JP2018141607A - Refrigerant amount determination device, air conditioning system, refrigerant amount determination method and program - Google Patents

Abstract

To determine with high accuracy whether or not the amount of refrigerant in an air conditioning system is appropriate.
An expansion valve opening information indicating an opening of a determination target expansion valve, wherein the refrigerant amount determination device is at least one of an expansion valve of an indoor unit provided in an air conditioning system or an expansion valve on a supercooling heat exchanger side. An information acquisition unit that acquires the degree of supercooling of an outdoor heat exchanger included in the air conditioning system, and an opening degree of the determination target expansion valve before the degree of supercooling is increased A refrigerant amount determination unit that determines whether or not the refrigerant amount of the air-conditioning system is appropriate based on the opening degree of the determination target expansion valve after increasing the degree of supercooling.
[Selection] Figure 3

Description

  The present invention relates to a refrigerant amount determination device, an air conditioning system, a refrigerant amount determination method, and a program.

  In order to operate the air conditioning system efficiently, it is important that an appropriate amount of refrigerant is sealed in the air conditioning system. In relation to this, Patent Document 1 discloses a refrigerant filling amount determination method. In the refrigerant filling amount determination method described in Patent Document 1, when the air conditioning system is operated in a cooling cycle, and the opening degree of one or both of the indoor expansion valve and the subcooling expansion valve is equal to or greater than a predetermined value. Further, it is determined that the refrigerant charging amount is in the gas low state.

JP 2008-96051 A

According to the refrigerant filling amount determination method described in Patent Literature 1, it is possible to detect the gas low state of the air conditioning system. When the gas low state of the air conditioning system is detected, the air conditioning system can be efficiently operated by increasing the amount of refrigerant in the air conditioning system.
It is further preferable if it can be determined with higher accuracy whether or not the refrigerant amount of the air conditioning system is appropriate.

  The present invention provides a refrigerant amount determination device, an air conditioning system, a refrigerant amount determination method, and a program capable of determining with high accuracy whether or not the refrigerant amount of an air conditioning system is appropriate.

  According to the first aspect of the present invention, the refrigerant amount determination device is an opening degree of the determination target expansion valve that is at least one of the expansion valve of the indoor unit and the expansion valve on the supercooling heat exchanger side provided in the air conditioning system. An information acquisition unit that acquires expansion valve opening information indicating the degree of supercooling, an overcooling degree adjustment unit that increases the degree of subcooling of the outdoor heat exchanger included in the air conditioning system, and the determination before increasing the degree of supercooling A refrigerant amount determination unit that determines whether or not the refrigerant amount of the air conditioning system is appropriate based on the opening of the target expansion valve and the opening of the determination target expansion valve after increasing the degree of supercooling And comprising.

  The supercooling degree adjusting unit may increase the supercooling degree by reducing an opening degree of an expansion valve on an outdoor heat exchanger side included in the air conditioning system.

  The refrigerant amount determination unit further determines whether or not the refrigerant amount of the air conditioning system is appropriate based on the subcooling degree before the supercooling degree adjustment unit increases the supercooling degree. Also good.

  The supercooling degree adjustment unit sets the supercooling degree to a first supercooling degree, a second supercooling degree larger than the first supercooling degree, and a third supercooling degree larger than the second supercooling degree. The refrigerant amount determination unit is configured to change the air conditioning based on the opening degree of the determination target expansion valve in each of the first subcooling degree, the second subcooling degree, and the third subcooling degree. You may make it determine whether the refrigerant | coolant amount of a system is appropriate.

  According to the 2nd aspect of this invention, an air conditioning system is provided with the refrigerant | coolant amount determination apparatus as described in any one of the above-mentioned.

  According to the 3rd aspect of this invention, the refrigerant | coolant amount determination method increases the subcooling degree of the outdoor heat exchanger with which an air conditioning system is provided, The room with which the said air conditioning system is before increasing a supercooling degree is provided. Based on the opening degree of the determination target expansion valve that is at least one of the expansion valve of the compressor or the expansion valve on the supercooling heat exchanger side and the opening degree of the determination target expansion valve after increasing the degree of supercooling And determining whether or not the amount of refrigerant in the air conditioning system is appropriate.

  According to the fourth aspect of the present invention, the program causes the computer that controls the air conditioning system to perform control for increasing the degree of supercooling of the outdoor heat exchanger included in the air conditioning system, thereby increasing the degree of supercooling. Before opening, the opening degree of the determination target expansion valve that is at least one of the expansion valve of the indoor unit provided in the air conditioning system or the expansion valve on the supercooling heat exchanger side, and the degree after the supercooling degree is increased This is a program for determining whether or not the amount of refrigerant in the air conditioning system is appropriate based on the opening degree of the determination target expansion valve.

  According to the refrigerant amount determination device, the air conditioning system, the refrigerant amount determination method, and the program described above, it can be determined with higher accuracy whether or not the refrigerant amount of the air conditioning system is appropriate.

