JP5916488B2 - Control apparatus and method, program, and multi-type air conditioning system including the same - Google Patents

Description

  The present invention relates to a control apparatus and method, a program, and a multi-type air conditioning system including the same.

A multi-type air conditioning system used for air conditioning of a building or the like is configured such that a plurality of indoor units are connected to one outdoor unit. In such a multi-type air conditioning system, start / stop of operation is controlled for each indoor unit, and thermo-on / off is controlled depending on whether the room temperature reaches the set temperature range.
In the heating operation, when the indoor temperature reaches the set temperature range and the thermostat is turned off, the heating capacity is unnecessary in the indoor unit, but other indoor units connected to the common outdoor unit are operating Since the compressor of the outdoor unit continues to operate, the system is in a state where the refrigerant continuously flows. Therefore, for indoor units that have been thermo-off or that have been shut down, do not close the indoor unit expansion valve, leave them slightly open to allow the refrigerant to flow, and prevent the refrigerant from accumulating. Yes.

In addition, in an indoor unit that is in the thermo-off state of the heating operation, the temperature sensor on the indoor unit side warms up the air in the indoor unit even though the indoor temperature is outside the set temperature range and the thermo-on should be resumed. As a result, it is assumed that the thermo-on cannot be performed properly. In order to avoid such a situation, conventionally, even in a thermo-off state, an operation in which an indoor unit fan is appropriately turned on / off to detect the room temperature is performed.
For example, in Patent Document 1 below, the number of indoor unit fans that are driven at the same time among a plurality of indoor units that are in a thermo-off state is limited, and the fan drive timing is shifted, so that the temperature of the blowout temperature from the indoor unit is abrupt. A technique for suppressing such a decrease is disclosed.

Japanese Patent No. 3778117

  By the way, in Patent Document 1, it is inevitable that the refrigerant in the indoor unit is condensed by operating the fan of the indoor unit during the thermo-off, and the amount of refrigerant necessary for the system is increased. Also, in order to remove the refrigerant accumulated in the indoor unit, it is necessary to open the indoor unit expansion valve. However, if it is opened more than necessary, the heating function is not required because the thermo-off is in progress. There is a problem that the capacity is increased and the system is overheated or the problem of noise occurs.

  The present invention has been made in view of such circumstances, and a control device, method, and program for intermittently operating a fan of a thermo-off indoor unit while preventing overheating while preventing overheating. It aims at providing the multi type air harmony system provided with.

In order to solve the above problems, the present invention employs the following means.
The present invention controls the operation of a multi-type air conditioning system in which a plurality of indoor units are connected to an outdoor unit, and the flow rate of refrigerant flowing through the refrigerant pipe is adjusted by the opening of the electric expansion valve of the indoor unit When the indoor fan of the indoor unit that circulates indoor air rotates for a predetermined time and performs an on-off operation that stops for a predetermined time when the thermo-off during heating is performed, during the off period of the indoor fan Provides a control device that controls the electric expansion valve of the indoor unit to an opening that is larger than the opening of the indoor fan during the ON period and less than or equal to the opening of noise countermeasures.

  According to such a configuration, the operation of the multi-type air conditioning system in which a plurality of indoor units are connected to the outdoor unit, and the flow rate of refrigerant flowing through the refrigerant pipe is adjusted by the opening degree of the electric expansion valve of the indoor unit. When the indoor fan of the indoor unit that circulates the indoor air rotates for a predetermined time and performs an on / off operation in which the operation is stopped for a predetermined time at the time of the thermo-off during heating, the indoor fan is turned off. The opening degree of the electric expansion valve of the indoor unit is controlled to be larger than the opening degree of the indoor fan during the ON period and not more than the opening degree for noise countermeasures.

  Thus, since the opening degree of the electric expansion valve is widened when the indoor fan is in the off period (that is, the indoor fan does not rotate) than during the indoor fan is on, the opening degree is increased during the on period of the indoor fan. Compared with the case of widening, it is possible to prevent overheating. In addition, since the electric expansion valve has an opening larger than the opening during the on-period of the indoor fan, the refrigerant can be extracted from the indoor unit in the thermo-off state, and the gas low state of the system can be prevented. Furthermore, since the opening is reduced to an opening equal to or less than the opening at which noise is generated by making the opening less than the noise countermeasure opening, noise can be suppressed and sound complaints from the surroundings can be prevented.

  In the above control device, the opening degree of the electric expansion valve during the on-period of the indoor fan is such that a minute amount of refrigerant flows so that the refrigerant naturally condensed in the heat exchanger of the indoor unit does not accumulate. When it is opened, it is preferable that the opening degree of the electric expansion valve during the off-period of the indoor fan is an opening degree in a range of 1.1 to 2.5 times with respect to the slight opening.

