Compressor System for Heating, Ventilation, Air Conditioning, And/Or Refrigeration System

This application claims priority from and the benefit of U.S. Provisional Application Ser. No. 63/353,343, entitled “COMPRESSOR SYSTEM FOR HEATING, VENTILATION, AIR CONDITIONING, AND/OR REFRIGERATION SYSTEM”, filed Jun. 17, 2022, which is hereby incorporated by reference.

This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which 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. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.

Chiller systems, or vapor compression systems, utilize a working fluid (e.g., a refrigerant) that changes phases between vapor, liquid, and combinations thereof in response to exposure to different temperatures and pressures within components of the chiller system. The chiller system may place the working fluid in a heat exchange relationship with a cooling fluid (e.g., water) and may deliver the cooling fluid to conditioning equipment and/or a conditioned environment serviced by the chiller system. In some embodiments, the chiller system may include an economizer configured to improve an efficiency of the chiller system. For example, a first heat exchanger (e.g., a condenser) may cool the working fluid and direct the cooled working fluid to the economizer, which may reduce a pressure of the working fluid to further cool the working fluid and separate the working fluid into liquid phase working fluid and vapor phase working fluid. The economizer may direct the liquid phase working fluid to a second heat exchanger (e.g., an evaporator) configured to place the working fluid in the heat exchange relationship with the cooling fluid. The economizer may direct the vapor phase working fluid to a compressor for pressurization. Unfortunately, existing chiller systems that include economizers may operate inefficiently.

A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below.

In one embodiment, a heating, ventilation, air conditioning, and/or refrigeration (HVAC&R) system includes an economizer system configured to reduce a pressure of a first portion of a refrigerant, an auxiliary compressor system configured to receive the first portion of the refrigerant from the economizer system, where the auxiliary compressor system comprises a first auxiliary compressor and a second auxiliary compressor, and a primary compressor. The HVAC&R system also includes a condenser configured to receive the first portion of the refrigerant from the auxiliary compressor system and a second portion of the refrigerant from the primary compressor.

In another embodiment, a heating, ventilation, air conditioning, and/or refrigeration (HVAC&R) system, comprising an economizer system configured to reduce a pressure of a refrigerant to provide a first vapor refrigerant flow and a second vapor refrigerant flow. The HVAC&R system also includes an auxiliary compressor system that has a first auxiliary compressor configured to receive the first vapor refrigerant flow from the economizer system and pressurize the first vapor refrigerant flow to provide a first pressurized vapor refrigerant flow and a second auxiliary compressor configured to receive the second vapor refrigerant flow from the economizer system and pressurize the second vapor refrigerant flow to provide a second pressurized vapor refrigerant flow. The auxiliary compressor system is configured to discharge a combined vapor refrigerant flow comprising the first pressurized vapor refrigerant flow and the second pressurized vapor refrigerant flow toward a condenser of the HVAC&R system.

In still another embodiment, a compression system of a heating, ventilation, air conditioning, and/or refrigeration (HVAC&R) system includes an auxiliary compressor system configured to receive a first portion of a refrigerant from an economizer system of the HVAC&R system. The auxiliary compression system includes a first auxiliary compressor and a second auxiliary compressor. The compression system also includes a primary compressor configured to receive a second portion of the refrigerant from an evaporator of the HVAC&R system.

One or more specific embodiments will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.

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. Additionally, 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.

Embodiments of the present disclosure relate to a heating, ventilation, air conditioning, and/or refrigeration (HVAC&R) system having a vapor compression system (e.g., a vapor compression circuit). The vapor compression system may include a compressor (e.g., a primary compressor) configured to pressurize a working fluid within the vapor compression system and direct the working fluid to a condenser, which may cool and condense the working fluid. The condensed working fluid may be directed toward an expansion device, which may reduce a pressure of the working fluid, further cooling the working fluid. From the expansion device, the cooled working fluid may be directed to an evaporator, where the working fluid may be placed in a heat exchange relationship with a cooling fluid to cool the cooling fluid. The compressor may then receive the working fluid from the evaporator for pressurization to restart the vapor compression cycle.

In some embodiments, the vapor compression system may include an economizer system configured to receive the working fluid from the condenser. The economizer system may be configured to reduce a pressure of the working fluid to further cool the working fluid and separate the working fluid into liquid working fluid and vapor working fluid. The economizer system may direct the liquid working fluid to the evaporator to enable the evaporator to place the liquid working fluid in a heat exchange relationship with the cooling fluid. The vapor working fluid may be directed from the economizer system toward the condenser. However, the vapor working fluid directed from the economizer system may not readily flow toward the condenser in some circumstances. For example, the working fluid pressurized by the compressor may also be directed toward the condenser to mix with the working fluid directed from the economizer system, but the working fluid from the compressor and the working fluid from the economizer system may be at different pressures. Such a pressure differential may disrupt flow of the working fluid to the condenser, such as by causing back flow of working fluid toward the compressor and/or toward the economizer. Thus, the working fluid may not efficiently flow toward the condenser from the economizer. It should be noted that reference to a element (e.g., a system, component, or the like) directing a fluid (e.g., refrigerant in a vapor or liquid phase) toward another element indicates that the element pressurizes, forces, guides (e.g., via piping, valves, mechanical operation), or the like the fluid directly or indirectly to the other element.

