Air conditioning system

Abstract

This air conditioning system (10) comprises an air conditioner (2) for performing air conditioning, and a management device (1) for managing the operating state of the air conditioner (2), wherein the management device (1) is provided with: an operation data acquisition unit (6) for acquiring operation data from the air conditioner (2); an operation data storage unit (4) for storing the acquired past operation data; a refrigerant leakage assessment unit (7) for assessing whether refrigerant has leaked on the basis of the operation data; a refrigerant leakage assessability operation data assessment unit (5) that assesses whether the past operation data can be used in assessing refrigerant leakage; and an operation control unit (3) that, when the past operation data cannot be used in assessing refrigerant leakage and the operation load of the air conditioner (2) calculated from current operation data is greater than or equal to a preset high-load operation implementation, performs a high-load operation implementation process for operating the air conditioner (2) at a higher load than the operation load calculated from the current operation data.

Description

Air conditioning system

[0001] The present disclosure relates to an air conditioning system including an air conditioner that performs air conditioning by a refrigeration cycle using a refrigerant.

[0002] Conventionally, in an air conditioning system including an air conditioner that performs air conditioning by a refrigeration cycle using a refrigerant, a method of determining refrigerant leakage based on operation data indicating the operation state of the air conditioner is known. When determining refrigerant leakage based on the operation data of the air conditioner, operation data in a state where the operation load of the air conditioner is relatively high is required.

[0003] Patent Document 1 discloses an air conditioning system capable of obtaining operation data in a high operation load state required for determining refrigerant leakage by automatically performing a high load operation on the air conditioner even when the compressor that compresses and sends out the refrigerant in the refrigeration cycle is stopped.

[0004] Japanese Patent Application Laid-Open No. 2022-179199

[0005] However, the air conditioning system disclosed in Patent Document 1 automatically performs a high load operation on the air conditioner even in a situation where there is no user and the compressor has stopped operating, resulting in problems such as an increase in power consumption and wear of the air conditioner.

[0006] The present disclosure has been made in view of the above, and an object thereof is to obtain an air conditioning system capable of determining refrigerant leakage while suppressing wear of the air conditioner that performs air conditioning by a refrigeration cycle using a refrigerant and an increase in power consumption.

[0007] To solve the above-mentioned problems and achieve the objective, the air conditioning system according to this disclosure is an air conditioning system comprising an air conditioner that performs air conditioning by a refrigeration cycle using a refrigerant, and a management device that manages the operating state of the air conditioner, wherein the management device comprises an operating data acquisition unit that acquires operating data from the air conditioner, and an operating data storage unit that stores the acquired past operating data. The management device comprises a refrigerant leak determination unit that determines whether or not refrigerant has leaked based on the operating data, a refrigerant leak determination-capable operating data determination unit that determines whether or not past operating data is data that can be used to determine refrigerant leak, and an operation control unit that performs a high-load operation execution process to operate the air conditioner at a higher load than the operating load of the air conditioner calculated from the current operating data if the past operating data is not data that can be used to determine refrigerant leak, and the operating load of the air conditioner calculated from the current operating data acquired by the operating data acquisition unit is equal to or greater than a preset high-load operation execution threshold.

[0008] The air conditioning system described herein has the effect of being able to detect refrigerant leakage while suppressing wear and tear on air conditioners that perform air conditioning using a refrigeration cycle with a refrigerant, and preventing an increase in power consumption.

[0009] A figure showing the configuration of an air conditioning system using an air conditioner according to Embodiment 1. A figure showing the configuration of the air conditioning system management device and air conditioner according to Embodiment 1. A flowchart showing the operation flow of the air conditioning system management device according to Embodiment 1. A figure showing an example of the operating load behavior of the air conditioner in the air conditioning system according to Embodiment 1. A figure showing the configuration of the air conditioning system management device and air conditioner according to Embodiment 2. A flowchart showing the operation flow of the air conditioning system management device according to Embodiment 2. A figure showing an example of the hardware configuration that realizes the air conditioning system management device according to Embodiment 1 or Embodiment 2.

