System and method for adjusting compressor position - Patents.com

Abstract

The heating, ventilation, air conditioning, and refrigeration (HVAC&R) system (10) includes a compressor (32) having a housing (100), a shaft (102) disposed within and extending through the housing (100), and an impeller (104) coupled to the shaft (102), the shaft (102) configured to rotate about an axis (120) relative to the housing (100 to rotate the impeller (104). The HVAC&R system (10) also includes a controller (134) configured to receive data indicative of a distance from a shroud (204) of the impeller (104) to the housing (100), and to adjust a position of the shaft (102) along the axis (120) based on a comparison of the distance from the shroud (204) of the impeller (104) to the housing (100) to a predetermined value.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of U.S. Provisional Application No. 63 / 342,410, entitled "SYSTEM AND METHOD FOR ADJUSTING POSITION OF A COMPRESSOR," filed on May 16, 2022, and U.S. Provisional Application No. 63 / 387,177, entitled "SYSTEM AND METHOD FOR ADJUSTING POSITION OF A COMPRESSOR," filed on December 13, 2022, each of which is incorporated by reference in its entirety for all purposes. [Background technology]

[0002] This section is intended to introduce the reader to various aspects of the art that may be related to various aspects of the present disclosure that are described below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. As such, it should be understood that these statements are to be read in this light, and not as admissions of prior art.

[0003] Chiller systems, or vapor compression systems, utilize a working fluid (e.g., refrigerant, etc.) that changes phase between a vapor, liquid, and mixtures thereof in response to exposure to different temperatures and pressures within components of the chiller system. The chiller system can place the working fluid in a heat exchange relationship with a cooling fluid (e.g., water) and deliver the cooling fluid to a conditioning device and / or an environment being conditioned by the chiller system. In such applications, the cooling fluid may pass through downstream devices, such as air handlers, to condition other fluids, such as air within a building. Chiller systems can include a compressor configured to pressurize the working fluid and circulate the working fluid through a working fluid circuit. Unfortunately, compressors can be susceptible to inefficient or undesirable operation. Summary of the Invention [Means for solving the problem]

[0004] A summary of certain embodiments disclosed herein is described below. It should be understood that these aspects are presented only to provide the reader with a brief summary of these specific embodiments, and that these aspects are not intended to limit the scope of the present disclosure. In fact, the present disclosure may encompass a variety of aspects that may not be described below.

[0005] In one embodiment, a heating, ventilation, air conditioning, and refrigeration (HVAC&R) system includes a compressor having a housing, a shaft disposed within and extending through the housing, and an impeller coupled to the shaft, the shaft configured to rotate about an axis relative to the housing to rotate the impeller. The HVAC&R system also includes a controller configured to receive data indicative of a distance from a shroud of the impeller to the housing and to adjust a position of the shaft along the axis based on a comparison of the distance from the shroud of the impeller to the housing to a predetermined value.

[0006] In another embodiment, a heating, ventilation, air conditioning, and refrigeration (HVAC&R) system includes a controller configured to receive data from a sensor disposed in the compressor indicative of a distance from a shroud of the impeller to a housing of the compressor, compare the distance to a predetermined value, and adjust a position of a shaft coupled to the impeller along an axis of rotation of the shaft and adjust a position of the impeller relative to the housing based on a comparison of the distance from the shroud of the impeller to the predetermined value.

[0007] In a further embodiment, a heating, ventilation, air conditioning, and refrigeration (HVAC&R) system includes a compressor having a housing, a shaft disposed within and extending through the housing, a thrust bearing disposed within the housing and coupled to the shaft, and an impeller disposed within the housing and coupled to the shaft, the impeller including a plurality of blades and a shroud secured to the plurality of blades. The HVAC&R system also includes a controller configured to control operation of the thrust bearing based on data indicative of a detected distance from the housing to the shroud of the impeller. [Brief description of the drawings]

[0008] The various aspects of the disclosure may be better understood by reading the following detailed description and by referring to the drawings, in which:

[0009] [Figure 1] FIG. 1 is a perspective view of a building that may utilize an embodiment of a heating, ventilation, air conditioning, and cooling (HVAC&R) system in a commercial environment, according to one aspect of the present disclosure. [Diagram 2] FIG. 1 is a perspective view of an embodiment of a vapor compression system according to one aspect of the present disclosure. [Diagram 3] FIG. 3 is a schematic diagram of an embodiment of the vapor compression system of FIG. 2 according to an aspect of the present disclosure. [Figure 4] FIG. 3 is a schematic diagram of an embodiment of the vapor compression system of FIG. 2 according to an aspect of the present disclosure. [Diagram 5] FIG. 2 is a side cross-sectional view of an embodiment of a compressor of an HVAC&R system according to one aspect of the disclosure. [Figure 6] FIG. 2 is a cross-sectional side view of an embodiment of a portion of a compressor of an HVAC&R system according to one aspect of the disclosure. [Figure 7] FIG. 2 is a cross-sectional side view of an embodiment of a portion of a compressor of an HVAC&R system according to one aspect of the disclosure. [Figure 8] FIG. 2 is a cross-sectional side view of an embodiment of a portion of a compressor of an HVAC&R system according to one aspect of the disclosure. [Figure 9]1 is a flow chart of an embodiment of a method for operating a compressor of an HVAC&R system, according to an aspect of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] One or more specific embodiments are described below. In order to provide a concise description of these embodiments, not all features of an actual implementation are described herein. It should be recognized that in the development of any such actual implementation, as with any engineering or design project, many implementation-specific decisions must be made to achieve the developer's specific goals, which may vary from implementation to implementation, such as compliance with system-related and industry-related constraints. Moreover, it should be recognized that such a development effort may be complex and time-consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill in the art having the benefit of this disclosure.

[0011] When introducing elements of various embodiments of the present disclosure, the articles "a," "an," and "the" are intended to mean that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements. In addition, it should be understood that references to "one embodiment" or "an embodiment" of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.

[0012] As used herein, terms such as "approximately," "generally," and "substantially" are intended to convey that the described attribute value may be within a relatively small range of attribute values, as would be understood by one of ordinary skill in the art. For example, when an attribute value is described as being "approximately" equal to (or, e.g., "substantially similar to") a given value, this is intended to mean that the attribute value may be within + / -5%, + / -4%, + / -3%, + / -2%, + / -1% of the given value, or even close to it. Similarly, when a given feature is described as being "substantially parallel" to another feature, "generally perpendicular" to another feature, etc., this is intended to mean that the given feature is within + / -5%, + / -4%, + / -3%, + / -2%, + / -1%, or even close to having the described property, such as being parallel to another feature, perpendicular to another feature, etc. Additionally, it should be understood that mathematical terms such as "planar," "inclined," "vertical," "parallel," and the like are intended to encompass characteristics of surfaces or elements as would be understood by one of ordinary skill in the relevant art, and should not be interpreted as strictly as would be understood in the mathematical arts. For example, a "planar" surface is intended to encompass a surface that is machined, molded, or otherwise formed, using techniques and tools available to one of ordinary skill in the art, to be substantially flat or smooth (within relevant tolerances). Similarly, a surface having an "inclined" is intended to encompass a surface that is machined, molded, or otherwise formed, using techniques and tools available to one of ordinary skill in the art, to be oriented at an angle (e.g., tilted) relative to a reference point.

[0013] Embodiments of the present disclosure relate to heating, ventilation, air conditioning, and refrigeration (HVAC&R) systems that include a vapor compression system (e.g., a vapor compression circuit) having a compressor. During operation, the compressor pressurizes a working fluid in the vapor compression system and directs the working fluid to a condenser, which may cool and condense the working fluid. The condensed working fluid may be directed to an expansion device, which may reduce the pressure of the working fluid and further cool the working fluid. From the expansion device, the cooled working fluid may be directed to an evaporator, where the working fluid is in a heat exchange relationship with a conditioned fluid and may cool the conditioned fluid.