It is now recognized that improvements are desired for HVAC&R systems having an economizer system. The present disclosure is directed to incorporating an additional, auxiliary compressor system configured to receive vapor working fluid from an economizer system, pressurize the vapor working fluid, and direct the pressurized vapor working fluid toward the condenser. The auxiliary compressor system may pressurize the vapor working fluid toward the pressure of the working fluid pressurized by the compressor (e.g., the primary compressor) to reduce a pressure differential between the respective working fluid flows directed toward the condenser, thereby facilitating efficient flow of the working fluid through the HVAC&R system. The auxiliary compressor system may include multiple auxiliary compressors that may be less costly than a single compressor that can handle the same load. Additionally or alternatively, each auxiliary compressor may occupy a smaller physical footprint than would be occupied by a single compressor to enable efficient usage of space via the HVAC&R system. As further described below, the auxiliary compressors may be configured in any suitable series flow arrangement and/or a parallel flow arrangement with respect to flow of the working fluid through the auxiliary compressor system to provide desirable pressurization of the vapor working fluid for flow toward the condenser. Thus, the auxiliary compressor system may improve operation of the HVAC&R system having the economizer without significantly increasing a manufacturing cost of and/or footprint occupied by the HVAC&R system.

Turning now to the drawings,is a perspective view of an embodiment of an environment for a heating, ventilation, air conditioning, and refrigeration (HVAC&R) systemin a buildingfor a typical commercial setting. The HVAC&R systemmay include a vapor compression system(e.g., a chiller) that supplies a chilled liquid, which may be used to cool the building. The HVAC&R systemmay also include a boilerto supply warm liquid to heat the buildingand an air distribution system which circulates air through the building. The air distribution system can also include an air return duct, an air supply duct, and/or an air handler. In some embodiments, the air handlermay include a heat exchanger that is connected to the boilerand the vapor compression systemby conduits. The heat exchanger in the air handlermay receive either heated liquid from the boileror chilled liquid from the vapor compression system, depending on the mode of operation of the HVAC&R system. The HVAC&R systemis shown with a separate air handler on each floor of building, but in other embodiments, the HVAC&R systemmay include air handlersand/or other components that may be shared between or among floors.

are embodiments of the vapor compression systemthat can be used in the HVAC&R system. The vapor compression systemmay circulate a refrigerant through a circuit starting with a compressor. The circuit may also include a condenser, an expansion valve(s) or device(s), and a liquid chiller or an evaporator. The vapor compression systemmay further include a control panelthat has an analog to digital (A/D) converter, a microprocessor, a non-volatile memory, and/or an interface board.

Some examples of fluids that may be used as refrigerants in the vapor compression systemare hydrofluorocarbon (HFC) based refrigerants, for example, R-410A, R-407, R-134a, R-1234ze, R1233zd, hydrofluoro olefin (HFO), “natural” refrigerants like ammonia (NH3), R-717, carbon dioxide (CO2), R-744, or hydrocarbon based refrigerants, water vapor, or any other suitable refrigerant. In some embodiments, the vapor compression systemmay be configured to efficiently utilize refrigerants having a normal boiling point of about 19 degrees Celsius (66 degrees Fahrenheit) at one atmosphere of pressure, also referred to as low pressure refrigerants, versus a medium pressure refrigerant, such as R-134a. As used herein, “normal boiling point” may refer to a boiling point temperature measured at one atmosphere of pressure.

In some embodiments, the vapor compression systemmay use one or more of a variable speed drive (VSDs), a motor, the compressor, the condenser, the expansion valve or device, and/or the evaporator. The motormay drive the compressorand may be powered by a variable speed drive (VSD). The VSDreceives alternating current (AC) power having a particular fixed line voltage and fixed line frequency from an AC power source, and provides power having a variable voltage and frequency to the motor. In other embodiments, the motormay be powered directly from an AC or direct current (DC) power source. The motormay include any type of motor that can be powered by a VSD or directly from an AC or DC power source, such as a switched reluctance motor, an induction motor, an electronically commutated permanent magnet motor, or another suitable motor.

The compressorcompresses a refrigerant vapor and delivers the vapor to the condenserthrough a discharge passage. In some embodiments, the compressormay be a centrifugal compressor. The refrigerant vapor delivered by the compressorto the condensermay transfer heat to a cooling fluid (e.g., water or air) in the condenser. The refrigerant vapor may condense to a refrigerant liquid in the condenseras a result of thermal heat transfer with the cooling fluid. The liquid refrigerant from the condensermay flow through the expansion deviceto the evaporator. In the illustrated embodiment of, the condenseris water cooled and includes a tube bundleconnected to a cooling tower, which supplies the cooling fluid to the condenser.

