WO2025128178A1

WO2025128178A1 - Intercooled combined heat and power plant

Info

Publication number: WO2025128178A1
Application number: PCT/US2024/049174
Authority: WO
Inventors: Joseph T. Williams
Original assignee: Siemens Energy Inc
Current assignee: Siemens Energy Inc
Priority date: 2023-12-12
Filing date: 2024-09-30
Publication date: 2025-06-19
Anticipated expiration: 2026-06-12

Abstract

A power conversion system includes a Brayton cycle that uses a working fluid to generate electrical power. The Brayton cycle includes an intercooler and a secondary heat exchanger. A heat source is operable outside of the Brayton cycle to generate heat, a flow of hot fluid is operable to transfer heat from the heat source to the Brayton cycle, and a process fluid supply is operable to deliver a process fluid. A distributor is positioned to receive the process fluid and operable to deliver a first portion of the process fluid to the secondary heat exchanger to produce a first flow of hot process fluid having a first temperature, and to deliver a second portion of the process fluid to the intercooler to produce a second flow of hot process fluid having a second temperature. A controller is operable to adjust the distributor to vary the first portion and the second portion to maintain the first temperature at a first desired vale and to maintain the second temperature at a second desired value.

Description

Docket No. 2023PF12321 INTERCOOLED COMBINED HEAT AND POWER PLANT BACKGROUND [0001] Power generation, and in particular thermal power generation is an energy conversion process in which energy is generated in the form of heat which is in turn used to drive a thermal cycle such as a Brayton cycle. While combustion processes are often used in Brayton cycles, other heat sources can be used to replace the combustor. In addition, waste heat can be used to heat a process fluid as part of the system. BRIEF SUMMARY [0002] In one construction, a power conversion system includes a heat source operable to provide a flow of hot fluid, a generator operable to produce electrical power in response to rotation, and a low-pressure compressor operable to compress a working fluid to a first pressure. A high-pressure compressor is operable to compress the working fluid from the first pressure to a second pressure, an intercooler is arranged to receive the working fluid from the low-pressure compressor and discharging the working fluid to the high-pressure compressor, and a primary heat exchanger is arranged to receive the flow of hot fluid and the working fluid and to discharge a hot working fluid. An expander is operable to rotate the generator in response to the passage of the hot working fluid therethrough, a secondary heat exchanger is coupled to the expander to receive the flow of hot working fluid therefrom, and a distributor is movable between a first position in which a process fluid is directed to the secondary heat exchanger and discharged therefrom at a first temperature, and a second position in which the process fluid is directed to the intercooler and discharged therefrom at a second temperature. [0003] In another construction, a power conversion system includes a Brayton cycle that uses a working fluid to generate electrical power. The Brayton cycle includes an intercooler and a secondary heat exchanger. A heat source is operable outside of the Brayton cycle to generate Docket No. 2023PF12321 heat, a flow of hot fluid is operable to transfer heat from the heat source to the Brayton cycle, and a process fluid supply is operable to deliver a process fluid. A distributor is positioned to receive the process fluid and operable to deliver a first portion of the process fluid to the secondary heat exchanger to produce a first flow of hot process fluid having a first temperature, and to deliver a second portion of the process fluid to the intercooler to produce a second flow of hot process fluid having a second temperature. A controller is operable to adjust the distributor to vary the first portion and the second portion to maintain the first temperature at a first desired vale and to maintain the second temperature at a second desired value. [0004] In yet another construction, a method of operating a power conversion system includes directing a working fluid through a Brayton cycle to produce electrical power, the Brayton cycle including an intercooler and a secondary heat exchanger. The method also includes operating a nuclear reactor to generate heat, directing a flow of hot fluid through the nuclear reactor and the Brayton cycle to transfer thermal energy from the nuclear reactor to the Brayton cycle, and directing a process fluid to a distributor. The method further includes operating the distributor to direct a first portion of the working fluid to the secondary heat exchanger to produce a first flow of hot process fluid having a first temperature, and to direct a second portion of the working fluid to the intercooler to produce a second flow of hot process