It is a schematic block diagram which shows the function structure of the air conditioning system which concerns on embodiment of this invention. It is a schematic block diagram which shows the example of the apparatus structure of the air conditioning system main body which concerns on the same embodiment. It is a schematic block diagram which shows the function structure of the control apparatus which concerns on the same embodiment. It is a figure which shows the example of the determination reference | standard when the refrigerant | coolant amount determination part which concerns on the same embodiment determines whether the refrigerant | coolant amount is appropriate based on the data in two steps of supercooling degrees. It is a flowchart which shows the example of the process sequence in case the control apparatus which concerns on the same embodiment determines whether the refrigerant | coolant amount is appropriate based on the data in two steps of supercooling degrees. It is a flowchart which shows the example of the process sequence which the control apparatus which concerns on the same embodiment increases the subcooling degree of an outdoor heat exchanger. It is a figure which shows the example of the determination reference | standard when the refrigerant | coolant amount determination part which concerns on the same embodiment determines whether the refrigerant | coolant amount is appropriate based on the data in three steps of supercooling degrees. It is a flowchart which shows the example of the process sequence in case the control apparatus which concerns on the same embodiment determines whether the refrigerant | coolant amount is appropriate based on the data in three steps of supercooling degrees.

Hereinafter, although embodiment of this invention is described, the following embodiment does not limit the invention concerning a claim. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.
FIG. 1 is a schematic block diagram showing a functional configuration of an air conditioning system according to an embodiment of the present invention. As shown in FIG. 1, the air conditioning system 1 includes an air conditioning system main body 100 and a control device 400.

The air conditioning system main body 100 operates according to the control of the control device 400 and adjusts the indoor air temperature that is a temperature adjustment target. However, the object on which the air conditioning system main body 100 performs temperature adjustment is not limited to the room. For example, the air conditioning system main body 100, such as outdoor spot air conditioning, may adjust the air temperature in the outdoor space.
FIG. 2 is a schematic configuration diagram illustrating an example of a device configuration of the air conditioning system main body 100. In the example of FIG. 2, the air conditioning system main body 100 includes an outdoor unit 200 and an indoor unit 300. The outdoor unit 200 includes a compressor 211, an accumulator 212, a four-way valve 221, an outdoor heat exchanger 231, an outdoor expansion valve 232, a receiver tank 241, a supercooling heat exchanger 251, and a supercooling side expansion. A valve 252, a high pressure side pressure sensor 291, and an outdoor heat exchanger outlet temperature sensor 292 are provided. The indoor unit 300 includes an indoor heat exchanger 311 and an indoor unit side expansion valve 312.

Although FIG. 2 shows an example where the air conditioning system main body 100 includes a plurality of indoor units 300, the number of indoor units 300 included in the air conditioning system main body 100 may be one or more. The number of outdoor units 200 included in the air conditioning system main body 100 may be one or more.
Further, the installation location of the compressor 211, the accumulator 212, the four-way valve 221, the receiver tank 241, the supercooling heat exchanger 251, and the supercooling side expansion valve 252 is not limited to the outdoor unit 200. For example, some or all of the compressor 211, the accumulator 212, the four-way valve 221, the receiver tank 241, the supercooling heat exchanger 251, and the supercooling side expansion valve 252 are configured as a device separate from the outdoor unit 200. For example, it may be installed outside the outdoor unit 200.
The air conditioning system 1 may be a system dedicated to cooling. In the example of FIG. 2, switching between the cooling cycle and the heating cycle is performed by switching the four-way valve 221.

  In the cooling cycle, the gaseous refrigerant compressed by the compressor 211 flows into the outdoor heat exchanger 231 via the four-way valve 221. The gaseous refrigerant that has flowed into the outdoor heat exchanger 231 dissipates heat and condenses through heat exchange with outdoor air. The refrigerant that has become liquid by condensation flows into the receiver tank 241 via the outdoor expansion valve 232. The receiver tank 241 stores a sufficient amount of refrigerant for coping with changes in operating conditions.

  The refrigerant flowing out from the receiver tank 241 is supercooled by the supercooling heat exchanger 251 and then flows into the indoor unit 300. The supercooling heat exchanger 251 performs supercooling of the refrigerant in order to prevent the refrigerant from evaporating in the pipe between the outdoor unit 200 and the indoor unit 300. Specifically, a part of the liquid refrigerant flowing out of the receiver tank 241 is decompressed by the supercooling side expansion valve 252, then flows into the supercooling heat exchanger 251, and evaporates in the supercooling heat exchanger 251. This evaporating refrigerant exchanges heat with the refrigerant flowing into the indoor unit 300 from the receiver tank 241 via the supercooling heat exchanger 251 and takes heat of evaporation. Thereby, the refrigerant flowing into the indoor unit 300 from the receiver tank 241 via the supercooling heat exchanger 251 is supercooled.

The refrigerant flowing into the supercooling heat exchanger 251 from the receiver tank 241 via the supercooling side expansion valve 252 evaporates in the supercooling heat exchanger 251 to become a gas, and then passes through the accumulator 212 to become a compressor. It flows into 211 and is compressed.
However, the supercooling heat exchanger 251 and the supercooling side expansion valve 252 are not essential to the air conditioning system main body 100. For example, when it is not necessary to worry about the evaporation of the refrigerant, such as when the distance between the pipes between the outdoor unit 200 and the indoor unit 300 is short, the air conditioning system main body 100 includes the supercooling heat exchanger 251 and the supercooling side expansion valve. 252 may not be provided.

The refrigerant flowing into the indoor unit 300 is decompressed by the indoor unit side expansion valve 312 and then flows into the indoor heat exchanger 311.
The refrigerant flowing into the indoor heat exchanger 311 absorbs heat and evaporates by heat exchange with the indoor air. The indoor air is cooled by this heat absorption.
The refrigerant turned into gas by evaporation flows into the compressor 211 via the four-way valve 221 and the accumulator 212 and is compressed. The accumulator 212 separates the refrigerant flowing into the accumulator 212 itself into a liquid refrigerant and a gaseous refrigerant, and allows only the gaseous refrigerant to flow into the compressor 211. This is to prevent the refrigerant 211 from flowing into the compressor 211 and the compressor 211 from being reduced in capacity or malfunctioning.

