Abstract:
The present disclosure relates to a turbo compression system having two or more driving motors provided with a motor-cooling system for efficiently cooling two or more driving motors in the gearless type turbo compressor. An aspect of a turbo compression system having two or more driving motors according to the present disclosure comprises a first, second and third impeller provided separately; two or more driving motor rotating at least one among the first, second and third impeller; and a cooling impeller provided unitarily and simultaneously cooling the two or more driving motor. On the other hand, the turbo compression system having two or more driving motors further may comprise a fan motor rotating the cooling impeller and provided separately from the two or more driving motor.

Description:
TECHNICAL FIELD 
       [0001]    The present disclosure relates to a turbo compression system having two or more driving motors, in detail, the turbo compression system having a motor-cooling system for efficiently cooling two or more driving motors in the gearless type turbo compressor. 
       BACKGROUND 
       [0002]    This section provides background information related to the present disclosure which is not necessarily prior art. 
         [0003]    Generally, a conventional turbo compressor is a device for compressing gases such as air or refrigerant. The conventional turbo compressor is characterized in that the discharge pressure thereof is very high. 
         [0004]    U.S. Pat. No. 6,398,517 discloses a two-stage turbo compression system having gearless type turbo compressor and U.S. Pat. No. 7,044,718 discloses a three-stage turbo compression system having two turbo compressor which not only accomplishes three-stage compression by using two high-speed driving motors but also improves the compression efficiency by first-stage impeller coupled with the first driving motor and second-stage and third-stage impellers coupled with the second driving motor. 
         [0005]    In the conventional turbo compression system, cooling system which cools high-speed driving motor has been installed and the three-stage turbo compression system having turbo compressor is equipped with two or more cooling impellers. That is, two or more cooling impellers, being respectively connected to separate cooling motors and rotating, may discharge heat out of the first and second driving motor which compress gases. 
         [0006]    However, the conventional cooling system for the three-stage turbo compression system needs to be equipped with additional two or more cooling impellers and cooling motors for rotational driving of the cooling impellers. It caused some problems of making the structure of cooling system complicated, increasing product cost, and having space restraints for installing. 
         [0007]    Meanwhile, in addition to that, it was disclosed that the system cools the driving motor by using some of compressed gases so as to improve cooling efficiency of the driving motor. But it also caused a problem of decrease of overall efficiency of turbo compression system. 
       SUMMARY 
       [0008]    An object of the present disclosure is to provide a turbo compression system having two or more driving motors of which the excellent cooling efficiency may be maintained, and of which the configuration is simple. 
         [0009]    An aspect of a turbo compression system having two or more driving motors according to the present disclosure comprises a first, second and third impeller provided separately; two or more driving motor rotating at least one among the first, second and third impeller; and a cooling impeller provided unitarily and simultaneously cooling the two or more driving motor. 
         [0010]    The cooling impeller may be connected to a rotation shaft of one of the two or more driving motor and rotates. 
         [0011]    The cooling impeller may be direct-connected to a rotation shaft of one of the two or more driving motor. 
         [0012]    The cooling impeller may be provided with an axial flow type impeller. 
         [0013]    The turbo compression system having two or more driving motors further may comprise a fan motor rotating the cooling impeller and provided separately from the two or more driving motor. 
         [0014]    The two or more driving motor may include a first motor connecting with the first impeller and the second impeller at both sides of the first motor, and a second motor connecting with the third impeller at its one side and connecting with the cooling impeller at its the other side. 
         [0015]    The turbo compression system having two or more driving motors further may comprise a cooling flow path connecting into the cooling impeller after passing through one and the other of the first motor and the second motor in sequence. 
         [0016]    The turbo compression system having two or more driving motors further may comprise a cooling flow path passing through the first motor and the second motor separately, joining and then connecting into the cooling impeller. 
         [0017]    The turbo compression system having two or more driving motors further may comprise the two or more driving motor including a first motor connecting with the first impeller and the second impeller at both sides of the first motor, and a second motor connecting with the third impeller at its one side; and a cooling flow path connecting into the cooling impeller after passing through one and the other of the first motor and the second motor in sequence. 
