Information
-
Patent Grant
-
6591620
-
Patent Number
6,591,620
-
Date Filed
Wednesday, February 6, 200222 years ago
-
Date Issued
Tuesday, July 15, 200321 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Antonelli, Terry, Stout & Kraus, LLP
-
CPC
-
US Classifications
Field of Search
US
- 062 126
- 062 132
- 236 51
- 236 47
- 705 8
- 700 276
-
International Classifications
- F25B4900
- G05D2300
- G05D1300
- G01M138
-
Abstract
A control server includes a device information database storing device characteristic data constituting the air conditioning equipment, a fuel/power rate database storing price and rate data regarding gas, oil, power and the like, a device characteristic and price database, an air conditioning equipment simulator for calculating running costs by using the data stored in the fuel/power rate database, and communication portion for performing communications through a network. The control server, and an air conditioning management controller for managing and controlling the air conditioning equipment provided with the communication portion for performing communications through the network, are connected to the network. An operation plan is made by the control server, the operation plan is transmitted to the air conditioning equipment management controller for controlling the air conditioning equipment through the network, and the air conditioning equipment is controlled and operated according to the operation plan.
Description
BACKGROUND OF THE INVENTION
The present invention relates to an air conditioning equipment operation system for operating air conditioning equipment, and a designing support system for designing and supporting the air conditioning equipment.
An example of conventional air conditioning equipment is described in JP-A-8-8-6533. The air conditioning equipment described in that document is constructed by combining absorption and compression air conditioners. During application of a low load, the absorption air conditioner is first operated. When an air conditioning load exceeds a maximum load of the absorption air conditioner, the absorption and compression air conditioners are both operated.
In addition, JP-A-7-139761 describes a system for operating a cooling tower when an outside air temperature detected by outside air temperature detecting means is lower than an indoor temperature detected by indoor temperature detecting means, in order to efficiently use energy in a clean room by using the cooling tower.
In the case of the air conditioning equipment described in JP-A-8-86533, an absorption freezer is operated with priority, and then a compression freezer is operated according to a load. However, in the air conditioning equipment described therein, the freezer to be operated is only changed to another according to cooling capability. Sufficient consideration is not always given to reductions in costs for operating each freezer by taking a characteristic thereof into consideration.
In the case of the system described in JP-A-7-139761, when the outside air temperature is low, switching is made to the operation of the cooling tower. However, since cooling capability of the cooling tower is greatly dependent on a humidity condition of an outside air, the capability of the cooling tower may not always be used satisfactorily, or cooling by the cooling tower may be impossible.
SUMMARY OF THE INVENTION
The present invention was made to remove the foregoing inconveniences of the conventional art, and it is an object of the invention is to operate air conditioning equipment by reducing running costs.
Another object of the invention is to reduce costs for air conditioning equipment including initial costs. Yet another object of the invention is to provide cold water at low costs. A further object of the invention is to achieve at least one of those objects.
In order to achieve the foregoing object, a feature of the invention is that in an air conditioning equipment operation system where a service provider company operates air conditioning equipment installed in a contract site, the service provider company sets full load or partial load running for a turbo freezer and/or an absorption freezer based on annual air conditioning load fluctuation data and/or weather data, in such a way as to minimize the total running costs of the turbo freezer and/or absorption freezer provided in the air conditioning equipment.
In this case, the total running costs may include costs of a cooling tower for radiating heat generated in a clean room accommodating a production unit of the air conditioning equipment, and heat generated by the production unit. The service provider company may control the air conditioning equipment of the contract site through a public line or Internet, and obtain the weather data from a weather forecast company through the public line or the Internet.
In order to achieve the foregoing object, another feature of the invention is that in an air conditioning equipment operation system where air conditioning equipment provided in a contract site is operated by a service provider company, the service provider company has a control server, which includes a device information database storing a device characteristic data of an air conditioner constituting the air conditioning equipment, a fuel or electricity rate database storing rate data of at least one of gas, oil and electric power, and an air conditioning equipment simulator for obtaining a partial load factor, and at least one selected from consumption of power and consumption of fuel during partial load running by using the device characteristic data and a cycle simulator, and calculating running costs from the obtained consumption of power and/or the obtained consumption of fuel by using the rate data. The contract site includes an air conditioning equipment management controller provided to manage and control the air conditioning equipment. The control server and the air conditioning equipment management controller are connected to each other through a network. The control server predicts a cooling load from predictable time series data on a temperature and humidity of outside air by referring to the device information database, and then makes an operation plan of the air conditioner. The air conditioning equipment management controller operates the air conditioner according to the operation plan.
In this case, the air conditioning equipment simulator calculates running costs for each operation of the air conditioner, and makes operation plan data by an operation method having lowest running costs among the calculated running costs; the air conditioning equipment includes absorption and turbo freezers, and the air conditioning equipment simulator selects full or partial loads of the freezers according to a set amount of cooled heat of the absorption and turbo freezers, and calculates running costs in this case; the air conditioning equipment includes a cooling tower, and the air conditioning equipment simulator calculates running costs according to the operation/stop of the cooling tower; an object to be cooled provided in the air conditioning equipment is cooled by cold water generated by a cold water generator of the service provider company, a temperature sensor for detecting a cooled heat amount of this cold water is provided in the vicinity of the object to be cooled, and the air conditioning equipment simulator obtains an amount of heat for colling from a temperature detected by the temperature sensor, and calculates a use rate of the contract site; the control server predicts a cooling load from prediction data on a temperature and humidity of an outside air purchased from a weather forecast company, and the air conditioning equipment simulator sets an operation method of the air conditioning equipment in the air conditioning equipment management controller through a web based on the predicted cooling load; means may be provided for detecting the temperature and humidity of the outside air, means may be provided for detecting a cooling load of the air conditioning equipment, an equation of relation between the cooling load and the temperature and humidity of the outside air may be obtained from the temperature and humidity of the outside air, and the cooling load detected by the detecting means, and a cooling load may be predicted by using this equation of relation.
In order to achieve the foregoing object, yet another feature of the invention is that an air conditioning equipment designing support system for supporting designing of a number of air conditioners provided in air conditioning equipment comprises: a step (A) of generating an annular cooling load fluctuation pattern of the air conditioning equipment; a step (B) of calculating initial costs by referring to He a device information database storing device characteristics and prices of the number of air conditioners; a step (C) of calculating annual running costs from the annual cooling load fluctuation pattern by referring to the database storing the device characteristics and the prices, and a database storing fuel and electricity rates; a step (D) of calculating costs including device taxes and interest rates; and a step (E) of calculating total costs including the initial costs, and running costs of a set number of years. By changing the configuration of the air conditioners of the air conditioning equipment, and repeating the steps (B) to (E), each air conditioner of the air conditioning equipment is set in such a way as to minimize the total costs.
In this case, preferably, an annual cooling load pattern is produced by using a weather information database storing weather data on a past temperature and humidity of an outside air.
In order to achieve the foregoing object, a further feature of the invention is that in an air conditioning equipment operation system where air conditioning equipment provided in a contract site is operated by a service provider company, an object to be cooled in the air conditioning equipment is cooled by cold water generated by a cold water generator of the service provider company, a cooled heat amount of this cold water is obtained from outputs of a temperature sensor and a flow meter installed in the vicinity of the object to be cooled, and a use rate is obtained by calculating this obtained cooled heat amount with a predetermined rate.
Other objects, features and advantages of the invention will become apparent from the following description of the embodiments of the invention taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a block diagram showing an air conditioning equipment operation system according to an embodiment of the present invention.
FIG. 2
is a block diagram showing an air conditioning equipment management controller used in the air conditioning equipment operation system of FIG.
FIG. 3
is a system flowchart of air conditioning equipment used the air conditioning equipment operation system of FIG.
1
.
FIG. 4
is a view illustrating running costs of a freezer.
FIG. 5
is a view illustrating an operation pattern of the freezer.
FIG. 6
is a view illustrating running costs of the freezer.
FIG. 7
is a view illustrating a cooling load of a clean room.
FIG. 8
is a view illustrating a cooling load of the air conditioning equipment.
FIG. 9
is a flowchart for operating the air conditioning equipment.
FIG. 10
is a view illustrating a change in the cooling load.
FIG. 11
is a view illustrating another change in the cooling load.
FIG. 12
is a flowchart for optimizing air conditioner designing.
FIG. 13
is a view showing an example of a device configuration data set.
FIG. 14
is a view illustrating consumption of power in the air conditioning equipment.
FIG. 15
is a view illustrating load fluctuation.
FIG. 16
is a view illustrating privity of contract between companies.
FIG. 17
is a view illustrating privity of contract between companies.
FIG. 18
is a system flowchart of air conditioning equipment according to another embodiment.
FIG. 19
is a view illustrating an operation of a cooling tower.
FIG. 20
is a view illustrating running costs of the air conditioning equipment.
FIG. 21
is a view illustrating an operation of a cooling tower.
