the compressor 1.
[0042] The inverter main circuit 55 converts a DC power smoothed by the smoothing capacitor
54 into an AC power, and includes a plurality of switching devices made of a silicon
(Si) semiconductor or a wide bandgap semiconductor, for example. Wide bandgap semiconductor
is a generic term for a semiconductor device having a greater bandgap than a silicon
(Si) device. Examples of wide bandgap semiconductors include not only a silicon carbide
(SiC) device, but also a gallium nitride (GaN) device and a diamond device. Each switching
device of the inverter main circuit 55 performs a switching operation in accordance
with an operation signal (a PWM signal and a gate signal) transmitted from the control
circuit 56.
[0043] The control circuit 56 includes a microcomputer, and is configured to actually control
driving of various actuators in accordance with detection information from various
detecting means (not illustrated) (for example, a temperature sensor, a pressure sensor,
and so on) and instructions from the remote controller, and thus to perform a heating
operation and a cooling operation. In Fig. 4, only the motor 57 of the compressor
1 is shown for purposes of illustration. Further, not only switching devices but also
diode devices can be made of a wide bandgap semiconductor.
(Installation Position of Electrical Component Box 30)
[0044] Fig. 5 is a schematic perspective view illustrating the external view of the outdoor
unit 10. Fig. 6 is a schematic side view of the outdoor unit 10 as viewed from a direction
A (the front) of Fig. 5. Fig. 7 is a diagram illustrating a cross section B-C of the
outdoor unit 10 of Fig. 6. The installation position of the electrical component box
30 will be described in detail with reference to Figs. 5 through 7. In Fig. 7, the
direction of the air flow is indicated by the arrows. Further, a schematic view of
the outdoor air-sending device 44 is also illustrated in Fig. 7.
[0045] As described above, the outdoor unit 10 constitutes part of the air-conditioning
apparatus 100, and is configured to supply cooling energy or heating energy to the
indoor units 20 connected thereto with a refrigerant pipe. Note that, in the following
description, the side of the outdoor unit 10 viewed from the direction of the arrow
A of Fig. 5 is referred to as a front side thereof.
[0046] As illustrated in Fig. 5, the outdoor unit 10 includes a housing 10a forming an
outer shell of the outdoor unit 10 and has a substantially cuboid shape, and an air
outlet 42 which is provided on the ceiling side of the housing 10a and in which the
outdoor air-sending device is disposed. A front panel 40 is disposed on the front
side of the housing 10a. Further, an air inlet 41 for suctioning air into the housing
10a is formed as an opening in each of the sides of the housing 10a other than the
front side. The electrical component box 30 accommodating the controller 50 and so
on is disposed at the upper part of the front panel 40, that is, the upper part of
the outdoor unit 10. Further, a pipe outlet 43 for removing the pipe connecting the
indoor units 20 and the outdoor unit 10 is formed as an opening in a portion of the
lower side of the front panel 40.
[0047] The components illustrated in Figs. 1 through 3 are accommodated in the housing 10a
of the outdoor unit 10. Of these, the heat-source-side heat exchanger 4 may preferably
be disposed so as to have a substantially C-shaped cross section along the sides (inner
wall) of the housing 10a. Further, the compressor 1 is heavy and therefore is fixed
at the bottom of the housing 10a. The outdoor air-sending device 44 is disposed on
the ceiling side, that is, the air-outlet-42 side of the housing 10a (see Fig. 7).
Further, the electrical component box 30 may preferably be openable and closable about
a hinge with respect to the front panel 40.
[0048] The flow of air in the outdoor unit 10 will be described with reference to Fig. 7.
When the outdoor air-sending device 44 is driven, air is suctioned into the housing
10a through the air inlet 41. The air that has been suctioned into the housing 10a
passes through the heat-source-side heat exchanger 4 disposed in the housing 10a,
and exchanges heat with a refrigerant supplied to the heat-source-side heat exchanger
4. The air that has exchanged heat in the heat-source-side heat exchanger 4 is discharged
outside the outdoor unit 10 from the air outlet 42 of the housing 10a by the outdoor
air-sending device 44. This air flow is formed by the outdoor air-sending device 44.