The liquid refrigerant delivered to the evaporatormay absorb heat from another cooling fluid, which may or may not be the same cooling fluid used in the condenser. The liquid refrigerant in the evaporatormay undergo a phase change from the liquid refrigerant to a refrigerant vapor. As shown in the illustrated embodiment of, the evaporatormay include a tube bundlehaving a supply lineS and a return lineR connected to a cooling load. The cooling fluid of the evaporator(e.g., water, ethylene glycol, calcium chloride brine, sodium chloride brine, or any other suitable fluid) enters the evaporatorvia return lineR and exits the evaporatorvia supply lineS. The evaporatormay reduce the temperature of the cooling fluid in the tube bundlevia thermal heat transfer with the refrigerant. The tube bundlein the evaporatorcan include a plurality of tubes and/or a plurality of tube bundles. In any case, the vapor refrigerant exits the evaporatorand returns to the compressorby a suction line to complete the cycle.

is a schematic of the vapor compression systemwith an intermediate circuitincorporated between condenserand the expansion device. The intermediate circuitmay have an inlet linethat is directly fluidly connected to the condenser. In other embodiments, the inlet linemay be indirectly fluidly coupled to the condenser. As shown in the illustrated embodiment of, the inlet lineincludes a first expansion devicepositioned upstream of an intermediate vessel. In some embodiments, the intermediate vesselmay be a flash tank (e.g., a flash intercooler, an economizer). In other embodiments, the intermediate vesselmay be configured as a heat exchanger or a “surface economizer.” In the illustrated embodiment of, the intermediate vesselis used as a flash tank, and the first expansion deviceis configured to lower the pressure of (e.g., expand) the liquid refrigerant received from the condenser. During the expansion process, a portion of the liquid may vaporize, and thus, the intermediate vesselmay be used to separate the vapor from the liquid received from the first expansion device.

Additionally, the intermediate vesselmay provide for further expansion of the liquid refrigerant because of a pressure drop experienced by the liquid refrigerant when entering the intermediate vessel(e.g., due to a rapid increase in volume experienced when entering the intermediate vessel). The vapor in the intermediate vesselmay be drawn by the compressorthrough a suction lineof the compressor. In other embodiments, the vapor in the intermediate vessel may be drawn to an intermediate stage of the compressor(e.g., not the suction stage). The liquid that collects in the intermediate vesselmay be at a lower enthalpy than the liquid refrigerant exiting the condenserbecause of the expansion in the expansion deviceand/or the intermediate vessel. The liquid from intermediate vesselmay then flow in linethrough a second expansion deviceto the evaporator.

It should be appreciated that any of the features described herein may be incorporated with the vapor compression systemor any other suitable HVAC&R systems. For example, the present techniques may be incorporated with any HVAC&R system having an economizer, such as the intermediate vessel, and a compressor, such as the compressor. The discussion below describes the present techniques incorporated with embodiments of the compressorconfigured as a single stage compressor. However, it should be noted that the systems and methods described herein may be incorporated with other embodiments of the compressorand HVAC&R system.

The present disclosure is directed to a vapor compression system that includes an economizer system (e.g., an intermediate vessel) configured to receive refrigerant from a condenser and to separate the refrigerant into liquid refrigerant and vapor refrigerant. The economizer system may direct the liquid refrigerant to an evaporator of the vapor compression system to enable the evaporator to place the liquid refrigerant in a heat exchange relationship with a cooling fluid to cool the cooling fluid. The vapor compression system may include an auxiliary compressor system that has multiple auxiliary compressors configured to receive and pressurize the vapor refrigerant directed from the economizer system. The auxiliary compressor system may direct the pressurized vapor refrigerant to a condenser, which may cool the vapor refrigerant. For example, the auxiliary compressors of the auxiliary compressor system may be in a series flow arrangement and/or a parallel flow arrangement suitable for increasing the pressure of the vapor refrigerant to a desirable level for discharge toward the condenser. Additionally, the auxiliary compressors may be less costly and/or may occupy a smaller physical footprint as compared to conventional compressor embodiments, such as that of a primary compressor of the vapor compression system. Thus, the auxiliary compressor system may provide desirable operations without significantly increasing a manufacturing cost of and/or a physical footprint occupied by the HVAC&R system.

With the foregoing in mind,is a schematic of an embodiment of a vapor compression systemthat includes a primary compressor(e.g., the compressor, a single stage compressor, a multistage compressor), the condenser, the evaporator, and an economizer system(e.g., the intermediate vessel, an intercooler). The primary compressormay include any suitable number of compressor stages, such as one compressor stage or two or more compressor stages. The vapor compression systemalso includes an auxiliary compressor system(e.g., a secondary compressor system, a parallel compressor system) fluidly coupled to the economizer system. The auxiliary compressor systemmay draw vapor refrigerant from the economizer system, compress the vapor refrigerant, and discharge the compressed vapor refrigerant toward the condenser. As an example, the auxiliary compressor system, instead of the primary compressor, may receive the vapor refrigerant from economizer system. The auxiliary compressor systemmay pressurize the received vapor refrigerant and direct the pressurized vapor refrigerant toward the condenserand bypass the primary compressor.

