WO2016002008A1

WO2016002008A1 - Air conditioning system

Info

Publication number: WO2016002008A1
Application number: PCT/JP2014/067559
Authority: WO
Inventors: 邦彰鳥山
Original assignee: 三菱電機株式会社
Priority date: 2014-07-01
Filing date: 2014-07-01
Publication date: 2016-01-07

Abstract

An air conditioning system according to the present invention includes one or more air conditioner groups (1) and a central control device (100). The air conditioner group (1) has a refrigerant circuit formed by connecting, by pipe, an outdoor unit (10) having a compressor (12), of which the operating frequency can be adjusted as desired, and an indoor unit (20) for air-conditioning of a space to be air-conditioned. The central control device (100) includes: a storage unit (120) for storing, as data, the operating frequency of the compressor (12) included in the outdoor unit (10) in each air conditioner group (1); and a control unit (110) for determining the outdoor unit (10) to be stopped such that the operating frequency of the compressor (12) included in the outdoor unit (10) of the air conditioner group (1) being operated approaches the maximum efficiency, on the basis of the data stored in the storage unit (120), and the relationship between the operating frequency of the compressor (12) included in the outdoor unit (10) in each air conditioner group (1) and the energy efficiency thereof. With the above-mentioned arrangement, since the control unit of the central control device determines the outdoor unit to be stopped, loads on air conditioning can be dispersed, so that a compressor being driven at an operating frequency lower than the operating frequency for the maximum efficiency can be driven at the operating frequency for the maximum efficiency or at an operating frequency close thereto, thereby enabling efficient operation of the entire air conditioning system.

Description

Air conditioning system

The present invention relates to an air conditioning system and the like. In particular, the present invention relates to a system control device.

For example, there is an air conditioner having a compressor that can change the capacity by performing inverter control or the like and arbitrarily changing the operating frequency (driving frequency). Then, at a specific operating frequency, the relationship between the operating frequency and the efficiency at which the energy efficiency (hereinafter referred to as efficiency) related to the operation of the air conditioner represented by COP (Coefficient of Performance) etc. is maximized. There is an air conditioning system that has an efficiency curve characteristic that is shown and a capacity curve that shows a relationship in which the air conditioning capacity increases as the operating frequency increases, and performs control based on these characteristics.

In such an air conditioning system, there is a system in which an operation at a specific operating frequency at which the efficiency in the efficiency curve characteristic has a maximum value is a basic state in the energy saving control time zone. If it is determined that the capacity is insufficient from the deviation between the set temperature of the space (air-conditioned space) to be air-conditioned and the room temperature, control is performed to increase the operating frequency of the air-conditioning apparatus and increase the cooling / heating capacity. By performing such control, a desired energy saving effect can be obtained while maintaining the comfort of the air-conditioned space (see, for example, Patent Document 1).

JP 2012-247100 A (FIG. 1)

However, in the conventional air conditioning system as described in Patent Document 1, for example, during the period when the ability of the air conditioning apparatus is not insufficient, such as in spring and autumn, the operation is performed under the maximum efficiency condition which is the basic state. Doing so can lead to overcapacity. For this reason, there is a high possibility that air conditioning will be excessively effective. In addition, because control is performed on the premise of an air-conditioned space where the air conditioning system capacity is insufficient as a whole, the air conditioning system has a sufficiently high capacity, such as a space with a relatively low air conditioning load even in summer or winter. In this case, it may not be possible to perform control that satisfies the conditions.

The present invention has been made to solve such a conventional problem, and can efficiently perform air conditioning in an air-conditioned space without causing an excessive effect (excess supply of capacity) of the air conditioning apparatus. Provided is a control device for an air conditioning system.

The air conditioning system of the present invention includes one or a plurality of air conditioning systems having a refrigerant circuit configured by connecting an outdoor unit having a compressor capable of arbitrarily changing an operating frequency and an indoor unit performing air conditioning of a target space. Storage unit for storing the operating frequency of the compressor of the outdoor unit in each air conditioner group as data, and the relationship between the operating frequency and energy efficiency of the compressor of the outdoor unit of each air conditioner group Based on the data stored in the unit, the outdoor unit stop determination process is performed to determine the outdoor unit to be stopped so that the compressor of the outdoor unit of the operating air conditioner group approaches the maximum operating frequency. And a centralized control device having a control unit.

According to the present invention, since the control unit of the central control device determines the outdoor unit to be stopped, the compressor that distributes the air conditioning load and is driven at an operation frequency lower than the maximum efficiency operation frequency. Can be driven at an operating frequency with the maximum efficiency or an operating frequency close thereto, and the air conditioning system as a whole can be operated efficiently. For this reason, energy saving etc. can be achieved.

