Air conditioner

Abstract

In an air conditioner that uses a refrigerant mixture containing at least 1,2-difluoroethylene, high efficiency is achieved. The motor rotation rate of a compressor ( 100 ) can be changed in accordance with an air conditioning load, and thus a high annual performance factor (APF) can be achieved. In addition, an electrolytic capacitor is not required on an output side of a rectifier circuit ( 21 ), and thus an increase in the size and cost of the circuit is suppressed.

1 . An air conditioner comprising:
 a compressor ( 100 ) that compresses a refrigerant mixture containing at least 1,2-difluoroethylene;   a motor ( 70 ) that drives the compressor ( 100 ); and   a power conversion device ( 30 ,  130 ,  30 B,  130 B,  30 C,  130 C) that is connected between an alternating-current (AC) power source and the motor ( 70 ), that has a switching element, and that controls the switching element such that an output of the motor ( 70 ) becomes a target value.   
     
     
         2 . The air conditioner according to  claim 1 , wherein
 the power conversion device ( 30 ,  130 ) includes   a rectifier circuit ( 21 ) that rectifies an AC voltage of the AC power source, and   a capacitor ( 22 ) that is connected in parallel to an output side of the rectifier circuit ( 21 ) and smooths voltage variation caused by switching in the power conversion device ( 30 ).   
     
     
         3 . The air conditioner according to  claim 1 , wherein the AC power source is a single-phase power source. 
     
     
         4 . The air conditioner according to  claim 1 , wherein the AC power source is a three-phase power source. 
     
     
         5 . The air conditioner according to  claim 1 , wherein the power conversion device ( 30 B,  130 B) is an indirect matrix converter including
 a converter ( 27 ) that receives an AC voltage of the AC power source and converts the AC voltage into a direct-current (DC) voltage, and   an inverter ( 25 ) that converts the DC voltage into an AC voltage and supplies the AC voltage to the motor.   
     
     
         6 . The air conditioner according to  claim 1 , wherein the power conversion device ( 30 C,  130 C) is a matrix converter that directly converts an AC voltage of the AC power source into an AC voltage having a predetermined frequency and supplies the AC voltage having the predetermined frequency to the motor. 
     
     
         7 . The air conditioner according to  claim 1 , wherein the compressor ( 100 ) is any one of a scroll compressor, a rotary compressor, a turbo compressor, and a screw compressor. 
     
     
         8 . The air conditioner according to  claim 1 , wherein the motor ( 70 ) is a permanent magnet synchronous motor having a rotor ( 71 ) including a permanent magnet. 
     
     
         9 . The air conditioner according to  claim 1 ,
 wherein   the refrigerant comprises trans-1,2-difluoroethylene (HFO-1132(E)), difluoromethane (R32), and 2,3,3,3-tetrafluoro-1-propene (R1234yf), wherein   when the mass % of HFO-1132(E), R32, and R1234yf based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), R32, and R1234yf is 100 mass % are within the range of a figure surrounded by line segments IJ, JN, NE, and EI that connect the following 4 points:   
       point I (72.0, 0.0, 28.0), 
       point J (48.5, 18.3, 33.2), 
       point N (27.7, 18.2, 54.1), and 
       point E (58.3, 0.0, 41.7), 
       or on these line segments (excluding the points on the line segment EI;
 the line segment IJ is represented by coordinates (0.0236y 2 −1.7616y+72.0, y, −0.0236y 2 +0.7616y+28.0); 
 the line segment NE is represented by coordinates (0.012y 2 −1.9003y+58.3, y, −0.012y 2 +0.9003y+41.7); and 
 the line segments JN and EI are straight lines. 
 
