Heat pump energy storage system with fast start of discharge process and control method thereof

Abstract

This disclosure proposes a heat pump energy storage system and its control method for rapid start-up during discharge, relating to the field of energy storage technology. The system includes a heat exchange device for energy storage. After preheating the working fluid in the heat pump energy storage system using the heat exchange device, the working fluid is further heated by introducing a high-temperature heat storage tank and a regenerator. This disclosure utilizes additional heat exchange equipment to preheat the working fluid during the power generation process of the heat pump energy storage system, increasing the inlet temperature of the high-temperature expander during discharge, rapidly raising the system temperature, and significantly shortening the start-up time of the heat pump energy storage system. This improves the system's grid dispatch load response capability, provides stable output, and enhances the system's energy utilization efficiency.

Description

Technical Field

[0001] This disclosure relates to the field of energy storage technology, and in particular to a heat pump energy storage system and its control method that allows for rapid start-up during the discharge process. Background Technology

[0002] During the charging process, the heat pump energy storage system uses a heat pump cycle to convert electrical energy into heat energy and cold energy, and stores the energy through a high-temperature heat medium and / or a low-temperature cold medium, respectively. During the discharging process, the heat energy and cold energy stored during the charging process are converted into electrical energy through a heat engine cycle.

[0003] Heat pump energy storage systems contain numerous components, making the system startup process complex, especially during cold starts. This involves not only raising the system pressure to the required operating pressure but also preheating heat exchangers, storage tanks, and other related equipment to reduce thermal stress caused by rapid temperature increases during startup. This process is time-consuming. While peak-shaving systems typically require a response time of one hour, the lengthy cold start process of heat pump energy storage systems makes it difficult to meet these time constraints. Therefore, a rapid startup method for heat pump energy storage systems is urgently needed to achieve faster startup times. Summary of the Invention

[0004] This disclosure aims to at least partially address one of the technical problems in the related art.

[0005] Therefore, the first aspect of this disclosure proposes a heat pump energy storage system for rapid start-up during discharge, comprising: an electric motor, a cryogenic compressor, a regenerator, a heat exchange device, a cryogenic heat storage tank, a high-temperature heat storage tank, a cryogenic heat storage tank, a high-temperature expander, and a generator;

[0006] The electric motor is connected to the cryogenic compressor, the cryogenic compressor is coaxially connected to the high-temperature expander, the high-temperature expander is connected to the generator, the outlet of the cryogenic compressor is connected to the cold-side inlet of the regenerator, the cold-side outlet of the regenerator is connected to the cold-side inlet of the cryogenic heat storage tank through a first valve, the cold-side outlet of the regenerator is connected to the cold-side inlet of the cryogenic heat storage tank through a second valve and the heat exchange equipment, the hot-side inlet of the cryogenic heat storage tank is connected to the high-temperature heat storage tank, the hot-side outlet of the cryogenic heat storage tank is connected to the cryogenic heat storage tank, the cold-side outlet of the cryogenic heat storage tank is connected to the inlet of the high-temperature expander, the outlet of the high-temperature expander is connected to the hot-side inlet of the regenerator through a third valve, the outlet of the high-temperature expander is connected to the hot-side outlet of the regenerator through a fourth valve, and the hot-side outlet of the regenerator is connected to the inlet of the cryogenic compressor.

[0007] The temperature of the heat storage medium in the heat storage and exchange equipment is higher than a first temperature threshold.

[0008] In some embodiments of this disclosure, a cryogenic heat exchanger and a cooler are included between the hot-side outlet of the regenerator and the inlet of the cryogenic compressor; wherein, the hot-side outlet of the regenerator is connected to the hot-side inlet of the cooler, the hot-side outlet of the cooler is connected to the hot-side inlet of the cryogenic heat exchanger, the hot-side outlet of the cryogenic heat exchanger is connected to the inlet of the cryogenic compressor, the cold-side inlet of the cooler is connected to cooling water, the cold-side inlet of the cryogenic heat exchanger is connected to a cryogenic cold storage tank, and the cold-side outlet of the cryogenic heat exchanger is connected to a high-temperature cold storage tank.

[0009] In some embodiments of this disclosure, the heat storage and exchange equipment is any one of the following: a stacked bed, a fluidized bed, various types of heat storage equipment containing heat exchange tubes, and a combination of a heat storage medium container connected to a matching heat exchanger.

