COOLING OF STATOR AND WINDINGS OF AN ELECTRIC MOTOR IN AN INTEGRATED COMPRESSOR

Abstract

An integrated compressor includes an electric motor (130) that is susceptible to high temperatures. In a first cooling device, axial and / or radial cooling channels (250, 260, 270) are provided through the stator (132) of the motor (130) to supply coolant to parts of the stator (132) that are susceptible to high temperatures. In a second cooling device, the coolant is sprayed onto the end windings (230) of the motor (130) via nozzles (290, 430, 612) to cool the end windings (230).

Description

Technical area

[0001] The embodiments described herein relate generally to integrated compressors and, more particularly, to cooling the stator and / or windings of an electric motor in an integrated compressor. background

[0002] Integrated compressors are hermetically sealed systems in which a compressor is coupled to an electric motor. During operation of an integrated compressor, the electric motor is exposed to high pressures and / or dense cooling gases. Keeping the temperatures of the motor, including the windings and rotor, below their critical temperatures is important for the health, service life, efficiency, and operating range of the electric motor. The temperatures of these critical components are determined by the geometry of the electric motor, the properties of the solid material, electromagnetic losses, winding losses, the temperature of the cooling gas, and the like.

[0003] US patent No. 8,597,001 describes a turbocompressor in which the stator is cooled by cooling gas passages, including a radial gas passage through the stator. Furthermore, the end windings are cooled by radial holes, all of which have the same radial distance from the longitudinal axis of the turbocompressor.

[0004] Patent No. US 10,243,419 describes an electric motor with stator windings cooled by a winding groove around the insulation of the stator windings. To cool the stator windings, cooling fluid is supplied to the winding grooves.

[0005] The present disclosure aims to overcome one or more of the problems discovered by the inventors. Brief description

[0006] In one embodiment, a motor comprises: a motor rotor having a longitudinal axis; a motor stator surrounding the motor rotor and concentric with the longitudinal axis, the motor stator having at least one axial cooling channel extending through the motor stator parallel to the longitudinal axis; and an air gap between the motor stator and the motor rotor.

[0007] In one embodiment, a motor comprises: a motor rotor having a longitudinal axis; a motor stator surrounding the motor rotor and concentric with the longitudinal axis; and an air gap between the motor stator and the motor rotor, wherein the motor stator has at least one cooling channel extending through the motor stator parallel to the longitudinal axis and a plurality of radial cooling channels extending through the motor stator perpendicular to the longitudinal axis, wherein for each of the plurality of radial cooling channels, a first end of the radial cooling channel is in fluid communication with the air gap and a second end of the radial cooling channel is in fluid communication with at least one cavity extending radially outward from the motor stator, and wherein at least a subset of the plurality of radial cooling channels is in direct fluid communication with the at least one axial cooling channel.

[0008] In one embodiment, an integrated compressor comprises: a shaft having a longitudinal axis; a plurality of rotor assemblies attached to the shaft; and a motor rotating the shaft about the longitudinal axis, the motor comprising a motor rotor concentric with the longitudinal axis, a motor stator surrounding the motor rotor and concentric with the longitudinal axis, the motor stator comprising at least one axial cooling channel extending through the motor stator parallel to the longitudinal axis, and an air gap between the motor stator and the motor rotor. Brief description of the drawings

[0009] The details of the embodiments of the present disclosure, both as to their structure and their operation, may be taken in part from the accompanying drawings, in which like reference numerals refer to like parts and in which: Fig. 1 is a schematic cross-sectional view of an integrated compressor according to an embodiment; Fig. 2 is a schematic cross-sectional view of a portion of the motor of an integrated compressor according to one embodiment; Fig. 3 is a perspective view of a portion of the motor of an integrated compressor as used in one embodiment; Fig. 4 is a schematic cross-sectional view of a portion of a motor of an integrated compressor according to an embodiment; Fig. 5 is a perspective view of a portion of a motor of an integrated compressor according to an embodiment; Fig. 6 is a schematic cross-sectional view of a portion of a motor of an integrated compressor according to one embodiment; and Fig. 7 is a perspective view of a portion of a motor of an integrated compressor according to one embodiment. Detailed description

[0010] The following detailed description, taken in conjunction with the accompanying drawings, is intended to describe various embodiments and is not intended to represent the only embodiments in which the disclosure may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of the embodiments. However, it will be apparent to those skilled in the art that embodiments of the invention may be practiced without these specific details. In some instances, well-known structures and components are shown in simplified form to facilitate description.

