JP5975253B2 - Air conditioning operation control system - Google Patents

Description

  The present invention relates to an air conditioning operation control system for a regenerative air conditioning facility.

  As is well known, heat storage air conditioning equipment equipped with a heat storage tank is based on the fact that the heat storage operation is performed on the heat storage tank at low loads such as at night, and the heat storage tank's stored heat storage is used at high loads such as during the daytime. Since it can be efficiently operated as a whole and can contribute to energy saving, it has been widely used as an air conditioning facility for buildings, factories, and the like. As shown in Fig. 2, there is also a proposal for an advanced control system for learning and predicting outside air conditions, building use conditions, etc. and performing optimum operation.

JP 2006-78009 A

  Although the control system as described above is effective in efficiently operating the regenerative air conditioning equipment, it is a sophisticated and expensive system that requires complex software and hardware. Introducing it into equipment has been difficult to achieve because it may be difficult in terms of cost.

  In view of the above circumstances, an object of the present invention is to provide a simple and effective air conditioning operation control system that enables efficient operation of a regenerative air conditioning facility.

The present invention is an air conditioning operation control system for a regenerative air conditioning facility, and performs air conditioning operation according to the load by controlling the number of heat source units while using the stored heat storage in the heat storage tank within the air conditioning operation time. An air conditioning operation mode to be performed and a heat storage operation mode in which the heat storage device performs a heat storage operation with respect to the heat storage tank outside the air conditioning operation time. In the air conditioning operation mode, the heat storage tank has priority to use the stored heat storage. However, the load flow priority mode for controlling the number of the heat source units according to the load at that time, and maintaining the retained heat amount so that the retained heat amount of the heat storage tank becomes almost zero at the end of the air conditioning operation mode. preferentially to enable setting the residual heat storage amount priority mode for controlling the number of the heat source apparatus, the heating of the thermal storage operation mode, and in the air-conditioning operation mode, said plurality of heat sources The performed count control of the plurality of heat source apparatuses while full load operation, and changes the operation stop order of the plurality of heat source apparatuses each of units control of the heat source apparatus.
Moreover, in this invention, it is preferable to ensure the fixed time space | interval for the stage increase or decrease in the number control of each heat source machine.

In the air conditioning operation control system of the present invention, when operating in the air conditioning operation mode, the load flow rate priority mode for controlling the number of heat source units according to the load, and the number control of the heat source units giving priority to the maintenance of the remaining heat amount of the heat storage tank. It is possible to operate each heat source unit at full load with high efficiency by setting the remaining heat storage priority mode to perform the operation, and to effectively use up the stored heat storage in the heat storage tank at the end of the air conditioning operation mode. Control is possible and the most efficient air conditioning operation is possible.
The air-conditioning operation control system of the present invention is a simple and inexpensive system that does not require complicated software, hardware, and a control mechanism, and can be widely applied to general heat storage type air-conditioning equipment in general.

BRIEF DESCRIPTION OF THE DRAWINGS The embodiment of the air-conditioning operation control system of this invention is shown, and is a figure which shows the driving | running state by the thermal storage operation mode at the time of the schematic structure of an air-conditioning installation and air_conditioning | cooling. It is a figure which shows the driving | running state by the air-conditioning driving | operation mode (load flow priority mode and residual heat storage priority mode) at the time of cooling. It is a figure which shows the driving | running condition by the thermal storage operation mode at the time of heating. It is a figure which shows the driving | running state by the air-conditioning operation mode (load flow rate priority mode and residual heat storage priority mode) at the time of heating. It is explanatory drawing about the load flow rate priority mode in air-conditioning operation mode. It is explanatory drawing about the remaining heat amount priority mode in air-conditioning operation mode. It is a figure which shows an example of the operation schedule of the heat source machine at the time of cooling.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 4 are diagrams schematically showing a schematic configuration of the heat storage type air conditioning equipment to which the air conditioning operation system of the present embodiment is applied and its operation status according to modes (in FIGS. 1 to 4, operation is performed in each mode). Only the elements that are marked are marked with bold lines).

  As shown in FIGS. 1 to 4, the heat storage type air conditioner of the present embodiment includes a plurality of (four in the illustrated example) heat source units 1 and heat storage tanks 2. Is a turbo chiller 1a (indicated as R-1 in the figure) as a cooling-only heat source unit as the heat source unit 1, and an HP chiller 1b (air heat source heat pump type chilling unit as a cooling / heating heat source unit). In this case, CR-1-1, CR-1-2, and CR-1-3 are used, and the heat storage tank 2 is a vertical container.

