CN114279107B - An open heat pump power storage system and method - Google Patents

Abstract

The invention relates to the field of energy storage technology, and provides an open heat pump power storage system and method. The system includes a heat pump refrigeration and heating circuit; a cold and heat energy heat engine power generation circuit; When the heating circuit is heating, the excess air in the heating circuit is discharged to the external environment to reduce the air pressure in the heating circuit; among them, the heat pump cooling and heating circuit uses air as the working medium for heat exchange. The open heat pump electricity storage system provided by the present invention adopts air as the flowing working medium for heat transfer, and has lower cost than using argon, helium, etc. as the flowing working medium. Moreover, since the working fluid is air, the gas quality and pressure in the system can be directly adjusted through the venting structure connected with the external environment. While canceling the buffer tank, the airtightness requirements of the system as a whole are reduced, and the technology is improved. Feasibility, reducing the difficulty of research and development.

Description

An open heat pump power storage system and method

technical field

The invention relates to the technical field of energy storage, in particular to an open heat pump power storage system and method.

Background technique

At present, argon, helium, etc. are used as the working fluid in the heat pump power storage system of the Brayton cycle that uses the packed bed as the cold storage heat accumulator. In order to prevent the leakage of the gas working fluid, the whole system adopts a closed loop structure. During the storage and discharge process, the temperature change of the gas working medium will cause a large change in the gas density. Therefore, in a large-capacity packed bed with stable pressure and solid volume, the mass of stored gas will change periodically during storage and release. In order to maintain the quality and pressure balance of the working medium in the closed system, it is usually necessary to set up a buffer tank in the system. When the air pressure in the closed system is high, the excess gas can be discharged into the buffer tank. When the closed system When the air pressure in the tank is small, the gas in the buffer tank can be pumped into the system.

However, such a heat pump power storage system has strict requirements on airtightness, and the cost of using argon, helium, etc. as the working fluid is relatively high.

Contents of the invention

Therefore, the technical problem to be solved by the present invention is that the heat pump power storage system in the prior art has strict requirements on airtightness, and the cost of using argon, helium, etc. An open heat pump power storage system and method.

In order to solve the problems of the technologies described above, the technical solution of the present invention is as follows:

An open heat pump power storage system, including a heat pump refrigeration and heating circuit, suitable for converting excess electric energy into heat and cold energy during low power consumption; The heat energy and cold energy are converted into electric energy; it also includes: an air release structure, which is suitable for discharging excess air in the heating circuit to the external environment when the heat pump cooling and heating circuit is heating, so as to reduce the The air pressure in the heating circuit; wherein, the air inlet end and the air outlet end of the heat pump cooling and heating circuit are connected with the external environment; when the heat pump cooling and heating circuit converts excess electric energy into heat energy and cold energy, Air is used as the working medium for heat transfer.

Further, the heat pump refrigeration and heating circuit includes a drive unit, a multi-stage energy storage compressor, a high-temperature packed bed, a three-way valve A, a multi-stage energy storage expander, a low-temperature packed bed, and a three-way valve C; wherein, the The drive unit is connected to the multi-stage energy storage compressor and the multi-stage energy storage expander; the air inlet of the multi-stage energy storage compressor is connected to the external environment, and the multi-stage energy storage compressor The gas outlet of the high-temperature packed bed is connected to the gas inlet of the high-temperature packed bed, the first gas outlet of the high-temperature packed bed is connected to the gas inlet of the multi-stage energy storage expander, and the outlet of the multi-stage energy storage expander The gas port is connected to the first air inlet of the low-temperature packed bed, and the first gas outlet of the low-temperature packed bed is connected to the external environment; wherein, the three-way valve A is suitable for communicating with the multi-stage energy storage expander The air inlet of the high-temperature packed bed, the first gas outlet of the high-temperature packed bed, and the power generation circuit of the cold-heat energy heat engine; wherein, the three-way valve C is suitable for communicating with the external environment, the first gas outlet of the low-temperature packed bed, and The cold and heat energy heat engine power generation circuit; wherein, the air release structure is arranged on the pipeline between the three-way valve A and the multi-stage energy storage expander.

Further, the deflation structure includes a three-way valve B and a flow control valve; wherein, the three-way valve B is suitable for communicating with the air inlet of the multi-stage energy storage expander, the three-way valve A and the One end of the flow control valve, the other end of the flow control valve communicates with the external environment.

