EP2667035A2

EP2667035A2 - Temperature control system for a machine and methods of operating same

Info

Publication number: EP2667035A2
Application number: EP13168690.9A
Authority: EP
Inventors: Ilia Oxman; William Dwight Gerstler; Mark John Deblock; Jeremy Daniel Van Dam; Michael John Douglass; Olivier Pellerin
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 2012-05-23
Filing date: 2013-05-22
Publication date: 2013-11-27
Also published as: US20130315755A1; CN103423173A; JP2013245672A

Abstract

A temperature control system for an electrical machine and a method of operating the system is provided. The machine includes a housing 20 enclosing a motor 18 and a compressor 16, the housing includes a suction pipeline 28 in flow communication with the compressor. The suction pipeline 28 is configured to channel fluid into the housing 20. A temperature control system assembly includes a fluid mover 72 coupled to at least one of the rotor shaft 48 and the compressor shaft 58 and in flow communication with the suction pipeline upstream from the compressor. The fluid mover 72 is configured to channel the fluid from the suction pipeline and across at least one of the motor and the compressor. Temperature control system includes a distribution header coupled to the housing 20 and in flow communication with the fluid mover 72, the distribution header includes a first outlet coupled in flow communication to the motor to channel the fluid across the motor 18.

Description

The present disclosure relates to electrical machines and, more particularly, to methods and systems for use in temperature control of the electrical machine.
Electrical machines, such as integrated motor-driven compressors, generate heat during operation as a result of both electrical and mechanical losses. Components in both the motor and the compressor of the integrated motor-driven compressor require temperature control in order to maintain temperatures within allowable operating ranges. An excessively high motor temperature, for example, may result in motor bearing failure and/or damage to the stator winding insulation, power connectors, or instrumentation. Maintaining optimal temperature range for temperature sensitive components of electrical machines results in enhanced performance efficiency and extending service life.
Electrical drives may be advantageous over mechanical drives (i.e., gas turbines) in operational flexibility (attaining constant torque at variable speed for example), maintainability, lower capital cost and lower operational cost, better efficiency, and environmental compatibility. Additionally, electric drives are generally simpler in construction than mechanical drives, generally require a smaller foot print, may be easier to integrate with a temperature control system, may eliminate the need for a gearbox, and/or may be more energy efficient and reliable than mechanical drives.
At least some known electrical machines use temperature control systems that include separate cooling systems for both the motor and the compressor. However, multiple cooling systems may increase manufacturing, installation, operation, and/or maintenance costs. Further, within at least some known electric drives, compressor and drive components are cooled using high pressure gas bled from the compressor. However, bleeding significant flow of partly or fully compressed gas from the compressor to provide for motor cooling needs reduces compression efficiency and may also cause additional stress, vibration, and fatigue of the compressor components. In some cases, the pressure of the fluid available from the compressor is far higher than the pressure required for cooling flow and must be throttled, which represents an efficiency loss. Further, in some cases, the fluid being transported may have aggressive constituents or impurities entrained therein that may adversely affect service life of the components being used.
In one aspect, an electrical machine is provided. The electrical machine includes a motor having a stator, a rotor, and a rotor shaft, wherein a compressor is rotatably coupled to the motor and includes a compressor shaft. The machine further includes a housing enclosing the motor and the compressor, wherein the housing includes a suction pipeline in flow communication with the compressor. The suction pipeline is configured to channel fluid into the housing. A temperature control system assembly is coupled in flow communication to the housing. The temperature control system assembly includes a fluid mover coupled to at least one of the rotor shaft and the compressor shaft and in flow communication with the suction pipeline upstream from the compressor. The fluid mover is configured to channel the fluid from the suction pipeline and across at least one of the motor and the compressor. The temperature control system further includes a distribution header coupled to the housing and in flow communication with the fluid mover, wherein the distribution header includes a first outlet coupled in flow communication to the motor to channel the fluid across the motor.
In another aspect, a temperature control system for use in cooling an electrical machine. The system includes a housing having a motor portion, and a compressor portion, wherein the motor portion and the compressor portion are configured in flow communication. The system further includes a temperature control system coupled to the housing and includes an inlet coupled to the motor portion and includes a distribution header coupled to the motor portion and the compressor portion. A fluid mover is coupled to the motor portion and configured to channel a fluid from the inlet and within the motor portion and the distribution header.
In a further aspect, a method of operating an electrical machine having a motor, a compressor and a suction pipeline is provided. The method includes moving a fluid from the suction pipeline and into a housing having a motor portion disposed about the motor and a compressor portion disposed about the compressor. The fluid is moved within the motor portion and across the motor and within the compressor portion and across the compressor. The method includes moving the fluid within a distribution header in flow communication with the motor portion and the compressor portion, and then discharging the fluid from the housing.

Fig. 1 is a cross-sectional schematic view of an exemplary temperature control system that may be used with an electrical machine.
Fig. 2 is a cross-sectional schematic view of an alternative temperature control system that may be used with an electrical machine.
Fig. 3 is a cross-sectional schematic view of an alternative temperature control system that may be used with an electrical machine.
Fig. 4 is a cross-sectional schematic view of an alternative temperature control system that may be used with an electrical machine.
Fig. 5 is a cross-sectional schematic view of an alternative temperature control system that may be used with an electrical machine.
Fig. 6 is a flowchart of an exemplary method of operating a temperature control system in an integrated motor-compressor electrical machine.
Fig. 1 is a cross-sectional schematic view of an exemplary temperature control system 10 for use with an electrical machine 12. In the exemplary embodiment, machine 12 includes an integrated motor-compressor assembly 14. Temperature control system 10 facilitates temperature control, such as cooling and/or heating, for temperature-sensitive components of assembly 14. In the exemplary embodiment, machine 12 includes a multi-stage compressor 16 that is rotatably coupled to an electric drive motor 18.