[0010] The air conditioning system according to the embodiment will be described in detail below with reference to the drawings.

[0011] Embodiment 1. Figure 1 shows the configuration of an air conditioning system using an air conditioner according to Embodiment 1. The air conditioning system 10 comprises an air conditioner 2 that performs air conditioning and a management device 1 that manages the operating state of the air conditioner 2. The management device 1 is, for example, a server.

[0012] Figure 2 shows the configuration of the control device and air conditioner of the air conditioning system according to Embodiment 1. The air conditioner 2 includes a refrigeration cycle 21 that performs air conditioning using a refrigerant. The refrigeration cycle 21 has a general configuration that includes a compressor 22 that compresses and sends out the refrigerant.

[0013] The control device 1 includes an operation data acquisition unit 6 that acquires operation data of the air conditioner 2, an operation data storage unit 4 that stores the acquired operation data, a refrigerant leak determination unit 7 that determines whether or not refrigerant has leaked based on the operation data stored in the operation data storage unit 4, a refrigerant leak determination capable operation data determination unit 5 that determines whether or not the operation data stored in the operation data storage unit 4 can be used to determine whether or not refrigerant has leaked, and an operation control unit 3 that causes the air conditioner 2 to perform high-load operation when it is not possible to determine whether or not refrigerant has leaked using past operation data.

[0014] The operation of the air conditioning system 10 will now be described. In the example described below, the operating load of the air conditioner 2 is assumed to be the rotation rate of the compressor 22 that compresses and sends out the refrigerant in the refrigeration cycle 21. Furthermore, the control device 1 is assumed to have a refrigerant leakage detection threshold and a high-load operation threshold stored in advance. The high-load operation threshold is a threshold set in advance as a criterion for deciding whether or not to perform high-load operation, which increases the operating load in order to enable the detection of refrigerant leakage. The refrigerant leakage detection threshold is a threshold that indicates the operating load of the air conditioner 2 that outputs operating data that makes it possible to detect refrigerant leakage. By determining refrigerant leakage based on the operating data of the air conditioner 2 where the operating load is equal to or greater than the refrigerant leakage detection threshold, the refrigerant leakage detection unit 7 can determine refrigerant leakage.

[0015] For example, the threshold for detecting refrigerant leakage is set to 90% of the maximum rotational speed of the compressor 22. Furthermore, the threshold for performing high-load operation is set to a value lower than the threshold for detecting refrigerant leakage. For example, the threshold for performing high-load operation is set to 80% of the maximum rotational speed of the compressor 22.

[0016] Figure 3 is a flowchart showing the operation flow of the control device for the air conditioning system according to Embodiment 1. The operation shown in Figure 3 is an operation to perform a high-load operation execution process, which operates the air conditioner 2 at a higher load than the operating load calculated from the current operating data, when the past operating data is not data that can be used to determine refrigerant leakage, and the operating load of the air conditioner 2 calculated from the current operating data acquired by the operating data acquisition unit 6 is equal to or greater than a preset high-load operation execution threshold. The operation shown in Figure 3 is executed when the current time falls within a preset time period or a time period determined based on past operating data. The control device 1 starts processing when the preset high-load operation execution time arrives. The high-load operation execution time is set to a time period with a high air conditioning load, such as during the daytime in summer and in the morning in winter. In step S1, the refrigerant leakage determination unit 5 acquires past operating data stored in the operating data storage unit 4. Past operating data refers to, for example, operating data from the date and time when the refrigerant leakage was last determined to the current high-load operation execution time. In step S2, the refrigerant leak detection operation data determination unit 5 calculates the past operating load of the air conditioner 2 based on past operating data. In this example, the refrigerant leak detection operation data determination unit 5 calculates the past rotation rate of the compressor 22.