Further, a waste heat dissipation heat exchanger is arranged between the three-way valve A and the high-temperature packed bed, which is suitable for adjusting the air flowing out from the first air outlet of the high-temperature packed bed to room temperature.

Further, the open heat pump power storage system also includes a first dehumidification device, the air inlet of the first dehumidification device communicates with the external environment, and the air outlet of the first dehumidification device is connected to the multi-stage energy storage compression connected to the air inlet of the machine.

Further, the cold-heat energy heat engine power generation circuit includes a power generation unit, a multi-stage energy-releasing compressor, and a multi-stage energy-releasing expander; wherein, the power generating unit is connected to the multi-stage energy-releasing expander and the multi-stage energy-releasing expander The energy-releasing compressors are all connected; the air inlet of the multi-stage energy-releasing expander is connected with the second gas outlet of the high-temperature packed bed, and the gas outlet of the multi-stage energy-releasing expander is connected with the external environment; The second gas outlet of the low-temperature packed bed is connected to the air inlet of the multi-stage energy releasing compressor; wherein, the three-way valve A is suitable for communicating with the air inlet of the multi-stage energy storage expander, the The first gas outlet of the high-temperature packed bed and the gas outlet of the multi-stage energy-releasing compressor; wherein, one of the ports of the three-way valve C is connected to the first gas outlet of the low-temperature packed bed, and the other two ports They are all connected with the external environment; among them, when the thermal energy and cold energy are converted into electric energy by using the cold and heat energy heat engine power generation circuit, air is used as the flowing working medium for heat transfer.

Further, the open-type heat pump power storage system also includes an air supply structure, which is arranged on the pipeline between the three-way valve A and the multi-stage energy-releasing compressor, and is suitable for transferring heat energy When the cold energy is converted into electric energy, the air in the external environment is sent into the heat release circuit to increase the air pressure in the heat release circuit.

Further, the air supply structure includes a three-way valve D and a pump body; wherein, the three-way valve D is suitable for communicating with the air outlet of the multi-stage energy release compressor, the three-way valve A and the pump The air outlet of the pump body, and the air inlet of the pump body communicates with the external environment.

Further, the open heat pump power storage system also includes a second dehumidification device, the air inlet of the second dehumidification device communicates with the external environment, and the air outlet of the second dehumidification device is connected to the air inlet of the pump body. The ports are connected and are suitable for dehumidifying the air entering the pump body.

The present invention also provides an open heat pump electricity storage method, which at least includes the following steps: using a heat pump refrigeration and heating circuit to convert excess electric energy into heat energy and cold energy; It is electric energy; the inlet end and the air outlet end of the heat pump cooling and heating circuit are connected with the external environment, so that when the heat pump cooling and heating circuit converts excess electric energy into heat energy and cold energy, air is used as the flow tool The outside air enters the heat pump cooling and heating circuit for heat transfer and then is discharged to the external environment; wherein, when the heat pump cooling and heating circuit is heating, the air in the heating circuit is discharged through the air release structure. The excess air is exhausted to the external environment to reduce the air pressure in the heating circuit.

Further, before the air in the external environment is sent into the air intake end of the heat pump cooling and heating circuit, the first dehumidification device is used to dehumidify the air.

Further, when the thermal energy and cold energy are converted into electrical energy by using the cold-heat energy heat engine power generation circuit, air is used as the flowing working medium for heat transfer, and the external air is discharged to the The external environment; wherein, when the cold-heat energy heat engine power generation circuit releases heat, the air in the external environment is sent into the heat release circuit through the air supply structure, so as to increase the air pressure in the heat release circuit.

Furthermore, before the air in the external environment is sent into the heat release circuit by using the air supply structure, the air is dehumidified by the second dehumidification device.

Further, before the outside air enters the decooling circuit in the power generation circuit of the cold-heat energy heat engine, a third dehumidification device is used to dehumidify the air.

The technical solution of the present invention has the following advantages:

The open heat pump electricity storage system provided by the present invention adopts air as the flow working medium for heat transfer, and the cost is lower than that of using argon, helium, etc. as the flow working medium. Moreover, since the working medium is air, the gas quality and pressure in the system can be directly adjusted through the venting structure connected with the external environment. While canceling the buffer tank, the requirements for airtightness of the system as a whole are reduced, and the technology is improved. Feasibility, reducing the difficulty of research and development.