That is, air flows into the housing 10a from the right side of Fig. 7, and is blown
out to the upper side of the housing 10a.
[0049] As can be seen from Figs. 5 through 7, the electrical component box 30 is attached
to the upper part of the outdoor unit 10. Further, as illustrated in Fig. 7, in order
to ensure smooth air flow, components other than the electrical component box 30 are
not disposed in the upper space inside the housing 10a of the outdoor unit 10. This
is because if components other than the electrical component box 30 are present in
the upper space inside the housing 10a of the outdoor unit 10, the components become
an obstacle to the air flow. On the other hand, the refrigerant circuit components,
such as the compressor 1, the oil separator 2, and the accumulator 5, pipes, and so
on are densely arranged in the lower space inside the housing 10a of the outdoor unit
10 (the area indicated by the broken line in Fig. 7).
[0050] Table 1 shows the refrigerant gas density of the currently promising next-generation
refrigerants at 25 degrees C and atmospheric pressure (101.3 kPa abs). The physical
property values are based on REFPROP Version 9.0 available from NIST (National Institute
of Standards and Technology).
[Table 1]
[0051]
Table 1 List of Refrigerant Gas Density
Refrigerant |
Density [kg/m3] |
R32 |
2.1526 |
HFO1234yf |
4.7654 |
HFO1234ze(E) |
4.7738 |
[0052] It is found from Table 1 that the gas density of the currently promising next-generation
refrigerants is greater than an air density of 1.2 [kg/m
3]. As shown in Table 1, the currently promising next-generation refrigerants are R32,
HFO1234yf, and HFO1234ze(E). That is, the refrigerants shown in Table 1 are heavier
than air, and are likely to settle on the bottom of the outdoor unit 10 when the refrigerants
leak from the outdoor unit 10. This indicates that it is desirable that the electrical
component box 30 accommodating electrical components that can be a source of ignition
be located as high as possible in the housing 10a.
[0053] Accordingly, in the outdoor unit 10, the electrical component box 30 is disposed
such that a bottom surface E1 of the electrical component box 30 is located at a height
greater than 1/3 (line F of Fig. 6) a height h1 of the housing 10a from a bottom surface
E2 of the housing 10a. Thus, even if the refrigerant leaks, the electrical component
box 30 is not exposed to the area where the concentration is greater than the lower
explosive limit.
[0054] It was found that, in the case where the refrigerants shown in Table 1 leak from
a currently widely used outdoor unit, the leaked refrigerants accumulate in the area
below a height of about 10 cm from the bottom surface of the outdoor unit. Accordingly,
it suffices to locate the electrical component box 30 at a height greater than 10
cm from the bottom surface of the outdoor unit. However, in consideration of not only
the safety but also maintainability, airflow resistance, and the like, in the outdoor
unit 10, the electrical component box 30 is disposed such that the bottom surface
E1 of the electrical component box 30 is located at a height greater than 1/3 the
height h1 of the outdoor unit 10 from the bottom surface E2 of the outdoor unit 10
(housing 10a).
(Layout of Electrical Components in Electrical Component Box 30)
[0055] Fig. 8 is a schematic diagram schematically illustrating the layout of electrical
components in the electrical component box 30. The layout of electrical components
in the electrical component box 30 will be described with reference to Fig. 8. As
mentioned above, the controller 50 as an electrical component is accommodated in the
electrical component box 30. The controller 50 includes the inverter substrate 31.
Further, electrical components such as the relays 33a through 33d for turning on/off
a solenoid valve (not illustrated in Figs. 1 through 3), the opening and closing valve
9, the opening and closing valve 11, and so on are accommodated in the electrical
component box 30, in addition to the controller 50. Note that the controller 50 controls
the rotation speed of the motor of the compressor 1 such that the rotation speed varies
from several hertz to several hundred hertz.
[0056] As described above, a wide bandgap semiconductor is used as a part of electronic
parts included in the inverter substrate 31. In Fig. 8, a wide bandgap semiconductor
mounted on the inverter substrate 31 is shown as a wide bandgap semiconductor 32 for
purposes of illustration. As mentioned above, examples of the wide bandgap semiconductor
32 include not only a silicon carbide (SiC) device, but also a gallium nitride (GaN)
device, and a diamond device.