In some embodiments, the auxiliary compressor systemmay increase the pressure of the vapor refrigerant toward that of the vapor refrigerant pressurized by the primary compressor. For example, a first pressure of the vapor refrigerant directed from the primary compressorinto the condenser(e.g., via a first condenser inlet) may be similar or substantially the same as a second pressure of the vapor refrigerant directed from the auxiliary compressor systeminto the condenser(e.g., via a second condenser inlet). Pressurization of the refrigerant flows to approximately the same pressure may reduce disruptions to refrigerant flow toward the condenser(e.g., by blocking back flow of refrigerant through the first condenser inletand/or through the second condenser inlet) that may otherwise occur because of a pressure differential between the respective refrigerant flows from the primary compressorand from the economizer system. As such, the refrigerant may more readily flow through the condenser. For example, a desirable flow (e.g., a target flow rate) of refrigerant through the vapor compression systemand/or a desirable cooling of the refrigerant provided via the condensermay be achieved. In certain embodiments or operational configurations, it should be noted that the primary compressorprovides substantially all of the compression head from an outletof the evaporatorto an outletof the primary compressor(and the inletto the condenserfrom the primary compressor). The auxiliary compressor systemprovides a pressure boost to the refrigerant entering the condenserfrom the economizer system.

An amount of pressurization provided by the auxiliary compressor systemmay be less than that provided by the primary compressor. By way of example, the pressure of the vapor refrigerant directed from the economizer systemto the auxiliary compressor systemmay be greater than the pressure of the refrigerant directed from the evaporatorto the primary compressor. As such, a first pressure differential between the pressure of the refrigerant received by the auxiliary compressor systemand a corresponding target pressure for pressurization by the auxiliary compressor systemmay be less than a second pressure differential between the pressure of the refrigerant received by the primary compressorand a corresponding target pressure for pressurization by the primary compressor. For this reason, a selected embodiment of a compressor utilized by the auxiliary compressor systemmay be different than the embodiment of the primary compressorto provide the desirable pressurization of the refrigerant flow from the economizer system. For instance, a design specification and/or operation of the auxiliary compressor systemmay be different than that of the primary compressor. Indeed, as further described herein, the auxiliary compressor systemmay include auxiliary compressors that are associated with a reduced cost, a reduced size, an increased configurability, and so forth. Thus, the auxiliary compressor systemmay provide desirable operation, reduced cost of manufacture, improved ease of installation, and so forth associated with the vapor compression system.

is a schematic of an embodiment of the vapor compression systemthat includes the economizer systemand the auxiliary compressor system. The economizer systemmay include a plurality of economizers (e.g., economizer stages) that are each configured to reduce a pressure of a refrigerant flow. For example, a first economizer(e.g., a first economizer stage) may receive the refrigerant from the condenser, reduce a pressure of the refrigerant to vaporize a portion of the refrigerant, and separate the refrigerant into liquid refrigerant and vapor refrigerant. The first economizermay direct the vapor refrigerant as a first vapor refrigerant flowtoward the auxiliary compressor system, and the first economizermay direct the liquid refrigerant as a first liquid refrigerant flowto a second economizer. The second economizermay reduce the pressure of the first liquid refrigerant flowreceived from the first economizerto vaporize a portion of the refrigerant and separate the refrigerant into liquid refrigerant and vapor refrigerant. The second economizermay direct the vapor refrigerant as a second vapor refrigerant flowtoward the auxiliary compressor system, and the second economizermay direct the liquid refrigerant as a second liquid refrigerant flowto a third economizer. The third economizermay further reduce a pressure of the second liquid refrigerant flowreceived from the second economizerto vaporize a portion of the refrigerant and separate the refrigerant into liquid refrigerant and vapor refrigerant. The third economizermay direct the vapor refrigerant as a third vapor refrigerant flowtoward the auxiliary compressor system, and the third economizermay direct the liquid refrigerant as a third liquid refrigerant flowto the evaporator. By further reducing the pressure of the refrigerant, the second economizerand/or the third economizermay increase cooling of the refrigerant prior to discharge toward the evaporator, thereby increasing an amount of cooling provided by the refrigerant flow in evaporatorto the cooling fluid and increasing efficient operation of the vapor compression systemto condition the cooling fluid.

In some embodiments, each economizer,,may be separate chambers, compartments, volumes, or spaces of a common or the same economizer enclosure, housing, or shell. That is, the economizer systemmay include a single economizer enclosurethat may enclose multiple economizers,,configured to reduce the pressure of the refrigerant (e.g., via stages). For instance, each economizer,,may be separated from one another within the economizer enclosurevia a partition, a divider, a wall, a plate, and the like. In additional or alternative embodiments, each economizer,,may have a respective enclosure, and the economizers,,may therefore be separate components of one another. Further, each of the economizers,,may include or be associated with one or more valves (e.g., expansion valves) to facilitate pressure drop relative to the respective economizer.

