JP2010210198A - Method of controlling air conditioning device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of controlling an air conditioning device, surely protecting a refrigerating cycle device and performing an operation according to air conditioning load. <P>SOLUTION: In this method of controlling the air conditioning device including: an outdoor unit 1 having a compressor 2 and an outdoor heat exchanger 3; and an indoor unit 12 having an indoor heat exchanger 14, a condensation temperature zone is divided into four zones of lowering, retaining, rising and recovering. When the condensation temperature goes into the lowering zone, the maximum compressor rotational frequency is limited to a certain rotational frequency Nmax first, then when the condensation temperature is in the lowering zone, the condensation temperature is lowered by lowering the compressor rotational frequency, when the condensation temperature is in the retaining zone, the compressor rotational frequency is retained, when the condensation temperature is in the rising zone, the compressor rotational frequency is raised within the rotational frequency Nmax as an upper limit, and then when the condensation temperature is lowered and the control zone is in the recovering zone, the rotational frequency Nmax is canceled, and the normal control is recovered to prevent high pressure abnormality of the refrigerating cycle. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for controlling an air conditioner.

In the conventional air conditioner control method, a refrigeration cycle device such as a compressor is changed by changing the compressor rotation speed from the temperature detected from the heat exchanger without using a pressure sensor at the time of overload or low load. Is protected (see, for example, Patent Document 1).
Japanese Patent No. 3461027

  However, in the control method of the conventional air conditioner described in Patent Document 1, the rapid increase in the condensation pressure or the evaporating pressure cannot be dealt with suddenly when the load fluctuates, for example, when there is a sudden change such as an atmospheric temperature change or an increase or decrease in the indoor load. There was a problem that the refrigeration cycle equipment could not be protected, such as causing freezing due to a decrease in the temperature, and the noise and vibration increased due to frequent changes in the compressor rotation speed.

  The present invention solves the above-described conventional problems, and is an air conditioning apparatus that can reliably protect a refrigeration cycle device and can perform an operation according to an air conditioning load by optimally controlling the compressor rotation speed. An object is to provide a control method.

  In order to solve the above-described conventional problems, an air conditioner of the present invention is connected to an outdoor unit having a compressor, an outdoor heat exchanger, an outdoor blower, a four-way valve, and a throttle device, and is connected to the outdoor unit. In a control method of an air conditioner that includes an exchanger, an indoor unit having an indoor fan, and a condensing temperature detecting device that detects condensing temperature, and at least performs a cooling operation, a dehumidifying operation, or a heating operation, the condensing temperature region is lowered and maintained. When the detected condensing temperature enters the lowering zone, the maximum compressor speed is first limited to a certain speed Nmax, and then the detected condensing temperature is If it is in the lowering zone, the compressor speed is lowered to lower the condensation temperature. If the detected condensation temperature is in the holding zone, the compressor speed is held and the detected condensation is When the degree is in the rising zone, the compressor speed is increased up to the upper limit of the rotational speed Nmax, the condensation temperature is further lowered, and when the control zone is in the return zone, the rotational speed Nmax is canceled, By returning to normal control, high-pressure abnormalities in the refrigeration cycle can be prevented and the refrigeration cycle equipment can be protected while maintaining the performance of the air conditioner.

The air conditioner of the present invention includes a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, an outdoor unit having a throttle device, and an indoor heat exchanger and an indoor fan connected to the outdoor unit. In the control method of an air conditioner that includes an indoor unit and a condensing temperature detecting device that detects condensing temperature and performs at least a cooling operation, a dehumidifying operation, or a heating operation, four methods of lowering, maintaining, raising, and returning the condensing temperature region When the detected condensing temperature enters the lowering zone divided into control zones, first the maximum compressor speed is limited to a certain speed Nmax, and then the detected condensing temperature is in the lowering zone. If the compressor rotation speed is decreased to lower the condensation temperature and the detected condensation temperature is in the holding zone, the compressor rotation speed is held and the detected condensation temperature is in the rising zone. In this case, the compressor rotational speed is increased up to the upper limit of the rotational speed Nmax, the condensation temperature is further decreased, and when the control zone is in the return zone, the rotational speed Nmax is canceled and the compressor rotational speed is The compressor rotational speed change speed is decreased and increased to the operating rotational speed, so that the stability of the refrigeration cycle can be improved and the abnormality of the refrigeration cycle can be prevented.