[0057] The semiconductor devices (for example, the inverter main circuit 55 of Fig. 4, and
so on) made of the wide bandgap semiconductor 32 are excel in heat resistance, and
thus can resist high temperatures. Therefore, there is no need to provide a slit and
a hole for suppressing temperature increase inside the electrical component box 30,
so that it is possible to realize a configuration that does not allow ambient air
to easily enter. Accordingly, the electrical component box 30 is made of a non-combustible
material such as sheet metal, and has a configuration such that a cover of the electrical
component box 30 can be removed using a driver or the like from the front side (the
direction A of Fig. 5) so as to allow wires to be connected and to allow services
such as replacing electrical components to be performed. Further, although a hole
through which a wire is inserted is formed in the electrical component box 30, the
hole is sealed by rubber bush or the like.
[0058] Since the electrical component box 30 has the configuration described above, even
if a refrigerant leaks, it is possible to significantly suppress entry of the refrigerant
into the electrical component box 30, and thus to further improve the safety. That
is, the electrical component box 30 is disposed in the upper part of the housing 10a,
and this is one countermeasure against entry of the refrigerant. In addition to that,
a configuration that does not allow ambient air to easily enter is employed, which
further strengthens the countermeasures against entry of refrigerant. Even though
such a configuration that does not allow ambient air to easily enter is employed for
the electrical component box 30, since the wide bandgap semiconductor 32 having excellent
heat resistance is used, it is possible to suppress temperature increase in the electrical
component box 30 by only transferring heat from the electrical component box 30 to
the environment.
[0059] The wide bandgap semiconductor 32 has high heat resistance and is capable of operating
at high temperature, which makes it possible to employ a fan-less structure, or a
radiation-fin-less structure (or a compact radiation fin structure), and thus allows
the electrical component box 30 to have a substantially enclosed structure. Further,
the switching device and the diode device made of the wide bandgap semiconductor 32
have high withstand voltage and have high allowable current density. Therefore, it
is possible to reduce the size of the switching device, and thus to reduce the size
of the semiconductor module having these devices therein. Furthermore, since the wide
bandgap semiconductor 32 has low power loss, it is possible to increase the efficiency
of the switching device, and hence increase the efficiency of the semiconductor module.
[0060] Further, as shown in Fig. 8, in the electrical component box 30, the relays 33a through
33d that can be a source of ignition, and electrical components such as the wide bandgap
semiconductor 32 that can reach a high temperature are located as high as possible.
Accordingly, in the electrical component box 30, the electrical components are disposed
such that bottom surfaces E4 and E5 of the electrical components are located at a
height greater than 1/3 (line G of Fig. 8) a height h2 of the electrical component
box 30 from a bottom surface E3 of the electrical component box 30. Thus, even if
the refrigerant leaks, the electrical components are not exposed to the area where
the concentration is greater than the lower explosive limit. With this configuration,
even if a leaked refrigerant enters from a gap in the electrical component box 30,
the refrigerant accumulates in the lower part of the electrical component box 30.
Therefore, safety is further improved.
[0061] It was found that, in the case where the refrigerants shown in Table 1 enter a currently
widely used electrical component box, the refrigerants that have entered accumulate
in the area below a height of about several tens of centimeters from the bottom surface
of the electrical component box. Accordingly, it suffices to locate the electrical
component box 30 at a height greater than several tens of centimeters from the bottom
surface of the electrical component box. However, in consideration of not only the
safety but also maintainability, operability, and the like, in the outdoor unit 10,
the electrical components are disposed such that the bottom surfaces E4 and E5 of
the electrical components are located at a height greater than 1/3 the height h2 of
the electrical component box from the bottom surface E3 of the electrical component
box 30.
(Suppression of Temperature Increase of Wide Bandgap Semiconductor 32)
[0062] Fig. 9 is a schematic diagram schematically illustrating an installation example
of the wide bandgap semiconductor 32. The following describes the case where safety
is further improved by suppressing temperature increase of the wide bandgap semiconductor
32 with reference to Fig. 9. Fig. 9(a) is a perspective view of the wide bandgap semiconductor
32 and temperature detecting means 34 as viewed from the front, and Fig. 9(b) illustrates
the wide bandgap semiconductor 32 and the temperature detecting means 34 as viewed
from the direction H of Fig. 8.
