Integrated motor-compressor unit having a cooling circuit and a depressurization system configured to reduce pressure of the cooling fluid

Abstract

An integrated motor-compressor unit comprising a motor and a compressor coupled to said motor via a rotatable shaft and mounted in a single common housing configured to circulate a cooling fluid in a cooling circuit, wherein the integrated motor-compressor unit comprises a depressurization system configured to depressurize the pressure of the motor.

1 - 14 . (canceled) 
     
     
         15 . A depressurization system for an integrated motor-compressor unit having a motor and a compressor coupled to said motor, wherein the depressurization system is configured to depressurize the motor, said system comprising an expansion device and an auxiliary compressor configured to recover the suction pressure, wherein the expansion device is a cooling expansion valve configured to receive the working fluid via a main compressor suction inlet of the compressor and to transmit expanded cooled fluid to a cooling circuit of the integrated motor-compressor unit, and wherein the auxiliary compressor is configured to receive the cooling fluid after having cooled notably the motor and to compress the cooling fluid. 
     
     
         16 . The depressurization system according to  claim 15 , wherein the expansion device is an expansion wheel. 
     
     
         17 . The depressurization system according to  claim 16 , wherein the depressurization system further comprises a cooler. 
     
     
         18 . The depressurization system according to  claim 15 , wherein the depressurization system further comprises a blower device. 
     
     
         19 . The depressurization system according to  claim 18 , wherein the depressurization system further comprises a depressurization auxiliary compressor configured to compensate for the compressor gas leakages. 
     
     
         20 . An integrated motor-compressor unit having a motor and a compressor coupled to said motor via a rotatable shaft and mounted in a single common housing configured to circulate a cooling circuit, wherein the integrated motor-compressor unit comprises a depressurization system configured to depressurize the pressure of the motor, said system comprising an expansion device and an auxiliary compressor configured to recover the suction pressure, wherein the expansion device is a cooling expansion valve configured to receive the working fluid via a main compressor suction inlet of the compressor and to transmit expanded cooled fluid to a cooling circuit of the integrated motor-compressor unit, and wherein the auxiliary compressor is configured to receive the cooling fluid after having cooled notably the motor and to compress the cooling fluid. 
     
     
         21 . The integrated motor-compressor unit according to  claim 20 , wherein the expansion device is an expansion wheel. 
     
     
         22 . The integrated motor-compressor unit according to  claim 21 , wherein the expansion wheel is mounted on the motor shaft end and the auxiliary compressor is mounted on the compressor shaft end. 
     
     
         23 . The integrated motor-compressor unit according to  claim 20 , wherein the expansion of the working fluid is created by voluntary compressor leakages that are compressed by the auxiliary compressor. 
     
     
         24 . The integrated motor-compressor unit according to  claim 23 , wherein the depressurization system also comprises a cooler mounted on the cooling circuit. 
     
     
         25 . The integrated motor-compressor unit according to  claim 20 , wherein the depressurization system comprises a blower device mounted upstream the compressor and configured to circulate the cooling fluid in a closed loop cooling circuit. 
     
     
         26 . The integrated motor-compressor unit according to  claim 25 , wherein the depressurization system further comprises a depressurization auxiliary compressor configured to compensate for the compressor gas leakages. 
     
     
         27 . The integrated motor-compressor unit according to  claim 25 , wherein the depressurization system also comprises a cooler mounted on the cooling circuit after or before the blower device. 
     
     
         28 . The integrated motor-compressor unit according to  claim 20 , wherein the rotatable shaft is supported at each end by at least one bearing.