fluid having a second temperature, and varying the operation of the distributor to maintain the first temperature at a first desired temperature and the second temperature at a second desired temperature. BRIEF DESCRIPTION OF THE DRAWINGS [0005] To easily identify the discussion of any particular element or act, the most significant digit or digits in a reference number refer to the figure number in which that element is first introduced. [0006] FIG. 1 schematically illustrates a power conversion system including two process flow loops. [0007] FIG. 2 illustrates a process for operating a power conversion system in accordance with the embodiment of FIG. 1. Docket No. 2023PF12321 DETAILED DESCRIPTION [0008] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in this description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. [0009] Various technologies that pertain to systems and methods will now be described with reference to the drawings, where like reference numerals represent like elements throughout. The drawings discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged apparatus. It is to be understood that functionality that is described as being carried out by certain system elements may be performed by multiple elements. Similarly, for instance, an element may be configured to perform functionality that is described as being carried out by multiple elements. The numerous innovative teachings of the present application will be described with reference to exemplary non-limiting embodiments. [0010] It should be understood that the words or phrases used herein should be construed broadly, unless expressly limited in some examples. For example, the terms “including,” “having,” and “comprising,” as well as derivatives thereof, mean inclusion without limitation. The singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Further, the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. The term “or” is inclusive, meaning and/or, unless the context clearly indicates otherwise. The phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like. Furthermore, while multiple embodiments or constructions may be described herein, any Docket No. 2023PF12321 features, methods, steps, components, etc. described with regard to one embodiment are equally applicable to other embodiments absent a specific statement to the contrary. [0011] Also, terms such as “first”, “second”, “third” and so forth may be used herein to refer to various elements, information, functions, or acts, but should not be considered as limiting in any way. Rather these numeral adjectives are used to distinguish different elements, information, functions or acts from each other. For example, a first element, information, function, or act could be termed a second element, information, function, or act, and, similarly, a second element, information, function, or act could be termed a first element, information, function, or act, without departing from the scope of the present disclosure. [0012] In addition, the term “adjacent to” may mean that an element is relatively near to but not in contact with a further element or that the element is in contact with the further portion unless the context clearly indicates otherwise. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise. Terms “about” or “substantially” or like terms are intended to cover variations in a value that are within normal industry manufacturing tolerances for that dimension. If no industry standard is available, a variation of twenty percent would fall within the meaning of these terms unless otherwise stated. [0013] FIG. 1 illustrates a power conversion system 100 that includes a Brayton cycle that uses an external heat source 124 in place of the more typical combustor. The heat source 124 may include any source of heat capable of heating a working fluid 142 for use in the Brayton cycle 102. Heat sources 124 may include concentrated solar, combustors, nuclear reactors, including small modular reactors (SMR), geothermal, electrical heaters, waste heat from other processes, and the like. The particular heat source 124 employed by the power conversion system 100 is not critical to the design. However, a preferred arrangement of the power conversion system 100 includes one or more SMRs that operate as the heat source 124. [0014] In the preferred arrangement, the SMR operates as the heat source 124 to produce a flow of hot fluid 140. The flow of hot fluid 140 could include water, molten salt, liquid metal, helium, or any other suitable material. [0015] The Brayton cycle 102 operates using a working fluid 142 that in the illustrated construction is air. Thus, the Brayton cycle 102 illustrated in FIG. 1 is an open cycle. Docket No. 2023PF12321 However, other arrangements could employ a different working fluid 142 and could utilize a closed cycle in which the working fluid 142 is recycled or reused rather than drawn in from the atmosphere. [0016] In the construction of FIG. 1, the working fluid 142, in the form of air enters