Heat pump system and equipment based on reverse Brayton cycle

Abstract

The invention relates to the technical field of heat pumps, and provides a heat pump system and equipment based on reverse Brayton cycle, and the system comprises a compressor mechanism, a heat regenerator and an expander mechanism which are connected into a loop through working medium pipelines; the compressor mechanism comprises n compressors and n-1 intercoolers which are connected in series and alternately arranged; in the working medium flow direction, the first-stage compressor is connected with the low-temperature outlet end of the heat regenerator, and the last-stage compressor is connected with the high-temperature inlet end of the heat regenerator; the expander mechanism comprises m expanders and m-1 reheaters which are connected in series and alternately arranged; in the working medium flow direction, the first-stage expander is connected with the high-temperature outlet end of the heat regenerator, and the last-stage expander is connected with the low-temperature inlet end of the heat regenerator; m and n are integers greater than 0 and at least one is greater than 1. Through the arrangement, the heat pump can utilize a constant-temperature heat source, the output power is more stable, and the purpose of higher efficiency is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of heat pumps, and in particular to a heat pump system and equipment based on a reverse Brayton cycle. Background Art

[0002] With the growth of global energy demand and the improvement of environmental protection awareness, efficient and environmentally friendly energy conversion and utilization technologies have become a hot topic of research. As a technology that can convert low-level thermal energy into high-level thermal energy, heat pump technology has shown great potential in energy saving and consumption reduction. The reverse Brayton cycle heat pump is a new type of heat pump based on the Brayton cycle. Compared with traditional heat pump technologies such as air source heat pumps, water source heat pumps and ground source heat pumps, it has the characteristics of wide application range, low construction difficulty, no pollution to the environment, high efficiency, high energy saving and environmental protection, etc., and has attracted the attention of academia and industry.

[0003] In the related art, refer to Figure 1 The Brayton cycle heat pump generally includes a compressor 10, a condenser 11, a regenerator 12, an expander 13 and a cold box 14 connected as a loop by a working fluid pipeline. When working, the gas working fluid first enters the compressor 10, where the working fluid is adiabatically compressed. The compressed gas then enters the condenser 11 for cooling, and then enters the regenerator 12. The gas temperature in the regenerator 12 is greatly reduced, and then enters the expander 13. In the expander 13, the working fluid adiabatically expands to do work externally, and then enters the cold box 14 for refrigeration. After the low-temperature gas absorbs heat in the cold box 14, it enters the regenerator 12 to absorb heat, completing a single cycle, and then enters the compressor 10 to continue the cycle (such as Figure 2 as shown).

[0004] However, in the above-mentioned related technologies, the heat release process of the working fluid in the condenser 11 and the heat absorption process in the cold box 14 are both processes in which the temperature changes greatly, and the heat absorption and heat release rate of the working fluid is related to its temperature. When the working fluid temperature changes, the instantaneous cooling or heating power of the system will change, and the power output will be unstable. Summary of the invention

[0005] The present invention provides a heat pump system and equipment based on a reverse Brayton cycle, which are used to solve the defect of unstable output power of the heat pump in the prior art and can improve the stability of power output.

[0006] The present invention provides a heat pump system based on a reverse Brayton cycle, comprising: a compressor mechanism, a regenerator and an expander mechanism connected as a loop through a working fluid pipeline; The compressor mechanism comprises n compressors and n-1 intercoolers which are arranged in series and alternately; in the working medium flow direction, the first-stage compressor is connected to the low-temperature outlet end of the regenerator, and the last-stage compressor is connected to the high-temperature inlet end of the regenerator; The expander mechanism comprises m expanders and m-1 reheaters which are arranged in series and alternately; in the working medium flow direction, the first-stage expander is connected to the high-temperature outlet end of the reheater, and the last-stage expander is connected to the low-temperature inlet end of the reheater; Both m and n are integers greater than 0 and at least one of them is greater than 1.

[0007] According to a heat pump system based on a reverse Brayton cycle provided by the present invention, the number n of the compressors is greater than 1; the compressor mechanism further includes at least one first valve connected between the plurality of the compressors, and the compressor and the intercooler located upstream of each of the first valves constitute a compressor module; the compressor module includes at least two of the compressors arranged alternately and at least one intercooler located between adjacent compressors; It also includes at least one first branch, a first end of the first branch is connected to the upstream second end of the first valve and communicates with the high-temperature inlet end of the regenerator, and a first control valve is connected to the first branch.