         [0018]    The cooling impeller may be provided with an axial flow type impeller. 
         [0019]    An aspect of a turbo compression system having two or more driving motors according to the present disclosure may have advantage to maintain the excellent cooling efficiency of the cooling system for cooling the two or more driving motors. 
         [0020]    An aspect of a turbo compression system having two or more driving motors according to the present disclosure may also have advantage to make the structure of the cooling system simple and compact, to solve space restraints for installing, and to decrease the product cost of the cooling system. 
     
    
     
       DRAWINGS 
         [0021]      FIG. 1  is a view showing a turbo compression system having two or more driving motors according to the first embodiment of the present disclosure, 
           [0022]      FIG. 2  is a view showing a turbo compression system having two or more driving motors according to the second embodiment of the present disclosure, and 
           [0023]      FIG. 3  is a view showing a turbo compression system having two or more driving motors according to the third embodiment of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0024]    Hereinafter, various embodiments of a turbo compression system according to the present disclosure will be described with reference to the accompanying drawings. 
         [0025]      FIG. 1  is a view showing a turbo compression system having two or more driving motors according to the first embodiment of the present disclosure. 
         [0026]    Referring to  FIG. 1 , a turbo compression system having two or more driving motors according to the first embodiment of the present disclosure comprises a first impeller  10 , a second impeller  20 , a third impeller  30 , driving motors including a first motor  40  and a second motor  50 , and a cooling impeller  60 . 
         [0027]    The first impeller  10  is connected to the rotation shaft  41  arranged at one side of the first motor  40  and rotates, and the second impeller  20  is connected to the rotation shaft  42  arranged at the other side of the first motor  40  and rotates. 
         [0028]    In this case, an intercooler may be installed between the first impeller  10  and the second impeller  20 . 
         [0029]    Furthermore, the third impeller  20  is connected to the rotation shaft  51  arranged at one side of the second motor  50  and rotates. 
         [0030]    Gas flowing in the first impeller  10  is compressed and discharged through the third impeller  30  passing through the second impeller  20 . 
         [0031]    The cooling impeller  60  is connected to the rotation shaft  52  arranged at the other side of the second motor  50  and rotates. In this case, the cooling impeller  60  rotates coaxially with the third impeller  30  connected to the second motor  50 . Therefore, any separate driving device for the cooling impeller  60  is not needed by connecting the cooling impeller  60  to the rotation shaft  52  arranged at the other side of the second motor  50 . Therefore it may decrease the product cost of the cooling system. 
         [0032]    Furthermore, since the rotating velocity of the cooling impeller  60  is adjustable dependent on the rotating velocity of the second motor  50 , any inverter for adjusting the rotating velocity of the cooling impeller  60  is not needed additionally. Therefore it may decrease the product cost of the cooling system and furthermore it may save the energy in partial-load operation. 
         [0033]    In this case, the cooling impeller  60  is desirable to be provided with an axial flow type impeller because the rotating velocity of the second motor  50  is very high. 
         [0034]    Meanwhile, since the first impeller  10  and the second impeller  20  are connected together with the first motor  40 , the turbo compression system according to the present embodiment can be used as a low pressure compression system in itself and also the productivity can be increased. 
         [0035]    Additionally, a turbo compression system having two or more driving motors according to the first embodiment of the present disclosure can cool plural driving motor by using one cooling impeller  60 . 
         [0036]    That is, a cooling flow path  70  is provided so as to communicate the first motor  40  with the second motor  50  and the cooling impeller  60  activates the forced circulation flow of cooling air into the cooling flow path  70 . 
         [0037]    Therefore, cooling air flowing in one side of the cooling flow path  70  cools the first motor  40  passing through the first motor  40 , and then cooling air is discharged outside through the cooling impeller  60  after passing through the cooling flow path  70  and cooling the second motor  50  in sequence. 
         [0038]      FIG. 2  is a view showing a turbo compression system having two or more driving motors according to the second embodiment of the present disclosure. 
         [0039]    Referring to  FIG. 2 , the three-stage turbo compression system according to the second embodiment of the present disclosure comprises a first impeller  10 , a second impeller  20 , a third impeller  30 , driving motors including a first motor  40  and a second motor  50 , and a cooling impeller  60 . 