The auxiliary compressor systemmay receive each of the vapor refrigerant flows,,and pressurize the vapor refrigerant flows,,for discharge toward the condenser(e.g., via the second condenser inlet). For example, the auxiliary compressor systemmay increase a respective pressure of each vapor refrigerant flow,,toward the pressure of a primary refrigerant flowdirected from the primary compressorto reduce a pressure differential between the primary refrigerant flowdirected from the primary compressorto the condenserand the pressurized vapor refrigerant flows directed from the auxiliary compressor systemto the condenser. Thus, the auxiliary compressor systemmay facilitate flow of refrigerant to and/or through the condenser. Because the auxiliary compressor systemreceives input from each of the economizers,,, the auxiliary compressor systemoperates to increase differently pressurized flows (the vapor refrigerant flows,,) toward the pressure of the primary refrigerant flow.

As an example, the auxiliary compressor systemmay include a plurality of auxiliary compressors that are in a parallel flow arrangement. That is, each auxiliary compressor may receive a respective one of the vapor refrigerant flows,,from the economizer system. For instance, a first auxiliary compressormay receive the first vapor refrigerant flowfrom the first economizer, a second auxiliary compressormay receive the second vapor refrigerant flowfrom the second economizer, and a third auxiliary compressormay receive the third vapor refrigerant flowfrom the third economizer. The auxiliary compressors,,may pressurize the vapor refrigerant flows,,, respectively, for discharge toward the condenser. That is, the first auxiliary compressormay pressurize the first vapor refrigerant flowto provide a first pressurized vapor refrigerant flowfor discharge toward the condenser, the second auxiliary compressormay pressurize the second vapor refrigerant flowto provide a second pressurized vapor refrigerant flowfor discharge toward the condenser, and the third auxiliary compressormay pressurize the third vapor refrigerant flowto provide a third pressurized vapor refrigerant flowfor discharge toward the condenser. The pressurized vapor refrigerant flows,,may combine to provide a combined pressurized vapor refrigerant flowthat may be received by the condenser.

As noted above, in some embodiments, the respective amounts of pressurization provided by the auxiliary compressorsmay be different from one another. For example, each auxiliary compressor,,may pressurize the respective vapor refrigerant flows,,to approximately the same target pressure (e.g., substantially equal to the pressure of the primary refrigerant flow). However, the respective pressures of the vapor refrigerant flows,,received by the auxiliary compressors,,may initially have different pressures. For instance, because the third economizerprovides additional pressure reduction of the second liquid refrigerant flowfrom the second economizer, the pressure of the third vapor refrigerant flowmay be less than the pressure of the second vapor refrigerant flow. Thus, a pressure differential between the pressure of the third vapor refrigerant flowand the target pressure may be greater than a pressure differential between the pressure of the second vapor refrigerant flowand the target pressure. Similarly, because the second economizerprovides additional pressure reduction of the first liquid refrigerant flowfrom the first economizer, the pressure of the second vapor refrigerant flowmay be less than the pressure of the first vapor refrigerant flow. As such, the pressure differential between the pressure of the second vapor refrigerant flowand the target pressure may be greater than a pressure differential between the pressure of the first vapor refrigerant flowand the target pressure. For this reason, an amount of pressurization provided by the third auxiliary compressorfor the third vapor refrigerant flowmay be greater than an amount of pressurization provided by the second auxiliary compressorfor the second vapor refrigerant flow, and the amount of pressurization provided by the second auxiliary compressorfor the second vapor refrigerant flowmay be greater than an amount of pressurization provided by the first auxiliary compressorfor the first vapor refrigerant flow.

Additionally, an amount of the vapor refrigerant flows,,provided by the economizer systemmay be different from one another. For example, the mass flow of the vapor refrigerant flows,,may be based on the pressure within the condenserand/or within each of the economizers,,, and the volume flow of the vapor refrigerant flows,,may be based on the vapor density of the vapor density at the respective pressures within the economizers,,. Indeed, the amount of the first vapor refrigerant flowprovided by the first economizermay be greater or smaller than the amount of the second vapor refrigerant flowprovided by the second economizer, and the amount of the second vapor refrigerantprovided by the second economizermay be greater or smaller than the amount of the third vapor refrigerant flowprovided by the third economizer. In additional or alternative embodiments, the amount of vapor refrigerant flows,,provided by the economizer systemmay be substantially similar to one another.