The high pressure side pressure sensor 291 is provided in a pipe between the four-way valve 221 and the outdoor heat exchanger 231 and measures the refrigerant pressure in the pipe. Particularly in the case of the cooling cycle, the high pressure side pressure sensor 291 measures the pressure of the refrigerant of high pressure gas that is compressed by the compressor 211 and flows into the outdoor heat exchanger 231 via the four-way valve 221. In this case, the information acquisition unit 491 calculates the pressure saturation temperature of the outdoor heat exchanger 231 based on the pressure measured by the high-pressure sensor 291.
The outdoor heat exchanger outlet temperature sensor 292 is provided at the outlet of the outdoor heat exchanger 231 and measures the temperature of the refrigerant flowing out of the outdoor heat exchanger 231.

  The control device 400 controls the air conditioning system main body 100 to adjust the room temperature. The control device 400 corresponds to an example of the refrigerant amount determination device, and determines whether or not the refrigerant amount of the air conditioning system 1 (the refrigerant amount of the air conditioning system main body 100) is appropriate. The amount of refrigerant in the air conditioning system 1 is the amount of refrigerant sealed in the air conditioning system 1. The refrigerant amount of the air conditioning system 1 is also referred to as the refrigerant amount of the air conditioning system main body 100.

The control device 400 is configured using a computer such as a microcomputer (Micro Computer), for example.
The installation position of the control device 400 is not limited to a specific position. For example, the control device 400 may be installed inside the outdoor unit 200, may be installed inside the indoor unit 300, or is configured as a separate device from the outdoor unit 200 and the indoor unit 300. Also good.
Further, the refrigerant amount determination device may be configured as a device different from the control device 400.

  FIG. 3 is a schematic block diagram illustrating a functional configuration of the control device 400. As illustrated in FIG. 3, the control device 400 includes a communication unit 410, an operation input unit 420, a display unit 430, a storage unit 480, and a control unit 490. The control unit 490 includes an information acquisition unit 491, a supercooling degree adjustment unit 492, and a refrigerant amount determination unit 493.

The communication unit 410 communicates with other devices. In particular, the communication unit 410 receives a sensor signal indicating a pressure measurement value by the high-pressure sensor 291 and a sensor signal indicating a temperature measurement value by the outdoor heat exchanger outlet temperature sensor 292. Moreover, the communication part 410 transmits the control signal with respect to each part of the air conditioning system main body 100. FIG.
The operation input unit 420 includes an input device such as a push button and receives a user operation. All or part of the operation input unit 420 may be arranged in a remote controller.

The display unit 430 includes a display device such as a liquid crystal panel, a lamp, or a combination thereof, and displays various types of information. In particular, the display unit 430 displays a determination result as to whether or not the refrigerant amount is appropriate. For example, the display unit 430 includes an excessive refrigerant amount alarm lamp that indicates an excessive refrigerant amount and an excessive refrigerant amount lamp that indicates an excessive refrigerant amount. When the refrigerant amount determination unit 493 determines that the refrigerant amount is excessive, the display unit 430 turns on the excessive refrigerant amount alarm lamp. In addition, when the refrigerant amount determination unit 493 determines that the refrigerant amount is too low, the display unit 430 turns on the refrigerant amount under alarm lamp.
All or part of the display unit 430 may be arranged on the remote controller.

The storage unit 480 stores various types of information. The storage unit 480 is configured using a storage device provided in the control device 400.
The control unit 490 controls each unit of the control device 400 and executes various processes. The control unit 490 is configured by, for example, a CPU (Central Processing Unit) included in the control device 400 reading out a program from the storage unit 480 and executing it.

The information acquisition unit 491 acquires expansion valve opening information indicating the opening of the determination target expansion valve. The determination target expansion valve here is one or both of the subcooling side expansion valve 252 and the indoor unit side expansion valve 312. The supercooling side expansion valve 252 corresponds to an expansion valve on the supercooling heat exchanger 251 side. The indoor unit side expansion valve 312 corresponds to the expansion valve of the indoor unit 300. When the air conditioning system main body 100 includes a plurality of indoor units 300 and the indoor unit side expansion valves 312 are used as the determination target expansion valves, the indoor unit side expansion valves 312 of all the indoor units 300 are used as the determination target expansion valves. The indoor unit side expansion valves 312 of some of the indoor units 300 may be used as the determination target expansion valve.
The information acquisition unit 491 may acquire the opening command value of the determination target expansion valve as the expansion valve opening information. Or you may make it the information acquisition part 491 acquire the opening degree measured value of a determination object expansion valve as expansion valve opening degree information.

The supercooling degree adjustment unit 492 increases the supercooling degree of the outdoor heat exchanger 231. The degree of supercooling of the outdoor heat exchanger 231 here is indicated by a temperature difference between the outlet temperature of the outdoor heat exchanger 231 and the pressure saturation temperature of the outdoor heat exchanger 231. It is considered that the larger the outdoor heat exchanger 231 is, the more liquid refrigerant is accumulated in the outdoor heat exchanger 231.
The supercooling degree adjusting unit 492 increases the supercooling degree by reducing the opening degree of the outdoor expansion valve 232. Alternatively, the outdoor unit 200 may include a flow rate adjustment valve for adjusting the degree of supercooling separately from the outdoor expansion valve 232, and the degree of supercooling degree adjustment unit 492 may control the opening degree of the flow rate adjustment valve.

