JP2019086252A - Control device of multi-type air conditioning device, multi-type air conditioning device, control method of multi-type air conditioning device, and control program of multi-type air conditioning device - Google Patents

Abstract

To provide a control device of a multi-type air conditioning device, the multi-type air conditioning device, a control method of the multi-type air conditioning device, and a control program of the multi-type air conditioning device in which a refrigerant is adjusted by controlling an amount of required refrigerant which is fluctuated.SOLUTION: A control device 70 of a multi-type air conditioning device 1 including at least one outdoor unit 2 having a plurality of circuits respectively composed of an outdoor-side four-way switch valve 12, an outdoor heat exchanger 13, and an outdoor electronic expansion valve 15, and a plurality of indoor units 3, performs control to switch the outdoor-side four-way switch valve 12 corresponding to the outdoor heat exchanger 13 in a stopped state, in a case when difference between an outlet temperature of an indoor heat exchanger 30 disposed in the indoor unit 3 and a temperature of a central portion is first temperature difference or less, and an excessive refrigerant amount is detected in a state that all of the outdoor electronic expansion valves 15 of at least one circuit are fully closed, and the outdoor heat exchanger 13 is in a stopped state.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a control device of a multi-type air conditioner, a multi-type air conditioner, a control method of the multi-type air conditioner, and a control program of the multi-type air conditioner.

  In the multi-type air conditioner, the required amount of refrigerant fluctuates depending on operating conditions such as cooling and heating, and air conditions such as temperature and humidity. Further, in the multi-type air conditioner, in addition to the above-mentioned conditions, the required refrigerant quantity also fluctuates depending on the number of indoor units operated. An appropriate amount of refrigerant is supplied to the operating indoor unit, but if the amount of supply is not appropriate, there is a risk that the capacity of the operating indoor unit may decrease due to excessive or insufficient amount of refrigerant. is there.

Generally, in order to cope with the fluctuating necessary amount of refrigerant, adjustment of the refrigerant is performed by storing the refrigerant in the receiver when the amount of refrigerant is excessive and recovering the refrigerant from the receiver when the amount of refrigerant is insufficient.
For example, Patent Document 1 discloses that a liquid refrigerant is stored in a receiver.

JP, 2006-177619, A

However, in the invention disclosed in Patent Document 1, there is an upper limit to the storage amount of the receiver, and therefore, when an excessive amount of refrigerant exceeding the volume of the receiver occurs, there is a problem that the capability of the multi-type air conditioner decreases. there were.
In addition, in the case of adjusting the refrigerant by storing in the receiver, it is necessary to adjust the volume of the receiver to the fluctuation of the amount of refrigerant, and the problem is solved by increasing the volume of the receiver. However, the size of the outdoor unit is limited, and there is a problem that increasing the receiver volume leads to an increase in cost, such as redesign of the outdoor unit or size increase of the outdoor unit.

  The present invention has been made in view of such circumstances, and is a control device for a multi-type air conditioner, which adjusts the refrigerant by control with respect to a fluctuating required refrigerant amount, a multi-type air conditioner, and a multi-type air It is an object of the present invention to provide a control method of a conditioning device and a control program of a multi-type air conditioning device.

In order to solve the above-mentioned subject, a control device of a multi type air conditioner of the present invention, a multi type air conditioner, a control method of a multi type air conditioner, and a control program of a multi type air conditioner adopt the following means .
A controller for a multi-type air conditioner according to a first aspect of the present invention includes at least one outdoor unit having a plurality of circuits including a four-way switching valve, an outdoor heat exchanger, and an outdoor electronic expansion valve, and a plurality of indoors. Control device for a multi-type air conditioner including: an indoor unit when the outdoor electronic expansion valve of at least one of the circuits is fully closed and the outdoor heat exchanger is in a stop state When it is detected that the difference between the outlet temperature of the indoor heat exchanger and the central part temperature provided in the unit is equal to or less than the first temperature difference and the amount of refrigerant is excessive, this corresponds to the outdoor heat exchanger in the stopped state. Control is performed to switch the four-way switching valve.

According to this aspect, there is provided a multi-type air conditioner including: at least one outdoor unit having a plurality of circuits including a four-way switching valve, an outdoor heat exchanger, and an outdoor electronic expansion valve, and a plurality of indoor units. A control device, wherein the outdoor electronic expansion valve of at least one of the circuits is fully closed and the outdoor heat exchanger is in a stop state, and the outlet temperature of the indoor heat exchanger provided in the indoor unit When it is detected that the difference with the central portion temperature is equal to or less than the first temperature difference and the refrigerant amount is excessive, control is performed to switch the four-way switching valve corresponding to the outdoor heat exchanger in the stopped state, When the amount of refrigerant in the indoor unit becomes excessive and a decrease in performance is detected, the four-way switching valve corresponding to the outdoor heat exchanger in the stopped state is switched, and the refrigerant is stored in the outdoor heat exchanger in the stopped state.
When the required capacity for the outdoor unit is not large and the required capacity can be satisfied by the operation of only some of the outdoor heat exchangers, the other outdoor heat exchangers can be stopped. In that case, the outdoor heat exchanger is brought into a stopped state by the corresponding outdoor electronic expansion valve being fully closed, and in addition to cooling, the four-way switching valve is switched.
When the circulating refrigerant tends to be excessive, the refrigerant is stored in the receiver of the outdoor unit. However, when the refrigerant exceeds the storage amount of the receiver and is further excessively, the refrigerant amount of the indoor unit becomes excessive and the capacity is lowered. Whether or not the refrigerant amount is excessive can be detected when the difference between the outlet temperature of the indoor heat exchanger provided in the indoor unit and the central portion temperature becomes equal to or less than the first temperature difference. This is because the receiver overflows and the refrigerant becomes excessive, the refrigerant is stored in the indoor heat exchanger of the indoor unit, and the difference between the outlet temperature and the central portion temperature becomes substantially the same.
Although the outdoor heat exchanger in the stopped state is stopped as described above, when the control device detects an excessive amount of refrigerant, the control device controls the switching of the four-way switching valve corresponding to the outdoor heat exchanger in the stopped state. Do.
As a result, the refrigerant is stored in the outdoor heat exchanger in the stopped state, and an appropriate amount of refrigerant is supplied to the indoor unit, so that the capacity can be prevented from decreasing. In addition, since the amount of refrigerant can be adjusted by control of the four-way switching valve, it is not necessary to increase the capacity of the receiver of the outdoor unit, which leads to cost reduction. In the installation of a multi-type air conditioner, the charge amount of the refrigerant is determined by the number of indoor units and the refrigerant pipe length, but since the refrigerant amount can be adjusted by control of the four-way switching valve, the charge amount is appropriate Even if it is set more than it is acceptable.
In addition, since the indoor heat exchanger is not used for storing the refrigerant, there is no influence on the indoor environment such as overheating.

  In the first aspect, each of the indoor units includes an indoor electronic expansion valve, and the outdoor heat exchanger is a condenser when refrigerant is stored in the outdoor heat exchanger in at least one stopped state. When the opening degree of the indoor electronic expansion valve of the indoor unit is equal to or more than the first predetermined opening degree, and when the outdoor heat exchanger is an evaporator, the opening degree of the outdoor electronic expansion valve of the outdoor unit is second predetermined When it is detected that the opening degree of the indoor electronic expansion valve corresponding to the indoor unit at the opening degree or higher or during the cooling operation becomes equal to or higher than the first predetermined opening degree and the refrigerant amount is insufficient, any one stop state Control may be performed to adjust the closed outdoor electronic expansion valve corresponding to the outdoor heat exchanger in which the refrigerant is stored in the opening direction.