[0014] In some embodiments, the compressor may include an impeller configured to rotate to compress the working fluid and direct the working fluid to a diffuser passage of the compressor. For example, the impeller may be coupled to a shaft, which may be configured to rotate relative to a housing of the compressor and drive the rotation of the impeller relative to the housing. However, during operation of the compressor, the shape and / or position of the impeller (e.g., relative to the housing and / or diffuser passage) may change, affecting the performance of the compressor. As an example, the position of the impeller may shift such that an outlet or flow outlet of the impeller may be offset (e.g., misaligned) relative to an opening of the diffuser passage. An offset between the flow outlet of the impeller and the opening of the diffuser passage may reduce the efficiency of the compressor. For example, a misalignment between the flow outlet of the impeller and the opening of the diffuser passage may interrupt, obstruct, or disrupt the flow of the working fluid through the compressor (e.g., from the impeller to the diffuser passage). When the flow of the working fluid through the compressor is obstructed, a pressure loss or head loss may occur, which may reduce the efficiency of the flow of the working fluid through the compressor. In additional or alternative embodiments, the position of the impeller may shift toward the housing, increasing the likelihood of contact between the impeller (e.g., impeller shroud, impeller blade tips) and the housing. Such contact may affect the structural integrity of the impeller and / or housing and / or may interrupt or disrupt operation of the compressor.

[0015] Accordingly, it is now recognized that maintaining a desired position of the impeller (e.g., within the compressor housing) during operation can improve compressor performance, reduce wear, and / or extend the useful life of the compressor. Accordingly, the present disclosure is directed to systems and methods for monitoring the position of the impeller and adjusting the position of the impeller (e.g., relative to the housing) based on the monitored position. For example, an operational parameter value indicative of the position of the impeller can be received, such as from a sensor on the compressor. In some embodiments, the operational parameter can include a distance between a surface of the impeller and the compressor housing. As one example, the impeller surface can be a surface of a shroud of the impeller. As another example, the impeller surface can be a tip of a blade of the impeller. In response to determining that the distance between the impeller surface and the compressor housing differs from a predetermined distance value and / or is outside a range of distance values ​​(e.g., a target range, a threshold range), a position of the shaft on which the impeller is mounted can be adjusted to move the impeller relative to the housing. For example, the shaft can be translated (e.g., via control of a thrust bearing coupled to the shaft) to move the impeller relative to the housing, thereby adjusting the distance between the impeller surface and the housing to be within a range of distance values.

[0016] In some cases, the predetermined distance value and / or range of distance values ​​can be associated with a desired alignment between the impeller outlet and the diffuser passage opening and / or a desired clearance between the impeller and the housing. Thus, by adjusting the position of the shaft and impeller to be approximately equal to the predetermined distance value and / or within the range of distance values, a desired alignment between the impeller outlet and the diffuser passage opening and / or a desired clearance between the impeller and the housing can be achieved. For example, maintaining the position of the shaft and impeller within the range of distance values ​​can improve efficient operation of the compressor. Indeed, the disclosed technology allows for adjustment of the position of the impeller within the compressor housing (e.g., alignment between the impeller outlet and the diffuser passage opening) during operation of the compressor, such as in response to variable operating conditions of the compressor. In this manner, operation of the compressor can be improved (e.g., more efficient) across variable operating conditions of the compressor.

[0017] Turning now to the drawings, FIG. 1 is a perspective view of one embodiment of an environment of a heating, ventilation, air conditioning, and cooling (HVAC&R) system 10 in a building 12 for a typical commercial environment. The HVAC&R system 10 may include a vapor compression system 14 (e.g., a chiller) that provides chilled liquid that may be used to cool the building 12. The HVAC&R system 10 may also include a boiler 16 to provide warm liquid for heating the building 12, and an air distribution system that circulates air through the building 12. The air distribution system may also include an air return duct 18, an air supply duct 20, and / or an air handler 22. In some embodiments, the air handler 22 may include a heat exchanger connected to the boiler 16 and the vapor compression system 14 by a conduit 24. The heat exchanger in the air handler 22 may receive either heated liquid from the boiler 16 or chilled liquid from the vapor compression system 14 depending on the operating mode of the HVAC&R system 10. Although HVAC&R system 10 is shown with a separate air handler on each floor of building 12, in other embodiments, HVAC&R system 10 may include air handlers 22 and / or other components that may be shared between floors.

[0018] 2 and 3 are an embodiment of a vapor compression system 14 that may be used within HVAC&R system 10. Vapor compression system 14 may circulate a refrigerant through a circuit that begins with a compressor 32. The circuit may also include a condenser 34, an expansion valve or device 36, and a liquid chiller or evaporator 38. Vapor compression system 14 may further include a control panel 40 having an analog-to-digital (A / D) converter 42, a microprocessor 44, non-volatile memory 46, and / or an interface board 48.

[0019] Some examples of fluids that may be used as refrigerants in the vapor compression system 14 are hydrofluorocarbon (HFC)-based refrigerants, e.g., R-410A, R-407, R-134a, R-1233zd, R-1234ze, hydrofluoroolefins (HFOs), ammonia (NH3), R-717, carbon dioxide (CO2), R-744, or "natural" refrigerants such as hydrocarbon-based refrigerants, water vapor, or any other suitable refrigerant. In some embodiments, the vapor compression system 14 may be configured to efficiently utilize refrigerants having a normal boiling point of about 19 degrees Celsius (66 degrees Fahrenheit) at one atmosphere pressure, also referred to as low pressure refrigerants, as compared to medium pressure refrigerants such as R-134a. As used herein, "normal boiling point" may refer to the boiling point temperature measured at one atmosphere pressure.

[0020] In some embodiments, the vapor compression system 14 may use one or more of a variable speed drive (VSD) 52, a motor 50, a compressor 32, a condenser 34, an expansion valve or device 36, and / or an evaporator 38. The motor 50 may drive the compressor 32 and may be powered by the variable speed drive (VSD) 52. The VSD 52 receives AC power having a particular fixed line voltage and fixed line frequency from an alternating current (AC) source and provides power having a variable voltage and frequency to the motor 50. In other embodiments, the motor 50 may be powered directly from an AC source or a direct current (DC) source. The motor 50 may include any type of motor that may be powered by a VSD or directly from an AC source or a DC source, such as a switched reluctance motor, an induction motor, an electronically commutated permanent magnet motor, or another suitable motor.

[0021] The compressor 32 compresses a refrigerant vapor and delivers the vapor to the condenser 34 through a discharge passage. In some embodiments, the compressor 32 may be a centrifugal compressor. The refrigerant vapor delivered by the compressor 32 to the condenser 34 may transfer heat to a cooling fluid (e.g., water or air) in the condenser 34. The refrigerant vapor may condense into a refrigerant liquid in the condenser 34 as a result of the heat transfer with the cooling fluid. The liquid refrigerant from the condenser 34 may flow through the expansion device 36 to the evaporator 38. In the illustrated embodiment of FIG. 3, the condenser 34 is water-cooled and includes a tube bundle 54 connected to a cooling tower 56 that supplies cooling fluid to the condenser 34.

[0022] The liquid refrigerant delivered to the evaporator 38 may absorb heat from another cooling fluid, which may or may not be the same cooling fluid used in the condenser 34. The liquid refrigerant in the evaporator 38 may undergo a phase change from liquid refrigerant to a refrigerant vapor. As shown in the illustrated embodiment of FIG. 3, the evaporator 38 may include a tube bundle 58 having a supply line 60S and a return line 60R connected to a cooling load 62. The cooling fluid of the evaporator 38 (e.g., water, ethylene glycol, calcium chloride brine, sodium chloride brine, or any other suitable fluid) enters the evaporator 38 via the return line 60R and exits the evaporator 38 via the supply line 60S. The evaporator 38 may reduce the temperature of the cooling fluid in the tube bundle 58 through heat transfer with the refrigerant. The tube bundle 58 in the evaporator 38 may include multiple tubes and / or multiple tube bundles. In any case, the vapor refrigerant exits the evaporator 38 and returns to the compressor 32 by a suction line to complete the cycle.