[0063] Table 2 shows the ignition temperature of each of the currently promising next-generation
refrigerants.
[Table 2]
[0064]
Table 2 List of Ignition Temperature of Refrigerant
Refrigerant |
Ignition Temperature [Degrees C] |
R32 |
648 |
HFO1234yf |
405 |
HFO1234ze(E) |
288 - 293 |
[0065] The ignition temperature shown in Table 2 is the temperature at which a refrigerant
ignites spontaneously. That is, when the wide bandgap semiconductor 32 reaches a temperature
equal to or higher than the temperature shown in Table 2 and the concentration of
the refrigerant becomes equal to or greater than the lower explosive limit, the refrigerant
may ignite. This indicates that the surface temperature of the wide bandgap semiconductor
32, which generates the highest temperature among the electrical components in the
electrical component box 30, needs to be lower than the ignition temperature of the
refrigerant used in the air-conditioning apparatus 100.
[0066] Accordingly, in order to appropriately detect the temperature of the wide bandgap
semiconductor 32, the temperature detecting means 34 may preferably be in contact
with the surface of the wide bandgap semiconductor 32. By appropriately detecting
the temperature of the wide bandgap semiconductor 32, it is possible to efficiently
suppress temperature increase of the wide bandgap semiconductor 32. For example, the
temperature detecting means 34 may be attached to the surface of the wide bandgap
semiconductor 32 with a thermal conductive adhesive such that the two can be placed
in contact with each other. Alternatively, as shown in Fig. 9, the temperature detecting
means 34 and the wide bandgap semiconductor 32 can be placed in contact with each
other using an attachment 35 and fixtures 36.
[0067] Note that a thermistor may preferably be used as the temperature detecting means
34. Alternatively, other temperature sensors such as a thermocouple may be used as
the temperature detecting means 34. The material, shape, size, and the number of attachments
35 and fixtures 36 are not limited to those illustrated in Fig. 9, and any configuration
may be employed as long as the wide bandgap semiconductor 32 and the temperature detecting
means 34 can be placed in contact with each other.
[0068] An operation of suppressing temperature increase of the wide bandgap semiconductor
32 will be described. When the temperature detecting means 34 detects that the surface
temperature of the wide bandgap semiconductor 32 is equal to a predetermined temperature,
the controller 50 stops the operation of the air-conditioning apparatus 100. Alternatively,
the controller 50 reduces the rotation speed of the compressor 1. This control operation
makes it possible to suppress further heat generation in the wide bandgap semiconductor
32, and thus to suppress temperature increase of the wide bandgap semiconductor 32.
[0069] In the case where the heating temperature of the wide bandgap semiconductor 32 does
not decrease less than the predetermined temperature even though this control operation
is performed, the controller 50 completely stops the air-conditioning apparatus 100.
That is, when the temperature of the wide bandgap semiconductor 32 reaches the predetermined
temperature (suppression control start temperature) used as a condition for starting
suppression control of temperature increase of the wide bandgap semiconductor 32,
the controller 50 performs control for suppressing temperature increase of the wide
bandgap semiconductor 32. By performing this control operation, it is possible to
reduce the risk in the event of refrigerant leakage, and thus to provide an air-conditioning
apparatus 100 with significantly improved safety. Note that, in the case where this
control operation is performed, this information may preferably be notified by sound
or display.
[0070] Next, a description will be given of the predetermined temperature (suppression control
start temperature). The suppression control start temperature as the predetermined
temperature used as a condition for starting suppression control of temperature increase
of the wide bandgap semiconductor 32 needs to be determined in view of variation in
a thermistor, variation in mounting of the thermistor on the wide bandgap semiconductor,
and the like. Further, the ignition temperature of refrigerant varies in accordance
with the humidity and temperature around the refrigerant. That is, if the predetermined
temperature is set to be equal to the ignition temperature, the suppression control
of temperature increase of the wide bandgap semiconductor 32 may or may not be performed
depending on the conditions.
[0071] Accordingly, the predetermined temperature needs to be set with a very large margin.