[0011] For clarity and ease of explanation, some surfaces and details may be omitted from this description and the figures. Furthermore, the terms "front" and "rear" are used to describe the relative positions of the components shown in the drawings and do not imply an absolute orientation of the components or their relationship to a fluid flow, e.g., gas. The terms "side," "top," "bottom," "front," "back," "above," "below," and similar terms are used herein only for convenience to describe the relative positions of the various components and do not imply a particular absolute orientation of these components (e.g., relative to the external environment or the ground).

[0012] Furthermore, the components depicted here are not necessarily drawn to scale. In other words, the features depicted in the various embodiments may be implemented with different relative dimensions within and between the components than those shown in the drawings.

[0013] Fig. 1 is a schematic cross-sectional view of an integrated compressor 100 as used in one embodiment. The integrated compressor 100 includes a compressor housing enclosing a shaft 110 having a central longitudinal axis L. The shaft 110 may be comprised of a plurality of interconnected components. A number of other components of the integrated compressor 100 are concentric with the longitudinal axis L and may be arranged annularly around the longitudinal axis L. A radial axis may refer to any axis or direction radiating outward from the longitudinal axis L at a substantially orthogonal angle to the longitudinal axis L, such as the radial axis R in Fig. 1. The term "radially outward" therefore means further away from the longitudinal axis L, while the term "radially inward" means closer to the longitudinal axis L. In the following, the term "radial" refers to any axis or direction substantially perpendicular to the longitudinal axis L, and the term "axial" refers to any axis or direction substantially parallel to the longitudinal axis L.

[0014] In one embodiment, the integrated compressor 100 includes a first bearing system 120A, a motor 130, a compression system 140, a second bearing system 120B, and a thrust bearing system 150. The first bearing system 120A and the second bearing system 120B (collectively referred to herein as bearing systems 120) may include a radial magnetic bearing (RMB) arranged annularly about the longitudinal axis L. Each bearing system 120 may, for example, include an RMB stator 122 arranged concentrically with an RMB rotor 124 about the longitudinal axis L. The RMB rotor 124 may form a component of the shaft 110 or be fixed thereto. The RMB stator 122 utilizes a magnetic suspension force to suspend the RMB rotor 124 at the center of the RMB stator 122 without contacting the RMB stator 122. Thus, the shaft 110 including the RMB rotor 124 can rotate freely in the RMB stator 122 without physically touching the RMB stator 122.Similarly, the thrust bearing system 150 may include a magnetic thrust bearing (TMB) arranged annularly around the longitudinal axis L. The magnetic thrust bearing may also include a stator and a rotor arranged concentrically with the stator and suspended within the stator by a magnetic force, but designed to accommodate axial thrust forces during operation of the integrated compressor 100.

[0015] The motor 130 consists of a motor stator 132 and a motor rotor 134. The motor stator 132 may contain one or more electromagnetic coils in the form of windings that can be connected to a power source. When energy flows through the electromagnetic coil(s), a magnetic field is generated that drives the motor rotor 134 about the longitudinal axis L. The motor rotor 134 may form a component of the shaft 110 or be attached to it, so that the motor rotor 134, and thus the shaft 110, rotates within the housing of the integrated compressor 100 when the motor stator 132 is supplied with power.

[0016] The compression system 140 may include one or more stages of rotor assemblies. The working fluid (e.g., the primary gas such as air, methane, etc.) is fed into the first stage of the compression system 140 via an inlet path 142. The inlet path 142 may include a radial channel through the housing of the integrated compressor 100 to provide fluid communication between the exterior of the integrated compressor 100 and the first stage of the compression system 140. The inlet path 142 may be connected to a pipeline (e.g., via the attachment of appropriate flanges) or another source of the working fluid. The working fluid is compressed in each stage of the compression system 140. Each stage of the compression system 140 may consist of one or more blades attached to the shaft 110, extending radially therefrom, and rotating with the shaft 110.After the working fluid has been compressed in the final stage of the compression system 140, the working fluid may be discharged via an outlet path 148. The outlet path 148 may be a radial channel through the housing of the integrated compressor 100. The outlet path 148 may be connected to a pipeline (e.g., via the attachment of appropriate flanges) or another destination for the compressed working fluid.