It is a figure which shows the structure of the air conditioning system centering on the centralized control apparatus 100 which concerns on Embodiment 1 of this invention. It is a figure which shows the detail of a structure of the air conditioning system which concerns on Embodiment 1 of this invention. It is a figure which shows the flowchart which concerns on control of the air-conditioned space which the centralized control apparatus 100 which concerns on Embodiment 1 of this invention performs. It is a figure which shows the flowchart which concerns on the outdoor unit stop determination process which concerns on Embodiment 1 of this invention. It is a figure which shows the relationship between the operating frequency and efficiency of the compressor 12 at the time of the air_conditionaing | cooling operation which concerns on Embodiment 1 of this invention. It is a figure which shows the relationship between the operating frequency and efficiency of the compressor 12 at the time of the heating operation which concerns on Embodiment 1 of this invention. It is a figure which shows the relationship between the operating frequency and efficiency of the compressor 12 which the outdoor unit 10 before the outdoor unit stop determination process which concerns on Embodiment 1 of this invention has. It is a figure which shows the relationship between the operating frequency and efficiency of the compressor 12 when the compressor 12 which the one outdoor unit 10 which concerns on Embodiment 1 of this invention has stopped. It is a figure which shows the flowchart which concerns on the compressor stop determination process which concerns on Embodiment 2 of this invention.

Hereinafter, an air conditioning system according to an embodiment of the invention will be described with reference to the drawings. Here, in FIG. 1 and the following drawings, the same reference numerals denote the same or corresponding parts, and are common to the whole text of the embodiments described below. And the form of the component represented by the whole specification is an illustration to the last, Comprising: It does not limit to the form described in the specification. In particular, the combination of the components is not limited to the combination in each embodiment, and the components described in the other embodiments can be applied to another embodiment. Furthermore, when there is no need to distinguish or identify a plurality of similar devices that are distinguished by subscripts, the subscripts may be omitted.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration of an air conditioning system centering on a centralized control device 100 according to Embodiment 1 of the present invention. In the present embodiment, it is assumed that eight air conditioner groups of air conditioner group 1a to air conditioner group 1h perform air conditioning in one air-conditioned space. Here, the number of air conditioner groups is not limited to eight, and can be increased or decreased in accordance with the size of the air-conditioned space. Since this embodiment is related to the control of the air conditioning system, FIG. 1 shows the connection relationship regarding the control (communication) system.

First, the air conditioner group 1a to the air conditioner group 1h will be described. Each air conditioner group 1 has at least one outdoor unit 10 and one indoor unit 20. In the present embodiment, the air conditioner group 1 is a control unit (control group) performed by the centralized control device 100, and performs air conditioning control for each air conditioner group 1.

FIG. 2 is a diagram showing details of the configuration of the air-conditioning system according to Embodiment 1 of the present invention. As shown in FIG. 2, each air conditioner group 1 of the present embodiment has one outdoor unit 10 and two indoor units 20. One outdoor unit 10 (10a to 10h) and two indoor units 20 (20a-1 to 20h-2) are connected by a refrigerant pipe (not shown) to constitute a refrigerant circuit. Air conditioning capacity (heat) is supplied by circulating the refrigerant in the refrigerant circuit, and air conditioning is performed by heating or cooling the air in the air-conditioned space. Here, in FIG. 2, each air conditioner group 1 is composed of one outdoor unit 10 and two indoor units 20, but the number of outdoor units 10 and indoor units 20 is particularly limited. Not what you want. The number of outdoor units 10 and indoor units 20 in each air conditioner group 1 may not be the same.

The outdoor unit 10 includes devices such as a compressor 12 and an outdoor heat exchanger (not shown), and transports the generated heat to the indoor unit 20 using a refrigerant. The outdoor unit control device 11 controls the outdoor unit 10. In addition, the outdoor unit control device 11 communicates with the central control device 100 and the indoor unit control device 21 included in the indoor unit 20, for example, data on the operating frequency of the compressor 12 and an operation state in a signal sent from the indoor unit 20. A signal including the data (control value data) is sent to the centralized control device 100.

The indoor unit 20 includes devices such as an indoor heat exchanger and a throttle device (expansion valve), and heat-exchanges heat from the outdoor unit 10 with air in the air-conditioned space, and heats and cools the air for air conditioning. I do. Moreover, it has the indoor unit control apparatus 21 which controls the indoor unit 20 based on the instruction | indication from the centralized control apparatus 100 by communication with the outdoor unit control apparatus 11. FIG. As further described above, the indoor unit control device 21 sends a signal including control value data to the centralized control device 100 via the outdoor unit control device 11. Here, in the present embodiment, for example, the temperature difference between the ambient temperature of the indoor unit 20 (the temperature of the area where the air conditioner group 1 air-conditions in the air-conditioned space; hereinafter referred to as room temperature) and the set temperature is controlled. Value. However, the data relating to the operation state in the signal sent from the indoor unit 20 is not limited.

