{DESCRIPTION}
{Title of Invention} CONTROL DEVICE AND SYSTEM, AND METHOD OF
CONTROLLING THE SAME
{Technical Field}
{0001}
The present invention relates to a control device and
system, and a method of controlling the same.
{Background Art}
{0002}
Conventionally, for example, a multi-type air
conditioning system is known in which one outdoor device and a
plurality of indoor devices are connected (see PTL 1, for
example). In such a multi-type air conditioning system, the
outdoor device has an outdoor device controlling unit and each
indoor device has an indoor device controlling unit for
intercommunication between the outdoor device controlling unit
and the indoor device controlling unit, so that the multi-type
air conditioning system can be entirely controlled.
{Citation List}
{Patent Literature}
{0003}
{PTL 1}
Japanese Unexamined Patent Application, Publication No.
2009-186144
{Summary of Invention}
3
{Technical Problem}
{0004}
In such a conventional air conditioning system capable of
performing air conditioning through intercommunication between
each indoor device controlling unit and the outdoor device
controlling unit, all the control programs used for system
control need to operate with the same control version, i.e.
interchangeability ensured between communication protocols or
control command systems. Hence, if the indoor device or
outdoor device constituting the air conditioning system is
partly changed to an apparatus with novel control specs, the
parts with original specs may operate but novel functional
parts are difficult to use.
{0005}
The applicant proposes development of a novel air
conditioning system in which an outdoor device controlling
unit and an indoor device controlling unit are separated from
the outdoor device including the outdoor device controlling
unit (local controlling unit) and an outdoor device control
target apparatus (actuator) and an indoor device including the
indoor device controlling unit (local controlling unit) and an
indoor device control target apparatus (actuator),
respectively, and these control functions are collected into
one control device.
{0006}
4
In this novel air conditioning system, a control device,
which has collected functions of the outdoor device
controlling unit and the indoor device controlling unit, sends
control commands to control target apparatuses (actuators) of
the outdoor device and the indoor device via a network. When
the outdoor device and the indoor device are controlled via a
network in this manner, the risk of troubles in control is low
in a place where a stable communication quality is provided,
and when the outdoor device and the indoor device are provided
in a place where the communication environment is unstable,
the communication quality decreases or interruption occurs,
which may cause an uncontrollable state.
{0007}
An object of the present invention is to provide a
control device and a system, and a method of controlling the
same which allow continuous stable control even when the
communication environment and other installation environments
change, for a system in which an apparatus is controlled via a
communication line like in the novel air conditioning system
described above.
{Solution to Problem}
{0008}
A first aspect of the present invention is a control
device that is connected to an apparatus including a local
controlling unit (e.g., all or part of the function of the
5
local controlling unit) via a communication line and that can
control the apparatus via the communication line, the control
device including: a control ratio changing means that changes
a control ratio (e.g., a ratio between control of the
corresponding actuator executed by the local controlling unit
and control of the actuator executed by the control device)
with respect to the local controlling unit, the control ratio
changing means including: a storage means that contains a
plurality of control modes with different control ratios, a
mode selecting means that selects one control mode from the
plurality of control modes in accordance with predetermined
conditions, and a mode notifying means that notifies the
apparatus of the control mode selected by the mode selecting
means.
{0009}
This control device can change the control ratio between
the local controlling unit and the control device in
accordance with installation environments and the like. Thus,
stable control can be achieved.
{0010}
In this control device, a communication quality
monitoring means that monitors a communication quality with
respect to the apparatus may be further included. The storage
means may contain the control modes associated with
communication quality information, and the mode selecting
6
means may refer to information stored in the storage means and
select a control mode corresponding to the current
communication quality information.
{0011}
In this control device, the communication quality
monitoring means monitors the communication quality with
respect to the apparatus, and a control mode corresponding to
this communication quality is selected by the mode selecting
means. Accordingly, when apparatus control is executed via
the communication line, the control by the control device can
be reduced upon a reduction in communication quality, for
example. Hence, even if a reduction in communication quality
or interruption occurs, the local controlling unit performs
apparatus control, so that apparatus control can be continued,
for example.
{0012}
In this control device, if the control mode selected by
the mode selecting means is different from the previously
selected control mode, the previous control mode may be
continued for a predetermined period of time and a request for
a reduction in transmission data volume may be sent to the
apparatus.
{0013}
Since a request for a reduction in transmission data
volume is sent to the apparatus before the control mode is
7
switched, data required for control can be obtained even if
the communication quality decreases to a certain level.
Accordingly, if the communication quality fluctuates in a
short cycle, the control mode can be prevented from frequently
switching, for example. Further, even if the communication
quality temporarily decreases, reducing the transmission data
volume allows data required for control to be obtained.