the cycle via an air intake 104. The air intake 104 may include a filter system, inlet guide vanes (variable or fixed), other flow control members, air treatment systems, and the like as may be desired for the particular application. After passing through the air intake 104, the working fluid 142 enters a low-pressure compressor 106 where it is initially compressed to a first pressure greater than atmospheric pressure. The compression process heats the working fluid 142 which causes expansion and increases the amount of work needed to achieve the desired additional compression. To address this, the working fluid 142 is directed to an intercooler 108 where the working fluid 142 is cooled to a level that facilitates more efficient compression. [0017] After exiting the intercooler 108 the working fluid 142 flows into a high-pressure compressor 110 where it is compressed from the first pressure to a second pressure that is greater than the first pressure. The design and arrangement of the low-pressure compressor 106 and the high-pressure compressor 110 are not critical to the power conversion system 100. In some constructions, multi-stage axial flow compressors are employed for each of the low- pressure compressor 106 and the high-pressure compressor 110. However, other constructions may employ single stage fans, centrifugal compressors (single or multi-stage), or combinations thereof. [0018] After exiting the high-pressure compressor 110 the compressed working fluid 142 passes through a recuperator 112 where the working fluid 142 is further heated. After exiting the recuperator 112 the working fluid 142 enters a primary heat exchanger 114. Within the primary heat exchanger 114, heat from the flow of hot fluid 140 is transferred to the working fluid 142 to heat the working fluid 142 to achieve a desired turbine inlet temperature. As discussed, the flow of hot fluid 140 is heated by the heat source 124, which in this example is a SMR, to a desired primary heat exchanger inlet temperature which is selected to achieve the desired level of heating for the working fluid 142. As the flow of hot fluid 140 passes through the primary heat exchanger 114 it is cooled. After exiting the primary heat exchanger 114, the flow of hot fluid 140 returns to the heat source 124 and is reheated to complete a hot fluid cycle Docket No. 2023PF12321 [0019] The fully heated and compressed working fluid 142 exits the primary heat exchanger 114 and flows to an inlet of an expander 116. The expander 116 operates to convert the pressure and temperature of the working fluid 142 into rotational energy that drives a generator 118 to generate electrical power. Alternatively, the expander 116 can drive another device such as a compressor, pump or some other device. In addition, while not illustrated, the expander 116 or another expander or turbine could use a portion of the fully heated working fluid to provide rotational energy to drive the low-pressure compressor 106 and/or the high- pressure compressor 110. The expander 116 may include one or more turbines including single or multi-stage axial or centrifugal flow turbines or combinations thereof. [0020] After exiting the expander 116, the working fluid 142 still has a significant quantity of thermal energy. To improve the efficiency of the Brayton cycle 102 the working fluid 142 is directed to the recuperator 112 where it is used to preheat the working fluid 142 prior to the working fluid 142 entering the primary heat exchanger 114. The process of preheating the working fluid 142 in the recuperator 112 also serves to cool the working fluid 142 that has been discharged from the expander 116. [0021] After exiting the recuperator 112, the discharged working fluid 142 still contains useful thermal energy and is therefore directed to a secondary heat exchanger 120. As will be discussed, additional thermal energy is extracted from the working fluid 142 in the secondary heat exchanger 120 before the working fluid 142 is discharged from the Brayton cycle 102 via the air discharge 122. The air discharge 122 may be a simple discharge stack or may include air cleaning components that extract any undesirable components from the working fluid 142 before it is discharged into the atmosphere to complete an open working fluid cycle 148. In closed Brayton cycles 102, the air discharge 122 directs the working fluid 142 back to the air intake 104 thus completing a closed working fluid cycle 148. [0022] Each of the intercooler 108, recuperator 112, primary heat exchanger 114, and secondary heat exchanger 120 may include any suitable arrangement of a heat exchanger. Each heat exchanger arrangement is selected to achieve the desired level of heat transfer, at the operating conditions expected, and considering the various media employed. As such, the power conversion system 100 should not be limited to any particular arrangement or design for a heat exchanger. Docket No. 2023PF12321 [0023] Furthermore, it should be noted that the Brayton cycle 102 does