[0010] In some embodiments of this disclosure, the heat storage medium in the low-temperature heat storage tank and the high-temperature heat storage tank is any one of the following: molten salt, heat transfer oil, solid material, or phase change material.

[0011] In some embodiments of this disclosure, the cold storage medium in the low-temperature cold storage tank and the high-temperature cold storage tank is any one or more of the following: methanol, ethanol, ethylene glycol, calcium chloride aqueous solution; or, the cold storage medium is a phase change material.

[0012] A second aspect of this disclosure provides a control method applied to a heat pump energy storage system with rapid start-up during the discharge process as described in the first aspect above. The method includes the following steps:

[0013] In response to the heat pump energy storage system receiving a power generation command, the second valve and the fourth valve are opened, the first valve and the third valve are closed, and the outlet of the high-temperature heat storage tank is closed;

[0014] Once the outlet temperature of the cryogenic compressor reaches the second temperature threshold, the outlet of the high-temperature heat storage tank is opened.

[0015] Once the outlet temperature of the high-temperature expander reaches the second temperature threshold, the fourth valve is closed and the third valve is opened.

[0016] Once the temperature at the cold side outlet of the regenerator reaches the third temperature threshold, the first valve is opened and the second valve is closed.

[0017] A third aspect of this disclosure provides a control device, characterized in that the control device is applied to the heat pump energy storage system for rapid start-up during the discharge process described in the first aspect above, the device comprising:

[0018] The first control module is used to respond to the heat pump energy storage system receiving a power generation command by opening the second valve and the fourth valve, closing the first valve and the third valve, and closing the outlet of the high-temperature heat storage tank;

[0019] The second control module is used to determine when the outlet temperature of the cryogenic compressor reaches the second temperature threshold and to open the outlet of the high-temperature heat storage tank.

[0020] The third control module is used to determine when the outlet temperature of the high-temperature expander reaches the second temperature threshold, close the fourth valve, and open the third valve;

[0021] The fourth control module is used to determine that the temperature at the cold side outlet of the regenerator reaches the third temperature threshold, open the first valve, and close the second valve.

[0022] The control method for a heat pump energy storage system with rapid start-up during discharge provided in this disclosure utilizes additional heat exchange equipment to preheat the working fluid during the power generation process of the heat pump energy storage system. This increases the inlet temperature of the high-temperature expander during discharge, rapidly raising the system temperature and significantly shortening the start-up time of the heat pump energy storage system. While improving the system's grid dispatch load response capability and providing stable output, this method also enhances the system's energy utilization efficiency.

[0023] Additional aspects and advantages of this disclosure will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this disclosure. Attached Figure Description

[0024] The above and / or additional aspects and advantages of this disclosure will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, in which:

[0025] Figure 1 A schematic diagram of a heat pump energy storage system for rapid start-up during discharge, provided in an embodiment of this disclosure;

[0026] Figure 2 A schematic flowchart illustrating a control method for a heat pump energy storage system provided in an embodiment of this disclosure;

[0027] Figure 3 This is a schematic diagram of a control device for a heat pump energy storage system provided in an embodiment of the present disclosure. Detailed Implementation

[0028] Embodiments of this disclosure are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this disclosure, and should not be construed as limiting this disclosure.

[0029] Specifically, the following describes a heat pump energy storage system and its control method for rapid start-up during the discharge process according to embodiments of the present disclosure, with reference to the accompanying drawings.

[0030] Figure 1 This is a schematic diagram of a heat pump energy storage system for rapid start-up during the discharge process, provided as an embodiment of this disclosure. Figure 1 As shown, the heat pump energy storage system includes: an electric motor 1, a cryogenic compressor 2, a regenerator 7, a heat exchanger 8, a cryogenic heat storage tank 9, a high-temperature heat storage tank 10, a high-temperature heat exchanger 11, a high-temperature expander 12, and a generator 13.

[0031] In some embodiments of this disclosure, the heat storage and exchange device 8 can be any of the following: a stacked bed, a fluidized bed, various types of heat storage devices containing heat exchange tubes, and a combination of a heat storage medium container connected to a matching heat exchanger.

[0032] In some embodiments of this disclosure, the heat storage medium in the low-temperature heat storage tank 9 and the high-temperature heat storage tank 10 can be any of the following: molten salt, heat transfer oil, solid materials, or phase change materials. For example, potassium nitrate, calcium nitrate, sodium nitrate, sodium nitrite, lithium nitrate, mineral oil, heat transfer oil, liquid molten salt, etc.