{0014}
In this control device, if the communication quality is
at or above a predetermined threshold, the latest control
program may be sent to the apparatus.
{0015}
When the communication quality is excellent, the latest
control program is sent to the apparatus, so that the control
programs in the local controlling unit of the apparatus can be
readily updated.
{0016}
In this control device, the mode selecting means may hold
scheduling information associated with time and a control mode
and a control mode may be selected according to the scheduling
information.
{0017}
In this control device, the mode selecting means selects
a mode in accordance with schedule information associated with
time and a control mode.
8
{0018}
In this control device, upon reception of information on
a control mode from the local controlling unit, the mode
selecting means may select the received control mode.
{0019}
In this control device, a control mode is selected based
on information from the local controlling unit.
{0020}
In this control device, the control mode may include a
full remote control mode in which the control device performs
control, a full local control mode in which only the local
controlling unit performs control, and at least one of a
protection control mode in which only protection control is
performed by the local controlling unit, a target value
instruction control mode in which a control target value is
given to the apparatus and control based on the control target
value is performed by the local controlling unit, and a remote
monitoring mode in which the state value of the apparatus is
monitored.
{0021}
Since a plurality of control modes for different stages
of control ratios are prepared, control by the control device
can be performed on a priority basis as much as possible and a
control mode suitable for the communication quality can be
selected.
9
{0022}
In this control device, for current data that is
contained in a packet travelling between the apparatus and the
control device and is the same as data sent in the previous
transmission period, not the current data but information
indicating that the current data is the same as the data in
the previous transmission period may be stored in the packet.
{0023}
This can effectively reduce data volume.
{0024}
A second aspect of the present invention is an apparatus
that is connectable to the above-described control device via
a communication line, the apparatus including: a storage means
that contains a plurality of control modes; and a local
controlling unit that executes, upon reception of information
on a control mode from the control device, control in the
received control mode.
{0025}
A third aspect of the present invention is a system
including: the above-described control device; and the abovedescribed
apparatus.
{0026}
In this system, a plurality of apparatuses may be further
included. When communication between any one of the
apparatuses and the control device is interrupted and
10
communication between any other one of the apparatuses and the
control device is established, control information for the one
of the apparatuses may be sent to the one of the apparatuses
via the other one of the apparatuses.
{0027}
In this system, even if interruption of communication
between the control device and any of the apparatuses occurs,
control information from the control device can be sent via
the other one of the apparatuses still in communication with
the control device. Accordingly, even if the communication
quality decreases, control by the control device can be
achieved.
{0028}
In this system, the plurality of apparatuses are a
plurality of indoor devices, a plurality of outdoor devices,
or an outdoor device and an indoor device, for example.
{0029}
A fourth aspect of the present invention is a method of
controlling a system including an apparatus with a local
controlling unit and a control device that can control the
apparatus via a communication line. Cooperation between the
local controlling unit and the control device can execute
control of the apparatus, and a control ratio between the
controlling unit and the control device is dynamically changed
according to the communication quality with respect to the
11
apparatus.
{Advantageous Effect of Invention}
{0030}
The present invention provides an advantage of a
reduction in influence on control for an impaired
communication quality or interruption.
{Brief Description of Drawings}
{0031}
{Fig. 1} Fig. 1 illustrates a refrigerant system in an air
conditioning system according to one embodiment of the present
invention.
{Fig. 2} Fig. 2 illustrates an electrical configuration of the
air conditioning system according to one embodiment of the
present invention.
{Fig. 3} Fig. 3 is a functional block diagram of the outdoor
device controlling unit shown in Fig. 2.
{Fig. 4} Fig. 4 is a functional block diagram of the indoor
device controlling unit shown in Fig. 2.
{Fig. 5} Fig. 5 is a functional block diagram of a control
device according to one embodiment of the present invention.
{Fig. 6} Fig. 6 illustrates an example of information stored
in the storage shown in Fig. 5.
{Fig. 7} Fig. 7 illustrates an example of a packet structure
used in the air conditioning system according to one
embodiment of the present invention.
12
{Fig. 8} Fig. 8 illustrates an example of a packet structure
used in the air conditioning system according to one
embodiment of the present invention.
{Description of Embodiment}
{0032}
One embodiment of use of a control device and system, and
a method of controlling the same of the present invention in
an air conditioning system will now be described with
reference to the drawings. Here, a control device and other
devices of the present invention may be widely applied to any
system other than the air conditioning system described below,
which remotely controls an apparatus via a communication line.
An example of the apparatus is a machine tool.