not require the intercooler 108, the recuperator 112, or the secondary heat exchanger 120. Any one, or all of these heat exchanges could be omitted for any particular design. [0024] Additionally, while the low-pressure compressor 106 and the high-pressure compressor 110 are illustrated as two separate components, they may alternatively be arranged as a single compressor with an extraction at some point that leads to the intercooler 108 and a return downstream of the extraction to return the cooled working fluid 142. In arrangements that omit the intercooler 108, the low-pressure compressor 106 and the high-pressure compressor 110 may be condensed into a single compressor. The actual arrangement of the compressor is not critical to the design and operation of the power conversion system 100, but rather is selected to fit the particular application and operating conditions. [0025] With continued reference to FIG. 1, the power conversion system 100 also includes a process fluid supply 130 and a distributor 132 that operates to direct a process fluid 144 into one of two process fluid cycles 150. The process fluid supply 130 may include a tank or other collection or storage component or may simply be a collection point or a source of the process fluid 144. [0026] The process fluid 144 is directed from the process fluid supply 130 to the distributor 132 that operates to direct a first portion or first percentage of the process fluid 144 to one of the two process fluid cycles 150 and a second portion or second percentage of the process fluid 144 to the other of the two process fluid cycles 150. In the illustrated arrangement, the distributor 132 includes a multi-position valve 138 that is movable between a first position in which one hundred percent of the process fluid 144 is directed to a first of the two process fluid cycles 150 which includes the secondary heat exchanger 120 and a second position in which one hundred percent of the process fluid 144 is directed to a second of the two process fluid cycles 150 which includes the intercooler 108. To be clear, the multi-position valve 138 is movable to any position between the first position and the second position to distribute the process fluid 144 to each of the process fluid cycles 150 as desired. [0027] With the multi-position valve 138 in any but the second position, at least a portion of the process fluid 144 flows through the distributor 132 and enters the secondary heat exchanger 120. The working fluid 142 passing through the secondary heat exchanger 120 operates to heat Docket No. 2023PF12321 the process fluid 144 within the secondary heat exchanger 120 before it is discharged at a first temperature 134. The process fluid 144 then flows to a process fluid consumer 126 where that process fluid 144 is used for some purpose. After the process fluid 144 is used, it is returned to the process fluid supply 130 or discharged from the system. [0028] With the multi-position valve 138 in any but the first position, at least a portion of the process fluid 144 flows through the distributor 132 and enters the intercooler 108. The working fluid 142 passing through the intercooler 108 operates to heat the process fluid 144 within the intercooler 108 before it is discharged at a second temperature 136. The process fluid 144 then flows to a process fluid consumer 126 where that process fluid 144 is used for some purpose. After the process fluid 144 is used, it is returned to the process fluid supply 130 or discharged from the system. [0029] The process fluid consumer 126 in the two process fluid cycles 150 may be the same consumer or may be different consumers. In addition, depending upon the desired process fluid consumer 126, the first temperature 134 and the second temperature 136 may be equal to one another or may be different. In one example, the process fluid 144 is water and the process fluid consumers 126 are hot water users. [0030] A controller 128 may be used to control the position of the multi-position valve 138 based at least in part on the first temperature 134 and the second temperature 136. Thus, the controller 128 can move the multi-position valve 138 to maintain the first temperature 134 and the second temperature 136 at a desired temperature and/or maintain them at a temperature in which they are equal to one another. The distributor 132 may include other components such as flow control valves, bypass valves, sensors, and the like that allow the controller 128 to achieve the desired first temperature 134 and the desired second temperature 136 while also maintaining a desired flow rate. [0031] FIG. 2 illustrates a process for operating a power conversion system 200 that includes directing a working fluid through a Brayton cycle to produce electrical power, the Brayton cycle including an intercooler and a secondary heat exchanger 202. The process further includes operating a nuclear reactor to generate heat as shown in block 204 and directing a flow of hot fluid through the nuclear reactor