FIG. 22
is a view illustrating cooling costs.
DESCRIPTION OF THE EMBODIMENTS
Next, description will be made of the embodiments of the present invention with reference to the accompanying drawings.
FIG. 1
shows an entire configuration of an air conditioning equipment operation system according to an embodiment of the invention. In the air conditioning equipment operation system, a service provider company
2
is connected to contract sites
1
,
1
a
and
1
b
through a network
10
. The service provider company
2
has a control server
20
. Various bits of information stored in the control server
20
are transmitted to/received by an air conditioning equipment management controller
30
of the contract site
1
through the network
10
. In the contract site
1
, an air conditioning equipment communication line
38
is connected to enable data to be transmitted from the air conditioning equipment management controller
30
to each device constituting air conditioning equipment
39
or received from each device.
The service provider company
2
has a weather forecast information provision contract with a weather forecast company
8
. Weather forecast data is provided from the weather forecast company
8
to the service provider company
2
through the network
10
. The weather forecast data is prediction data containing a temperature and humidity of an outside air. The service provider company
2
makes an operation plan for the air conditioning equipment
39
of the contact site
1
by using the weather forecast data of the weather forecast company
8
. Based on this operation plan, the air conditioning equipment controller
30
manages and controls the air conditioning equipment
39
. Cold water is supplied from the air conditioning equipment
39
to a contract company
11
, and each room of the contract company
11
is air-conditioned, or a device is cooled. A relation between the contract site
1
and the contract company
11
is set, for example in a manner that the contract company owns a plant or a building, and takes air conditioning equipment including running control on lease or the like from the contract site
1
. Accordingly, the contract site
1
is responsible for entire management of an air conditioner of the contract company
11
.
The control server
20
of the service provider company
2
has hardware including communication means
52
for controlling communications through the network
10
, input/output means
51
including a display, a keyboard, a mouse and the like, storage means
54
such as a hard disk, and calculation means
53
such as a microcomputer. The control server
20
also includes a fuel/power rate database
21
, a device information database
24
, a system configuration database
22
, a running record database
25
, a weather information database
23
, operation control means
41
, an air conditioning equipment simulator
42
, device characteristic correction means
43
, operation method optimizing means
44
, and equipment designing support means
45
.
The device information database
24
stores characteristic and price data on devices constituting the air conditioning equipment
39
connected to the air conditioning equipment management controller
30
. These data include device characteristic and price data provided from a manufacturing company of each device, and device characteristic data corrected by the device characteristic correction means
43
based on running record data of such a device. The fuel/power rate database
21
stores a gas rate of a gas supply company
4
, a power rate of a power supply company
5
, and an oil sales price of an oil selling company
6
from the past to the present.
The weather information database
23
stores weather data including a temperature, humidity and the like. The weather data includes data such as AMEDAS (Automated Meteorological Data Acquisition System) provided by Meterological Agency, and weather forecast data forecast by the weather forecast company
8
. Each weather forecast data is transmitted from the weather forecast company
8
to the contract sites
1
,
1
a
and
1
b
through the network
10
, and stored in the weather information database
23
.
The running record database
25
stores running record data of the air conditioning equipment
39
installed in the contract site
1
. The running record data is obtained by recording data measured by a measuring device attached to each part of the air conditioning equipment, and a running start/stop signal of each device in time series. This running record data is transmitted from the air conditioning equipment management controller
30
periodically or according to a request of the control server
20
.
The system configuration database
22
stores system configuration data of the air conditioning equipment of each of the contract sites
1
,
1
a
and
1
b
. As the system configuration data of the air conditioning equipment, there are configuration information and connection information of each device of the air conditioning equipment.
The running control means
41
controls transmission of operation plan data of the air conditioning equipment to the air conditioning equipment management controller
30
through the network
10
, stores and manages the running record data of the air conditioning equipment
39
received from the air conditioning equipment management controller
30
through the network
10
in the running record database
25
, calculates a rate to be charged to the contract company
11
from the running record data, calculates rates to be m paid to the weather forecast company
8
, the power supply company and the gas supply company, and manages a state of money input/output. The running plan data of the air conditioning equipment contains a running start/stop command, and a target control value of each device provided in the air conditioning equipment.
The air conditioning equipment simulator
42
simulates an air conditioner installed in the contract site
1
. Software loaded in the air conditioning equipment simulator
42
includes a program for calculating a load rate of a pump or a freezer to be used from the information of the device connected to the air conditioning equipment
39
, a program for calculating an exchanged heat amount of a cooling coil or a dry coil provided in the air conditioning equipment
39
, and a temperature of water or air in an outlet of the cooling coil or the dry coil, a program for calculating an amount of exchanged heat, and a temperature in an outlet of the heat exchanger, a program for simulating a freezing cycle of the freezer, and a program for calculating a cooled heat amount of the cooling tower, and a temperature of cold water in an outlet of the cooling tower.
The air conditioning equipment simulator
42
calculates a partial load rate, consumption of power and consumption of fuel of each device from data on, for example a temperature and humidity of an outside air, a cooling load and a control target value of each device, by referring to the device characteristic data stored in the device information database
24
, and the air conditioning equipment system configuration data of the contract site
1
stored in the device configuration database
22
. In addition, the air conditioning equipment simulator
42
calculates running costs following the consumption of power and the consumption of fuel by referring to the power rate data, the gas rate data and the oil price data stored in the fuel/power rate database.
When fuel consumption of the absorption freezer
32
and power consumption of the turbo freezer
33
are calculated from the cooling load, if a parameter value necessary for calculating a freezing cycle such as heat transfer performance of an evaporator or a condenser provided in each freezer is known, the consumption of power is calculated by using a cycle simulator. If such a parameter value necessary for freezing cycle calculation is not known, the consumption of power is calculated by using a relation between the cooling load and the power consumption of the turbo freezer
33
, described leter with reference to FIG.
15
.
The device characteristic correction means
43
corrects device characteristic data of the air conditioning equipment by referring to the running record data of the air conditioning equipment stored in the running record database
25
, and then stores the corrected data in the device information database
24
. A change made in the device characteristic because of deterioration of the device is recorded. The operation method optimizing means
44
searches a method for operating the air conditioning equipment installed in the contract site
1
so as to minimize running costs, and makes running plan data. The equipment designing support means
45
searches an air conditioning equipment configuration, which reduces total costs including initial costs, running costs, maintenance costs, and disposal costs, when designing or replacing the air conditioning equipment.
A planning engineer of the service provider company
2
makes an operation plan, a maintenance plan, or a replacement plan for the air conditioning equipment
39
provided in the contract sites
1
,
1
a
and
1
b
by using the control server
20
, and designs air conditioning equipment for a new contract site. The control server
20
of the service provider company
2
stores the fuel/power rate database
21
, the device information database
24
, the system configuration database
22
, the running record database
25
, and the weather information database
23
. When the air conditioning equipment of the new contact site is designed, if there is a contract site currently using a similar device or having used the similar device in the past, and data accumulated in this contract site can be used, the air conditioning equipment can be designed in detail by using the accumulated data.
Since the device characteristic including the running record data of the other contract site using the similar device can be examined, a more accurate operation plan can be made. In addition, when maintenance is necessary, if the similar device is used, a similar running history tendency is exhibited. Thus, when similar devices are used by a plurality of contract sites, a maintenance plan can be made by using the stored past running history tendency needing maintenance. As contract conditions of fuel power rates are stored en block in the fuel/power rate database
21
, by selecting a period of small fuel or power consumption so as to consume more fuel or power, fuel or power can be bought at low costs.
FIG. 2
shows in detail the air conditioning equipment management controller
30
of FIG.
1
. The air conditioning equipment management controller
30
has hardware including communication means
61
for controlling communications through the network
10
, input/output means
65
, e.g., a display, a keyboard and a mouse, storage means
62
such as a hard disk, calculation means
63
including a microcomputer, and air conditioning equipment communication means
64
for controlling communications with the air conditioning equipment
39
. Air conditioning equipment management control means
66
for operating the air conditioning equipment is software.
The storage means
62
stores running record data
69
, and weather forecast data
68
and running plan data
67
transmitted from the control server
20
of the service provider company
2
. The air conditioning equipment communication means
64
of the air conditioning equipment management controller
30
transmits/receives data of each device provided in the air conditioning equipment
39
through the air conditioning equipment communication line
38
.
The air conditioning equipment management controller
66
manages and controls the air conditioning equipment
39
. The air conditioning equipment
39
is controlled by referring to the running plan data
67
transmitted from the control server
20
of the service provider company
2
and stored in the storage means
62
. Also, a measurement value measured by a measuring device and a running value of each device are stored as the running record data
68
in the storage means
62
. The air conditioning equipment management control means
66
receives the running plan data and the weather forecast data transmitted from the control server
20
, and transmits the running record data to the control server.