[0008] According to a heat pump system based on a reverse Brayton cycle provided by the present invention, the working fluid pipeline includes a high-pressure section located between the final-stage compressor and the regenerator; the second end of the first branch is connected to the high-pressure section.

[0009] According to a heat pump system based on a reverse Brayton cycle provided by the present invention, the number of expanders m is greater than 1; the expander mechanism further includes at least one second valve connected between the plurality of expanders, and the expander and the reheater located upstream of each second valve constitute an expander module; the expander module includes at least two expanders arranged alternately and at least one reheater located between adjacent expanders; It also includes at least one second branch, a first end of the second branch is connected to the upstream of the second valve, a second end is connected to the low-temperature inlet end of the regenerator, and a first control valve is connected to the first branch.

[0010] According to a heat pump system based on a reverse Brayton cycle provided by the present invention, the working fluid pipeline includes a low-pressure section located between the final-stage expander and the regenerator; the second end of the second branch is connected to the low-pressure section.

[0011] According to a heat pump system based on a reverse Brayton cycle provided by the present invention, a working medium inlet is provided on the first-stage compressor.

[0012] According to a heat pump system based on a reverse Brayton cycle provided by the present invention, the number n of the compressors is greater than 1, and the number m of the expanders is greater than 1; Or, the number n of the compressors is greater than 1, and the number m of the expanders is equal to 1; Alternatively, the number n of the compressors is equal to 1, and the number m of the expanders is greater than 1.

[0013] According to a heat pump system based on a reverse Brayton cycle provided by the present invention, the expander includes an expander or a throttling device.

[0014] According to a heat pump system based on a reverse Brayton cycle provided by the present invention, the compressor includes a positive displacement compressor, a dynamic compressor or a thermal compressor.

[0015] The present invention also provides a device, comprising any one of the heat pump systems based on the reverse Brayton cycle described above.

[0016] Beneficial effects: 1. When the number of compressors n is greater than 1, the gaseous working medium first enters the first-stage compressor and is adiabatically compressed in the first-stage compressor, then enters the intercooler to release a small amount of compression heat, the working medium temperature drops slightly, and then enters the next-stage compressor to be adiabatically compressed. After repeating this process, it enters the regenerator through the final compressor to exchange heat with the low-temperature working medium, and the temperature of the gaseous working medium is greatly reduced. The cooled working medium enters the expander mechanism. In the above process, the heat pump can output heat through the intercooler, and the heat release process is approximately a constant temperature process, so that the heat pump can stably output heating power.

[0017] 2. When the number of expanders m is greater than 1, the cooled gas medium first enters the first-stage expander, where the gas expands adiabatically. The expanded low-temperature gas enters the reheater to absorb heat, causing the temperature to rise slightly and output cooling capacity, and then enters the next-stage expander to adiabatically expand and cool down. After repeating this process, it enters the regenerator through the final-stage expander to exchange heat with the high-temperature medium, causing the temperature of the gas medium to rise significantly. The heated medium enters the compressor mechanism. In the above process, the heat pump can absorb heat and output cooling capacity through the reheater, and the heat absorption process is approximately a constant temperature process, so that the heat pump can use a constant temperature heat source and can output cooling power stably.

[0018] 3. When the number of compressors n is greater than 1 and the number of expanders m is greater than 1, the heat absorption and release processes of the working fluid can be approximated as constant temperature processes, so that the heat pump can use a constant temperature heat source, and the power output of cooling or heating is more stable, achieving a higher efficiency.

[0019] 4. The use of constant temperature heat source by heat pump can greatly broaden the selection range of gas working fluids. Heat pumps in related technologies need temperature changes in the heat absorption stage. If you want to use a constant temperature heat source, you need to use ammonia, alkanes and other working fluids with phase change characteristics, so that the heat absorption stage of the heat pump is a constant temperature process; and in the embodiment of the present invention, through the use of multi-stage expansion and reheater, the temperature of the heat pump in the heat absorption stage is approximately constant temperature, thus breaking the above limitations. The choice of working fluid is no longer limited to working fluids with phase change characteristics, and air, nitrogen and other environmentally friendly gas working fluids can be used, and the raw materials are easy to obtain and the cost is low.

