Systems for cooling motors for gas compression applications

Abstract

A gas compression system that includes an electric motor that drives a compressor, a gas treatment device, and a gas cooling device. The electric motor may be cooled by a circulating flow of gas that is cooled by the gas cooling device and had been treated by the gas treatment device. The gas compression system may further include a gas feed that provides a supply of raw gas and a valve connected to the gas feed that controls a flow of raw gas from the gas feed to the gas treatment device. The valve may control the flow of raw gas from the gas feed to the gas treatment device such that any of the circulating flow of gas that is lost due to leakage is replaced. The gas treatment device may remove corrosive or abrasive impurities from the supply of raw gas.

1 . A gas compression system comprising:
 an electric motor that drives a compressor;   a gas treatment device; and   a gas cooling device;   wherein the electric motor is cooled by a circulating flow of gas that is cooled by the gas cooling device and had been treated by the gas treatment device.   
   
   
       2 . The gas compression system of  claim 1 , further comprising a gas feed that provides a supply of raw gas and a valve connected to the gas feed that controls a flow of raw gas from the gas feed to the gas treatment device. 
   
   
       3 . The gas compression system of  claim 2 , wherein the valve controls the flow of raw gas from the gas feed to the gas treatment device such that any of the circulating flow of gas that is lost due to leakage is replaced. 
   
   
       4 . The gas compression system of  claim 2 , wherein the gas treatment device removes corrosive or abrasive impurities from the supply of raw gas. 
   
   
       5 . The gas compression system of  claim 1 , further comprising a cooling gas compressor that is driven by the electric motor;
 wherein the cooling gas compressor compresses the circulating flow of gas before the circulating flow of gas passes through the electric motor.   
   
   
       6 . The gas compression system of  claim 5 , wherein the electric motor and the compressor are located within a motor-compressor casing;
 the electric motor and the cooling gas compressor are located within a internal casing, the internal casing being located within the motor-compressor casing; and   the internal casing is sealed within the motor-compressor casing by a plurality of internal seals.   
   
   
       7 . The gas compression system of  claim 6 , wherein the internal seals withstand the pressure differential between the pressure maintained within the internal casing and pressure maintained between the internal casing and the compressor-motor casing. 
   
   
       8 . The gas compression system of  claim 6 , wherein any of the circulating flow of gas that leaks from the internal casing is directed by a maintained pressure differential to the compressor for compression. 
   
   
       9 . The gas compression system of  claim 1 , wherein the electric motor comprises a high-speed electric motor. 
   
   
       10 . The gas compression system of  claim 5 , wherein a drive train of the compressor, the electric motor, and cooling gas compressor comprises a single shaft or common multi-piece shaft. 
   
   
       11 . The gas compression system of  claim 5 , wherein the circulating flow of gas comprises a flow that circulates from the cooling gas compressor to the electric motor, through the electric motor to the gas cooling device, through the gas cooling device to the cooling gas compressor, then through the cooling gas compressor to begin the circulation again. 
   
   
       12 . A gas compression system comprising:
 an electric motor that drives a compressor; and   a gas treatment device;   wherein the electric motor is cooled by a flow of cooling gas that is treated by the gas treatment device.   
   
   
       13 . The gas compression system of  claim 12 , further comprising a gas feed that provides a supply of raw gas from which the flow of cooling gas is taken;
 wherein the flow of cooling gas is directed through the electric motors and, after the flow of cooling gas passes through the electric motor, the flow of cooling gas is returned to the supply of raw gas, which then is directed to the compressor.   
   
   
       14 . The gas compression system of  claim 13 , further comprising a valve connected to the gas feed that controls the flow of cooling gas from the gas feed to the gas treatment device;
 wherein the valve controls the flow of cooling gas such that there is a flow rate available to adequately cool the electric motor.   
   
   
       15 . The gas compression system of  claim 12 , wherein the gas treatment device removes corrosive or abrasive impurities from the flow of cooling gas and the electric motor comprises a high-speed electric motor. 
   
   
       16 . The gas compression system of  claim 12 , further comprising a cooling gas compressor that is driven by the electric motor. 
   
   
       17 . The gas compression system of  claim 16 , wherein the flow of cooling gas is directed from the gas treatment device to the cooling gas compressor where the flow of cooling gas is compressed before it passes through the electric motor. 
   
   
       18 . The gas compression system of  claim 16 , wherein a drive train of the compressor, the electric motor, and cooling gas compressor comprises a single shaft or common multi-piece shaft. 
   
   
       19 . The gas compression system of  claim 12 , further comprising a treated gas bypass;
 wherein the treated gas bypass enables the flow of cooling gas that is directed to the electric motor to bypass the gas treatment device when desired.   
   
   
       20 . The gas compression system of  claim 19 , wherein the supply of raw gas contains a level of corrosive or abrasive impurities; and
 the flow of cooling gas bypasses the gas treatment device when it is determined that the level of corrosive or abrasive impurities in the supply of raw gas is below a predetermined level.