A manager of the contract site
1
operates the input/output means
65
to check a running state of the air conditioning equipment
39
or the measurement value of the measuring device, and accesses information regarding the fuel/power rate database
21
, the device information database
24
, the system configuration database
22
, and the running record database
25
of the control server. In addition, the operation control means
41
, the air conditioning equipment simulator
42
, the device characteristic correction means
43
, the operation method optimizing means
44
, and the equipment designing support means
45
of the control server are used.
FIG. 3
shows an example of the air conditioning equipment
39
of the contract site
1
. The air conditioning equipment
39
includes the absorption and turbo freezers
32
and
33
. These freezers
32
and
33
cool cold water, and the cooling load is cooled by the cooled cold water. The cold water is stored in a cold water tank
460
.
Now, a device for producing this cold water is described by referring to FIG.
3
. Cooling water of the absorption freezer
32
is guided to a cooling tower
310
by a cooling water pump
340
, and cooled. Similarly, cooling water of the turbo freezer
33
is guided to a cooling tower
311
by a cooling water pump
341
, and cooled. A cold water primary pump
342
driven by an inverter
400
guides the cold water from the cold water tank
460
to the absorption freezer
32
. Similarly, a cold water primary pump
343
driven by an inverter
431
guides the cold water from the cold water tank
460
to the turbo freezer
33
. Instead of changing a load rate by using the inverters
400
and
431
, three-way valves
860
and
861
may be respectively provided in the absorption and turbo freezers
32
and
33
and, by controlling these three-way valves
860
and
861
, load rates of the respective freezers may be changed. A detail will be described leter.
In the absorption freezer
32
, its not-shown controller controls the absorption freezer
32
such that a value detected by a cold water outlet temperature sensor
806
can be equal to a preset target temperature. Similarly, in the turbo freezer
33
, its not-shown controller controls the turbo freezer
33
such that a value detected by a cold water outlet temperature sensor
807
can be equal to a target temperature. In the air conditioning equipment of the embodiment, a target temperature is set to 7° C. The target temperature can be changed by a command from the air conditioning equipment management controller
30
.
The following elements are attached to the absorption freezer
32
: a temperature sensor
808
for detecting a cold water inlet temperature; the temperature sensor
806
for detecting a cold water outlet temperature; a flow meter
830
for detecting a cold water flow rate; a temperature sensor
804
for detecting a cooling water inlet temperature; a temperature sensor
802
for detecting a cooling water outlet temperature; and a flow meter
834
for detecting a cooling water flow rate. The following elements are attached to the turbo freezer: a temperature sensor
809
for detecting a cold water inlet temperature; the temperature sensor
807
for detecting a cold water outlet temperature; a flow meter
831
for detecting a cold water flow rate; a temperature sensor
805
for detecting a cooling water inlet temperature; a temperature sensor
803
for detecting a cooling water outlet temperature; and a flow meter
835
for detecting a cooling water flow rate. Outputs of the temperature sensors
802
to
809
and the flow meters
830
and
831
are used for calculating an amount of cooled heat of the absorption and turbo freezers
32
and
33
.
An amount of heat Q
32
(kW) for cooling of the absorption freezer
32
is calculated by the following equation (1):
Q
32
=
cp×ρ×W
830
/60×(
T
808
−
T
806
) (1)
In the equation (1), Q
32
denotes a cooled heat amount (kW) of the absorption freezer
32
; cp specified heat at constant pressure for water (kl/kg° C.); ρ a water density (kg/m3); W
830
a measurement value (m3)/mon.) of the flow meter
830
; T
806
a measurement value (° C.) of a thermometer
806
; and T
808
a measurement value (° C.) of a thermometer T
808
.
In the pumps
340
to
343
for circulating cold water and cooling water, since there is a fixed relation between a flow rate and a current, a flow rate may be calculated by connecting am ammeter to the cold water primary pump
342
, and using a value measured by this ammeter, a current of the pump and device characteristic data of the pump. If a flow rate is obtained by using the current of the pump and the device characteristic data of the pump, costs can be reduced because the ammeter is more inexpensive than the flow meter. However, accuracy is lower compared with the flow meter. A cooled heat amount of the turbo freezer
33
can be calculated by a similar method.
Amounts of heat cooled by the respective cooling towers
310
and
311
are calculated from temperatures and flow rates detected by the temperature sensors
802
to
805
, and the flow meters
834
and
835
. Data on measurements by these sensors are also used for analyzing device characteristics, and by the device characteristic correction means
43
.
Next, description is made of an example of a configuration of a cooling load side as a cold water secondary side. The cold water produced by the absorption and turbo freezers
32
and
33
and stored in the cold water tank
460
is sent to a cold water header
450
by a cold water secondary pump
344
. Then, a part thereof is supplied to a cold water coil
424
provided in an outside air conditioner
430
. A pressure sensor
840
is attached to the cold water header
450
. A pipe for returning cold water to the cold water tank is connected to the cold water header
450
, and an automatic valve
862
is attached to this pipe. The automatic valve
862
is controlled such that a pressure detected by the pressure sensor
840
can be equal to a preset pressure.
The outside air conditioner
430
is an air passage formed in a rectangular duct shape and, from a left end part of
FIG. 3
, outside air is captured in this duct by a blower
350
. Dust of the outside air captured by the blower
350
is removed by filters
420
and
422
. A preheating coil
421
is disposed between the filters
420
and
422
; and in the downstream side of the filter
422
, a humidifier
423
, the blower
350
, a cooling coil
424
, and a reheating coil
425
in this order. A temperature sensor
813
is disposed in the vicinity of the cooling coil
424
. The outside air captured in the outside air conditioner
430
is adjusted for its temperature and humidity to a target temperature and target humidity by the preheating coil
421
, the humidifier
423
, the cooling coil
424
and the reheating coil
425
. The outer air adjusted for its temperature and humidity is guided to a clean room
360
.
The cold water guided to the cooling coil
424
of the outside air conditioner
430
is returned through the automatic valve
865
to the cold water tank
460
. The automatic valve
865
is controlled such that a temperature detected by the temperature sensor
813
can be equal to a set temperature. To detect a temperature and a flow rate of the cold water supplied to the cooling coil
424
, a temperature sensor
811
and a flow meter
813
are provided in a cold water supply pipe
458
and, to detect a return temperature, a temperature sensor
812
is provided in a return pipe
459
.
To heat the outside air captured into the outside air conditioner
430
, steam is supplied from a not-shown boiler through a pipe
451
to the preheating coil
421
, the humidifier
423
and the reheating coil
425
. To control the amount of steam supplied to such a device based on the temperature and humidity of the outside air captured into the outside air conditioner
430
, detected by a not-shown sensor, an automatic valve
870
is attached to a downstream side of the preheating coil
421
; an automatic valve
871
to an upstream side of the humidifier
423
; and an automatic valve
872
to a downstream side of the reheating coil
425
.
Water having its temperature lowered by heat exchanging of each device, and steam condensed, is returned through a pipe
452
to the boiler. A flow meter
835
and a temperature sensor
822
are attached to the steam supply pipe
451
; and a flow meter
836
and a temperature sensor
823
to the condensed water return pipe
452
.
A part of the cold water supplied to the cold water header
450
is used for cooling air in the clean room
360
. A heat exchanger
455
for dry coil cooling water is attached to a cold water pipe
471
branched from the cold water pipe
458
. The outside air distributed in the clean room
360
is heat-exchanged with cooling water circulated in a cooling water pipe
472
by a dry coil
427
. This cooling water is heat-exchanged with cold water distributed in the cold water pipe
471
by the heat exchanger
455
for the dry coil cooling water.
The amount of cooling water distributed in the dry coil
427
by a dry coil cooling water pump
345
is adjusted by an automatic flow rate adjusting valve
866
such that values detected by a temperature sensor
814
in a dry coil inlet side, a flow meter of the dry coil
427
, and a temperature sensor
816
in a dry coil outlet side can be equal to preset values. The cold water increased in temperature by the heat exchanger
455
for dry coil cooling water is returned from a cold water pipe
459
to the cold water tank
460
. An automatic flow rate adjusting valve
964
provided between the heat exchanger
455
for dry coil cooling water and the cold water pipe
459
is controlled such that a temperature detected by the temperature sensor
814
can be set equal to a preset temperature.
Another part of the cold water supplied to the cold water head
450
is passed through the pipe
472
branched from the pipe
458
, and used for cooling a production device
411
installed in the clean room
360
. The cold water distributed through the pipe
472
is heat-exchanged with cooling water for cooling the production device
411
by a heat exchanger
456
for production device cooling water. The cold water increased in temperature by the heat-exchanging with the cooling water is returned from the cold water pipe
459
to the cold water tank
460
. An automatic flow rate adjusting valve
863
is provided between the heat exchanger
456
for production device cooling water and the cold water pipe
459
, and adapted to adjust the amount of cold water distributed in the pipe
459
.