  The air conditioner of the present invention includes a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, an outdoor unit having a throttle device, and an indoor heat exchanger and an indoor fan connected to the outdoor unit. In the control method of an air conditioner that includes an indoor unit and a condensing temperature detecting device that detects condensing temperature and performs at least a cooling operation, a dehumidifying operation, or a heating operation, four methods of lowering, maintaining, raising, and returning the condensing temperature region When the detected condensing temperature enters the lowering zone divided into control zones, first the maximum compressor speed is limited to a certain speed Nmax, and then the detected condensing temperature is in the lowering zone. If the compressor rotation speed is decreased to lower the condensation temperature and the detected condensation temperature is in the holding zone, the compressor rotation speed is held and the detected condensation temperature is in the rising zone. In this case, the compressor rotational speed is increased up to the upper limit of the rotational speed Nmax, the condensation temperature decreases, and when the control zone is in the return zone, the rotational speed Nmax is canceled and the compressor rotational speed is reduced to the compressor. Reduces the speed change speed from the normal speed and raises it, and after the set time has elapsed, the compressor speed change speed is returned to the normal speed, reducing the return time to normal control and making it more comfortable than necessary. It is possible to return to normal operation while maintaining stability without being lost.

  The air conditioner of the present invention includes a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, an outdoor unit having a throttle device, and an indoor heat exchanger and an indoor fan connected to the outdoor unit. In an air conditioner control method that includes an indoor unit and an evaporating temperature detecting device that detects evaporating temperature and performs at least a cooling operation, a dehumidifying operation, or a heating operation, the evaporating temperature region is reduced, maintained, increased, and returned to four levels. When divided into control zones and the detected evaporation temperature enters the lowering zone, first, the maximum compressor rotation speed is limited to a certain rotation speed Nmax, and then the detected evaporation temperature is in the lowering zone. When the evaporation temperature is raised by lowering the compressor rotation speed and the detected evaporation temperature is in the holding zone, the compressor rotation speed is held and the detected evaporation temperature is in the rising zone. In this case, the compressor rotational speed is increased to the upper limit of the rotational speed Nmax, the evaporation temperature is further increased, and when the control zone is in the return zone, the rotational speed Nmax is canceled and the normal control is restored. The indoor heat exchanger is prevented from freezing while maintaining the capability of the air conditioner, and the excessive low pressure drop of the refrigeration cycle is prevented.

  The air conditioner of the present invention includes a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, an outdoor unit having a throttle device, and an indoor heat exchanger and an indoor fan connected to the outdoor unit. In an air conditioner control method that includes an indoor unit and an evaporating temperature detecting device that detects evaporating temperature and performs at least a cooling operation, a dehumidifying operation, or a heating operation, the evaporating temperature region is reduced, maintained, increased, and returned to four levels. When divided into control zones and the detected evaporation temperature enters the lowering zone, first, the maximum compressor rotation speed is limited to a certain rotation speed Nmax, and then the detected evaporation temperature is in the lowering zone. When the evaporation temperature is raised by lowering the compressor rotation speed and the detected evaporation temperature is in the holding zone, the compressor rotation speed is held and the detected evaporation temperature is in the rising zone. In this case, the compressor rotational speed is increased up to the upper limit of the rotational speed Nmax, the evaporation temperature is further increased, and when the control zone is in the return zone, the rotational speed Nmax is canceled and the compressor rotational speed is normally operated. The compressor rotational speed change speed is decreased and increased to the rotational speed, so that the refrigeration cycle stability can be improved and the refrigeration cycle abnormality can be prevented.

The air conditioner of the present invention includes a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, an outdoor unit having a throttle device, and an indoor heat exchanger and an indoor fan connected to the outdoor unit. In an air conditioner control method that includes an indoor unit and an evaporating temperature detecting device that detects evaporating temperature and performs at least a cooling operation, a dehumidifying operation, or a heating operation, the evaporating temperature region is reduced, maintained, increased, and returned When divided into control zones and the detected evaporation temperature enters the lowering zone, first, the maximum compressor rotation speed is limited to a certain rotation speed Nmax, and then the detected evaporation temperature is in the lowering zone. When the evaporation temperature is raised by lowering the compressor rotation speed and the detected evaporation temperature is in the holding zone, the compressor rotation speed is held and the detected evaporation temperature is in the rising zone. In the case where the rotation speed Nmax is the upper limit, the rotation speed of the compressor is increased, the evaporation temperature is further increased, and when the control zone is in the return zone, the rotation speed Nmax is canceled and the compressor rotation speed is reduced to the compressor. The speed change speed is decreased and increased, and after the set time has elapsed, the compressor speed change speed is returned to the normal speed, maintaining stability without losing comfort more than necessary. Can return to normal operation.