[0017] A bleed path 144 may fluidly connect the compression system 140 to the coolant system of the engine 130 to direct the working fluid from the compression system 140 to the coolant inlet of the engine 130. In other words, relatively cool working fluid is removed from one or more stages of the compression system 140 and supplied as coolant to the engine 130 via the bleed path 144. Similarly, a re-intake path 146 may fluidly connect the coolant system of the engine 130 to the inlet path 142 to reintroduce the working fluid from the coolant outlet of the engine 130 into the compression system 140. In other words, the coolant that has removed heat from the engine 130 is withdrawn from the engine 130 and supplied as working fluid to the first stage of the compression system 140.

[0018] It should be understood that the integrated compressor 100 shown is only one example of an integrated compressor. Although the integrated compressor 100 is shown as a beam compressor, the integrated compressor 100 may also be constructed differently, such as a centrifugal compressor (e.g., with the inlet and outlet of the compression system 140 on opposite sides of the motor 130). The arrangement of the bearing systems 120 and 150 may vary depending on the chosen design. Furthermore, various types of motors 130 may be used in the integrated compressor 100, such as motors with any number of poles.

[0019] Fig. Figure 2 is a schematic cross-sectional view of a portion of the motor 130 of the integrated compressor 100, as used in one embodiment. An air gap 210 is located between the motor stator 132 and the motor rotor 134. Also located on either side of the motor stator 132 are end winding cavities 220A and 220B, which house the end windings 230A and 230B, respectively. Each end winding 230 extends from one end of the motor stator 132 and conducts current to generate the magnetic field that drives the motor rotor 134. Inlets 242A and 242B may extend radially outward from the motor stator 132 and may be supplied with coolant to cool the motor stator 132 (e.g., via the bleed path 144). The cavities 244A and 244B may be located radially outward of the motor stator 132 and form a flow path between the radial cooling channels described herein.In one embodiment, cavities 244A and 244B may also be inlets supplied with coolant for cooling motor stator 132. In this case, inlets 242A and 242B may be primary inlets with higher coolant flow rates, and cavities 244A and 244B may be secondary inlets with lower coolant flow rates. Outlet 246 may extend radially outward from motor stator 132 and provide an exit for the coolant flowing through motor stator 132 (e.g., via reintroduction path 146). As previously mentioned, the coolant may be a compressed working fluid taken from one of the stages of compression system 140 and directed into inlets 242A and / or 242B via exhaust path 144.

[0020] It should be understood that the letter may be omitted from a reference number here if a reference to an element can be applied equally to all components that share the numerical portion of that reference number. For example, a reference to end winding cavity 220 may apply to front end winding cavity 220A and / or rear end winding cavity 220B. Similarly, a reference to end winding 230 may also refer to end windings 230A and 230B, a reference to inlet 242 may also refer to inlets 242A and 242B, a reference to cavity 244 may also refer to cavities 244A and 244B, etc.

[0021] As shown, a plurality of cooling channels may be formed in the motor stator 132. For example, an axial cooling channel 250 may extend axially through the motor stator 132. The axial cooling channel 250 may be in fluid communication with the end winding cavity 220A at the front end and with the end winding cavity 220B at the rear end. The axial cooling channel 250 may be positioned closer to the air gap 210 than to the inlets 242, the cavities 244, and the outlet 246 to enhance cooling of the motor stator 132 in the region where it is subject to higher temperatures (i.e., closer to the air gap 210). It should be understood that the motor stator 132 may include a plurality of axial cooling channels 250 that are parallel to one another and at the same radial distance from the longitudinal axis L and are evenly spaced around the longitudinal axis L (e.g., equally spaced).Although not shown, different sets of axial cooling channels 250 may be arranged at different radial distances from the longitudinal axis L to stagger the axial cooling within the motor stator 132. In this case, the density of the axial cooling channels 250 may be greater at a radially inner end of the motor stator 132 than at a radially outer end of the motor stator 132 to achieve greater cooling in the radially inner portion of the motor stator 132.