In the figure, reference numeral 3 is a supply header, 4 is a return header, 5 is a primary pump (a cold water primary pump 5a for the turbo chiller 1a, and a cold / hot water primary pump 5b for the HP chiller 1b), and 6 is 2. A piping system for circulating cold / hot water (cold water at the time of cooling and hot water at the time of heating) between the heat source units 1, the heat storage tank 2, and the load 7 such as an air conditioner as a whole. Is configured.
Of course, there are various sensors and control valves for detecting the flow rate, pressure, water temperature and other conditions every moment, and switching valves, bypass pipes and other accessories for switching the piping route. Of course, an accessory device and a control system for automatically controlling the entire device are provided, but illustration of these elements is omitted except for a part thereof.

  In the air conditioning equipment of this embodiment, as shown in FIGS. 1 to 4, the cold water temperature at the time of cooling is set to the forward water temperature 7 ° C. to the return water temperature 17 ° C., and the hot water temperature at the time of heating is set to the forward water temperature 50 ° C. After the return water temperature is set to 40 ° C., the piping path to the heat storage tank 2 is switched by the valve operation in the figure during cooling and heating, as in the case of normal heat storage air conditioning equipment, and during cooling and heating In any of the above, heat storage operation is performed to store heat in the heat storage tank 2 outside the air-conditioning operation time (generally in the non-operating time zone from night to midnight), and within the air-conditioning operation time (generally daytime operation time) Basically, the air conditioning operation for operating each heat source unit 1 according to the load is performed while using the stored heat storage of the heat storage tank 2.

Specifically, as shown in FIG. 1, at the time of cooling (for example, 22:00 to 8:00 in the illustrated example), cold water is supplied from the turbo chiller 1a, and the heat storage tank 2 at that time is supplied. The operation is performed in the “heat storage operation mode” for replacing the cold water of 17 ° C. held by the inside with the cold water of 7 ° C. and storing the cold water of 7 ° C. in the full heat storage water 2 in a full state.
In addition, as shown in FIG. 2, during the daytime during cooling (for example, 8:00 to 22:00 in the illustrated example), 7 ° C. cold water held in the heat storage tank 2 is supplied to each load 7 (this The inside of the heat storage tank 2 is replaced with cold water of 17 ° C.) and 7 ° C. prepared by operating the heat source unit 1 (turbo refrigerator 1a and / or HP chiller 1b) according to the load by controlling the number of units. The operation in the “air conditioning operation mode” for directly supplying the cold water to each load 7 is performed.

On the other hand, as shown in FIG. 3, by supplying hot water from the HP chiller 1b to the heat storage tank 2 at night time during heating (for example, 22:00 to 8:00 as in the case of cooling), At the time, the 40 ° C. warm water held in the heat storage tank 2 is replaced with the 50 ° C. warm water, and the operation in the “heat storage operation mode” for storing the 50 ° C. warm water in the full state in the entire heat storage tank 2 is performed. .
In addition, as shown in FIG. 4, during the daytime during heating (for example, in the illustrated example, from 8:00 to 22:00 as in cooling), hot water of 50 ° C. held in the heat storage tank 2 is supplied to each load 7. Supplying this (the inside of the heat storage tank 2 is replaced with 40 ° C. warm water), and the HP chiller 1b is operated by unit control according to the load, and 50 ° C. hot water prepared thereby is supplied to each load 7. Operation in “air-conditioning operation mode” for direct supply.

In the above-mentioned “heat storage operation mode”, the operation of the heat source unit 1 is controlled so that the heat storage is completed at the end of the operation, but in order to perform the heat storage operation with high efficiency, each heat source unit 1 is possible. Therefore, it is preferable to avoid partial load operation (low load operation) with low efficiency as full load operation.
For that purpose, at the time of cooling, as shown in FIG. 1, one turbo refrigerator 1a may be operated at full load to control the operation time. Further, during heating, as shown in FIG. 3, the number of chillers 1b may be controlled as necessary while operating each HP chiller 1b at full load. In this case, the start / stop order of each HP chiller 1b is appropriately rotated. It is good to change each time by the program.

As described above, in the present invention, the operation in the “heat storage operation mode” is performed outside the air conditioning operation time, and the operation in the “air conditioning operation mode” is performed within the air conditioning operation time. At the time of the “air conditioning operation mode” at the time, either “load flow priority mode” or “residual heat storage priority mode” can be selectively set.
Specifically, as shown in FIG. 2 and FIG. 4, the relative time out of the time zone from 8:00 to 22:00 in which the operation is performed according to the “air-conditioning operation mode” at both the cooling time and the heating time. During periods of high load (for example, between 8:00 and 15:00 in the illustrated example), operation is performed in the “load flow priority mode” and other periods of relatively low load (for example, FIG. In the example shown, between 15:00 and 22:00), the operation in the “remaining heat storage priority mode” is performed.