Description of drawings

In order to more clearly illustrate the specific implementation of the present invention or the technical solutions in the prior art, the following will briefly introduce the accompanying drawings that need to be used in the specific implementation or description of the prior art. Obviously, the accompanying drawings in the following description The drawings show some implementations of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative work.

Fig. 1 is a schematic structural diagram of an open heat pump power storage system in an embodiment of the present invention.

Explanation of reference signs:

1. First dehumidification device; 2. Drive unit; 3. First-stage energy storage compressor; 4. Second-stage energy storage compressor; 5. High-temperature packed bed; 6. Waste heat dissipation heat exchanger; 7. Tee Valve A; 8. Three-way valve B; 9. Flow control valve; 10. First-stage energy storage expander; 11. Second-stage energy storage expander; 12. Low-temperature packed bed; 13. Three-way valve C; 14 , the second dehumidification device; 15, the first stage energy release compressor; 16, the second stage energy release compressor; 17, the three-way valve D; 18, the third dehumidification device; 19, the pump body; 20, the first stage Energy-releasing expander; 21. Second-stage energy-releasing expander; 22. Power generation unit; 101. Pipeline A; 102. Pipeline B; 103. Pipeline C; 104. Pipeline D; 105. Pipeline E; 106, pipeline F; 107, pipeline G; 108, pipeline H; 109, pipeline I; 110, pipeline J; 111, pipeline K; 112, pipeline L; 113, pipeline M; 114, Pipeline N; 115, pipeline O; 116, pipeline P; 117, pipeline Q; 118, pipeline R; 119, pipeline S; 120, pipeline T; 121, pipeline U; 122, pipeline V; 123, pipeline W.

Detailed ways

The technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, or in a specific orientation. construction and operation, therefore, should not be construed as limiting the invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and should not be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary, and it may be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as there is no conflict with each other.

Fig. 1 is a schematic structural diagram of an open heat pump power storage system in an embodiment of the present invention. As shown in Fig. 1, this embodiment provides an open heat pump power storage system, including a heat pump cooling and heating circuit, suitable for Convert excess electrical energy into heat and cold energy during low valleys; cold and heat heat engine power generation circuit, suitable for converting heat and cold energy into electrical energy during peak power consumption; also includes: air release structure, suitable for cooling and heating in heat pumps When the circuit is heating, the excess air in the heating circuit is discharged to the external environment to reduce the air pressure in the heating circuit; among them, the inlet and outlet ends of the heat pump cooling and heating circuit are connected to the external environment ; When the heat pump refrigeration and heating circuit converts excess electric energy into heat energy and cold energy, air is used as the flowing working medium for heat transfer.

The open heat pump electricity storage system provided by the present invention adopts air as the flow working medium for heat transfer, and the cost is lower than that of using argon, helium, etc. as the flow working medium. Moreover, since the working medium is air, the gas quality and pressure in the system can be directly adjusted through the venting structure connected with the external environment. While canceling the buffer tank, the requirements for airtightness of the system as a whole are reduced, and the technology is improved. Feasibility, reducing the difficulty of research and development.

Among them, the heat pump cooling and heating circuit includes a drive unit 2, a multi-stage energy storage compressor, a high-temperature packed bed 5, a three-way valve A7, a multi-stage energy storage expander, a low-temperature packed bed 12, and a three-way valve C13; 2 connected to the multi-stage energy storage compressor and the multi-stage energy storage expander; the inlet of the multi-stage energy storage compressor is connected to the external environment, and the gas outlet of the multi-stage energy storage compressor is connected to the The air inlets are connected, the first air outlet of the high-temperature packed bed 5 is connected with the air inlet of the multi-stage energy storage expander, the air outlet of the multi-stage energy storage expander is connected with the first air inlet of the low-temperature packed bed 12, and the low-temperature The first gas outlet of the packed bed 12 is connected with the external environment; wherein, the three-way valve A7 is suitable for connecting the inlet of the multi-stage energy storage expander, the first gas outlet of the high-temperature packed bed 5, and the power generation circuit of the cold and heat energy heat engine ; Wherein, the three-way valve C13 is suitable for communicating with the external environment, the first gas outlet of the low-temperature packed bed 12, and the power generation circuit of the cold and heat energy heat engine; wherein, the deflation structure is arranged between the three-way valve A7 and the multi-stage energy storage expander on the pipeline.