According to this aspect, when the refrigerant is stored in the outdoor heat exchanger in at least one stopped state, the opening of the indoor electronic expansion valve of the indoor unit is performed when the outdoor heat exchanger is a condenser. When the outdoor heat exchanger is an evaporator, the opening degree of the outdoor electronic expansion valve of the outdoor unit corresponds to the indoor unit during the cooling operation or more. When it is detected that the opening degree of the indoor electronic expansion valve becomes equal to or more than the first predetermined opening degree and the amount of refrigerant is insufficient, the outdoor heat exchanger is in any one stopped state and the refrigerant is stored. Since the control is performed to adjust the corresponding closed outdoor electronic expansion valve in the opening direction, the refrigerant is stored in the outdoor heat exchanger by switching the four-way switching valve, so the amount of refrigerant in the indoor unit runs short and the capacity decreases. When one of the refrigerants is detected Adjusting the outdoor electronic expansion valve corresponding to the outdoor heat exchanger that is stored in the opening direction, for example, performs control to BiHiraku, recovering the refrigerant stored in the outdoor heat exchanger. Thereby, the amount of refrigerant in the indoor unit can be corrected. Further, by repeating this correction, an appropriate amount of refrigerant is supplied to the indoor unit, and the operation of the multi-type air conditioner can be stabilized.
In addition, although the outdoor heat exchanger has a large capacity, it is easy to store the refrigerant, but there is a possibility that the refrigerant is stored too much, but the refrigerant amount can be adjusted by performing the control to slightly open the refrigerant.
When the outdoor heat exchanger is a condenser, the opening degree of the indoor electronic expansion valve of the indoor unit is equal to or greater than the first predetermined opening, and when the outdoor heat exchanger is an evaporator, the outdoor electronic expansion valve of the outdoor unit When the opening degree of the indoor electronic expansion valve corresponding to the indoor unit having the opening degree equal to or more than the second predetermined opening degree or the cooling operation becomes equal to or more than the first predetermined opening degree, the amount of refrigerant in the indoor unit is insufficient Since the detection of the amount of refrigerant in the indoor unit can be detected by a simple method.
When an appropriate amount of refrigerant is supplied to the indoor unit, the electronic expansion valve of the evaporator, that is, when the outdoor heat exchanger is a condenser, the indoor electronic expansion valve of the indoor unit, and the outdoor heat exchanger is an evaporator The outdoor electronic expansion valve of the outdoor unit or the indoor electronic expansion valve corresponding to the indoor unit during the cooling operation has a predetermined opening degree. When the amount of refrigerant in the indoor unit is insufficient, it is necessary to circulate a larger amount of refrigerant. Therefore, when the outdoor heat exchanger is a condenser, the indoor electronic expansion valve of the indoor unit and the outdoor heat exchanger are an evaporator. The opening degree of the outdoor electronic expansion valve of the outdoor unit or the opening degree of the indoor electronic expansion valve corresponding to the indoor unit in the cooling operation becomes equal to or more than the predetermined opening degree. Here, the first predetermined opening degree is, for example, the maximum opening degree of the indoor electronic expansion valve, and the second predetermined opening degree is, for example, the maximum opening degree of the outdoor electronic expansion valve.

  In the first aspect, the indoor heat exchanger provided in the indoor unit when the outdoor electronic expansion valve corresponding to the outdoor heat exchanger in at least one stopped state and in which the refrigerant is stored is open. When it is detected that the difference between the outlet temperature and the central portion temperature is equal to or less than the first temperature difference and the refrigerant amount is excessive, control for adjusting the outdoor electronic expansion valve corresponding to the outdoor heat exchanger in the closing direction is performed. You may do it.

  According to this aspect, the indoor heat exchanger provided in the indoor unit when the outdoor electronic expansion valve corresponding to the outdoor heat exchanger in at least one stopped state and in which the refrigerant is stored is open. When it is detected that the difference between the outlet temperature and the central portion temperature is equal to or less than the first temperature difference and the refrigerant amount is excessive, control for adjusting the outdoor electronic expansion valve corresponding to the outdoor heat exchanger in the closing direction is performed. Do. The refrigerant is stored in the outdoor heat exchanger by switching the four-way switching valve, so the amount of refrigerant in the indoor unit runs short and the outdoor electronic expansion valve is opened. However, this is applicable when the amount of collected refrigerant is large and the amount of refrigerant is excessive. Control is performed to adjust the outdoor electronic expansion valve corresponding to the outdoor heat exchanger in the closing direction to reduce the amount of refrigerant to be collected, or to store the refrigerant in the outdoor heat exchanger. Thereby, the amount of refrigerant in the indoor unit can be corrected. Further, by repeating this correction, an appropriate amount of refrigerant is supplied to the indoor unit, and the operation of the multi-type air conditioner can be stabilized.

  In the first aspect, the state in which the difference between the set temperature of one or more indoor units and the indoor temperature is the second temperature difference or more continues for a predetermined time or longer, and the indoor heat exchange provided in the indoor unit The indoor unit may detect that the amount of refrigerant is excessive when the difference between the outlet temperature of the unit and the central portion temperature is equal to or less than the first temperature difference.

  According to this aspect, the state in which the difference between the set temperature of the one or more indoor units and the indoor temperature is the second temperature difference or more continues for the predetermined time or longer, and the indoor heat exchange provided in the indoor unit If the difference between the outlet temperature of the unit and the central portion temperature is equal to or less than the first temperature difference, it is detected that the indoor unit is in excess of the refrigerant amount. The state in which the difference between the set temperature of the indoor unit and the room temperature is equal to or greater than the second temperature difference means that the difference between the set temperature set by the user using the indoor controller or the like and the actual room temperature is large. . If this continues for a predetermined time or more, it can be said that the multi-type air conditioner is not warm in the case of heating, and is not cool in the case of cooling. If the difference between the outlet temperature of the indoor heat exchanger and the central temperature provided in the indoor unit is less than or equal to the first temperature difference, the receiver overflows and the refrigerant becomes excessive, causing the indoor heat exchanger of the indoor unit to This means that the refrigerant is stored and the difference between the outlet temperature and the central temperature is substantially the same. Therefore, when the indoor unit is in the unheated or uncooled state and the refrigerant amount is excessive, it is detected that the refrigerant amount of the indoor unit is excessive. This makes it possible to prevent unnecessary control without frequent setting changes.

  A multi-type air conditioner according to a second aspect of the present invention includes: the control device described above; and at least one outdoor unit having a plurality of circuits configured of a four-way switching valve, an outdoor heat exchanger, and an outdoor electronic expansion valve. And a plurality of indoor units.

  A control method of a multi-type air conditioner according to a third aspect of the present invention includes at least one outdoor unit having a plurality of circuits including a four-way switching valve, an outdoor heat exchanger, and an outdoor electronic expansion valve, and a plurality of indoors. And controlling the outdoor electronic expansion valve of at least one of the circuits while the outdoor heat exchanger is in a stopped state. When it is detected that the difference between the outlet temperature of the indoor heat exchanger and the central part temperature provided in the unit is equal to or less than the first temperature difference and the amount of refrigerant is excessive, this corresponds to the outdoor heat exchanger in the stopped state. Switching the four-way switching valve.

  A control program for a multi-type air conditioner according to a fourth aspect of the present invention includes at least one outdoor unit having a plurality of circuits configured of a four-way switching valve, an outdoor heat exchanger, and an outdoor electronic expansion valve, and a plurality of indoors. And controlling the outdoor electronic expansion valve of at least one of the circuits when the outdoor heat exchanger is in a stop state. When it is detected that the difference between the outlet temperature of the indoor heat exchanger and the central part temperature provided in the unit is equal to or less than the first temperature difference and the amount of refrigerant is excessive, this corresponds to the outdoor heat exchanger in the stopped state. Switching the four-way switching valve.