The central control device 100 of the air conditioning system controls the operation related to the air conditioning of each air conditioner group 1. The centralized control device 100 according to the present embodiment can increase or decrease the operating frequency of the compressor 12 included in the outdoor unit 10 of each air conditioner group 1 and instruct to stop the operation frequency. Thereby, the outdoor unit 10 (air conditioner group 1) can be stopped. Further, based on the operation information data obtained from the indoor unit 20, an instruction to change the set temperature or the like can be given. Moreover, the data in the signal sent regularly, for example from each air conditioner group 1 (outdoor unit 10) are processed, and the data of the operating frequency of the compressor 12 and a control value (the operation state in the indoor unit 20) are obtained. And based on the operating frequency etc. of the compressor 12 which the outdoor unit 10 has, the air conditioner group 1 which transmits a stop instruction | indication is determined, and the stop instruction | indication is performed with respect to the outdoor unit 10. FIG. A certain compressor 12 is stopped and the driven compressor 12 is driven at an operating frequency at or near the maximum efficiency so that air conditioning in the air-conditioned space can be performed efficiently without causing excessive effects. To save energy.

The centralized control device 100 according to the present embodiment includes a control unit 110 and a storage unit 120. The control unit 110 performs control processing based on data included in a signal from the outdoor unit control device 11 included in the outdoor unit 10 of each air conditioner group 1. The control unit 110 according to the present embodiment is configured by a microcomputer having a control processing unit such as a CPU (Central Processing Unit).

The storage unit 120 stores the data on the operating frequency of the compressor 12 and the data related to the operation state included in the signal from the outdoor unit control device 11. In particular, efficiency curve characteristics indicating the relationship between the operating frequency and efficiency of the compressor 12 are previously stored as data. For example, when different types of compressors 12 are included in the air conditioning system, data of efficiency curve characteristics of each type is included. And it has the data which made the process procedure which concerns on the control etc. which the control part 110 performs as a program. The control unit 110 implements control by executing processing based on program data.

FIG. 3 is a diagram showing a flowchart relating to the control of the air-conditioned space performed by the centralized control device 100 according to the first embodiment of the present invention. When starting the control of the air conditioning system (S1), the control unit 110 of the centralized control device 100 acquires data on the operating frequency and control value data of the compressor 12 included in the signal transmitted from each outdoor unit 10. (S2). Then, the obtained operating frequency data and control value data of each compressor 12 are stored in the storage unit 120 (S3).

And the control part 110 determines whether the outdoor unit 10 (air conditioner group 1) is stopped based on the data memorize | stored in the memory | storage part 120, and determines the outdoor unit 10 to stop. (S4). The contents of the outdoor unit stop determination process will be described later. And when there exists the outdoor unit 10 to stop (S5), the signal of a stop command is sent to the outdoor unit 10 which concerns on a stop, and stop control is performed (S6).

Further, for example, when the control unit 110 performs stop control and a certain time elapses (S7), even if the operating frequency of the compressor 12 in each outdoor unit 10 changes based on the control value data, for example, in the conditioned space. It is determined whether or not air conditioning stability is maintained (S8). If it is determined that it is not maintained, the stop control is canceled, the operation of the outdoor unit 10 is restarted, and the operating frequency of the compressor 12 of each outdoor unit 10 is returned to before the stop control (S9). The control unit 110 performs the above process once, and even if the operating frequency of the compressor 12 cannot be brought close to the operating frequency at which maximum efficiency is achieved, the control unit 110 repeatedly performs the process to maintain air conditioning stability. Meanwhile, the compressor 12 being driven is controlled so as to approach the operating frequency at which the maximum efficiency is achieved.

FIG. 4 is a flowchart showing the compressor stop determination process according to the first embodiment of the present invention. In the control described with reference to FIG. 3, the control unit 110 of the centralized control device 100 performs a compressor stop determination process for determining whether or not to stop the compressor 12. Here, a detailed procedure of the compressor stop determination process will be described.

When starting the determination process, the control unit 110 reads out the operation frequency data of the compressor 12 and the control value data of the indoor unit 20 included in the outdoor unit 10 in each air conditioner group 1 from the storage unit 120 (S11). Then, it is determined whether to stop the outdoor unit 10 (compressor 12) based on the read data and the data of the efficiency curve characteristic stored in the storage unit 120 (S12). If it is determined not to stop, the process ends.