[0017] In step S3, the refrigerant leak detection capable operation data determination unit 5 determines whether the maximum past operating load of the air conditioner 2 is less than the refrigerant leak detection threshold. In this example, the refrigerant leak detection capable operation data determination unit 5 determines whether the calculated maximum past rotation rate of the compressor 22 is less than the refrigerant leak detection threshold. If the calculated maximum past operating load of the air conditioner 2 is greater than or equal to the refrigerant leak detection threshold, the result in step S3 is No. In this example, if the calculated maximum past rotation rate of the compressor 22 is greater than or equal to the refrigerant leak detection threshold, the result in step S3 is No. In this case, since refrigerant leakage can be determined using the maximum past rotation rate of the compressor 22, the refrigerant leak detection capable operation data determination unit 5 proceeds to step S8. If the calculated maximum past operating load of the air conditioner 2 is less than the refrigerant leak detection threshold, the result in step S3 is Yes, and the process proceeds to step S4. In the example shown here, if the calculated maximum past rotational speed of the compressor 22 is less than the threshold for determining refrigerant leakage, the answer in step S3 is Yes. If the answer in step S3 is Yes, it means that the past operating data has been determined to be unusable for determining refrigerant leakage.

[0018] In step S4, the refrigerant leak detection capable operation data determination unit 5 acquires the current operation data from the operation data acquisition unit 6. In step S5, the refrigerant leak detection capable operation data determination unit 5 calculates the current operating load of the air conditioner 2 based on the current operation data. In this example, the refrigerant leak detection capable operation data determination unit 5 calculates the current rotation rate of the compressor 22.

[0019] In step S6, the refrigerant leak detection-enabled operation data determination unit 5 determines whether the calculated current operating load of the air conditioner 2 is equal to or greater than the high-load operation threshold. In this example, the refrigerant leak detection-enabled operation data determination unit 5 determines whether the calculated current rotation rate of the compressor 22 is equal to or greater than the high-load operation threshold. If the calculated current operating load of the air conditioner 2 is less than the high-load operation threshold, the result in step S6 is No, and the process ends. In this example, if the calculated current rotation rate of the compressor 22 is less than the high-load operation threshold, the result in step S6 is No. If the calculated current operating load of the air conditioner 2 is equal to or greater than the high-load operation threshold, the result in step S6 is Yes, and the process proceeds to step S7. In this example, if the calculated current rotation rate of the compressor 22 is equal to or greater than the high-load operation threshold, the result in step S6 is Yes. Note that if the result in step S6 is Yes, it means that the operating load of the air conditioner 2 calculated from the current operating data acquired by the operation data acquisition unit 6 has been determined to be equal to or greater than the preset high-load operation threshold.

[0020] In step S7, the operation control unit 3 causes the air conditioner 2 to perform high-load operation until an operating load equal to or greater than the refrigerant leakage detection threshold is obtained. In this example, the operation control unit 3 causes the air conditioner 2 to perform high-load operation until a compressor 22 rotation rate equal to or greater than the refrigerant leakage detection threshold is obtained. In step S8, the refrigerant leakage detection unit 7 uses past operating data or operating data acquired during high-load operation to determine whether or not refrigerant has leaked. That is, if the result in step S3 is No, the refrigerant leakage detection unit 7 uses past operating data to determine whether or not refrigerant has leaked. If the result in both step S3 and step S6 is Yes, the refrigerant leakage detection unit 7 uses operating data acquired during high-load operation to determine whether or not refrigerant has leaked.

[0021] Through the above operations, the operation control unit 3 can perform high-load operation processing if the current time falls within a preset time period or a time period determined based on past operation data.

[0022] Figure 4 shows an example of the operating load behavior of the air conditioner in the air conditioning system according to Embodiment 1. In Figure 4, the solid line shows the operating load behavior of the air conditioner 2 in the air conditioning system 10 according to Embodiment 1, and the dashed line shows the operating load behavior of the air conditioner in the comparative example air conditioning system in which the air conditioner does not perform high-load operation. In the comparative example air conditioning system, the maximum value of the operating load of the air conditioner is less than the threshold for detecting refrigerant leakage. Therefore, it is not possible to detect refrigerant leakage in the comparative example air conditioning system. On the other hand, in the air conditioning system 10 according to Embodiment 1, the operating load of the air conditioner 2 at the time of high-load operation is greater than or equal to the high-load operation threshold and less than the threshold for detecting refrigerant leakage, so high-load operation is started at the time of high-load operation. As a result, in the air conditioning system 10 according to Embodiment 1, the operating load of the air conditioner 2 becomes higher than the operating load of the air conditioner in the comparative example air conditioning system, and the maximum value of the operating load of the air conditioner 2 exceeds the threshold for detecting refrigerant leakage. Therefore, it is possible to detect refrigerant leakage in the air conditioning system 10 according to Embodiment 1.