For this reason, in the case of the air-conditioning apparatus 100, the predetermined
temperature is set to be "around the ignition temperature of refrigerant to be used
- 100 degrees C" in view of various environmental influences, aging degradation, individual
differences and the like. Although the predetermined temperature may be changed in
accordance with a refrigerant to be used, the predetermined temperature may preferably
be set using HFO1234ze(E) having the lowest ignition temperature among the refrigerants
of Table 2 as a reference, in view of versatility. In this case, the predetermined
temperature is about 188 degrees C.
[0072] Further, although the wide bandgap semiconductor 32 is excel in heat resistance,
the risk of failure increases when the temperature is 200 degrees C or higher. Accordingly,
in order to ensure the safety and to ensure the reliability of the wide bandgap semiconductor
32, the predetermined temperature is set to around 150 degrees C. Thus, the safety
is ensured, and the reliability of the wide bandgap semiconductor 32 is also ensured.
Hence, the reliability of the air-conditioning apparatus 100 is significantly enhanced.
[0073] As described above, in the outdoor unit 10 according to Embodiment, the installation
position of the electrical component box 30 is specified. Therefore, even if a flammable
refrigerant leaks, it is possible to significantly suppress entry of the leaked refrigerant
into the electrical component box 30. Therefore, according to the outdoor unit 10
of Embodiment, it is possible to significantly improve the safety. Further, according
to the outdoor unit 10 of Embodiment, since the wide bandgap semiconductor 32 is used
as a part of the inverter substrate 31, it is possible to provide excellent heat resistance
and to ensure high reliability. Further, the air-conditioning apparatus 100 of Embodiment
includes the outdoor unit 10. Therefore, similar to the outdoor unit 10, the safety
and reliability thereof are significantly improved.
Reference Signs List
[0074] 1 compressor 2 oil separator 3 flow switching device 4 heat-source-side heat exchanger
5 accumulator 6 supercooling heat exchanger 7 expansion device 8 oil return circuit
8a pressure reducing means 9 opening and closing valve 10 outdoor unit 10a housing
11 opening and closing valve 12 bypass 20 indoor unit 20a indoor unit 20b indoor unit
20c indoor unit 20d indoor unit 21 expansion device 21a expansion device 21b expansion
device 21c expansion device 21d expansion device 22 use-side heat exchanger 22a use-side
heat exchanger 22b use-side heat exchanger 22c use-side heat exchanger 22d use-side
heat exchanger 30 electrical component box 31 inverter substrate 32 wide bandgap semiconductor
33a relay 33b relay 33c relay 33d relay 34 temperature detecting means 35 attachment
36 fixture40 front panel 41 air inlet 42 air outlet 43 pipe outlet 44 outdoor air-sending
device 50 controller 51 three-phase AC power supply 52 rectifier 53 reactor 54 smoothing
capacitor 55 inverter main circuit 56 control circuit 57 motor 100 air-conditioning
apparatus
1. A n outdoor unit (10) constituting part of an air-conditioning apparatus (100) using
a flammable refrigerant, the outdoor unit (10) comprising:
a housing (10a);
a compressor (1) disposed inside the housing (10a) and configured to compress a refrigerant;
a heat-source-side heat exchanger (4) disposed along a part of an inner wall of the
housing (10a), and into which the refrigerant discharged from the compressor (1) or
the refrigerant that is to be suctioned into the compressor (1) flows;
an outdoor air-sending device (44) disposed on a top of the housing (10a) and configured
to form an air flow inside the housing (10a);
a controller (50) configured to control the compressor (1) and the outdoor air-sending
device (44); and
an electrical component box (30) disposed in the housing (10a) and configured to accommodate
at least the controller (50) and an electrical component used for controlling a drive
unit included in the air-conditioning apparatus (100),
wherein the electrical component box (30) is disposed such that a bottom surface of
the electrical component box (30) is located at a height greater than 1/3 a height
of the housing (10a) from a bottom surface of the housing (10a), and
wherein the controller (50) and the electrical component are disposed such that bottom
surfaces thereof are located at a height greater than 1/3 a height of the electrical
component box (30) from the bottom surface of the electrical component box (30).