[0020] 5. The arrangement of the first branch and the second branch facilitates the maintenance of the heat pump and the adjustment of the number of stages of the compressor or the expander. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 This is a schematic diagram of the structure of a Brayton heat pump in the related technology. Figure 2 It is the working fluid cycle diagram of the Brayton heat pump in the related technology.

[0023] Figure 3 It is a schematic diagram of the structure of a heat pump system based on a reverse Brayton cycle provided in Example 1 of the present invention.

[0024] Figure 4 This is a working fluid cycle diagram of a heat pump system based on a reverse Brayton cycle provided in Example 1 of the present invention.

[0025] Figure 5 It is a schematic diagram of the structure of a heat pump system based on a reverse Brayton cycle provided in Example 2 of the present invention.

[0026] Figure 6 This is a working fluid cycle diagram of a heat pump system based on a reverse Brayton cycle provided in Example 2 of the present invention.

[0027] Figure 7 It is a schematic diagram of the structure of a heat pump system based on a reverse Brayton cycle provided in Example 3 of the present invention.

[0028] Figure 8 This is a working fluid cycle diagram of a heat pump system based on a reverse Brayton cycle provided in Example 3 of the present invention.

[0029] Reference numerals: 10. Compressor; 11. Condenser; 12. Regenerator; 13. Expander; 14. Cold box; 20. Working fluid pipeline; 200. High-pressure section; 201. Low-pressure section; 21. Compressor; 210. Working fluid inlet; 22. Intercooler; 23. Regenerator; 24. Expander; 25. Reheater; 26. First valve; 27. First branch; 270. First control valve; 28. Second valve; 29. ​​Second branch; 290. Second control valve. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In order to facilitate the understanding of the heat pump system and equipment based on the reverse Brayton cycle provided by the present invention, its application background is first introduced. The reverse Brayton cycle heat pump is a new type of heat pump based on the Brayton cycle. Compared with traditional heat pump technologies such as air source heat pumps, water source heat pumps and ground source heat pumps, it has the advantages of wide application range, low construction difficulty, no pollution to the environment, high efficiency, high energy saving and environmental protection.

[0032] In the related art, refer to Figure 1 The Brayton cycle heat pump generally includes a compressor 10, a condenser 11, a regenerator 12, an expander 13 and a cold box 14 connected by a working fluid pipeline. Figure 2 The gaseous working medium first enters the compressor 10, where the working medium is adiabatically compressed. The compressed gas then enters the condenser 11 for cooling, and then enters the regenerator 12. The gas temperature is greatly reduced in the regenerator 12. The gas then enters the expander 13. In the expander 13, the working medium adiabatically expands to do work externally, and then enters the cold box 14 for refrigeration. The low-temperature gas absorbs heat in the cold box 14 and then enters the regenerator 12 for refrigeration, completing a single cycle. The gas then enters the compressor 10 to continue the cycle.

[0033] However, in the above-mentioned related technologies, the heat release process of the working fluid in the condenser 11 and the heat absorption process in the cold box 14 are both processes in which the temperature changes greatly, and the heat absorption and heat release rate of the working fluid is related to its temperature. When the working fluid temperature changes, the instantaneous cooling or heating power of the system will change, and the power output will be unstable.

[0034] In view of the above problems, the present invention provides a heat pump system and equipment based on a reverse Brayton cycle, which can provide stability of the heat pump output power.

[0035] Combine the following Figure 3-Figure 8 The heat pump system and apparatus based on the reverse Brayton cycle of the present invention are described.