  According to the present invention, since the proper amount of refrigerant is obtained by the control of the four-way switching valve, it is possible to suppress the decrease in the capacity of the indoor unit by the simple control.

It is the schematic block diagram which showed the multi type air conditioning apparatus which concerns on one Embodiment of this invention. It is the flow chart which showed control at the time of refrigerant volume change of the multi type air harmony device concerning one embodiment of the present invention. It is the schematic which showed the indoor heat exchanger of the multi type air conditioning apparatus which concerns on one Embodiment of this invention. It is the graph which showed the relationship of the opening degree of the indoor electronic expansion valve of the multi-type air conditioning apparatus which concerns on one Embodiment of this invention, and flow volume.

Hereinafter, an embodiment of the present invention will be described using FIGS. 1 to 4.
The schematic block diagram of the multi type air conditioning apparatus which concerns on this embodiment is shown by FIG.
The multi-type air conditioning apparatus 1 of the present embodiment is also referred to as an air conditioning apparatus capable of simultaneous automatic operation of cooling and heating of a plurality of indoor units by one outdoor unit (also referred to as "cooling and heating simultaneous type""cooling and heating free". Hereinafter, it is also referred to as “simultaneous heating and cooling”.
The multi-type air conditioner 1 includes one outdoor unit 2, a plurality of (for example, five) indoor units 3A, 3B, 3C, 3D and 3E, a high pressure gas pipe 4H connecting them, and a low pressure gas pipe 4L. , A liquid side pipe 5, and a control device 70.
The outdoor unit 2 includes, for example, one compressor 10, two outdoor heat exchangers 13A and 13B, and two outdoor four-way switching valves (four-way switching valves) 12A and 12B.
In the following, the parts denoted as the outdoor heat exchangers 13A and 13B and the outdoor side four-way switching valves 12A and 12B etc. omit the reference numerals such as A and B unless specifically distinguished, for example, outdoor heat exchange It is shown as the vessel 13 and the outdoor side four-way switching valve 12.

In the present embodiment, the outdoor four-way switching valve 12 is provided corresponding to the outdoor heat exchanger 13, but the present invention is not limited to this. For example, the multi-type air conditioner 1 is provided with three outdoor heat exchangers 13 and two outdoor four-way switching valves 12, and one outdoor four-way switching valve 12 is connected with two outdoor heat exchangers 13, One remaining outdoor heat exchanger 13 may be connected to the other outdoor four-way switching valve 12.
Moreover, in this embodiment, although using a four-way switching valve as a refrigerant | coolant flow-path switching means is mentioned as an example and demonstrated, this invention is not limited to this, For example, two three-way valves are used. The same function as the four-way switching valve may be realized.
In the present embodiment, the multi-type air conditioner 1 is described by taking the case where five indoor units 3 are provided, but the number of indoor units 3 is not particularly limited.
Although FIG. 1 exemplifies the case where five indoor units 3A, 3B, 3C, 3D and 3E are installed, the number of installed units can be arbitrarily determined.
In the following description, when distinguishing each indoor unit 3, one of A, B, C, D or E is added to the end, and when not distinguishing each indoor unit 3, A, B, C, D Or omit E

  The outdoor heat exchanger 13 exchanges heat with outdoor air, is configured integrally with the subcooling coil 14, and operates as a condenser or an evaporator according to the state of the refrigerant passing therethrough. Between the outdoor heat exchangers 13A and 13B and the refrigerant piping 22 between the receiver 16, and in the vicinity of the outdoor heat exchangers 13A and 13B, outdoor electronic expansion valves (EEVH) 15A and 15B, respectively. Is provided.

The compressor 10 is operated according to the required capacity. The compressor 10 compresses the low-temperature low-pressure gas refrigerant from the outdoor heat exchanger 13 to produce a high-temperature high-pressure gas refrigerant.
The refrigerant compressed by the compressor 10 becomes a high pressure gas refrigerant and is discharged to the high pressure gas pipe 4H.

  The high pressure gas pipe 4H located in the outdoor unit 2 branches at a branch point, and each branch pipe is connected to the outdoor four-way switching valve 12A, 12B at the high pressure gas pipe port 12-1. The outdoor side four-way switching valve 12A, 12B is a low pressure that joins the low pressure gas pipe 4L at the branch point of the outdoor heat exchanger side port 12-2 connected to the outdoor heat exchangers 13A, 13B and the low pressure gas pipe 4L, respectively. A low pressure gas pipe side port 12-3 connected to the gas branch pipe and a bypass pipe side port 12-4 connected to the low pressure gas branch pipe via a strainer and a capillary tube are provided. The outdoor four-way switching valves 12A and 12B switch the connected outdoor heat exchanger 13 to the high pressure side or the low pressure side.

  The low pressure gas pipe 4 </ b> L located in the outdoor unit 2 is connected to the compressor 10 via an accumulator 19. The liquid refrigerant collected in the accumulator 19 is returned to the compressor 10 by a liquid refrigerant return line.

The refrigerant pipes 22 are connected to the outdoor heat exchangers 13A and 13B on the side opposite to the side connected to the outdoor four-way switching valves 12A and 12B. The refrigerant piping 22 in the outdoor unit 2 includes a receiver 16 for storing liquid refrigerant, and a supercooling heat exchanger 17 for supercooling the refrigerant flowing through the refrigerant piping 22 when the outdoor heat exchanger 13 operates as a condenser. Prepare. The subcooling heat exchanger 17 takes out part of the liquid refrigerant flowing through the refrigerant pipe 22, and subcools the liquid refrigerant flowing through the refrigerant pipe 22 by the refrigerant cooled and expanded and vaporized by the subcooling expansion valve (EEVSC) 18 Is supposed to give. The gas refrigerant used for subcooling and vaporized is returned to the accumulator 19.
The above-described devices on the outdoor unit 2 side are sequentially connected via the refrigerant pipe 22 to constitute a known outdoor-side refrigerant circuit 23. Further, the outdoor unit 2 is provided with an outdoor fan (not shown) for blowing the outside air to the outdoor heat exchanger 13.

  The low pressure gas pipe 4L, the high pressure gas pipe 4H, and the liquid side pipe 5 are refrigerant pipes connected to the gas side operation valve 20 and the liquid side operation valve 21 of the outdoor unit 2, and at the time of installation and construction at the site The pipe length is appropriately set in accordance with the distance between the plurality of indoor units 3A, 3B, 3C, 3D and 3E connected thereto. A branch (not shown) is provided in the middle of the low pressure gas pipe 4L, the high pressure gas pipe 4H and the liquid side pipe 5, and an appropriate number of indoor units 3A, 3B, 3C, 3D and 3E are provided via the branch. Is connected. Thus, a known closed refrigeration cycle (refrigerant circuit) 7 is configured.

  A plurality of indoor units 3 are provided, and the configuration of each indoor unit is the same. The indoor unit 3 includes an indoor heat exchanger 30 that exchanges heat with indoor air. An indoor electronic expansion valve 31 is provided in the liquid refrigerant branch pipe connecting the indoor heat exchanger 30 and the liquid side pipe 5. Each indoor unit 3 is provided with a diversion controller 8 that switches between the high pressure gas pipe 4H and the low pressure gas pipe 4L.