The refrigerant amount determination unit 493 determines whether or not the refrigerant amount of the air conditioning system 1 is appropriate. Specifically, the refrigerant amount determination unit 493 adjusts the degree of opening of the determination target expansion valve and the degree of subcooling of the outdoor heat exchanger 231 before the subcooling degree adjustment unit 492 increases the degree of subcooling, and the degree of subcooling. The determination is performed based on the opening degree of the determination target expansion valve after the portion 492 increases the degree of supercooling. Alternatively, the supercooling degree adjustment unit 492 does not use the information on the degree of supercooling of the outdoor heat exchanger 231, and the opening degree and the supercooling of the determination target expansion valve before the supercooling degree adjustment unit 492 increases the supercooling degree. The determination may be made based on the opening degree of the determination target expansion valve after the degree is increased.
When a plurality of expansion valves are included in the determination target expansion valve, the refrigerant amount determination unit 493 may perform determination using the average value of the opening degrees of the plurality of valves, or may use the mode value. You may make it perform determination. Or you may make it the refrigerant | coolant amount determination part 493 perform determination based on the majority vote whether the opening degree of each of these some valves has exceeded the threshold value.

  FIG. 4 is a diagram illustrating an example of a determination criterion when the refrigerant amount determination unit 493 determines whether or not the refrigerant amount is appropriate based on data at two stages of supercooling degrees. In the example of FIG. 4, the refrigerant amount determination unit 493 determines whether the refrigerant amount enclosed in the air conditioning system main body 100 is appropriate, excessive, or insufficient based on the abnormality determination results in the normal state and after the degree of supercooling increases. It is determined whether it is.

For example, the storage unit 480 stores determination criterion information indicating the determination criterion in advance. And the refrigerant | coolant amount determination part 493 performs determination using this determination reference | standard information.
The normal state here is a state before the supercooling degree adjusting unit 492 increases the supercooling degree of the outdoor heat exchanger 231. Therefore, the normal state here is a state in which control for restricting the outdoor expansion valve 232 is not performed in order to increase the degree of supercooling of the outdoor heat exchanger 231. To throttle the valve here means to reduce the opening of the valve.

The refrigerant amount determination unit 493 determines the determination result as one of expansion valve opening degree large, supercooling degree large, and abnormality non-detection in each abnormality determination.
The expansion valve opening degree large indicates that the opening degree of the determination target expansion valve is larger than a predetermined threshold value. The large opening of the expansion valve indicates that the refrigerant in the receiver tank 241 is insufficient.
When the receiver tank 241 has a shortage of refrigerant, such as when the receiver tank 241 is empty, the refrigerant flowing through the indoor heat exchanger 311 is insufficient and cannot be cooled to the target temperature. Then, the control unit 490 increases the opening degree of the indoor unit side expansion valve 312 in order to increase the refrigerant flowing through the indoor heat exchanger 311. In addition, the control unit 490 increases the opening degree of the supercooling side expansion valve 252 in preparation for an increase in refrigerant flowing from the outdoor unit 200 to the outdoor unit 200.

  However, when the refrigerant in the receiver tank 241 is insufficient, the refrigerant flowing through the indoor heat exchanger 311 does not increase even if the opening degree of the indoor unit side expansion valve 312 is increased. Temperature does not drop. For this reason, the control unit 490 further increases the opening degree of the indoor unit side expansion valve 312 and the opening degree of the supercooling side expansion valve 252. Thus, in a state where the refrigerant in the receiver tank 241 is insufficient, the control unit 490 increases the opening degree of the indoor unit side expansion valve 312 and the opening degree of the supercooling side expansion valve 252, thereby determining the object of determination. The opening degree of the expansion valve becomes larger than the threshold value. As described above, the determination target expansion valve is one or both of the indoor unit side expansion valve 312 and the supercooling side expansion valve 252.

A large degree of supercooling indicates that the degree of supercooling of the outdoor heat exchanger 231 is greater than a predetermined threshold. This large degree of supercooling indicates that the refrigerant overflows from the receiver tank 241. Here, the refrigerant overflowing from the receiver tank 241 means that the receiver tank 241 is full and cannot accommodate the refrigerant. When the refrigerant overflows from the receiver tank 241, the overflowed refrigerant accumulates in the outdoor heat exchanger 231, thereby increasing the degree of supercooling of the outdoor heat exchanger 231. The receiver tank 241 determines that the degree of supercooling is large when the degree of supercooling of the outdoor heat exchanger 231 increases and becomes larger than the threshold value.
Abnormality non-detection indicates that neither the expansion valve opening degree nor the supercooling degree is detected.

In the example of FIG. 4, when the refrigerant amount determination unit 493 determines that the abnormality is not detected by the abnormality determination in the normal state and determines that the expansion valve opening is large by the abnormality determination after the degree of supercooling increases, the air conditioning system main body It is determined that the amount of the refrigerant sealed in 100 is appropriate.
The abnormality determination result after the increase in the degree of supercooling in this case indicates that the refrigerant in the receiver tank 241 is insufficient with the refrigerant stored in the outdoor heat exchanger 231 intentionally. From this result, in a normal state in which the refrigerant is not intentionally stored in the outdoor heat exchanger 231, the refrigerant does not overflow from the receiver tank 241 even if the amount of refrigerant in the receiver tank 241 changes due to environmental changes or the like. Be expected. In this case, the amount by which the supercooling degree adjustment unit 492 increases the supercooling degree can be adjusted in advance so that an appropriate determination result can be obtained.