Among them, the deflation structure includes a three-way valve B8 and a flow control valve 9; wherein, the three-way valve B8 is suitable for connecting the air inlet of the multi-stage energy storage expander, the three-way valve A7 and one end of the flow control valve 9, and the flow control The other end of the valve 9 communicates with the external environment.

Wherein, a waste heat dissipation heat exchanger 6 is arranged between the three-way valve A7 and the high-temperature packed bed 5, which is suitable for adjusting the air flowing out from the first air outlet of the high-temperature packed bed 5 to room temperature.

Wherein, the open heat pump power storage system also includes a first dehumidification device 1, the air inlet of the first dehumidification device 1 is connected with the external environment, and the air outlet of the first dehumidification device 1 is connected with the air inlet of the multi-stage energy storage compressor. The mouth is connected.

Wherein, the power generation circuit of the cold and heat energy heat engine includes a power generation unit 22, a multi-stage energy-releasing compressor, and a multi-stage energy-releasing expander; wherein, the generating unit 22 is connected with the multi-stage energy-releasing expander and the multi-stage energy-releasing compressor; The air inlet of the multistage energy release expander is connected with the second gas outlet of the high temperature packed bed 5, and the gas outlet of the multistage energy release expander is connected with the external environment; the second gas outlet of the low temperature packed bed 12 is connected with the multistage release The air inlet of the energy compressor is connected; wherein, the three-way valve A7 is suitable for connecting the air inlet of the multi-stage energy storage expander, the first air outlet of the high-temperature packed bed 5, and the air outlet of the multi-stage energy release compressor; wherein , one of the interfaces of the three-way valve C13 is connected to the first gas outlet of the low-temperature packed bed 12, and the other two interfaces are connected to the external environment; wherein, when the heat and cold energy are converted into electric energy by using the cold and heat energy heat engine power generation circuit , using air as the working medium for heat transfer.

Among them, the open heat pump power storage system also includes an air supply structure, which is arranged on the pipeline between the three-way valve A7 and the multi-stage energy release compressor, which is suitable for converting heat energy and cold energy into When using electric energy, the air in the external environment is sent into the heat release circuit to increase the air pressure in the heat release circuit.

Wherein, the gas supply structure includes a three-way valve D17 and a pump body 19; wherein, the three-way valve D17 is suitable for connecting the air outlet of the multi-stage energy release compressor, the three-way valve A7 and the air outlet of the pump body 19, and the outlet of the pump body 19 The air inlet communicates with the external environment.

Wherein, the open heat pump power storage system further includes a second dehumidification device 14, the air inlet of the second dehumidification device 14 is connected with the external environment, and the air outlet of the second dehumidification device 14 is connected with the air inlet of the pump body 19, Suitable for dehumidifying the air entering the pump body 19 .

In the following description, the multi-stage energy storage compressor, multi-stage energy storage expander, multi-stage energy release compressor and multi-stage energy release expander are all two-stage examples for illustration:

Among them, the pipelines used to connect various parts, as shown in Figure 1, the pipeline A101 is suitable for connecting the external environment and the first stage energy storage compressor 3, and the pipeline B102 is suitable for connecting the first dehumidification device 1 and the first stage Energy storage compressor, the pipeline C103 is suitable for connecting the first-stage energy storage compressor 3 and the second-stage energy storage compressor 4, and the pipeline D104 is suitable for connecting the second-stage energy storage compressor 4 and the high-temperature packed bed 5. The road E105 is suitable for communicating with the high-temperature packed bed 5 and the waste heat dissipation heat exchanger 6 . The pipeline F106 is suitable for connecting the waste heat dissipation heat exchanger 6 and the three-way valve A7, the pipeline G107 is suitable for connecting the three-way valve A7 and the three-way valve B8, and the pipeline H108 is suitable for connecting the three-way valve B8 and the first stage storage For the energy expander 10 , the pipeline I109 is suitable for connecting the first-stage energy storage expander 10 and the second-stage energy storage expander 11 , and the pipeline J110 is suitable for connecting the second-stage energy storage expander 11 and the low-temperature packed bed 12 . The pipeline K111 is suitable for connecting the low-temperature packed bed 12 and the three-way valve C13, the pipeline L112 is suitable for connecting the three-way valve C13 and the external environment, the pipeline M113 is suitable for connecting the external environment and the third dehumidification device 18, and the pipeline N114 is suitable for The three-way valve C13 is connected with the third dehumidification device 18 , and the pipeline O115 is suitable for connecting the low-temperature packed bed 12 with the first-stage energy-releasing compressor 15 . Pipeline P116 is suitable for communicating with the first-stage energy-discharging compressor 15 and the second-stage energy-discharging compressor 16, pipeline Q117 is suitable for communicating with the second-stage energy-discharging compressor 16 and the three-way valve D17, and pipeline R118 is suitable for communicating with The second dehumidification device 14 is connected to the pump body 19, the pipeline S119 is suitable for connecting the pump body 19 and the three-way valve D17, and the pipeline T120 is suitable for connecting the three-way valve D17 and the three-way valve A7. The pipeline U121 is suitable for connecting the high-temperature packed bed 5 with the first-stage energy-releasing expander 20, the pipeline V122 is suitable for connecting the first-stage energy-releasing expander 20 and the second-stage energy-releasing expander 21, and the pipeline W123 is suitable for communicating with The second stage energy release expander 21 and the external environment.

Wherein, the flow control valve 9 is used to adjust the deflation speed of the deflation structure.

Wherein, the positional relationship between the pump body 19 and the second dehumidification device 14 is adjustable, the air can pass through the pump body 19 first, and then pass through the second dehumidification device 14, and the air can also pass through the second dehumidification device 14 first, and then pass through the pump body 19.

Another embodiment also provides an open heat pump electricity storage method, which at least includes the following steps: using a heat pump cooling and heating circuit to convert excess electric energy into heat energy and cold energy; Converted into electrical energy; the inlet and outlet ends of the heat pump cooling and heating circuit are connected with the external environment, so that when the heat pump cooling and heating circuit converts excess electric energy into heat and cold energy, air is used as the flowing working medium for transmission. The outside air enters the heat pump cooling and heating circuit to transfer heat and then is discharged to the external environment; among them, when the heat pump cooling and heating circuit is heating, the excess air in the heating circuit is discharged to the external environment through the deflation structure to reduce the air pressure in the heating circuit.

Wherein, before the air in the external environment is sent into the air intake end of the heat pump cooling and heating circuit, the first dehumidification device 1 is used to dehumidify the air.

Among them, when using the cold heat energy heat engine power generation circuit to convert heat energy and cold energy into electric energy, air is used as the flowing working medium for heat transfer, and the external air is discharged to the external environment after heat transfer through the cold heat energy heat engine power generation circuit; among them, When the cold-heat energy heat engine power generation circuit releases heat, the air in the external environment is sent into the heat release circuit through the air supply structure, so as to increase the air pressure in the heat release circuit.

Wherein, the second dehumidification device 14 is used to dehumidify the air before the air in the external environment is sent into the heat release circuit by the air supply structure.

Wherein, the third dehumidification device 18 is used to dehumidify the air before the outside air enters the cooling circuit in the power generation circuit of the cold and heat energy heat engine.

The specific operation process of the open heat pump power storage system is as follows:

When the power consumption is low, the heat pump cooling and heating circuit is started to convert the electric energy into cold and heat energy for storage.

The first-stage energy storage compressor 3, the second-stage energy storage compressor 4, the first-stage energy storage expander 10, and the second-stage energy storage expander 11 are connected in transmission, and the drive unit 2 and the first-stage energy storage compressor 3 Driver connection. Controlling the three-way valve A7 makes the pipeline F106 communicate with the pipeline G107; controlling the three-way valve C13 makes the pipeline K111 communicate with the pipeline L112. The three-way of the three-way valve B8 is normally open.

Air at room temperature and pressure is extracted from the external environment, and dried air is obtained after being dehumidified by the first dehumidification device 1 . Dry air at normal temperature and pressure sequentially flows through the first-stage energy storage compressor 3, the pipeline C103, and the second-stage energy storage compressor 4 to be compressed to a high-temperature, medium/high-pressure state, and then flows into the high-temperature packed bed 5 along the pipeline D104 and The solid particle heat storage material in it performs heat exchange and stores thermal energy in it.