  The diversion controller 8 includes an indoor side four-way switching valve 81. The indoor side four-way switching valve 81 has a high pressure gas pipe port 81-1 connected to the high pressure gas branch pipe branched from the main pipe of the high pressure gas pipe 4H and an indoor heat exchanger side connected to the indoor heat exchanger 30 side. A low pressure gas pipe port 81-3 connected to the port 81-2 and the indoor low pressure gas branch pipe branched from the main pipe of the low pressure gas pipe 4L, and a low pressure bypass pipe joined to an intermediate position of the indoor low pressure gas branch pipe And a low pressure bypass pipe port 81-4 connected to the

During the heating operation, the indoor side four-way switching valve 81 communicates the high pressure gas pipe port 81-1 with the indoor heat exchanger side port 81-2, and the low pressure gas pipe port 81-3 and the low pressure bypass pipe port 81- 4 and in communication. Thus, high pressure gas is supplied to the indoor heat exchanger 30 during heating operation.
Further, the indoor side four-way switching valve 81 communicates the high pressure gas pipe port 81-1 with the low pressure bypass pipe port 81-4 during cooling operation, and the indoor heat exchanger side port 81-2 and the low pressure gas pipe port It communicates with 81-3. Thus, low pressure gas is supplied to the indoor heat exchanger 30 during cooling operation.

The high pressure gas branch pipe on the upstream side of the indoor side four-way switching valve 81 is provided with a high pressure gas branch pipe on-off valve. A bypass channel for high pressure gas branch pipe is formed to bypass the on-off valve for high pressure gas branch pipe, and a first capillary tube is provided in the bypass channel for high pressure gas branch pipe.
A second capillary tube is provided in the low pressure bypass pipe on the downstream side of the indoor side four-way switching valve 81.
A high pressure / low pressure bypass pipe (a bypass pipe) is provided between the high pressure gas branch pipe on the upstream side of the high pressure gas branch pipe bypass channel and the indoor side low pressure gas branch pipe on the downstream side (downstream of the middle position) of the low pressure bypass pipe. Is provided. In the high and low pressure bypass pipe, a high and low pressure bypass pipe on-off valve and a third capillary tube are sequentially provided from the high pressure gas branch pipe side toward the indoor low pressure gas branch pipe side.

The control device 70 acquires the set temperature set by the indoor controller or the like, the indoor temperature, the refrigerant temperature by the outlet temperature sensor 61 described later of each indoor heat exchanger 30, and the like, and opens each outdoor electronic expansion valve 15. Control of the degree, switching control of the outdoor side four-way switching valve 12, etc. are performed.
The control device 70 is configured of, for example, a central processing unit (CPU), a random access memory (RAM), a read only memory (ROM), a computer readable storage medium, and the like. Then, a series of processes for realizing various functions are stored in the form of a program, for example, in a storage medium or the like in the form of a program, and the CPU reads this program into a RAM or the like to execute information processing and arithmetic processing. Thus, various functions are realized. The program may be installed in advance in a ROM or other storage medium, may be provided as stored in a computer-readable storage medium, or may be distributed via a wired or wireless communication means. Etc. may be applied. The computer readable storage medium is a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory or the like.

The control device 70 includes a detection unit 71 and a control unit 72.
The detection unit 71 detects excess or deficiency of the amount of refrigerant based on the value acquired by the control device 70.
The control unit 72 controls each device of the multi-type air conditioner 1 in order to set the amount of refrigerant to an appropriate amount based on the excess / deficiency information of the amount of refrigerant detected by the detection unit 71.

FIG. 2 is a flowchart showing control at the time of refrigerant amount fluctuation of the multi-type air conditioning apparatus according to the present embodiment.
In the multi-type air conditioner 1, the required amount of refrigerant fluctuates due to various factors such as the air conditions and the number of indoor units operated. Therefore, it is detected whether the amount of refrigerant is excessive or insufficient, and control is performed so that an appropriate amount of refrigerant flows according to the fluctuation of the required amount of refrigerant.

<When the outdoor unit heat exchanger is an evaporator>
In the present embodiment, it is assumed that the outdoor heat exchanger 13A is stopped and the outdoor heat exchanger 13B is operating.
When the outdoor heat exchanger 13 is an evaporator, the outdoor four-way switching valve 12A corresponding to the stopped outdoor heat exchanger 13A and the outdoor four-way switching valve 12B corresponding to the operating outdoor heat exchanger 13B are The high pressure gas pipe port 12-1 communicates with the bypass pipe port 12-4, and the outdoor heat exchanger side port 12-2 communicates with the low pressure gas pipe port 12-3. The outdoor electronic expansion valve 15A corresponding to the outdoor heat exchanger 13A is closed. As a result, the refrigerant flowing from the high pressure gas pipe port 12-1 of the outdoor four-way selector valve 12A flows to the accumulator 19 through the bypass pipe port 12-4 and the outdoor heat exchanger is closed by closing the outdoor electronic expansion valve 15A. The refrigerant does not flow to 13A.

  First, as shown in step S201 of FIG. 2, the detection unit 71 determines whether the amount of the circulating refrigerant tends to be excessive. Whether the refrigerant amount is excessive or not is determined by the temperature difference between the temperature at the outlet of the indoor heat exchanger 30 of the indoor unit 3 and the temperature at the center.

FIG. 3 is a schematic view of the indoor heat exchanger of the multi-type air conditioner according to the present embodiment.
As shown in FIG. 3, in the indoor heat exchanger 30 of the indoor unit 3 performing the heating operation, the refrigerant flows in the direction of the arrow in the figure when the outdoor heat exchanger 13 operates as an evaporator. In the indoor heat exchanger 30 of the indoor unit 3, an outlet temperature sensor 61, a central temperature sensor 62, and an inlet temperature sensor 63 are provided sequentially from the refrigerant outlet side when the outdoor heat exchanger 13 operates as an evaporator. It is done. The outlet temperature sensor 61 measures an outlet temperature T1, the central temperature sensor 62 measures a central temperature T2, and the inlet temperature sensor 63 measures an inlet temperature T3.
When the refrigerant is flowing in an appropriate amount, the high temperature / high pressure refrigerant gas entered from the inlet (the inlet temperature sensor 63 side) of the indoor heat exchanger 30 is condensed and liquefied by heat exchange with the indoor air. Therefore, each temperature is T1 <T2 <T3.
On the other hand, when the amount of refrigerant is excessive, the receiver 16 overflows, the refrigerant is stored in the indoor heat exchanger 30 of the indoor unit 3, and the difference between the outlet temperature T1 and the central temperature T2 becomes substantially the same. The temperature is T1 ≒ T2 <T3. Therefore, when the temperature difference | T1-T2 | between the outlet temperature T1 and the central temperature T2 becomes equal to or less than the first temperature difference, the detection unit 71 detects that the refrigerant tends to be excessive. Here, the first temperature difference is, for example, 5 degrees.

  That is, at step S201 in FIG. 2, control device 70 determines whether the temperature difference | T1-T2 | between the outlet temperature T1 of the indoor heat exchanger 30 of the indoor unit 3 and the central portion temperature T2 is less than the first temperature difference. If the temperature difference is less than the first temperature difference, the process proceeds to step S202. On the other hand, if the difference is larger than the first temperature difference, the determination in step S201 is performed again.

When it is detected in step S201 that the temperature difference | T1-T2 | between the outlet temperature T1 of the indoor heat exchanger 30 of the indoor unit 3 and the central temperature T2 is equal to or less than the first temperature difference, that is, the refrigerant amount is excessive The control unit 72 performs control to switch the outdoor four-way switching valve 12A of the stopped outdoor heat exchanger 13A (S202).
The switched outdoor four-way selector valve 12A communicates the high pressure gas pipe port 12-1 with the outdoor heat exchanger side port 12-2, and the low pressure gas pipe side port 12-3 and the bypass pipe side port 12-. 4 and in communication. Thus, the refrigerant discharged from the compressor 10 flows to the outdoor heat exchanger 13A through the high pressure gas pipe port 12-1 and the outdoor heat exchanger side port 12-2 of the outdoor four-way selector valve 12A. At this time, since the outdoor electronic expansion valve 15A is closed, the refrigerant is stored in the outdoor heat exchanger 13A. Thus, the refrigerant which has tended to be excessive is collected by the outdoor heat exchanger 13A.