  In the control method of the air conditioner of the present invention, the upper limit number of revolutions of the compressor is limited at the time of overload or low load, and at the same time, four control areas are set and the number of revolutions of the compressor is changed. Also, the condensation temperature or the evaporation temperature can be maintained, the refrigeration cycle equipment can be protected, and the operation according to the air conditioning load can be performed.

  The first invention includes a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, an outdoor unit having a throttle device, an indoor unit connected to the outdoor unit, an indoor heat exchanger, and an indoor fan, A condensing temperature detecting device for detecting the condensing temperature, and at least a cooling operation, a dehumidifying operation or a heating operation, in the control method of the air conditioner, the condensing temperature region is divided into four control zones: lowering, holding, raising and returning When the detected condensing temperature enters the lowering zone, first, the maximum compressor speed is limited to a certain speed Nmax, and then the compressor rotation is performed when the detected condensing temperature is in the lowering zone. When the detected condensation temperature is in the holding zone, the compressor rotational speed is maintained, and when the detected condensation temperature is in the rising zone, the condensing temperature is decreased. When the compressor rotational speed is increased to the upper limit of the number Nmax, the condensation temperature is lowered, and the control zone is in the return zone, the rotational speed Nmax is canceled and the normal control is restored. While maintaining the capability, it is possible to protect the refrigeration cycle equipment by preventing a high-pressure abnormality in the refrigeration cycle.

  The second invention includes a compressor, an outdoor heat exchanger, an outdoor blower, a four-way valve, an outdoor unit having a throttle device, an indoor unit connected to the outdoor unit, an indoor heat exchanger, and an indoor fan, A condensing temperature detecting device for detecting the condensing temperature, and at least a cooling operation, a dehumidifying operation or a heating operation, in the control method of the air conditioner, the condensing temperature region is divided into four control zones: lowering, holding, raising and returning When the detected condensing temperature enters the lowering zone, first, the maximum compressor speed is limited to a certain speed Nmax, and then the compressor rotation is performed when the detected condensing temperature is in the lowering zone. When the detected condensation temperature is in the holding zone, the compressor rotational speed is maintained, and when the detected condensation temperature is in the rising zone, the condensing temperature is decreased. When the compressor speed is increased up to the upper limit of the number Nmax, the condensing temperature decreases, and the control zone is in the return zone, the speed Nmax is canceled and the compressor speed is compressed to the normal operating speed. The speed of change of the machine speed is decreased and increased, and the stability of the refrigeration cycle can be improved and abnormality of the refrigeration cycle can be prevented.

The third invention includes an outdoor unit having a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, and a throttle device, and an indoor unit having an indoor heat exchanger and an indoor fan connected to the outdoor unit, A condensing temperature detecting device for detecting the condensing temperature, and at least a cooling operation, a dehumidifying operation or a heating operation, in the control method of the air conditioner, the condensing temperature region is divided into four control zones: lowering, holding, raising and returning When the detected condensing temperature enters the lowering zone, first, the maximum compressor speed is limited to a certain speed Nmax, and then the compressor rotation is performed when the detected condensing temperature is in the lowering zone. When the detected condensation temperature is in the holding zone, the compressor rotational speed is maintained, and when the detected condensation temperature is in the rising zone, the condensing temperature is decreased. When the compressor speed is increased up to the upper limit of the number Nmax, the condensing temperature is lowered, and the control zone is in the return zone, the speed Nmax is canceled and the compressor speed is changed to the speed of change of the compressor speed. Reduced to higher than normal, and after the set time has elapsed, the compressor speed change speed is returned to the normal speed, reducing the return time to normal control and stabilizing without losing comfort more than necessary. It is possible to return to normal operation while maintaining the characteristics.