The cooling water for cooling the production device
411
is supplied from a production device cooling water tank
461
to the heat exchanger for device cooling water by a device cooling water pump
347
, heat-exchanged with the cold water, and then supplied through a cooling water pipe
473
to the production device
411
. The cooling water having cooled the production device
411
is returned through a cooling water pipe
474
to the production device cooling water tank
461
. The following elements are attached to the cooling water pipe
473
: a temperature sensor
820
for detecting a cooling water inlet temperature; a pressure sensor
841
for detecting an inlet pressure; and a flow meter
834
for detecting the amount of cooling water. A temperature sensor
821
for detecting a cooling water outlet temperature is attached to the cooling water pipe
474
. A pipe is provided, which is branched from the cooling water pipe
473
to return the cooling water to the production device cooling water tank
411
, and an automatic valve
869
is attached to this pipe. This automatic valve
869
is controlled such that a pressure detected by the pressure sensor
841
can be equal to a preset pressure.
The outside air captured into the clean room
360
is guided to a filter
426
by fan units
355
,
355
, . . . , supplied to a partition room
361
disposed in the production device
411
after its dust is removed, forming a down-flow in the partition room
361
. Subsequently, the outside air is passed from a floor surface having a grating to the outside of the partition room
361
, and heat-exchanged with the cooling water by the dry coil
427
to be cooled. A temperature sensor
801
for measuring a temperature in the partition room
361
, and a hygrometer
851
for measuring humidity are respectively provided in proper positions in the partition room
361
.
An exchanged heat amount of the cooling coil
424
provided in the outside air conditioner
430
is calculated from detected values of two temperature sensors
811
and
812
and a flow meter
832
provided in the cold water pipe
458
. An exchanged heat amount of the dry coil
427
is calculated from detected values of temperature sensors
814
and
816
and a flow meter
833
provided in the cooling water pipe of the dry coil
427
. A heat amount for cooling of the production device
411
is calculated from detected values of temperature sensors
820
and
821
and a flow meter
834
provided in the cooling water pipes
473
and
474
of the production device
411
. By totaling the above amounts of heat, a cooling load of the entire clean room
360
is obtained.
A mass flow rate of steam distributed in the pipe
451
of the outside air conditioner
430
is calculated from detected values of the temperature sensor
822
and the flow meter
835
. Then, a mass flow rate of water distributed in the pipe
452
of the outside air conditioner
430
is calculated from detected values of the temperature sensor
823
and the flow meter
836
. By subtracting the mass flow rate of water distributed in the pipe
452
from the mass flow rate of steam distributed in the pipe
451
, an amount of steam to be used by the hygrometer
423
provided in the outside air conditioner
430
is obtained.
From detected values of the temperature sensors
822
and
823
and the flow meter
836
attached to the pipes
451
and
452
of the outside air conditioner
430
, a specific enthalpy of the steam distributed in the pipe
451
, a specific enthalpy of the water distributed in the pipe
452
, and a mass flow rate are calculated. By using these values, a total amount of heat exchanged between the preheating coil
421
and the reheating coil
425
of the outside air conditioner
430
is represented by the following equation (2):
(
Q
421
+
Q
425
)=
G
452
×(
h
451
−
h
452
) (2)
In the equation (2), Q
421
denotes an amount of exchanged heat (kW) of the preheating coil
421
; Q
425
an god amount of exchanged heat (kW) of the reheating coil
425
; G
452
a mass flow rate (kg/s) of the water in the pipe
452
;
451
a specific entropy (kj/kg) of the steam in the pipe
451
; and h
452
a specific entropy (kJ/kg) of the water in the pipe
452
.
The clean room
360
includes a power source
410
for the production device
411
, consumption of power is measured by a wattmeter
855
. Heat generated by a device such as the production device
411
becomes a cooling load of air in the clean room or device cooling water. As most of the power consumed becomes heat, the consumption of power measured by the wattmeter
855
is used for cooling load analysis. To measure a temperature and humidity of the outside air, a thermometer
800
and a hygrometer
850
are provided in an instrument screen
300
.
The absorption and turbo freezers
32
and
33
, their respective accompanying cooling towers
310
and
311
, the following elements provided in the air conditioning equipment operation system, i.e., the pumps
340
to
347
, the valves
860
to
872
, the temperature sensors
800
to
825
, the hygrometers
850
and
851
, the flow meters
830
to
836
, and the pressure sensors
840
and
841
, are connected to the air conditioning equipment management controller
30
, or connected with one another by using the air conditioning equipment communication line
38
. By using the air conditioning equipment communication line
38
, running of each device of the air conditioning equipment is started/stopped, and a control target value is changed. Moreover, a detected value of each sensor such as the temperature sensor, the pressure sensor or the flow meter, and a running signal or a stop signal of each device are transmitted.
Next, description is made of a method of operating the absorption and turbo freezers
32
and
33
in combination.
FIG. 4
shows a calculation example of a running cost index per a unit amount of cooled heat for a cooling load in each of the absorption and turbo freezers
32
and
33
. A value shown can be calculated by referring to the partial load characteristic data of each of the absorption and turbo freezes
32
and
33
stored in the device information database
24
, and the gas rate and power rate data stored in the fuel/power rate database
21
.
A value at 100% of a cooling load is when each of the absorption and turbo freezers
32
and
33
is run by maximum cooling capability. Hereinafter, % indication represents a ratio of the freezer to the maximum cooling capability. In the case of the turbo freezer
33
, efficiency is high if it is operated at a maximum cooling capability point, and the efficiency is lowered as the amount of cooled heat is reduced. On the other hand, in the case of the absorption freezer
32
, a change in efficiency is only slightly increased even when the amount of heat is reduced. In
FIG. 4
, a ratio of coefficients of performance (COP) between the absorption and turbo freezers
32
and
33
during cooling is set to 1:4.7, and a ratio of unit prices between gas and power is set to 1:4.2.
In
FIG. 4
, characteristics of the absorption and turbo freezers intersect each other at the amount of cooled heat X. Running costs are lower if the turbo freezer
33
is used when a cooling load is X or higher, and if the abruption freezer
32
is used when a cooling load is X or lower.
FIG. 5
shows an example of operating the absorption and turbo freezers
32
and
33
in combination. Maximum cooling capabilities of the absorption and turbo freezers
32
and
33
are similarly set to 100%.
As running costs are lower if the absorption freezer
32
is used up to X% of a cooling load, the absorption freezer
32
is run. When a cooling load is X% or higher and within a range of 100% or lower, running costs are lower if the turbo freezer
33
is used. Thus, the turbo freezer
33
is run. When a cooling load exceeds 100% and reaches 120% or lower, 20% of the cooling load is cooled by the absorption freezer, and a remaining part of the cooling load is cooled by the turbo freezer. When a cooling load is 120% or higher, 100% of the cooling load is cooled by the turbo freezer, and a remaining part of the cooling load is cooled by the absorption freezer.
FIG. 6
shows an example of a change in a running cost index per a unit amount of cooled heat when there are two turbo freezers and two absorption freezers, in a case where one turbo freezer and one absorption freezer are run in combination. It is assumed that when the two turbo freezers and the two absorption freezers are used, one freezer is run if a cooling load is 100% or lower, and two freezers are run if a cooling load is larger than 100%; and maximum amounts of cooled heat for the two freezers are equal to each other.
At about 155% or higher of a cooling load, running costs are smallest if the two turbo freezers are used. In the range of a cooling load other than this, running costs become smallest by using one each of the absorption and turbo freezers, and running the freezers according to the operation method of FIG.
5
.
The maximum cooling capability of the freezer is set somewhat enough to spare even in summer when a cooling load is large. A ratio of time for running the freezer in a load zone of summer season when a cooling load is largest is small in running time throughout four seasons. In other words, running time is short at near 200% of a cooling load.
FIG. 7
shows a change in a cooling load with respect to a specific enthalpy of an outside air in the clean room. A line
970
indicates a total amount of heat generated from the production device
411
, the fan unit
355
, illumination, a worker and the like in the clean room
360
. The heat generated in the clean room
360
is carried away by cooling water distributed through the dry coil
427
and cooling water for cooling the production device. The amount of this heat is represented as a load
974
of the dry coil
427
and a cooling load
973
of the production device. A line
971
indicates a total amount of the heat generated in the clean room and a cooling load of the outside air. Inclination of the line
971
is equivalent to a mass flow rate (kg/s) of introduced outside air. At a point
972
, a cooling load of outside air absorbed from the outside air conditioner
430
is eliminated.
FIG. 8
shows an example of a distribution of a cooling load. Use of air conditioning equipment having the cooling load characteristic shown in
FIG. 7
is assumed. Regarding a outside air condition, a condition of one region in Japan is assumed. For each ratio of a cooling load to the maximum cooling capability of the freezer, an accumulated time of an operation by the load, and an accumulated amount of heat are shown.
Now, description is made of a method for reducing costs of the air conditioning equipment operation system under the foregoing condition and characteristic.