Next, in step S203, the detection unit 71 determines whether the amount of flowing refrigerant tends to be insufficient or excessive. It is judged by the opening degree of the expansion valve of the evaporator whether or not the refrigerant amount is insufficient.
In general, when the appropriate amount of refrigerant is supplied to the indoor unit 3, the outdoor electronic expansion valve 15B corresponding to the electronic expansion valve of the evaporator, that is, the outdoor heat exchanger 13B in which the outdoor unit 2 is operating The indoor electronic expansion valve 31 corresponding to the indoor unit 3 is set to a predetermined opening (for example, 100 to 200 pulses). However, if the amount of refrigerant in the indoor unit 3 is insufficient, it is necessary to circulate the refrigerant more, so the degree of opening of the indoor electronic expansion valve 31 corresponding to the outdoor electronic expansion valve 15B of the outdoor unit 2 or the indoor unit 3 in the cooling operation. Is equal to or greater than the predetermined opening. Here, the predetermined opening degree is, for example, the maximum opening degree of the outdoor electronic expansion valve 15B or the indoor electronic expansion valve 31. Therefore, the shortage tendency of the refrigerant amount can be detected by the opening degree of the outdoor electronic expansion valve 15B or the indoor electronic expansion valve 31 corresponding to the indoor unit 3 in the cooling operation.

In step S203, control device 70 determines whether the opening degree of outdoor electronic expansion valve 15B of outdoor heat exchanger 13B of outdoor unit 2 or indoor electronic expansion valve 31 corresponding to indoor unit 3 in the cooling operation is the maximum opening degree. If it is determined that the opening degree is maximum, that is, if it is determined that the refrigerant amount is insufficient, the process proceeds to step S204.
Further, as in step S201, the control device 70 determines whether the amount of refrigerant is excessive. If it is determined that the refrigerant amount is excessive, the process proceeds to step S204.
On the other hand, if it is determined that the amount of the circulating refrigerant is neither the shortage tendency nor the excess tendency, the process proceeds to step S206.

In step S203, the opening degree of the indoor electronic expansion valve 31 corresponding to the outdoor electronic expansion valve 15B of the outdoor heat exchanger 13B of the outdoor unit 2 or the indoor unit 3 in the cooling operation is the maximum opening degree When it is detected that the quantity is insufficient, the control unit 72 causes the outdoor electronic exchanger 13 (in the case of this embodiment, the outdoor heat exchanger 13A in the present embodiment) to be fully closed. The opening degree of the expansion valve 15A is adjusted in the opening direction, for example, slightly opened (S204).
Since the outdoor electronic expansion valve 15A of the outdoor heat exchanger 13A which has been stopped is fully closed and the refrigerant is stored in the outdoor heat exchanger 13A, the amount of refrigerant which has tended to be excessive decreases. Here, when the amount of refrigerant in the indoor unit 3 runs short and the capacity decrease is detected by the detection unit 71, the control unit 72 opens the outdoor electronic expansion valve 15A of one of the stopped outdoor heat exchangers 13A. Adjustment, for example, control to make it slightly open, and recover the refrigerant stored in the outdoor heat exchanger 13A.

FIG. 4 is a graph showing the relationship between the opening degree of the indoor electronic expansion valve of the multi-type air conditioner according to the present embodiment and the flow rate.
In FIG. 4, the vertical axis is the flow rate, and the horizontal axis is the expansion valve opening degree.
Here, slightly open indicates an opening degree that is larger than the opening degree at which the refrigerant is stored in the outdoor heat exchanger 13 and is sufficiently smaller than the maximum opening degree of the valve.
Assuming that the maximum opening degree of the outdoor electronic expansion valve 15 of the present embodiment is D, the flow rate in that case is F from FIG. Further, assuming that the flow rate necessary for slightly opening the outdoor electronic expansion valve 15 is a, the expansion valve opening degree in that case is da from FIG.
For example, when the refrigerant flow rate when the outdoor electronic expansion valve 15 is at the maximum opening degree is 50 kg / h, the opening degree when the outdoor electronic expansion valve 15A of the outdoor heat exchanger 13A that is stopped is slightly opened The opening degree may be such that the flow rate of the refrigerant is 10 kg / h.

In step S203, when the detection unit 71 detects that the refrigerant amount is excessive, the control unit 72 stops the operation of the outdoor heat exchanger 13 (in the case of the present embodiment, the outdoor heat exchanger 13A). The opening degree of the open outdoor electronic expansion valve 15A is adjusted in the closing direction (S204). Adjusting the opening degree of the outdoor electronic expansion valve 15A in the closing direction means, for example, performing control such as making the opening degree several pulses smaller than the opening degree of the current outdoor electronic expansion valve 15A.
By adjusting the opening degree of the outdoor electronic expansion valve 15A of the outdoor heat exchanger 13A stopped due to the insufficient amount of refrigerant in the opening direction and recovering the refrigerant from the outdoor heat exchanger 13A, the amount of refrigerant which has tended to be insufficient increases Do. Here, when the amount of refrigerant in the indoor unit 3 becomes excessive and the capacity decrease is detected by the detection unit 71, the control unit 72 controls the adjustment of the outdoor electronic expansion valve 15A of the stopped outdoor heat exchanger 13A in the closing direction. The amount of refrigerant to be collected is reduced, or the refrigerant is stored in the outdoor heat exchanger 13A.

  Next, in step S205, the detection unit 71 determines whether the operation is stable. Specifically, it is determined that the amount of refrigerant does not tend to be excessive and the amount of refrigerant does not tend to be insufficient, and it is determined that the operation is stable if none of the above apply. If the detection unit 71 determines that the driving is stable, the process proceeds to step S206. On the other hand, when it is determined that the driving is not stable, the process returns to step S203.

  If it is determined in step S205 that the operation is stable, or if it is determined in step S203 that the refrigerant lack tendency and the refrigerant excess tendency are not present, the operation is continued (S206). Thereafter, the control shown in this flowchart is repeated.

<When the outdoor heat exchanger is a condenser>
In the present embodiment, it is assumed that the outdoor heat exchanger 13A is stopped and the outdoor heat exchanger 13B is operating.
When the outdoor heat exchanger 13 is a condenser, the outdoor four-way switching valve 12A corresponding to the stopped outdoor heat exchanger 13A communicates the high pressure gas pipe port 12-1 with the bypass pipe side port 12-4. And the outdoor heat exchanger side port 12-2 and the low pressure gas pipe side port 12-3 are communicated with each other. The outdoor electronic expansion valve 15A corresponding to the outdoor heat exchanger 13A is closed. As a result, the refrigerant flowing from the high pressure gas pipe port 12-1 of the outdoor four-way selector valve 12A flows to the accumulator 19 through the bypass pipe side port 12-4, so the refrigerant does not flow to the outdoor heat exchanger 13A. .
On the other hand, the outdoor four-way selector valve 12B corresponding to the outdoor heat exchanger 13B in operation communicates the high pressure gas pipe port 12-1 with the outdoor heat exchanger side port 12-2, and on the low pressure gas pipe side. The port 12-3 communicates with the bypass pipe side port 12-4.

  First, as shown in step S201 of FIG. 2, the detection unit 71 determines whether the amount of the circulating refrigerant tends to be excessive. Whether the refrigerant amount is excessive or not is determined by the temperature difference between the temperature at the outlet of the indoor heat exchanger 30 of the indoor unit 3 and the temperature at the center.