Temperature control system 10 includes a single common housing 20 that encloses motor 18, compressor 16, forming a leak-tight pressure vessel. In the exemplary embodiment, static components of motor 18 and compressor 16 are fixedly coupled within housing 20. Motor 18 is positioned within a motor portion 22 of housing 20 and compressor 16 is positioned within a compressor portion 24 of housing 20. Housing 20 includes a compressor suction port 26 that is coupled in flow communication to compressor portion 24. Compressor suction port 26 is also coupled to an inlet suction pipeline 28 that is coupled to a fluid source 29 containing compressible fluid 30 at an initial pressure. Fluid source 29 includes structures such as, but not limited to, storage tanks, process or distribution pipelines, natural gas wells, etc. Fluid 30 includes a medium such as, but not limited to, gas, air and various other compressible gaseous media. In the exemplary embodiment, fluid 30 includes a mixture of flammable gases termed "natural gas". Fluid 30 may be obtained directly from various mineral resources or produced by an engineered, biological or chemical process.
In the exemplary embodiment, temperature control system 10 also includes a compressor end piece 32 that is coupled to housing 20. End piece 32 facilitates enclosing compressor 16 within assembly 14 subsequent to insertion of compressor 16 into housing 20 and includes a compressor discharge outlet 34 that is coupled in flow communication to a compressor outlet pipeline 36. Compressor outlet pipeline 36 may couple to other systems (not shown) and/or to fluid source 29. In addition, a motor end cover 38 is coupled to housing 20. End cover 38 facilitates enclosing motor 18 within assembly 14 subsequent to insertion of motor 18 into housing 20. As illustrated, housing 20 encloses motor 18 and compressor 16 to define an interior 40 that facilitates flow communication within and between motor portion 22 and compressor portion 24. In this embodiment, housing 20 can be constructed with one or both of the side covers 32 and 38 which are removable, for convenient assembly and maintenance. Alternatively, housing 20 may include other constructions (not shown) such as, but not limited to, a construction with a horizontal split.
Motor 16 includes a rotor 42 fabricated from magnetically conductive materials, a plurality of permanent magnets (not shown) that are coupled to rotor 42, and a stator 44 that are positioned such that a gap 46 is defined between rotor 42 and stator 44. The permanent magnets induce a magnetic field around rotor 42. When stator 44 is powered, an electromagnetic field is induced within motor 16. Gap 46 facilitates magnetic coupling of rotor 42 and stator 44 to generate a torque that induces rotation in rotor 42. Alternatively, motor 16 may include any configuration that provides for an electro-magnetic coupling between rotor 42 and stator 44.
A shaft 48 extends through rotor 42, and defines a motor axis of rotation 50. Motor axis 50 may be a center axis for housing 20, rotor 42, and stator 44. Shaft 48 may be fixed to rotor 42 such that as rotor 42 rotates, rotor 42 drives shaft 48. Likewise, when shaft 48 rotates, shaft 48 may drive rotor 42. Bearings 52 support shaft 48 within housing 20. In the exemplary embodiment, bearings 52 include an opposite drive end motor bearing 54 and a drive end motor bearing 56. Alternatively, bearings 52 (not shown) may be housed in separate enclosures to facilitate replacement without interference with other components at system 10.
Compressor 16 includes a rotatable compressor shaft 58 that is coupled to rotor 42. In the exemplary embodiment, a shaft coupler 60 is configured to rotatably couple rotor shaft 48 to compressor shaft 58. Coupler 60 includes a rotating coupling element (not shown). Coupler 60 may include any mechanical contact coupling (not shown) or non-contacting electro-magnetic coupling (not shown). Alternatively, rotor shaft 48 and compressor shaft 58 may be integral (not shown) and free from any coupling element. Rotor shaft 48 and compressor shaft 58 are rotatable about motor axis of rotation 50. In the exemplary embodiment, compressor 16 includes a plurality of compressor stages 62. Alternatively, compressor 16 may include only one stage (not shown). Compressor shaft 58 is supported by radial bearings 64 and 66, and an axial bearing 68. Location of the radial bearings 64 and 66 and thrust bearing 68 within compressor portion 24 may vary depending on design requirements; wherein bearings 64, 66, or 68 may be located opposite of the compressor portion 24 and enclosed in their own separate housings (not shown).
In the exemplary embodiment, temperature control system 10 includes a temperature control assembly 70 and a fluid mover 72. Temperature control assembly 70 includes a supply pipeline 76, a return pipeline 78 and a distribution header 80 coupled to housing 20 and in flow communication with supply pipeline 76 and return pipeline 78. As illustrated in Figure 1, motor 18 with its associated shaft 48 and bearings 54 and 56, shaft coupler 60 and compressor 16 with its associated shaft 58 and bearings 64, 66 and 68, are in flow communication with distribution header 80.
Supply pipeline 76, return pipeline 78 and distribution header 80 are coupled to housing 20 and in flow communication with interior 40 of housing 20. More particularly, supply pipeline 76 is coupled in flow communication with inlet suction pipeline 28 and motor end cover 38. More particularly, supply pipeline 76 is coupled in flow communication with inlet suction pipeline 28 upstream from suction port 26 Return pipeline 78 is coupled in flow communication to housing 20 and inlet suction pipeline 28. Connection of return pipeline 78 to inlet suction pipeline 28 is downstream of the connection point of supply pipeline 76 to inlet suction pipeline 28. Pipelines 76 and 78 may be fabricated of metal, rubber, polyvinylchloride (PVC), or any material that attains predetermined operational parameters associated with fluid 30 being transported and the location of assembly 14. Pipelines 76 and 78 are sized to facilitate initial filling, and subsequently facilitate maintaining fluid pressure within housing 20 at pre-determined operating pressures.
In the exemplary embodiment, supply pipeline 76 includes a flow control device 82 such as, but not limited to, a regulating valve, for example, a throttling-type valve that is adjusted to predetermined open positions to facilitate channeling a predetermined flow of fluid 30 from fluid source 29 and through housing 20 as well as a predetermined rate of pressurization of housing 20. Flow control device 82 may be, but not be limited to, a needle valve. Other types of regulating valves may also be used that enables functionality of the temperature control system 10 as described herein. Moreover, flow control device 82 may include flow control orifices.
Motor end cover 38 includes a fluid supply passage 84 defined within motor end cover 38 that is coupled in flow communication with supply pipeline 76. Fluid supply passage 84 is sized to facilitate initial filling of, and subsequently facilitate maintaining fluid pressure within housing 20 at pre-determined operating pressures. Passage 84 also facilitates creating optimal inlet flow pattern for fluid mover 72 and controlling a rate of pressurization of housing 20 to a predetermined rate.