[0033] In some embodiments of this disclosure, the circulating working fluid in the heat pump energy storage system can be air, argon, nitrogen, carbon dioxide, or other inert gases.

[0034] Electric motor 1 is connected to cryogenic compressor 2. Cryogenic compressor 2 is coaxially connected to high-temperature expander 12. High-temperature expander 12 is connected to generator 13. The outlet of cryogenic compressor 2 is connected to the cold-side inlet of regenerator 7. The cold-side outlet of regenerator 7 is connected to the cold-side inlet of high-temperature heat exchanger 11 through first valve 16. The hot-side outlet of regenerator 7 is connected to the cold-side inlet of high-temperature heat exchanger 11 through second valve 15 and heat storage / exchange device 8. The hot-side inlet of high-temperature heat exchanger 11 is connected to high-temperature heat storage tank 10. The hot-side outlet of high-temperature heat exchanger 11 is connected to cryogenic heat storage tank 9. The cold-side outlet of high-temperature heat exchanger 11 is connected to the inlet of high-temperature expander 12. The outlet of high-temperature expander 12 is connected to the hot-side inlet of regenerator 7 through third valve 18. The outlet of high-temperature expander 12 is connected to the hot-side outlet of regenerator 7 through fourth valve 17. The hot-side outlet of regenerator 7 is connected to the inlet of cryogenic compressor 2.

[0035] In this heat storage and heat exchange device 8, the temperature of the heat storage medium is higher than the first temperature threshold T0, ensuring that during the discharge process, the outlet temperature of the heat storage and heat exchange device 8 at the rated flow rate is not lower than the fourth temperature threshold T2. In one implementation, the heat storage and heat exchange device 8 can complete heat storage during the electricity storage process of the heat pump energy storage system. As an example, it can store new energy electricity during off-peak hours. In this example, since the heat of the heat storage and heat exchange device 8 originates from the compressor outlet during the heat storage process, and the heat source is the charging process that absorbs abandoned electricity, no additional heater is required in this disclosure, saving system operating costs, further improving the system's economic efficiency, and reducing energy waste.

[0036] The charging process of the heat pump energy storage system is a reverse Brayton cycle, utilizing electrical energy to store thermal and cold energy. An electric motor consumes electrical energy to drive a high-temperature compressor, compressing the gaseous circulating working fluid to a high-temperature, high-pressure state. The high-temperature, high-pressure gaseous circulating working fluid at the compressor outlet exchanges heat with the medium in the heat exchanger 8, then flows through the high-temperature heat exchanger; it exchanges heat with the heat storage medium in the heat storage system, lowering its temperature. The heat storage medium absorbs heat from the gaseous circulating working fluid and stores it in the heat storage system. Afterward, the cooled gaseous circulating working fluid enters the regenerator, releases heat, and then enters the low-temperature expander to cool and depressurize, becoming a low-temperature, low-pressure state. The low-temperature, low-pressure gaseous circulating working fluid enters the cold storage system, exchanging heat with the cold storage medium, which releases heat and stores it in the cold storage system. The low-temperature, low-pressure air further enters the regenerator, exchanges heat with the gaseous circulating working fluid on the hot side, and its temperature rises before finally entering the high-temperature compressor, completing the energy storage cycle.

[0037] The first temperature threshold T0, the second temperature threshold T1, the third temperature threshold T2, and the rated temperature T3 are set according to the following relationship: T3>T0>T2>T1. As an example, the following values ​​can be used (the values ​​are only illustrative): first temperature threshold T0 = 300℃, second temperature threshold T1 = 112℃, third temperature threshold T2 = 270℃, rated temperature T3 = 550℃.

[0038] It should be noted that, in some embodiments of this disclosure, the heat pump energy storage system further includes a cooling device between the hot-side outlet of the regenerator 7 and the inlet of the cryogenic compressor 2 to remove unrecoverable waste heat during system circulation. As an example, the heat pump energy storage system may also include a cooler 6, a cryogenic heat exchanger 3, a cryogenic cold storage tank 4, and a high-temperature cold storage tank 5. The hot-side outlet of the regenerator 7 and the inlet of the cryogenic compressor 2 are connected to the cryogenic heat exchanger 3 and the cooler 6. Specifically, the hot-side outlet of the regenerator 7 is connected to the hot-side inlet of the cooler 6, the hot-side outlet of the cooler 6 is connected to the hot-side inlet of the cryogenic heat exchanger 3, the hot-side outlet of the cryogenic heat exchanger 3 is connected to the inlet of the cryogenic compressor 2, the cold-side inlet of the cooler 6 is connected to cooling water, the cold-side inlet of the cryogenic heat exchanger 3 is connected to the cryogenic cold storage tank 4, and the cold-side outlet of the cryogenic heat exchanger 3 is connected to the high-temperature cold storage tank 5.