[0023] FIG. 4 is a schematic diagram of a vapor compression system 14 having an intermediate circuit 64 incorporated between the condenser 34 and the expansion device 36. The intermediate circuit 64 may have an inlet line 68 directly fluidly connected to the condenser 34. In other embodiments, the inlet line 68 may be indirectly fluidly coupled to the condenser 34. As shown in the illustrated embodiment of FIG. 4, the inlet line 68 includes a first expansion device 66 positioned upstream of an intermediate vessel 70. In some embodiments, the intermediate vessel 70 may be a flash tank (e.g., a flash intercooler, an economizer, etc.). In other embodiments, the intermediate vessel 70 may be configured as a heat exchanger or a "surface economizer." In the illustrated embodiment of FIG. 4, the intermediate vessel 70 is used as a flash tank, and the first expansion device 66 is configured to reduce the pressure (e.g., expand) of the liquid refrigerant received from the condenser 34. During the expansion process, a portion of the liquid may be vaporized and thus, intermediate vessel 70 may be used to separate the vapor from the liquid received from first expansion device 66 .

[0024] Additionally, the intermediate vessel 70 may provide further expansion of the liquid refrigerant due to the pressure drop the liquid refrigerant experiences as it enters the intermediate vessel 70 (e.g., due to the sudden increase in volume it experiences as it enters the intermediate vessel 70). The vapor in the intermediate vessel 70 may be drawn by the compressor 32 through a suction line 74 (e.g., an interstage line) of the compressor 32. In other embodiments, the vapor in the intermediate vessel may be drawn into an intermediate stage of the compressor 32 (e.g., rather than a suction stage). The liquid that collects in the intermediate vessel 70 may be of lower enthalpy than the liquid refrigerant exiting the condenser 34 due to expansion in the expansion device 66 and / or the intermediate vessel 70. The liquid from the intermediate vessel 70 may then flow in line 72 through the second expansion device 36 to the evaporator 38.

[0025] It should be appreciated that any of the features described herein may be incorporated into vapor compression system 14 or any other suitable HVAC&R system. For example, the present technology may be incorporated into an HVAC&R system having an economizer, such as intermediate vessel 70, and a compressor, such as compressor 32. The following discussion describes the present technology as incorporated into an embodiment of compressor 32 configured as a single stage compressor. However, it should be noted that the systems and methods described herein may be incorporated into other embodiments of compressor 32 and HVAC&R system 10.

[0026] As discussed above, the present disclosure is directed to systems and methods for adjusting an impeller of a compressor to achieve and / or maintain a desired position of the impeller within a housing of the compressor. For example, a distance between a surface of the impeller and a housing of the compressor can be detected and / or monitored. A position of the impeller can be adjusted based on a determination that the distance is not equal to a predetermined distance value and / or is outside a range of distance values ​​associated with a desired position of the impeller. For example, the impeller can be coupled to a shaft, and a position of the shaft can be adjusted to adjust the distance between the surface of the impeller and the housing to be within a range of distance values. In other words, the position of the shaft can be controlled to maintain the distance between the surface of the impeller and the housing within a range of distance values ​​and / or to be approximately equal to a predetermined distance value. In this manner, the present technology allows for the position of the impeller to be adjusted to achieve alignment between an outlet of the impeller and an inlet of a diffuser passage of the compressor, thereby allowing for more efficient operation of the compressor.

[0027] With the above in mind, FIG. 5 is a side cross-sectional view of one embodiment of the compressor 32 of the HVAC&R system 10. The compressor 32 may include a housing 100 and a shaft 102 extending through the housing 100. The compressor 32 may also include an impeller 104 coupled to the shaft 102, such as via a fastener 106. During operation of the compressor 32, the shaft 102 may rotate (e.g., via operation of the motor 50), causing rotation of the impeller 104 within the housing 100. The rotation of the impeller 104 may drive a working fluid (e.g., refrigerant) to flow along a working fluid flow path 108 (e.g., from the evaporator 38, from the intermediate vessel 70), drawing the working fluid into the housing 100 via a suction inlet 110 and toward the impeller 104. The impeller 104 imparts mechanical energy to the working fluid and may discharge the working fluid through an impeller exit or outlet 114 of the impeller 104 towards a diffuser passage 112 of the compressor 32. The working fluid may be directed from the diffuser passage 112 to a volute 116 of the compressor 32 and from the volute 116 to another component of the HVAC&R system 10 (e.g., the condenser 34) for heat exchange with a fluid, such as a cooling fluid.

[0028] In the illustrated embodiment, the compressor 32 includes a first bearing 118 (e.g., an axial bearing, a thrust bearing, a magnetic thrust bearing) configured to control and / or adjust a position (e.g., an axial position) of the shaft 102 along an axis 120 (e.g., a longitudinal axis, an axis of rotation of the shaft 102) that extends along the length of the compressor 32. For example, the first bearing 118 may be configured to prevent or limit movement (e.g., translation) of the shaft 102 along and / or relative to the axis 120. The compressor 32 may also include a second bearing 122 (e.g., a first radial bearing) and a third bearing 124 (e.g., a second radial bearing). The second bearing 122 and the third bearing 124 may prevent movement (e.g., bending, radial movement, eccentric rotation) of the shaft 102 in a direction transverse to the axis 120.

[0029] In some embodiments, the first bearing 118 may be positioned at or coupled to a first end 126 (e.g., axial end, longitudinal end) of the shaft 102, and the impeller 104 may be positioned at or coupled to a second end 128 (e.g., axial end, longitudinal end) of the shaft 102 opposite the first end 126. Thus, the first bearing 118 and the impeller 104 may be positioned at opposite ends 126, 128 of the shaft 102. Additionally, in the illustrated embodiment, the second bearing 122 is positioned adjacent to the first bearing 118 at the first end 126 of the shaft 102, and the third bearing 124 is positioned adjacent to the impeller 104 at the second end 128 of the shaft 102. Positioning the impeller 104 and third bearing 124 at the second end 128 of the shaft 102 and the first bearing 118 and second bearing 122 at the first end 126 of the shaft 102 may enable desired rotation and / or other movement of the shaft 102. For example, the arrangement of the impeller 104, first bearing 118, second bearing 122, and third bearing 124 may enable stable (e.g., concentric) rotation of the shaft 102 and / or provide control of the respective positions of the impeller 104 and shaft 102 (e.g., relative to the housing 100), such as with a system in which the first bearing 118 is positioned more adjacent (e.g., at the second end 128) to the impeller 104. Additionally, the described arrangement of the illustrated embodiment may provide a more balanced weight and / or load distribution along the shaft 102, improving rotational stability of the shaft 102 and impeller 104 during operation of the compressor 32.

[0030] As discussed above, during operation of the compressor 32, the impeller 104 may be subject to changes in shape and / or position relative to the housing 100. As one example, rotation of the impeller 104 during operation of the compressor 32 may generate heat along the shaft 102, which may cause thermal growth and / or expansion of the shaft 102 (e.g., along the axis 120), which may drive the impeller 104 to move in a first direction 130 (e.g., a first axial direction) along the axis 120 relative to the housing 100. As another example, rotation of the impeller 104 may cause the blades 131 of the impeller 104 to bend, deflect, or flex toward a portion of the housing 100. That is, during higher rotational speeds of the impeller 104 (e.g., an unshrouded or open impeller), the blades 131 may bend, pivot, rotate, or otherwise deflect outward (e.g., relative to or along the axis 120). In either example, one or more surfaces of the impeller 104 (e.g., blade surfaces, shroud-facing surfaces, top surfaces) may move or shift at least partially in the first direction 130 relative to the housing 100.

[0031] As will be appreciated, it may be desirable to limit, reduce, and / or adjust movement of the impeller 104 along the axis 120, such as in response to movement or shifting of the impeller 104 within the housing 100 that may be induced during operation of the compressor 32. As an example, movement of the impeller 104 along the axis 120 may cause misalignment of the impeller outlet 114 and the diffuser passage 112 (e.g., relative to the direction of flow of the working fluid therethrough). Additionally, movement of the impeller 104 along the axis 120 may reduce a distance (e.g., clearance) between the impeller 104 and a portion of the housing 100. For example, movement of the impeller 104 along the first direction 130 may position the impeller 104 closer to a shroud-containing portion 132 (e.g., stationary portion, impeller-containing portion, blade-containing portion, nozzle plate-containing portion) of the housing 100. Such movement may adversely affect the performance and / or structural integrity of the compressor 32. For example, movement of the impeller 104 in the first direction 130 may cause contact between the impeller 104 (e.g., the shroud of the impeller 104, the blades 131 of the impeller 104) and the shroud housing portion 132, which may cause wear or deterioration of the impeller 104 and / or the housing 100. It may also be desirable to limit (e.g., reduce) the amount of distance (e.g., clearance) between the impeller 104 and the shroud housing portion 132 of the housing 100 to facilitate improved (e.g., more efficient) operation of the compressor 32.