Return pipeline 78 includes a motor return pipeline section 86 and a compressor return pipeline section 88. Motor return pipeline section 86 is coupled in flow communication to motor portion 22 and to inlet suction pipeline 28. Motor return pipeline section 86 includes a flow control device 90 located between housing 20 and inlet suction pipeline 28. Compressor return pipeline section 88 is coupled in flow communication to compressor portion 24 and inlet suction pipeline 28. Compressor return pipeline section 88 includes a flow control device 92 located between housing 20 and inlet suction pipeline 28. Motor return pipeline 86 and compressor return pipeline 88 are coupled to suction pipeline 28 downstream of supply pipeline 76 and upstream from suction port 26. The return flow of fluid 30 through motor return pipeline 86 and compressor return pipeline 88 can be mixed with fluid 30 within inlet suction pipeline 28 to facilitate closed temperature operations for control system 10.
Distribution header 80 includes a first outlet 94, a second outlet 96, and a distribution channel 98 between first outlet 94 and second outlet 96. Alternatively, distribution header 80 may have a single outlet or more than three outlets in flow communication with housing 20. In the exemplary embodiment, distribution header 80 is configured external of housing 20. Alternatively, distribution header 80 can be positioned within housing 20. More particularly, distribution header 80 can be positioned within at least one of motor portion 22 and compressor portion 24.
First outlet 94 is coupled to housing 20 and in flow communication with motor portion 22. More particularly, first outlet 94 is in flow communication with motor portion 22 adjacent shaft coupler 60. Distribution header 80 includes a flow control device 100 located between first outlet 94 and distribution channel 98. Second outlet 96 is coupled to housing 20 and in flow communication with compressor portion 24. Second outlet 96 is flow communication with compressor portion 24 adjacent opposite drive end compressor bearing 64. Distribution header 80 further includes a flow control device 102 located between second outlet 96 and distribution channel 98. Flow control devices 82, 90, 92, 100, 102 may be manually and/or electronically controlled. In the exemplary embodiment, a controller 104 is coupled to flow control devices via control circuits 106 to facilitate electronic operation of flow control devices. For simplicity, Fig. 1 illustrates control circuit 106 coupling flow control device 92 to controller 104. Any type of controller 104 such as, but not limited to, a central processing unit or microprocessor may be used that enables temperature control system 10 and electrical machine 12 to function as described herein.
Fluid mover 72 is coupled to at least one of rotor shaft 48 and compressor shaft 58. In the exemplary embodiment, fluid mover 72 is a fan coupled to an opposite drive end portion of motor shaft 48 to rotate with rotor shaft 48. Fluid mover 72 is dimensioned and positioned to facilitate fluid flow from suction pipeline 28, through supply pipeline 76 and within housing 20, motor portion 22, and compressor portion 24 to facilitate temperature control of temperature sensitive components therein. Moreover, fluid mover 72 is dimensioned and positioned to facilitate fluid flow within distribution header 80. Alternatively, fluid mover 72 may include, but not be limited to, a pump or compressor or any device that attains predetermined parameters associated with fluid 30 being transported within housing 20. Moreover, fluid mover 72 may be positioned within interior 40 of housing 20 wherever predetermined operational parameters are attained. In an alternative embodiment (not shown), fluid mover 72 is coupled to compressor shaft 58. Using a low compression ratio fluid mover 72 to facilitate fluid flow across compressor 16 and motor 18 is more economical than diverting a portion of high pressure gas obtained inside or downstream of known compressors (not shown) for temperature control of compressor components.
In operation, fluid 30 being transported by temperature control system 10 is used to facilitate temperature control of at least motor 18, coupler 60, and compressor 16 along with associated shafts 48 and 58 and bearings 54, 56 and 64, 66 and 68 as illustrated with arrows in Fig. 1. Prior to electrically powering stator 44 and starting motor 18, housing 20 is filled with fluid 30 and attains a pressure substantially similar to that of inlet suction pipeline 28. Moreover, motor portion 22 and compressor portion 24 are filled with fluid 30 and are also in substantial pressure equilibrium.
During operation, a power source (not shown) supplies multi-phase alternating current to stator 44 at pre-determined voltages and frequencies. A rotating electromagnetic field is generated in stator 44. At any given speed, a relative strength of the magnetic field generated is proportional to the voltage supplied by power source. As the electromagnetic field induced in stator 44 rotates, the magnetic field of rotor 42 interacts with the electromagnetic field of stator 44 through gap 46. The interaction of the two magnetic fields induces torque, and subsequently, rotation of rotor 42 and rotor shaft 48. Compressor shaft 58 is rotated via coupler 60 to power compressor 16.
Fluid 30 is channeled from fluid source 29 and into inlet suction pipeline 28 due to low suction pressure created in the compressor inlet 26 as a result of rotation of rotor 42 and/or rotor shaft 48. A portion of fluid 30 is channeled into compressor 16, where its pressure is increased to a required value. During process of compression in compressor 16, fluid 30 is heated. Heated fluid 30 from compressor 16 is discharged through compressor discharge outlet 34 and through compressor outlet pipeline 36. Discharged fluid 30 from compressor outlet pipeline 36 can be re-circulated with fluid source 29.
In operation, a portion of fluid 30 is channeled from inlet suction pipeline 28, through supply pipeline 76 and towards motor end cover 38 as the associated arrows illustrate. Fluid 30 is channeled through motor portion 22, compressor portion 24, and distribution header 80, and subsequently channeled to suction port 26 via return pipeline 78. More particularly, once motor 18 is powered and rotor 42 is rotating, fluid mover 72 forms a low pressure region locally in the vicinity of the region wherein passage 84 couples in flow communication to motor portion 22 and also forms a local high pressure region within motor portion 22. Fluid 30 is channeled by fluid mover 72 from inlet suction pipeline 28, through supply pipeline 76, and into passage 84. The fluid 30 is further channeled within motor portion 22 and across opposite motor drive end bearing 54, motor 18, and motor drive end bearing 56. As fluid 30 is channeled through motor portion 22, fluid 30 removes heat from motor 18 and bearings 56 and 58. Heated fluid 30 from motor portion 22 is discharged through motor return pipeline 86, where heated fluid 30 is mixed with fluid 30 in inlet suction pipeline 28.