Due to the unsteady state of the system, the temperature of the normal temperature and medium/high pressure gas working fluid flowing out of the high temperature packed bed 5 may not be completely lowered to room temperature, so a waste heat dissipation heat exchanger 6 is installed, and the gas working fluid flows into the waste heat along the pipeline E105 The heat dissipation heat exchanger 6 dissipates the waste heat to the environment. Subsequently, the gas working medium at room temperature and medium/high pressure flows into the inlet of the energy storage expander along the pipeline F106, pipeline G107, and pipeline H108, and then passes through the first-stage energy storage expander 10, pipeline I109, and second-stage energy storage The expander 11 expands to a state of low temperature and normal pressure. The low-temperature and normal-pressure gas working fluid flows into the low-temperature packed bed 12 along the pipeline J110, exchanges heat with the solid heat-storage working medium therein, and stores cold energy therein.

The normal-temperature and normal-pressure gas working fluid flowing out of the low-temperature packed bed 12 is directly discharged into the environment along the pipeline K111 and the pipeline L112. Continuously extract air from the environment, compress and expand, and so on, and continuously convert electric energy into cold energy and heat energy for storage. As the energy storage process proceeds, the temperature of the gas in the high-temperature packed bed 5 increases and the density decreases; the temperature of the gas in the low-temperature packed bed 12 decreases and the density increases. In order to maintain the internal mass conservation and pressure stability of the system, the opening of the flow control valve 9 is adjusted to exhaust to the environment.

During the peak period of electricity consumption, the cold and heat energy heat engine power generation circuit is started to convert the stored high-grade heat and cold energy into electric energy for release.

Control the three-way valve A7 to make the pipeline F106 communicate with the pipeline T120; control the three-way valve C13 to connect the pipeline K111 and the pipeline N114; the three channels of the three-way valve D17 are normally open. Air at room temperature and pressure flows into the third dehumidification device 18 along the pipeline M113 for dehumidification to obtain dry air. The dry air at room temperature and pressure enters the low-temperature packed bed 12 along the pipeline N114 and pipeline K111 to absorb the cold energy therein to a state of low temperature and normal pressure.

The low-temperature and normal-pressure gas working medium flows out of the low-temperature packed bed 12, flows into the inlet of the energy-releasing compressor along the pipeline O115, and is sequentially compressed by the first-stage energy-releasing compressor 15, the pipeline P116, and the second-stage energy-releasing compressor 16 To room temperature, medium/high pressure. The normal temperature, medium/high pressure gas working fluid passes through the pipeline Q117, pipeline T120 and pipeline F106, and after the waste heat is discharged to the environment through the waste heat heat exchanger 6, the room temperature, medium/high pressure gas working medium flows along the pipeline E105 enters the high-temperature packed bed 5 to absorb high-temperature heat energy to a high-temperature, medium/high-pressure state.

High-temperature, medium/high-pressure gas working fluid flows into the inlet of the energy-releasing expander along the pipeline U121. Sequentially go through the first-stage energy-releasing expander 20, pipeline V122, and second-stage energy-releasing expander 21 to expand to normal temperature and normal pressure. Then the gaseous working medium is discharged into the environment along the pipeline W123.

The first-stage energy-releasing compressor 15 , the second-stage energy-releasing compressor 16 , the first-stage energy-releasing expander 20 , and the second-stage energy-releasing expander 21 are in transmission connection, and the energy-releasing expander is drivingly connected to the power generation unit 22 .

Continuously extract air from the environment, dry it and enter the low-temperature packed bed 12 to absorb cold energy, compress it, enter the high-temperature packed bed 5 to absorb heat, and expand to do work. Repeat this process to continuously convert cold energy and heat energy into electrical energy and release it. During the energy release process, the temperature in the high-temperature packed bed 5 gradually decreases, and the temperature in the low-temperature packed bed 12 gradually increases. In order to maintain the mass conservation and pressure stability of the working fluid in the system, turn on the pressure regulating compressor and pump gas into the system. Note that the air must be dehumidified to dry air by the dehumidification device in the pressure regulating pipeline before use.