{0033}
As shown in Fig. 2, an air conditioning system 1
according to one embodiment of the present invention includes,
for example, an outdoor device 10, an indoor device 20, and a
control device 3. The outdoor device 10 includes an outdoor
device controlling unit (local controlling unit) 13 for
locally controlling the outdoor device 10, while the indoor
device 20 includes an indoor device controlling unit (local
controlling unit) 23 for locally controlling the indoor device
20, respectively.
{0034}
The outdoor device 10 and the indoor device 20 are
13
connected to the control device 3 via a communication line 6
such that the control device 3 can remotely control them.
That is, the control device 3 has the same functions as the
outdoor device controlling unit 13 and the indoor device
controlling unit 23, and can send control commands to the
outdoor device 10 and the indoor device 20 via the
communication line 6. In addition, the air conditioning
system 1 according to this embodiment is mainly characterized
in that it dynamically changes the control ratio between the
control device 3, the outdoor device controlling unit 13, and
the indoor device controlling unit 23, in accordance with the
communication quality of the communication line 6.
The air conditioning system 1 according to this
embodiment will now be described in detail.
{0035}
Fig. 1 illustrates a refrigerant circuit in the air
conditioning system 1 according to one embodiment of the
present invention. As shown in Fig. 1, the air conditioning
system 1 includes an outdoor device 10 and an indoor device 20
which is connected through a refrigerant pipe 28 shared with
the outdoor device 10. Although Fig. 1 illustrates, for
convenience, the case where one outdoor device 10 and one
indoor device 20 constitute the air conditioning system 1, the
number of outdoor devices 10 and indoor devices 20
constituting the air conditioning system 1 is not limited to
14
this example.
{0036}
As shown in Fig. 1, the outdoor device 10 includes, for
example, a compressor 15 that compresses and ejects a
refrigerant, a four-way valve 16 that changes the direction of
the circulation of the refrigerant, an outdoor heat exchanger
17 that performs heat exchange between the refrigerant and
outside air, an outdoor fan 18, and an accumulator 19 that is
provided on the inlet pipe of the compressor 15 to separate
liquid of the refrigerant. The outdoor device 10 includes
various sensors 11 (see Fig. 2) such as a pressure sensor 11a
for measuring low pressure, a pressure sensor 11b for
measuring high pressure, and a temperature sensor 11c for
measuring the temperature of the outdoor heat exchanger 17.
{0037}
The indoor device 20 includes an electron expansion valve
25, an indoor heat exchanger 26, and an indoor fan 27. The
indoor device 20 includes various sensors 21 (see Fig. 2) such
as a pressure sensor 21a for measuring the pressure across the
expansion valve, and a temperature sensor 21b for measuring
the temperature of the indoor heat exchanger 26.
{0038}
Fig. 2 illustrates an electrical configuration of the air
conditioning system 1 according to this embodiment. As shown
in Fig. 2, intercommunication between the outdoor device 10
15
and the indoor device 20 can be provided via the communication
line 6. The control device 3 can be connected to the
communication line 6 to provide intercommunication between the
outdoor device 10 and the indoor device 20 via the
communication line 6. The communication line 6 is either
wired or wireless.
Here, intercommunication between the outdoor device 10
and the indoor device 20 may be provided via any communication
line other than the communication line 6.
{0039}
The outdoor device 10 includes various sensors 11
including the pressure sensors 11a and 11b and the temperature
sensor 11c, various drivers 12 for controlling various
apparatus elements (e.g., the compressor 15 and the outdoor
fan 18) constituting the outdoor device 10, an outdoor device
controlling unit 13 for controlling various apparatus elements
(e.g., the compressor 15) included in the outdoor device 10,
and a communication unit 14 for communication via the
communication line 6.
{0040}
The indoor device 20 includes various sensors 21
including the pressure sensor 21a and the temperature sensor
21b, various drivers 22 for controlling various apparatus
elements (e.g., the electron expansion valve 25 and the indoor
fan 27) constituting the indoor device 20, an indoor device
16
controlling unit 23 for controlling various apparatus elements
(e.g., the electron expansion valve 25 and the indoor fan 27)
included in the indoor device 20, and a communication unit 24
for communication via the communication line 6.
{0041}
The outdoor device controlling unit 13 and the indoor
device controlling unit 23 are computers including a
processor, such as a CPU, a main memory, such as a RAM, and a
rewritable memory, such as a hard disc. The processor expands
various programs (e.g., programs for the control modes
described later), which are written on hard discs and the
like, in the main memory and processes them to achieve the
functions of the parts described later.
{0042}
Fig. 3 is a functional block diagram of the outdoor
device controlling unit 13. As shown in Fig. 3, the outdoor
device controlling unit 13 includes an input/output unit 41, a
storage 42, a mode selector 43, and a control running unit 44.