In addition, when the refrigerant amount determination unit 493 determines that the abnormality is not detected or the degree of supercooling is large in the abnormality determination in the normal state and determines that the abnormality is not detected in the abnormality determination after the degree of supercooling is increased, the air conditioning system main body It is determined that the amount of the refrigerant sealed in 100 is excessive.
When the abnormality determination result in the normal state is that the degree of supercooling is large, it is considered that the refrigerant overflows from the receiver tank 241 as described above. Therefore, the refrigerant amount determination unit 493 determines that the amount of refrigerant enclosed in the air conditioning system main body 100 is excessive.
Further, when the abnormality determination result after the increase in the degree of supercooling is abnormality non-detection, there is a possibility that the refrigerant overflows from the receiver tank 241 in a normal state where the refrigerant is not intentionally stored in the outdoor heat exchanger 231. Therefore, the refrigerant amount determination unit 493 determines that the amount of refrigerant enclosed in the air conditioning system main body 100 is excessive.

In addition, when the refrigerant amount determination unit 493 determines that the expansion valve opening degree is large in the normal state abnormality determination and determines that the expansion valve opening degree is large in the abnormality determination after the degree of supercooling is increased, the air conditioning system main body 100 It is determined that the amount of the refrigerant sealed in is excessive.
When the abnormality determination result in the normal state is that the expansion valve opening is large, it is considered that the refrigerant in the receiver tank 241 is insufficient as described above. Therefore, the refrigerant amount determination unit 493 determines that the amount of refrigerant enclosed in the air conditioning system main body 100 is too small.

The refrigerant amount determination unit 493 may determine whether or not the amount of refrigerant is appropriate based on the processing shown in FIG.
FIG. 5 is a flowchart illustrating an example of a processing procedure in a case where the control device 400 determines whether or not the refrigerant amount is appropriate based on the data at the two-stage supercooling degree.
(Step S101)
The control unit 490 sets the operation mode of the air conditioning system main body 100 to the normal operation mode of the cooling cycle. Based on this setting, the control unit 490 controls the air conditioning system main body 100 to operate in a cooling cycle and in a normal state. As described above, the normal state is a state in which control for restricting the outdoor expansion valve 232 is not performed in order to increase the degree of supercooling of the outdoor heat exchanger 231.
After step S101, the process proceeds to step S102.

(Step S102)
The refrigerant amount determination unit 493 performs abnormality determination. The abnormality determination here corresponds to the abnormality determination in the normal state.
If it is determined that no abnormality has been detected (step S102: no abnormality detected), the process proceeds to step S111. When it is determined that the degree of supercooling is high (step S102: high degree of supercooling), the process proceeds to step S131. When it is determined that the expansion valve opening is large (step S102: expansion valve opening is large), the process proceeds to step S141.

(Step S111)
The supercooling degree adjusting unit 492 increases the supercooling degree of the outdoor heat exchanger 231 by restricting the outdoor expansion valve 232.
After step S111, the process proceeds to step S112.
(Step S112)
The refrigerant amount determination unit 493 performs abnormality determination. The abnormality determination here corresponds to the abnormality determination after the degree of supercooling is increased.
When it is determined that the expansion valve opening is large (step S121: expansion valve opening is large), the process proceeds to step S121. If it is determined that the abnormality is not detected, or if it is determined that the degree of supercooling is large (step S121: abnormality is not detected or the degree of supercooling is large), the process proceeds to step S131.

(Step S121)
The refrigerant amount determination unit 493 determines that the amount of refrigerant sealed in the air conditioning system main body 100 is appropriate.
After step S121, the process in FIG.
(Step S131)
The refrigerant amount determination unit 493 determines that the amount of refrigerant enclosed in the air conditioning system main body 100 is excessive.
After step S131, the process of FIG.
(Step S141)
The refrigerant amount determination unit 493 determines that the amount of refrigerant enclosed in the air conditioning system main body 100 is too small.
After step S141, the process of FIG.

FIG. 6 is a flowchart illustrating an example of a processing procedure in which the control device 400 increases the degree of supercooling of the outdoor heat exchanger 231. The control device 400 performs the process of FIG. 6 in step S111 of FIG.
(Step S201)
The information acquisition unit 491 acquires outdoor heat exchanger outlet temperature information from the outdoor heat exchanger outlet temperature sensor 292 via the communication unit 410. The outdoor heat exchanger outlet temperature information is information indicating a temperature measurement value of the outdoor heat exchanger outlet temperature sensor 292. This outdoor heat exchanger outlet temperature information indicates the outlet temperature of the outdoor heat exchanger 231 in the cooling cycle.
After step S201, the process proceeds to step S202.

(Step S202)
The information acquisition unit 491 acquires outdoor heat exchanger pressure saturation temperature information from the high-pressure side pressure sensor 291 via the communication unit 410. The outdoor heat exchanger pressure saturation temperature information is information calculated from the pressure measurement value of the high-pressure side pressure sensor 291. This outdoor heat exchanger pressure saturation temperature information indicates the pressure saturation temperature in the outdoor heat exchanger 231.
After step S202, the process proceeds to step S203.