  The fourth invention includes an outdoor unit having a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, and a throttle device, and an indoor unit connected to the outdoor unit and having an indoor heat exchanger and an indoor fan; In an air conditioner control method that includes an evaporating temperature detecting device that detects an evaporating temperature and performs at least a cooling operation, a dehumidifying operation, or a heating operation, the evaporating temperature region is divided into four control zones: decrease, hold, increase, and return When the detected evaporation temperature enters the lowering zone, the maximum compressor rotation speed is first limited to a certain rotation speed Nmax, and then the compressor rotation is performed when the detected evaporation temperature is in the lowering zone. When the detected evaporation temperature is in the holding zone, the compressor rotational speed is maintained.When the detected evaporation temperature is in the increasing zone, the evaporation temperature is increased. When the compressor rotational speed is increased to the upper limit of the number Nmax, the evaporation temperature is further increased, and the control zone is in the return zone, the rotational speed Nmax is canceled and returned to normal control. While maintaining the capacity, the indoor heat exchanger is prevented from freezing, and an excessively low pressure drop of the refrigeration cycle is prevented.

  The fifth invention includes a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, an outdoor unit having a throttle device, an indoor unit connected to the outdoor unit, an indoor heat exchanger, and an indoor fan, In an air conditioner control method that includes an evaporating temperature detecting device that detects an evaporating temperature and performs at least a cooling operation, a dehumidifying operation, or a heating operation, the evaporating temperature region is divided into four control zones: decrease, hold, increase, and return When the detected evaporation temperature enters the lowering zone, the maximum compressor rotation speed is first limited to a certain rotation speed Nmax, and then the compressor rotation is performed when the detected evaporation temperature is in the lowering zone. When the detected evaporation temperature is in the holding zone, the compressor rotational speed is maintained.When the detected evaporation temperature is in the increasing zone, the evaporation temperature is increased. When the compressor rotational speed is increased to the upper limit of the number Nmax, the evaporation temperature is further increased, and the control zone is in the return zone, the rotational speed Nmax is canceled and the compressor rotational speed is increased to the normal operating rotational speed. The rotational speed change speed is decreased and increased, and the stability of the refrigeration cycle can be improved and the abnormality of the refrigeration cycle can be prevented.

  A sixth invention includes a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, an outdoor unit having a throttle device, an indoor unit connected to the outdoor unit, and having an indoor heat exchanger and an indoor fan, In an air conditioner control method that includes an evaporating temperature detecting device that detects an evaporating temperature and performs at least a cooling operation, a dehumidifying operation, or a heating operation, the evaporating temperature region is divided into four control zones: decrease, hold, increase, and return When the detected evaporation temperature enters the lowering zone, the maximum compressor rotation speed is first limited to a certain rotation speed Nmax, and then the compressor rotation is performed when the detected evaporation temperature is in the lowering zone. When the detected evaporation temperature is in the holding zone, the compressor rotational speed is maintained.When the detected evaporation temperature is in the increasing zone, the evaporation temperature is increased. When the compressor rotation speed is increased up to the upper limit of the number Nmax, the evaporation temperature is further increased, and the control zone is in the return zone, the rotation speed Nmax is canceled and the compressor rotation speed is changed to the compressor rotation speed change speed. It is lowered and raised from the normal level, and after the set time has elapsed, the compressor speed change speed is returned to the normal speed, and it can return to normal operation while maintaining stability without losing comfort more than necessary. .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a refrigeration cycle diagram of an air conditioner using the control method for an air conditioner according to Embodiment 1 of the present invention, and FIG. 2 is a conceptual diagram of a condensation temperature region of the air conditioner.

In FIG. 1, an air conditioner using the control method for an air conditioner in the present embodiment includes an outdoor unit 1 and an indoor unit 12 connected to the outdoor unit 1 via connection pipes 5b and 6b. The outdoor unit 1 includes a compressor 2 having a variable speed, an outdoor heat exchanger 3, an outdoor blower 4, a refrigerant liquid pipe 5a, a refrigerant gas pipe 6a, a four-way valve 7 for switching between heating and cooling, and a throttle device. 8 is provided.
The outdoor unit 1 is provided with an outdoor heat exchanger temperature detection device 9 that detects the temperature of the outdoor heat exchanger 3 and an outdoor air temperature detection device 10 that detects the outdoor air temperature.

  On the other hand, the indoor unit 12 includes an indoor blower 13, an indoor heat exchanger 14, an indoor heat exchanger temperature detection device 15 that detects the temperature of the indoor heat exchanger 14, and an indoor suction temperature detection that detects the room temperature of the room. A device 16 and an operation setting device 17 capable of setting an operation mode (cooling, dehumidification or heating) desired by the occupant, room temperature, operation or stop, air volume and direction are provided. And the outdoor unit 1 and the indoor unit 12 are connected by the connection piping 5b and 6b, and the refrigerating cycle is comprised.