  In the present invention, the “load flow priority mode” means that the stored heat in the heat storage tank 2 is used preferentially as shown in FIG. Thus, the number of heat source devices 1 is controlled so that the heat source devices 1 are stepped down sequentially.

As a specific example of the “load flow rate priority mode”, as shown in FIG. 5A, for example, as shown in FIG. 5A, each heat source unit is operated as a cooling operation using only the stored stored water until the load flow rate is 2045 L / min. The turbo chiller 1a is operated when the load flow rate becomes 2045L / min without operating, and any one of the three HP chillers 1b is operated when the load flow rate becomes 2578L / min. When the load flow rate becomes 3111L / min, the second HP chiller 1b is operated, and when the load flow rate becomes 3644L / min, the third HP chiller 1b is operated. It becomes a driving state.
Conversely, when the load decreases from the above-mentioned full cooling operation state, when one of the load flow rates reaches 3111 L / min, one of the HP chillers 1b is stopped and the load flow rate becomes 2578 L / min. At that time, the second HP chiller 1b is stopped. When the load flow rate reaches 2045L / min, the third HP chiller 1b is stopped. When the load flow rate reaches 1512L / min, turbo refrigeration is performed. The machine 1a is also stopped and the cooling operation using only the heat storage water is performed.

Similarly, at the time of heating, for example, as shown in FIG. 5B, until the load flow rate is 1066 L / min, each heat source unit 1 is not operated as a heating operation using only the stored heat storage water, and the load flow rate is 1066 L. When one of the three HP chillers 1b is operated at the time of reaching / min, the second HP chiller 1b is operated at a load flow rate of 1599L / min, and the load flow is 2132L. When the time reaches / min, the third HP chiller 1b is operated, and the state becomes the full heating operation state.
Conversely, when the load decreases from the above-mentioned full heating operation state, when one of the load flow rates reaches 1599 L / min, one of the HP chillers 1b is stopped and the load flow rate becomes 1066 L / min. At that time, the second HP chiller 1b is stopped, and when the load flow rate becomes 533 L / min, the third HP chiller 1b is also stopped to perform the heating operation using only the heat storage water.

On the other hand, the “remaining heat storage amount priority mode” in the present invention means that the retained heat amount at that time is set to a target value so that the retained heat amount in the heat storage tank 2 becomes substantially zero at the end of the “air conditioning operation mode”. The number of heat source units 1 is controlled with priority given to maintenance.
That is, since the remaining heat storage amount of the heat storage tank 2 gradually decreases during the “air-conditioning operation mode” and is preferably zero at the end of the heat storage tank 2, the remaining heat storage amount at each time point is appropriately maintained. The number of heat source devices 1 is controlled so that the remaining heat storage amount and the heat storage target at that time are compared and compensated for each moment. Specifically, as shown in FIG. 6, when the difference between the heat storage target and the current heat storage amount is large, a predetermined number of each heat source unit 1 is operated, and each heat source unit 1 is gradually reduced as the difference decreases. It is sufficient to control the number of units.

In both the “load flow priority mode” and the “remaining heat storage priority mode”, the heat source units 1 are all fully loaded as much as possible as in the “heat storage operation mode”. It is preferable to avoid partial load operation (low load operation) with low efficiency.
Moreover, it is preferable to change the operation stop order of the three HP chillers 1b each time by the rotation program.
Further, the increase or decrease of the number of heat source units 1 when controlling the number of the heat source units 1 ensures frequent intervals in a short time by securing an interval of a certain time (for example, about 15 minutes) in order to keep the load stable. It is preferred to limit the repetition of steps.
Similarly, since it is not preferable to frequently start and stop each heat source unit 1 in a short time, it is preferable to limit restart until a certain time (for example, about 15 minutes) elapses after the stop.

FIG. 7 shows an example of a specific operation schedule of each heat source machine 1 when the operation is performed by the operation control system of the present embodiment.
In the case of the illustrated example, in the time zone from 22:00 to 8:00, the thermal storage operation is performed by operating the turbo refrigerator 1a at full load by the “thermal storage operation mode”. Prepare for operation in “air-conditioning operation mode” from 8:00.
At 8:00, operation in the `` load flow priority mode '' was started, and it was initially operated using only the stored heat storage water. After that, each of the stored heat storage water was used to compensate for the shortage according to the load. The number of heat source units 1 is controlled (in the example shown, the full-load operation of the turbo chiller 1a is started at 9:00, and the full-load operation of three HP chillers 1b is started at around 10:30. ing).
After 15:00, it shifts to the “Residual heat storage priority mode”. In the example shown in the figure, two HP chillers 1b first stop, and then one HP chiller 1b stops. Refrigerator 1a is also stopped, and the transition is to run only with the stored heat storage water. At 20:00, the heat storage water is used up and the operation in “air-conditioning operation mode” (“residual heat storage priority mode”) is stopped. Prepare for the start of operation in “heat storage operation mode” from 00.