Among them, for the choice of working fluid, the flowing working fluid in the system is all air.

Among them, the selection of power equipment:

The driving unit 2 is a driving motor or an electric motor. When the driving unit 2 is a driving motor, one or more of conventional power station low power, nuclear power, wind power, solar power, hydropower or tidal power is used as the power source.

Multi-stage energy storage compressors and multi-stage energy release compressors, the total pressure ratio is between 3-20; when the compressors are multiple compressors, the multiple compressors are in the form of coaxial series or split shaft parallel. In the parallel mode, each branch shaft is dynamically connected with the main drive shaft.

The energy storage expander and the energy release expander, the total expansion ratio is between 3-20; when the expander is multiple expanders, the multiple expanders are in the form of coaxial series or split shaft parallel; in the parallel form, Each branch shaft is dynamically connected with the main drive shaft.

The multi-stage energy storage compressor, multi-stage energy storage expander, multi-stage energy release compressor and multi-stage energy release expander shown in Fig. 1 are all drawn with two stages, but actually the number of stages can be 2-6.

For storage devices:

The high-temperature packed bed 5 and the low-temperature packed bed 12 are cylinders, spheres or cuboids, and the solid cold and heat storage medium is one or a combination of at least two materials such as rocks, sand, metal particles, and solid bricks.

Wherein, the first dehumidification device 1 , the second dehumidification device 14 and the third dehumidification device 18 may all be dehumidifiers.

In summary, the open heat pump power storage system provided by the present invention can still realize the structure and control scheme of working fluid mass balance and pressure stability without using a buffer tank; the system as a whole adopts an open structure design, and uses easily obtained air as Flowing working medium reduces the cost and strict requirements on the airtightness of the system; compared with the technology of helium compressor/expander and argon compressor/expander, the technology of air compressor/expander is relatively mature, and it also improves the technology Feasibility, reducing the difficulty of research and development.

Apparently, the above-mentioned embodiments are only examples for clear description, rather than limiting the implementation. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. It is not necessary and impossible to exhaustively list all the implementation manners here. And the obvious changes or changes derived therefrom are still within the scope of protection of the present invention.

Claims (9)

1. An open heat pump electricity storage system comprises a heat pump refrigerating and heating loop, a heat pump and a heat pump, wherein the heat pump refrigerating and heating loop is suitable for converting redundant electric energy into heat energy and cold energy during electricity consumption valley; the cold and heat energy heat engine power generation loop is suitable for converting the heat energy and the cold energy into electric energy at the peak of power utilization;

it is characterized by also comprising: the air discharging structure is suitable for discharging redundant air in the heating loop to the external environment when the heat pump refrigerating and heating loop heats so as to reduce the air pressure in the heating loop;

the air inlet end and the air outlet end of the heat pump refrigerating and heating loop are both communicated with the external environment; when the heat pump refrigerating and heating loop converts redundant electric energy into heat energy and cold energy, air is used as a flowing working medium for heat transfer;

the heat pump refrigerating and heating loop comprises a driving unit, a multistage energy storage compressor, a high-temperature packed bed, a three-way valve A, a multistage energy storage expander, a low-temperature packed bed and a three-way valve C;

the driving unit is connected with the multistage energy storage compressor and the multistage energy storage expander;

the air inlet of the multistage energy storage compressor is communicated with the external environment, the air outlet of the multistage energy storage compressor is connected with the air inlet of the high-temperature packed bed, the first air outlet of the high-temperature packed bed is connected with the air inlet of the multistage energy storage expander, the air outlet of the multistage energy storage expander is connected with the first air inlet of the low-temperature packed bed, and the first air outlet of the low-temperature packed bed is communicated with the external environment;

the three-way valve A is suitable for being communicated with a gas inlet of the multistage energy storage expansion machine, a first gas outlet of the high-temperature packed bed and the cold-heat energy heat engine power generation loop;

the three-way valve C is suitable for being communicated with the external environment, a first air outlet of the low-temperature packed bed and the cold-heat energy heat engine power generation loop;

the air bleeding structure is arranged on a pipeline between the three-way valve A and the multi-stage energy storage expansion machine;

the air discharging structure comprises a three-way valve B and a flow control valve; the three-way valve B is suitable for being communicated with an air inlet of the multistage energy storage expansion machine, the three-way valve A and one end of the flow control valve, and the other end of the flow control valve is communicated with the external environment;

