Heating, cooling and hot water supply system based on two-stage injection compression cycle and operation method

Abstract

The present invention relates to a heating, cooling and hot water supply system and operation method based on a two-stage ejector compression cycle, wherein a low-pressure compressor outlet, an intercooler inlet, a first three-way valve inlet, a high-pressure compressor, a first heat exchanger and a first ejector inlet are connected in series in sequence, and a first end of a third three-way valve is connected in series with a third heat exchanger, a throttle valve, a second heat exchanger and a first end of a second three-way valve in sequence; four interfaces of the first four-way reversing valve are respectively connected to the low-pressure compressor inlet, the second outlet of the first three-way valve, the second end of the second three-way valve and the second end of the third three-way valve; four interfaces of the second four-way reversing valve are respectively connected to the second ejector inlet, the ejector outlet, the third end of the second three-way valve and the third end of the third three-way valve. The present invention can meet the needs of indoor heating and domestic hot water in winter, and the needs of domestic hot water and indoor cooling in summer, and improves the cooling and heating efficiency of the system.

Description

Technical Field

[0001] The present invention relates to the technical field of heating, ventilation and refrigeration, and in particular to a heating, cooling and hot water supply system based on a two-stage injection compression cycle and an operating method thereof. Background Art

[0002] In most parts of my country, both residential and commercial buildings face demands for domestic hot water and cooling in the summer, and for domestic hot water and indoor heating in the winter. Meeting these demands often requires multiple systems, which are not only bulky but also wasteful. The two sets of equipment cannot operate efficiently simultaneously in both winter and summer, resulting in a waste of resources. Furthermore, the cooling and heating source devices in traditional air-conditioning systems are inefficient, particularly air-source heat pumps. Single-stage air-source heat pump water heaters experience a sharp drop in system efficiency in low-temperature environments due to the excessively high suction and exhaust pressure ratio. Summary of the Invention

[0003] In view of the shortcomings of the existing technology, the present invention provides a heating, cooling and hot water supply system and operation method based on a two-stage injection compression cycle, the purpose of which is to meet the versatility of use requirements in different seasons and improve system efficiency.

[0004] The technical solution adopted in the present invention is as follows:

[0005] In a first aspect, the present application provides a heating, cooling and hot water supply system based on a two-stage ejector compression cycle, comprising a low-pressure compressor, an intercooler, a first three-way valve, a high-pressure compressor, a first heat exchanger, an ejector, a second three-way valve, a first four-way reversing valve, a second four-way reversing valve, a second heat exchanger, a throttle valve, a third heat exchanger and a third three-way valve. The connection structure on the refrigerant side between the components is as follows:

[0006] The low-pressure stage compressor outlet and the intercooler inlet, the intercooler outlet and the first three-way valve inlet, the first outlet of the first three-way valve and the high-pressure stage compressor inlet, the high-pressure stage compressor outlet and the refrigerant side inlet of the first heat exchanger, and the refrigerant side outlet of the first heat exchanger and the first inlet of the ejector are connected in series in sequence;

[0007] The first end of the third three-way valve is connected in series with the third heat exchanger, the throttle valve, the second heat exchanger and the first end of the second three-way valve in sequence;

[0008] The four interfaces of the first four-way reversing valve are respectively connected to the inlet of the low-pressure stage compressor, the second outlet of the first three-way valve, the second end of the second three-way valve and the second end of the third three-way valve;

[0009] The four interfaces of the second four-way reversing valve are respectively connected to the second inlet of the injector, the outlet of the injector, the third end of the second three-way valve and the third end of the third three-way valve.

[0010] Further technical solutions are:

[0011] The heat exchange medium side of the first heat exchanger is connected to the user's domestic water circulation pipeline.

[0012] The heat exchange medium side of the second heat exchanger is connected to the user's air conditioning water circulation pipeline.

[0013] The heat exchange medium side of the third heat exchanger is outdoor air.

[0014] The second aspect of the present application provides an operating method for a heating, cooling and hot water supply system based on a two-stage injection compression cycle. By adjusting the first four-way reversing valve and the second four-way reversing valve, the switching between the winter operation mode and the summer operation mode is realized. In the winter operation mode, domestic hot water and indoor heating needs are met, and in the winter operation mode, domestic hot water and indoor cooling needs are met.