  Thereby, since it prevents that an electric expansion valve opens too much, overheating can be prevented reliably and a sound claim can also be suppressed.

The said control apparatus WHEREIN: The opening degree of the said electric expansion valve of the said indoor unit is good also as being controlled in the partial period in the OFF period of the said indoor fan.
During the off-period of the indoor fan, the refrigerant accumulated in the indoor unit can be removed.

  The present invention controls the operation of a multi-type air conditioning system in which a plurality of indoor units are connected to an outdoor unit, and the flow rate of refrigerant flowing through the refrigerant pipe is adjusted by the opening of the electric expansion valve of the indoor unit When the indoor fan of the indoor unit that circulates indoor air rotates for a predetermined time and performs an on / off operation in which the operation is stopped for a predetermined time when the thermo-off during heating is performed, Provides a control method for controlling the electric expansion valve of the indoor unit to an opening larger than the opening of the indoor fan during the ON period and not more than the opening for noise countermeasures.

  The present invention controls the operation of a multi-type air conditioning system in which a plurality of indoor units are connected to an outdoor unit, and the flow rate of refrigerant flowing through the refrigerant pipe is adjusted by the opening of the electric expansion valve of the indoor unit When the indoor fan of the indoor unit that circulates the indoor air rotates for a predetermined time and repeats an on / off operation that stops for a predetermined time when the thermo is turned off during heating. Is a control program for causing a computer to control the electric expansion valve of the indoor unit to an opening larger than an opening of the indoor fan during an on period and not more than an opening for noise countermeasures. I will provide a.

  The present invention has an effect that an indoor fan in a thermo-off state can be intermittently operated while preventing overheating while preventing overheating.

It is the figure which showed schematic structure of the refrigerant circuit of the air conditioning apparatus which concerns on one Embodiment of this invention. It is the figure which showed an example of the relationship between the on-off state of an indoor fan, and the opening state of an indoor electric expansion valve.

  Hereinafter, an embodiment of a control device and method, a program, and a multi-type air conditioning system including the same according to the present invention will be described with reference to the drawings.

FIG. 1 shows a schematic configuration diagram including a refrigerant cycle of a multi-type air conditioning system 1 including a control device according to the present embodiment.
Here, the multi-type air conditioning system 1 is branched between one outdoor unit 2, a gas side pipe 4 and a liquid side pipe 5 led out from the outdoor unit 2, and the gas side pipe 4 and the liquid side pipe 5. And a plurality of indoor units 7 connected in parallel via the unit 6. In FIG. 1, the case where the indoor units 7 are two indoor units 7A and 7B is shown as an example. Hereinafter, the indoor unit will be described as the indoor unit 7 unless otherwise specified.

  The outdoor unit 2 heats an inverter-driven compressor 21 that compresses refrigerant, an oil separator 22 that separates refrigeration oil from refrigerant gas, a four-way switching valve 23 that switches a refrigerant circulation direction, and refrigerant and outside air. An outdoor heat exchanger 24 to be exchanged, a supercooling coil 25 configured integrally with the outdoor heat exchanger 24, an outdoor electric expansion valve (EEVH) 26 for heating, a receiver 27 for storing liquid refrigerant, A supercooling heat exchanger 28 that supercools the liquid refrigerant, a supercooling electric expansion valve (EEVSC) 29 that controls the amount of refrigerant diverted to the supercooling heat exchanger 28, and a refrigerant sucked into the compressor 21 An accumulator 30 that separates the liquid component from the gas and causes the compressor 21 to suck only the gas component, a gas-side operation valve 31, and a liquid-side operation valve 32 are provided.

  The respective devices on the outdoor unit 2 side are connected in a known manner via refrigerant pipes such as a discharge pipe 33A, a gas pipe 33B, a liquid pipe 33C, a gas pipe 33D, a suction pipe 33E, and a subcooling branch pipe 33F. The outdoor refrigerant circuit 34 is configured. The outdoor unit 2 is provided with an outdoor fan 35 that blows outside air to the outdoor heat exchanger 24.

  Further, between the oil separator 22 and the suction pipe 33E of the compressor 21, a refrigerating machine oil separated from the discharged refrigerant gas in the oil separator 22 is returned to the compressor 21 side by a predetermined amount. A parallel circuit of a first oil return circuit 37 having a fixed throttle (throttle) 36 and a second oil return circuit 40 having a fixed throttle (throttle) 39 such as an electromagnetic valve 38 and a capillary tube is connected.

