Air conditioning system and control method thereof

Patent metadata

Field	Value
Publication number	US-2016252284-A1
Application number	US-201415025794-A
Country	US
Kind code	A1
Filing date	Sep 26, 2014
Priority date	Sep 30, 2013
Publication date	Sep 1, 2016
Grant date	—

Abstract

An air conditioning system includes a plurality of indoor units installed in the same indoor space, an outdoor unit and a control device. The indoor units include respective usage-side heat exchangers capable of setting set temperatures individually. The outdoor unit includes a heat-source-side heat exchanger. The control device performs temperature control using a thermo-ON condition set in advance in accordance with the set temperatures, and relaxes the thermo-ON condition of thermo-OFF indoor units when the indoor units include both those that are thermo-ON and those that are thermo-OFF and a predetermined condition is satisfied. The predetermined condition is that at least one of the plurality of indoor units continues to be thermo-ON for a first elapsed time or longer, and at least one of the plurality of indoor units continues to be thermo-OFF for a second elapsed time or longer.

First claim

What is claimed is:

1 . An air conditioning system, comprising:
a plurality of indoor units installed in a same indoor space, the indoor units including respective usage-side heat exchangers and being capable of setting set temperatures individually; an outdoor unit including a heat-source-side heat exchanger arranged and configured to conduct heat exchange with refrigerant circulating through the usage-side heat exchangers; and a control device configured
to perform temperature control of the same indoor space for each indoor unit, using a thermo-ON condition set in advance in accordance with the set temperatures, and
to relax the thermo-ON condition of thermo-OFF indoor units when the indoor units include both those that are thermo-ON and those that are thermo-OFF and a predetermined condition is satisfied,
the predetermined condition being that at least one of the plurality of indoor units continues to be thermo-ON for a first elapsed time or longer, and at least one of the plurality of indoor units continues to be thermo-OFF for a second elapsed time or longer.

2 . The air conditioning system according to claim 1 , wherein
the control device relaxes the thermo-ON condition without altering a thermo-OFF condition.

3 . The air conditioning system according to claim 1 , wherein
the control device appoints an operating condition of the outdoor unit so as to satisfy a highest increase requirement of increase requirements of air-conditioning capability of the plurality of indoor units.

4 . The air conditioning system according to claim 3 , wherein
the control device has
a required temperature calculation unit configured to calculate required evaporation temperatures or required condensation temperatures of the usage-side heat exchanger for each of the indoor units, and
a target value appointing unit configured to appoint
a target evaporation temperature based on a minimum value of the required evaporation temperatures of the indoor units calculated in the required temperature calculation units, or
a target condensation temperature based on a maximum value of the required condensation temperatures of the indoor units calculated in the required temperature calculation units.

5 . (canceled)

6 . The air conditioning system according to claim 1 , wherein
the thermo-ON condition is a condition that the indoor units be thermo-ON when there is a predetermined temperature difference between the set temperature and a control temperature; and the control device relaxes the thermo-ON condition by reducing the predetermined temperature difference of the thermo-ON condition,

7 . The air conditioning system according to claim 1 , wherein
a plurality of the indoor units further include respective air blowers useable to adjust airflow volumes directed to the usage-side heat exchangers; and the control device adjusts the air blowers of the indoor units to reduce the airflow volumes when air-conditioning capabilities are excessive and to increase the airflow volumes when the air-conditioning capabilities are insufficient.

8 . The air conditioning system according to claim 1 , wherein
the indoor units further include respective expansion mechanisms capable of adjusting degrees of superheat or degrees of subcooling in the outlet sides of the usage-side heat exchangers; and the control device adjusts the opening degrees of the expansion mechanisms in the indoor units to reduce the degrees of superheat or degrees of subcooling when the air-conditioning capabilities are excessive and to increase the degrees of superheat or degrees of subcooling when the air-conditioning capabilities are insufficient.

9 . The air conditioning system according to claim 1 , wherein
the control device is centralized controller that acquires data from the outdoor unit and a plurality of the indoor units and sends data to the outdoor unit and a plurality of the indoor units.

10 . A method for controlling an air conditioning system including:
a plurality of indoor units installed in a same indoor space, the indoor units including respective usage-side heat exchangers and being capable of setting set temperatures individually, and an outdoor unit including a heat-source-side heat exchanger arranged and configured to conduct heat exchange with refrigerant circulating through the usage-side heat exchangers, the method comprising: a first step of causing temperature control of the same indoor space to be performed in each indoor unit, using a thermo-ON condition set in advance in accordance with the set temperatures; and a second step of relaxing the thermo-ON condition of thermo-OFF indoor units when the indoor units include both those that are thermo-ON and those that are thermo-OFF and a predetermined condition is satisfied, the predetermined condition being that at least one of the plurality of indoor units continues to be thermo-ON for a first elapsed time or longer, and at least one of the plurality of indoor units continues to be thermo-OFF for a second elapsed time or longer.

Assignees

• Daikin Ind Ltd

Inventors

• Kibo Kousuke
• Nishimura Tadafumi

Classifications

• F24F11/89

  Arrangement or mounting of control or safety devices · CPC title

• F25B13/00

  Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02) · CPC title

• F24F2140/12

  Heat-exchange fluid pressure · CPC title

• F24F2140/20

  Heat-exchange fluid temperature · CPC title

• F25B49/02 Primary

  for compression type machines, plants or systems · CPC title