[0022] In addition to the axial cooling channels 250, radial cooling channels 260 and 270 may also extend radially through the motor stator 132. In one embodiment, the radial cooling channels 260 are not in direct flow communication with the axial cooling channel 250, while the radial cooling channels 270 are in direct flow communication with the axial cooling channel 250. In the cross-section shown, three radial cooling channels 260A, 260B, and 260C are located upstream of three radial cooling channels 270A, 270B, and 270C, and three radial cooling channels 260D, 260E, and 260F are located downstream of the radial cooling channels 270A, 270B, and 270C. However, it is understood that other configurations are possible, e.g., B. a different number (e.g., zero, one, two, four, five, etc.) of front radial cooling channels 260, a different number (e.g., zero, one, two, four, five, etc.) of rear radial cooling channels 260, and / or a different number (e.g., zero, one, two, four, five, etc.) of radial cooling channels 270.Additionally, the motor stator 132 may include a plurality of radial cooling channels 260A, 260B, 260C, 270A, 270B, 270C, 260D, 260E, 260F evenly spaced about the longitudinal axis L.

[0023] In one embodiment, the density of the radial cooling channels 260 and 270 may increase from a front axial end of the motor stator 132 toward the center of the motor stator 132 and / or increase from a rear axial end of the motor stator 132 toward the center of the motor stator 132. In other words, the density of the radial cooling channels 260 and 270 may be greater in the axial center of the motor stator 132 because higher temperatures exist there than at the axial ends. Furthermore, the density of the radial cooling channels 260 and 270 may be greater in the rear half of the motor stator 132 than in the front half of the motor stator 132 because higher temperatures may occur in the rear half of the motor stator 132 than in the front half of the motor stator 132.

[0024] For example, in the illustrated embodiment, the front half of the motor stator 132 includes three radial cooling channels 260A, 260B, and 260C that are not in fluid communication with the axial cooling channel 250, wherein the distance between the front edge of the motor stator 132 and the radial cooling channel 260A is greater than the distance between the radial cooling channels 260A and 260B, the distance between the radial cooling channels 260A and 260B is greater than the distance between the radial cooling channels 260B and 260C, and the distance between the radial cooling channels 260B and 260C is greater than the distance between the radial cooling channels 260C and 270A. The radial cooling channels 270A, 270B and 270C, which are in direct flow communication with the axial cooling channel 250, are arranged substantially in the center of the motor stator 132 (e.g., symmetrically).The rear half of the motor stator 132 includes three radial cooling channels 260D, 260E, and 260F that are not in direct flow communication with the axial cooling channel 250. The distance between the radial cooling channels 260D and 260E is greater than the distance between the radial cooling channels 270C and 260D, the distance between the radial cooling channels 260E and 260F is greater than the distance between the radial cooling channels 260D and 260E, and the distance between the radial cooling channel 260F and the rear edge of the motor stator 132 is greater than the distance between the radial cooling channels 260E and 260F. It should be understood that this is only a non-limiting example and that other configurations of the cooling channels 260 and / or 270 are possible depending on the particular characteristics of the stator 132.In general, the density of the cooling channels 260 and 270 should be greater in the areas of the stator motor 132 where higher temperatures occur than in the areas of the stator motor 132 where lower temperatures occur.

[0025] Cooling channels 250, 260, and 270 allow coolant, which may be the same as the working fluid, to flow through the motor stator 132, thereby cooling it. Specifically, each axial cooling channel 250 allows coolant to flow axially through the motor stator 132. Each radial cooling channel 260 allows coolant to flow radially through the motor stator 132 between the air gap 210 and either the cavity 244A or 244B or the outlet 246. Similarly, each radial cooling channel 270 allows coolant to flow radially through the motor stator 132 between the air gap 210 and the outlet 246. Furthermore, each radial cooling channel 270 is in direct fluid communication with the axial cooling channel 250, allowing coolant to flow between the axial cooling channel 250 and the radial cooling channels 270.The radial cooling channels 260 and 270 are indirectly fluidly connected to each other, as they are connected to the air gap 210 and either to the cavity 244A or 244B or to the outlet 246. For example, coolant may flow from the radial cooling channel 260A into the cavity 244A and from the cavity 244A into the radial cooling channel 260B and / or vice versa. Likewise, coolant may flow from the radial cooling channel 260C into the outlet 246, and at least a portion of the coolant that does not exit through the outlet 246 may flow from the outlet 246 into the radial cooling channel 270A and / or vice versa. Likewise, coolant may flow from the radial cooling channel 270A into the outlet 246, and at least a portion of the coolant that does not exit through the outlet 246 may flow from the outlet 246 into the radial cooling channel 270B and / or vice versa.Thus, the coolant can flow between two radial cooling channels 260, between two radial cooling channels 270 and between the radial cooling channel 260 and the radial cooling channel 270.