[0036] Reference Figures 3 to 8 , a heat pump system based on a reverse Brayton cycle, comprising a compressor mechanism, a regenerator 23 and an expander mechanism connected as a loop through a working fluid pipeline 20; wherein the compressor mechanism comprises n compressors 21 and n-1 intercoolers 22 arranged in series and alternately, in the flow direction of the working fluid, the first-stage compressor 21 is connected to the low-temperature outlet end of the regenerator 23, and the last-stage compressor 21 is connected to the high-temperature inlet end of the regenerator 23; the expander 24 comprises m expanders 24 and m-1 reheaters 25 arranged in series and alternately, in the flow direction of the working fluid, the first-stage expander 24 is connected to the high-temperature outlet end of the regenerator 23, and the last-stage expander 24 is connected to the low-temperature inlet end of the regenerator 23; n and m are both integers greater than 0 and at least one of them is greater than 1.

[0037] In actual operation, when the number n of compressors 21 is greater than 1, the gaseous working medium first enters the first-stage compressor 21 and is adiabatically compressed in the first-stage compressor 21, then enters the intermediate cooler 22 to release a small amount of compression heat, the working medium temperature drops slightly, and then enters the next-stage compressor 21 to be adiabatically compressed. After repeating this process, it enters the regenerator 23 through the final compressor 21 to exchange heat with the low-temperature working medium, and the temperature of the gaseous working medium is greatly reduced. The cooled working medium enters the expander mechanism. In the above process, the heat pump can output heat through the intermediate cooler 22, and the heat release process is approximately a constant temperature process, so that the heat pump can stably output heating power.

[0038] When the number m of expanders 24 is greater than 1, the gaseous working medium after cooling first enters the first-stage expander 24, and the gas expands adiabatically in the first-stage expander 24. The expanded low-temperature gas enters the reheater 25 to absorb heat, causing the temperature to rise slightly and output cooling capacity, and then enters the next-stage expander 24 to adiabatically expand and cool down. After repeating this process, it enters the regenerator 23 through the final-stage expander 24 to exchange heat with the high-temperature working medium, and the temperature of the gas working medium rises significantly. The heated working medium enters the compressor mechanism. In the above process, the heat pump can absorb heat and output cooling capacity through the reheater 25, and the heat absorption process is approximately a constant temperature process, so that the heat pump can use a constant temperature heat source and can stably output cooling power.

[0039] When the number n of compressors 21 is greater than 1 and the number m of expanders 24 is greater than 1, the heat absorption and release processes of the working fluid can be approximated as constant temperature processes, so that the heat pump can utilize a constant temperature heat source, and the power output of cooling and heating is more stable, achieving a higher efficiency.

[0040] In addition, the use of a constant temperature heat source by a heat pump can greatly broaden the selection range of gaseous working fluids. The heat pumps in related technologies have temperature changes in the heat absorption stage. If a constant temperature heat source is to be used, it is necessary to use ammonia, alkanes and other working fluids with phase change characteristics, so that the heat absorption stage of the heat pump is a constant temperature process; and in the embodiment of the present invention, through the use of a multi-stage expander 24 and a reheater 25, the temperature of the heat pump in the heat absorption stage is approximately constant temperature, thereby breaking the above limitations. The choice of working fluid is no longer limited to working fluids with phase change characteristics, and air, nitrogen and other environmentally friendly gaseous working fluids can be used, and the raw materials are easy to obtain and the cost is low.

[0041] It is understandable that the number n of compressors 21 and the number m of expanders 24 can be set according to actual working conditions to meet different actual needs.

[0042] Example 1 Reference Figure 3 and Figure 4 In this embodiment, the number n of the compressors 21 is greater than 1, and the number m of the expanders 24 is equal to 1. The inlet of the first-stage compressor 21 is connected to the low-temperature outlet end of the regenerator 23, the outlet of the final-stage compressor 21 is connected to the high-temperature inlet end of the regenerator 23, the inlet of the expander 24 is connected to the high-temperature outlet end of the regenerator 23, and the outlet is connected to the low-temperature inlet end of the regenerator 23. The high-temperature working medium flowing out of the final-stage compressor 21 and the low-temperature working medium flowing out of the expander 24 perform heat exchange in the regenerator 23.

[0043] With such arrangement, the working fluid releases a small amount of compression heat when passing through the intercooler 22, the working fluid temperature slightly decreases and outputs heat to the outside, and then the temperature rises again after being compressed by the lower-stage compressor 21, and this cycle repeats, so that the temperature curve of the working fluid heat release process is sawtooth-shaped, and the temperature remains approximately constant, thereby achieving constant-temperature heat output through the intercooler 22 to stabilize the heating power.

