Air conditioning system and method for controlling the same

Abstract

The present invention relates to air conditioning systems, and more particularly, to an air conditioning system which can control a refrigerant flow rate to a heat exchanger exchanging heat with room air to be optimum; and a method for controlling the same. The air conditioning system includes an outdoor heat exchange part including a compressor for compressing refrigerant, an outdoor heat exchanger for making the refrigerant to heat exchange with outdoor air, and an expansion device for expanding the refrigerant, an indoor heat exchange part including a pump for making refrigerant in a flow path independent from the outdoor heat exchange part to flow, at least one indoor heat exchanger for making the refrigerant heat exchange with room air, and a flow rate control device for controlling a flow rate of the refrigerant, and a hybrid heat exchange part for making the outdoor heat exchange part and the indoor heat exchange part, which are independent from each other, to heat exchange with each other. According to this, the air conditioning system can be installed on a multistory building without limitation of a height of the building as far as a capacity of the pump permits. Moreover, even if a refrigerant pipe is long, the air conditioning system is applicable even to a system with a refrigerant pipe line longer than the related art as far as the capacity of the pump permits, and fine control of a room air temperature is possible.

1 . An air conditioning system comprising: 
 an outdoor heat exchange part including a compressor for compressing refrigerant, an outdoor heat exchanger for making the refrigerant to heat exchange with outdoor air, and an expansion device for expanding the refrigerant;    an indoor heat exchange part including a pump for making refrigerant in a flow path independent from the outdoor heat exchange part to flow, an indoor heat exchanger for making the refrigerant heat exchange with room air, and a flow rate control device for controlling a flow rate of the refrigerant; and    a hybrid heat exchange part for making the outdoor heat exchange part and the indoor heat exchange part, which are independent from each other, to heat exchange with each other.    
   
   
       2 . The system as claimed in  claim 1 , wherein the flow rate control device includes; 
 a temperature sensor for measuring temperatures of refrigerant flowing in the indoor heat exchanger,    a controller for determining a degree of superheat or subcooling of the refrigerant with the temperatures measured at the temperature sensors, and    a flow rate control valve for controlling a refrigerant flow rate to the indoor heat exchanger according to the determination of the controller.    
   
   
       3 . The system as claimed in  claim 2 , wherein the flow rate control valve is mounted on a refrigerant inlet end of the indoor heat exchanger.  
   
   
       4 . The system as claimed in  claim 2 , wherein the flow rate control valve is mounted on a refrigerant outlet end of the indoor heat exchanger.  
   
   
       5 . The system as claimed in  claim 2 , wherein the temperature sensors are mounted on the refrigerant inlet end, the refrigerant outlet end, and a predetermined portion between the refrigerant inlet end and the refrigerant outlet end of the indoor heat exchanger.  
   
   
       6 . The system as claimed in  claim 5 , wherein the predetermined portion between the refrigerant inlet end and the refrigerant outlet end of the indoor heat exchanger is a section in which the refrigerant flowing in the indoor heat exchanger is in a saturated state.  
   
   
       7 . A method for controlling an air conditioning system comprising the steps of: 
 setting an ideal degree of superheat, and an ideal degree of subcooling at a controller;    comparing the degree of superheat or subcooling set thus with a degree of superheat or subcooling measured thus; and    controlling a flow rate of refrigerant flowing in an indoor heat exchanger according to a result of the step of comparing the degree of superheat or subcooling set thus with a degree of superheat or subcooling measured thus.    
   
   
       8 . The method as claimed in  claim 7 , wherein the degree of superheat or subcooling is a difference between a temperature of the refrigerant at the refrigerant outlet of the indoor heat exchanger and a saturation temperature of the refrigerant flowing in the indoor heat exchanger.  
   
   
       9 . The method as claimed in  claim 7 , wherein the step of controlling a flow rate of refrigerant flowing in an indoor heat exchanger includes the steps of; 
 increasing the flow rate of the refrigerant flowing in the indoor heat exchanger if the degree of superheat measured is higher than the degree of superheat set, and    decreasing the flow rate of the refrigerant flowing in the indoor heat exchanger if the degree of superheat measured is lower than the degree of superheat set.    
   
   
       10 . The method as claimed in  claim 7 , wherein the step of controlling a flow rate of refrigerant flowing in an indoor heat exchanger includes the steps of; 
 increasing the flow rate of the refrigerant flowing in the indoor heat exchanger if the degree of subcooling measured is higher than the degree of subcooling set, and    decreasing the flow rate of the refrigerant flowing in the indoor heat exchanger if the degree of subcooling measured is lower than the degree of subcooling set.    
   
   
       11 . An air conditioning system comprising: 
 at least one first heat exchanger for heat exchange with room air;    a second heat exchanger for transferring heat from the first heat exchanger to an outside of a refrigerant flow path having the first heat exchanger mounted therein;    a pump for circulating the refrigerant to the first heat exchanger and the second heat exchanger;    a third heat exchanger in a flow path independent both from the first heat exchanger and the second heat exchanger for heat exchange with the second heat exchanger;    a fourth heat exchanger for transferring heat from the third heat exchanger to outdoor air;    a compressor for compressing the refrigerant and circulating the refrigerant to the third heat exchanger and the fourth heat exchanger;    a plurality of temperature sensors for measuring temperatures of the refrigerant flowing in the first heat exchanger; and    at least one flow rate control valve for controlling a flow rate of the refrigerant flowing in the first heat exchanger according to temperatures measured at the temperature sensors.    
   
   
       12 . The system as claimed in  claim 11 , wherein the temperature sensors are provided at a refrigerant inlet end and a refrigerant outlet end of the first heat exchanger, and at a predetermined portion between the refrigerant inlet end and the refrigerant outlet end, respectively.  
   
   
       13 . The system as claimed in  claim 11 , wherein the temperature sensor provided at a predetermined portion between the refrigerant inlet end and the refrigerant outlet end measures a saturation temperature of the refrigerant flowing in the first heat exchanger.  
   
   
       14 . The system as claimed in  claim 11 , wherein the flow rate control valves are provided to a refrigerant inlet end and a refrigerant outlet end of the indoor heat exchanger.  
   
   
       15 . The system as claimed in  claim 14 , wherein, at the time of controlling a refrigerant flow rate, an opening of the flow rate control valve at the refrigerant inlet end of the first heat exchanger is adjusted, and an opening of the flow rate control valve at the refrigerant outlet end is opened to the maximum.