Although it does not specifically limit about the procedure which determines whether the outdoor unit 10 is stopped, In this Embodiment, it shall judge based on the average capability value (%) set arbitrarily, for example.

For example, in the air conditioning system of the present embodiment, the air conditioner group 1a to the air conditioner group 1h perform the air conditioning of the assigned area, and perform the air conditioning of one air-conditioned space as a whole system. Therefore, the control unit 110 calculates the average capacity value (%) of the entire system.

In order to calculate the average capacity value, the control unit 110 calculates an execution capacity value for each outdoor unit 10 (air conditioner group 1) based on the following equation (1).

[Equation 1]
Effective capacity value = rated capacity value of outdoor unit 10 x capacity saving rate (1)

Then, the average ability value is calculated based on the following equation (2).

[Equation 2]
Average capacity value = (total effective capacity value / total rated capacity value of each outdoor unit 10) × 100
... (2)

When the controller 110 determines that the calculated average capacity value is higher than 40%, for example, it determines that the outdoor unit 10 (compressor 12) is not stopped. On the other hand, for example, if it is determined that it is 40% or less, it is determined that the efficiency of the entire system is low, and one of the outdoor units is determined to be stopped in order to increase the efficiency. Here, in the present embodiment, the threshold value of the average ability value is set to 40%, but the present invention is not limited to this, and an arbitrary value can be set.

If it is determined that the outdoor unit 10 is to be stopped, it is determined, based on the read data, whether or not the operation state of the indoor unit 20 or the like satisfies a stop exclusion condition provided in advance in each air conditioner group 1. (S13). Here, for example, the stop exclusion condition may be that the temperature difference indicated by the control value is greater than 3 ° C. In a state where the temperature difference between the set temperature and room temperature is large, it is necessary to continue air conditioning, and the outdoor unit 10 cannot be stopped. Further, for example, the occurrence of an abnormality in the outdoor unit 10 or the indoor unit 20 can be set as a stop exclusion condition. For the outdoor unit 10 (air conditioner group 1) determined to satisfy the condition, a process of removing it from the candidate for stop control is performed (S14).

When it is determined whether or not the stop exclusion condition is satisfied for all the air conditioner groups 1 (S15), the outdoor is stopped from the outdoor units 10 (air conditioner group 1) that are candidates for stop control. The machine 10 is determined (S16). Here, in the present embodiment, the control unit 110 determines that the outdoor unit 10 having the compressor 12 driven at the lowest operating frequency among the stop control target candidates is to be stopped. Here, in order to avoid a sudden change, it is assumed that one outdoor unit 10 is stopped, but there is no particular limitation. For example, a plurality of units may be determined and stopped.

FIG. 5 is a diagram showing the relationship between the operating frequency and efficiency of the compressor 12 during the cooling operation according to Embodiment 1 of the present invention. During cooling operation, the efficiency increases slowly from a low operating frequency and slowly decreases even at an operating frequency higher than the maximum efficiency.

FIG. 6 is a diagram showing the relationship between the operating frequency and efficiency of the compressor 12 during the heating operation according to Embodiment 1 of the present invention. During cooling operation, the maximum efficiency is obtained at an operating frequency lower than that during cooling operation.

FIG. 7 is a diagram showing the relationship between the operating frequency and efficiency of the compressor 12 included in the outdoor unit 10 before the outdoor unit stop determination process according to Embodiment 1 of the present invention. Here, the operating frequency of the compressor 12 included in the outdoor unit 10a, the outdoor unit 10b, and the outdoor unit 10c, the air conditioner group 1a (outdoor unit 10a), the air conditioner group 1b (outdoor unit 10b), and the air conditioner group. The relationship with the efficiency in 1c (outdoor unit 10c) will be described. In FIG. 7, the operating frequency of the compressor 12 which each has in order of the outdoor unit 10a, the outdoor unit 10b, and the outdoor unit 10c becomes high. However, since the air conditioning load is small, the operating frequency of the compressor 12 included in the outdoor unit 10a, the outdoor unit 10b, and the outdoor unit 10c is lower than the operating frequency at which the maximum efficiency is achieved. Among these, since the operating frequency of the compressor 12a which the outdoor unit 10a has is the lowest, the outdoor unit 10a is stopped.