[0044] It should be noted that the specific number of compressors 21 and corresponding intercoolers 22 can be arranged according to actual needs, and no specific limitation is made in the embodiment of the present invention.

[0045] Example 2 Reference Figure 5 and Figure 6 In this embodiment, the number n of the compressors 21 is equal to 1, and the number m of the expanders 24 is greater than 1. The inlet of the compressor 21 is connected to the low-temperature outlet end of the regenerator 23, and the outlet is connected to the high-temperature inlet end of the regenerator 23. The inlet of the first-stage expander 24 is connected to the high-temperature outlet end of the regenerator 23, and the outlet of the final-stage compressor 21 is connected to the low-temperature inlet end of the regenerator 23. The high-temperature working fluid flowing out of the compressor 21 and the low-temperature working fluid flowing out of the final-stage expander 24 perform heat exchange in the regenerator 23.

[0046] With such arrangement, when the working fluid absorbs heat through the reheater 25, it releases a small amount of cold to make its own temperature rise slightly, and then the temperature decreases after passing through the lower-stage expander 24, and so on and so forth, so that the temperature curve of the working fluid heat absorption process is sawtooth-shaped, and the temperature remains approximately constant, thereby achieving constant-temperature output of cold through the reheater 25, thereby stabilizing the refrigeration power and enabling the heat pump to utilize a constant-temperature heat source.

[0047] It should be noted that the specific number of expanders 24 and corresponding reheaters 25 can be arranged according to actual needs, and no specific limitation is made in the embodiment of the present invention.

[0048] Example 3 In this embodiment, refer to Figure 7 and Figure 8 , the number n of compressors 21 is greater than 1, and the number m of expanders 24 is greater than 1. Through the above technical solution, the temperature of the gas working medium is approximately kept constant during the compression between the multi-stage compressors 21 and the cooling by the multi-stage intercooler 22, so that the constant temperature output of heat is achieved through the intercooler 22 to stabilize the heating power. The working medium cooled by the regenerator 23 enters the expander mechanism, and the temperature of the gas working medium is approximately kept constant during the expansion and cooling between the multi-stage expanders 24 and the heating by the multi-stage reheater 25, so that the constant temperature output of cooling capacity is achieved through the reheater 25 to stabilize the cooling power and enable the heat pump to use a constant temperature heat source.

[0049] It should be noted that the specific number n of compressors 21 and the specific number m of expanders 24 may be the same or different, and may be specifically arranged according to actual needs, and are not specifically limited in the embodiment of the present invention.

[0050] In some optional embodiments, according to different working principles, the compressor 21 includes but is not limited to any device capable of compressing the gaseous working medium, such as a positive displacement compressor, a dynamic compressor or a thermal compressor.

[0051] In some optional embodiments, the expander 24 may be an expander, so that the working fluid can perform external work while expanding adiabatically, and a throttling device may be used to control the temperature and pressure of the gas working fluid by adjusting the flow rate.

[0052] Specifically, the throttling device includes but is not limited to an expansion valve, a capillary tube, and the like.

[0053] In one embodiment of the present invention, the regenerator 23 can be a counter-flow regenerator, which has a cold working medium flow channel and a hot working medium flow channel, wherein the cold working medium flow channel is used for the cold working medium flowing out of the final stage expander 24 to pass through, and the hot working medium flow channel is used for the hot working medium flowing out of the final stage compressor 21 to pass through, and the cold working medium and the hot working medium flow in opposite directions to exchange heat.

[0054] It should be pointed out here that the above is only a brief description of the structure or principle of the counterflow regenerator. The embodiment of the present invention only utilizes the heat exchange function of the counterflow regenerator but does not make any changes to its structure or principle. The specific structure of the counterflow regenerator is not the main invention point of the present invention. Therefore, the specific structure of the counterflow regenerator can refer to the prior art and will not be repeated in the embodiment of the present invention.

[0055] It is understandable that the regenerator 23 includes but is not limited to the counterflow regenerator listed above. As long as other forms of regenerators 23 can achieve heat exchange between cold working fluid and hot working fluid, they are also applicable and will not be listed one by one in the embodiments of the present invention.