[0039] The gaseous circulating working fluid from the hot side outlet of the regenerator 7 enters the cooler 6 and the cryogenic heat exchanger 3, where its temperature heats the cooling water 14 to provide heating return water for users. The gaseous circulating working fluid then enters the cryogenic heat exchanger 3 to absorb the cold energy from the cryogenic storage tank 4. After its temperature is further reduced, it enters the cryogenic compressor 2, completing one discharge cycle. In some embodiments of this disclosure, before opening the outlet of the high-temperature storage tank 10, the outlet temperature of the cryogenic compressor 2 can be maintained at a certain rate to rise to the second temperature threshold T1 and remain constant in subsequent steps by controlling the flow rate of the cooling water 14 and / or the flow rate of the cold storage medium from the cryogenic storage tank 4 through the cryogenic heat exchanger 3 into the high-temperature storage tank 5.

[0040] In some embodiments of this disclosure, the cold storage medium in the low-temperature cold storage tank 4 and the high-temperature cold storage tank 5 can be methanol, ethanol, ethylene glycol, calcium chloride aqueous solution or a mixture thereof, or it can be a phase change material such as ice slurry.

[0041] By implementing the embodiments of this disclosure, an additional heat exchange device is added to the power generation process of the heat pump energy storage system. This heat exchange device can preheat the working fluid to increase the inlet temperature of the high-temperature expander during discharge, thereby rapidly increasing the system temperature and improving the system's grid dispatch load response capability. The activation or deactivation of the heat exchange device can be flexibly controlled according to the temperature of the system's working fluid through the first and second valves.

[0042] Figure 2 This is a flowchart illustrating a control method for a heat pump energy storage system provided in an embodiment of this disclosure. The heat pump energy storage system is any of the heat pump energy storage systems described in the above embodiments. The discharge process of the heat pump energy storage system is a positive Brayton cycle, utilizing the stored heat and cold energy to generate electrical energy. Figure 2 As shown, the control method for this heat pump energy storage system may include the following steps:

[0043] Step 201: In response to the heat pump energy storage system receiving a power generation command, the second and fourth valves are opened, the first and third valves are closed, and the outlet of the high-temperature heat storage tank is closed.

[0044] When the heat pump energy storage system receives a power generation command, it closes the first valve 16 and the third valve 18, and opens the second valve 15 and the fourth valve 17. The electric motor 1 starts at a certain rate, consuming electrical energy to drive the cryogenic compressor 2, gradually increasing the temperature and pressure of the gaseous circulating working fluid. The gaseous circulating working fluid enters the cold side inlet of the regenerator 7, and after preheating by the heat exchanger 8, it enters the high-temperature heat exchanger 11. At this time, the outlet of the high-temperature heat storage tank 10 is closed, and the circulation of the heat storage medium in the high-temperature heat storage tank 10 is not started, so the high-temperature heat exchanger 11 is not activated. The gaseous circulating working fluid directly enters the high-temperature expander 12 to perform work, and the working fluid becomes a low-temperature, low-pressure state. Simultaneously, the high-temperature expander 12 drives the generator 13 to generate electricity. The third valve 18 is closed, and the fourth valve 17 is opened, bypassing the hot side of the regenerator 7, allowing the working fluid at the outlet of the high-temperature expander 12 to directly enter the cryogenic compressor 2. After preheating by the heat exchanger 8, the outlet temperature of the cryogenic compressor 2 gradually increases.

[0045] Step 202: Determine that the outlet temperature of the cryogenic compressor has reached the second temperature threshold, and open the outlet of the high-temperature heat storage tank.

[0046] When the outlet temperature of the cryogenic compressor 2 reaches the second temperature threshold T1, the outlet of the high-temperature heat storage tank 10 is opened, and the heat storage medium in the high-temperature heat storage tank 10 is circulated. The thermal energy of the heat storage medium in the high-temperature heat storage tank 10 is used to heat the working fluid entering the cold side of the high-temperature heat exchanger 11, thereby enabling the high-temperature heat exchanger 11 to be put into operation and further increasing the temperature of the medium entering the high-temperature expander 12. In some embodiments of this disclosure, the temperature of the gaseous circulating medium entering the high-temperature expander 12 can be gradually increased at a certain rate by controlling the flow rate of the heat storage medium at the outlet of the high-temperature heat storage tank 10.