[0032] Thus, the HVAC&R system 10 may include a control system 134 (e.g., a controller, an automation controller, an electronic controller, a magnetic bearing controller) configured to operate the compressor 32 to mitigate and / or adjust movement of the impeller 104 along the axis 120. For example, the control system 134 may be configured to monitor and / or adjust the position of the impeller 104 within the housing 100 to mitigate misalignment of the impeller outlet 114 and the diffuser passage 112. The control system 134 may include a memory 136 and a processing circuit 138 (e.g., a microprocessor). The memory 136 may include volatile memory, such as random access memory (RAM), and / or non-volatile memory, such as read-only memory (ROM), an optical drive, a hard disk drive, a solid-state drive, or any other tangible, non-transitory computer-readable medium that, when executed by the processing circuit 138, controls the operation of the compressor 32. The processing circuit 138 may be configured to execute the instructions stored in the memory 136. As an example, processing circuitry 138 may include one or more application specific integrated circuits (ASICs), one or more field programmable gate arrays (FPGAs), one or more general purpose processors, or any combination thereof. Processing circuitry 138 may include multiple microprocessors, one or more "general purpose" microprocessors, one or more special purpose microprocessors, and / or some combination thereof. For example, processing circuitry 138 may include one or more reduced instruction set (RISC) processors.

[0033] The control system 134 may be configured to enable adjustment of the position (e.g., axial position) of the impeller 104 along the axis 120 and / or relative to the housing 100. By way of example, the control system 134 may be configured to enable adjustment of the position of the shaft 102 along the axis 120 to drive (e.g., adjust the position) of the impeller 104 along the axis 120. In some embodiments, the compressor 32 may include a collar 140 (e.g., a thrust collar) fixedly coupled to the shaft 102. Thus, movement of the collar 140 may cause corresponding movement of the shaft 102. The first bearing 118 may control the movement of the collar 140, and thus the movement (e.g., axial movement) of the shaft 102 and impeller 104, along the axis 120. For example, the first bearing 118 may be a magnetic bearing assembly including a first magnetic bearing component or portion 142 (e.g., first magnetic winding, first electromagnet) and a second magnetic bearing component or portion 144 (e.g., second magnetic winding, second electromagnet). The collar 140 may be positioned between (e.g., axially therebetween with respect to the axis 120) the magnetic bearing components 142, 144, and each of the magnetic bearing components 142, 144 may impart a magnetic force to the collar 140 to adjust the position of the collar 140 along the axis 120. For example, the magnetic bearing components 142, 144 may have magnetic poles (e.g., forward poles, reverse poles) that impart a magnetic force to the collar 140.

[0034] In some cases, during operation of the compressor 32, the magnetic forces imparted by the magnetic bearing components 142, 144 may prevent movement of the collar 140 along the axis 120. For example, the control system 134 may be configured to control the first bearing 118 to prevent movement of the collar 140 along the axis 120 to maintain alignment (e.g., radial alignment with respect to the axis 120) of the impeller outlet 114 and the diffuser passage 112. However, the collar 140, and thus the shaft 102, may be free to rotate (e.g., via the motor 50) to drive rotation of the impeller 104. In some embodiments, the magnitude of the magnetic forces (e.g., total magnetic force) imparted to the collar 140 by one or both of the magnetic bearing components 142, 144 may be adjustable. As an example, the magnetic force (e.g., the total magnetic force applied to the collar 140) may be increased to compensate for adjustment and / or movement of a portion of the shaft 102 (e.g., at the second end 128) that may occur as a result of thermal growth during operation of the compressor 32. In other words, the thermal growth may cause the shaft 102 to move undesirably in a particular direction (e.g., the first direction 130), and a magnetic force may be applied to the collar 140 via the magnetic bearing components 142, 144 to cause the shaft 102 to move in a direction opposite the particular direction (e.g., opposite the first direction 130) to reduce or mitigate the overall movement of the shaft 102, for example, preventing movement of the shaft 102 toward the shroud-receiving portion 132.

[0035] The control system 134 may be communicatively coupled to the first bearing 118 and may also be configured to control the movement and / or positioning of the collar 140, and thus the shaft 102, along the axis 120 via the magnetic bearing components 142, 144. For example, the control system 134 may be configured to adjust the current provided to the magnetic bearing components 142, 144 to adjust the magnetic force (e.g., overall magnetic force, electromagnetic force, magnetic field) imparted to the collar 140. The position (e.g., axial position) of the collar 140 between the magnetic bearing components 142, 144 may be adjusted by varying the magnetic force imparted to the collar 140, e.g., by pushing and / or pulling the collar 140 along the axis 120 via the magnetic force.

[0036] In some embodiments, the compressor 32 may include one or more sensors communicatively coupled to the control system 134 and configured to detect one or more operating parameters of the compressor 32. The control system 134 may adjust the operation of the first bearing 118 based on feedback and / or data from the one or more sensors. For example, the compressor 32 may include a first sensor 146 (e.g., a proximity sensor, a position sensor, a capacitance sensor) configured to monitor an operating parameter indicative of an axial position of the impeller 104 (e.g., along the axis 120, relative to the housing 100). The first sensor 146 may transmit sensor data indicative of the operating parameter to the control system 134, which may control the first bearing 118 (e.g., magnetic bearing components 142, 144) to adjust the position of the collar 140 based on the sensor data received from the first sensor 146. As an example, the control system 134 may control the first bearing 118 to maintain a desired axial position of the collar 140, and thus the impeller 104, along the axis 120. In some embodiments, the control system 134 may control the first bearing 118 to maintain a desired axial position of the collar 140 related to or corresponding to the alignment of the impeller outlet 114 and the diffuser passage 112.

[0037] The compressor 32 may also include a second sensor 148 configured to monitor a position of the collar 140, such as relative to the magnetic bearing components 142, 144 (e.g., along the axis 120). The second sensor 148 may transmit sensor data indicative of the position of the collar 140 to the control system 134, which may control operation of the first bearing 118 to adjust the position of the collar 140 based on the sensor data received from the second sensor 148. For example, the control system 134 may control the first bearing 118 to maintain the position of the collar 140 within a predetermined range of positions of the collar 140. In some embodiments, the predetermined range of positions of the collar 140 may correspond to an alignment of the impeller outlet 114 and the diffuser passage 112. By controlling the magnetic bearing components 142, 144 to maintain the collar 140 within the predetermined range of positions of the collar, contact between the collar 140 and the magnetic bearing components 142, 144 may be avoided. As an example, the control system 134 may control the first bearing 118 to maintain a desired axial position of the impeller 104 without moving the collar 140 outside a predetermined range of collar positions. The control system 134 may be configured to control the first bearing 118 to drive the collar 140 and the impeller 104 to move in a first direction 130 along the axis 120 and / or in a second direction 150 (e.g., a second axial direction) opposite the first direction 130 along the axis 120. In practice, the control system 134 may control the first bearing 118 based on sensor data received (e.g., from the first sensor 146, from the second sensor 158) during operation of the compressor 32. In some embodiments, the control system 134 may control the first bearing 118 based on additional or alternative data and / or feedback (e.g., received from additional sensors), such as data indicative of the operating capacity of the compressor 32, the speed of the compressor 32, the pressure of the working fluid circulated by the compressor 32, the flow rate of the working fluid circulated by the compressor 32, another suitable operating parameter, or any combination thereof.Thus, the control system 134 can dynamically adjust the position of the collar 140 and impeller 104 in real time during operation of the compressor 32 (e.g., during rotation of the shaft 102 and / or impeller 104) via control of the first bearing 118 to maintain the impeller 104 in a desired position. Indeed, it should be appreciated that in accordance with the present techniques, the control system 134 may be utilized in conjunction with any of the embodiments and / or features of the compressor 32 described herein to enable a desired positioning of the impeller 104.