[0015] Further technical solutions are:

[0016] In the winter operation mode, the ejector outlet is connected to the third end of the second three-way valve through the second four-way reversing valve, and the third end of the third three-way valve is connected to the second inlet of the ejector. The second outlet of the first three-way valve is connected to the second end of the second three-way valve through the first four-way reversing valve, and the second end of the third three-way valve is connected to the inlet of the low-pressure stage compressor. The low-pressure stage compressor and the high-pressure stage compressor compress the refrigerant to a high-temperature and high-pressure state, and the refrigerant in the first heat exchanger is condensed to produce high-temperature domestic hot water on the heat exchange medium side. The ejector is used to increase the pressure of part of the refrigerant in the third heat exchanger to the pressure in the second heat exchanger, and the refrigerant is mixed with part of the medium-pressure refrigerant from the low-pressure stage compressor, condensed in the second heat exchanger, and formed into medium-temperature hot water on the heat exchange medium side for indoor low-temperature heating.

[0017] In the summer operation mode, the second outlet of the first three-way valve is connected to the second end of the third three-way valve through the first four-way reversing valve, and the second end of the second three-way valve is connected to the inlet of the low-pressure stage compressor. The third end of the third three-way valve is connected to the outlet of the ejector through the second four-way reversing valve, and the second inlet of the ejector is connected to the third end of the second three-way valve. The low-pressure stage compressor and the high-pressure stage compressor compress the refrigerant to a high-temperature and high-pressure state, and the refrigerant in the first heat exchanger is condensed to produce high-temperature domestic hot water on the heat exchange medium side. The ejector is used to increase the pressure of the refrigerant in the second heat exchanger to the pressure in the third heat exchanger, and the refrigerant is mixed with part of the refrigerant from the low-pressure stage compressor and condensed in the third heat exchanger. Thereafter, the throttle valve is used to throttle the refrigerant to a low-temperature and low-pressure state, and it evaporates in the second heat exchanger, and produces low-temperature chilled water on the heat exchange medium side for indoor cooling.

[0018] The beneficial effects of the present invention are as follows:

[0019] The system of the present invention can meet the needs of indoor heating and domestic hot water in winter, and the needs of domestic hot water and indoor cooling in summer, realizing that a set of equipment can meet the needs of HVAC equipment in home and commercial environments throughout the year. Compared with existing equipment, the equipment is simpler and the equipment utilization rate is higher, providing a new idea for home and commercial integrated HVAC equipment in this field.

[0020] When the system of the present invention is operated in winter, the ejector is used to increase the heating amount in the second heat exchanger and the system heating efficiency; when it is operated in summer, the ejector is used to increase the flow rate of the refrigerant in the second heat exchanger, thereby increasing the cooling capacity and the system cooling efficiency.

[0021] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the system structure of the present invention.

[0023] Figure 2 Schematic diagram of the system structure in the winter operation mode of the present invention.

[0024] Figure 3 Schematic diagram of the system structure in the summer operation mode of the present invention.

[0025] In the figure: 1. Low-pressure stage compressor; 2. Intercooler; 3. First three-way valve; 4. High-pressure stage compressor; 5. First heat exchanger; 6. Ejector; 7. Second three-way valve; 8. First four-way reversing valve; 9. Second four-way reversing valve; 10. Second heat exchanger; 11. Throttle valve; 12. Third heat exchanger; 13. Third three-way valve. DETAILED DESCRIPTION

[0026] The specific embodiments of the present invention are described below with reference to the accompanying drawings.

[0027] like Figure 1 As shown, this embodiment provides a heating and cooling hot water supply system based on a two-stage injection compression cycle, including a low-pressure stage compressor 1, an intercooler 2, a first three-way valve 3, a high-pressure stage compressor 4, a first heat exchanger 5, an ejector 6, a second three-way valve 7, a first four-way reversing valve 8, a second four-way reversing valve 9, a second heat exchanger 10, a throttle valve 11, a third heat exchanger 12 and a third three-way valve 13. The connection structure on the refrigerant side between the various components is as follows:

[0028] The outlet of the low-pressure stage compressor 1 is connected in series with the inlet of the intercooler 2, the outlet of the intercooler 2 is connected to the inlet of the first three-way valve 3, the first outlet of the first three-way valve 3 is connected to the inlet of the high-pressure stage compressor 4, the outlet of the high-pressure stage compressor 4 is connected to the refrigerant side inlet of the first heat exchanger 5, and the refrigerant side outlet of the first heat exchanger 5 is connected to the first inlet of the ejector 6 in sequence; the first end of the third three-way valve 13 is connected in series with the third heat exchanger 12, the throttle valve 11, the second heat exchanger 10, and the first end of the second three-way valve 7 in sequence; the four interfaces of the first four-way reversing valve 8 are respectively connected to the inlet of the low-pressure stage compressor 1, the second outlet of the first three-way valve 3, the second end of the second three-way valve 7, and the second end of the third three-way valve 13; the four interfaces of the second four-way reversing valve 9 are respectively connected to the second inlet of the ejector 6, the outlet of the ejector 6, the third end of the second three-way valve 7, and the third end of the third three-way valve 13;