  The gas side pipe 4 and the liquid side pipe 5 are refrigerant pipes connected to the gas side operation valve 31 and the liquid side operation valve 32 of the outdoor unit 2, and are connected to the outdoor unit 2 and to it during installation on site. The length is set according to the distance between the indoor units 7A and 7B. An appropriate number of branching devices 6 are provided in the middle of the gas side piping 4 and the liquid side piping 5, and an appropriate number of indoor units 7 </ b> A and 7 </ b> B are connected via the branching devices 6. Thereby, one sealed refrigeration cycle 3 is configured.

  The indoor units 7A and 7B include an indoor heat exchanger 71 that exchanges heat between the refrigerant and room air and supplies the air to the room, an indoor electric expansion valve for cooling (electric expansion valve for the indoor unit) (EEVC) 72, And an indoor fan 73 that circulates indoor air through the indoor heat exchanger 71, and is connected to the branching device 6 via the branch gas pipe 4A and the branch liquid pipe 5A on the indoor side.

In the multi-type air conditioner 1 described above, the cooling operation is performed as follows.
The high-temperature and high-pressure refrigerant gas compressed by the compressor 21 is discharged to the discharge pipe 33A, and the oil separator 22 separates the refrigerating machine oil contained in the refrigerant. Thereafter, the refrigerant gas is circulated to the gas pipe 33B side through the four-way switching valve 23, and is heat-exchanged with the outside air blown by the outdoor fan 35 in the outdoor heat exchanger 24 to be condensed and liquefied. The liquid refrigerant is further cooled by the supercooling coil 25, passes through the outdoor electric expansion valve 26, and is temporarily stored in the receiver 27.

  The liquid refrigerant whose circulation amount is adjusted by the receiver 27 is partly divided into the subcooling branch pipe 33F in the process of being circulated through the supercooling heat exchanger 28 via the liquid pipe 33C, and the supercooling electric expansion is performed. Heat is exchanged with the refrigerant adiabatically expanded by the valve (EEVSC) 29 to give a degree of supercooling. This liquid refrigerant is led out from the outdoor unit 2 to the liquid side pipe 5 via the liquid side operation valve 32, and the liquid refrigerant led out to the liquid side pipe 5 is further branched into the indoor units 7A and 7B by the branching device 6. The flow is diverted to the liquid pipes 5A and 5B.

  The liquid refrigerant divided into the branch liquid pipes 5A and 5B flows into the indoor units 7A and 7B, is adiabatically expanded by the indoor electric expansion valve (EEVC) 72, becomes a gas-liquid two-phase flow, and the indoor heat exchanger 71. Is flowed into. In the indoor heat exchanger 71, the indoor air circulated by the indoor fan 73 and the refrigerant are heat-exchanged, and the indoor air is cooled and provided for indoor cooling. On the other hand, the refrigerant is gasified, reaches the branching device 6 through the branch gas pipes 4A and 4B, and merges with the refrigerant gas from the other indoor units in the gas side pipe 4.

  The refrigerant gas merged in the gas side pipe 4 is returned to the outdoor unit 2 side, reaches the suction pipe 33E via the gas side operation valve 31, the gas pipe 33D, and the four-way switching valve 23, and the refrigerant gas from the branch pipe 33F. After being merged, it is introduced into the accumulator 30. In the accumulator 30, the liquid component contained in the refrigerant gas is separated, and only the gas component is sucked into the compressor 21. This refrigerant is compressed again in the compressor 21, and the cooling operation is performed by repeating the above cycle.

On the other hand, the heating operation is performed as follows.
The high-temperature and high-pressure refrigerant gas compressed by the compressor 21 is discharged to the discharge pipe 33A, and after the refrigerating machine oil contained in the refrigerant is separated by the oil separator 22, the four-way switching valve 23 causes the gas pipe 33D side. It is circulated to. The refrigerant is led out from the outdoor unit 2 through the gas side operation valve 31 and the gas side pipe 4, and is further introduced into the indoor units 7A and 7B through the branching unit 6 and the branch gas pipes 4A and 4B on the indoor side.

  The high-temperature and high-pressure refrigerant gas introduced into the indoor units 7A and 7B is heat-exchanged with the indoor air circulated by the indoor fan 73 in the indoor heat exchanger 71, and the indoor air is heated and used for indoor heating. The liquid refrigerant condensed and liquefied in the indoor heat exchanger 71 reaches the branching device 6 through the indoor electric expansion valve (EEVC) 72 and the branch liquid pipes 5A and 5B, and is merged with the refrigerant from other indoor units. It returns to the outdoor unit 2 through the liquid side pipe 5.