and the Brayton cycle to transfer thermal energy from the nuclear reactor to the Brayton cycle as shown in block 206. In block 208, the process for Docket No. 2023PF12321 operating a power conversion system 200 directs a process fluid to a distributor, the distributor then operates to direct a first portion of the working fluid to the secondary heat exchanger to produce a first flow of hot process fluid having a first temperature, and to direct a second portion of the working fluid to the intercooler to produce a second flow of hot process fluid having a second temperature as shown in block 210. In block 212, the process for operating a power conversion system 200 varies the operation of the distributor to maintain the first temperature at a first desired temperature and the second temperature at a second desired temperature. [0032] In operation, a heat source 124 such as a small modular reactor (SMR) is operated to generate thermal energy. At the same time, a Brayton cycle 102 is operated. The Brayton cycle 102 draws in working fluid 142 in the form of air and compresses it in a low-pressure compressor 106. The partially compressed working fluid 142 then flows through the intercooler 108 to be cooled and into the high-pressure compressor 110 where the compression process is completed. The fully compressed working fluid 142 next passes through the recuperator 112 where it is preheated before entering the primary heat exchanger 114. Within the primary heat exchanger 114, the flow of hot fluid 140 is used to fully heat the working fluid 142 so that it is discharged at a temperature sufficient to achieve a desired turbine inlet temperature. The quantity and pressure of the working fluid 142 as well as the setpoints of the heat source 124 are controlled to achieve the desired exit temperature at the primary heat exchanger 114 at a desired flow rate for the working fluid 142. Next, the fully compressed and heated working fluid 142 passes through the expander 116 which operates to convert a portion of the thermal and pressure energy of the working fluid 142 into rotation of the attached generator 118 which in turn produces the desired electrical power. The expander 116 or another similar expander or turbine may also be driven by the working fluid 142 to drive the low-pressure compressor 106 and/or the high-pressure compressor 110. [0033] After passing through the expander 116, the working fluid 142 passes through the recuperator 112 where some of the remaining thermal energy is used to preheat the working fluid 142 before it flows into the primary heat exchanger 114, and through the secondary heat exchanger 120 where still more of the thermal energy of the working fluid 142 is extracted and used before the working fluid 142 is discharged from the Brayton cycle 102. Docket No. 2023PF12321 [0034] In some arrangements, process fluid 144 can also be heated using the waste heat from the Brayton cycle 102. In the illustrated construction, the process fluid 144 is delivered to the distributor 132 which operates to direct a first portion of the process fluid 144 to the secondary heat exchanger 120 where it is heated to produce a first flow of hot process fluid. The first flow of hot process fluid exits the secondary heat exchanger 120 at the first temperature 134 and is directed to the process fluid consumer 126 for use. The distributor 132 operates to direct a second portion of the process fluid 144 to the intercooler 108 where it is heated and discharged at the second temperature 136 to define a second flow of hot process fluid. The second flow of hot process fluid flows to the process fluid consumer 126 where it used. As noted, the two flows could flow to a single process fluid consumer 126 or to two different process fluid consumers 126 as may be desired. [0035] The controller 128 operates to vary the portion of flow to the intercooler 108 and to the secondary heat exchanger 120 to maintain the first temperature at a first desired temperature and to maintain the second temperature at a second desired temperature, where the second desired temperature may be the same as the first desired temperature. [0036] The distributor 132 includes a multi-position valve 138 and may include additional valves and flow control devices that allow the distributor 132 to control the flow rate, and thereby the first temperature 134 and the second temperature 136 during operation and under varying operating conditions. [0037] In another construction, a supercritical carbon dioxide (SCO2) cycle may be used in place of or in conjunction with the Brayton cycle 102. Supercritical carbon dioxide (SCO2) is a working fluid that can be used in power generation systems. SCO2 refers to carbon dioxide gas that is brought to a supercritical state, where it exhibits unique properties that make it suitable for power applications. When carbon dioxide is heated and pressurized above its critical point (31°C and 7.38 MPa), it transitions into a supercritical state where it displays properties of