2. The outdoor unit (10) of claim 1, wherein at least a part of devices included in the
controller (50) is made of a wide bandgap semiconductor.
3. The outdoor unit (10) of claim 2, further comprising
temperature detecting means (34) configured to detect a temperature of the wide bandgap
semiconductor,
wherein the temperature detecting means (34) is disposed so as to be in contact with
a surface of the wide bandgap semiconductor.
4. The outdoor unit (10) of claim 3, wherein when the temperature detecting means (34)
detects that a detected temperature detected by the temperature detecting means (34)
reaches a predetermined temperature set in advance, the controller (50) stops operation
of the air-conditioning apparatus (100).
5. The outdoor unit (10) of claim 3, wherein when the temperature detecting means (34)
detects a predetermined temperature set in advance, the controller (50) reduces a
rotation speed of the compressor (1) to be lower than a current rotation speed.
6. The outdoor unit (10) of claim 5, wherein when the temperature of the wide bandgap
semiconductor is not lower than the predetermined temperature after a predetermined
time period elapses, the controller (50) stops operation of the air-conditioning apparatus
(100).
7. The outdoor unit (10) of any one of claims 4 to 6, wherein the predetermined temperature
is set at 150 degrees C or higher.
8. The outdoor unit (10) of any one of claims 2 to 7, wherein the wide bandgap semiconductor
is made of at least one of a silicon carbide device, a gallium nitride device, and
a diamond device.
9. The outdoor unit (10) of any one of claims 1 to 8, wherein R32 is used as the flammable
refrigerant.
10. The outdoor unit (10) of any one of claims 1 to 8, wherein HFO1234yf is used as the
flammable refrigerant.
11. The outdoor unit (10) of any one of claims 1 to 8, wherein HFO1234ze(E) is used as
the flammable refrigerant.
12. The outdoor unit (10) of any one of claims 1 to 8, wherein a refrigerant mixture of
R32 and HFO1234yf is used as the flammable refrigerant.
13. The outdoor unit (10) of any one of claims 1 to 8, wherein a refrigerant mixture of
R32 and HFO1234ze(E) is used as the flammable refrigerant.
14. An air-conditioning apparatus (100) comprising:
the outdoor unit (10) of any one of claims 1 to 13; and
an indoor unit (20) including a use-side heat exchanger (22) and connected to the
outdoor unit (10) with a refrigerant pipe.
1. Außeneinheit (10), einen Teil einer Klimaanlage (100) bildend, ein entzündlichen Kältemittel
verwendend, wobei die Außeneinheit umfasst:
ein Gehäuse (10a);
einen Verdichter (1), der in dem Gehäuse (10a) angeordnet ist und eingerichtet ist,
ein Kältemittel zu verdichten;
einen wärmequellenseitigen Wärmetauscher (4), der entlang eines Teils einer Innenwand
des Gehäuses (10a) angeordnet ist und in den das vom Verdichter (1) abgeführte Kältemittel
oder das Kältemittel, das in den Verdichter (1) gesaugt werden soll, fließt;
eine Außen-Luftsendeeinrichtung (44), die auf dem Gehäuse (10a) angeordnet ist und
eingerichtet ist, eine Luftströmung im Gehäuse (10a) auszubilden;
eine Steuerung (50), die eingerichtet ist, den Verdichter (1) und die Außen-Luftsendeeinrichtung
(44) zu steuern; und
eine Elektrische-Bauteile-Box (30), die im Gehäuse (10a) angeordnet ist und eingerichtet
ist, zumindest die Steuerung (50) und ein elektrisches Bauteil, das zum Steuern einer
in der Klimaanlage (100) enthaltenen Antriebseinheit verwendet wird, unterzubringen,
wobei die Elektrische-Bauteile-Box (30) so angeordnet ist, dass eine Bodenfläche der
Elektrische-Bauteile-Box (30) auf einer Höhe größer als 1/3 einer Höhe des Gehäuses
(10a) von der Bodenfläche des Gehäuses (10a) aus positioniert ist, und
wobei die Steuerung (50) und das elektrische Bauteil so angeordnet sind, dass Bodenflächen
davon auf einer Höhe größer als 1/3 einer Höhe der Elektrische-Bauteile-Box (30) von
der Bodenfläche der Elektrische-Bauteile-Box (30) aus positioniert sind.