FIG. 8 is a diagram showing the relationship between the operating frequency and efficiency of the compressor 12 when the compressor 12 included in one outdoor unit 10 according to Embodiment 1 of the present invention is stopped. When the outdoor unit 10a receives the stop command signal, the outdoor unit 10a stops the compressor 12. For this reason, the operating frequency of the compressor 12 of the outdoor unit 10a is zero. And the air-conditioning load which the outdoor unit 10a covered before the stop is distributed to the

outdoor units

10b and 10c, and the air conditioner group 1b and the air conditioner group 1c perform the air conditioning of the air-conditioned space. For this reason, the operating frequency of the compressor 12 in the outdoor unit 10b and the outdoor unit 10c shifts to a higher one. In the

outdoor units

10b and 10c, the operating frequency of the compressor 12 is lower than the operating frequency at which the maximum efficiency is achieved. Therefore, the

outdoor unit

10b and 10c can be operated at a high operating frequency by shifting to a higher operating frequency.

As described above, according to the air conditioning system of the first embodiment, the central control device 100 determines the outdoor unit 10 to be stopped based on the operating state of each air conditioner group 1. The compressor 12 that is driven at an operating frequency lower than the maximum-efficiency operating frequency by distributing the load can be driven at an operating frequency close to the maximum-efficiency operating frequency, so that the entire air conditioning system is efficient. You can drive.

Embodiment 2. FIG.
FIG. 9 is a diagram showing a flowchart relating to the compressor stop determination process according to the second embodiment of the present invention. In FIG. 9, the same step numbers as those in FIG. 4 are the same as those described in the first embodiment.

Although not specifically shown in the first embodiment, for example, when the compressor stop determination process is performed, the outdoor unit 10 to be stopped may be biased depending on the state of heat load and the characteristics of the air-conditioned space. For this reason, a difference may arise in the operation time of each air conditioner group 1.

As shown in FIG. 9, in the present embodiment, the control unit 110 reads data from the storage unit 120 (S11), and determines that the outdoor unit 10 (compressor 12) is stopped (S12). The process of determining whether the accumulated operation time is less than the reference operation time is performed (S13A). Then, when it is determined that the accumulated operation time is less than the reference operation time, a process of removing from the operation stop target candidates is performed (S13). If it is determined that the accumulated operation time is not less than (or more than) the reference operation time, processing is performed to determine whether the operation state of the air conditioner group 1 satisfies the stop exclusion condition (S14). As a result, the air conditioner group 1 with a short accumulated operation time is excluded from the candidates for operation stop.

As described above, according to the air conditioning system of the second embodiment, the control unit 110 determines whether the integrated operation time of the air conditioner group 1 is equal to or longer than the reference operation time, and the air with a short integrated operation time. Since the conditioner group 1 is removed from the operation stop target, it is possible to prevent the outdoor operation unit 10 of the specific air conditioner group 1 from repeatedly stopping and the occurrence of bias in the accumulated operation time. For this reason, the operating time of each air conditioner group 1 can be leveled, and the air conditioning system reliability can be improved. Moreover, the lifetime of the outdoor unit 10 can be extended.

Embodiment 3 FIG.
In the first embodiment described above, the outdoor unit 10 having the compressor 12 having the lowest operating frequency among the stop control target candidates is stopped. However, the present invention is not limited to this. For example, the outdoor unit 10 having the longest accumulated operation time among the stop control target candidates may be stopped.

1,1a-1h Air conditioner group 10,10a-10h outdoor unit 11,11a-11h outdoor unit control unit 12,12a-12h compressor, 20,20a-1-20h-2 indoor unit 21, 21a-1 to 21h-2, indoor unit control device, 100 central control device, 110 control unit, 120 storage unit.

Claims

One or a plurality of air conditioner groups having a refrigerant circuit configured by connecting an outdoor unit having a compressor capable of arbitrarily changing the operating frequency and an indoor unit that performs air conditioning of the target space;
A storage unit that stores, as data, an operating frequency of a compressor included in the outdoor unit in each air conditioner group, and a relationship between the operating frequency and energy efficiency of the compressor included in the outdoor unit of each air conditioner group, and the storage unit Control for performing outdoor unit stop determination processing for determining an outdoor unit to be stopped based on the stored data so that the compressor of the outdoor unit of the operating air conditioner group approaches the operating frequency at which maximum efficiency is achieved. An air conditioning system comprising a central control device having a section.
2. The air conditioning system according to claim 1, wherein the control unit performs a process of determining the air conditioner group that is a target of the outdoor unit stop process based on a condition relating to an operation state of each of the air conditioner groups. .
The air conditioning system according to claim 1 or 2, wherein the control unit performs a process of excluding the air conditioner group whose accumulated operation time is less than a reference operation time from the air conditioner group that is a target of an outdoor unit stop process. .