[0038] 6 is a side cross-sectional view of an embodiment of a portion of the compressor 32. The compressor 32 includes similar elements and element numbering as described above. The diffuser passage 112 of the compressor 32 may be defined at least in part by a shroud receiving portion 132 of the housing 100 and a hub receiving portion 202 of the housing 100. The shroud receiving portion 132 may be configured to surround a portion of the impeller 104. For example, the impeller 104 may include a shroud 204, which may be integral with and / or connected to the blades 131 of the impeller 104. In particular, the shroud 204 may include a blade facing surface 200 connected to the blades 131 of the impeller 104. In fact, the position of the shroud 204 may be fixed relative to the positions of the blades 131 such that rotation of the blades 131 causes a corresponding rotation of the shroud 204 and / or such that axial movement (e.g., along the axis 120) of the blades 131 causes a corresponding axial movement of the shroud 204. The shroud housing portion 132 may surround or enclose at least a portion of the shroud 204 and the blades 131. The hub housing portion 202 may be configured to surround another portion of the impeller 104. For example, the impeller 104 may include a hub 206 that may be attached to the shaft 102, and the hub housing portion 202 may surround or enclose at least a portion of the hub 206.

[0039] In the illustrated embodiment, the first sensor 146 (e.g., a proximity sensor) is coupled to and extends through the shroud housing portion 132. For example, the impeller 104 may be positioned within the housing 100 to provide a gap or space 208 between a surface 210 (e.g., an outer surface, an outer shroud surface, a machined surface, a planar surface) of the shroud 204 and the shroud housing portion 132. A hole 212 (e.g., an opening, a passage) may be formed in the shroud housing portion 132 and may extend to the gap 208, and the first sensor 146 may be inserted through the hole 212 and exposed to the gap 208. Thus, the first sensor 146 may detect a distance (e.g., an axial distance along the axis 120) between the surface 210 and the shroud housing portion 132. By way of example, the first sensor 146 may include a non-contact sensor, such as an eddy current sensor, a capacitive sensor, an optical sensor, an ultrasonic sensor, an inductive sensor, a Hall effect sensor, and / or other suitable types of sensors. The first sensor 146 may be sealably positioned within the bore 212, such as via a seal positioned within and / or adjacent to the bore 212 (e.g., around the first sensor 146). That is, the first sensor 146 and / or the seal may block working fluid from flowing through the bore 212 between the first sensor 146 and the shroud housing portion 132, thereby maintaining the flow of working fluid through the impeller 104 and the diffuser passage 112.

[0040] To facilitate detection and / or measurement of the gap 208 (e.g., the size of the gap 208 extending from the shroud housing portion 132 and / or the first sensor 146 to the surface 210) via the first sensor 146, the surface 210 may be planar (e.g., flat) and / or may extend along the circumference of the impeller 104. In this manner, a more accurate and / or more representative detection of the distance (e.g., average distance) between the surface 210 and the shroud housing portion 132 by the first sensor 146 during rotation of the impeller 104 about the axis 120 is enabled. That is, the distance measured by the first sensor 146 based on detection of the surface 210 may provide a better (e.g., more accurate, more reliable) indication of the position of the impeller 104 relative to the housing 100 (e.g., the shroud housing portion 132). For example, such a configuration of surface 210 may reduce changes in detected distance caused by variations in the contour (e.g., curvature) of impeller 104 and / or other potential factors unrelated to movement of impeller 104 relative to housing 100 (e.g., along axis 120), which may affect the detection and / or measurement of the distance between surface 210 and shroud housing portion 132. In this manner, the data and / or feedback (e.g., distance data) provided by first sensor 146 to control system 134 may enable more appropriate and reliable operation of control system 134 to adjust the position of impeller 104.

[0041] As will be appreciated, it may be desirable to align the impeller outlet 114 of the impeller 104 with the diffuser passage 112 to facilitate more efficient flow of the working fluid through the compressor 32. For example, it may be desirable to align the first central axis 216 of the impeller outlet 114 with the second central axis 218 of the diffuser passage 112. Maintaining alignment between the impeller outlet 114 and the diffuser passage 112 may reduce or mitigate pressure losses and / or flow losses associated with the flow of the working fluid, such as due to friction (e.g., between the working fluid and the shroud housing portion 132, between the working fluid and the hub housing portion 202) and / or other undesired (e.g., turbulent) flow of the working fluid. In this manner, maintaining alignment of the impeller outlet 114 and the diffuser passage 112 facilitates more efficient operation of the compressor 32. However, during operation of the compressor 32, the impeller 104 may shift (e.g., along the axis 120) causing the impeller outlet 114 and the diffuser passage 112 to become misaligned (e.g., the first central axis 216 and the second central axis 218 to become misaligned).

[0042] Thus, in accordance with the present technique, the control system 134 is configured to monitor, adjust, and / or otherwise control the axial position (e.g., along the axis 120) of the impeller 104 to enable alignment of the impeller outlet 114 and the diffuser passage 112. The distance between the surface 210 and the shroud housing portion 132 may indicate alignment and / or misalignment between the impeller outlet 114 and the diffuser passage 112. The control system 134 may monitor and adjust the axial position of the impeller 104 (e.g., via control of the first bearing 118, the thrust bearing) to control, adjust, and / or maintain the distance between the surface 210 and the shroud housing portion 132, e.g., to maintain the distance within a predetermined range of distance values. The predetermined range of distance values ​​may be associated with a desired positioning of the impeller outlet 114 relative to the diffuser passage 112 (e.g., corresponding to an acceptable or desired alignment of the first central axis 216 and the second central axis 218).

[0043] While the illustrated first sensor 146 is positioned within the shroud housing portion 132, in additional or alternative embodiments, the first sensor 146 may be positioned within the hub housing portion 202. In such embodiments, the first sensor 146 may be configured to detect a distance (e.g., an axial distance along the axis 120) between a surface (e.g., an axial surface) of the hub 206 and the hub housing portion 202, and the control system 134 may be configured to monitor, adjust, and / or otherwise control the axial position of the impeller 104 (e.g., via control of the first bearing 118) based on the distance between the surface of the hub 206 and the hub housing portion 202 detected by the first sensor 146.

[0044] It should be noted that in certain existing systems, the diffuser passage 112 may be shaped (e.g., tapered) to accommodate expected misalignment between the impeller outlet 114 and the diffuser passage 112 during operation of the compressor 32. For example, the shape of the diffuser passage 112 may be selected and / or configured to limit or mitigate losses (e.g., pressure loss, flow loss) of the working fluid upon misalignment between the impeller outlet 114 and the diffuser passage 112. In some embodiments, the shroud accommodating portion 132 may include a first tapered surface 220 (e.g., an inclined surface) that may extend obliquely relative to the second central axis 218 to provide a diffuser inlet 222 having a larger dimension (e.g., larger diameter, larger width along the axis 120) for the flow of working fluid through the diffuser passage 112 than the dimension of the diffuser passage 112 downstream of the diffuser inlet 222. Additionally or alternatively, the diffuser inlet 222 can have a larger dimension (e.g., a larger diameter, a larger width along the axis 120) than the dimension of the impeller outlet 114. In additional or alternative embodiments, the hub housing portion 202 can include a second tapered surface 224 that extends obliquely relative to the second central axis 218 to provide the diffuser inlet 222 with a relatively larger dimension.

[0045] The tapered shape of the diffuser passage 112 described above may cause relatively increased losses (e.g., compared to a diffuser passage 112 not having such a tapered shape) when the impeller outlet 114 and the diffuser passage 112 are aligned with one another (e.g., during alignment of the first central axis 216 and the second central axis 218). Thus, in existing systems, the operating efficiency of the compressor 32 may be prone to decrease when the impeller outlet 114 and the diffuser passage 112 are aligned. Controlling (e.g., adjusting) the axial position of the impeller 104 to maintain a rough and / or intended alignment between the impeller outlet 114 and the diffuser passage 112 may allow the diffuser passage 112 to be manufactured with a reduced shaping (e.g., taper) that is otherwise intended to accommodate expected misalignment of the impeller outlet 114 and the diffuser passage 112.