The storage 42 contains information for different control
modes in order to control the outdoor device 10 in different
control modes. The storage 42 contains, for example,
information on the full remote control mode, the protection
control mode, the target value instruction control mode, the
remote monitoring mode, and the full local control mode.
{0043}
17
In the full remote control mode, a control command from
the control device 3 described later is received, and the
received control command controls the apparatuses in the
outdoor device (e.g., the compressor 15, the four-way valve
16, and the outdoor fan 18). In other words, in the full
remote control mode, the controlling unit 13 does not perform
computation for control.
{0044}
In the protection control mode, the apparatuses in the
outdoor device are controlled by a control command from the
control device 3, but emergency stop control and protection
control are performed by the outdoor device controlling unit
13. Emergency stop control refers to detecting
irregularities, for example, if the low pressure is at or
below a predetermined lower threshold or if the high pressure
is at or above a predetermined upper threshold, and stopping
the compressor 15. Protection control refers to decreasing
the RPM of the compressor to prevent emergency stop control as
much as possible if the tendency of an irregularity is
detected. For example, if the low pressure is below a
protection threshold which is set greater than the lower
threshold or if the high pressure is at or above a protection
threshold which is set lower than the upper threshold, the RPM
of the compressor 15 is decreased.
{0045}
18
In the target value instruction control mode, the control
device 3 produces a control target value and the outdoor
device controlling unit 13 performs computation of the control
commands for the apparatuses on the basis of the produced
control target value; thus, the outdoor device controlling
unit 13 controls the apparatuses.
{0046}
In the remote monitoring mode, the outdoor device
controlling unit 13 controls the apparatuses, and when any
irregularity or failure is detected, information on such
irregularity detection or failure detection is sent to the
control device 3. Accordingly, in the remote monitoring mode,
only if any irregularity is detected, the outdoor device 10
sends a notice of an irregularity to the control device 3.
{0047}
In the full local control mode, all control is performed
by the outdoor device controlling unit 13. In other words, in
the full local control mode, control is performed when
intercommunication with the control device 3 via the
communication line 6 is impossible.
{0048}
As for the above-described control modes, the control
load on the outdoor device controlling unit 13 increases in
the full remote control mode, the protection control mode, the
target value instruction control mode, the remote monitoring
19
mode, and the full local control mode, in this order. In
other words, the full remote control mode causes the lowest
load on the outdoor device controlling unit 13 for processing,
while the full local control mode causes the highest load on
the outdoor device controlling unit 13 for processing.
{0049}
The mode selector 43 selects a designated control mode
when receiving information on the control mode from the
control device 3. While the full remote control mode, the
protection control mode, or the target value instruction
control mode is selected, the mode selector 43 switches the
mode to the full local control mode if no data is received
from the control device 3 for a predetermined continuous
period of time. Accordingly, when information sent via the
communication line 6 is suddenly interrupted, for example, the
mode can be readily switched to control by the outdoor device
controlling unit 13, thereby allowing continuous control of
the apparatus.
{0050}
The control running unit 44 reads information on the
control mode currently selected by the mode selector 43 from
the storage 42 and executes it.
{0051}
Fig. 4 is a functional block diagram of the indoor device
controlling unit 23. As shown in Fig. 4, the indoor device
20
controlling unit 23 includes the input/output unit 51, the
storage 52, the mode selector 53, and the control running unit
54. The storage 52 contains information for different control
modes in order to control the indoor device in different
control modes. In other words, items to be processed executed
by the indoor device controlling unit 23 in the full remote
control mode, the protection control mode, the target value
instruction control mode, the remote monitoring mode, and the
full local control mode are stored in the storage 52.
{0052}
Upon reception of information on the control mode from
the control device 3, the mode selector 53 selects the
designated control mode. While the full remote control mode,
the protection control mode, or the target value instruction
control mode is selected, the mode selector 53 switches the
mode to the full local control mode if no data is received
from the control device 3 for a predetermined continuous
period of time. Accordingly, when information sent via the
communication line 6 is suddenly interrupted, for example, the
mode can be readily switched to control by the indoor device
controlling unit 23, thereby allowing continuous control of
the apparatus.
{0053}
The control running unit 54 reads information on the
control mode currently selected by the mode selector 53 from
21
the storage 52 and executes it.
{0054}
In all the above-described control modes, control of the
angles of the louver and flap (wind direction control) and
control of the RPM of the indoor fan (airflow control) may be
always performed by the indoor device controlling unit 23.
This is because these controls can be achieved by
intercommunication between the remote controller and the
indoor device controlling unit 23 and variations in these
control values have almost no impact on the refrigerant pipe
28.