[0056] In one embodiment of the present invention, referring to Figures 3 to 8 When the number n of compressors 21 is greater than 1, the compressor mechanism further includes at least one first valve 26 connected between the multiple compressors 21, and the compressor 21 and the intercooler 22 located upstream of each first valve 26 constitute a compressor module; the compressor module includes at least two compressors 21 arranged alternately and at least one intercooler 22 located between adjacent compressors 21; and further includes at least one first branch 27, a first end of the first branch 27 is connected to the upstream of the first valve 26, and a second end is connected to the high-temperature inlet end of the regenerator 23, and a first control valve 270 is connected to the first branch 27.

[0057] With such arrangement, after closing the first valve 26 and opening the first control valve 270, the flow path of the working fluid changes, and the compressor module located upstream of the first valve 26 maintains normal operation, while the compressor 21 located downstream of the first valve 26 can be shut down for maintenance, so that the heat pump can maintain normal operation during the maintenance process, which is conducive to improving the convenience of maintenance and replacement of the compressor 21. In addition, by controlling the opening and closing states of the first valve 26 and the first control valve 270, the number of stages of the compressor 21 can be adjusted, thereby regulating the heating power.

[0058] It is understandable that the specific number of the first valve 26 and the first branch 27 can be set according to the actual working conditions and heating power adjustment requirements, and is not specifically limited in the embodiment of the present invention.

[0059] In one embodiment of the present invention, the working fluid pipeline 20 includes a high-pressure section 200 located between the final compressor 21 and the regenerator 23; the second end of the first branch 27 is connected to the high-pressure section 200. In this way, the connection between the first branch 27 and the regenerator 23 can be facilitated.

[0060] In one embodiment of the present invention, when the number m of expanders 24 is greater than 1, the expander mechanism also includes at least one second valve 28 connected between the multiple expanders 24, and the expander 24 and the reheater 25 located upstream of each second valve 28 constitute an expander module; the expander module includes at least two expanders 24 arranged alternately and at least one reheater 25 located between adjacent compressors 21; and also includes at least one second branch 29, a first end of the second branch 29 is connected to the upstream of the second valve 28, and a second end is connected to the low-temperature inlet end of the reheater 23, and a second control valve 290 is connected to the second branch 29.

[0061] With such an arrangement, after closing the second valve 28 and opening the second control valve 290, the flow path of the working medium changes, and the expander module located upstream of the second valve 28 maintains normal operation, while the expander 24 located downstream of the second valve 28 can be shut down for maintenance, so that the heat pump can maintain normal operation during the maintenance process, which is conducive to improving the convenience of maintenance and replacement of the expander 24. In addition, by controlling the opening and closing states of the second valve 28 and the second control valve 290, the number of stages of the expander 24 can be adjusted, thereby regulating the refrigeration power.

[0062] In one embodiment of the present invention, the working fluid pipeline 20 includes a low-pressure section 201 between the final expander 24 and the regenerator 23; the second end of the second branch 29 is connected to the low-pressure section 201. In this way, the connection between the second branch 29 and the regenerator 23 can be facilitated.

[0063] It is understandable that the specific number of the second valve 28 and the second branch 29 can be set according to the actual working conditions and the cooling power adjustment requirements, and is not specifically limited in the embodiment of the present invention.

[0064] In one embodiment of the present invention, a working fluid inlet 210 is provided on the first-stage compressor 21, and new working fluid can be added to the heat pump system through the working fluid inlet 210 to solve the problem of working fluid loss in the system.

[0065] It is to be understood that, without mutual contradiction, those skilled in the art may combine and combine the different embodiments or examples and the features of the different embodiments or examples described in this specification.

[0066] The device provided by the present invention is described below. The device described below and the heat pump system based on the reverse Brayton cycle described above can be referred to each other.

[0067] A device comprises a heat pump system based on a reverse Brayton cycle provided by any one of the above embodiments.

[0068] Specifically, the above-mentioned equipment includes but is not limited to various forms of heating and cooling equipment.