2. Außeneinheit (10) nach Anspruch 1, wobei zumindest ein Teil von in der Steuerung (50)
enthaltenen Einrichtungen aus einem Halbleiter mit großem Bandabstand hergestellt
ist.
3. Außeneinheit (10) nach Anspruch 2, ferner umfassend
Temperaturerfassungsmittel (34), das eingerichtet ist, eine Temperatur des Halbleiters
mit großem Bandabstand zu erfassen,
wobei das Temperaturerfassungsmittel (34) angeordnet ist, um in Kontakt mit einer
Oberfläche des Halbleiters mit großem Bandabstand zu stehen.
4. Außeneinheit (10) nach Anspruch 3, wobei die Steuerung (50), wenn das Temperaturerfassungsmittel
(34) erfasst, dass eine durch das Temperaturerfassungsmittel (34) erfasste Temperatur
eine im Vorhinein eingestellte vorbestimmte Temperatur erreicht, den Betrieb der Klimaanlage
(100) stoppt.
5. Außeneinheit (10) nach Anspruch 3, wobei die Steuerung (50), wenn das Temperaturerfassungsmittel
(34) eine im Vorhinein eingestellte vorbestimmte Temperatur erfasst, eine Drehzahl
des Verdichters (1) reduziert, um niedriger als eine aktuelle Drehzahl zu sein.
6. Außeneinheit (10) nach Anspruch 5, wobei die Steuerung (50), wenn die Temperatur des
Halbleiters mit großer Bandbreite nach Ablauf einer vorbestimmten Zeitspanne nicht
niedriger ist als die vorbestimmte Temperatur, den Betrieb der Klimaanlage (100) stoppt.
7. Außeneinheit (10) nach einem der Ansprüche 4 bis 6, wobei die vorbestimmte Temperatur
auf 150 Grad C oder höher eingestellt ist.
8. Außeneinheit (10) nach einem der Ansprüche 2 bis 7, wobei der Halbleiter mit großer
Bandbreite zumindest aus einem einer Siliziumcarbideinrichtung, einer Galliumnitrideinrichtung
und einer Diamanteinrichtung hergestellt ist.
9. Außeneinheit (10) nach einem der Ansprüche 1 bis 8, wobei R32 als das entzündliche
Kältemittel verwendet wird.
10. Außeneinheit (10) nach einem der Ansprüche 1 bis 8, wobei HFO1234yf als das entzündliche
Kältemittel verwendet wird.
11. Außeneinheit (10) nach einem der Ansprüche 1 bis 8, wobei HFO1234ze(E) als das entzündliche
Kältemittel verwendet wird.
12. Außeneinheit (10) nach einem der Ansprüche 1 bis 8, wobei eine Kältemittelmischung
aus R32 und HFO1234yf als das entzündliche Kältemittel verwendet wird.
13. Außeneinheit (10) nach einem der Ansprüche 1 bis 8, wobei eine Kältemittelmischung
aus R32 und HFO1234ze(E) als das entzündliche Kältemittel verwendet wird.
14. Klimaanlage (100), umfassend:
die Außeneinheit (10) nach einem der Ansprüche 1 bis 13; und
eine Inneneinheit (20), umfassend einen nutzungsseitigen Wärmetauscher (22) und über
eine Kältemittelleitung mit der Außeneinheit (10) verbunden.