{0055}
Like the outdoor device controlling unit 13 and the
indoor device controlling unit 23, the control device 3
includes a computer including a processor, such as a CPU, a
main memory, such as a RAM, and a rewritable memory, such as a
hard disc. The processor expands various programs (e.g.,
programs for the control modes described later), which are
written on hard discs and the like, in the main memory and
processes them to achieve the functions of the parts described
later.
{0056}
Fig. 5 is a functional block diagram of the control
device 3. As shown in Fig. 5, the control device 3 includes a
communication unit 31, a communication quality monitoring unit
22
32, a control ratio changing unit 33, an outdoor device
controlling unit 35, and an indoor device controlling unit 36.
{0057}
The communication unit 31 provides intercommunication
between the outdoor device 10 and the indoor device 20 via the
communication line 6. The communication quality monitoring
unit 32 monitors the communication quality of the
communication line 6. For example, when data volume that
should be usually received in a predetermined period of time
(hereinafter referred to as "total data volume") is
predetermined, the data volume received in the predetermined
period of time is divided by the total data volume to
determine the quality evaluation value, and this quality
evaluation value is sent to the control ratio changing unit
33.
{0058}
The control ratio changing unit 33 dynamically changes
the control ratio between the control device 3 and the local
controlling units: the outdoor device controlling unit 13 and
the indoor device controlling unit 23, in accordance with the
communication quality of the communication line 6. The
control ratio changing unit 33 includes, for example, the
storage 61, the mode selector 62, and the mode notifying unit
63.
{0059}
23
As shown in Fig. 6, the storage 61 contains, for example,
quality evaluation values (communication quality information)
associated with the respective control modes.
{0060}
The mode selector 62 selects a control mode corresponding
to the current quality evaluation value on the basis of the
quality evaluation values from the communication quality
monitoring unit 32 and information stored in the storage 61.
{0061}
The mode notifying unit 63 notifies the outdoor device 10
and the indoor device 20 of the selected control mode via the
communication unit 31 and also notifies the outdoor device
controlling unit 35 and the indoor device controlling unit 36
in the control device 3 of the selected control mode.
{0062}
Information can be shared between the outdoor device
controlling unit 35 and the indoor device controlling unit 36.
{0063}
The outdoor device controlling unit 35 includes an
input/output unit 71, a storage 72, and a control running unit
73.
{0064}
The input/output unit 71 receives values measured by
various sensors and information on the states of the
apparatuses sent from the outdoor device 10. The storage 72
24
contains information for different control modes in order to
control the outdoor device 10 in different control modes. In
other words, items to be processed (e.g., programs and data)
executed by the outdoor device controlling unit 35 in the
control device 3 in the full remote control mode, the
protection control mode, the target value instruction control
mode, the remote monitoring mode, and the full local control
mode are stored.
{0065}
For example, the items to be processed in the full remote
control mode are intended to be used such that the outdoor
device controlling unit 35 of the control device 3 remotely
controls the outdoor device 10. Here, the items to be
processed in the full remote control mode are not necessarily
the same as those of the outdoor device controlling unit 13 of
the outdoor device 10 in the full local control mode.
{0066}
For example, if distributed autonomous control is used in
which the outdoor device controlling unit 35 and the indoor
device controlling unit 36 of the control device 3 share
information and operate independently of each other, control
items used in distributed autonomous control are stored.
Here, in distributed autonomous control, information is
received from various sensors 11 and another controlling unit,
i.e., the indoor device controlling unit 36, and a
25
predetermined application inputs the information in accordance
with control rules and sends a control command to the outdoor
device 10.
{0067}
The protection control mode is the same as the full
remote control mode except that it omits protection control.
In the target value instruction control mode, processing
related to computation of target values is performed but
computation of control commands for the apparatuses based on
protection control and target values is omitted. For example,
in the target value instruction control mode, target values
that contribute to energy saving are computed and sent to the
outdoor device 10.
{0068}
In the remote monitoring mode, control of the apparatuses
is not performed and information on irregularities sent from
the outdoor device 10 is received. In the full local control
mode, no processing is performed.
{0069}
The control running unit 73 reads information on the
control mode, which is notified by the mode notifying unit 63,
from the storage 72 and executes it.
{0070}
Similarly, the indoor device controlling unit 36 includes
an input/output unit 81, a storage 82, and a control running
26
unit 83. The input/output unit 71 receives values measured by
various sensors and information on the states of the
apparatuses sent from the indoor device 20. The storage 82
contains information for different control modes in order to
control the indoor device 20 in different control modes.
{0071}
In other words, items to be processed executed by the
indoor device controlling unit 36 in the control device 3 in
the full remote control mode, the protection control mode, the
target value instruction control mode, the remote monitoring
mode, and the full local control mode are stored in the
storage 82.