  The refrigerant that has returned to the outdoor unit 2 reaches the supercooling heat exchanger 28 via the liquid side operation valve 32 and the liquid pipe 33C, and is given supercooling as in the case of cooling, and then flows into the receiver 27. Once stored, the amount of circulation is adjusted. This liquid refrigerant is supplied to the outdoor electric expansion valve (EEVH) 26 through the liquid pipe 33C, and is adiabatically expanded there, and then flows into the outdoor heat exchanger 24 through the supercooling coil 25.

  In the outdoor heat exchanger 24, heat is exchanged between the outside air blown from the outdoor fan 35 and the refrigerant, and the refrigerant absorbs heat from the outside air and is evaporated and gasified. This refrigerant is merged with the refrigerant from the subcooling branch pipe 33F from the outdoor heat exchanger 24 via the gas pipe 33B, the four-way switching valve 23, and the suction pipe 33E, and is introduced into the accumulator 30. In the accumulator 30, the liquid component contained in the refrigerant gas is separated, and only the gas component is sucked into the compressor 21. This refrigerant is compressed again by the compressor 21, and the heating operation is performed by repeating the above cycle.

  During the cooling operation and heating operation described above, the refrigerating machine oil separated from the discharged refrigerant gas in the oil separator 22 has a first oil return circuit 37 having a fixed throttle 36 connected in parallel to each other, a solenoid valve 38 and a fixed. It is returned to the compressor 21 side through a second oil return circuit 40 having a throttle 39. As a result, a certain amount of refrigerating machine oil is secured in the compressor 21 and the sliding portion in the compressor 21 is lubricated. The solenoid valve 38 provided in the second oil return circuit 40 is opened and closed at an appropriate timing during the normal cooling operation and the heating operation, so that the compressor 21 of the oil separated by the oil separator 22 is operated. The return amount to the side can be adjusted.

  The control unit (control device) 41 turns off the indoor fan (stops rotation) when performing an intermittent operation that repeats an on / off operation of stopping for a predetermined time after the indoor fan of the indoor unit 7 rotates for a predetermined time when the thermo is turned off during heating. During the period, the indoor electric expansion valve of the indoor unit 7 is controlled to an opening larger than the opening during the on (rotation) period of the indoor fan and not more than the opening for noise countermeasures. Specifically, in the control unit 41, a small amount of refrigerant flows such that the indoor electric expansion valve opening degree during the on-period of the indoor fan does not accumulate naturally condensed refrigerant in the heat exchanger of the indoor unit 7. When the state is set to “slightly open”, the opening degree of the indoor electric expansion valve during the off period of the indoor fan is in the range of 1.1 to 2.5 times that of “slightly opening” And urge the refrigerant to escape. Here, the opening degree of the indoor electric expansion valve during the off period of the indoor fan is defined as “slightly opened + α”, and “slightly opened + α” is a state that is opened from the slightly opened state and is less than the opening degree that generates noise. Degree (opening to suppress noise and prevent sound complaints from the surroundings).

FIG. 2 shows the relationship between the on / off state of the indoor fan and the opening state of the indoor electric expansion valve.
When the thermostat is turned off during heating, the indoor fan is intermittently operated to be turned on and off at predetermined intervals. When the indoor fan is in the rotating on state, the opening degree of the indoor electric expansion valve 72 is “slightly open”. Is done. When it is detected that the indoor fan is turned off at time t1, the opening degree of the indoor electric expansion valve 72 is controlled to “slightly open + α” at time t2. At time t3 after the passage of a predetermined period of the indoor fan off period, the opening degree of the indoor electric expansion valve 72 is “slightly open”.

  When the indoor fan is turned on at time t4, the indoor electric expansion valve 72 is kept in the “slightly open” state. When it is detected that the indoor fan is turned off at time t5, the opening degree of the indoor electric expansion valve 72 is set to “slightly open + α” at time t6. As described above, when the indoor fan is in the on state when the thermo is turned off during heating, the opening degree of the indoor electric expansion valve 72 is set to “slightly open”, and when the indoor fan is in the off state, Let it be “fine opening + α”, which is an opening degree that is about 1.1 to 2.5 times larger than “fine opening”.

In the control part 41 which concerns on embodiment mentioned above, it is good also as a structure which processes separately using software in all or one part of the said process. In this case, the control unit 41 includes a main storage device such as a CPU and a RAM, and a computer-readable recording medium on which a program (for example, a control program) for realizing all or part of the above processing is recorded. Yes. Then, the CPU reads out the program recorded in the storage medium and executes information processing and calculation processing, thereby realizing processing similar to that of the control unit 41 described above.
Here, the computer-readable recording medium means a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like. Alternatively, the computer program may be distributed to the computer via a communication line, and the computer that has received the distribution may execute the program.