FIG. 9
shows a method for reducing gas and power rates by using the operation method optimizing means
44
. Gas and power rates fluctuate due to seasonal or external factors. When a temperature or humidity of an outside air is changed even if a cooling load is maintained constant, changes occur in the amounts of cooled heat of the cooling towers
310
and
311
of the freezers. Consequently, a cooling water temperature is changed to cause changes in running costs of the absorption and turbo freezers
32
and
33
.
Now, the air conditioning equipment
39
shown in
FIG. 3
is taken as an example. The operation method optimizing means
44
sets time to zero hour as a plan start time (step
800
S). Then, predicted values of a temperature and humidity of outside air are read (step
801
S). For the predicted values of the temperature and humidity of the outside air, forecast values of the weather forecast company
8
are used. If operation time is different from the predicted time of the weather forecast company
8
, a predicted value of operation time is obtained by interpolating data sent from the weather forecast company.
A predicted value of a cooling load is calculated (step
802
S). A predicted value of a specific enthalpy of the outside air is calculated based on the predicted values of the temperature and humidity thereof. After the specific enthalpy is obtained, a cooling load is calculated based on the relation between the specific enthalpy and the cooling load of the outside air shown in FIG.
7
. The relation between the specific enthalpy and the cooling load of the outside air shown in
FIG. 7
is prepared beforehand by a leter-described method based on the running record data stored in the running record database
25
.
Then, an operation method is set (step
803
S). It is assumed that air conditioning equipment has a characteristic similar to that shown in
FIG. 5
, and a predicted value X of a cooling load is 150%. In this case, since a shortage of cooling capability occurs if only one freezer is used, two freezers are necessary.
If X
1
denotes a target amount of cooled heat of the absorption freezer
32
, and X
2
a target amount of cooled heat of the turbo freezer
33
, there are following three possible combinations. Such combinations are stored beforehand in the database.
X
2
=100
, X
1
=
X
−X
2
(1)
X
1
=100
, X
2
=
X
−X
2
(2)
X
1
=
X
/2
, X
2
=
X
/2 (3)
Running costs when the operation method (1) is used are calculated by using the air conditioning operation simulator (step
804
S). As the calculated running cots are used again in step
810
S, the running costs are stored in the storage means. This process is executed for all the three operation methods. After all the operation methods (1) to (3) are calculated, the calculation is stopped, and the process proceeds to step
807
S (step
805
S). If there are any cases remaining to be calculated, the process proceeds to step
806
S, where other operation methods are calculated. Results of the calculated three running costs are compared with one another, a most inexpensive operation method is selected, and this operation method is outputted (step
807
S).
A candidate operation method of the freezer obtained for each cooling load is as follows:
In the case of X≦100,
X
1
=
X, X
2
=0 (A)
X
1
=0
, X
2
=
X
(B)
In the case of 100<X≦120,
X
1
=20
, X
2
=
X−X
1
(C)
X
2
=20
, X
1
=
X−X
2
(D)
X
1
=
X
/2
, X
2
=
X
/2 (E)
In the case of 120<X≦200,
X
2
=100
, X
1
=
X−X
2
(F)
X
1
=100
, X
2
=
X−X
1
(G)
X
1
=
X
/2
, X
2
=
X
/2 (H)
Then, determination is made as to whether time is an operation end time or not (step
808
S). If the time is not the operation end time, the time is advanced by predetermined time (step
809
S). By setting a time interval to be 10 min., the time is advanced by 10 min. This operation is repeated, and an operation plan of one day described for each 10 min., is made. After the operation plan of one day is made, consideration is given to running cots at the time of starting/stopping the device operation (step
810
S).
After the operation of the freezer is started by setting an operation method, if an operation method is changed during the same day, running costs occur following the start/stop of the device running. Thus, comparison is made in running costs between the case of changing an operation method and the case of not changing an operation method in a day, and an operation method of lowest running costs is selected. For example, a plan is made in a manner that the turbo freezer is run until 24:00 of a day before a planning day, the turbo freezer is run from 0:00 to 12:00 of the planning day, the absorption freezer is run from 12:00 to 15:00, and the turbo freezer is run from 15:00 to 24:00. In this case, operation methods (4) to (6) described below are compared with one another, and one having lowest running costs is selected.
(4) The turbo freezer is run from 0:00 to 12:00; the absorption freezer from 12:00 to 15:00; and the turbo freezer from 15:00 to 24:00.
(5) Only the turbo freezer is run continuously from 0:00 to 24:00.
(6) Only the absorption freezer is run continuously from 0:00 to 24:00.
Since the calculation result of the running costs was stored in step
804
S of
FIG. 9
, it is not necessary to calculate running costs. Since the turbo freezer is run on a previous day, in the operation method (6) switching to the absorption freezer, or the operation method (4) switching the operated freezer to another in the midway, running costs occur following the operation start/stop of the device. These costs are added. By the operation in step
810
S, the inconvenience of operation switching in a short time can be removed.
The operation plan made by the operation method optimizing means
44
is sent as operation plan data through the network
10
to the air conditioning equipment management controller
30
. The operation plan data is composed of“condition” and“operation”, e.g., in a form of “if . . . , then . . .”. The air conditioning equipment management controller
30
operates the air conditioning equipment based on this operation plan data. At the time of starting the operation, it takes time for the device to be set in a stationary state. The operation plan data is prepared by considering the time of this transient state. In the case of the absorption freezer, 30 min., or less is necessary to reach a stationary state. Thus, to set the absorption freezer in a stationary state at 12:00, operation plan data for starting operation of the absorption freezer by 11:30 is made.
The “condition” may be time, a physical quantity obtained from a measurement value of a temperature or the like of the outside air, or a detected value of a cooling load or the like, or a combination thereof. If the “condition” is a combination of the physical quantity calculated from the measurement value of the temperature of the outside air of the time for changing the operation or the detected value of the cooling load, with a time range, an advantage is provided because it is not necessary to change the operation plan data even if an actual temperature and humidity are slightly different timewise from predicted values of a temperature and humidity obtained from weather forecast. For example, if it is planned that “operation of the absorption freezer
32
is started at 10:00, and a cooling load is 95% at this time”, operation plan data, i.e., “when a cooling load is 95% or higher from 9:00 to 11:00, operation of the absorption freezer is started”, is made. Thus, it is possible to deal with a situation where an increase in the temperature of the outside air is somewhat quickened, and a cooling load reaches 95% at 9:30.
If the actual temperature and humidity exceed a permissible range obtained from the weather data predicted by the weather forecast company
8
, or if the weather forecast company
9
changes a weather forecast, the operation plan is reviewed. If the actual temperature and humidity are not as predicted, causing a shortage of cooling capability of the freezer, the freezer that has not been operated is run. This setting is prestored in the air conditioning equipment management control means
66
of the air conditioning equipment management controller
30
. When this setting is executed, the operation plan is reviewed.
Each of
FIGS. 10 and 11
shows an example of an operation plan displayed on a control monitor of an air control monitor of the air conditioning equipment management controller
30
. The planning engineer of the service provider company
2
verifies the operation plan and predicted and measurement values of a cooling load by using the input/output means of the control server
20
; the manager of the contract site
1
by using input/output means
65
of the air conditioning equipment management controller
30
. The predicted and measurement values of the cooling load, a current time and a predicted value of running costs are displayed. In
FIG. 10
, predicted values of cooled heat amounts of the absorption and turbo freezers
32
and
33
are also displayed. In
FIG. 11
, maximum values of cooling capabilities of the absorption and turbo freezers
32
and
33
are also displayed.
A current time in the drawing is 22:30 of Jul. 1, 2001 and, from a screen of
FIG. 11
, it can be seen that a predicted value of a cooling load becomes 100% around 9:10 of July 2, causing a shortage of cooling capability in the case of using only the turbo freezer. As it takes 30 min., or less to reach a stationary state from the operation state of the absorption freezer
32
, the absorption freezer
32
may be actuated to compensate for cooling capability at 8:40. Since a cooling load becomes 94% at 8:40, it is planned that the operation of the absorption freezer
32
is started when the cooling load becomes 94%. When the cooling load is 100% or lower continuously for 30 min., the absorption freezer
32
is stopped. A condition where the cooling load is 100% or lower continuously for 30 min., is set in order to prevent repetition of an operation start and stop in a short time.
From a screen of
FIG. 10
, distributed states of the cooling loads of the absorption and turbo freezers
32
and
33
. The cooling loads of the absorption and turbo freezers
32
and
33
are distributed by controlling the three-way valves
860
and
861
in such a way as to set inlet temperatures according to the cooling loads of the respective freezers, the three-valves
860
and
861
having been controlled such that cold water inlet temperatures detected by the temperature sensors
808
and
809
provided in the cold water pipes of the respective freezers can be set equal to the target temperature 7° C. A target value of a cold water inlet temperature of the absorption freezer
32
is obtained by the following equation (3):
Tt
808
=
T
806
+
Qt
32
/(
cp×ρ×w
830
) (3)
In the equation (3), Qt
32
denotes a target amount of cooled heat (kW) of the absorption freezer; cp specified heat at constant pressure of water (kJ/kg° C.); ρ a water density (kg/m3)); w
830
a measurement value (m3)/min.) of the flow meter
830
; T
806
a measurement value (° C.) of the thermometer
806
; and Tt
808
a target value (° C.) of a cold water inlet temperature of the absorption freezer
32
. For the turbo freezer
33
, calculation is similarly carried out.