[0047] Step 203: Determine that the outlet temperature of the high-temperature expander has reached the second temperature threshold, close the fourth valve, and open the third valve.

[0048] When the outlet temperature of the high-temperature expander 12 reaches the second temperature threshold T1, the fourth valve 17 is closed and the third valve 18 is opened, activating the hot side of the regenerator 7. The working fluid on the hot side of the regenerator 7 exchanges heat with the working fluid on its cold side. By activating the hot side of the regenerator 7, the temperature of the gaseous circulating medium entering the high-temperature expander 12 is increased until it reaches the rated temperature T3 at the inlet of the high-temperature expander 12, satisfying the response conditions for the heat pump energy storage system to participate in peak shaving. It can operate at peak load during peak periods through rapid response, adapting to the faster dispatch response of the power grid. In some embodiments of this disclosure, the temperature of the gaseous circulating medium entering the high-temperature expander 12 can be gradually increased at a certain rate by repeatedly controlling the rate of increase of the heat storage medium flow rate.

[0049] Step 204: Determine that the temperature at the cold side outlet of the regenerator has reached the third temperature threshold, open the first valve, and close the second valve.

[0050] When the cold side outlet temperature of the regenerator 7 reaches the third temperature threshold T2, it indicates that the working fluid in the system has been heated to a certain degree. At this time, there is no need for the heat exchanger 8 to continue heating. Open the first valve 16, close the second valve 15, and bypass the heat exchanger 8.

[0051] In some embodiments of this disclosure, steps 201-203 can be implemented as independent embodiments, sequentially introducing the heating working fluid into the heat exchanger 8, the high-temperature heat exchanger 11, and the regenerator 7. During this process, the temperature of the cold-side outlet of the regenerator is monitored in real time. Once the temperature of the cold-side outlet of the regenerator reaches the third temperature threshold, step 204 is executed, bypassing the heat exchanger 8.

[0052] By implementing the embodiments of this disclosure, during the power generation process of the heat pump energy storage system, additional heat exchange equipment is used to preheat the working fluid, increasing the inlet temperature of the high-temperature expander during discharge, rapidly raising the system temperature, and significantly shortening the start-up time of the heat pump energy storage system. This improves the system's grid dispatch load response capability, provides stable output, and enhances the system's energy utilization efficiency.

[0053] Figure 3 This is a schematic diagram of a control device for a heat pump energy storage system provided in an embodiment of this disclosure. The heat pump energy storage system is the heat pump energy storage system described in any of the above embodiments. Figure 3 As shown, the control device of the heat pump energy storage system may include: a first control module 301, a second control module 302, a third control module 303 and a fourth control module 304.

[0054] The first control module 301 is used to respond to the heat pump energy storage system receiving a power generation command, open the second valve 15 and the fourth valve, close the first valve and the third valve, and close the outlet of the high-temperature heat storage tank.

[0055] The second control module 302 is used to determine when the outlet temperature of the cryogenic compressor reaches the second temperature threshold and to open the outlet of the high-temperature heat storage tank.

[0056] The third control module 303 is used to determine when the outlet temperature of the high-temperature expander reaches the second temperature threshold, close the fourth valve, and open the third valve.

[0057] The fourth control module 304 is used to determine when the temperature at the cold side outlet of the regenerator reaches the third temperature threshold, to open the first valve and close the second valve.

[0058] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0059] To implement the above embodiments, this disclosure also proposes an electronic device, including: a processor and a memory communicatively connected to the processor; the memory stores computer execution instructions; the processor executes the computer execution instructions stored in the memory to implement the method provided in the foregoing embodiments.

[0060] To implement the above embodiments, this disclosure also proposes a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the methods provided in the foregoing embodiments.

[0061] In the foregoing descriptions of the embodiments, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0062] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0063] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing custom logic functions or processes, and the scope of preferred embodiments of this disclosure includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as will be understood by those skilled in the art to which embodiments of this disclosure pertain.