both a gas and a liquid. In this state, SCO2 has a high density like a liquid, but it flows like a gas and can efficiently transfer heat. SCO2 offers several advantages over traditional working fluids, such as steam, in power generation. Firstly, it has a higher efficiency due to its higher density, which allows for more compact power generation equipment and reduces energy losses during heat transfer. Secondly, SCO2 has excellent heat transfer properties, enabling effective heat exchange with heat sources and sinks. Additionally, SCO2 Docket No. 2023PF12321 can operate at lower temperatures, making it suitable for diverse heat sources, including waste heat or solar energy. By utilizing SCO2 in power generation systems, energy efficiency can be improved, resulting in reduced emissions and increased power generation capacity. The adaptability and potential for integration with various heat sources make SCO2 an attractive option for sustainable and efficient power generation. [0038] Using SCO2 may not necessarily increase efficiency, but it may allow for more compact turbomachinery which would help with overall plant economics. Also, as the smaller turbines may allow for considerations such as an independent cycle for waste heat recovery or utilizing cascaded cycles for the higher fusion energy recovery process. Finally, SCO2 could be utilized as a coolant in one or more of the coolant loops to efficiently transfer heat between the various loops. [0039] The arrangement illustrated in FIG. 1 is capable of delivering heated process fluid 144 to one or more process fluid consumers 126. In the illustrated construction, two process fluid consumers 126 receive a flow from two separate heat exchangers. However, other arrangements could employ three or more process fluid cycles 150 as may be required by the particular application. Additionally, each of the intercooler 108 and the secondary heat exchanger 120 are sized and selected to provide the desired first temperature 134 and second temperature 136. In many applications, it is desirable that the first temperature 134 and the second temperature 136 be equal. However, other arrangements could provide process fluid 144 to each of the process fluid consumers 126 at different temperatures if desired. Thus, the illustrated system generates useable electrical power while also providing process fluid 144 at one or more desired temperatures. [0040] Although an exemplary embodiment of the present disclosure has been described in detail, those skilled in the art will understand that various changes, substitutions, variations, and improvements disclosed herein may be made without departing from the spirit and scope of the disclosure in its broadest form. [0041] None of the description in the present application should be read as implying that any particular element, step, act, or function is an essential element, which must be included in the claim scope: the scope of patented subject matter is defined only by the allowed Docket No. 2023PF12321 claims. Moreover, none of these claims are intended to invoke a means plus function claim construction unless the exact words "means for" are followed by a participle.

Claims

Docket No. 2023PF12321 CLAIMS What is claimed is: 1. A power conversion system comprising: a heat source operable to provide a flow of hot fluid; a generator operable to produce electrical power in response to rotation; a low-pressure compressor operable to compress a working fluid to a first pressure; a high-pressure compressor operable to compress the working fluid from the first pressure to a second pressure; an intercooler arranged to receive the working fluid from the low-pressure compressor and discharging the working fluid to the high-pressure compressor; a primary heat exchanger arranged to receive the flow of hot fluid and the working fluid and to discharge a hot working fluid; an expander operable to rotate the generator in response to the passage of the hot working fluid therethrough; a secondary heat exchanger coupled to the expander to receive the flow of hot working fluid therefrom; and a distributor movable to any point between a first position in which a process fluid is directed to the secondary heat exchanger and discharged therefrom at a first temperature, and a second position in which the process fluid is directed to the intercooler and discharged therefrom at a second temperature. 2. The power conversion system of claim 1, wherein the heat source includes a nuclear reactor that operates to heat the flow of hot fluid. 3. The power conversion system of claim 2, wherein the nuclear reactor includes a primary coolant loop that cools the nuclear reactor and heats the flow of hot fluid. 4. The power conversion system of claim 1, wherein the expander includes a multi- stage turbine. 5. The power conversion system of claim 4, wherein the multi-stage turbine includes two axial flow turbine stages. Docket No. 2023PF12321 6. The power conversion system of claim 1, wherein the distributor includes a multi-position valve operable to direct a first percentage of the process fluid to the secondary heat exchanger and a second percentage of the process fluid to the intercooler. 