In the foregoing embodiment, the cooling loads of the turbo and absorption freezers
33
and
32
are distributed by using the three-way valves
860
and
861
. However, the cooling loads can also be distributed by setting the cold water primary pumps
342
and
343
as pumps to be driven by the inverters
400
and
431
. Now, this method is described. By the inverters
400
and
431
, cold water flow rates of the cold water primary pumps
342
and
343
are changed. A ratio of cooled heat amounts between the absorption and turbo freezers
32
and
33
is changed according to a ratio of cold water flow rates between the absorption and turbo freezers
32
and
33
. For example, to set a ratio of cooled heat amounts between the absorption and turbo freezers
32
and
33
to 2:10, frequencies of the inverters
400
and
431
are changed in such a way as to set a ratio of cold water flow rates between the cold water primary pumps
342
and
343
to 2:10. Since the use of the inverters
400
and
431
enables proper flow rates to be realized by proper motive power, running costs can be reduced.
Each of
FIGS. 12 and 13
shows optimization of air conditioner designing carried out by using the equipment designing support means
45
. By using the annual temperature and humidity fluctuation data stored in the weather database, and the relation of the cooling load to the specific enthalpy of the outside air shown in
FIG. 7
, an annular cooling load pattern is formed in step
901
. In a designing stage, a relation is set between a specific enthalpy of outside air and a cooling load is set as follows.
That is, cooling loads
973
and
974
of dry coil cooling water and production device cooling water are caused by heat generated from the production device
411
in the clean room
360
, heat from the fan unit
355
, and heat from illumination and the like. Among the amount of heat generated from the production device
411
, an amount of heat cooled by the production device cooling water is estimated to be set as the cooling load
974
of the production device cooling water. The amount of heat from the production device
411
in the clean room
360
, the amount of heat from the fan unit
355
, and the amount of heat from the illumination or the like are estimated. The cooling load
974
of the production device cooling water is subtracted from the total amount thereof to be set as the cooling load
973
of the dry coil cooling water.
In
FIG. 7
, inclination of a cooling load
975
of the introduced outside air is equivalent to a mass flow rate (kg/s) of the introduced outside air. A specific enthalpy at the point
972
where the lien
971
of the cooling load of the introduced out side air intersects the line
970
of a sum of the cooling loads
974
and
973
of the dry coil cooling water and the device cooling water is set as a specific enthalpy of air to be cooled by the cooling coil
424
of the outside air conditioner
430
.
In step
902
, a connection relation among the individual devices of the air conditioning equipment
39
is set. A designer enters the following bits of information by using an editor installed in a computer: type information for each device such as the pump, the freezer, or the temperature sensor, physical connection information indicating that cold water discharged from the pump is guided to the freezer, and control information indicating that a detected value of the temperature sensor is set equal to a set temperature as a control target value.
In step
903
, a type and the number of device are set. One air conditioning equipment is constructed by referring to the device configuration dataset registered in the device information database
24
.
FIG. 13
shows an example of such a device configuration dataset. The device configuration dataset includes data on a type of each device, and the number thereof. One to be used for the air conditioning equipment is selected from the devices registered in the device information database
24
, and entered to items of the device configuration dataset. If the device to be used is not registered in the device information database
24
, this device is newly registered in the device information database
24
.
As the price data is also stored in addition to the device characteristic data in the device information database
24
, in step
904
, initial costs are calculated for each air conditioning equipment by using this price data. Based on the annual cooling load pattern formed in step
901
, in step
905
, an optimum operation method is decided for each cooling load. Running costs when the air conditioning equipment is operated by this method for one year are calculated. As an example of the optimum operation method, an optimization algorithm of the operation plan shown in
FIG. 9
may be cited.
In step
906
, calculation is made as to maintenance contract costs, maintenance costs, insurance costs, taxes, costs for disposal, and other costs. In step
907
, calculation is made as to a total of running costs, initial costs and other costs when the air conditioning equipment is operated for the number of years decided by contract. In step
908
, total costs of the foregoing respective costs are ordered from lowest.
In step
909
, determination is made as to whether or not to change the device configuration dataset. If the device configuration dataset is changed, the process returns to step
903
. If the device configuration dataset is not changed, the process proceeds to step
910
. In step
910
, determination is made as to whether or not to change the connection relation (flow) of the air conditioning equipment. If the connection relation of the air conditioning equipment is changed, the process returns to step
902
. If not, the process returns to step
911
. In step
911
, the candidate air conditioning equipment are displayed in the lowest order of the total costs. According to the embodiment, since the calculation of the total costs is repeated by changing the flow of the air conditioning equipment or the device configuration dataset, the air conditioning equipment of low total costs can be easily constructed.
FIG. 14
shows a example of a change in consumption of power of the turbo freezer
33
with respect to the amount of cooled heat when a cooling water inlet temperature is 28° C. A line
130
indicates a power consumption characteristic measured when the turbo freezer
33
was manufactured. As a result of continuously running the turbo freezer
33
, a heat transfer tube of the evaporator is stained by a stain or the like on cooling water, causing a change in the turbo freezer
33
with time. Consequently, power consumption running record data
131
is shifted upward from the initial characteristic line
130
. Thus, by interpolating or approximating the running record data, a new power consumption characteristic line
132
is obtained. When this power consumption characteristic line
132
is largely shifted from an initial state, consideration is given to whether maintenance is performed or not. The device characteristic correcting means
43
executes such a change. Similarly, when it is determined from the running record data that a change occurred in the device characteristic data prestored for the absorption freezer
32
or the other device because of a change with time or the like, the device characteristic correction means
43
corrects the stored characteristic data.
FIG. 15
shows an example of a change in a cooling load of the cooling coil
424
with respect to a specific enthalpy of an outside air obtained by plotting the running record data. The specific enthalpy of the outside air is calculated from measurement values of the thermometer
800
and the hygrometer
850
installed in the instrument screen
300
, and a cooling load of the introduced outside air is calculated based on detected values of the temperature sensors
811
and
812
and the flow meter
832
. It can be seen that the cooling load of the introduced outside air cooled by the cooling coil has a linear relation
161
with the specific enthalpy of the outside air. This relation
161
is obtained by approximating the running record data by at least a square. This approximation equation is used for calculating the predicted value of the cooling load in step
802
S of the operation plan optimization algorithm shown in FIG.
9
. Also, it is used for replacement consideration described later.
The cooling loads
974
and
975
of the dry coil cooling water and the device cooling water shown in
FIG. 7
are substantially constant as long as no changes occur in a production volume or production equipment. Accordingly, an average value is obtained from the running record data among production systems. In the example of the air conditioning equipment shown in
FIG. 3
, the cooling load
974
of the dry coil cooling water is calculated from the detected values of the temperature sensors
814
and
816
, and the flow meter
833
. Similarly, the cooling load
975
of the production device cooling water is calculated from the detected values of the temperature sensors
820
and
821
, and the flow meter
834
. When the predicted value of the cooling load is obtained by using the running plan optimization algorithm shown in
FIG. 9
in step
802
S, if a production state is considered to be similar to that of a previous day, values of the previous day may be used for the cooling loads
974
and
97
of the dry coil cooling water and the production device cooling water.
When a highly efficient device is developed or a great change occurs from the cooling load during the designing of the air conditioning equipment, replacement of the equipment is considered according to the flow shown in FIG.
13
. Here, description is made only of a difference between replacement consideration and equipment designing.
The cooling load
975
of the introduced outside air is obtained from the drawing of the cooling load of the introduced outside air with respect to the specific enthalpy of the outside air, the example of which is shown in
FIG. 14
, prepared by the device characteristic correction means
43
. The cooling loads
974
and
973
of the dry coil cooling water and the device cooling water are obtained from the past running record data. An annual change in the temperature and humidity of the outside air is obtained from the past data on the temperature and humidity of the outside air as in the case of equipment designing. By using these values, in step
901
, an annual cooling load pattern is formed.
Total costs for the number of years set in the current equipment are calculated. In this case, initial costs are assumed to be 0. Steps
905
to
911
of
FIG. 13
are executed as in the case of equipment designing. Returning to step
902
, if changes are necessary, the flow of the air conditioning equipment is changed in step
902
, and the type of each device, and the number of devices are changed in step
903
.
If replacement is assumed, initial costs are set as costs necessary for the replacement. In step
904
, costs necessary for the replacement are calculated. Steps
905
to
911
are executed as in the case of equipment designing. When total costs in the case of replacement are lower than total costs of the current equipment, since replacement costs can be recovered in a period shorter than the number of years previously set in step
907
, the replacement is carried out.