[0026] The motor stator 132 may include a front compression plate 280A separating the end winding cavity 220A from the inlet 242A, and a rear compression plate 280B separating the end winding cavity 220B from the inlet 242B. In one embodiment, one or a plurality of nozzles 290 may be formed through the front compression plate 280A and / or the rear compression plate 280B to fluidly connect the inlet 242 to the end winding cavity 220. For example, one or a plurality of nozzles 290A may be formed through the front compression plate 280A to inject coolant from the inlet 242A into the cavity 220A to cool the end winding 230A. Likewise, one or a plurality of nozzles 290B may be formed through the rear pressure plate 280B to spray coolant from the inlet 242B into the cavity 220B to cool the end winding 230B.The nozzles 290 can be formed at any suitable angle to the radial axis, preferably in the range of 35-55 degrees, e.g., at a 45-degree angle. In particular, each nozzle 290 can be inclined toward the end coil 230 to spray the coolant from the inlet 242 toward the end coil 230.

[0027] Fig. 3 is a perspective view of a portion of the motor 130 of the integrated compressor 100, according to one embodiment. As illustrated, the inlets 242, the cavities 220 and 244, and the outlet 246 each form an annulus around the longitudinal axis L. The nozzles 290 may be arranged by the die plate 280 at equal distances around the longitudinal axis L and at one or more radial distances from the longitudinal axis L. Although the nozzles 290 are illustrated at two radial distances from the longitudinal axis L, the die plate 280 may consist of nozzles 290 at any number of radial distances from the longitudinal axis L, e.g., at a single radial distance or at three or more radial distances.

[0028] Fig. 4 is a schematic cross-sectional view of a portion of the motor 130 of the integrated compressor 100, according to one embodiment. In the illustrated embodiment, a winding shroud 400 extends radially outward from a front and / or rear end of the motor stator 132 from a position where the end winding 230 is connected to the motor stator 132, thus surrounding the end winding 230. The winding shroud 400 may be used instead of or in addition to the nozzles 290 to cool the end winding 230.

[0029] As shown in the figure, the inner diameter of the winding shell 400 may increase with increasing distance from the end of the motor stator 132. The winding shell 400 may have a shape that generally follows the shape of the end winding 230 in the axial direction, such that the radial distance between a radially inward-facing surface of the winding shell 400 and a radially outward-facing surface of the end winding 230 is substantially constant in the axial direction through the cavity 220. In other words, the inner diameter of the winding shell 400 may increase with increasing distance from the end of the motor stator 132 at the same rate as the outer diameter of the end winding 230 increases with increasing distance from the end of the motor stator 132.Alternatively, the radial distance between the radially inward-facing surface of the winding shell 400 and the radially outward-facing surface of the end winding 230 may not be constant along the axial direction through the cavity 220. It is understood that the winding shell 400 may be annular about the longitudinal axis L.

[0030] The winding shell 400 may consist of a shell portion 410 supported by ribs 420 extending radially inward from the shell portion 410 from the end of the motor stator 132. A plurality of nozzles 430 may be formed through the shell portion 410 at circumferential positions intermediate the positions of the ribs 420. The nozzles 430 may be formed as through-holes in the shell portion 410 that fluidly connect a portion of the end winding cavity 220 located radially outside the winding shell 400 with a portion of the end winding cavity 220 located radially inside the winding shell 400 and containing the end winding 230. In one embodiment, each nozzle 430 is aligned along a radial axis. Alternatively, the nozzles 430 may be arranged at an angle to the radial axis.The nozzles 430 can be arranged at a variety of positions both around the circumference of the shell portion 410 and in the axial direction. The nozzles 430 can be arranged at even intervals around the circumference of the shell portion 410 and / or in the axial direction. The coolant can be supplied to the portion of the end winding cavity 220 located radially outside the winding shell 400 to flow through the nozzles 430 and be sprayed toward the winding end 230. Since the shape of the winding shell 400 generally corresponds to the shape of the end winding 230, the coolant can be sprayed from a substantially constant distance along the entire length of the end winding 230. However, in an alternative embodiment, the shape of the winding shell 400 may not generally correspond to the shape of the end winding 230 and / or the coolant may be sprayed from different distances along the length of the end winding 230.