[0069] Through the heat pump system and equipment based on the reverse Brayton cycle provided by the embodiment of the present invention, the gas working medium enters the intercooler 22 to release a small amount of compression heat and then enters the next-stage compressor 21 to be adiabatically compressed. This reciprocating process makes the heat release process of the intercooler 22 approximately a constant temperature process, so that the heat pump can stably output heating power; the gas working medium enters the reheater 25 to absorb a small amount of heat and then enters the next-stage expander 24 to expand and cool down. This reciprocating process makes the heat absorption process of the reheater 25 approximately a constant temperature process, so that the heat pump can utilize a constant temperature heat source and can stably output cooling power.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A heat pump system based on a reverse Brayton cycle, characterized in that: include: A compressor mechanism, a regenerator (23) and an expander mechanism connected as a loop via a working fluid pipeline (20); The compressor mechanism comprises n compressors (21) and n-1 intercoolers (22) which are arranged in series and alternately; in the working medium flow direction, the first-stage compressor (21) is connected to the low-temperature outlet end of the regenerator (23), and the last-stage compressor (21) is connected to the high-temperature inlet end of the regenerator (23); The expander mechanism comprises m expanders (24) and m-1 reheaters (25) which are arranged in series and alternately; in the working medium flow direction, the first-stage expander (24) is connected to the high-temperature outlet end of the reheater (23), and the last-stage expander (24) is connected to the low-temperature inlet end of the reheater (23); Both m and n are integers greater than 0 and at least one of them is greater than 1.

2. The heat pump system based on the reverse Brayton cycle according to claim 1, characterized in that: The number n of the compressors (21) is greater than 1; the compressor mechanism further comprises at least one first valve (26) connected between the plurality of compressors (21), and the compressor (21) and the intercooler (22) located upstream of each of the first valves (26) form a compressor module; The compressor module comprises at least two compressors (21) arranged alternately and at least one intercooler (22) located between adjacent compressors (21); It also includes at least one first branch (27), wherein a first end of the first branch (27) is connected to an upstream second end of the first valve (26) and is in communication with a high-temperature inlet end of the regenerator (23), and a first control valve (270) is connected to the first branch (27).

3. The heat pump system based on the reverse Brayton cycle according to claim 2, characterized in that: The working fluid pipeline (20) comprises a high-pressure section (200) located between the final-stage compressor (21) and the regenerator (23); the second end of the first branch (27) is connected to the high-pressure section (200).

4. The heat pump system based on the reverse Brayton cycle according to any one of claims 1 to 3, characterized in that: The number m of the expanders (24) is greater than 1; the expander mechanism further comprises at least one second valve (28) connected between the plurality of expanders (24), and the expander (24) and the reheater (25) located upstream of each of the second valves (28) constitute an expander module; The expander module comprises at least two expanders (24) arranged alternately and at least one reheater (25) located between adjacent expanders (24); It also includes at least one second branch (29), wherein a first end of the second branch (29) is connected to the upstream of the second valve (28), and a second end is connected to the low-temperature inlet end of the regenerator (23), and a second control valve (290) is connected to the first branch (27).

5. The heat pump system based on the reverse Brayton cycle according to claim 4, characterized in that: The working fluid pipeline (20) comprises a low-pressure section (201) located between the final-stage expander (24) and the regenerator (23); the second end of the second branch (29) is connected to the low-pressure section (201).

6. The heat pump system based on the reverse Brayton cycle according to claim 1, characterized in that: The first-stage compressor (21) is provided with a working medium inlet (210).

7. The heat pump system based on the reverse Brayton cycle according to claim 1, characterized in that: The number n of the compressors (21) is greater than 1, and the number m of the expanders (24) is greater than 1; Or, the number n of the compressors (21) is greater than 1, and the number m of the expanders (24) is equal to 1; Alternatively, the number n of the compressors (21) is equal to 1, and the number m of the expanders (24) is greater than 1.

8. The heat pump system based on the reverse Brayton cycle according to claim 1, characterized in that: The expander (24) comprises an expander or a throttling device.

9. The heat pump system based on the reverse Brayton cycle according to claim 1, characterized in that: The compressor (21) comprises a positive displacement compressor (21), a dynamic compressor (21) or a thermal compressor (21).

10. A device, characterized in that: A heat pump system based on a reverse Brayton cycle as described in any one of claims 1 to 9.

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