As described above, according to the control unit 41, the method and the program according to the present embodiment, and the multi-type air conditioning system 1 including the same, the indoor unit 7 that circulates indoor air at the time of the heat-off during heating is used. When performing an intermittent operation that repeats an on / off operation of stopping for a predetermined time after the fan has rotated for a predetermined time, the opening degree of the indoor electric expansion valve during the off period of the indoor fan is larger than the opening degree of the indoor fan during the on period. In addition, the opening is controlled to be equal to or less than the opening for noise countermeasures.
The indoor electric expansion valve is widened during the on-period of the indoor fan by expanding the opening of the indoor fan during the off-period of the indoor fan (that is, the indoor fan does not rotate) than during the on-period of the indoor fan. Compared to the case, overheating can be prevented. In addition, since the indoor electric expansion valve has an opening larger than the opening during the on-period of the indoor fan, the refrigerant can be extracted from the indoor unit 7 in the thermo-off state, and the gas low state of the system can be prevented. Further, since the opening is reduced to an opening equal to or less than the opening for noise countermeasures, the opening is set to an opening equal to or less than the opening at which noise is generated, and countermeasures for sound complaints are taken.

  In the present embodiment, the control unit 41 has been described as controlling the opening degree of the indoor electric expansion valve in a partial period during the off period of the indoor fan. The opening degree of the indoor electric expansion valve is the same as that during the off period of the indoor fan (that is, the off period of the indoor fan coincides with the period in which the opening degree of the indoor electric expansion valve 72 is “slightly open + α”). It may be controlled.

DESCRIPTION OF SYMBOLS 1 Multi-type air conditioning system 2 Outdoor unit 7, 7A, 7B Indoor unit 41 Control part (control apparatus)

Claims (6)

A control device that controls the operation of a multi-type air conditioning system in which a plurality of indoor units are connected to an outdoor unit, and the refrigerant flow rate that is circulated through the refrigerant pipe is adjusted by the opening of an electric expansion valve of the indoor unit. ,
When performing an intermittent operation that repeats an on / off operation in which the indoor fan of the indoor unit that circulates the indoor air rotates for a predetermined time and then stops for a predetermined time when the thermo-off during heating is performed, the indoor unit is turned off during the off period of the indoor fan. The electric expansion valve is controlled to be larger than the opening during the on-period of the indoor fan and less than or equal to the opening for noise countermeasures. When the opening of the electric expansion valve during the on-period of the indoor fan is slightly opened so that a small amount of refrigerant flows so that the naturally condensed refrigerant does not accumulate in the heat exchanger of the indoor unit In addition,
2. The control device according to claim 1, wherein an opening degree of the electric expansion valve during an off period of the indoor fan is an opening degree in a range of 1.1 to 2.5 times with respect to the slight opening.   3. The control device according to claim 1, wherein the opening degree of the electric expansion valve of the indoor unit is controlled in a partial period during an off period of the indoor fan.   The multi-type air conditioning system provided with the control apparatus in any one of Claims 1-3. A control method for controlling the operation of a multi-type air conditioning system in which a plurality of indoor units are connected to an outdoor unit, and the flow rate of refrigerant flowing through the refrigerant pipe is adjusted by the opening of an electric expansion valve of the indoor unit. ,
When performing an intermittent operation that repeats an on / off operation in which the indoor fan of the indoor unit that circulates the indoor air rotates for a predetermined time and then stops for a predetermined time when the thermo-off during heating is performed, the indoor unit is turned off during the off period of the indoor fan. A control method for controlling the electric expansion valve to an opening that is larger than the opening of the indoor fan during the on-period and less than or equal to the opening of noise countermeasures. A control program for controlling the operation of a multi-type air conditioning system in which a plurality of indoor units are connected to an outdoor unit, and the refrigerant flow rate that is circulated through the refrigerant pipe is adjusted by the opening of an electric expansion valve of the indoor unit. ,
When performing an intermittent operation of repeating an on / off operation in which the indoor fan of the indoor unit that circulates indoor air rotates for a predetermined time and stops for a predetermined time when the thermo-off during heating is performed, during the off period of the fan of the indoor unit, A control program for causing a computer to control the electric expansion valve of an indoor unit to an opening larger than an opening of the indoor unit during an ON period and less than an opening for noise countermeasures.

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