         [0040]    The first impeller  10  is connected to the rotation shaft  41  arranged at one side of the first motor  40  and rotates, the second impeller  20  is connected to the rotation shaft  51  arranged at one side of the second motor  50  and rotates, and the third impeller  30  is connected to the rotation shaft  52  arranged at the other side of the second motor  50  and rotates. In this case, an intercooler may be installed between the second impeller  20  and the third impeller  30 . 
         [0041]    Gas flowing in the first impeller  10  is compressed and discharged through the third impeller  30  passing through the second impeller  20 . In this case, an additional intercooler may be installed between the first impeller  10  and the second impeller  20 . 
         [0042]    The cooling impeller  60  is connected to the rotation shaft  42  arranged at the other side of the first motor  40  and rotates. In this case, the cooling impeller  60  rotates coaxially with the first impeller  10  connected to the first motor  40 . 
         [0043]    Therefore, any separate driving device for the cooling impeller  60  is not needed by connecting the cooling impeller  60  to the rotation shaft  42  arranged at the other side of the first motor  40 . Therefore it may decrease the product cost of the cooling system. 
         [0044]    Furthermore, since the rotating velocity of the cooling impeller  60  is adjustable dependent on the rotating velocity of the first motor  40 , any inverter for adjusting the rotating velocity of the cooling impeller  60  is not needed additionally. Therefore it may decrease the product cost of the cooling system and furthermore it may save the energy in partial-load operation. 
         [0045]    In this case, the cooling impeller  60  is desirable to be provided with an axial flow type impeller because the rotating velocity of the first motor  40  is very high, and the cooling efficiency may get better in case the first impeller  10  and the cooling impeller  60  are provided together with the first motor  40  because the revolution per minute (RPM) of the first impeller is relatively low. 
         [0046]    Additionally, a turbo compression system having two or more driving motors according to the first embodiment of the present disclosure can cool plural driving motor by using one cooling impeller  60 . 
         [0047]    That is, a first intake flow path  71  is provided with the first motor  40  for the intake of cooling air and a second intake flow path  72  is provided with the second motor  50  for the intake of cooling air, and then the first intake flow path  71  and the second intake flow path  72  are joined and connected to a branch flow path  73  connected to the cooling impeller  60 . 
         [0048]    Therefore, cooling air flowing into the first motor  40  by the cooling impeller  60  is discharged outside through the cooling impeller  60  after passing through the first intake flow path  71  and the branch flow path  73  in sequence, and cooling air flowing into the second motor  50  by the cooling impeller  60  is discharged outside through the cooling impeller  60  after passing through the second intake flow path  72  and the branch flow path  73  in sequence. That is, cooling air flowing into one side of the first intake flow path  71  cools the first motor  40  and then is discharge outside, and cooling air flowing into one side of the second intake flow path  72  cools the second motor  50  and then is discharge outside. the cooling efficiency may get better due to the separate intake structure as above. 
         [0049]      FIG. 3  is a view showing a turbo compression system having two or more driving motors according to the third embodiment of the present disclosure. 
         [0050]    Referring to  FIG. 3 , the turbo compression system having two or more driving motors according to the third embodiment of the present disclosure further comprises a fan motor  80  for rotating the cooling impeller  60 , in addition to elements of the turbo compression system having two or more driving motors according to the first embodiment of the present disclosure as above-mentioned. Hereinafter, the explanation on the same elements as above mentioned will be omitted. 
         [0051]    In the present embodiment, the cooling impeller  60  is not connected to the driving motor but connected to the fan motor  80  provided separately so as not to have a bad effect on the performance of the turbo compressor and so as to decrease the product cost by cooling plural driving motor by using one cooling impeller  60 . 
         [0052]    The descriptions as above mentioned have been given by the way of an example in limited embodiments for a clear understanding of the technical idea disclosed. It is not limited thereto, but applicable to the embodiments which can be deduced by those who have conventional knowledge in the field of the art that belongs to the technical idea disclosed below, in advance.