Energy storage peak shaving system coupled with heat pump and method

Abstract

The present application relates to the technical field of power grid peak shaving and comprehensive energy utilization, in particular to a heat pump coupled energy storage peak shaving system and method. The system comprises a low-parameter heat source unit, a heat pump temperature raising unit, a heat storage unit and a high-parameter power generation unit. The low-parameter heat source unit outputs heat source medium carrying heat; the heat pump temperature raising unit is in heat exchange connection with the low-parameter heat source unit, absorbs the heat of the heat source medium output by the low-parameter heat source unit and heats it; the heat storage unit is in heat exchange connection with the heat pump temperature raising unit, absorbs and stores the heat output by the heat pump temperature raising unit; and the high-parameter power generation unit is in heat exchange connection with the heat storage unit, absorbs the heat released by the heat storage unit and generates power. The system can effectively improve the power generation capacity of the high-parameter power generation unit, realize efficient energy conversion and utilization across time periods, and thus has flexible peak shaving capacity.

Description

Technical Field

[0001] This invention relates to the field of power grid peak shaving and integrated energy utilization technology, specifically to a heat pump coupled energy storage peak shaving system and method. Background Technology

[0002] With increasing fluctuations in the net load of the power system, traditional power sources and integrated energy systems need to undertake peak-shaving tasks at higher frequencies and with greater magnitudes. In the operation of some power generation or supply systems, such as nuclear power, geothermal power, or industrial waste heat power generation, low-parameter heat with low temperature, pressure, or work capacity is typically continuously generated. Although this type of low-parameter heat has good stability, its energy conversion efficiency is low when directly used for power generation or peak shaving due to temperature limitations.

[0003] Under the existing operation and regulation mode, the aforementioned low-parameter heat is often difficult to fully absorb during off-peak hours. Simply reducing system output can easily lead to insufficient utilization of the underlying heat; if this heat is directly discharged, it will reduce the overall comprehensive energy utilization efficiency of the system. On the other hand, during peak hours, the grid load demand is higher, and high-parameter power generation systems often need to have stronger generation capacity and peak-shaving response capabilities.

[0004] In existing technologies, low-parameter heat sources and high-parameter power generation systems mostly operate independently, lacking effective energy interaction and coordinated matching. This makes it difficult to utilize low-parameter heat through cross-time conversion, and also makes it difficult to effectively improve the power generation capacity of high-parameter power generation systems. Summary of the Invention

[0005] To address the above problems, this invention provides a heat pump coupled energy storage peak-shaving system and method, which can effectively absorb the low-grade heat generated by the low-parameter heat source system during off-peak hours and convert it into the increased power generation capacity of the high-parameter power generation system during peak hours, thereby improving the peak-shaving capacity and comprehensive energy utilization efficiency of the power system.

[0006] The first aspect of this invention provides a heat pump coupled energy storage and peak-shaving system, comprising a low-parameter heat source unit, a heat pump temperature-raising unit, a thermal storage unit, and a high-parameter power generation unit. The low-parameter heat source unit outputs a heat source medium carrying heat; the heat pump temperature-raising unit is heat-exchange connected to the low-parameter heat source unit, absorbing and heating the heat source medium output by the low-parameter heat source unit; the thermal storage unit is heat-exchange connected to the heat pump temperature-raising unit, absorbing and storing the heat output by the heat pump temperature-raising unit; and the high-parameter power generation unit is heat-exchange connected to the thermal storage unit, absorbing the heat released by the thermal storage unit and generating electricity.

[0007] Optionally, the heat source medium circulates within a low-parameter heat source unit, which includes: a low-parameter heat source body; a heat extraction valve whose heat source medium inlet is connected to the heat source medium outlet of the low-parameter heat source body; a heat source-side expander whose heat source medium inlet is connected to the first heat source medium outlet of the heat extraction valve; a heat source-side cooler whose heat source medium inlet is connected to the heat source medium outlet of the heat source-side expander; and a heat source-side circulation pump whose heat source medium inlet is connected to the heat source medium outlet of the heat source-side cooler and whose heat source medium outlet is connected to the heat source medium inlet of the low-parameter heat source body.

[0008] Optionally, the heat pump heating unit has a circulating heat pump working fluid. The heat pump heating unit includes: a heat pump absorber whose heat source medium inlet is connected to the second heat source medium outlet of the heat exchange valve of the low-parameter heat source unit, and whose internal heat pump working fluid exchanges heat with the heat source medium; a compressor whose heat pump working fluid inlet is connected to the heat pump working fluid outlet of the heat pump absorber; a heat pump exotherm whose heat pump working fluid inlet is connected to the heat pump working fluid outlet of the compressor; and an expander whose heat pump working fluid inlet is connected to the heat pump working fluid outlet of the heat pump exotherm and whose heat pump working fluid outlet is connected to the heat pump working fluid inlet of the heat pump absorber.