{0072}
For example, the items to be processed in the full remote
control mode are the same as the items to be processed in the
full local control mode of the indoor device controlling unit
23 of the indoor device 20. The protection control mode is
the same as the full remote control mode except that it omits
protection control. In the target value instruction control
mode, processing related to computation of target values is
performed but computation of control commands for the
apparatuses based on protection control and target values is
omitted. In the remote monitoring mode, control of the
apparatuses is not performed and information on irregularities
sent from the indoor device 20 is received. In the full local
27
control mode, no processing is performed.
{0073}
The control running unit 83 reads information on the
control mode, which is notified by the mode notifying unit 63,
from the storage 82 and executes it.
{0074}
In the case where the angles of the flap and the louver
and the RPM of the indoor fan are all controlled by the indoor
device controlling unit 23 of the indoor device 20, that is,
in the case where all processing is done by the indoor device
20, the controls by the control device 3 are omitted.
{0075}
Here, the above-described control ratio changing unit 33,
outdoor device controlling unit 35, indoor device controlling
unit 36, and other units may be virtually mounted on one
hardware. For example, upon startup, a program on the master
boot record is run, a virtual CPU and virtual memory are
allocated to each unit, and each unit is then virtually
generated on one hardware.
{0076}
The operation of the air conditioning system 1 having the
above-described configuration will now be explained.
First, the outdoor device 10 and the indoor device 20
send measurement data and control information obtained by the
various sensors 11 and 21 to the control device 3 via the
28
communication line 6.
{0077}
These data are received by the communication unit 31 of
the control device 3, quality evaluation values are computed
by the communication quality monitoring unit 32 on the basis
of this received data volume, and the results are sent to the
mode selector 62 of the control ratio changing unit 33.
{0078}
The mode selector 62 selects a control mode corresponding
to the current quality evaluation value on the basis of the
information stored in the storage 61 and sends the selected
control mode to the mode notifying unit 63. The mode
notifying unit 63 notifies the outdoor device controlling unit
35 and the indoor device controlling unit 36 of the control
mode selected by the mode selector 62.
{0079}
In the outdoor device controlling unit 35, computation
corresponding to the control mode notified by the mode
notifying unit 63 is performed by the control running unit 73.
Hence, for example, when the full remote control mode is
selected, computation using sensor-measured values and the
like fed to the input/output unit 71 is performed to produce
control commands for the apparatuses in the outdoor device 10
(e.g., the compressor 15, the four-way valve 16, the outdoor
heat exchanger 17, and the outdoor fan 18).
29
{0080}
Similarly, in the indoor device controlling unit 36,
computation corresponding to the control mode notified by the
mode notifying unit 63 is performed by the control running
unit 83. Hence, for example, when the full remote control
mode is selected, computation using sensor-measured values and
the like fed to the input/output unit 81 is performed to
produce control commands for the apparatuses in the indoor
device 20 (e.g., the electron expansion valve 25 and the
indoor fan 27).
{0081}
Various control commands computed in this manner are sent
to the outdoor device 10 and the indoor device 20 via the
communication line 6. The outdoor device 10 and the indoor
device 20 receiving these control commands at the various
drivers 12 and 22 achieve control according to the control
commands.
{0082}
The above-described processing is repeated in a
predetermined cycle, and an appropriate control mode is
selected depending on the current communication quality. For
example, cooperation between the control device 3, the outdoor
device controlling unit 13, and the indoor device controlling
unit 23 achieves control of the air conditioning system 1.
{0083}
30
Consequently, for example, when the mode is switched from
the full remote control mode to the protection control mode
because the communication quality slightly decreases,
cooperation between the outdoor device controlling unit 35 in
the control device 3 and the outdoor device controlling unit
13 in the outdoor device 10 achieves control of the outdoor
device 10, and, similarly in the indoor device 20, cooperation
between the indoor device controlling unit 36 in the control
device 3 and the indoor device controlling unit 23 in the
indoor device 20 achieves control of the indoor device 20.
{0084}
As explained above, with the air conditioning system and
the method therefor and the control device according to this
embodiment, the control ratio between the local controlling
units: the outdoor device controlling unit 13 and the indoor
device controlling unit 23, and the control device 3 is
dynamically changed in accordance with the communication
quality. Hence, for example, even if the communication
quality decreases and information from the control device 3 is
interrupted under control by the control device 3 via the
communication line 6, switching to control by the local
controlling unit allows the outdoor device 10 and the indoor
device 20 to be continuously controlled. Since a plurality of
control modes are prepared for different control ratios, the
control ratio of the control device can be finely changed
31
according to the communication quality.