1. Unité extérieure (10) constituant une partie d'un appareil de climatisation (100)
utilisant un fluide frigorigène inflammable, l'unité extérieure (10) comprenant :
un logement (10a) ;
un compresseur (1) disposé à l'intérieur du logement (10a) et configuré pour comprimer
un fluide frigorigène ;
un échangeur de chaleur côté source de chaleur (4) disposé le long d'une partie d'une
paroi interne du logement (10a), et dans lequel le fluide frigorigène déchargé du
compresseur (1) ou le fluide frigorigène qui doit être aspiré dans le compresseur
(1) s'écoule ;
un dispositif d'envoi d'air extérieur (44) disposé sur le dessus du logement (10a)
et configuré pour former un écoulement d'air à l'intérieur du logement (10a) ;
un contrôleur (50) configuré pour commander le compresseur (1) et le dispositif d'envoi
d'air extérieur (44) ; et
un boîtier de composants électriques (30) disposé dans le logement (10a) et configuré
pour loger au moins le contrôleur (50) et un composant électrique utilisé pour commander
une unité de commande incluse dans l'appareil de climatisation (100),
dans laquelle le boîtier de composants électriques (30) est disposé de sorte qu'une
surface inférieure du boîtier de composants électriques (30) soit située à une hauteur
supérieure à 1/3 d'une hauteur du logement (10a) à partir d'une surface inférieure
du logement (10a), et
dans laquelle le contrôleur (50) et le composant électrique sont disposés de sorte
que les surfaces inférieures de ceux-ci soient situées à une hauteur supérieure à
1/3 d'une hauteur du boîtier de composants électriques (30) à partir de la surface
inférieure du boîtier de composants électriques (30).
2. Unité extérieure (10) selon la revendication 1, dans laquelle au moins une partie
des dispositifs inclus dans le contrôleur (50) est constituée d'un semi-conducteur
à large bande interdite.
3. Unité extérieure (10) selon la revendication 2, comprenant en outre :
des moyens de détection de température (34) configurés pour détecter une température
du semi-conducteur à large bande interdite,
dans laquelle les moyens de détection de température (34) sont disposés de manière
à être en contact avec une surface du semi-conducteur à large bande interdite.
4. Unité extérieure (10) selon la revendication 3, dans laquelle, lorsque les moyens
de détection de température (34) détectent qu'une température détectée qui est détectée
par les moyens de détection de température (34) atteint une température prédéterminée
établie à l'avance, le contrôleur (50) arrête le fonctionnement de l'appareil de climatisation
(100).
5. Unité extérieure (10) selon la revendication 3, dans laquelle, lorsque les moyens
de détection de température (34) détectent une température prédéterminée établie à
l'avance, le contrôleur (50) réduit une vitesse de rotation du compresseur (1) à une
valeur inférieure à une vitesse de rotation actuelle.
6. Unité extérieure (10) selon la revendication 5, dans laquelle, lorsque la température
du semi-conducteur à large bande interdite n'est pas inférieure à la température prédéterminée
après qu'une période de temps prédéterminée s'est écoulée, le contrôleur (50) arrête
le fonctionnement de l'appareil de climatisation (100).
7. Unité extérieure (10) selon l'une quelconque des revendications 4 à 6, dans laquelle
la température prédéterminée est établie à 150 °C ou plus.
8. Unité extérieure (10) selon l'une quelconque des revendications 2 à 7, dans laquelle
le semi-conducteur à large bande interdite est constitué d'au moins l'un d'un dispositif
au carbure de silicium, d'un dispositif au nitrure de gallium et d'un dispositif au
diamant.
9. Unité extérieure (10) selon l'une quelconque des revendications 1 à 8, dans laquelle
du R32 est utilisé en tant que fluide frigorigène inflammable.
10. Unité extérieure (10) selon l'une quelconque des revendications 1 à 8, dans laquelle
du HFO1234yf est utilisé en tant que fluide frigorigène inflammable.
11. Unité extérieure (10) selon l'une quelconque des revendications 1 à 8, dans laquelle
du HFO1234ze(E) est utilisé en tant que fluide frigorigène inflammable.
12. Unité extérieure (10) selon l'une quelconque des revendications 1 à 8, dans laquelle
un mélange de fluide frigorigène de R32 et de HFO1234yf est utilisé en tant que fluide
frigorigène inflammable.
13. Unité extérieure (10) selon l'une quelconque des revendications 1 à 8, dans laquelle
un mélange de fluide frigorigène de R32 et de HFO1234ze(E) est utilisé en tant que
fluide frigorigène inflammable.
14. Appareil de climatisation (100) comprenant :
l'unité extérieure (10) selon l'une quelconque des revendications 1 à 13 ; et
une unité intérieure (20) comprenant un échangeur de chaleur côté utilisation (22)
et reliée à l'unité extérieure (10) par un tuyau de fluide frigorigène.