[0064] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0065] It should be understood that various parts of this disclosure can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0066] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0067] Furthermore, the functional units in the various embodiments of this disclosure can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

Claims

1. A heat pump energy storage system with fast discharge process initiation, characterized in that, include: Electric motors, cryogenic compressors, regenerators, heat exchange equipment, cryogenic heat storage tanks, high-temperature heat storage tanks, cryogenic heat storage tanks, high-temperature expanders, and generators; The electric motor is connected to the cryogenic compressor, the cryogenic compressor is coaxially connected to the high-temperature expander, the high-temperature expander is connected to the generator, the outlet of the cryogenic compressor is connected to the cold-side inlet of the regenerator, the cold-side outlet of the regenerator is connected to the cold-side inlet of the cryogenic heat storage tank through a first valve, the cold-side outlet of the regenerator is connected to the cold-side inlet of the cryogenic heat storage tank through a second valve and the heat exchange equipment, the hot-side inlet of the cryogenic heat storage tank is connected to the high-temperature heat storage tank, the hot-side outlet of the cryogenic heat storage tank is connected to the cryogenic heat storage tank, the cold-side outlet of the cryogenic heat storage tank is connected to the inlet of the high-temperature expander, the outlet of the high-temperature expander is connected to the hot-side inlet of the regenerator through a third valve, the outlet of the high-temperature expander is connected to the hot-side outlet of the regenerator through a fourth valve, and the hot-side outlet of the regenerator is connected to the inlet of the cryogenic compressor. The temperature of the heat storage medium in the heat storage and exchange equipment is higher than a first temperature threshold.

2. The system of claim 1, wherein, The hot-side outlet of the regenerator and the inlet of the cryogenic compressor include a cryogenic heat exchanger and a cooler; wherein, the hot-side outlet of the regenerator is connected to the hot-side inlet of the cooler, the hot-side outlet of the cooler is connected to the hot-side inlet of the cryogenic heat exchanger, the hot-side outlet of the cryogenic heat exchanger is connected to the inlet of the cryogenic compressor, the cold-side inlet of the cooler is connected to cooling water, the cold-side inlet of the cryogenic heat exchanger is connected to a cryogenic cold storage tank, and the cold-side outlet of the cryogenic heat exchanger is connected to a high-temperature cold storage tank.

3. The system of claim 1 or 2, wherein, The heat storage and exchange equipment can be any of the following: a stacked bed, a fluidized bed, various types of heat storage equipment containing heat exchange tubes, and a combination of a heat storage medium container and a matching heat exchanger.

4. The system of claim 1 or 2, wherein, The heat storage medium in the low-temperature heat storage tank and the high-temperature heat storage tank is any one of the following: molten salt, heat transfer oil, solid material, or phase change material.

5. The system of claim 1 or 2, wherein, The cold storage medium in the low-temperature cold storage tank and the high-temperature cold storage tank is any one or more of the following: methanol, ethanol, ethylene glycol, and calcium chloride aqueous solution; Alternatively, the cold storage medium may be a phase change material.

6. A control method characterized by, The control method is applied to the heat pump energy storage system with rapid start-up during the discharge process as described in any one of claims 1-5, and the method includes the following steps: In response to the heat pump energy storage system receiving a power generation command, the second valve and the fourth valve are opened, the first valve and the third valve are closed, and the outlet of the high-temperature heat storage tank is closed; Once the outlet temperature of the cryogenic compressor reaches the second temperature threshold, the outlet of the high-temperature heat storage tank is opened. Once the outlet temperature of the high-temperature expander reaches the second temperature threshold, the fourth valve is closed and the third valve is opened. Once the temperature at the cold side outlet of the regenerator reaches the third temperature threshold, the first valve is opened and the second valve is closed.

7. A control device characterized by comprising: The control device is applied to the heat pump energy storage system with rapid start-up during the discharge process as described in any one of claims 1-5, and the device comprises: The first control module is used to respond to the heat pump energy storage system receiving a power generation command by opening the second valve and the fourth valve, closing the first valve and the third valve, and closing the outlet of the high-temperature heat storage tank; The second control module is used to determine when the outlet temperature of the cryogenic compressor reaches the second temperature threshold and to open the outlet of the high-temperature heat storage tank. The third control module is used to determine when the outlet temperature of the high-temperature expander reaches the second temperature threshold, close the fourth valve, and open the third valve; The fourth control module is used to determine that the temperature at the cold side outlet of the regenerator reaches the third temperature threshold, open the first valve, and close the second valve.

8. An electronic device, comprising: include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory to implement the method as described in claim 6.

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