{0085}
Although this embodiment illustrates the case where the
communication quality monitoring unit 32 evaluates the
communication quality on the basis of the volume of data
received in a predetermined time, this is not necessarily the
case and the evaluation may be based on the communication
rate, for example. For the full remote control mode, whether
the control mode should be switched may be determined based on
whether minimum data required for control has been received.
{0086}
In the air conditioning system according to this
embodiment, after the mode selector 62 selects the control
mode according to the communication evaluation value, if the
selected control mode may be different from the current
control mode, the current communication mode is maintained for
a predetermined period of time, which means that the control
mode is not switched immediately and the data volume sent from
the outdoor device 10 and the indoor device 20 to the control
device 3 is reduced according to a reduction in communication
quality.
{0087}
A way of reducing data volume is to thin out slowresponse
data, that is, parameters which take a certain time
to change in value, e.g., temperature data (outside
32
temperature and room temperature (indoor suction temperature).
That is, the transmission frequency for temperature data is
reduced (e.g., 10 times of data transmission is changed to one
time transmission) to reduce the total data volume.
{0088}
Another way of reducing data volume is to add information
to the packet structure of the same data as data sent in the
previous transmission period such that the information
indicates these data are equivalent, which may make the total
packet data volume smaller.
{0089}
Fig. 7 illustrates an example packet structure. Fig.
7(a) illustrates a packet structure according to this
embodiment. In Fig. 7(a), DST is a destination address, SRC
is a source address, and Num is a data count. FLAG is an
equivalence data flag and a bit 1 is given if the data is the
same as in the previous transmission period, while a bit 0 is
given if the data is different. Data i refers to the i-th
data, and SUM is a checksum.
{0090}
Fig. 7(b) illustrates a specific packet structure based
on Fig. 7(a) in which the data count is 4 and FLAG is
"00000000 B(00 H)", and Fig. 7(c) illustrates a specific
packet structure based on Fig. 7(a) in which the data count is
8 and FLAG is "00001111 B(0F H)". As shown in Fig. 7(c), data
33
1 to 4 are the same as in the previous period and FLAG of 1
bit indicates an equivalence to omit data transmission. Thus,
data having the same value as in the previous period is
denoted by bit number 1, so that the total data volume can be
effectively reduced.
{0091}
Data i in Fig. 7 may be changed as shown in Fig. 8. In
Fig. 8, Cmd is a command code representing a data type (e.g.,
01H indicates high pressure, and 02H indicates low pressure),
Ope is an operation code representing the operation for data
(e.g., 00H indicates display, and 01H indicates setting), and
Data is the content of data. Data may be variable. For
example, analog data may be 4 byte and digital data may be 1
byte.
{0092}
This embodiment shows a configuration in which the
control device 3 can remotely control the outdoor device 10
and the indoor device 20. Alternatively, only the outdoor
device 10 may be remotely controllable, and the indoor device
20 may be controlled by the local indoor device controlling
unit 23, for example.
{0093}
When the air conditioning system 1 consists of a
plurality of outdoor devices and a plurality of indoor
devices, the plurality of outdoor devices may be remotely
34
controlled by the control device 3 and all the indoor devices
may be controlled by the local controlling unit.
{0094}
In this embodiment, when the communication line 6 is
interrupted, the full local control mode in which the local
outdoor device controlling unit 13 and indoor device
controlling unit 23 perform control is switched on. In this
case, if another line that can communicate with the control
device 3 is present, for example, if the outdoor device 10
cannot communicate with the control device 3 but the indoor
device 20 can communicate with the control device 3, or if
another air conditioning system is present near the outdoor
device 10 and the indoor device 20 and any of the parts in the
other air conditioning system can communicate with the control
device 3, a device that can communicate with the control
device 3 may be provided as a relay to indirectly establish
intercommunication with the outdoor device 10 and the indoor
device 20. This enables remote control by the control device
3 as much as possible.
{0095}
In the air conditioning system according to this
embodiment, when the communication quality is excellent, if
the quality evaluation value is at or above a predetermined
threshold, for example, the control device 3 may send the
latest control program to the outdoor device 10 and the indoor
35
device 20. Thus, when the communication quality is excellent,
the latest control program is sent to the outdoor device 10
and the indoor device 20, so that the control programs in the
outdoor device controlling unit 13 and the indoor device
controlling unit 23 can be readily updated.
{0096}
The present invention is not limited to the above
embodiment and various modifications can be made without
departing from the scope of the invention.