Each of
FIGS. 16 and 17
shows a procedure when a contract is started. The service provider company
2
owns the air conditioning equipment
39
and the air conditioning equipment management controller
30
. The service provider company
2
supplies cold water to the contract company
11
, and receives payment from the contact company
11
according to the supplied amount of cold water. Accordingly, the contract company
11
can conserve energy and save costs for the air conditioning equipment without making any initial investments. In
FIG. 16
, upon receiving an order from the contract company
11
(
601
), the service provider company
2
investigates a cooling load of the contract site
1
(
602
), and obtains cooling load data (
603
). In this case, running costs of existing air conditioning equipment are investigated, and running costs per a unit amount of heat for the equipment are calculated. The service provider company
2
roughly designs air conditioning equipment (
604
), requests a manufacturing company
3
to provide information regarding a device characteristic or the like of a constituting device, and an estimate (
605
), and receives the information (
606
). The service provider company
2
negotiates a load of fund for buying the devices with a financial company
7
(
607
). In addition, the service provider company
2
negotiates contract terms for a power supply condition and a rate, a gas supply condition and a rate, and weather forecast supply condition with the power supply company
5
, the gas supply company
4
, and the weather forecast company
8
(
608
).
The service provider company
2
designs equipment in detail by using the equipment designing support means
45
, and makes contract terms (
609
). The service provider company
2
negotiates contract terms with the contract company
11
(
610
). If no agreement is reached on the contact terms, then the process returns to
605
for reexamination. If an agreement is reached on the contract terms, contracts are established (
611
, and
612
).
If the contract company
11
has existing air conditioning equipment, and parts thereof are used, the service company
2
buys a device to be used from the contract company
11
or makes a lease contract (
612
). The service provider company
2
orders air conditioning equipment to the manufacturing company
3
(
613
), and installs the air conditioning equipment
39
and the air conditioning equipment management controller
30
in the contract site
1
(
614
). Moreover, the service provider company
2
makes a load contract with the financial company
7
for payment of the air conditioning equipment
39
and the air conditioning equipment management controller
30
(
615
), and obtain a loan from the financial company
7
(
616
).
The service provider company
2
pays for the air conditioning equipment
39
and the air conditioning equipment management controller
30
to the manufacturing company
3
(
617
). If the existing air conditioning equipment is bought from the contract company
11
, payment is made to the contract company
11
. The service provider company
2
makes a power supply contract, a gas supply contract, and weather forecast supply contract with the power supply company
5
, the gas supply company
4
, and the weather forecast company
8
(
618
).
FIG. 17
shows a procedure for a normal operation. The service provider company
2
receives the running record data of the air conditioning equipment
39
from the air conditioning equipment management controller
30
installed in the contract site
1
through the network
10
. The service provider company
2
receives the weather forecast data from the weather forecast company
8
through the network
10
. Then, an operation method of lowest running costs is obtained by using the operation method optimizing means
44
. Operation plan data is prepared by using the obtained operation method (
632
).
The service provider company
2
transmits the prepared operation plan data, and time series data of the weather forecast data received from the weather forecast company to the air conditioning equipment management controller
30
of the contract site
1
. Also, the service provider company
2
notifies a operation state to the contract company
11
(
634
), the operation state including the total amount of heat for cooling, the total amount of heat for heating and the amount of used steam thus far, a rate of use, the amount of heat for cooling and the amount of heat for heating thus far, a change with time in a mass flow rate of steam and the like.
The rate of use is obtained by adding a specific charge to a fixed basic monthly rate, the specific charge being obtained by multiplying an accumulated use amount of heat for cooling or heating and an accumulated use amount of steam with unit prices. The amount of heat for cooling is a sum of the amount of heat (including latent heat during dehumidifying) obtained by cooling air introduced into the outside air conditioner
430
by the cooling coil
424
, the amount of heat obtained by cooling air in the clean room
360
by the dry coil
426
, and the amount of heat obtained by cooling the production device
411
by device cooling water. The amount of heat for heating is obtained by heating the air introduced into the outside air conditioner
430
by steam distributed in the preheating coil
421
and the reheating coil
425
. The steam use amount is the amount of steam used by the humidifier
423
.
A basic rate is set low for a contract site where annular cooling load fluctuation is small, while a basic rate is set high for a contract site where annual cooling load fluctuation is large, and a difference between an annual average cooling load and a cooling load at a peak time is large. Alternatively, a basic rate is set higher as a cooling load at a peak time is larger. Basic rates are similarly set for the amount of heated heat and the steam use amount.
Determination is made as to whether it is a rate payment day or not in step
635
. If it is not a rate payment day, the process returns to step
630
. If it is a rate payment day, then a rate is charged to the contract company
11
in step
636
. Then, the service provider company
2
receives payment from the contract company
11
in step
637
. The rate charged to the contract company
11
is a result of subtracting a land rental rate or the like from the use rate, that is, subtracting payment to the contract company
11
.
The service provider company
2
pays for the weather forecast supply rate to the weather forecast company
8
in step
638
. Then, the service provider company
2
pays for the power supply rate to the power supply company in step
639
; for the gas rate to the gas supply company in step
640
; and for the loan to the financial company
7
in step
641
.
Now, description is made of a case where the contract site
1
owns the air conditioning equipment
39
. In this case, the service provider company
2
reduces running costs by improving efficiency of the air conditioning equipment
39
of the contract site
1
, and the reduced cost amount is divided between the contract company
11
and the service provider company
2
. Running costs (yen/MJ) per a unit amount of heat before operation of the service provider company
2
is calculated by the following equation (4):
A
1
=(
B
1
+
C
1
)/
D
1
(4)
In the equation (4), A
1
denotes running costs (yen/MJ) per a unit amount of heat before the operation of the service provider company
2
; B
1
an annual gas rate (yen/year) before the operation of the service provider company
2
; C
1
an annual power rate (yen/year) before the operation of the service provider company
2
; and D
1
an annual total amount of cooled heat (MJ/year) before the operation of the service provider company
2
. The amount of cooled heat D
1
(MJ/year) is a value obtained by measuring performed by a measuring device attached before the service provider company
2
operates the air conditioning equipment. Thus, before the operation start of the service provider company
2
, the running costs Al can be accurately obtained. Instead of measuring the amount of cooled heat, estimation may be made from data owned by the contract company
11
. Since it owns various data for the other contract sites, the service provider company
2
can estimate running costs per a unit amount of heat by using data of the other contract sites similar in equipment configuration.
A reduced amount of running costs is calculated by using the following equation (5):
M
2
=
D
2
×
A
1
−(
B
2
+
C
2
+
E
2
) (5)
Here, M
2
denotes a reduced amount (yen/month) of running costs of one month; B
2
a gas rate (yen/month) of one month; C
2
a power rate (yen/month) of one month; E
2
other costs (yen/month) including depreciation and interest rates of one month; and D
2
a total amount of cooled heat (MJ/year) of one month.
The reduced amount M
2
(yen/month) of the running costs obtained as a result of the operation of the service provider company is divided between the contract company
11
and the service provider company
2
at a ratio decided by the contract. Similar calculations are made for the total amount of heated heat and the steam use amount. If an operation state is bad, the reduced amount M
2
(yen/month) of the running costs of one month becomes minus. Thus, risk burdens are decided beforehand between the contract company
1
and the service provider company
2
.
FIG. 18
shows another embodiment of the invention. This embodiment is different from the embodiment shown in
FIG. 3
is that cooling water of the production device
411
, and cooling water of the dry coil
427
disposed in the clean room
360
are heat-exchanged with cooing water circulated in the cooling towers
312
and
313
. That is, the cooling water distributed through the dry coil
427
is passed from the valve
866
through the temperature sensor
816
, and heat-exchanged with the cooling water circulating in the cooling tower
312
by the heat exchanger
457
to be cooled. The cooled water is passed from the temperature sensor
815
through the dry coil cooling water pump
345
, and sent to the dry coil cooling water heat exchanger
455
. A three-way valve
867
is provided in the midway of a pipe for the cooling water circulating in the cooling tower
312
, and one side of the three-way valve
867
is connected to a bypass pipe of the heat exchanger
457
. In the cooling water circulation pipe of the cooling tower
312
, a pump
346
and a temperature sensor
817
for detecting a cooling water outlet temperature are provided.
Cooling water having cooled the production device
411
and held in the production device cooling water tank
461
is guided to the cooling tower
313
by a pump
348
. The following elements are provided in the pipe of cooling water circulating in the cooling tower
313
: a temperature sensor
818
for detecting a temperature out of the cooling tower
313
; a three-way valve
868
located downstream of this temperature sensor, and connected to a bypass pipe bypassing the cooling tower
313
; and a temperature sensor
819
located downstream of the three-way valve for detecting a temperature of cooling water. The three-way valves
867
and
869
are controlled such that temperatures detected by the temperature sensors
816
and
819
can be equal to set temperatures. In order to prevent temperatures of cooling water in outlets of the cooling towers
312
and
323
from becoming too low, fans of the cooling towers
312
and
313
are subjected to ON/OFF control or rotational speed control according to detected values of the temperature sensors
817
and
818
.