[0023] As described above, the air conditioning system 10 according to Embodiment 1 causes the air conditioner 2 to perform high-load operation when it is operating at an operating load exceeding a preset high-load operation threshold. As a result, the air conditioning system 10 according to Embodiment 1 can reduce power consumption and suppress wear on the air conditioner 2 while detecting refrigerant leakage, compared to when high-load operation is performed from a stopped state. Furthermore, since the air conditioner 2 operates under operating conditions different from the user settings during high-load operation, causing the air conditioner 2 to perform high-load operation can impair user comfort. The air conditioning system 10 according to Embodiment 1 does not cause the air conditioner 2 to perform high-load operation when the current operating load of the air conditioner 2 is below the high-load operation threshold, so the air conditioner 2 is not operated under operating conditions far removed from the user settings, and user comfort is less likely to be impaired.

[0024] Embodiment 2. Figure 5 shows the configuration of the control device and air conditioner of the air conditioning system according to Embodiment 2. The air conditioning system 10 according to Embodiment 2 differs from the air conditioning system 10 according to Embodiment 1 in that the air conditioner 2 is equipped with a human presence sensor 8 that detects people around it. The output of the human presence sensor 8 is acquired by the operation data acquisition unit 6 as part of the operation data.

[0025] The operation of the air conditioning system 10 according to Embodiment 2 will now be described. Figure 6 is a flowchart showing the operation flow of the control device for the air conditioning system according to Embodiment 2. The processing from step S1 to step S5 is the same as that of the air conditioning system 10 according to Embodiment 1. In the air conditioning system 10 according to Embodiment 2, in step S5, the current operating load, in this example, the current rotation rate of the compressor 22, is calculated, and then the process proceeds to step S9. In step S9, the refrigerant leakage detection operation data determination unit 5 determines whether or not there are people around the air conditioner 2 based on the data obtained by the human presence sensor 8. If there are people, the result in step S9 is Yes, and the process proceeds to step S6, where the refrigerant leakage detection operation data determination unit 5 makes a determination to perform high-load operation without changing the high-load operation threshold.

[0026] On the other hand, if there are no people around the air conditioner 2, the result in step S9 is No, and the process proceeds to step S10. In step S10, the refrigerant leak detection capable operation data determination unit 5 lowers the high-load operation threshold. For example, if the original high-load operation threshold is 80% of the maximum rotational speed of the compressor 22, the refrigerant leak detection capable operation data determination unit 5 lowers the high-load operation threshold to 60% of the maximum rotational speed of the compressor 22. After that, the process proceeds to step S6, where the refrigerant leak detection capable operation data determination unit 5 makes a determination on whether high-load operation is to be performed. The process from step S6 onward is the same as that of the air conditioning system 10 according to Embodiment 1.

[0027] As described above, the air conditioning system 10 according to Embodiment 2, like the air conditioning system 10 according to Embodiment 1, can reduce power consumption and suppress wear on the air conditioner 2 while determining refrigerant leakage, compared to the case where the air conditioner 2 is made to perform high-load operation from a state where it is stopped. Furthermore, the air conditioning system 10 according to Embodiment 2 detects people using the human presence sensor 8 and lowers the high-load operation threshold for the air conditioner 2 when there are no people around it. Therefore, when there are no people around the air conditioner 2, high-load operation of the air conditioner 2 is more likely to be performed compared to the air conditioning system 10 according to Embodiment 1. As a result, when there are no people around the air conditioner 2, the operating load of the air conditioner 2 is more likely to exceed the refrigerant leakage detection threshold in the air conditioning system 10 according to Embodiment 2, making it easier to determine refrigerant leakage. In addition, the air conditioning system 10 according to Embodiment 2 does not lower the high-load operation threshold when there are people around the air conditioner 2, so the air conditioner 2 is not operated under operating conditions far removed from the user settings when there are people around the air conditioner 2, and user comfort is less likely to be compromised.

