Cogeneration system

Abstract

A cogeneration system according to the present invention includes a waste heat supply heat exchanger that supplies waste heat, which is recovered from an engine, to a suction unit side of a compressor. Accordingly, the present invention is advantageous in that it can maximize the use efficiency of the waste heat. Furthermore, a low compression inverter type compressor having a compression ratio of 1.5 to 2.5, which is lower than that of the related art, is used. Therefore, the present invention is advantageous in that it can maximize the efficiency of the system since the waste heat supplied from the waste heat supply heat exchanger can be utilized to a greater extent. The present invention is also advantageous in that it can prevent damage to the compressor and can save consumption power since a difference in pressure between the suction and discharge units of the compressor becomes small.

1 . A cogeneration system comprising: 
 a generator that generates electric power;    a driving source that drives the generator and generates heat;    waste heat recovery means that recovers waste heat of the driving source;    an air conditioner including a compressor, a 4-way valve, indoor heat exchangers, expansion valves and an outdoor heat exchanger; and    a waste heat supply heat exchanger for supplying the heat, which is recovered from the waste heat recovery means, to a suction unit side of the compressor,    wherein the compressor has a compression ratio of 1.5 to 2.5.    
   
   
       2 . The cogeneration system as claimed in  claim 1 , wherein the compressor is a low compression inverter type compressor having a variable compression ratio.  
   
   
       3 . The cogeneration system as claimed in  claim 1 , wherein the air conditioner further comprises a high compression constant speed type compressor having a compression ratio of 3, 4 or 5.  
   
   
       4 . The cogeneration system as claimed in  claim 1 , wherein the air conditioner further comprises a high compression inverter type compressor having a compression ratio having a compression ratio of 3 to 5.  
   
   
       5 . The cogeneration system as claimed in  claim 1 , wherein the cogeneration system further comprises a bypass flow path along which the refrigerants, which have passed the expansion valves, bypass the outdoor heat exchangers during the heating operation of the air conditioner.  
   
   
       6 . The cogeneration system as claimed in  claim 5 , wherein the outdoor expansion valve for expanding the refrigerants introduced from an indoor unit side is disposed on the suction unit side of the bypass flow path, and 
 a third check valve for preventing the refrigerants, which are sucked into the outdoor heat exchanger, from flowing backward into the bypass flow path during the air cooling operation is disposed on the discharge unit side of the bypass flow path.    
   
   
       7 . The cogeneration system as claimed in  claim 1 , wherein the waste heat recovery means comprises: 
 exhaust gas heat exchangers for recovering the heat of an exhaust gas discharged from the driving source; and    a coolant heat exchanger for recovering the heat of the coolant that has cooled the driving source.    
   
   
       8 . The cogeneration system as claimed in  claim 7 , wherein the cogeneration system further comprises heat dissipation means for dissipating the heat, which is recovered from the coolant heat exchanger and the exhaust gas heat exchangers to the outside during the air cooling operation of the air conditioner.  
   
   
       9 . The cogeneration system as claimed in  claim 1 , wherein the waste heat supply heat exchanger is disposed parallel to the outdoor heat exchanger on a refrigerant circulation flow path along which the refrigerants that are circulated through the air conditioner are guided.  
   
   
       10 . The cogeneration system as claimed in  claim 9 , wherein an air cooling flow path for causing the refrigerants discharged from the first and second compressors to bypass the waste heat supply heat exchanger during the air cooling operation is disposed between the flow paths of inlet and outlet sides of the waste heat supply heat exchanger.