FIG. 3 is a schematic view of the indoor heat exchanger of the multi-type air conditioner according to the present embodiment.
As shown in FIG. 3, in the indoor heat exchanger 30 of the indoor unit 3 performing the heating operation, the refrigerant flows in the direction of the arrow in FIG. 3 when the outdoor heat exchanger 13 operates as a condenser. . In the indoor heat exchanger 30 of the indoor unit 3, an outlet temperature sensor 61, a central temperature sensor 62, and an inlet temperature sensor 63 are provided sequentially from the refrigerant outlet side when the outdoor heat exchanger 13 operates as a condenser. It is done. The outlet temperature sensor 61 measures an outlet temperature T1, the central temperature sensor 62 measures a central temperature T2, and the inlet temperature sensor 63 measures an inlet temperature T3.
When the refrigerant is flowing in an appropriate amount, the high temperature / high pressure refrigerant gas entered from the inlet (the inlet temperature sensor 63 side) of the indoor heat exchanger 30 is condensed and liquefied by heat exchange with the indoor air. Therefore, each temperature is T1 <T2 <T3.
On the other hand, when the amount of refrigerant is excessive, the receiver 16 overflows, the refrigerant is stored in the indoor heat exchanger 30 of the indoor unit 3, and the difference between the outlet temperature T1 and the central temperature T2 becomes substantially the same. The temperature is T1 ≒ T2 <T3. Therefore, when the temperature difference | T1-T2 | between the outlet temperature T1 and the central temperature T2 becomes equal to or less than the first temperature difference, the detection unit 71 detects that the refrigerant tends to be excessive. Here, the first temperature difference is, for example, 5 degrees.

  That is, at step S201 in FIG. 2, control device 70 determines whether the temperature difference | T1-T2 | between the outlet temperature T1 of the indoor heat exchanger 30 of the indoor unit 3 and the central portion temperature T2 is less than the first temperature difference. If the temperature difference is less than the first temperature difference, the process proceeds to step S202. On the other hand, if the difference is larger than the first temperature difference, the determination in step S201 is performed again.

When it is detected in step S201 that the temperature difference | T1-T2 | between the outlet temperature T1 of the indoor heat exchanger 30 of the indoor unit 3 and the central temperature T2 is equal to or less than the first temperature difference, that is, the refrigerant amount is excessive The control unit 72 performs control to switch the outdoor four-way switching valve 12A of the stopped outdoor heat exchanger 13A (S202).
The switched outdoor four-way selector valve 12A communicates the high pressure gas pipe port 12-1 with the outdoor heat exchanger side port 12-2, and the low pressure gas pipe side port 12-3 and the bypass pipe side port 12-. 4 and in communication. Thus, the refrigerant discharged from the compressor 10 flows to the outdoor heat exchanger 13A through the high pressure gas pipe port 12-1 and the outdoor heat exchanger side port 12-2 of the outdoor four-way selector valve 12A. At this time, since the outdoor electronic expansion valve 15A is closed, the refrigerant is stored in the outdoor heat exchanger 13A. Thus, the refrigerant which has tended to be excessive is collected by the outdoor heat exchanger 13A.

Next, in step S203, the detection unit 71 determines whether the amount of flowing refrigerant tends to be insufficient or excessive. Whether or not the amount of refrigerant is insufficient is determined by the opening degree of the expansion valve of the evaporator (in the case of the present embodiment, the indoor heat exchanger 30 of the indoor unit 3).
Normally, when the appropriate amount of refrigerant is supplied to the indoor unit 3, the electronic expansion valve of the evaporator, that is, the indoor electronic expansion valve 31 corresponding to the indoor heat exchanger 30 in operation of the indoor unit 3 is opened. (For example, 100 to 200 pulses). However, when the amount of refrigerant in the indoor unit 3 is insufficient, it is necessary to circulate the refrigerant more, so the opening degree of the indoor electronic expansion valve 31 of the indoor unit 3 becomes equal to or more than the predetermined opening degree. Here, the predetermined opening degree is, for example, the maximum opening degree of the indoor electronic expansion valve 31. Therefore, the shortage tendency of the refrigerant amount can be detected by the opening degree of the indoor electronic expansion valve 31.

In step S203, control device 70 determines whether the opening degree of indoor electronic expansion valve 31 corresponding to indoor heat exchanger 30 in operation of indoor unit 3 is the maximum opening degree, which is the maximum opening degree. In the case where it is determined that the refrigerant amount is insufficient, the process proceeds to step S204.
Further, as in step S201, the control device 70 determines whether the amount of refrigerant is excessive. If it is determined that the refrigerant amount is excessive, the process proceeds to step S204.
On the other hand, if it is determined that the amount of the circulating refrigerant is neither the shortage tendency nor the excess tendency, the process proceeds to step S206.

When the opening degree of the indoor electronic expansion valve 31 corresponding to the indoor heat exchanger 30 in operation of the indoor unit 3 is detected by the detection unit 71 in step S203 as the maximum opening degree, that is, the refrigerant amount is insufficient The control unit 72 causes the open degree of the outdoor electronic expansion valve 15A, which is fully closed in any one of the stopped outdoor heat exchangers 13 (in the case of this embodiment, the outdoor heat exchanger 13A), to open. Adjustment, for example, slight opening (S204).
Since the outdoor electronic expansion valve 15A of the outdoor heat exchanger 13A which has been stopped is fully closed and the refrigerant is stored in the outdoor heat exchanger 13A, the amount of refrigerant which has tended to be excessive decreases. Here, when the amount of refrigerant in the indoor unit 3 runs short and the capacity decrease is detected by the detection unit 71, the control unit 72 opens the outdoor electronic expansion valve 15A of one of the stopped outdoor heat exchangers 13A. Control is performed to adjust the amount of refrigerant, and the refrigerant stored in the outdoor heat exchanger 13A is recovered.

In step S203, when the detection unit 71 detects that the refrigerant amount is excessive, the control unit 72 stops the operation of the outdoor heat exchanger 13 (in the case of the present embodiment, the outdoor heat exchanger 13A). The opening degree of the open outdoor electronic expansion valve 15A is adjusted in the closing direction (S204). Adjusting the opening degree of the outdoor electronic expansion valve 15A in the closing direction means, for example, performing control such as making the opening degree several pulses smaller than the opening degree of the current outdoor electronic expansion valve 15A.
By adjusting the opening degree of the outdoor electronic expansion valve 15A of the outdoor heat exchanger 13A stopped due to the insufficient amount of refrigerant in the opening direction and recovering the refrigerant from the outdoor heat exchanger 13A, the amount of refrigerant which has tended to be insufficient increases Do. Here, when the amount of refrigerant in the indoor unit 3 becomes excessive and the capacity decrease is detected by the detection unit 71, the control unit 72 controls the adjustment of the outdoor electronic expansion valve 15A of the stopped outdoor heat exchanger 13A in the closing direction. The amount of refrigerant to be collected is reduced, or the refrigerant is stored in the outdoor heat exchanger 13A.

  Next, in step S205, the detection unit 71 determines whether the operation is stable. Specifically, it is determined that the amount of refrigerant does not tend to be excessive and that the amount of refrigerant does not tend to be insufficient, and it is determined that the operation is stable when neither of the refrigerant amount is excessive nor the refrigerant amount is insufficient. . If the detection unit 71 determines that the driving is stable, the process proceeds to step S206. On the other hand, when it is determined that the driving is not stable, the process returns to step S203.

  If it is determined in step S205 that the operation is stable, or if it is determined in step S203 that the refrigerant lack tendency and the refrigerant excess tendency are not present, the operation is continued (S206). Thereafter, the control shown in this flowchart is repeated.