[0031] Fig. 5 is a perspective view of a portion of the motor 130 of the integrated compressor 100, according to one embodiment. As can be seen in the figure, the ribs 420 extend axially along the radially inward-facing surface of the shell portion 410. The spaces between adjacent ribs 420 form grooves 440 in the axial direction. Because the shape of the winding shell 400, including the shell portion 410 and the ribs 420, generally follows the shape of the end winding 230, the grooves 440 also generally follow the shape of the end winding 230, such that the radial distance between each groove 440 and the radially outward-facing surface of the end winding 230 is substantially constant in the axial direction through the cavity 220.In an alternative embodiment, the radial distance between each groove 440 and the radially outward-facing surface of the end winding 230 may not be constant along the axial direction through the cavity 220. The grooves 440 receive the fluid circulating in the portion of the cavity 220 located radially inward from the winding shell 400, which may be the same fluid as the working fluid in the integrated compressor 100. This fluid, which is typically at a higher temperature than the coolant sprayed through the nozzles 430, may circulate in the grooves 440 away from the surface and insulation of the end winding 230.

[0032] Fig. 6 is a schematic cross-sectional view of a portion of the motor 130 of the integrated compressor 100, according to one embodiment. In the illustrated embodiment, a flow splitter 600 is provided at the front and / or rear end of the motor stator 132 to reduce the volume of the end winding cavity 220. The flow splitter 600 may be used instead of or in addition to the nozzles 290 and / or the winding sleeve 400. The flow splitter 600 consists of a radial wall 610 and at least one axial wall 620 that form a radial cooling channel 630 between the end of the motor stator 132 and the radial wall 610. It should be understood that the flow splitter 600 and the radial cooling channel 630 may be arranged annularly about the longitudinal axis L.

[0033] In one embodiment, the radial cooling channel 630 is in fluid communication with the axial cooling channel 250. For example, one end of each axial cooling channel 250 may open into the radial cooling channel 630 at a radially inner end of the radial cooling channel 630. In an embodiment in which a flow splitter 600 is provided at both ends of the motor stator 132, both ends of each axial cooling channel 250 may open into the radial cooling channel 630 of the opposing flow splitters 600 at both ends of the motor stator 132 to create a fluid path between the opposing radial cooling channels 630. The coolant, which may be the same as the working fluid in the compression system 140, may be supplied to the radial cooling channel 630 from radially outside through a coolant system (e.g., by discharging the working fluid from a stage of the compression system 140 via the discharge path 144).The coolant can flow radially inward through the radial cooling channel 630 and into each axial cooling channel 250.

[0034] In one embodiment, one or more nozzles 612 may be formed through the radial wall 610 of the flow splitter 600 to fluidly connect the radial cooling channel 630 to the end winding cavity 220. The nozzles 612 may be formed at any suitable angle to the radial axis, preferably in a range of 35-55 degrees, e.g., at a 45-degree angle. In particular, the nozzles 612 may be oriented toward the end winding 230 to spray coolant from the radial cooling channel 630 toward the end winding 230. In this way, the coolant supplied to the radial cooling channel 630 is sprayed obliquely into the end winding cavity 220 through the nozzle(s) 612.

[0035] Fig.Figure 7 is a perspective view of a portion of the motor 130 of the integrated compressor 100, according to one embodiment. As shown in the figure, the flow divider 600 may be equipped with tooth-shaped devices 640 at the radially inner end of the flow divider 600. The tooth-shaped devices 640 form gaps between them to accommodate the connections of the end winding 230 to the motor stator 132. Thus, the axial cooling channel 250 can be arranged closer to the air gap 210, where temperatures in the motor stator 132 tend to be higher. Industrial applicability

[0036] An integrated compressor 100 may include a hermetically sealed electric motor 130 that drives a shaft to rotate rotor assemblies in a compression system 140. The compression system 140 compresses a fluid supplied via an inlet path 142 and discharges the compressed fluid via an outlet path 148. The integrated compressor 100 may, for example, be installed in a gas pipeline to compress gas (e.g., methane) as a working fluid. In one embodiment, a portion of this working fluid may be withdrawn from the compression system 140 and directed as coolant to one or a plurality of cooling devices in the engine 130 to cool various components of the engine 130 that are susceptible to high temperatures.