A portion of fluid 30 that is moved by fluid mover 72 is channeled into distribution header 80 and through at least one first outlet 94 and second outlet 96. A portion of fluid 30 flows from header 80, through first outlet 94 and within motor portion 22. More particularly, a portion of fluid 30 flows across coupler 60, motor drive end bearing 56, and opposite drive end compressor bearing 66. As fluid 30 is channeled through first outlet 94, fluid removes heat from coupler 60 and motor bearing 56 and compressor bearing 66. Portions of fluid 30 from housing 20, which houses coupler 60, is directed through bearings 56 and then is channeled through motor return pipeline 86, where the heated fluid 30 is mixed with fluid 30 in inlet suction pipeline 28. Other portions of fluid 30 are channeled from shaft coupler 60 through the compressor bearing 66 and then mixed with suction flow of the compressor 16.
A portion of fluid 30 flows through header 80 and into second outlet 96, within compressor 16, and through the opposite drive end compressor bearing 64 and thrust bearing 68. As fluid 30 is channeled through second outlet 96, fluid 30 removes heat from bearings 64 and 68. Heated fluid 30 from bearings 64 and 68 is channeled through compressor return pipeline 88, where the heated fluid 30 is mixed with fluid 30 in inlet suction pipeline 28. Controller 104 and regulating flow control devices facilitate optimizing fluid supply to various areas of temperature control system 10 over a range of temperatures, rotating speeds, and motor loads.
During operation of temperature control system 10, fluid mover 72 is coupled to rotor shaft 48 and fluid 30 at low pressure is taken from inlet suction pipeline 28 upstream from compressor 16, wherein fluid pressure is then increased by fluid mover 72 and the flow of compressed cooling fluid 30 is directed to the various components in motor portion 22 and compressor portion 24 to facilitate simultaneously maintaining temperatures within a pre-determined range. Temperature control system 10 uses the same source of pressurized fluid and the same fluid source 29 for various sub-systems located in motor portion 22 and compressor portion 24, where the source of pressurized fluid, i.e., fluid mover 72 is coupled to rotor shaft 48. Cost reduction is achieved by using single temperature control system 10 for cooling motor portion 22 and compressor portion 24. Moreover, fluid heat-up prior to channeling fluid 30 after compression by fluid mover 72 is minimal, since any temperature rise in fluid mover 72 and fluid 30 that is channeled to distribution header 80 can be made acceptably small due to low compression ratio of fluid mover 72, such as a fan, and by design of the components in contact with fluid 30.
Temperature control system 10 can also be used for heating of motor portion 22 and/or compressor portion 24 when appropriate amount of heating fluid 30 is provided. For example, components of motor 18 and/or compressor 16 may require pre-heating prior to cold start of integrated motor-compressor assembly 14 and/or to perform diagnostic testing.
Fig. 2 is a cross-sectional schematic view of an alternative temperature control system 108. Moreover, in Fig. 2, the same reference numerals are used to indicate identical components previously described. Motor 18 further includes at least one magnetic bearing 56 coupled to motor rotor shaft 48 to support rotor shaft 48. Compressor 16 also includes at least one magnetic bearing 66 coupled to compressor shaft 58 to support compressor shaft 58. Magnetic bearing 56 is sealed from the motor inner space with a seal 110 and magnetic bearing 66 is sealed from the compressor inner space with a seal 112. In the exemplary, seals 110 and 112 include non-contact labyrinth seals 130 to facilitate operation of bearings 56 and 66.
Magnetic bearings 56 and 66 facilitate radial positioning of motor rotor shaft 48 and compressor shaft 58. In the exemplary embodiment, magnetic bearings 56 and 66 are configured to be an active-type of magnetic bearing. More specifically, a control subsystem (not shown) is used in conjunction with magnetic bearings 56 and 66 to determine the radial position of the rotational bearing component (not shown) relative to the fixed component (not shown) at any given time, and facilitate magnetic adjustments to correct any deviations at any given angular position. Magnetic bearings 56 and 66 facilitate operation of motor rotor shaft 48 and compressor shaft 58 at the high speeds associated with exemplary motor 18 and compressor 16. Alternatively, non-magnetic bearings (not shown) may be used that include, but not be limited to including, roller bearings, for example, that attain predetermined parameters, that include, but are not limited to, mitigating vibration and friction losses. At least one rundown bearing (not shown) may be positioned within motor 18 and/or compressor 16 to facilitate radial support to rotor shaft 48 and/or compressor shaft 58 in the event of magnetic bearing failure. Furthermore, at least one axial bearing 68 may be coupled to compressor 16 to facilitate mitigating the effects of axial thrust of motor shaft 48 and compressor shaft 58.
In the exemplary embodiment, first outlet 94 of distribution header 80 is in flow communication with a motor inlet 114 and outlet 95 of header 80 is in flow communication with a compressor inlet 116. Distribution header 80 further includes a flow control device 118 between motor inlet 114 and distribution channel 98, and includes a flow control device 120 between compressor inlet 116 and distribution channel 98. Moreover, return pipeline 78 includes a first return pipeline 122 and a second return pipeline 124 that are in flow communication with suction pipeline 28. In the exemplary embodiment, first return pipeline 122 includes a flow control device 126 between housing 20 and inlet suction pipeline 28, while second return pipeline 124 includes a flow control device 128 between housing 16 and inlet suction pipeline 28.
During operation, fluid 30 is channeled into and through distribution header 80 as previously described. A portion of fluid 30 is channeled through motor inlet 114 and into housing 20. More particularly, fluid 30 is channeled into housing 20 between magnetic bearing 56 and seal 110, fitted with non-contact labyrinth seal 130. Fluid 30 is channeled through and out of labyrinth seal 130 into housing 20 and across bearing 56 and coupler 60 to facilitate cooling of bearing 56 and coupler 60. Heated fluid 30, after passing through labyrinth 130, is mixed with heated fluid 30 from motor 18 and channeled out of housing 20 through the first return pipeline 122. Heated fluid 30 from bearing 56 and coupler 60 is channeled through second return pipeline 124, where heated fluid 30 is mixed with fluid 30 in inlet suction pipeline 28 and transferred to compressor suction port 26.
A portion of fluid 30 is channeled through outlet 95 of distribution header 80 to compressor inlet 116 and into housing 20. More particularly, fluid 30 is channeled into housing 20 between magnetic bearing 60 and seal 112, which is fitted with non-contact labyrinth seal 130. Fluid 30 is channeled through and out of labyrinth 130 into housing 20 and across bearing 66 and coupler 60 to facilitate cooling of bearing 66 and coupler 60. Heated fluid 30 from bearing 66 and coupler 60 is channeled through second return pipeline 124, where the heated fluid 30 is mixed with fluid in suction pipeline 28 and transferred to compressor suction port 26. During operation, flow control devices 118, 120 and 126, 128 are coupled to controller 104 through temperature control circuits 166 to facilitate regulating fluid flow rates.