  The condensation temperature is detected by the outdoor heat exchanger temperature detection device 9 attached to the outdoor heat exchanger 3 in the case of the cooling operation, and the indoor heat exchanger temperature attached to the indoor heat exchanger 14 in the case of the heating operation. It is detected by the detection device 15. That is, in the present embodiment, the outdoor heat exchanger temperature detection device 9 serves as a condensation temperature detection device during cooling operation, and the indoor heat exchanger temperature detection device 15 serves as a condensation temperature detection device during heating.

  As shown in FIG. 2, the condensation temperature region is divided into four control zones: decrease, hold, increase, and return, and when the detected condensation temperature enters the decrease zone (for example, 60 ° C. or higher), the maximum compression is performed first. The machine speed is limited to a certain speed Nmax (for example, 70 rps). If the detected condensation temperature is in the lowering zone even if the compressor speed is lowered, the compressor speed is lowered and the condensation temperature is further lowered.

  When the condensation temperature falls and enters the holding zone (for example, 56 ° C. to 60 ° C.), an operation is performed to keep the compressor speed and keep the condensation temperature. When the detected condensing temperature further falls and enters the rising zone (for example, from 52 ° C. to 56 ° C.), the compressor rotational speed is increased with the rotational speed Nmax as the upper limit. In this case, the compressor speed increase speed is set at a slow speed (for example, 1 Hz / 30 seconds) in order to give priority to stability. When the condensation temperature rises and moves from the rising zone to the holding zone, the holding zone is operated to stabilize the refrigeration cycle by holding the compressor speed.

  When the condensing temperature falls further due to load fluctuation, etc., and the control zone enters the return zone (for example, 52 ° C. or lower), the upper limit rotational speed Nmax is canceled and the rotational speed of the compressor 2 is increased to the normal rotational speed, and normal control is performed. Return to.

  By operating in this way, it is possible to prevent a high-pressure abnormality in the refrigeration cycle while maintaining the performance of the air conditioner.

(Embodiment 2)
Next, the control method of the air conditioning apparatus in Embodiment 2 of this invention is demonstrated. Since the refrigeration cycle diagram and the condensation temperature region conceptual diagram of the air conditioner in the present embodiment are the same as those described in the first embodiment, description thereof will be omitted. In addition, the control method of the air conditioner in the present embodiment is different only in the operation of the return zone. This is the same as described in 1.

  The operation of the return zone will be described. When the condensing temperature falls and the control zone enters the return zone (for example, 52 ° C. or less), the upper limit rotational speed Nmax is canceled and the rotational speed of the compressor 2 is increased to the normal rotational speed to return to the normal control. However, the compressor rotation speed changing speed in the normal control is generally set fast (for example, 1 Hz / 1 second), and the compressor rotation speed increases rapidly.

  Even though the load is lighter, a sudden increase in the compressor rotation speed may cause a sudden rise in the condensation temperature, leading to a protection rush or a protection stop. In order to prevent this, in this embodiment, even in the return zone, the compressor speed increase rate is set gently (for example, 1 Hz / 30 seconds) to improve the refrigeration cycle stability and to improve the refrigeration cycle abnormality. Can be prevented.

(Embodiment 3)
Next, a control method for the air-conditioning apparatus according to Embodiment 3 of the present invention will be described. Since the refrigeration cycle diagram and the condensation temperature region conceptual diagram of the air conditioner in the present embodiment are the same as those described in the first embodiment, description thereof will be omitted. In addition, the control method of the air conditioner in the present embodiment is different only in the operation of the return zone. This is the same as described in 1.

  The operation of the return zone will be described. When the condensation temperature falls and the control zone enters the return zone (for example, 52 ° C. or lower), the upper limit rotational speed Nmax is canceled and the compressor 2 is gradually increased to the normal rotational speed (for example, 1 Hz / 30 seconds) The normal control is restored, but if the difference between the normal compressor speed and the compressor speed reduced by the protection is small, the normal control is immediately resumed and there is no problem in stability.