(Step S203)
The information acquisition unit 491 calculates the degree of supercooling of the outdoor heat exchanger 231. Specifically, the refrigerant amount determination unit 493 calculates the difference between the outlet temperature of the outdoor heat exchanger 231 indicated by the outdoor heat exchanger outlet temperature information and the pressure saturation temperature indicated by the outdoor heat exchanger pressure saturation temperature information. .
After step S203, the process proceeds to step S204.

(Step S204)
The supercooling degree adjusting unit 492 sets a control target value for controlling the opening degree of the outdoor expansion valve 232 based on the supercooling degree obtained in step S203. For example, the supercooling degree adjustment unit 492 sets a target value for increasing the supercooling degree of the outdoor heat exchanger 231 by a predetermined temperature.
After step S204, the process proceeds to step S205.

(Step S205)
The supercooling degree adjustment unit 492 performs control to reduce the opening degree of the outdoor expansion valve 232. For example, the supercooling degree adjusting unit 492 decreases the opening degree of the outdoor expansion valve 232 by a predetermined opening degree.
After step S205, the process proceeds to step S206.
(Step S206)
The supercooling degree adjustment unit 492 determines whether or not the target value set in step S204 has been reached.
If it is determined that the target value has not been reached (step S206: NO), the process returns to step S205. If it is determined that the target value has been reached (step S206: YES), the processing in FIG. 6 is terminated.

The refrigerant amount determination unit 493 may determine whether or not the refrigerant amount is appropriate based on data at three or more levels of supercooling.
FIG. 7 is a diagram illustrating an example of a determination criterion when the refrigerant amount determination unit 493 determines whether or not the refrigerant amount is appropriate based on data at three stages of supercooling degrees. In the example of FIG. 7, the refrigerant amount determination unit 493 is a refrigerant sealed in the air conditioning system main body 100 based on the abnormality determination results in the first supercooling degree, the second supercooling degree, and the third supercooling degree. Determine whether the amount is appropriate, excessive or insufficient.

  The first degree of supercooling is the degree of supercooling in the normal state. Therefore, the first degree of supercooling is the degree of supercooling in a state in which control for restricting the outdoor expansion valve 232 is not performed in order to increase the degree of supercooling of the outdoor heat exchanger 231. The second supercooling degree is a supercooling degree larger than the first supercooling degree. The third degree of supercooling is a degree of supercooling that is greater than the second degree of supercooling.

  In the example of FIG. 7, the supercooling degree adjustment unit 492 changes the supercooling degree of the outdoor heat exchanger 231 to each of the first supercooling degree, the second supercooling degree, and the third supercooling degree. The refrigerant amount determination unit 493 is based on the degree of opening of the determination target expansion valve and the degree of supercooling of the outdoor heat exchanger 231 in each of the first degree of subcooling, the second degree of subcooling, and the degree of third supercooling. It is determined whether the refrigerant amount of the air conditioning system 1 is appropriate. Or you may make it the supercooling degree adjustment part 492 determine whether the refrigerant | coolant amount of the air conditioning system 1 is appropriate based only on the opening degree of a determination object expansion valve. That is, the supercooling degree adjusting unit 492 may perform the determination without using the information on the supercooling degree of the outdoor heat exchanger 231.

In the example of FIG. 7, the supercooling degree adjustment unit 492 changes the supercooling degree of the outdoor heat exchanger 231 in three stages, and the refrigerant amount determination unit 493 is replaced with the determination criterion shown in FIG. 4. 7 is different from the case of FIG. 4 in that the determination is performed using the determination criteria shown in FIG. The rest is the same as in FIG.
In the example of FIG. 7, the refrigerant amount determination unit 493 determines that the abnormality is not detected in the abnormality determination in the first subcooling degree, determines that the abnormality is not detected in the abnormality determination in the second subcooling degree, and the third subcooling When it is determined that the expansion valve opening degree is large in the abnormality determination in degree, it is determined that the amount of the refrigerant sealed in the air conditioning system main body 100 is appropriate.

On the other hand, the refrigerant amount determination unit 493 determines that the abnormality is not detected or the degree of supercooling is high in the abnormality determination in the first supercooling degree, and determines that the abnormality is not detected or the degree of supercooling is high in the abnormality determination in the second supercooling degree. And when it determines with abnormality non-detecting by abnormality determination in a 3rd supercooling degree, it determines with the quantity of the refrigerant | coolant enclosed with the air conditioning system main body 100 being excessive.
The refrigerant amount determination unit 493 determines that the abnormality is not detected or the expansion valve opening is large in the abnormality determination in the first subcooling degree, determines that the expansion valve opening is large in the abnormality determination in the second subcooling degree, and When it is determined that the expansion valve opening degree is large in the abnormality determination in the third supercooling degree, it is determined that the amount of the refrigerant sealed in the air conditioning system main body 100 is too small.

  In particular, when the refrigerant amount determination unit 493 determines that the degree of supercooling is large in the abnormality determination in the first subcooling degree, the refrigerant sealed in the air conditioning system main body 100 is the same as described in the example of FIG. Is determined to be excessive. Further, when it is determined that the expansion valve opening degree is large in the abnormality determination in the first supercooling degree, the refrigerant amount determination unit 493 is enclosed in the air conditioning system main body 100 as described in the example of FIG. It determines with the quantity of a refrigerant | coolant being too small.