{0097}
For example, the control ratio changing unit 33
dynamically changes the control ratio between the control
device 3 and the local controlling units: the outdoor device
controlling unit 13 and the indoor device controlling unit 23
according to the communication quality of the communication
line 6 computed by the communication quality monitoring unit
32 in the above embodiment. Alternatively, if variations in
the communication quality of the communication line 6 are
periodic, for example, a control mode switching schedule
depending on the communication quality may be prepared based
on the previous data and the like, and the control ratio
changing unit 33 may switch the control mode according to this
schedule. In this case, the mode selector 62 holds scheduling
information associated with time and the control mode, and the
control mode may be switched according to this scheduling
36
information, for example.
{0098}
The control ratio changing unit 33 may dynamically change
the control ratio according to information other than the
communication quality. For example, the control ratio
changing unit 33 may switch the control mode according to a
command from the indoor device controlling unit 23 which is a
local controlling unit. This enables an operation in a
control mode suitable for the operation state and the like of
the local controlling unit.
{Reference Signs List}
{0099}
1 air conditioning system
3 control device
6 communication line
10 outdoor device
13, 35 outdoor device controlling unit
20 indoor device
23, 36 indoor device controlling unit
31 communication unit
32 communication quality monitoring unit
33 control ratio changing unit
61 storage
62 mode selector
63 mode notifying unit

{CLAIMS}
{Claim 1}
A control device that is connected to an apparatus
including a local controlling unit via a communication line
and that can control the apparatus via the communication line,
the control device comprising:
a control ratio changing means that changes a control
ratio with respect to the local controlling unit, the control
ratio changing means comprising:
a storage means that contains a plurality of control
modes with different control ratios,
a mode selecting means that selects one control mode
from the plurality of control modes in accordance with
predetermined conditions, and
a mode notifying means that notifies the apparatus
of the control mode selected by the mode selecting means.
{Claim 2}
The control device according to Claim 1, further
comprising a communication quality monitoring means that
monitors a communication quality with respect to the
apparatus, wherein
the storage means contains the control modes associated
with communication quality information, and
the mode selecting means refers to information stored in
the storage means and selects a control mode corresponding to
38
the current communication quality information.
{Claim 3}
The control device according to Claim 1 or 2, wherein if
the control mode selected by the mode selecting means is
different from the previously selected control mode, the
previous control mode is continued for a predetermined period
of time and a request for a reduction in transmission data
volume is sent to the apparatus.
{Claim 4}
The control device according to Claim 2 or Claim 3
according to Claim 2, wherein if the communication quality is
at or above a predetermined threshold, the latest control
program is sent to the apparatus.
{Claim 5}
The control device according to Claim 1, wherein the mode
selecting means holds scheduling information associated with
time and a control mode and a control mode is selected
according to the scheduling information.
{Claim 6}
The control device according to Claim 1, wherein upon
reception of information on a control mode from the local
controlling unit, the mode selecting means selects the
received control mode.
{Claim 7}
The control device according to any of Claims 1 to 6,
39
wherein the control mode includes a full remote control mode
in which the control device performs control, a full local
control mode in which only the local controlling unit performs
control, and at least one of a protection control mode in
which only protection control is performed by the local
controlling unit, a target value instruction control mode in
which a control target value is given to the apparatus and
control based on the control target value is performed by the
local controlling unit, and a remote monitoring mode in which
the state value of the apparatus is monitored.
{Claim 8}
The control device according to any of Claims 1 to 7,
wherein, for current data that is contained in a packet
travelling between the apparatus and the control device and is
the same as data sent in the previous transmission period, not
the current data but information indicating that the current
data is the same as the data in the previous transmission
period is stored in the packet.
{Claim 9}
An apparatus that is connectable to the control device
according to any of Claims 1 to 8 via a communication line,
the apparatus comprising:
a storage means that contains a plurality of control
modes; and
a local controlling unit that executes, upon reception of
40
information on a control mode from the control device, control
in the received control mode.
{Claim 10}
A system comprising:
the control device according to any of Claims 1 to 8; and
the apparatus according to Claim 9.
{Claim 11}
The system according to Claim 10, further comprising the
plurality of apparatuses, wherein
when communication between any one of the apparatuses and
the control device is interrupted and communication between
any other one of the apparatuses and the control device is
established, control information for the one of the
apparatuses is sent to the one of the apparatuses via the
other one of the apparatuses.
{Claim 12}
The system according to Claim 11, wherein the plurality
of apparatuses are a plurality of indoor devices, a plurality
of outdoor devices, or an outdoor device and an indoor device.
{Claim 13}
A method of controlling a system comprising an apparatus
with a local controlling unit and a control device that can
control the apparatus via a communication line, wherein
cooperation between the local controlling unit and the
control device can execute control of the apparatus, and
a control ratio between the local controlling unit and
the control device is dynamically changed according to a
communication quality with respect to the apparatus.