  As described above, according to the present invention, the “load flow priority mode” and the “remaining heat amount priority mode” are set during the operation in the “air-conditioning operation mode”, and each heat source unit 1 is fully loaded in each mode. By operating, the most efficient and optimal operation is possible.

That is, in this type of conventional control system, priority is given to compensation when the remaining heat storage amount becomes a predetermined amount or less without performing an operation corresponding to the above-described “load flow priority mode”. Thus, the heat source machine is immediately operated, and the operation is frequently repeated as a partial load operation (low load operation), and hence the operation efficiency is inevitably lowered.
Further, when the heat source machine is operated in such a partial load, the return water temperature deviates from the design value (for example, during cooling, the return temperature does not increase to the design value of 17 ° C., but becomes about 14 ° C. ) Therefore, it is impossible to maintain an appropriate design temperature difference of 10 deg. As a result, a clear temperature stratification is not formed in the heat storage tank 2 and the heat storage efficiency is lowered, and the remaining heat storage amount is accurately measured. Various problems such as being unable to do so have also occurred.

On the other hand, in the present invention, a time zone in which the remaining heat storage amount is intentionally restricted is set by setting the “load flow priority mode”, and the heat source unit 1 is operated at all until a certain load is generated in that mode. It is assumed that the operation is performed only by using the stored heat storage water without any operation. One of the heat source units 1 is operated at full load only when a certain load is generated, and the desired number of units is increased as the load increases. The number control is performed while operating each of the heat source devices 1 at full load.
As a result, each heat source unit 1 can be operated with high efficiency, and the water temperature difference between the return and return can be maintained at 10 deg as designed, so that the temperature stratification in the heat storage tank 2 is disturbed. A decrease in heat storage efficiency can also be prevented, and as a result, excellent high-efficiency operation is possible as a whole, which can greatly contribute to energy saving and running cost reduction.

Of course, by operating in the “remaining heat storage amount priority mode” as usual after the above “load flow priority mode”, all of the stored heat storage amount is effectively used up to the end of the “air conditioning operation mode”. Thus, the remaining heat storage can be made zero.
Moreover, the operation control system of the present invention can be constructed as a simple and inexpensive system that does not require complicated advanced software, hardware, and control mechanisms in order to perform such optimal control. It can be widely applied to air conditioning equipment in general.

  Although the embodiment of the present invention has been described above, the above embodiment is merely a preferred example, and the present invention is not limited to the above embodiment, and the entire regenerative air conditioning facility exemplified as the above embodiment. Configuration, type and number of heat source units and heat storage tanks, water temperature and flow rate, time zone setting for each mode, timing setting for switching from "load flow priority mode" to "residual heat storage priority mode", and other conditions and specifications Can be arbitrarily changed without departing from the scope of the present invention, taking into consideration the usage and operating conditions of the buildings and structures to which the present invention is applied, actual fluctuations in the heating and cooling load, and other conditions. Needless to say.

1 Heat source machine 1a Turbo refrigerator 1b HP chiller (Air heat source heat pump chilling unit)
2 Heat storage tank 3 Supply header 4 Ritan header 5 Primary pump 5a Cold water primary pump (for turbo refrigerator)
5b Cold / hot water primary pump (for HP chiller)
6 Secondary pump 7 Load (air conditioner, etc.)

Claims (2)

An air-conditioning operation control system for a regenerative air conditioner,
An air conditioning operation mode in which the air conditioning operation according to the load is performed by controlling the number of heat source units while using the stored heat storage in the heat storage tank within the air conditioning operation time,
Set a heat storage operation mode for performing a heat storage operation for the heat storage tank by the heat source machine outside the air conditioning operation time,
In the air conditioning operation mode, the load flow priority mode for controlling the number of the heat source units according to the load at that time while preferentially using the stored heat stored in the heat storage tank, and at the end of the air conditioning operation mode, It is possible to set a residual heat quantity priority mode in which the number of the heat source units is controlled in preference to the maintenance of the retained residual heat quantity so that the retained residual heat quantity of the heat storage tank becomes almost zero,
In heating in the heat storage operation mode and in the air conditioning operation mode, performing the number control of the plurality of heat source units while operating the plurality of heat source units at full load,
An air conditioning operation control system, wherein the operation stop order of the plurality of heat source units is changed every time the number of heat source units is controlled.   The air-conditioning operation control system according to claim 1, wherein a certain time interval is secured for the increase or decrease in the number control of the heat source units.

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