The second degree of supercooling is a degree of supercooling set to distinguish between a case where the amount of refrigerant is particularly appropriate and a case where the amount of refrigerant is too small. The second degree of supercooling is set to a degree of supercooling that is smaller than the degree of supercooling after the increase in degree of supercooling in the example of FIG.
When the refrigerant amount determination unit 493 determines that the expansion valve opening degree is large in the abnormality determination in the second subcooling degree, the air conditioning is similar to the case where it is determined in the abnormality determination in the first subcooling degree that the expansion valve opening degree is large. It determines with the quantity of the refrigerant | coolant enclosed with the system main body 100 being too small.

The third degree of supercooling is a degree of supercooling set to distinguish between a case where the amount of refrigerant is particularly appropriate and a case where the amount of refrigerant is excessive. The third supercooling degree is set to the same supercooling degree as the supercooling degree after the supercooling degree increase in the example of FIG.
When the refrigerant amount determination unit 493 determines that the abnormality is not detected in the abnormality determination in the third supercooling degree, the amount of the refrigerant sealed in the air conditioning system main body 100 is the same as described in the example of FIG. It is determined that there are too many.

The refrigerant amount determination unit 493 may determine whether or not the amount of refrigerant is appropriate based on the processing shown in FIG.
FIG. 8 is a flowchart illustrating an example of a processing procedure in the case where the control device 400 determines whether or not the refrigerant amount is appropriate based on data at three stages of supercooling degrees.
Steps S301 to S302 are the same as steps S101 to S102 in FIG. The abnormality determination in step S301 corresponds to the abnormality determination in the first supercooling degree.
If it is determined in step S302 that no abnormality is detected (step S302: no abnormality detected), the process proceeds to step S311. When it is determined that the degree of supercooling is high (step S302: high degree of supercooling), the process proceeds to step S341. When it is determined that the expansion valve opening is large (step S302: expansion valve opening is large), the process proceeds to step S351.

(Step S311)
The supercooling degree adjusting unit 492 increases the supercooling degree of the outdoor heat exchanger 231 by restricting the outdoor expansion valve 232. In step S311, the control device 400 performs the process of FIG. 6 so that the supercooling degree adjusting unit 492 increases the supercooling degree of the outdoor heat exchanger 231. In step S311, the supercooling degree adjusting unit 492 sets the supercooling degree of the outdoor heat exchanger 231 to the second supercooling degree.
After step S311, the process proceeds to step S312.

(Step S312)
The refrigerant amount determination unit 493 performs abnormality determination. The abnormality determination here corresponds to the abnormality determination in the second supercooling degree.
If it is determined that no abnormality is detected (step S312: no abnormality detected), the process proceeds to step S321. If it is determined that the degree of supercooling is high (step S312: high degree of supercooling), the process proceeds to step S341. If it is determined that the expansion valve opening is large (step S312: expansion valve opening is large), the process proceeds to step S351.

(Step S321)
The supercooling degree adjusting unit 492 increases the supercooling degree of the outdoor heat exchanger 231 by restricting the outdoor expansion valve 232. In step S321, the control device 400 performs the process of FIG. 6 so that the supercooling degree adjustment unit 492 increases the supercooling degree of the outdoor heat exchanger 231. In step S321, the supercooling degree adjusting unit 492 sets the supercooling degree of the outdoor heat exchanger 231 to the third supercooling degree.
After step S321, the process proceeds to step S322.

(Step S322)
The refrigerant amount determination unit 493 performs abnormality determination. The abnormality determination here corresponds to the abnormality determination in the third supercooling degree.
When it is determined that the expansion valve opening is large (step S322: expansion valve opening is large), the process proceeds to step S331. If it is determined that the abnormality is not detected, or if it is determined that the degree of supercooling is large (step S322: abnormality is not detected or the degree of supercooling is large), the process proceeds to step S341.

(Step S331)
The refrigerant amount determination unit 493 determines that the amount of refrigerant sealed in the air conditioning system main body 100 is appropriate.
After step S331, the process of FIG.
(Step S341)
The refrigerant amount determination unit 493 determines that the amount of refrigerant enclosed in the air conditioning system main body 100 is excessive.
After step S341, the process of FIG. 8 ends.
(Step S351)
The refrigerant amount determination unit 493 determines that the amount of refrigerant enclosed in the air conditioning system main body 100 is too small.
After step S351, the process of FIG.

As described above, the supercooling degree adjusting unit 492 increases the supercooling degree of the outdoor heat exchanger 231. The refrigerant amount determination unit 493 is a refrigerant of the air-conditioning system 1 based on the opening degree of the determination target expansion valve before increasing the degree of supercooling and the opening degree of the determination target expansion valve after increasing the degree of supercooling. Determine if the amount is appropriate.
If the control device 400 determines whether or not the amount of refrigerant in the air-conditioning system 1 is appropriate based only on information in a state where the degree of supercooling of the outdoor heat exchanger 231 is not increased, the receiver tank 241 It is not possible to determine how much refrigerant can be accommodated.
On the other hand, the control apparatus 400 can increase the supercooling degree of the outdoor heat exchanger 231, so that the refrigerant is intentionally stored in the outdoor heat exchanger 231 and the amount of refrigerant in the receiver tank 241 can be reduced. By performing the determination in this state, the control device 400 can determine whether or not the receiver tank 241 can accommodate a sufficient amount of refrigerant in a state where the degree of supercooling of the outdoor heat exchanger 231 is not increased. it can. Therefore, the control device 400 can determine the possibility that the refrigerant overflows from the receiver tank 241 when the amount of refrigerant in the receiver tank 241 increases due to environmental changes or the like.
In this respect, the control device 400 determines whether or not the amount of refrigerant in the air-conditioning system 1 is more appropriate than when determining based on only information in a state where the degree of supercooling of the outdoor heat exchanger 231 is not increased. Can be determined with high accuracy.
The supercooling degree adjustment unit 492 can increase the supercooling degree of the outdoor heat exchanger 231 by reducing the opening degree of the outdoor expansion valve 232.