[0037] In a first cooling device, the motor stator 132 in the motor 130 of the integrated compressor 100 can be equipped with axial cooling channels 250, radial cooling channels 260 that are not in direct fluid communication with the axial cooling channel 250, and / or radial cooling channels 270 that are in direct fluid communication with the axial cooling channel 250. The density of the cooling channels can be greater in regions of the motor stator 132 where higher temperatures occur, namely in a radially inner part of the motor stator 132 compared to a radially outer part of the motor stator 132, in an axially middle part of the motor stator 132 compared to an axially outer part of the motor stator 132, and / or in a rear part of the motor stator 132 compared to a front part of the motor stator 132.In this way, a larger amount of coolant is supplied to the parts of the motor stator 132 that tend to higher temperatures than to the parts of the motor stator 132 that tend to lower temperatures.

[0038] In a second cooling device, the coolant is sprayed onto the end winding 230 using nozzles to cool it. This second device can be used in addition to or instead of the first device described above. In a first embodiment, angled nozzles 290 can be formed by a press plate 280 at the front and / or rear ends of the motor stator 132 to spray the coolant onto the end winding 230. In a second embodiment, a winding shell 400 can be formed around the front and / or rear end winding 230, generally following the shape of the end of the winding 230, with radial nozzles 430 formed by a shell portion 410 to spray the coolant into the grooves 440 between the ribs 420 onto the end of the winding 230.In a third embodiment, a flow splitter 600 may be provided at the front and / or rear ends of the motor stator 132 to form a radial cooling passage 630 in fluid communication with the axial cooling passage 250, with angled nozzles 612 formed through a radial wall 610 of the flow splitter 600 to spray coolant toward the end winding 230. One or more of these first, second, and third embodiments may be incorporated into the front and / or rear portion of the motor 130 of an integrated compressor 100 to cool the end winding 230.

[0039] It is understood that the advantages described above may apply to one or more embodiments. Aspects described in the context of one embodiment are intended to be applicable to the other embodiments as well. All explanations in the context of one embodiment apply to similar features of the other embodiments, and elements of multiple embodiments may be combined to form other embodiments. The embodiments are not limited to those that solve one or all of the stated problems or that provide one or all of the stated benefits or advantages.

[0040] The foregoing detailed description is merely exemplary in nature and is not intended to limit the invention or its application and uses. The described embodiments are not limited to use in connection with any particular type of machine. Although the present embodiments are illustrated and described in an integrated compressor for simplicity, the invention may be employed in various other types of compressors and machines with parts to be cooled, as well as in various other systems and environments. Furthermore, there is no intention to be bound by the theories presented in the preceding sections.It should also be understood that the illustrations may include exaggerated dimensions and graphic representations to better illustrate the reference objects shown and are not to be considered limiting unless expressly stated as such. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 8,597,001

[0003] US 10,243,419

[0004]