In the configuration of the embodiment, the number of cooling towers is increased compared with the case of the configuration of FIG.
3
. However, cooling capability can be accordingly increased, making it possible to deal with a sudden demand increase.
FIG. 19
shows a relation between a wet bulb temperature of outside air and an amount of cooled heat detected by the cooling towers
312
and
313
. Operation plans are made for the cooling towers
312
and
313
based on changes in a temperature and humidity of the outside air and, based on annual temperature and humidity changes in the contract site, air conditioning equipment is designed in such a way as to reduce total costs.
FIG. 20
shows a relation between the wet bulb temperature of the outside air and running costs per a unit amount of heat for the cooling towers
312
and
313
. The running costs include power consumption of the cooling tower
312
and a circulation pump. As compared with running costs per a unit amount of heat for the absorption and turbo freezers
32
and
33
shown in
FIG. 5
, running costs per a unit amount of heat for the cooling towers
312
and
313
may be lower depending on a wet bulb temperature of the outside air. In such a case, the cooling towers
312
and
313
are operated to reduce running costs.
To select operation methods of the cooling towers
312
and
313
, a combination of an operation and a stop for each of the cooling towers
312
and
313
is made. An optimum operation plan is made according to the operation flow shown in FIG.
9
. Specifically, an example when a cooling load X of the freezer becomes 100% or lower is shown.
In the case of X≦100,
(11) X
1
=X, X
2
=0, the cooling towers
312
and
313
are operated.
(12) X
1
=0, X
2
=X, the cooling towers
312
and
313
are operated.
(13) X
1
=X, X
2
=0, the cooling tower
312
is operated, but the cooling tower
313
is stopped.
(14) X
1
=0, X
2
=X, the cooling tower
312
is operated, but the cooling tower
313
is stopped.
(15) X
1
=X, X
2
=0, the cooling tower
312
is stopped, but the cooling tower
313
is operated.
(16) X
1
=0, X
2
=X, the cooling tower
312
is stopped, but the cooling tower
313
is operated.
(17) X
1
=X, X
2
=0, the cooling towers
312
and
313
are stopped.
(18) X
1
=0, X
2
=X, the cooling towers
312
and
313
are stopped.
The operations of the cooling towers
312
and
313
are decided depending on a wet bulb temperature of the outside air. Whether the cooling towers
312
and
313
cane operated or not is decided based on device characteristic data. When the cooling towers
312
and
313
can be operated, amounts of heat to be cooled by the cooling towers
312
and
313
are obtained. A value obtained by subtracting the amount of heat cooled by the cooling towers
312
and
313
from an entire cooling load is set as a cooling load X of the freezer, and target amounts of cooled heat are set for the absorption and turbo freezers
32
and
33
.
FIG. 21
shows a relation between a dew-point temperature and an amount of cooled heat of the cooling tower when a cooling tower outlet temperature is 14° C. A line
140
indicates a characteristic line during manufacturing; and a line
141
a line connecting running record data. When the running record data is shifted by a predetermined amount from the initial characteristic line
140
, the characteristic line is corrected to the line
141
obtained from the running record data.
Now, description is made of another method for calculating a specific charge by referring to FIG.
22
.
FIG. 22
shows a cold water temperature, and a unit price per cold water weight. As a cold water temperature is lower, a cold water unit price is set higher. A reason is that greater energy is necessary for lower temperature cold water. Regarding cooling loads of the cold water coil
424
, the dry coil
426
, and the production device
411
, a specific charge is calculated by the following equation (6):
MM
=(
MM
1
−
MM
2
)×
WW
/60
×TI×ρ
(6)
In the equation (6), MM denotes a specific charge (yen) of cold water; MM
1
a unit price (yen/kg) corresponding to a temperature of supplied cold water; MM
2
a unit price (yen/kg) corresponding to a temperature of returned cold water; WW a flow rate (m3)/min.); TI time (s); and ρ a water density (kg/m3)).
Now, as a modified example of the embodiment shown in
FIG. 18
, a case of increasing the respective numbers of cooling towers
310
and
311
is described. In addition to the cooling towers
310
and
311
, cooling towers
312
and
313
are increased in number. Accordingly, cold water primary pumps
342
and
343
, and cooling water pumps
340
and
341
are also increased in number. Simple combinations lead to an increase in the number of combinations. However, such a number of combinations can be reduced by considering a characteristic of air conditioning equipment.
For example, when a cooling load of the freezer is 280%, by setting the number of freezers to be operated to 4 or more, power supplied to the cold water primary pumps
342
and
343
, the cooling water pumps
340
and
341
, and the cooling towers
310
and
311
to be operated is increased. However, running costs can be reduced by operating only three of the freezers. Accordingly, an operation combination of freezes is set on the assumption that the three freezers are operated. As a result, it is possible to reduce the number of combinations.
As apparent from the foregoing, according to the present invention, in the air conditioning equipment operation system provided with the plurality of freezers, since the air conditioning equipment is operated by considering a partial load characteristic of each freezer, and a fuel/power rate, an operation is possible, where running costs with respect to a load can be reduced. It is also possible to realize the air conditioning equipment operation system, where total costs including initial and running cots are reduced. Furthermore, it is possible to realize the operation system capable of supplying low-cost cold water.
It should be further understood by those skilled in the art that the following description has been made on embodiments of the invention and that various changes and modifications may be made in the invention without departing from the spirit of the invention and the scope of the appended claims
Claims
- 1. An air conditioning equipment operation system in which air conditioning equipment provided in a contract site is operated by a service provider company, wherein the service provider company has a control server, said system comprising a device information database storing a device characteristic data of an air conditioner constituting the air conditioning equipment, a fuel or electricity rate database storing rate data of at least one of gas, oil and electric power, and an air conditioning equipment simulator for obtaining a partial load factor, and at least one of power consumption and fuel consumption during partial load running by using the device characteristic data and a cycle simulator, and for calculating running costs from the obtained power consumption and/or fuel consumption by using the rate data, wherein the contract site includes an air conditioning equipment management controller provided to manage and control the air conditioning equipment; the control server and the air conditioning equipment management controller are connected to each other through a network; the control server predicts a cooling load from predictable time series data on a temperature and humidity of outside air by referring to the device information database to make an operation plan of the air conditioner; and the air conditioning equipment management controller operates the air conditioner in accordance with the operation plan; andwherein the air conditioning equipment simulator calculates running costs for each operation of the air conditioner, and makes operation plan data by an operation method having lowest running costs among the calculated running costs.
- 2. The air conditioning equipment operation system according to claim 1, wherein the air conditioning equipment includes absorption and turbo freezers, and the air conditioning equipment simulator selects full or partial loads of the freezers in accordance with a set amount of heat for cooling of the absorption and turbo freezers, and calculates running costs in this case.
- 3. The air conditioning equipment operation system according to claim 1, wherein the air conditioning equipment includes a cooling tower, and the air conditioning equipment simulator calculates running costs in accordance with the operation/stop of the cooling tower.
- 4. The air conditioning equipment operation system according to claim 1, wherein the control server predicts a cooling load from prediction data on a temperature and humidity of an outside air purchased from a weather forecast company; and the air conditioning equipment simulator sets an operation method of the air conditioning equipment in the air conditioning equipment management controller through a web based on the predicted cooling load.
- 5. The air conditioning equipment operation system according to claim 1, wherein said system comprises means for detecting the temperature and humidity of the outside air and means for detecting a cooling load of the air conditioning equipment, an equation of relation between the cooling load and the temperature and humidity of the outside air is obtained from the temperature and humidity of the outside air and the cooling load detected by the detecting means to predict a cooling load by using a equation of this relation.
- 6. The air conditioning equipment operation system according to claim 1, wherein the air conditioning equipment provided in the contract site includes a plurality of independently operable air conditioning equipment, and wherein the air conditioning equipment simulator provides simulation for a plurality of different operational scenarios using mutually differing operational combinations and/or cycles of ones of the plurality of independently operable air conditioning equipment, and calculates running costs for each different operational scenario.
- 7. The air conditioning equipment operation system according to claim 6, wherein the air conditioning equipment simulator provides simulation for at least three different operational scenarios.
- 8. The air conditioning equipment operation system according to claim 1, wherein the air conditioning equipment simulator is provided at a service provider company facility which is different from a facility where the air conditioning equipment is provided.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2001-317570 |
Oct 2001 |
JP |
|
US Referenced Citations (13)
Foreign Referenced Citations (3)
Number |
Date |
Country |
A-7-139761 |
May 1995 |
JP |
A-8-86533 |
Apr 1996 |
JP |
9-026804 |
Jan 1997 |
JP |