As described above, when the amount of refrigerant is excessive, the outdoor four-way switching valve 12 corresponding to the stopped outdoor heat exchanger 13 is switched, and when the amount of refrigerant is insufficient, any one outdoor heat exchange is stopped. Control is performed to adjust the outdoor electronic expansion valve 15 corresponding to the controller 13 in the opening direction.
By setting the outdoor side four-way switching valve 12 so that the required amount of refrigerant can be circulated by performing the correction by the control from step S203 to step S205 so as not to repeat these controls frequently, the outdoor electronic expansion valve 15 The open / close state of is determined.

Further, in the present embodiment, in step S201 of FIG. 2, the excess refrigerant amount is detected based on the temperature difference. However, conditions may be added.
For example, the state where the difference between the set temperature of the indoor unit 3 and the indoor temperature is the second temperature difference or more continues for a predetermined time or longer, and the outlet temperature T1 of the indoor heat exchanger 30 provided in the indoor unit 3 and the center When the difference with the part temperature T2 is equal to or less than the first temperature difference, the indoor unit 3 may detect that the refrigerant amount is excessive.
The state where the difference between the set temperature of the indoor unit 3 and the room temperature is equal to or greater than the second temperature difference means that the difference between the set temperature set by the user using the indoor controller or the like and the actual room temperature is large. Do. If this continues for a predetermined time or more, it can be said that the multi-type air conditioner 1 is not warm in the case of heating, and is not cool in the case of cooling. Therefore, it may be detected that the amount of refrigerant in the indoor unit 3 is excessive because the indoor unit 3 is in the unheated or uncooled state and the refrigerant amount is excessive. This makes it possible to prevent unnecessary control without frequent setting changes. Here, the second temperature difference is, for example, 3 degrees, and the predetermined time is, for example, 5 minutes.

As described above, according to the control device of the multi-type air conditioner according to this embodiment, the multi-type air conditioner, the control method of the multi-type air conditioner, and the control program of the multi-type air conditioner, The effects of
According to the present embodiment, at least one outdoor unit 2 having a plurality of circuits composed of the outdoor four-way switching valve 12, the outdoor heat exchanger 13, and the outdoor electronic expansion valve 15, and a plurality of indoor units 3 The control device 70 of the multi-type air conditioner 1 provided, which is provided in the indoor unit 3 when the outdoor electronic expansion valve 15 of at least one circuit is fully closed and the outdoor heat exchanger 13 is in the stop state. When it is detected that the difference between the outlet temperature T1 of the indoor heat exchanger 30 and the central temperature T2 is less than or equal to the first temperature difference and the refrigerant amount is excessive, a chamber corresponding to the outdoor heat exchanger 13 in the stopped state Since the control for switching the outer four-way switching valve 12 is performed, the amount of refrigerant in the indoor unit 3 becomes excessive and a decrease in capacity is detected, the outer four-way switching valve 12 corresponding to the outdoor heat exchanger 13 in the stopped state is switched Being stopped Refrigerant is stored in the outdoor heat exchanger 13 that.
When the required capacity for the outdoor unit 2 is not large and the required capacity can be satisfied by the operation of only a part of the outdoor heat exchangers 13, the other outdoor heat exchangers 13 can be stopped. In that case, the outdoor heat exchanger 13 is fully closed when the corresponding outdoor electronic expansion valve 15 is fully closed, and additionally when the outdoor heat exchanger 13 is a condenser, the outdoor four-way switching valve 12 is switched. Stopped.
When the circulating refrigerant tends to be excessive, the refrigerant is stored in the receiver 16 of the outdoor unit 2. However, when the refrigerant exceeds the stored amount of the receiver 16 and is further excessive, the refrigerant amount of the indoor unit 3 becomes excessive and the capacity decreases. . Whether or not the refrigerant amount is excessive can be detected when the difference between the outlet temperature T1 of the indoor heat exchanger 30 provided in the indoor unit 3 and the central portion temperature T2 becomes equal to or less than the first temperature difference. This is because the receiver 16 overflows and the refrigerant becomes excessive, the refrigerant is stored in the indoor heat exchanger 30 of the indoor unit 3, and the difference between the outlet temperature T1 and the central temperature T2 becomes substantially the same.
Although the outdoor heat exchanger 13 in the stopped state is stopped as described above, when the control device 70 detects an excessive amount of refrigerant, the control device 70 is in the four outdoor sides corresponding to the outdoor heat exchanger 13 in the stopped state. Control to switch the switching valve 12 is performed.
As a result, the refrigerant is stored in the outdoor heat exchanger 13 in the stopped state, and an appropriate amount of the refrigerant is supplied to the indoor unit 3, so that the capacity deterioration can be prevented. In addition, since the amount of refrigerant can be adjusted by controlling the outdoor four-way switching valve 12, it is not necessary to increase the capacity of the receiver 16 of the outdoor unit 2, leading to cost reduction. Further, in the installation of the multi-type air conditioner 1, the charge amount of the refrigerant is determined by the number of indoor units 3 and the length of the refrigerant pipe, but the amount of refrigerant can be adjusted by controlling the outdoor four-way switching valve 12 Even if the charge amount is set larger than the appropriate amount, it is acceptable.
In addition, since the indoor heat exchanger 30 is not used for storing the refrigerant, there is no influence on the indoor environment such as overheating.

Further, according to the present embodiment, when the outdoor heat exchanger 13 is a condenser when the refrigerant is stored in the outdoor heat exchanger 13 in at least one stopped state, the indoor electronic expansion valve 31 of the indoor unit 3 When the outdoor heat exchanger 13 is an evaporator, the opening degree of the outdoor electronic expansion valve 15 of the outdoor unit 2 is at least the second predetermined opening degree or the indoor unit 3 in the cooling operation. When it is detected that the opening degree of the indoor electronic expansion valve 31 corresponding to the first opening degree is greater than or equal to the first predetermined opening degree and the refrigerant amount is insufficient, closing corresponding to the outdoor heat exchanger 13 in which any one refrigerant is stored Since the control to adjust the outdoor electronic expansion valve 15 in the opening direction is performed, the refrigerant is stored in the outdoor heat exchanger 13 by switching of the outdoor four-way switching valve 12, and the amount of refrigerant in the indoor unit 3 runs short. If a decrease in capacity is detected, any one refrigerant Adjusting the outdoor electronic expansion valve 15 corresponding to the outdoor heat exchanger 13 that is stored in the opening direction, for example, performs control to BiHiraku, recovering the refrigerant stored in the outdoor heat exchanger 13. Thereby, the amount of refrigerant of the indoor unit 3 can be corrected. In addition, by repeating this correction, an appropriate amount of refrigerant is supplied to the indoor unit 3, and the operation of the multi-type air conditioner 1 can be stabilized.
In addition, although the outdoor heat exchanger 13 has a large capacity, it is easy to store the refrigerant, but it may be stored too much, but the control of adjusting in the opening direction can be performed to adjust the amount of refrigerant.
When the outdoor heat exchanger 13 is a condenser, the opening degree of the indoor electronic expansion valve 31 of the indoor unit 3 is equal to or more than the first predetermined opening, and when the outdoor heat exchanger 13 is an evaporator, the outdoor electrons of the outdoor unit 2 When the opening degree of the expansion valve 15 is the second predetermined opening degree or more, or the opening degree of the indoor electronic expansion valve 31 corresponding to the indoor unit 3 in the cooling operation becomes the first predetermined opening degree or more, the indoor unit 3 Since the shortage of the amount is detected, the shortage of the refrigerant amount of the indoor unit 3 can be detected by a simple method.
When the appropriate amount of refrigerant is supplied to the indoor unit 3, the electronic expansion valve of the evaporator, that is, when the outdoor heat exchanger 13 is a condenser, the indoor electronic expansion valve 31 of the indoor unit 3 and the outdoor heat exchanger 13 evaporate In this case, the opening degree of the outdoor electronic expansion valve 15 of the outdoor unit 2 or the opening degree of the indoor electronic expansion valve 31 corresponding to the indoor unit 3 in the cooling operation is a predetermined opening degree. If the amount of refrigerant in the indoor unit 3 is insufficient, it is necessary to circulate the refrigerant more, so when the outdoor heat exchanger 13 is a condenser, the indoor electronic expansion valve 31 of the indoor unit 3 and the outdoor heat exchanger 13 are evaporators. In this case, the opening degree of the outdoor electronic expansion valve 15 of the outdoor unit 2 or the opening degree of the indoor electronic expansion valve 31 corresponding to the indoor unit 3 in the cooling operation becomes equal to or more than the predetermined opening degree. Here, the first predetermined opening degree is, for example, the maximum opening degree of the indoor electronic expansion valve 31, and the second predetermined opening degree is, for example, the maximum opening degree of the outdoor electronic expansion valve 15.