[0028] Next, the hardware configuration of the control device 1 of the air conditioning system 10 according to Embodiment 1 or Embodiment 2 will be described. Figure 7 is a diagram showing an example of the hardware configuration for realizing the control device of the air conditioning system according to Embodiment 1 or Embodiment 2. The control device 1 is realized as a computer system by a processing circuit that includes a processor 91 that performs various processes, a memory 92 which is the main memory, and a storage device 93 that stores information.

[0029] The processor 91 may be a computing means such as an arithmetic unit, microprocessor, microcomputer, CPU (Central Processing Unit), or DSP (Digital Signal Processor). The memory 92 may be a non-volatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), or EEPROM® (Electrically Erasable Programmable Read Only Memory). The storage device 93 stores a program for executing the following: a process to determine whether or not refrigerant has leaked based on the operating data; a process to determine whether or not past operating data can be used to determine refrigerant leakage; and, if past operating data cannot be used to determine refrigerant leakage, and the operating load of the air conditioner 2 calculated from the current operating data acquired by the operating data acquisition unit 6 is equal to or greater than a preset high-load operation threshold, the program to operate the air conditioner 2 at a higher load than the operating load of the air conditioner 2 calculated from the current operating data. The processor 91 reads the program stored in the storage device 93 into the memory 92 and executes it. The functions of the management device 1 are realized when the processor 91 reads the program stored in the storage device 93 into the memory 92 and executes it.

[0030] The configurations shown in the above embodiments are merely examples of the content, and can be combined with other known technologies. It is also possible to omit or modify parts of the configuration without departing from the gist of the invention.

[0031] 1 Control device, 2 Air conditioner, 3 Operation control unit, 4 Operation data storage unit, 5 Refrigerant leak detection operation data determination unit, 6 Operation data acquisition unit, 7 Refrigerant leak detection unit, 8 Human presence sensor, 10 Air conditioning system, 21 Refrigeration cycle, 22 Compressor, 91 Processor, 92 Memory, 93 Storage device.

Claims

1. An air conditioning system comprising an air conditioner that performs air conditioning by a refrigeration cycle using a refrigerant, and a management device that manages the operating state of the air conditioner, wherein the management device comprises: an operating data acquisition unit that acquires operating data from the air conditioner; an operating data storage unit that stores the acquired past operating data; a refrigerant leak determination unit that determines whether or not the refrigerant has leaked based on the operating data; a refrigerant leak determination-capable operating data determination unit that determines whether or not the past operating data is data that can be used to determine the refrigerant leak; and an operation control unit that performs a high-load operation execution process to operate the air conditioner at a higher load than the operating load of the air conditioner calculated from the current operating data when the past operating data is not data that can be used to determine the refrigerant leak, and the operating load of the air conditioner calculated from the current operating data acquired by the operating data acquisition unit is equal to or greater than a preset high-load operation execution threshold.

2. The air conditioning system according to claim 1, wherein the refrigerant leak determination unit determines whether or not the refrigerant has leaked based on the operating data obtained from the air conditioner while it is operating at a load higher than the operating load of the air conditioner calculated from the current operating data, when the operation control unit operates the air conditioner at a load higher than the operating load of the air conditioner calculated from the current operating data.

3. The air conditioning system according to claim 1 or 2, wherein the operation control unit performs the high-load operation execution process when the current time falls within a preset time period or a time period determined based on past operation data.

4. An air conditioning system according to any one of claims 1 to 3, comprising a motion sensor for detecting people around the air conditioner, wherein the refrigerant leakage determination unit lowers the high-load operation threshold if no people are detected by the motion sensor.

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