Moreover, the refrigerant | coolant amount determination part 493 is suitable for the refrigerant | coolant amount of the air conditioning system 1 based on the degree of subcooling of the outdoor heat exchanger 231 before increasing a degree of supercooling in addition to the opening degree of a determination object expansion valve. It is determined whether or not.
Thereby, the refrigerant | coolant amount determination part 493 can determine whether the refrigerant | coolant amount of the air conditioning system 1 is too small.

The supercooling degree adjusting unit 492 changes the supercooling degree of the outdoor heat exchanger 231 to each of the first supercooling degree, the second supercooling degree, and the third supercooling degree. The refrigerant amount determination unit 493 determines whether the refrigerant amount of the air conditioning system 1 is appropriate based on the opening degree of the determination target expansion valve in each of the first subcooling degree, the second subcooling degree, and the third supercooling degree. Judgment is made.
The refrigerant amount determination unit 493 determines whether or not the refrigerant amount is insufficient when the refrigerant amount in the receiver tank 241 decreases to some extent from the refrigerant amount in the normal state, using information in the case of the second supercooling degree. can do. Therefore, the refrigerant quantity determination unit 493 can determine whether or not the refrigerant quantity of the air conditioning system 1 is too small.
Further, the refrigerant amount determination unit 493 uses the information in the case of the third supercooling degree, and as described above, the receiver tank 241 has a sufficient capacity in a state where the supercooling degree of the outdoor heat exchanger 231 is not increased. It can be determined whether an amount of refrigerant can be accommodated.
In this regard, the control device 400 can determine whether or not the amount of refrigerant in the air conditioning system 1 is appropriate with higher accuracy.

It should be noted that a program for realizing all or part of the functions of the control unit 490 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed. You may perform the process of. Here, the “computer system” includes an OS and hardware such as peripheral devices.
Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used.
The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes design changes and the like without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Air conditioning system 100 Air conditioning system main body 200 Outdoor unit 211 Compressor 212 Accumulator 221 Four-way valve 231 Outdoor heat exchanger 232 Outdoor expansion valve 241 Receiver tank 251 Supercooling heat exchanger 252 Supercooling side expansion valve 291 High pressure side pressure sensor 292 Outdoor heat exchanger outlet temperature sensor 300 Indoor unit 311 Indoor heat exchanger 312 Indoor unit side expansion valve 400 Controller 410 Communication unit 420 Operation input unit 430 Display unit 480 Storage unit 490 Control unit 491 Information acquisition unit 492 Supercooling degree adjustment Part 493 Refrigerant amount determination part

Claims (7)

An information acquisition unit that acquires expansion valve opening information indicating an opening of a determination target expansion valve that is at least one of an expansion valve of an indoor unit provided in the air conditioning system or an expansion valve on a subcooling heat exchanger side;
A supercooling degree adjusting unit for increasing the supercooling degree of the outdoor heat exchanger provided in the air conditioning system;
Based on the opening of the determination target expansion valve before increasing the degree of supercooling and the opening of the determination target expansion valve after increasing the degree of supercooling, the refrigerant amount of the air conditioning system is appropriate. A refrigerant amount determination unit for determining whether or not,
A refrigerant quantity determination device comprising: The supercooling degree adjustment unit increases the supercooling degree by reducing the opening of the expansion valve on the outdoor heat exchanger side included in the air conditioning system.
The refrigerant quantity determination device according to claim 1. The refrigerant amount determination unit further determines whether or not the refrigerant amount of the air conditioning system is appropriate based on the subcooling degree before the supercooling degree adjustment unit increases the supercooling degree.
The refrigerant quantity determination device according to claim 1 or 2. The supercooling degree adjustment unit sets the supercooling degree to a first supercooling degree, a second supercooling degree larger than the first supercooling degree, and a third supercooling degree larger than the second supercooling degree Change to
The refrigerant amount determination unit is configured to determine a refrigerant amount of the air conditioning system based on an opening degree of the determination target expansion valve in each of the first subcooling degree, the second subcooling degree, and the third subcooling degree. To determine whether or not
The refrigerant quantity determination device according to any one of claims 1 to 3.   An air conditioning system provided with the refrigerant | coolant amount determination apparatus as described in any one of Claim 1 to 4. Increasing the degree of subcooling of the outdoor heat exchanger provided in the air conditioning system,
Before increasing the degree of supercooling, increase the degree of opening of the judgment target expansion valve that is at least one of the expansion valve of the indoor unit provided in the air conditioning system or the expansion valve on the side of the supercooling heat exchanger, and the degree of supercooling And determining whether or not the refrigerant amount of the air-conditioning system is appropriate based on the opening degree of the determination target expansion valve after the determination. To the computer that controls the air conditioning system,
Control to increase the degree of supercooling of the outdoor heat exchanger provided in the air conditioning system,
Before increasing the degree of supercooling, increase the degree of opening of the judgment target expansion valve that is at least one of the expansion valve of the indoor unit provided in the air conditioning system or the expansion valve on the side of the supercooling heat exchanger, and the degree of supercooling A program for making a determination as to whether or not the amount of refrigerant in the air-conditioning system is appropriate based on the opening degree of the determination target expansion valve after the determination.

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