  However, if the protection is greatly increased transiently at the time of start-up, and the difference between the normal compressor speed and the compressor speed reduced by the protection is large, for example, the normal speed is reduced to 80 Hz by reducing the rotational speed to 30 Hz. Then, it takes a very long time (in this case, 25 minutes) to return to the target normal rotation speed, and comfort is impaired. Therefore, when entering the return zone, the timer (not shown) is operated at the same time as the start of the return operation, and it returns at a moderate speed only during the timer setting time (for example, 5 minutes). After the timer setting time has elapsed, the speed is changed to the normal speed. Then, the normal control is promptly restored.

  This control can return to normal operation while maintaining stability without losing comfort more than necessary.

(Embodiment 4)
FIG. 3 is a conceptual diagram of the evaporation temperature region of the air-conditioning apparatus according to Embodiment 4 of the present invention. In addition, the same code | symbol is attached | subjected to the same part as the air conditioning apparatus in the said Embodiment 1, and the description is abbreviate | omitted.

The evaporating temperature is detected by the indoor heat exchanger temperature detector 15 attached to the indoor heat exchanger 14 in the cooling operation, and the outdoor heat exchanger attached to the outdoor unit heat exchanger 3 in the heating operation. The temperature is detected by the temperature detector 9. That is, in the present embodiment, the indoor heat exchanger temperature detection device 15 serves as an evaporation temperature detection device during cooling operation, and the outdoor heat exchanger temperature detection device 9 serves as an evaporation temperature detection device during heating.

  As shown in FIG. 3, when the evaporation temperature region is divided into four control zones of decrease, hold, increase, and return, and the detected evaporation temperature enters the rotation speed decrease zone (for example, 1 ° C. or less), First, the maximum compressor rotation speed is limited to a certain rotation speed Nmax (for example, 70 rps). If the detected evaporation temperature is in the lowering zone even when the compressor rotational speed decreases, the compressor rotational speed is decreased and the evaporation temperature is further increased.

  When the evaporation temperature rises and enters the holding zone (for example, 1 ° C. to 5 ° C.), an operation is performed to maintain the compressor rotation speed and maintain the evaporation temperature.

  When the detected evaporation temperature further rises and enters the rising zone (for example, 5 ° C. to 10 ° C.), the rotational speed of the compressor is increased with the rotational speed Nmax as the upper limit. In this case, the compressor speed increase speed is set at a slow speed (for example, 1 Hz / 30 seconds) in order to give priority to stability. If the evaporation temperature falls and moves from the rising zone to the holding zone, the holding zone is operated, and the compressor rotation speed is held to stabilize the refrigeration cycle.

  When the evaporation temperature rises further due to load fluctuation and the control zone enters the return zone (for example, 10 ° C. or higher), the upper limit rotational speed Nmax is canceled, the compressor 2 is increased to the normal rotational speed, and normal control is performed. Return.

  By operating the air conditioner in this way, it is possible to prevent the indoor heat exchanger 14 from freezing while maintaining the capability of the air conditioner, and to prevent an excessively low pressure drop in the refrigeration cycle.

(Embodiment 5)
Next, the control method of the air conditioning apparatus in Embodiment 5 of this invention is demonstrated. The refrigeration cycle diagram of the air conditioner in the present embodiment is the same as that in the first embodiment, and the conceptual diagram of the evaporation temperature region is the same as that in the fourth embodiment. Further, the control method of the air conditioner in the present embodiment is different only in the operation of the return zone. Since it is the same as that described in FIG. 4, the description thereof is omitted.

  The operation of the return zone in the control method of the air conditioner in the present embodiment will be described.

  When the evaporation temperature rises and the control zone enters the return zone (for example, 10 ° C. or higher), the upper limit rotational speed Nmax is canceled, the compressor 2 is increased to the normal rotational speed, and the normal control is restored. In general control, the compressor rotation speed changing speed is generally set fast (for example, 1 Hz / 1 second), and the compressor rotation speed increases rapidly. Although the low pressure of the refrigeration cycle can be ensured, a rapid increase in the number of revolutions of the compressor causes a sudden drop in the evaporation temperature, leading to a protection rush, or a protection stop due to freezing of the indoor heat exchanger 14 or an abnormal low pressure drop. There is a case. In order to prevent this, the compressor rotational speed increase speed is set moderately (for example, 1 Hz / 30 seconds) even in the return zone to improve the refrigeration cycle stability and prevent the refrigeration cycle from being abnormal.