[0009] Optionally, the thermal storage unit has a circulating thermal storage medium. The thermal storage unit includes: a thermal storage medium pump whose outlet is connected to the thermal storage medium inlet of the heat pump heat exchanger and whose thermal storage medium enters the heat pump heat exchanger to exchange heat with the heat pump working fluid; a high-temperature storage tank whose inlet is connected to the thermal storage medium outlet of the heat pump heat exchanger; a heat release heat exchanger whose inlet is connected to the thermal storage medium outlet of the high-temperature storage tank; and a low-temperature storage tank whose inlet is connected to the thermal storage medium outlet of the heat release heat exchanger and whose outlet is connected to the thermal storage medium inlet of the thermal storage medium pump.

[0010] Optionally, the high-parameter power generation unit has a circulating power generation working fluid. The high-parameter power generation unit includes: a steam turbine whose power generation working fluid inlet is connected to the power generation working fluid outlet of a heat release heat exchanger; a cooler whose power generation working fluid inlet is connected to the working fluid outlet of the steam turbine; and a working fluid pump whose power generation working fluid inlet is connected to the power generation working fluid outlet of the cooler, whose power generation working fluid outlet is connected to the power generation working fluid inlet of the heat release heat exchanger, and whose power generation working fluid entering the heat release heat exchanger exchanges heat with the heat storage medium.

[0011] Optionally, it also includes a control unit, which is connected to the low-parameter heat source unit, the heat pump temperature-raising unit, the thermal storage unit, and the high-parameter power generation unit via signals.

[0012] Optionally, the low-parameter heat source unit includes at least one of a nuclear power generation system, a geothermal power generation system, a solar thermal power generation system, a biomass power generation system, a waste incineration power generation system, an industrial waste heat power generation system, a gas turbine waste heat power generation system, a fuel cell waste heat power generation system, and an organic Rankine cycle power generation system; the heat pump temperature-raising unit includes at least one of a reverse Carnot cycle heat pump, a vapor compression cycle heat pump, a reverse Brayton cycle heat pump, a transcritical CO2 cycle heat pump, a supercritical CO2 cycle heat pump, an absorption heat pump, an adsorption heat pump, a Stirling heat pump, a vapor recompression heat pump, a thermochemical heat pump, or a combined cycle heat pump; the heat storage unit adopts at least one of sensible heat storage, latent heat storage, and thermochemical heat storage; the high-parameter power generation unit includes at least one of a steam Rankine cycle power generation system, a gas power generation system, a combined cycle power generation system, a solar thermal power generation system, a biomass power generation system, a waste incineration power generation system, a geothermal power generation system, an organic Rankine cycle power generation system, and a supercritical CO2 Brayton cycle power generation system.

[0013] Optionally, the heat source medium includes at least one of steam, water, geothermal water, brine, heat transfer oil, molten salt, flue gas, exhaust gas, organic working fluid, supercritical CO2, air, or nitrogen; the heat pump working fluid includes at least one of water vapor, air, nitrogen, helium, argon, carbon dioxide, ammonia, hydrocarbon working fluid, or hydrofluoroolefin working fluid; the heat storage medium includes at least one of molten salt, heat transfer oil, water, concrete, ceramics, sand and gravel, metal, slag, solid particles, inorganic salts, hydrated salts, paraffin wax, metal alloys, adsorbent materials, thermochemical reaction materials, or combinations thereof; and the power generation working fluid includes at least one of water, main steam, reheat steam, air, fuel gas, flue gas, heat transfer oil, molten salt, organic working fluid, or supercritical CO2.

[0014] A second aspect of the present invention provides a heat pump coupled energy storage peak shaving method, applicable to the above-mentioned heat pump coupled energy storage peak shaving system, comprising the following steps: Heat source medium introduction step: The low-parameter heat source unit outputs a heat source medium with heat, and the heat source medium is introduced into the heat pump temperature raising unit; The heat pump circulation heating process involves the heat pump heating unit absorbing and heating the heat source medium. Energy storage steps for thermal storage medium: During off-peak electricity hours, heat from the heat pump heating unit is input into the thermal storage unit for storage; Release for power generation steps: During peak power periods, the heat stored in the thermal storage unit is released to generate electricity.