Claims

[1] Engine (130) comprising: a motor rotor (134) having a longitudinal axis (L); a motor stator (132) surrounding the motor rotor (134) and concentric with the longitudinal axis (L), wherein the motor stator (132) has at least one axial cooling channel (250) extending parallel to the longitudinal axis (L) through the motor stator (132); and an air gap (210) between the motor stator (132) and the motor rotor (134). [2] The motor (130) of claim 1, wherein the motor stator (132) further comprises one or more radial cooling channels (260) extending perpendicular to the longitudinal axis (L) through the motor stator (132) and not in direct flow communication with the at least one axial cooling channel (250). [3] The motor (130) of claim 1, wherein the motor stator (132) further comprises one or more radial cooling channels (260) extending perpendicular to the longitudinal axis (L) through the motor stator (132) and not in direct flow communication with the at least one axial cooling channel (250). [4] The motor (130) of claim 1, wherein the motor stator (132) further comprises: a first set of one or more radial cooling channels (260) extending through the motor stator (132) perpendicular to the longitudinal axis (L) and not in direct flow communication with the at least one axial cooling channel (250); and a second set of one or more radial cooling channels (270) extending through the motor stator (132) perpendicular to the longitudinal axis (L) and in direct flow communication with the at least one axial cooling channel (250), wherein the first set comprises a plurality of radial cooling channels (260), including a first radial cooling channel (260A) and a second radial cooling channel (260F), wherein the first radial cooling channel (260A) is closer to a front end of the motor stator (132) than each radial cooling channel (270) in the second set, and wherein the second radial cooling channel (260F) is closer to a rear end of the motor stator (132) than each radial cooling channel (270) in the second set, and wherein the second set comprises a plurality of radial cooling channels (270). [5] The motor (130) of claim 4, wherein the density of the second set along an axial axis parallel to the longitudinal axis (L) is greater in a rear half of the motor stator (132) than in a front half of the motor stator (132). [6] The motor (130) of claim 1, wherein the motor stator (132) includes a plurality of radial cooling channels (260, 270) extending perpendicular to the longitudinal axis (L) through the motor stator (132), and wherein for each of the plurality of radial cooling channels (260, 270), a first end of the radial cooling channel (260, 270) is in fluid communication with the air gap (210) and a second end of the radial cooling channel (260, 270) is in fluid communication with at least one cavity (244, 246) extending radially outward from the motor stator (132). [7] The motor (130) of claim 6, wherein the density of the plurality of radial cooling channels (260, 270) increases along an axial axis parallel to the longitudinal axis (L) from a front end of the motor stator (132) to the center of the motor stator (132) and increases from a rear end of the motor stator (132) to the center of the motor stator (132). [8] The motor (130) of claim 1 further comprising at least one end winding (230) connected to an end of the motor stator (132) and extending into an end winding cavity (220), the end including a press plate (280) having a plurality of nozzles (290) therethrough fluidly connecting a cavity (242) located radially outward of the motor stator (132) to the end winding cavity (220), each of the plurality of nozzles (290) being angled at an angle with respect to a radial axis (R) perpendicular to the longitudinal axis (L). [9] The motor (130) of claim 8, wherein the angle is between 35 and 55 degrees. [10] The motor (130) of claim 1, further comprising at least one end winding (230) connected to an end of the motor stator (132) and extending into an end winding cavity (220); and a winding shell (400) extending from the end of the motor stator (132) and surrounding the at least one end winding (230), wherein an inner diameter of the winding shell (400) increases with increasing distance from the end of the motor stator (132), and wherein the winding shell (400) has a shell portion (410) having a plurality of nozzles (430) extending therethrough. [11] The engine (130) of claim 10, wherein each of the plurality of nozzles (430) is oriented radially and perpendicular to the longitudinal axis (L). [12] The motor (130) of claim 11, wherein the winding shell (400) further comprises a plurality of ribs (420) extending from the end of the motor stator (132) radially inwardly of the shell portion (410) and configured to support the shell portion (410), the plurality of nozzles (430) being positioned to fluidly connect a portion of the end winding cavity (220) located radially outward of the winding shell (400) with a portion of the end winding cavity (220) located radially inward of the winding shell (400) within grooves (440) between the plurality of ribs (420). [13] The motor (130) of claim 10, wherein the inner diameter of the winding shell (400) increases with increasing distance from the end of the motor stator (132) to the same extent as an outer diameter of the at least one end winding (230) increases with increasing distance from the end of the motor stator (132). [14] The motor (130) of claim 1, further comprising at least one end winding (230) connected to an end of the motor stator (132) and extending into an end winding cavity (220); and a flow splitter (600) connected to the end of the motor stator (132), the flow splitter (600) comprising a radial wall (610) and at least one axial wall (620) defining a radial cooling channel (630) between the end of the motor stator (132) and the radial wall (610), the radial wall (610) having a plurality of nozzles (612) therethrough fluidly connecting the radial cooling channel (630) to the end winding cavity (220), and the radial cooling channel (630) being in fluid communication with the at least one axial cooling channel (250). [15] The engine (130) of claim 1, wherein the at least one axial cooling channel (250) is a plurality of axial cooling channels (250) equidistantly spaced about the longitudinal axis (L).

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