the cold and heat energy heat engine power generation loop comprises a power generation unit, a multi-stage energy release compressor and a multi-stage energy release expander;

the power generation unit is connected with the multi-stage energy release expander and the multi-stage energy release compressor;

the air inlet of the multi-stage energy release expansion machine is connected with the second air outlet of the high-temperature packed bed, and the air outlet of the multi-stage energy release expansion machine is communicated with the external environment;

a second air outlet of the low-temperature packed bed is connected with an air inlet of the multi-stage energy release compressor;

the three-way valve A is suitable for being communicated with a gas inlet of the multistage energy storage expansion machine, a first gas outlet of the high-temperature packed bed and a gas outlet of the multistage energy release compressor;

one interface of the three-way valve C is connected with a first air outlet of the low-temperature packed bed, and the other two interfaces are communicated with the external environment;

when the cold and heat energy is converted into electric energy by using the cold and heat energy heat engine power generation loop, air is used as a flowing working medium for heat transfer;

the air supplementing structure is arranged on a pipeline between the three-way valve A and the multi-stage energy release compressor and is suitable for sending air in the external environment into the heat release loop to increase the air pressure in the heat release loop when the cold and hot energy heat engine power generation loop converts heat energy and cold energy into electric energy;

the air supplementing structure comprises a three-way valve D and a pump body; the three-way valve D is suitable for being communicated with an air outlet of the multistage energy-releasing compressor, the three-way valve A and an air outlet of the pump body, and an air inlet of the pump body is communicated with the external environment.

2. The open heat pump electric storage system of claim 1,

and a waste heat dissipation heat exchanger is arranged between the three-way valve A and the high-temperature packed bed and is suitable for adjusting the air flowing out of the first air outlet of the high-temperature packed bed to room temperature.

3. The open heat pump electric storage system of claim 1,

the air inlet of the first dehumidifying device is communicated with the external environment, and the air outlet of the first dehumidifying device is connected with the air inlet of the multistage energy storage compressor.

4. The open heat pump electric storage system of claim 1,

the air inlet of the second dehumidifying device is communicated with the external environment, and the air outlet of the second dehumidifying device is connected with the air inlet of the pump body and is suitable for dehumidifying the air entering the pump body.

5. An open heat pump electricity storage method comprising the open heat pump electricity storage system of any one of claims 1-4, comprising at least the steps of:

the redundant electric energy is converted into heat energy and cold energy by utilizing a heat pump refrigerating and heating loop;

converting the heat energy and the cold energy into electric energy by utilizing a cold and heat energy heat engine power generation loop;

the heat pump refrigerating and heating system is characterized in that an air inlet end and an air outlet end of the heat pump refrigerating and heating loop are both communicated with the external environment, so that when the heat pump refrigerating and heating loop converts redundant electric energy into heat energy and cold energy, air is used as a flowing working medium for heat transfer, and the external air enters the heat pump refrigerating and heating loop for heat transfer and then is discharged into the external environment;

when the heat pump refrigerating and heating loop heats, redundant air in the heating loop is discharged to the external environment through the air discharging structure, so that air pressure in the heating loop is reduced.

6. The open heat pump electricity storage method of claim 5,

before air in the external environment is sent to the air inlet end of the heat pump refrigerating and heating loop, a first dehumidifying device is adopted to dehumidify the air.

7. The open heat pump electricity storage method of claim 6,

when the heat energy and the cold energy are converted into electric energy by utilizing the cold and heat energy heat engine power generation loop, air is adopted as a flowing working medium for heat transfer, and outside air is discharged to the outside environment after being transferred by the cold and heat energy heat engine power generation loop;

when the cold and heat energy heat engine power generation loop releases heat, air in the external environment is sent into the heat release loop through the air supply structure, so that the air pressure in the heat release loop is increased.

8. The open heat pump electricity storage method of claim 7,

before air in the external environment is sent to the heat release loop by adopting the air supplementing structure, the air is dehumidified by adopting a second dehumidifying device.

9. The open heat pump electricity storage method of claim 7,

and before the outside air enters a cold release loop in the cold and heat energy heat engine power generation loop, a third dehumidification device is adopted to carry out dehumidification treatment on the air.

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