[0015] Optionally, the method further includes a dynamic control step: using a control unit to adjust the heat extraction capacity of the heat extraction valve to the heat source medium, the operating load of the heat pump heating unit, the charging and discharging power of the heat storage unit, and the heat received by the high-parameter power generation unit based on the acquired grid load demand, the operating parameters of the low-parameter heat source unit, the operating status of the heat pump heating unit, the heat storage status of the heat storage unit, and the output demand of the high-parameter power generation unit.

[0016] The heat pump-coupled energy storage peak-shaving system provided by this invention provides heat through a low-parameter heat source unit, a heat pump temperature-raising unit raises the temperature of the low-grade heat, a heat storage unit stores heat across time periods, and generates electricity on the high-parameter power generation unit side. This structure can convert low-parameter heat, which is difficult to fully absorb during off-peak hours, into high-grade heat for storage, and release it to the high-parameter power generation unit during peak hours when grid load demand is high. This effectively improves the power generation capacity of the high-parameter power generation unit, achieves efficient energy conversion and utilization across time periods, and significantly enhances the flexible peak-shaving capability of the entire system. Attached Figure Description

[0017] Figure 1 This is a block diagram of the overall structure of the heat pump coupled energy storage and peak shaving system provided in the first embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the structure of a heat pump coupled energy storage and peak shaving system provided in the first embodiment of the present invention.

[0019] Figure 3 A flowchart of a heat pump coupled energy storage peak shaving method provided in the second embodiment of the present invention.

[0020] Figure reference numerals: 100-Energy storage and peak shaving system; 1-Low parameter heat source unit; 11-Low parameter heat source body; 12-Heat extraction valve; 13-Heat source side expander; 14-Heat source side cooler; 15-Heat source side circulating pump; 2-Heat pump temperature raising unit; 21-Heat pump absorber; 22-Compressor; 23-Heat pump exothermic device; 24-Expander; 3-Heat storage unit; 31-Low temperature storage tank; 32-High temperature storage tank; 33-Heat release exchanger; 34-Heat storage medium pump; 4-High parameter power generation system; 41-Steam turbine; 42-Cooler; 43-Working fluid pump; 5-Control unit; 51-Heat source side control line; 52-Heat pump side control line; 53-Heat storage side control line; 54-High parameter power generation system control line. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] <First Implementation Method> This embodiment provides a heat pump coupled energy storage and peak-shaving system 100. For example... Figure 1 and Figure 2 As shown, the energy storage and peak shaving system 100 includes a low-parameter heat source unit 1, a heat pump temperature raising unit 2, a thermal storage unit 3, and a high-parameter power generation unit 4.

[0023] In this embodiment, the low-parameter heat source unit 1 is used to output a heat source medium carrying heat. In actual operation, the low-parameter heat source unit 1 often continuously generates low-grade heat with low temperature and pressure. The low-parameter heat source unit 1 contains a circulating heat source medium. Specifically, the low-parameter heat source unit 1 includes a low-parameter heat source body 11, a heat extraction valve 12, a heat source-side expander 13, a heat source-side cooler 14, and a heat source-side circulating pump 15. (Reference) Figure 2 The heat source medium inlet of the heat extraction valve 12 is connected to the heat source medium outlet side of the low-parameter heat source body 11. The first outlet of the heat extraction valve 12 serves as the first heat source medium outlet and is connected to the heat source medium inlet of the heat source side expander 13. The heat source medium outlet of the heat source side expander 13 is connected to the heat source medium inlet of the heat source side cooler 14. The heat source medium outlet of the heat source side cooler 14 is connected to the heat source medium inlet of the heat source side circulating pump 15. The heat source medium outlet of the heat source side circulating pump 15 is connected to the heat source medium inlet of the low-parameter heat source body 11. Through the above settings, the heat extraction valve 12 can flexibly adjust the flow ratio. Unused heat source medium enters the heat source side expander 13 to perform work, and then returns to the low-parameter heat source body 11 after cooling and pumping, achieving a stable circulation of the heat source working medium. This embodiment, by setting up a heat extraction valve, a heat source-side expander, and a heat source-side cooler, can flexibly adjust the flow rate of the heat source medium entering the heat pump heating unit 2, while expanding and cooling the heat source medium that does not enter the heat pump heating unit 2, further improving the system operation flexibility and energy cascade utilization level on the low-parameter heat source body 11 side.

[0024] It should be noted that the low-parameter heat source unit 1 may include at least one of the following: nuclear power generation system, geothermal power generation system, solar thermal power generation system, biomass power generation system, waste incineration power generation system, industrial waste heat power generation system, gas turbine waste heat power generation system, fuel cell waste heat power generation system, and organic Rankine cycle power generation system. The heat source medium output by the low-parameter heat source unit 1 may be steam, water, geothermal water, brine, heat transfer oil, molten salt, flue gas, exhaust gas, organic working fluid, supercritical carbon dioxide, air, or nitrogen.