     
     
         10 . The air conditioner according to  claim 1 ,
 wherein   the refrigerant comprises HFO-1132(E), R32, and R1234yf, wherein   when the mass % of HFO-1132(E), R32, and R1234yf based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), R32, and R1234yf is 100 mass % are within the range of a figure surrounded by line segments MM′, M′N, NV, VG, and GM that connect the following 5 points:   
       point M (52.6, 0.0, 47.4), 
       point M′ (39.2, 5.0, 55.8), 
       point N (27.7, 18.2, 54.1), 
       point V (11.0, 18.1, 70.9), and 
       point G (39.6, 0.0, 60.4), 
       or on these line segments (excluding the points on the line segment GM);
 the line segment MM′ is represented by coordinates (0.132y 2 −3.34y+52.6, y, −0.132y 2 +2.34y+47.4); 
 the line segment M′N is represented by coordinates (0.0596y 2 −2.2541y+48.98, y, −0.0596y 2 +1.2541y+51.02); 
 the line segment VG is represented by coordinates (0.0123y 2 −1.8033y+39.6, y, −0.0123y 2 +0.8033y+60.4); and 
 the line segments NV and GM are straight lines. 
 
     
     
         11 . The air conditioner according to  claim 1 ,
 wherein   the refrigerant comprises HFO-1132(E), R32, and R1234yf, wherein   when the mass % of HFO-1132(E), R32, and R1234yf based on their sum in the refrigerant is respectively represented by x, y and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), R32, and R1234yf is 100 mass % are within the range of a figure surrounded by line segments ON, NU, and UO that connect the following 3 points:   
       point O (22.6, 36.8, 40.6), 
       point N (27.7, 18.2, 54.1), and 
       point U (3.9, 36.7, 59.4), 
       or on these line segments;
 the line segment ON is represented by coordinates (0.0072y 2 −0.6701y+37.512, y, −0.0072y 2 −0.3299y+62.488); 
 the line segment NU is represented by coordinates (0.0083y 2 −1.7403y+56.635, y, −0.0083y 2 +0.7403y+43.365); and 
 the line segment UO is a straight line. 
 
     
     
         12 . The air conditioner according to  claim 1 ,
 wherein   the refrigerant comprises HFO-1132(E), R32, and R1234yf, wherein   when the mass % of HFO-1132(E), R32, and R1234yf based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), R32, and R1234yf is 100 mass % are within the range of a figure surrounded by line segments QR, RT, TL, LK, and KQ that connect the following 5 points:   
       point Q (44.6, 23.0, 32.4), 
       point R (25.5, 36.8, 37.7), 
       point T (8.6, 51.6, 39.8), 
       point L (28.9, 51.7, 19.4), and 
       point K (35.6, 36.8, 27.6), 
       or on these line segments;
 the line segment QR is represented by coordinates (0.0099y 2 −1.975y+84.765, y, −0.0099y 2 +0.975y+15.235); 
 the line segment RT is represented by coordinates (0.0082y 2 −1.8683y+83.126, y, −0.0082y 2 +0.8683y+16.874); 
 the line segment LK is represented by coordinates (0.0049y 2 −0.8842y+61.488, y, −0.0049y 2 −0.1158y+38.512); 
 the line segment KQ is represented by coordinates (0.0095y 2 −1.2222y+67.676, y, −0.0095y 2 +0.2222y+32.324); and 
 the line segment TL is a straight line. 
 
     
     
         13 . The air conditioner according to  claim 1 ,
 wherein   the refrigerant comprises HFO-1132(E), R32, and R1234yf, wherein   when the mass % of HFO-1132(E), R32, and R1234yf based on their sum in the refrigerant is respectively represented by x, y, and z, coordinates (x,y,z) in a ternary composition diagram in which the sum of HFO-1132(E), R32, and R1234yf is 100 mass % are within the range of a figure surrounded by line segments PS, ST, and TP that connect the following 3 points:   
       point P (20.5, 51.7, 27.8), 
       point S (21.9, 39.7, 38.4), and 
       point T (8.6, 51.6, 39.8), 
       or on these line segments;
 the line segment PS is represented by coordinates (0.0064y 2 −0.7103y+40.1, y, −0.0064y 2 −0.2897y+59.9); 
 the line segment ST is represented by coordinates (0.0082y 2 −1.8683y+83.126, y, −0.0082y 2 +0.8683y+16.874); and 
 the line segment TP is a straight line.