[0029] The connection structure of the heat exchange medium side of each heat exchanger is:

[0030] The heat exchange medium side of the first heat exchanger 5 is connected to the user's domestic water circulation pipeline;

[0031] The heat exchange medium side of the second heat exchanger 10 is connected to the user's air conditioning water circulation pipeline;

[0032] The heat exchange medium side of the third heat exchanger 12 is outdoor air.

[0033] This embodiment also provides an operating method for a heating and cooling hot water supply system based on a two-stage injection compression cycle. By adjusting the first four-way reversing valve 8 and the second four-way reversing valve 9, switching between the winter operating mode and the summer operating mode is achieved. In the winter operating mode, domestic hot water and indoor heating needs are met, and in the winter operating mode, domestic hot water and indoor cooling needs are met.

[0034] like Figure 2 The following is the system structure in winter operation mode. The refrigerant flow direction is as follows: Figure 2 As indicated by the middle arrow, the outlet of the low-pressure compressor 1 is connected to the inlet of the intercooler 2, the outlet of the intercooler 2 is connected to the inlet of the first three-way valve 3, the first outlet of the first three-way valve 3 is connected to the inlet of the high-pressure compressor 4, the outlet of the high-pressure compressor 4 is connected to the refrigerant-side inlet of the first heat exchanger 5, and the refrigerant-side outlet of the first heat exchanger 5 is connected to the first inlet of the ejector 6 in sequence. The first end of the third three-way valve 13 is connected to the third heat exchanger 12, the throttle valve 11, the second heat exchanger 10, and the first end of the second three-way valve 7 in sequence. The outlet of the ejector 6 is connected to the third end of the second three-way valve 7 through the second four-way reversing valve 9, and the third end of the third three-way valve 13 is connected to the second inlet of the ejector 6. The second outlet of the first three-way valve 3 is connected to the second end of the second three-way valve 7 through the first four-way reversing valve 8, and the second end of the third three-way valve 13 is connected to the inlet of the low-pressure compressor 1.

[0035] See also Figure 2 In the legend, the refrigerant flowing out of the outlet of the high-pressure stage compressor 4, passing through the high-pressure stage compressor 4 and the first heat exchanger 5, and then entering the ejector 6 is a high-temperature and high-pressure refrigerant. The refrigerant flowing out of the throttle valve 11, passing through the third heat exchanger 12, the third three-way valve 13, the second four-way reversing valve 9, and the second inlet into the ejector 6, as well as the refrigerant flowing through the third three-way valve 13 and the first four-way reversing valve 8 into the low-pressure stage compressor 1 are low-temperature and low-pressure refrigerants. The refrigerant flowing out of the outlet of the low-pressure stage compressor 1, passing through the intercooler 2, the first three-way valve 3, and then passing through the first four-way reversing valve 8 and the second three-way valve 7 into the second heat exchanger 10 and arriving at the throttle valve 11, and the refrigerant flowing out of the ejector 6 outlet through the second four-way reversing valve 9 and the second three-way valve 7, entering the second heat exchanger 10 and arriving at the throttle valve 11 after the high-pressure and low-pressure refrigerants are mixed are medium-temperature and medium-pressure refrigerants.

[0036] During operation, the low-pressure compressor 1 and the high-pressure compressor 4 are used to compress the refrigerant to a high-temperature and high-pressure state, and the refrigerant in the first heat exchanger 5 is condensed to produce high-temperature domestic hot water on the heat exchange medium side. The ejector 6 is used to increase the pressure of part of the refrigerant in the third heat exchanger 12 to the pressure in the second heat exchanger 10, and mix it with part of the medium-pressure refrigerant from the low-pressure compressor 1, condense it in the second heat exchanger 10, and form medium-temperature hot water on the heat exchange medium side for indoor low-temperature heating.