Embodiments or specifications of the auxiliary compressors,,may be selected based on the respective amounts of pressurization to be provided by the auxiliary compressors,,and/or the respective amounts of the vapor refrigerant flows,,received by the auxiliary compressors,,. Thus, each auxiliary compressor,,may have a different embodiment (e.g., a different size, a different type). As an example, the first auxiliary compressormay be relatively larger or smaller than the second auxiliary compressorand/or the third auxiliary compressorto enable receipt and pressurization of the relatively larger or smaller amount, respectively, of the first vapor refrigerant flow, and/or the third auxiliary compressormay be relatively larger or smaller than the first auxiliary compressorand/or the second auxiliary compressorto enable receipt and pressurization of the relatively larger or smaller amount, respectively, of the third vapor refrigerant flow. In additional or alternative embodiments, such as embodiments in which the amount of vapor refrigerant flows,,are similar to one another, the auxiliary compressors,,may be of the same or similar embodiments.

Each auxiliary compressor,,may, for instance, include an oil-free compressor to avoid increasing a cost and/or complexity associated with management of oil and/or lubricant circulated through the vapor compression system(e.g., for cooling of the auxiliary compressors,,). Additionally or alternatively, the auxiliary compressors,,may include a scroll compressor, a centrifugal compressor, a reciprocating compressor, or any other suitable compressor type. In any case, each auxiliary compressor,,may be less costly and/or may occupy a smaller physical footprint as compared to the primary compressor.

Additionally, the vapor compression systemmay include a conduit systemconfigured to control flow of the vapor refrigerant flows,,to the auxiliary compressor system. As an example, the conduit systemmay be operated to enable a desirable or suitable flow (e.g., a target flow rate, a target flow velocity) of the vapor refrigerant flows,,to the auxiliary compressors,,. For instance, a first valveof the conduit systemmay control a flow rate of the first vapor refrigerant flowfrom the first economizerto the first auxiliary compressor, a second valveof the conduit systemmay control a flow rate of the second vapor refrigerant flowfrom the second economizerto the second auxiliary compressor, and a third valveof the conduit systemmay control a flow rate of the third vapor refrigerant flowfrom the third economizerto the third auxiliary compressor. The opening of the valves,,may be adjusted to direct the vapor refrigerant flows,,in a suitable manner to the auxiliary compressors,,(e.g., at flows based on design specifications of the auxiliary compressors,,), respectively, to enable efficient and/or desirable operation of the auxiliary compressors,,.

The vapor compression systemmay also include a control system(e.g., the control panelconfigured to operate the primary compressor, a control system separate from the control panel), which may be an automation controller and/or an electronic controller. The control systemmay be configured to control operation of various components of the vapor compression system, such as the economizer system, the auxiliary compressor system, and/or the conduit system. For example, the control systemmay include a memoryand processing circuitry. The memorymay include volatile memory, such as random-access memory (RAM), and/or non-volatile memory, such as read-only memory (ROM), optical drives, hard disc drives, solid-state drives, or any other non-transitory computer-readable medium storing instructions that, when executed, control operation of the vapor compression system. The processing circuitrymay be configured to execute such instructions stored in the memory. As an example, the processing circuitrymay 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.

As an example, the control systemmay be configured to operate each of the economizers,,to adjust the respective pressure reductions provided by the economizers,,. As another example, the control systemmay be configured to operate each of the auxiliary compressors,,, such as by adjusting a stage, a speed, a frequency, and/or any other regulation system (e.g., mechanical system) to provide desirable pressurization of the respective vapor refrigerant flows,,, such as to the target pressure. As a further example, the control systemmay be configured to operate each of the valves,,, such as by adjusting the respective openings of the valves,,, to adjust the flow rates of the vapor refrigerant flows,,to the respective auxiliary compressors,,. Thus, the control systemmay adjust operation of various components of the vapor compression system.

Although the economizer systemof the illustrated vapor compression systemincludes three economizers,,, the auxiliary compressor systemof the illustrated vapor compression systemincludes three auxiliary compressors,,, and the conduit systemof the illustrated vapor compression systemincludes three valves,,, in additional or alternative embodiments, the economizer systemmay include any suitable number of economizers,,, the auxiliary compressor systemmay include any suitable number of auxiliary compressors,,, and/or the conduit systemmay include any suitable number of valves,,. The quantity of economizers,,, the quantity of auxiliary compressors,,, and/or the quantity of valves,,may correspond to or be equal to one another in some embodiments. For example, the vapor compression systemmay include two economizers,,, two auxiliary compressors,,, and two valves,,, the vapor compression systemmay include four economizers,,, four auxiliary compressors,,, and four valves,,, and so forth.

is a schematic of an embodiment of the vapor compression systemthat includes the economizer systemand the auxiliary compressor system. In the illustrated embodiment, the economizer systemincludes the first economizerconfigured to direct the first vapor refrigerant flowto the auxiliary compressor systemand the first liquid refrigerant flowto the second economizer, as well as the second economizerconfigured to direct the second vapor refrigerant flowto the auxiliary compressor systemand the second liquid refrigerant flowto the evaporator. The auxiliary compressor systemincludes the first auxiliary compressorconfigured to receive the first vapor refrigerant flowfrom the first economizer, as well as the second auxiliary compressor configured to receive the second vapor refrigerant flowfrom the second economizer. The conduit systemof the vapor compression systemincludes the first valveconfigured to control flow of the first vapor refrigerant flowto the first auxiliary compressor, as well as the second valveconfigured to control flow of the second vapor refrigerant flowto the second auxiliary compressor.