(Embodiment 6)
Next, a control method for the air-conditioning apparatus according to Embodiment 6 of the present invention will be described. The refrigeration cycle diagram of the air conditioner in the present embodiment is the same as that in the first embodiment, and the conceptual diagram of the evaporation temperature region is the same as that in the fourth embodiment. Further, the control method of the air conditioner in the present embodiment is different only in the operation of the return zone. Since it is the same as that described in FIG. 4, the description thereof is omitted.

  The operation of the return zone in the control method of the air conditioner in the present embodiment will be described.

  When the evaporation temperature rises and the control zone enters the return zone (for example, 10 ° C. or higher), the upper limit rotational speed Nmax is canceled and the compressor 2 is gradually increased (for example, 1 Hz / 30 seconds) to the normal rotational speed. The normal control is restored, but if the difference between the normal compressor speed and the compressor speed reduced by the protection is small, the normal control is immediately resumed and there is no problem with stability. However, when protection is greatly increased at the time of start-up and the difference between the normal compressor speed and the compressor speed reduced by the protection is large, for example, the normal speed is 80 Hz, and the speed reduced by the protection is If it is set to 30 Hz, it takes a very long time (25 minutes in this case) to return to the target normal rotation speed, and comfort is impaired.

  Therefore, the vehicle enters the return zone, starts the return operation, operates the timer, returns at a moderate speed only during the timer setting time (for example, 5 minutes), changes to the normal speed after the timer ends, and immediately returns to normal control. It is what I did.

  By this control, it is possible to return to normal operation while maintaining stability without losing comfort more than necessary.

  As described above, the control method of the air conditioner according to the present invention can achieve a great effect by applying it to a multi-room type air conditioner having a larger indoor load fluctuation.

Refrigeration cycle diagram of an air conditioner using the control method for an air conditioner according to Embodiment 1 of the present invention. Condensation temperature region conceptual diagram of the air conditioner Evaporation temperature region conceptual diagram of the air-conditioning apparatus according to Embodiment 4 of the present invention.

DESCRIPTION OF SYMBOLS 1 Outdoor unit 2 Compressor 3 Outdoor heat exchanger 4 Outdoor fan 7 Four-way valve 8 Throttle device 9 Outdoor heat exchanger temperature detection device (condensation temperature detection device, evaporation temperature detection device)
DESCRIPTION OF SYMBOLS 12 Indoor unit 13 Indoor fan 14 Indoor heat exchanger 15 Indoor heat exchanger temperature detection apparatus (condensation temperature detection apparatus, evaporation temperature detection apparatus)

Claims (6)

A compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, an outdoor unit having a throttle device, an indoor unit connected to the outdoor unit and having an indoor heat exchanger, an indoor fan, and a condensation for detecting a condensation temperature In a control method of an air conditioner that includes a temperature detection device and performs at least a cooling operation, a dehumidifying operation, or a heating operation, the condensation temperature region is divided into four control zones: decrease, hold, increase, and return, and the detected condensation temperature Enters the lowering zone, first the maximum compressor speed is limited to a certain speed Nmax, and if the detected condensation temperature is in the lowering zone, the compressor speed is decreased to condense. When the temperature is lowered and the detected condensation temperature is in the holding zone, the compressor rotation speed is held, and when the detected condensation temperature is in the rising zone, the rotation speed Nmax is set. The control of the air conditioner is characterized in that when the compressor rotational speed is increased as much as possible, the condensation temperature is lowered, and the control zone is in the return zone, the rotational speed Nmax is canceled and the normal control is restored. Method. A compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, an outdoor unit having a throttle device, an indoor unit connected to the outdoor unit and having an indoor heat exchanger, an indoor fan, and a condensation for detecting a condensation temperature In a control method of an air conditioner that includes a temperature detection device and performs at least a cooling operation, a dehumidifying operation, or a heating operation, the condensation temperature region is divided into four control zones: decrease, hold, increase, and return, and the detected condensation temperature Enters the lowering zone, first the maximum compressor speed is limited to a certain speed Nmax, and if the detected condensation temperature is in the lowering zone, the compressor speed is decreased to condense. When the temperature is lowered and the detected condensation temperature is in the holding zone, the compressor rotation speed is held, and when the detected condensation temperature is in the rising zone, the rotation speed Nmax is set. When the compressor speed is increased to the limit, the condensing temperature is lowered, and the control zone is in the return zone, the speed Nmax is canceled and the compressor speed is increased to the normal operation speed. A control method for an air conditioner, wherein the change speed is increased and decreased. A compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, an outdoor unit having a throttle device, an indoor unit connected to the outdoor unit and having an indoor heat exchanger, an indoor fan, and a condensation for detecting a condensation temperature In a control method of an air conditioner that includes a temperature detection device and performs at least a cooling operation, a dehumidifying operation, or a heating operation, the condensation temperature region is divided into four control zones: decrease, hold, increase, and return, and the detected condensation temperature Enters the lowering zone, first the maximum compressor speed is limited to a certain speed Nmax, and if the detected condensation temperature is in the lowering zone, the compressor speed is decreased to condense. When the temperature is lowered and the detected condensation temperature is in the holding zone, the compressor rotation speed is held, and when the detected condensation temperature is in the rising zone, the rotation speed Nmax is set. When the compressor speed is increased to the limit, the condensing temperature is lowered, and the control zone is in the return zone, the speed Nmax is canceled and the compressor speed is changed from the normal speed. A method for controlling an air conditioner, wherein the compressor speed change speed is returned to a normal speed after the set time has elapsed. An outdoor unit having a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, a throttle device, an indoor unit connected to the outdoor unit and having an indoor heat exchanger and an indoor fan, and evaporation for detecting an evaporation temperature In a control method of an air conditioner that includes a temperature detection device and performs at least a cooling operation, a dehumidifying operation, or a heating operation, the evaporation temperature region is divided into four control zones of decrease, hold, increase, and return, and the detected evaporation temperature Enters the lowering zone, the maximum compressor rotation speed is first limited to a certain rotation speed Nmax. After that, when the detected evaporation temperature is in the lowering zone, the compressor rotation speed is decreased to evaporate. When the detected evaporation temperature is in the holding zone, the compressor rotational speed is maintained, and when the detected evaporation temperature is in the rising zone, the rotational speed Nmax is When the compressor rotational speed is increased to the limit, the evaporation temperature is further increased, and the control zone is in the return zone, the rotational speed Nmax is canceled and the control is returned to the normal control. Method. An outdoor unit having a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, a throttle device, an indoor unit connected to the outdoor unit and having an indoor heat exchanger and an indoor fan, and evaporation for detecting an evaporation temperature In a control method of an air conditioner that includes a temperature detection device and performs at least a cooling operation, a dehumidifying operation, or a heating operation, the evaporation temperature region is divided into four control zones of decrease, hold, increase, and return, and the detected evaporation temperature Enters the lowering zone, the maximum compressor rotation speed is first limited to a certain rotation speed Nmax. After that, when the detected evaporation temperature is in the lowering zone, the compressor rotation speed is decreased to evaporate. When the detected evaporation temperature is in the holding zone, the compressor rotational speed is maintained, and when the detected evaporation temperature is in the rising zone, the rotational speed Nmax is When the compressor speed is increased to the limit, the evaporation temperature is further raised, and the control zone is in the return zone, the speed Nmax is canceled and the compressor speed is changed to the normal speed. A control method for an air conditioner, wherein the speed is increased and decreased. An outdoor unit having a compressor, an outdoor heat exchanger, an outdoor fan, a four-way valve, a throttle device, an indoor unit connected to the outdoor unit and having an indoor heat exchanger and an indoor fan, and evaporation for detecting an evaporation temperature In a control method of an air conditioner that includes a temperature detection device and performs at least a cooling operation, a dehumidifying operation, or a heating operation, the evaporation temperature region is divided into four control zones of decrease, hold, increase, and return, and the detected evaporation temperature Enters the lowering zone, the maximum compressor rotation speed is first limited to a certain rotation speed Nmax. After that, when the detected evaporation temperature is in the lowering zone, the compressor rotation speed is decreased to evaporate. When the detected evaporation temperature is in the holding zone, the compressor rotational speed is maintained, and when the detected evaporation temperature is in the rising zone, the rotational speed Nmax is If the compressor rotational speed is increased to the limit, the evaporation temperature is further increased, and the control zone is in the return zone, the rotational speed Nmax is cancelled, and the compressor rotational speed is changed from the normal speed of the compressor rotational speed. A method for controlling an air conditioner, wherein the compressor speed change speed is returned to a normal speed after the set time has elapsed.