[0037] Through the pressure-boosting effect of the ejector 6 and mixing with part of the medium-pressure refrigerant from the outlet of the low-pressure compressor (after being cooled by the intercooler) in the second heat exchanger 10, the heating capacity of the second heat exchanger 10 (medium-temperature condenser) is increased, thereby improving the heating efficiency of the system.

[0038] like Figure 3 The following is the system structure in summer operation mode. The refrigerant flow direction is as follows: Figure 3 As shown by the middle arrows, the outlet of the low-pressure stage compressor 1 is connected in series with the inlet of the intercooler 2, the outlet of the intercooler 2 is connected to the inlet of the first three-way valve 3, the first outlet of the first three-way valve 3 is connected to the inlet of the high-pressure stage compressor 4, the outlet of the high-pressure stage compressor 4 is connected to the refrigerant side inlet of the first heat exchanger 5, and the refrigerant side outlet of the first heat exchanger 5 is connected to the first inlet of the ejector 6 in sequence; the first end of the third three-way valve 13 is connected in series with the third heat exchanger 12, the throttle valve 11, the second heat exchanger 10, and the first end of the second three-way valve 7 in sequence; and the second outlet of the first three-way valve 3 is connected to the second end of the third three-way valve 13 through the first four-way reversing valve 8, and the second end of the second three-way valve 7 is connected to the inlet of the low-pressure stage compressor 1, and the third end of the third three-way valve 13 is connected to the outlet of the ejector 6 through the second four-way reversing valve 9, and the second inlet of the ejector 6 is connected to the third end of the second three-way valve 7.

[0039] See also Figure 3In the legend, the refrigerant flowing out of the outlet of the high-pressure stage compressor 4, passing through the high-pressure stage compressor 4 and the first heat exchanger 5, and then entering the ejector 6 is a high-temperature and high-pressure refrigerant. The refrigerant flowing out of the throttle valve 11, passing through the second heat exchanger 10, the second three-way valve 7, the second four-way reversing valve 9, and the second inlet into the ejector 6, as well as the refrigerant flowing through the second three-way valve 7 and the first four-way reversing valve 8 into the low-pressure stage compressor 1 are low-temperature and low-pressure refrigerants. The refrigerant flowing out of the outlet of the low-pressure stage compressor 1, passing through the intercooler 2, the first three-way valve 3, and then passing through the first four-way reversing valve 8 and the third three-way valve 13 into the third heat exchanger 12 and arriving at the throttle valve 11, and the refrigerant flowing out of the ejector 6 outlet after the high-pressure and low-pressure refrigerants are mixed, passing through the second four-way reversing valve 9 and the third three-way valve 13, entering the third heat exchanger 12 and arriving at the throttle valve 11 are medium-temperature and medium-pressure refrigerants.

[0040] During operation, the low-pressure compressor 1 and the high-pressure compressor 4 are used to compress the refrigerant to a high-temperature and high-pressure state, and the refrigerant in the first heat exchanger 5 is condensed to produce high-temperature domestic hot water on the heat exchange medium side. The ejector 6 is used to increase the pressure of the refrigerant in the second heat exchanger 10 to the pressure in the third heat exchanger 12, and mixed with part of the refrigerant from the low-pressure compressor 1, and condensed in the third heat exchanger 12. Thereafter, the throttle valve 11 is used to throttle the refrigerant to a low-temperature and low-pressure state, and evaporates in the second heat exchanger 10, and produces low-temperature chilled water on the heat exchange medium side for indoor cooling.

[0041] Through the pressure-boosting effect of the ejector 6, it is mixed with part of the medium-pressure refrigerant from the outlet of the low-pressure compressor (after being cooled by the intercooler) in the third heat exchanger 12 and enters the second heat exchanger 10 through the throttle valve 11, thereby increasing the flow rate of the refrigerant in the second heat exchanger 10, thereby improving the cooling capacity and the cooling efficiency of the system.