[0046] Embodiments of the present disclosure may include a diffuser passage 112 having a non-tapered or generally straight shape (e.g., along the first central axis 216). For example, instead of having tapered surfaces 220, 224, the shroud accommodation portion 132 and / or the hub accommodation portion 202 may have surfaces defining the diffuser passage 112 that extend radially from the impeller outlet 114 relative to the axis 120 (e.g., generally parallel to the first central axis 216 and / or the second central axis 218). As an example, the surface of the hub accommodation portion 202 may extend radially (e.g., completely radially) relative to the axis 120, and the surface of the shroud accommodation portion 132 may be tapered (e.g., the first tapered surface 220). As another example, the surface of the shroud accommodating portion 132 may extend radially (e.g., completely radially) relative to the axis 120, and the surface of the hub accommodating portion 202 may be tapered (e.g., the second tapered surface 224). The radial expansion of the surface of the shroud accommodating portion 132 and / or the surface of the hub accommodating portion 202 may facilitate reducing pressure loss and / or flow loss of the working fluid when the impeller outlet 114 and the diffuser passage 112 are aligned with one another, and thus may increase the operating efficiency of the compressor 32 while the impeller outlet 114 and the diffuser passage 112 are aligned. Additionally, manufacturing the impeller 104 in which the diffuser passage 112 has a non-tapered or generally straight shape may facilitate reducing costs associated with manufacturing the impeller 104.

[0047] FIG. 7 is a side cross-sectional view of some embodiments of the compressor 32. The compressor 32 may include certain similar elements and element numbers as described above. As shown, the first sensor 146 is positioned within the shroud receiving portion 132. Additionally, in the illustrated embodiment, the impeller 104 of the compressor 32 is shown as an unshrouded or partially unshrouded impeller 104 (e.g., without the shroud 204). Thus, the blades 131 of the impeller 104 are exposed to the shroud receiving portion 132. For example, the unshrouded impeller 104 of FIG. 7 may be lighter than a shrouded impeller such as the impeller 104 of FIG. 6, thus reducing the weight of the compressor 32. The reduced weight of the unshrouded impeller 104 may facilitate the manufacture, installation, transportation, maintenance, etc. of the compressor 32. Additionally or alternatively, the lighter, unshrouded impeller 104 can be controlled to rotate at a higher speed as compared to a heavier (e.g., shrouded) impeller. In some embodiments, the unshrouded impeller 104 can be manufactured at a reduced cost as compared to the impeller 104 of FIG. 6 having a shroud 204.

[0048] In an installed configuration of the impeller 104 within the housing 100, a gap or space 250 (e.g., clearance, clearance area) may extend between a blade tip or edge 252 (e.g., distal edge, distal surface, blade tip surface) of the blade 131 of the impeller 104 and the shroud housing portion 132 (e.g., an inner surface 260 of the shroud housing portion 132 facing the blade 131). The first sensor 146 may extend through the shroud housing portion 132 and be exposed to the gap 250 and / or the blade tip 252. Thus, the first sensor 146 may be configured to detect, measure, and / or monitor the distance between the blade tip 252 (e.g., a respective surface or edge of the blade tip 252) and the shroud housing portion 132. For example, during operation of the impeller 104, the blades 131 may bend, flex, deflect, or otherwise deform (e.g., relative to the hub 206). For example, the blades 131 may pivot or deflect outward (e.g., radially outward) relative to the shaft 120 and / or relative to the hub 206. Deflecting the blades 131 in this manner may reduce the size or magnitude of the gap 250 (e.g., clearance), which may increase the likelihood of contact between the blades 131 (e.g., blade tips 252) and the shroud housing portion 132. As an example, an increase in the rotational speed of the impeller 104 may impart a force (e.g., induced by contact between the blades 131 and the working fluid) to the blades 131, causing them to bend or deflect and reduce the size of the gap 250 (e.g., reducing the clearance between the blade tips 252 and the shroud housing portion 132). As another example, an increase in temperature of the impeller 104 (e.g., caused by increased operating temperatures caused by friction during operation of the compressor 32) may cause at least partial thermal expansion of the blades 131 in a direction toward the shroud housing portion 132, which may reduce the size or dimension of the gap 250. Indeed, an increase in rotational speed and / or an increase in temperature of the impeller 104 may reduce the size of the gap 250, thereby reducing the amount of clearance between the blade tips 252 and the shroud housing portion 132.

[0049] As such, the control system 134 is configured to adjust (e.g., in real time during operation of the compressor 32) the axial position of the impeller 104 such that the distance between the blade tips 252 and the shroud housing portion 132 is equal to or greater than a predetermined distance, thereby maintaining a desired amount of clearance (e.g., a desired size of the gap 250) between the blade tips 252 and the shroud housing portion 132. For example, the control system 134 may dynamically operate the magnetic bearing components 142, 144 of the first bearing 118 based on data and / or feedback, etc., to adjust the position (e.g., along the axis 120) of the coupled collar 140, shaft 102, and impeller 104 relative to the shroud housing portion 132. In some embodiments, the control system 134 may operate the first bearing 118 to adjust the position of the impeller 104 based on sensor data (e.g., from the first sensor 146). The first sensor 146 may detect the magnitude of the distance between the blade tip 252 and the shroud housing portion 132 and provide data or feedback indicative of the magnitude of the distance (e.g., the gap 250) to the control system 134. In response, the control system 134 may adjust the operation of the first bearing 118 based on the feedback indicative of the magnitude of the distance.

[0050] In some embodiments, the control system 134 may compare the magnitude of the distance detected by the first sensor 146 to a predetermined or threshold distance value (e.g., a threshold clearance value) or range of threshold distance values, which may be stored in the memory 136, and adjust the position of the impeller 104 (e.g., via control of the first bearing 118) based on the comparison. In some cases, the threshold distance value may be associated, correlated, and / or correspond to a position of the impeller 104 where the impeller outlet 114 and the diffuser passage 112 are aligned with one another. Thus, the present techniques may enable more efficient operation of the compressor 32 (e.g., more efficient flow of working fluid, reduced pressure drop, etc.). Additionally or alternatively, the threshold distance value (e.g., stored in the memory 136) may be associated, correlated, and / or correspond to a desired magnitude of the distance between the blade tip 252 and the shroud housing portion 132. In some embodiments, the control system 134 may control the first bearing 118 to maintain the distance between the blade tip 252 and the shroud housing portion 132 within a predetermined range of distance values ​​associated with a desired positioning of the impeller 104 within the housing 100 (e.g., relative to the shroud housing portion 132).

[0051] Thus, the control system 134 can control the first bearing 118, thereby controlling and / or adjusting the position of the impeller 104 to prevent potential contact between the blade tips 252 and the shroud housing portion 132. In this manner, the present technique facilitates maintaining the structural integrity of the blade tips 252 and the shroud housing portion 132. The present technique also facilitates implementation and / or operation of the impeller 104 without a shroud, such as at different rotational speeds of the impeller 104 and / or at different operating temperatures associated with the compressor 32.

[0052] In the illustrated embodiment, the shroud housing portion 132 extends along a profile of the impeller 104, e.g., along the blade tips 252 and / or along a profile defined by the blade tips 252. As such, the first sensor 146 may be disposed at any suitable position or orientation within the shroud housing portion 132 and extend toward the gap 250 at any suitable angle relative to the axis 120, etc. Additionally or alternatively, the first sensor 146 may be positioned within (e.g., extending into) the hub housing portion 202 and configured to monitor a distance (e.g., along the axis 120) between the surface 254 of the hub 206 and the hub housing portion 202. Thus, the control system 134 may be configured to control the axial position of the impeller 104 based on the distance between the surface 254 of the hub 206 and the hub housing portion 202 in a manner similar to that described above.

[0053] 8 is a side cross-sectional view of an embodiment of a portion of the compressor 32. In the illustrated embodiment, the first sensor 146 is positioned within the shroud housing portion 132. The impeller 104 also includes a shroud 204. Additionally, the hub 206 of the impeller 104 includes a wall 270 that extends downstream of the impeller outlet 114 relative to the flow of working fluid through the impeller outlet 114. In other words, the impeller outlet 114 may be generally defined as a port or outlet of the impeller 104 that extends from a radially outer edge 272 (e.g., a distal end) of the shroud 204 to the wall 270 (e.g., along the axis 120), and the wall 270 may extend downstream of the impeller outlet 114 (e.g., toward and / or along the diffuser passage 112).