Fig. 3 is a cross-sectional schematic view of an alternative fluid system 132. Moreover, in Fig. 3, the same reference numerals are used to indicate identical components previously described. Fluid system 132 includes suction pipeline 28, supply pipeline 76, return pipeline 78, and distribution header 80 coupled to housing 20 and in flow communication with supply pipeline 76 and return pipeline 78 as previously described. Moreover, fluid system132 includes a heat exchanger 134, a regulator 136, a flow control device 138, a heat exchange return pipeline 140, and a filter 142.
Supply pipeline 76, return pipeline 78, and distribution header 80 are coupled to housing 20 and in flow communication with interior 40 of housing 20. More particularly, supply pipeline 76 is coupled in flow communication with inlet suction pipeline 28 and motor end cover 38. Flow control device 82 is coupled to inlet suction pipeline 28 between supply pipeline 76 and motor end cover 38. During normal operation, flow control device 28 is open. Filter 142 is coupled in flow communication to supply pipeline 76. Filter 142 is configured to mitigate and/or prevent introduction of contaminants present in fluid 30 into housing 20. Supply pipeline 76 is coupled in flow communication with compressor portion 24 via inlet 144.
Return pipeline 78 is coupled in flow communication to housing 20 and supply pipeline 76. Pipelines 76 and 78 may be fabricated of metal, rubber, polyvinylchloride (PVC), or any material that attains predetermined operational parameters associated with the fluid being transported and the location of assembly 14. Pipelines 76 and 78 are sized to facilitate initial filling, and subsequently facilitate maintaining fluid pressure within housing 20 at a pre-determined operating pressure. Return pipeline 78 includes motor return pipeline 86 and compressor return pipeline 88. Motor return pipeline 86 is coupled in flow communication to motor portion 22 and to supply pipeline 76. Motor return pipeline 86 includes flow control device 90 located between housing 20 and supply pipeline 76. Compressor return pipeline 88 is coupled in flow communication to compressor portion 24 and to heat exchanger 134. Compressor return pipeline 88 includes flow control device 92 located between housing 20 and heart exchanger 134.
Distribution header 80 includes first outlet 94, second outlet 96 and third outlet 97 and distribution channel 98 located between first and second outlets 94 and 96. In the exemplary embodiment, first outlet 94 of distribution header 80 includes motor inlet 114 and third outlet 97 includes compressor inlet 116. Distribution header 80 further includes a flow control device 118 between motor inlet 114 and distribution channel 98, and includes flow control device 120 between compressor inlet 116 and distribution channel 98. Moreover, temperature control system 10 includes a flow direction device 101 that is coupled to housing 20 and in flow communication with compressor inlet 116. Flow direction device 101 is configured to channel fluid 30 from compressor inlet 116 and across at least one of bearing 66 and coupler 60. Flow direction device 101 is configured to facilitate directing fluid 30 from header 80 and toward bearing 66 and coupler 60 because compressor inlet 166 is positioned adjacent to high pressure area of compressor 16. In the exemplary embodiment, flow control device 101 includes a seal such as, but not limited to, a labyrinth seal which may includes a non-contacting seal and/or a contact seal. Any structure for enabling fluid flow may be used that enables temperature control system 10 and electrical machine 12 to function as described herein.
Heat exchanger 134 is coupled to housing 20 and in flow communication with motor portion 22. In the exemplary embodiment, heat exchanger 134 is coupled to and in flow communication with compressor return pipeline 88. Moreover, heat exchanger 134 is coupled and in flow communication with return pipeline 140. Regulator 136 is coupled to and in flow communication with heat exchanger 134. Regulator 136 is controlled by controller 104 based on pre-determined operating characteristics such as, but not limited to, motor temperature and compressor temperatures. Heat exchanger return pipeline 140 is coupled to supply pipeline 76 and in flow communication with motor portion 22 via motor end cover 38. Return pipeline 140 includes flow control device 138 such as, but not limited to, a check valve that is configured to facilitate maintaining a predetermined rate of fluid flow and a predetermined rate of pressurization of housing 20. During normal operation of system 10, flow control device 138 is normally closed to facilitate fluid flow from heater exchanger 134 to other systems (not shown).
In the exemplary embodiment, heat exchanger 134 is located at predetermined distances from housing 20 to facilitate conductive heat transfer from heat exchanger 134 to an environment 148 external to housing 20. Alternatively, configurations (not shown) for heat exchanger 134 may include, but not be limited to, heat exchanger 134 positioned in contact with housing 20 and/or heat exchanger 134 being configured to be integral with portions of housing 20 and/or internal to housing 20. Heat exchanger 134 may be positioned in environments 148 wherein external temperatures on housing 20, or the temperature of the fluid 30 within housing 20, are such that effective conductive heat transfer using the methods and apparatus of the exemplary embodiments as discussed above may not be fully facilitated.
During operation, fluid 30 is channeled from suction pipeline 28 and into supply pipeline 76. During normal operation, flow control device 82 is normally open to facilitate channeling fluid 30 from supply pipeline 76 through passageway 84 and in flow communication with fluid mover 72. Fluid 30 is channeled into and through motor portion, compressor portion and distribution header 80 as previously described. A portion of fluid 30 is channeled through motor inlet 114 and into motor portion 22 and through compressor inlet 116 and inlet compressor portion 24. Moreover, a portion of fluid 30 is channeled through second outlet 96 and into compressor portion 24. In the exemplary embodiment, fluid 30 is channeled through housing 20 via supply pipeline 76 and heat is removed from motor portion 22 and/or compressor portion 24 as in the exemplary embodiments and then fluid 30 is channeled through heat exchanger 134, wherein heat is transferred from fluid 30 and to environment 148 external to housing 20.
During other operations such as start up of electrical machine 12 and/or adding another electrical machine (not shown) to work in combination with electrical machine 12, increased temperature of fluid 30 may be required for electrical machine 12. During operations for increased fluid temperature, controller 104 is configured to close normally open flow control device 82 and to open normally closed flow control device 138. Fluid 30 is channeled from heat exchanger 134, through heat exchange return pipeline 140 and to supply pipeline 76 and subsequently to fluid mover 72 for flow through housing 20.