[0042] Those skilled in the art will understand that the foregoing descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will be able to modify the technical solutions described in the foregoing embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A heating and cooling hot water supply system based on a two-stage injection compression cycle, characterized in that: The invention comprises a low-pressure compressor (1), an intercooler (2), a first three-way valve (3), a high-pressure compressor (4), a first heat exchanger (5), an ejector (6), a second three-way valve (7), a first four-way reversing valve (8), a second four-way reversing valve (9), a second heat exchanger (10), a throttle valve (11), a third heat exchanger (12) and a third three-way valve (13), wherein the connection structure on the refrigerant side between the components is as follows: The outlet of the low-pressure compressor (1) and the inlet of the intermediate cooler (2), the outlet of the intermediate cooler (2) and the inlet of the first three-way valve (3), the first outlet of the first three-way valve (3) and the inlet of the high-pressure compressor (4), the outlet of the high-pressure compressor (4) and the refrigerant side inlet of the first heat exchanger (5), and the refrigerant side outlet of the first heat exchanger (5) and the first inlet of the ejector (6) are sequentially connected in series; The first end of the third three-way valve (13) is connected in series with the third heat exchanger (12), the throttle valve (11), the second heat exchanger (10) and the first end of the second three-way valve (7); The four interfaces of the first four-way reversing valve (8) are respectively connected to the inlet of the low-pressure compressor (1), the second outlet of the first three-way valve (3), the second end of the second three-way valve (7), and the second end of the third three-way valve (13); The four interfaces of the second four-way reversing valve (9) are respectively connected to the second inlet of the injector (6), the outlet of the injector (6), the third end of the second three-way valve (7) and the third end of the third three-way valve (13).

2. The heating, cooling and hot water supply system based on the two-stage injection compression cycle according to claim 1 is characterized in that: The heat exchange medium side of the first heat exchanger (5) is connected to the user's domestic water circulation pipeline.

3. The heating, cooling and hot water supply system based on the two-stage injection compression cycle according to claim 1 is characterized in that: The heat exchange medium side of the second heat exchanger (10) is connected to the user's air conditioning water circulation pipeline.

4. The heating, cooling and hot water supply system based on the two-stage injection compression cycle according to claim 1 is characterized in that: The heat exchange medium side of the third heat exchanger (12) is outdoor air.

5. An operating method for a heating, cooling and hot water supply system based on a two-stage injection compression cycle as claimed in claim 1, characterized in that: By adjusting the first four-way reversing valve (8) and the second four-way reversing valve (9), switching between the winter operation mode and the summer operation mode is achieved. In the winter operation mode, the domestic hot water and indoor heating needs are met, and in the summer operation mode, the domestic hot water and indoor cooling needs are met.

6. The method for operating a heating, cooling and hot water supply system based on a two-stage injection compression cycle according to claim 5, characterized in that: In the winter operation mode, the outlet of the ejector (6) is connected to the third end of the second three-way valve (7) through the second four-way reversing valve (9), and the third end of the third three-way valve (13) is connected to the second inlet of the ejector (6). The second outlet of the first three-way valve (3) is connected to the second end of the second three-way valve (7) through the first four-way reversing valve (8), and the second end of the third three-way valve (13) is connected to the inlet of the low-pressure compressor (1). The low-pressure compressor (1) and the high-pressure compressor (4) compress the refrigerant to a high-temperature and high-pressure state. The refrigerant in the first heat exchanger (5) is condensed on the heat exchange medium side to produce high-temperature domestic hot water. The ejector (6) is used to increase the pressure of part of the refrigerant in the third heat exchanger (12) to the pressure in the second heat exchanger (10), and the refrigerant is mixed with part of the medium-pressure refrigerant from the low-pressure compressor (1), condensed in the second heat exchanger (10), and formed into medium-temperature hot water on the heat exchange medium side for indoor low-temperature heating.

7. The method for operating a heating, cooling and hot water supply system based on a two-stage injection compression cycle according to claim 5, characterized in that: In the summer operation mode, the second outlet of the first three-way valve (3) is connected to the second end of the third three-way valve (13) through the first four-way reversing valve (8), and the second end of the second three-way valve (7) is connected to the inlet of the low-pressure stage compressor (1). The third end of the third three-way valve (13) is connected to the outlet of the ejector (6) through the second four-way reversing valve (9), and the second inlet of the ejector (6) is connected to the third end of the second three-way valve (7). The low-pressure stage compressor (1) and the high-pressure stage compressor (4) compress the refrigerant to a high-temperature and high-pressure state. The refrigerant in the first heat exchanger (5) is condensed to produce high-temperature domestic hot water on the heat exchange medium side, the refrigerant pressure in the second heat exchanger (10) is increased to the pressure in the third heat exchanger (12) by using an ejector (6), and is mixed with part of the refrigerant from the low-pressure compressor (1), and condensed in the third heat exchanger (12), and then the refrigerant is throttled to a low-temperature and low-pressure state by using a throttle valve (11), evaporated in the second heat exchanger (10), and low-temperature chilled water is produced on the heat exchange medium side for indoor cooling.

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