[0054] As shown, the first sensor 146 extends through the shroud housing portion 132 and is exposed to the diffuser passage 112. In other words, the first sensor 146 extends through the shroud housing portion 132 and is positioned downstream of the impeller outlet 114 and / or the radially outer edge 272 of the shroud 204 (e.g., with respect to the flow of working fluid through the impeller 104). Thus, the first sensor 146 may be positioned to detect a wall 270 of the hub 206 (e.g., along the axis 120). That is, the wall 270 may be exposed to and detected by the first sensor 146. For example, the first sensor 146 may detect a distance between a surface 274 of the wall 270 and the shroud housing portion 132. The surface 274 may also be exposed to the flow of working fluid. As also described above, the distance between the surface 274 of the wall 270 and the shroud housing portion 132 may indicate a position of the impeller 104 relative to the housing 100, such as an alignment between the impeller outlet 114 and the diffuser passage 112 and / or a distance between the impeller 104 (e.g., blade tips 252, shroud 204) and the shroud housing portion 132. In a similar manner as described above, the control system 134 may control the axial position of the impeller 104 (e.g., along the axis 120 via control of the first bearing 118) to control, adjust, and / or maintain the distance between the wall 270 and the shroud housing portion 132 (e.g., the distance between the shroud 204 or blade tips 252 and the shroud housing portion 132). For example, the control system 134 can adjust the position of the impeller 104 so that the distance from the wall 270 (e.g., the surface 274) to the shroud accommodating portion 132 (e.g., the first sensor 146) is within a predetermined range of distance values ​​associated with a desired positioning of the impeller 104 relative to the housing 100 (e.g., alignment of the impeller outlet 114 relative to the diffuser passage 112, alignment of the first central axis 216 and the second central axis 218).

[0055] In additional or alternative embodiments, the first sensor 146 may be configured to detect a different surface of the impeller 104, e.g., another surface exposed to the flow of working fluid directed through the impeller 104. For example, the shroud 204 may include a wall (e.g., similar to the wall 270) that extends downstream of the impeller outlet 114 relative to the flow of working fluid through the diffuser passage 112, and the first sensor 146 may be positioned within and extend through the hub housing portion 202. In such an embodiment, the first sensor 146 may be configured to detect a distance between a surface of the wall of the shroud 204 and the hub housing portion 202. In such an embodiment, the control system 134 may be configured to control the axial position of the impeller 104 (e.g., via control of the first bearing 118) based on the distance between the wall of the shroud 204 and the hub housing portion 202 to achieve a desired alignment of the impeller outlet 114 and the diffuser passage 112.

[0056] 9 is a flow chart of one embodiment of a method 300 for adjusting the position of the impeller 104. In some embodiments, the method 300 may be performed by a single respective component or system, such as the control system 134 (e.g., processing circuitry 138). In additional or alternative embodiments, multiple components or systems may perform the steps of the method 300. It should also be noted that additional steps may be performed with respect to the method 300. Additionally, certain steps of the depicted method 300 may be eliminated, modified, and / or performed in a different order than that shown in FIG.

[0057] At block 302, a value of an operating parameter indicative of a position of the impeller 104 may be received. For example, the value of the operating parameter (e.g., data indicative of the value) may be detected by the first sensor 146 and received from the first sensor 146 by the control system 134. In some embodiments, the operating parameter may include a distance from a surface 210 of the shroud 204 to the housing 100 (e.g., the shroud housing portion 132, the inner surface 260 of the shroud housing portion 132). In additional or alternative embodiments, the operating parameters may include the distance from the blade tips 252 to the housing 100 (e.g., the shroud receiving portion 132, the inner surface 260 of the shroud receiving portion 132), the distance from the surface 254 of the hub 206 to the housing 100 (e.g., the hub receiving portion 202), the distance from the wall 270 of the impeller 104 to the housing 100 (e.g., the shroud receiving portion 132), and / or the distance from any other portion of the impeller 104 to the housing 100. Indeed, the operating parameters may be indicative of the size or dimension of the gap 250 (e.g., clearance) between the impeller 104 and the housing 100. The operating parameters may also be indicative of the alignment of the impeller outlet 114 with respect to the diffuser passage 112.

[0058] At block 304, the value of the operating parameter may be compared (e.g., by the control system 134) to a predetermined value, threshold, and / or range of values, which may be stored in the memory 136. The predetermined value, threshold, and / or range of values ​​may correspond to a desired position of the impeller 104. For example, the desired position may correspond to a desired alignment between the impeller outlet 114 and the diffuser passage 112 (e.g., alignment of the first central axis 216 and the second central axis 218). In some cases, the range of values ​​may include upper and lower thresholds (e.g., predetermined values) that define or correspond to a range of positions of the impeller 104 that provide acceptable alignment of the impeller outlet 114 and the diffuser passage 112. Additionally or alternatively, the desired position may correspond to a desired distance (e.g., clearance) between the impeller 104 (e.g., shroud 204, blade tips 252) and the shroud housing portion 132 (e.g., inner surface 260).

[0059] In some embodiments, the predetermined value, threshold, and / or range of values ​​may be selected from a plurality of predetermined values, thresholds, and / or ranges of values ​​stored in memory 136. Selection of a particular predetermined value, threshold, and / or range of values ​​(e.g., by control system 134) may be based on another operating parameter of compressor 32 present or detected at the time of comparison, such as a dimension associated with impeller 104 (e.g., diameter, size of impeller outlet 114), operating capacity of compressor 32, rotational speed of impeller 104, temperature and / or pressure of working fluid (e.g., suction temperature and / or pressure), type of working fluid, temperature of shaft 102, another suitable operating parameter, and / or any combination thereof. In some applications, one or more of the predetermined values, thresholds, and / or ranges of values ​​may be calibration values ​​that correspond to a desired position of impeller 104, as described herein.

[0060] At block 306, the position of the impeller 104 within the housing 100 may be adjusted (e.g., via the control system 134) in response to comparing the value (e.g., detected by the first sensor 146) to a predetermined value, threshold, and / or range of values. By way of example, the current transmitted to the magnetic bearing components 142, 144 may be adjusted by the control system 134 to adjust the magnetic force imparted to the collar 140 to adjust the axial position of the collar 140 (e.g., along the axis 120) and accordingly adjust the axial position of the shaft 102 and impeller 104. For example, the axial position of the impeller 104 may be adjusted to maintain the value of the operating parameter (e.g., detected by the first sensor 146) within the range of values ​​and / or to adjust the value of the operating parameter to be within the range of values. Similarly, the axial position of the impeller 104 may be adjusted to maintain the value of the operating parameter (e.g., as detected by the first sensor 146) approximately equal to a predetermined value or threshold and / or to adjust the value of the operating parameter to approach and approximately equal to a predetermined value or threshold. Indeed, the method 300 described herein may be implemented to achieve a particular (e.g., desired, minimum, minimum acceptable) distance or size of the gap 250 (e.g., clearance) between the impeller 104 and the housing 100. In this manner, the method 300 may enable more efficient operation (e.g., reduced losses, improved performance) of the compressor 32 and / or more desirable positioning between the impeller 104 and the shroud housing portion 132 during variable operating conditions of the compressor 32.

[0061] It should be noted that the method 300 may be performed repeatedly (e.g., continuously) during operation of the compressor 32. For example, values ​​of the operating parameters may be received from the first sensor 146 and by the control system 134 at a desired frequency (e.g., several kilohertz) or interval for comparison to predetermined values, thresholds, and / or ranges of values. As a result of the comparison, the position of the impeller 104 may be adjusted or maintained accordingly utilizing the presently disclosed techniques. The techniques described herein may also be utilized to account for and / or compensate for other variable parameters of the compressor 32, such as variable working fluid conditions, manufacturing tolerances, and the like. Additionally, in some cases, the method 300 may be utilized to evaluate (e.g., in real time) the performance of the compressor 32 at various operating conditions and / or with the impeller 104 positioned at different positions within the housing 100. For example, the control system 134 may adjust the position of the impeller 104 relative to the shroud housing portion 132, and the control system 134 may receive feedback from other sensors in the HVAC&R system 10 indicative of the performance of the compressor 32 and / or the HVAC&R system 10 to evaluate changes in performance caused by the change in position of the impeller 104.