Fig. 4 is a cross-sectional schematic view of an alternative fluid temperature control system 150 used with an electrical machine 152. Moreover, in Fig. 4, the same reference numerals are used to indicate identical components previously described. Fluid system 150 further includes supply pipeline 76, return pipelines 78, distribution header 80, and compressor outlet pipeline 36 as previously described. In the exemplary embodiment, electrical machine 152 includes a plurality of compressors 16 such as, but not limited to, a first compressor 154 and a second compressor 156 located on opposite sides of motor 18. First and second compressors 154 and 156 are in fluid communication with motor 18 within housing 20. Couplers 60 are configured to couple first and second compressors 154 and 156 to motor shaft 48. Electrical machine 152 with two compressors 154 and 156 driven by single motor 18 facilitates reducing axial thrust and increasing flow rates as compared to known compressors (not shown). Fluid system 150 includes fluid mover 72 such as, but not limited to a fan, that is coupled to motor shaft 48. Fluid mover 72 is configured to channel fluid 30 across electrical machine 152 and across first and second compressors 154 and 156 and associated bearings (not shown) and couplers 60.
Fig. 5 is a cross-sectional schematic view of an alternative fluid temperature control system 158 used with an electrical machine 160. Moreover, in Fig. 5, the same reference numerals are used to indicate identical components previously described in Fig. 4. For electrical machine 154, couplers 60 are exposed to ambient environment 148 to facilitate heat transfer from couplers 60.
Fig. 6 is a flowchart illustrating an exemplary method 200 of applying thermal controls for operating a compressor driven by an electric motor, for example machine 12 (shown in Fig. 1). Method 200 includes moving 210 a fluid, such as fluid 30 (shown in Fig. 1), from a low pressure side of machine, such as inlet suction pipeline 28 and into a housing, for example housing 20 (shown in Fig. 1). The housing includes a motor portion, such as motor portion 22 (shown in Fig. 1), disposed about the motor, for example motor 18 (shown in Fig. 1) and a compressor portion, such as compressor portion 24 (shown in Fig. 1), and disposed about the compressor, for example compressor 16 (shown in Fig. 1). Fluid, for example fluid 30 (shown in Fig. 1), is moved 220 within motor portion and across the motor and moved within the compressor portion via compression by fluid mover mechanically coupled to motor or/and compressor shaft, such as cooling fan 72 (shown in Fig.1). Method 200 includes directing 230 fluid across temperature sensitive elements in motor and compressor, such as but not limited to bearings 54, 56, 66 and 68 and shaft coupler 60 (as shown in Fig.1) within a distribution header, such as distribution header 80 (shown in Fig. 1), which is in flow communication with locations of the temperature sensitive elements. Method 200 further includes channeling fluid across motor temperature sensitive components such as, but not limited to stator windings, electrical connection plugs and rings, air gaps between rotor and stator. Fluid is then discharged from housing and into suction port of the compressor. The discharged fluid is mixed with fluid in suction pipeline 28, upstream of the compressor. In the exemplary embodiment, fluid 30 is discharged through a heat exchanger such as heat exchanger 134 (shown in Fig. 3).
The embodiments described herein provide an integral temperature control system for thermal treatment of an electrical machine. The electrical machine can include a turbo-generator which can include a turbine section and electric machine section, a housing a turbine rotor that is rotatably coupled to an electric machine rotor. The fluid mover can be rotatably coupled to the turbine and/or an electrical machine rotor. The temperature control system thermally treats, such as cooling and/or heating, a motor portion and a compressor portion of the machine, wherein the motor portion and compressor portion are in fluid communication. The temperature control systems can include a single source of pressurized fluid and a single supply assembly to thermally treat various components and/or sub-systems with the motor portion and the compressor portion. The system channels fluid from a low pressure side of the machine and upstream from the compressor to facilitate heat transfer of the motor portion and compressor portion using a single, integrated temperature control assembly. The temperature control systems include flow controls for optimizing fluid supply to various points in the motor portion and the compressor portion. Flow control devices may be, but not be limited to, a valves and flow orifices. Any type of valve or orifice may be used that enables electrical machine to function as described herein. The temperature control systems described herein provide efficiency, reliability, and reduced maintenance costs and outages.
Parameters associated with the materials used to fabricate components of the electrical machine and temperature control system include, but are not limited to, having sufficient heat transfer properties to facilitate conductive heat transfer, and having sufficient strength and corrosion resistance to mitigate distortion and corrosion during operation. Properties associated with the materials used to fabricate assembly and fluid system include, but are not limited to having sufficient strength and corrosion resistance to mitigate wall distortion and corrosion during operation as well as sufficient flexibility to facilitate pressure equalization as described above during dynamic conditions may also include properties that facilitate conductive heat transfer. Assembly and fluid system may be fabricated from materials that include, but are not limited to metals, plastics and ceramic composites.
The embodiments described herein provide a shaft-powered, fluid mover such as a fan that facilitates enhanced cooling and heat dissipation by using the motor shaft as a fluid mover. The shaft mounted fan is configured to facilitate heat transfer of the motor, the compressor, the bearings and the coupler between the motor and the compressor together by branching a portion of the suction fluid flow and returning the fluid to the compressor suction line. Moreover, by using a fan with predefined operating characteristics, the fan can be selected based at least on motor resistance so as to operate the fan at its best efficiency performance and with minimum noise. With better cooling and heat dissipation more power can be supplied by the motor and with better efficiency. Thus, motor output power can be increased with less electrical and mechanical frictional losses. Fan performance depends on its own operating characteristics. Therefore, the fan is designed for best performance in terms of efficiency, flow rate and noise.
Exemplary embodiments of systems and methods for using a temperature control system are described above in detail. The systems and methods are not limited to the specific embodiments described herein, but rather, components of systems and/or steps of the method may be utilized independently and separately from other components and/or steps described herein. Each component and each method step may also be used in combination with other components and/or method steps. Although specific features of various embodiments may be shown in some drawings and not in others, this is for convenience only. Any feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
Various aspects and embodiments of the present invention are defined by the following numbered clauses:

1. An electrical machine comprising:
- a motor comprising a stator and a rotor, said rotor comprising a rotor shaft;
- a compressor rotatably coupled to said motor and comprising a compressor shaft;
- a housing enclosing said motor and said compressor, said housing comprising a suction pipeline in flow communication with said compressor, said suction pipeline configured to channel a fluid into said housing; and
- a temperature control assembly coupled in flow communication to said housing, said temperature control assembly comprising:
  - a fluid mover coupled to at least one of said rotor shaft and said compressor shaft and in flow communication with said suction pipeline upstream from said compressor to channel the fluid from said suction pipeline and across at least one of said motor and said compressor; and
  - a distribution header coupled to said housing and in flow communication with said fluid mover, said distribution header comprising a first outlet coupled in flow communication to said motor to channel the fluid across said motor.
2. The electrical machine of clause 1, wherein said housing comprises a return pipeline coupled in flow communication to said suction pipeline.
3. The electrical machine of any preceding clause, further comprising a motor opposite drive end bearing and a motor drive end bearing coupled to said rotor shaft, said fluid mover is configured to channel the fluid across at least one of said motor bearings, said rotor, and said stator.
4. The electrical machine of any preceding clause, further comprising a shaft coupler coupled to said rotor shaft and said compressor shaft in flow communication with said distribution header.
5. The electrical machine of any preceding clause, comprising a compressor opposite drive end bearing coupled to said compressor shaft wherein said first outlet is configured to channel fluid across at least one of said compressor bearing, said shaft coupler, and said compressor.
6. The electrical machine of any preceding clause, further comprising a motor bearing coupled to said rotor shaft in flow communication with said first outlet and a compressor opposite drive end bearing coupled to said compressor shaft in flow communication with said first outlet.
7. The electrical machine of any preceding clause, further comprising a second outlet coupled in flow communication to said compressor to channel the fluid across said compressor.
8. The electrical machine of any preceding clause, wherein said temperature control assembly comprises a discharge pipeline and a heat exchanger coupled to said discharge pipeline and between said housing and said fluid mover.
9. The electrical machine of any preceding clause, wherein said heat exchanger is in flow communication with said fluid mover.
10. The electrical machine of any preceding clause, further comprising a normally open valve coupled to said suction pipeline and to said housing in flow communication with said fluid mover and a normally closed valve coupled to said heat exchanger and said housing in flow communication with said fluid mover.
11. A temperature control system for use in cooling an electrical machine, said system comprising:
- a housing having a motor portion, a compressor portion and a suction pipeline, said motor portion, said compressor portion and said suction pipeline configured in flow communication;
- a temperature control assembly coupled to said housing and comprising a distribution header coupled in flow communication to said motor portion and said compressor portion; and
- a fluid mover coupled to said motor portion and in flow communication with said suction pipeline upstream from said compressor portion, said fluid mover configured to channel a fluid from said suction pipeline and within said motor portion, said compressor portion and said distribution header.
12. The temperature control system of any preceding clause, wherein said distribution header is coupled to said housing in flow communication with a shaft coupler of the electrical machine.
13. The temperature control system of any preceding clause, wherein said distribution header comprises a first outlet coupled in flow communication to said motor portion and a second outlet coupled to said housing in flow communication to said compressor portion.
14. The temperature control system of any preceding clause, wherein said temperature control assembly comprises a motor return pipe and a compressor return pipe coupled in flow communication to said suction pipeline upstream from said compressor portion.
15. The temperature control system of any preceding clause, wherein said distribution header couples to said housing in flow communication with a motor bearing and a compressor bearing of the electrical machine.
16. The temperature control system of any preceding clause, wherein said compressor portion includes a first compressor portion and a second compressor portion which are coupled in flow communication with said distribution header.
17. The temperature control system of any preceding clause, further comprising a heat exchanger coupled in flow communication to said housing and to said fluid mover.
18. A temperature control system for use in cooling an electrical machine, said system comprising:
- a housing having a motor portion, a compressor portion and a suction pipeline, said motor portion, said compressor portion and said suction pipeline configured in flow communication;
- a temperature control assembly coupled to said housing and comprising a distribution header coupled in flow communication to said motor portion and said compressor portion;
- a fluid mover coupled to said motor portion and in flow communication with said suction pipeline upstream from said compressor portion, said fluid mover configured to channel a fluid from said suction pipeline and within said motor portion, said compressor portion and said distribution header; and
- a heat exchanger coupled in flow communication to said housing and to said fluid mover.
19. The temperature control system of any preceding clause, wherein said heat exchanger is in flow communication with said fluid mover.
20. The temperature control system of any preceding clause, further comprising a normally open valve coupled to said suction pipeline and to said housing in flow communication with said fluid mover and a normally closed valve coupled to said heat exchanger and said housing in flow communication with said fluid mover.