The auxiliary compressors,may be in a series flow arrangement. For example, the second auxiliary compressormay pressurize the second vapor refrigerant flowreceived from the second economizerto provide the second pressurized vapor refrigerant flowas discharge toward the first auxiliary compressor. The second pressurized vapor refrigerant flowmay combine with the first vapor refrigerant flowdirected from the first economizerfor intake by the first auxiliary compressor. For this reason, the second auxiliary compressormay increase the pressure of the second vapor refrigerant flowtoward the pressure of the first vapor refrigerant flowdirected from the first economizerto enable the second pressurized vapor refrigerant flowfrom the second auxiliary compressorand the first vapor refrigerant flowfrom the first economizerto flow more readily to the first auxiliary compressor. For instance, the second pressurized vapor refrigerant flowand the first vapor refrigerant flowthat are at substantially the same pressure may flow toward the first auxiliary compressorinstead of, for example, back flowing toward the first economizerand/or toward the second auxiliary compressor.

The first auxiliary compressormay pressurize the second pressurized vapor refrigerant flowand the first vapor refrigerant flowto provide a combined pressurized vapor refrigerant flowfor discharge toward the condenser. Thus, the second vapor refrigerant flowmay be pressurized by the second auxiliary compressorand further pressurized by the first auxiliary compressor. In this manner, the auxiliary compressor systemmay provide multi-stage compression of the second vapor refrigerant flow(e.g., the second auxiliary compressormay be a first compressor stage providing initial pressurization, and the first auxiliary compressormay be a second compressor stage providing further pressurization). The first auxiliary compressormay increase the pressure of the second pressurized vapor refrigerant flowand the first vapor refrigerant flowtoward that of the primary refrigerant flowto facilitate flow of the combined pressurized vapor refrigerant flowfrom the auxiliary compressor systemand the primary refrigerant flowfrom the primary compressorto and/or through the condenser.

The first auxiliary compressorand the second auxiliary compressormay be of different embodiments. For example, the embodiment of the first auxiliary compressormay be selected to enable receipt and pressurization of both the first vapor refrigerant flowand the second pressurized vapor refrigerant flow. Thus, the embodiment of the first auxiliary compressormay enable increased refrigerant capacity or flow therethrough as compared to the embodiment of the second auxiliary compressor, which may pressurize the second vapor refrigerant flowand not the first vapor refrigerant flow.

In some embodiments, the auxiliary compressor systemmay include more than two auxiliary compressors,in series with one another. For example, in embodiments in which the economizer systemincludes the third economizerconfigured to receive the second liquid refrigerant flowfrom the second economizer, the auxiliary compressor systemmay include the third auxiliary compressorconfigured to receive and pressurize the third vapor refrigerant flowfrom the third economizerto provide the third pressurized vapor refrigerant flow. The third pressurized vapor refrigerant flowmay be discharged toward the second auxiliary compressorand then toward the first auxiliary compressorfor further staged pressurization. Thus, in the series flow arrangement, certain vapor refrigerant flows from the economizer systemmay be pressurized by multiple auxiliary compressors.

is a schematic of an embodiment of the vapor compression systemthat includes the economizer systemand the auxiliary compressor system. In the illustrated embodiment, the economizer systemincludes the first economizer, which may direct the first liquid refrigerant flowto the evaporator. The first economizermay also direct a first vapor refrigerant flowand a second vapor refrigerant flowtoward the auxiliary compressor system, which may include the first auxiliary compressorand the second auxiliary compressor. For example, the first economizermay produce vapor refrigerant by reducing the pressure of the refrigerant received from the condenser, and the first economizermay apportion the produced vapor refrigerant to direct the first vapor refrigerant flowtoward the first auxiliary compressorand the second vapor refrigerant flowtoward the second auxiliary compressor. For instance, the conduit systemmay include the first valveconfigured to control flow of the first vapor refrigerant flowto the first auxiliary compressor, as well as the second valveconfigured to control flow of the second vapor refrigerant flowto the second auxiliary compressor. The control systemmay adjust the openings of the valves,to control flow of the vapor refrigerant flows,to the auxiliary compressors,.