  Further, according to the present embodiment, the indoor heat provided to the indoor unit 3 when the outdoor electronic expansion valve 15 corresponding to the outdoor heat exchanger 13 in at least one stopped state and in which the refrigerant is stored is open. When it is detected that the difference between the outlet temperature T1 of the exchanger 30 and the central temperature T2 is equal to or less than the first temperature difference and the refrigerant amount is excessive, the outdoor electronic expansion valve 15 corresponding to the outdoor heat exchanger 13 is closed. Control to adjust in the direction. Since the refrigerant is stored in the outdoor heat exchanger 13 by switching the outdoor four-way switching valve 12, the amount of refrigerant in the indoor unit 3 runs short and the outdoor electronic expansion valve 15 is opened. However, the amount of collected refrigerant is large. Then, control is performed to adjust the outdoor electronic expansion valve 15 corresponding to the corresponding outdoor heat exchanger 13 in the closing direction, and the amount of refrigerant to be collected is reduced, or the refrigerant is stored in the outdoor heat exchanger 13. Thereby, the amount of refrigerant of the indoor unit 3 can be corrected. In addition, by repeating this correction, an appropriate amount of refrigerant is supplied to the indoor unit 3, and the operation of the multi-type air conditioner 1 can be stabilized.

  Further, according to the present embodiment, the state in which the difference between the set temperature of one or more indoor units 3 and the indoor temperature is the second temperature difference or more continues for a predetermined time or more, and is provided in the indoor unit 3. When the difference between the outlet temperature T1 of the indoor heat exchanger 30 and the central temperature T2 is equal to or less than the first temperature difference, it is detected that the indoor unit 3 has an excessive amount of refrigerant. The state where the difference between the set temperature of the indoor unit 3 and the room temperature is equal to or greater than the second temperature difference means that the difference between the set temperature set by the user using the indoor controller or the like and the actual room temperature is large. Do. If this continues for a predetermined time or more, it can be said that the multi-type air conditioner 1 is not warm in the case of heating, and is not cool in the case of cooling. Further, if the difference between the outlet temperature T1 of the indoor heat exchanger 30 and the central temperature T2 of the indoor unit 3 is equal to or less than the first temperature difference, the receiver 16 overflows and the refrigerant becomes excessive and the indoor unit 3 This means that the refrigerant is stored in the indoor heat exchanger 30 and the difference between the outlet temperature T1 and the central portion temperature T2 is substantially the same. Therefore, it is detected that the amount of refrigerant in the indoor unit 3 is excessive, as the indoor unit 3 is in the unheated or uncooled state and the refrigerant amount is excessive. This makes it possible to prevent unnecessary control without frequent setting changes.

DESCRIPTION OF SYMBOLS 1 multi-type air conditioner 2 outdoor unit 3 indoor unit 8 diversion controller 10 compressor 12 outdoor four-way switching valve 13 outdoor heat exchanger 15 outdoor electronic expansion valve 16 receiver 30 indoor heat exchanger 31 indoor electronic expansion valve 70 control device 71 Detection unit 72 Control unit

Claims (7)

At least one outdoor unit having a plurality of circuits composed of a four-way switching valve, an outdoor heat exchanger, and an outdoor electronic expansion valve;
With multiple indoor units,
Control device for a multi-type air conditioner provided with
When the outdoor electronic expansion valve of at least one of the circuits is fully closed and the outdoor heat exchanger is in the stop state, the difference between the outlet temperature of the indoor heat exchanger provided in the indoor unit and the central portion temperature The controller of the multi-type air conditioner performs control of switching the four-way switching valve corresponding to the outdoor heat exchanger in the stopped state when it is detected that the first temperature difference is less than or equal to the first temperature difference. The indoor units each have an indoor electronic expansion valve,
When refrigerant is stored in the outdoor heat exchanger in at least one stopped state, the opening degree of the indoor electronic expansion valve of the indoor unit is a first predetermined value when the outdoor heat exchanger is a condenser. The opening degree of the outdoor electronic expansion valve of the outdoor unit is equal to or higher than the second predetermined opening degree or the indoor electronic expansion valve of the indoor unit during the cooling operation when the outdoor heat exchanger is the evaporator. When it is detected that the opening degree is equal to or more than the first predetermined opening degree and the refrigerant amount is insufficient, the closed state corresponding to the outdoor heat exchanger in any one of the stopped states and in which the refrigerant is stored The control device for a multi-type air conditioner according to claim 1, wherein control is performed to adjust the outdoor electronic expansion valve in the opening direction.   The outlet temperature and the central portion of the indoor heat exchanger provided in the indoor unit when the outdoor electronic expansion valve corresponding to the outdoor heat exchanger which is in at least one stopped state and in which the refrigerant is stored is open When the difference with the temperature is equal to or less than the first temperature difference and it is detected that the refrigerant amount is excessive, control is performed to adjust the outdoor electronic expansion valve corresponding to the outdoor heat exchanger in the closing direction. Control device of multi-type air conditioner.   The state in which the difference between the set temperature of one or more indoor units and the indoor temperature is equal to or greater than the second temperature difference continues for a predetermined time or longer, and the outlet temperature and the center of the indoor heat exchanger provided in the indoor unit The control device for a multi-type air conditioner according to any one of claims 1 to 3, wherein the indoor unit detects that the amount of refrigerant is excessive when the difference from the unit temperature is equal to or less than the first temperature difference. . The control device according to any one of claims 1 to 4.
At least one outdoor unit having a plurality of circuits composed of a four-way switching valve, an outdoor heat exchanger, and an outdoor electronic expansion valve;
With multiple indoor units,
Multi-type air conditioner with. At least one outdoor unit having a plurality of circuits composed of a four-way switching valve, an outdoor heat exchanger, and an outdoor electronic expansion valve;
With multiple indoor units,
A control method of a multi-type air conditioner provided with
When the outdoor electronic expansion valve of at least one of the circuits is fully closed and the outdoor heat exchanger is in the stop state, the difference between the outlet temperature of the indoor heat exchanger provided in the indoor unit and the central portion temperature A method of controlling a multi-type air conditioner, comprising the step of switching the four-way switching valve corresponding to the outdoor heat exchanger in the stopped state when it is detected that the first temperature difference is less than or equal to the first temperature difference. At least one outdoor unit having a plurality of circuits composed of a four-way switching valve, an outdoor heat exchanger, and an outdoor electronic expansion valve;
With multiple indoor units,
And a control program for a multi-type air conditioner provided with
When the outdoor electronic expansion valve of at least one of the circuits is fully closed and the outdoor heat exchanger is in the stop state, the difference between the outlet temperature of the indoor heat exchanger provided in the indoor unit and the central portion temperature The control program of the multi-type air conditioner having the step of switching the four-way switching valve corresponding to the outdoor heat exchanger in the stopped state when it is detected that the first temperature difference is less than or equal to the refrigerant amount.

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