Claims

An electrical machine including:
a motor (18) including a stator (44) and a rotor (42), said rotor including a rotor shaft (48);

a compressor (16) rotatably coupled to said motor and including a compressor shaft (58);

a housing (20) enclosing said motor and said compressor, said housing including a suction pipeline (28) in flow communication with said compressor, said suction pipeline configured to channel a fluid (30) into said housing; and

a temperature control assembly coupled in flow communication to said housing, said temperature control assembly including:
a fluid mover (72) coupled to at least one of said rotor shaft and said compressor shaft and in flow communication with said suction pipeline upstream from said compressor to channel the fluid from said suction pipeline and across at least one of said motor and said compressor; and

a distribution header coupled to said housing and in flow communication with said fluid mover, said distribution header including a first outlet (94) coupled in flow communication to said motor to channel the fluid across said motor.
The electrical machine of Claim 1, wherein said housing (20) comprises a return pipeline (78) coupled in flow communication to said suction pipeline (28).
The electrical machine of Claim 1 or Claim 2, further including a motor (18) opposite drive end bearing (56) and a motor drive end bearing coupled to said rotor shaft (48), said fluid mover (72) is configured to channel the fluid (30) across at least one of said motor bearings (52), said rotor (42), and said stator (44).
The electrical machine of Claim 1, 2 or 3, further including a shaft coupler (60) coupled to said rotor shaft (48) and said compressor shaft in flow communication with said distribution header.
The electrical machine of Claim 4, including a compressor (16) opposite drive end bearing (56) coupled to said compressor shaft (58) wherein said first outlet (94) is configured to channel fluid (30) across at least one of said compressor bearing, said shaft coupler (60), and said compressor.
The electrical machine of any one of Claims 1 to 5, further including a motor bearing (52) coupled to said rotor shaft (48) in flow communication with said first outlet (94) and a compressor (16) opposite drive end bearing (56) coupled to said compressor shaft (58) in flow communication with said first outlet (94).
The electrical machine of any one of Claims 1 to 6, further including a second outlet (96) coupled in flow communication to said compressor (16) to channel the fluid (30) across said compressor.
The electrical machine of any one of Claims 1 to 7, wherein said temperature control assembly comprises a discharge pipeline (34) and a heat exchanger (134) coupled to said discharge pipeline and between said housing (20) and said fluid mover (72).
The electrical machine of Claim 8, wherein said heat exchanger (134) is in flow communication with said fluid mover (72).
The electrical machine of Claim 8 or Claim 9, further including a normally open valve coupled to said suction pipeline (28) and to said housing (20) in flow communication with said fluid mover (72) and a normally closed valve coupled to said heat exchanger (134) and said housing in flow communication with said fluid mover.
A temperature control system for use in cooling an electrical machine, said system comprising:
a housing (20) having a motor portion (18), a compressor portion (16) and a suction pipeline (28), said motor portion, said compressor portion and said suction pipeline configured in flow communication;

a temperature control assembly coupled to said housing (20) and comprising a distribution header coupled in flow communication to said motor portion and said compressor portion; and

a fluid mover (72) coupled to said motor portion and in flow communication with said suction pipeline upstream from said compressor portion, said fluid mover configured to channel a fluid from said suction pipeline and within said motor portion, said compressor portion and said distribution header.
A temperature control system for use in cooling an electrical machine, said system comprising:
a housing (20) having a motor portion (18), a compressor portion (16) and a suction pipeline (28), said motor portion, said compressor portion and said suction pipeline configured in flow communication;

a temperature control assembly coupled to said housing (20) and comprising a distribution header coupled in flow communication to said motor portion and said compressor portion;

a fluid mover (72) coupled to said motor portion and in flow communication with said suction pipeline upstream from said compressor portion, said fluid mover configured to channel a fluid from said suction pipeline and within said motor portion, said compressor portion and said distribution header; and

a heat exchanger coupled in flow communication to said housing and to said fluid mover.
The temperature control system of Claim 12, wherein said heat exchanger is in flow communication with said fluid mover (72).
The temperature control system of Claim 12 or Claim 13, further comprising a normally open valve coupled to said suction pipeline and to said housing in flow communication with said fluid mover and a normally closed valve coupled to said heat exchanger and said housing in flow communication with said fluid mover.