[0062] The present disclosure may provide one or more technical effects useful in the operation of an HVAC&R system. For example, an HVAC&R system may include a compressor having an impeller disposed within a housing. The impeller may rotate to compress a working fluid flow and direct the working fluid flow through the impeller to a diffuser passage. During operation of the compressor, the relative positioning of the impeller and the housing may be adjusted. For example, the shape and / or position of the impeller may change as a result of thermal growth of a shaft to which the impeller is connected. As another example, the shape of the impeller, e.g., the blades of an unshrouded impeller, may change at different rotational speeds of the impeller. Thus, a distance between a surface of the impeller (e.g., a surface of the impeller shroud, tips of the impeller blades, a surface of the impeller wall) and the housing may be detected and monitored. A control system may receive data indicative of the detected distance and may compare the detected distance to a particular value or range of values ​​associated with a desired position of the impeller. In response to the comparison, the control system can adjust the position of the impeller so that the detected distance approaches and / or is approximately equal to and / or within a range of a predetermined value. In particular, the impeller can be coupled to a shaft, and the position of the shaft can be adjusted (e.g., via control of a thrust bearing) to adjust a desired position of the impeller relative to the housing. Adjusting the position of the impeller can enable a desired alignment between the outlet of the impeller and the opening of the diffuser passage and / or provide a desired clearance between the impeller and the housing. Thus, a more efficient operation of the compressor can be achieved. The technical effects and technical problems herein are examples and are not limiting. It is noted that the embodiments described herein may have other technical effects and may solve other technical problems.

[0063] While only certain features and embodiments have been illustrated and described, those skilled in the art may conceive numerous modifications and changes, such as variations in the size, dimensions, structure, shape, and proportions of the various elements, parameter values ​​such as temperature and pressure, mounting arrangements, use of materials, colors, and orientations, etc., without substantially departing from the novel teachings and advantages of the subject matter recited in the claims. The order or sequence of any process or method steps may be modified or reordered in accordance with alternative embodiments. It is therefore to be understood that the appended claims are intended to cover all such modifications and changes that fall within the true spirit of the present disclosure.

[0064] Moreover, in order to provide a concise description of the exemplary embodiments, all features of an actual implementation may not be described, such as those that are not relevant to the currently contemplated best mode or that are not relevant to enabling. It will be appreciated that, as in any engineering or design project, many implementation-specific decisions may be made in the development of any such actual implementation. While such a development effort may be complex and time-consuming, it will nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill in the art having the benefit of this disclosure, without undue experimentation.

[0065] The technology presented and claimed herein refers to and applies to material objects and concrete examples of a practical nature that clearly improve the art, and is thus not abstract, intangible, or purely theoretical. Moreover, when any claim appended to the end of this specification includes one or more elements designated as "means for [performing] [a function]" or "steps for [performing] [a function]," it is intended that such elements be construed under 35 U.S.C. 112(f). However, for claims containing elements designated in any other manner, it is intended that such elements not be construed under 35 U.S.C. 112(f).

Claims

1. An HVAC&R system which is a heating, ventilation, air conditioning, and cooling system, comprising:

1. A compressor, comprising: Housing and a shaft disposed within the housing and extending through the housing; an impeller coupled to the shaft, the shaft configured to rotate about an axis relative to the housing to rotate the impeller; and A controller, receiving data indicative of a distance from a shroud of the impeller to the housing; a controller configured to adjust a position of the shaft along the axis based on a comparison of the distance from the shroud of the impeller to the housing and a predetermined value.

2. 2. The HVAC&R system of claim 1, further comprising a thrust bearing coupled to the shaft, the controller configured to adjust operation of the thrust bearing to adjust the position of the shaft along the axis.

3. 3. The HVAC&R system of claim 2, wherein the thrust bearing is positioned at a first end of the shaft and the impeller is coupled to a second end of the shaft opposite the first end.

4. 4. The HVAC&R system of claim 3, wherein the thrust bearing is a magnetic thrust bearing, and the controller is configured to adjust a current supplied to the magnetic thrust bearing to adjust the position of the shaft.

5. 2. The HVAC&R system of claim 1, further comprising a sensor communicatively coupled to the controller, the sensor configured to detect the distance from the shroud to the housing and transmit the data indicative of the distance to the controller, the controller configured to compare the distance to the predetermined value.

6. The HVAC&R system of claim 5 , wherein the sensor extends through a shroud receiving portion of the housing.

7. 7. The HVAC&R system of claim 6, wherein the sensor is configured to detect a surface of the shroud, the surface being planar and extending around a circumference of the impeller.

8. 2. The HVAC&R system of claim 1, wherein the predetermined value corresponds to an alignment of an outlet of the impeller with a diffuser passage in the housing downstream of the outlet with respect to a flow of working fluid through the compressor.

9. The HVAC&R system of claim 1 , wherein the predetermined value corresponds to a clearance between the impeller and a shroud-receiving portion of the housing.

10. The HVAC&R system of claim 1 , wherein said controller comprises a memory, and wherein said predetermined value is stored in said memory.

11. An HVAC&R system which is a heating, ventilation, air conditioning, and cooling system, comprising: A controller, receiving data from a sensor disposed within the compressor indicative of a distance from a shroud of an impeller to a housing of the compressor; Comparing the distance to a predetermined value; 11. An HVAC&R system comprising: a controller configured to adjust a position of a shaft coupled to the impeller along an axis of rotation of the shaft and adjust a position of the impeller relative to the housing based on a comparison of the distance from the shroud of the impeller to the housing and the predetermined value.

12. 12. The HVAC&R system of claim 11, wherein the predetermined value corresponds to an alignment of a first central axis of an outlet of the impeller with a second central axis of a diffuser passage of the housing downstream of the outlet with respect to a flow of working fluid through the compressor.

13. 12. The HVAC&R system of claim 11, wherein the controller is configured to adjust operation of a magnetic thrust bearing coupled to the shaft to adjust the position of the shaft.

14. The controller: comparing the distance to a range of values ​​that includes the predetermined value; 12. The HVAC&R system of claim 11 configured to adjust the position of the shaft and adjust the position of the impeller relative to the housing based on a comparison of the distance from the shroud of the impeller to the housing and the range of values.

15. The HVAC&R system of claim 11 including the sensor, the sensor configured to extend through a shroud receiving portion of the housing.

16. An HVAC&R system which is a heating, ventilation, air conditioning, and cooling system, comprising:

1. A compressor, comprising: Housing and a shaft disposed within the housing and extending through the housing; a thrust bearing disposed within the housing and coupled to the shaft; a compressor comprising: an impeller disposed within the housing and coupled to the shaft, the impeller comprising a plurality of blades and a shroud secured to the plurality of blades; a controller configured to control operation of the thrust bearing based on data indicative of a detected distance from the housing to the shroud of the impeller.

17. 17. The HVAC&R system of claim 16, wherein the thrust bearing is positioned at a first end of the shaft and the impeller is coupled to a second end of the shaft opposite the first end.

18. a sensor disposed within the compressor, the sensor communicatively coupled to the controller, the sensor configured to transmit the data indicative of the detected distance to the controller, the controller further comprising: Comparing the detected distance with a predetermined value; 17. The HVAC&R system of claim 16, configured to control operation of the thrust bearing based on a comparison of the detected distance to the predetermined value.

19. 20. The HVAC&R system of claim 18, wherein the predetermined value corresponds to an alignment of an outlet of the impeller with a diffuser passage in the housing downstream of the outlet with respect to a flow of working fluid through the compressor.

20. 17. The HVAC&R system of claim 16, wherein the shroud comprises a planar surface extending around the impeller, and the HVAC&R system comprises a sensor disposed within the compressor, the sensor communicatively coupled to the controller, the sensor configured to detect the planar surface and measure the detected distance.

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