The auxiliary compressors,may be in a parallel flow arrangement. That is, the auxiliary compressors,may pressurize the respective vapor refrigerant flows,for discharge toward the condenser. As an example, the first auxiliary compressormay pressurize the first vapor refrigerant flowto provide a first pressurized vapor refrigerant flowand discharge the first pressurized vapor refrigerant flowtoward the condenser. The second auxiliary compressormay pressurize the second vapor refrigerant flowto provide a second pressurized vapor refrigerant flowand discharge the second pressurized vapor refrigerant flowtoward the condenser. The first pressurized vapor refrigerant flowand the second pressurized vapor refrigerant flowmay combine as a combined pressurized vapor refrigerant flowfor intake by the condenser. Thus, the first pressurized vapor refrigerant flowmay bypass flow through the second auxiliary compressor, and/or the second pressurized vapor refrigerant flowmay bypass flow through the first auxiliary compressor. The auxiliary compressors,may increase the pressure of the respective vapor refrigerant flows,toward the pressure of the primary refrigerant flowdischarged by the primary compressorto facilitate directing the primary refrigerant flow, the first pressurized vapor refrigerant flow, and the second pressurized vapor refrigerant flowto and/or through the condenser.

In additional or alternative embodiments, the vapor refrigerant provided by the first economizermay be apportioned to more than two auxiliary compressors,. For example, a third vapor refrigerant flow may be directed from the first economizertoward a third auxiliary compressor for pressurization and discharge toward the condenser.

is a schematic of an embodiment of the vapor compression systemthat includes the economizer systemand the auxiliary compressor system. In the illustrated embodiment, the economizer systemincludes the first economizerand the second economizer. The first economizermay be configured to direct the first vapor refrigerant flowto the auxiliary compressor systemand the first liquid refrigerant flowto the second economizer. The second economizermay be configured to direct the second vapor refrigerant flowto the auxiliary compressor systemand the second liquid refrigerant flowto the evaporator. The auxiliary compressor systemincludes the first auxiliary compressor, the second auxiliary compressor, and the third auxiliary compressor. The first auxiliary compressormay be configured to receive the first vapor refrigerant flowfrom the first economizer, and the second auxiliary compressormay be configured to receive the second vapor refrigerant flowfrom the second economizer. The conduit systemincludes the first valveconfigured to control flow of the first vapor refrigerant flowto the first auxiliary compressor, as well as the second valveconfigured to control flow of the second vapor refrigerant flowto the second auxiliary compressor.

The first auxiliary compressormay pressurize the first vapor refrigerant flowto provide the first pressurized vapor refrigerant flowfor discharge toward the condenser. For example, the first vapor refrigerant flowmay bypass flow through the second auxiliary compressorand the third auxiliary compressor. The second auxiliary compressormay pressurize the second vapor refrigerant flowto provide the second pressurized vapor refrigerant flow, and the second auxiliary compressormay discharge the second pressurized vapor refrigerant flowtoward the third auxiliary compressor. The third auxiliary compressormay further pressurize the second pressurized vapor refrigerant flowto provide a third pressurized vapor refrigerant flowfor discharge toward the condenser. Thus, the third pressurized vapor refrigerant flowmay bypass flow through the first auxiliary compressor. The first pressurized vapor refrigerant flowdischarged by the first auxiliary compressorand the third pressurized vapor refrigerant flowdischarged by the third auxiliary compressormay combine to form a combined pressurized vapor refrigerant flowfor intake by the condenser. The first auxiliary compressormay increase the pressure of the first vapor refrigerant flowand the third auxiliary compressormay increase the pressure of the second vapor refrigerant flowto approximately the same pressure, such as a pressure substantially equal to the pressure of the primary refrigerant flow.

In this manner, the second auxiliary compressorand the third auxiliary compressormay be in a series flow arrangement with one another, and the first auxiliary compressormay be in a parallel flow arrangement with respect to the second auxiliary compressorand the third auxiliary compressor. Indeed, the second auxiliary compressorand the third auxiliary compressormay operate as a multi-stage compressor for the second vapor refrigerant flowin which the second vapor refrigerant flowmay be pressurized by the second auxiliary compressorand further pressurized by the third auxiliary compressorto achieve a desirable pressure of the third pressurized vapor refrigerant flowfor discharge toward the condenser.

Although the illustrated auxiliary compressor systemincludes the second auxiliary compressorand the third auxiliary compressorin a series flow arrangement, in additional or alternative embodiments, the first auxiliary compressormay be in a series flow arrangement with an additional auxiliary compressor (e.g., a fourth auxiliary compressor). In further embodiments, more than two auxiliary compressors (e.g., the second auxiliary compressor, the third auxiliary compressor, and a fourth auxiliary compressor) may be in a series flow arrangement with one another, while also in a parallel series flow arrangement with another auxiliary compressor (e.g., the first auxiliary compressor).

is a schematic of an embodiment of the vapor compression systemthat includes the economizer systemand the auxiliary compressor system. In the illustrated embodiment, the economizer systemincludes the first economizerconfigured to direct the first vapor refrigerant flowto the auxiliary compressor systemand the first liquid refrigerant flowto the second economizer, as well as the second economizerconfigured to direct the second vapor refrigerant flowto the auxiliary compressor systemand the second liquid refrigerant flowto the evaporator. The auxiliary compressor systemmay include the first auxiliary compressor, the second auxiliary compressor, and the third auxiliary compressor.