7. The power conversion system of claim 6, wherein the position of the distributor is selected to vary the first percentage and the second percentage such that the first temperature and the second temperature are equal to one another. 8. The power conversion system of claim 1, further comprising a controller operable to vary the position of the distributor in response to the first temperature of the process fluid exiting the secondary heat exchanger and the second temperature of the process fluid exiting the intercooler to vary the flow rate of process fluid to each of the intercooler and the secondary heat exchanger. 9. The power conversion system of claim 1, further comprising a recuperator positioned to receive the flow of hot working fluid directly from the expander and to direct the flow of hot working fluid from the recuperator to the secondary heat exchanger, the recuperator operable to heat the working fluid prior to its entry into the primary heat exchanger. 10. The power conversion system of claim 1, wherein the low-pressure compressor includes multiple axial flow compression stages. 11. The power conversion system of claim 1, wherein the high-pressure compressor includes multiple axial flow compression stages. 12. The power conversion system of claim 1, wherein the first temperature and the second temperature are different from one another.

Docket No. 2023PF12321 13. A power conversion system comprising: a Brayton cycle using a working fluid to generate electrical power, the Brayton cycle including an intercooler and a secondary heat exchanger; a heat source operable outside of the Brayton cycle to generate heat; a flow of hot fluid operable to transfer heat from the heat source to the Brayton cycle; a process fluid supply operable to deliver a process fluid; a distributor positioned to receive the process fluid and operable to deliver a first portion of the process fluid to the secondary heat exchanger to produce a first flow of hot process fluid having a first temperature, and to deliver a second portion of the process fluid to the intercooler to produce a second flow of hot process fluid having a second temperature; and a controller operable to adjust the distributor to vary the first portion and the second portion to maintain the first temperature at a first desired vale and to maintain the second temperature at a second desired value. 14. The power conversion system of claim 13, wherein the heat source includes a nuclear reactor that operates to heat the flow of hot fluid. 15. The power conversion system of claim 13, wherein the distributor includes a multi-position valve operable to direct the first portion of the process fluid to the secondary heat exchanger and the second portion of the process fluid to the intercooler. 16. The power conversion system of claim 15, wherein the position of the multi- position valve is selected to vary the first portion and the second portion such that the first temperature and the second temperature are equal to one another. 17. The power conversion system of claim 15, wherein the controller is operable to vary the position of the distributor in response to the first temperature and the second temperature to vary a flow rate of process fluid to each of the intercooler and the secondary heat exchanger. 18. The power conversion system of claim 13, wherein the first temperature and the second temperature are different from one another. Docket No. 2023PF12321 19. A method of operating a power conversion system, the method comprising: directing a working fluid through a Brayton cycle to produce electrical power, the Brayton cycle including an intercooler and a secondary heat exchanger; operating a nuclear reactor to generate heat; directing a flow of hot fluid through the nuclear reactor and the Brayton cycle to transfer thermal energy from the nuclear reactor to the Brayton cycle; directing a process fluid to a distributor; operating the distributor to direct a first portion of the working fluid to the secondary heat exchanger to produce a first flow of hot process fluid having a first temperature, and to direct a second portion of the working fluid to the intercooler to produce a second flow of hot process fluid having a second temperature; and varying the operation of the distributor to maintain the first temperature at a first desired temperature and the second temperature at a second desired temperature. 20. The method of claim 19, further comprising varying the operation of the distributor in response to the first temperature and the second temperature to adjust the first portion and the second portion to maintain the first temperature at the first desired temperature and the second temperature at the second desired temperature, and wherein the second desired temperature is equal to the first desired temperature.