[0025] In this embodiment, the heat pump temperature-raising unit 2 is heat-exchange connected to the low-parameter heat source unit 1. The heat pump temperature-raising unit 2 absorbs heat from the heat source medium output by the low-parameter heat source unit 1 and heats it. The heat pump temperature-raising unit 2 contains a circulating heat pump working fluid. Specifically, the heat pump temperature-raising unit 2 includes a heat pump absorber 21, a compressor 22, a heat pump exothermic generator 23, and an expander 24. (Reference) Figure 2 The other outlet of the heat valve 12 serves as the second heat source medium outlet, connected to the heat source medium inlet of the heat pump absorber 21. The heat pump working fluid within the heat pump absorber 21 exchanges heat with the incoming heat source medium. The heat pump working fluid outlet of the heat pump absorber 21 is connected to the heat pump working fluid inlet of the compressor 22. The heat pump working fluid outlet of the compressor 22 is connected to the heat pump working fluid inlet of the heat pump exothermic device 23. The heat pump working fluid outlet of the heat pump exothermic device 23 is connected to the heat pump working fluid inlet of the expander 24. The heat pump working fluid outlet of the expander 24 is connected to the heat pump working fluid inlet of the heat pump absorber 21. During off-peak electricity hours, the heat pump working fluid absorbs low-grade heat in the heat pump absorber 21. This heat pump working fluid then enters the compressor 22, where it performs work to increase temperature and pressure. The heated heat pump working fluid then enters the heat pump exothermic device 23, releasing high-grade heat. After releasing heat, the heat pump working fluid is cooled and depressurized by the expander 24 and then returned to the heat pump receiver 21 to complete the cycle. This embodiment achieves the heating and pressurization and cooling and depressurization cycle of the heat pump working fluid by setting up a compressor and an expander and cooperating with each other, efficiently converting low-grade heat into high-grade heat.

[0026] It should be noted that the heat pump temperature-raising unit 2 may include at least one of the following: a reverse Carnot cycle heat pump, a vapor compression cycle heat pump, a reverse Brayton cycle heat pump, a transcritical carbon dioxide cycle heat pump, a supercritical carbon dioxide cycle heat pump, an absorption heat pump, an adsorption heat pump, a Stirling heat pump, a vapor recompression heat pump, a thermochemical heat pump, or a combined cycle heat pump. For example, when a transcritical carbon dioxide cycle is used, the heat pump heat exchanger 23 is specifically a gas cooler; when an absorption cycle is used, the compressor 22 described above can be replaced by a combination structure of an absorber, a generator, and a heat pump cycle pump. The heat pump working fluid may be water vapor, air, nitrogen, helium, argon, carbon dioxide, ammonia, hydrocarbon working fluid, hydrofluoroolefin working fluid, or a mixture thereof.

[0027] In this embodiment, the heat storage unit 3 is heat-exchange connected to the heat pump heating unit 2. The heat storage unit 3 absorbs and stores the heat output by the heat pump heating unit 2. The heat storage unit 3 contains a circulating heat storage medium. Specifically, the heat storage unit 3 includes a heat storage medium pump 34, a high-temperature storage tank 32, a heat release heat exchanger 33, and a low-temperature storage tank 31. (Reference) Figure 2 The heat storage medium outlet of the heat storage medium pump 34 is connected to the heat storage medium inlet of the heat pump heat exchanger 23. The heat storage medium entering the heat pump heat exchanger 23 exchanges heat with the heat pump working fluid. The heat storage medium inlet of the high-temperature storage tank 32 is connected to the heat storage medium outlet of the heat pump heat exchanger 23. The heat storage medium inlet of the heat release heat exchanger 33 is connected to the heat storage medium outlet of the high-temperature storage tank 32. The heat storage medium inlet of the low-temperature storage tank 31 is connected to the heat storage medium outlet of the heat release heat exchanger 33. The heat storage medium outlet of the low-temperature storage tank 31 is connected to the heat storage medium inlet of the heat storage medium pump 34. In heat storage mode, the heat storage medium pump 34 sends the heat storage medium from the low-temperature storage tank 31 into the heat pump heat exchanger 23. After absorbing heat, the heat storage medium enters the high-temperature storage tank 32 for storage. In heat release mode, the high-temperature heat storage medium in the high-temperature storage tank 32 enters the heat release heat exchanger 33 to release heat, and the released heat storage medium flows back to the low-temperature storage tank 31. This embodiment achieves stable storage of high-grade heat during off-peak hours and efficient release during peak hours through the cooperation of high-temperature storage tank 32, low-temperature storage tank 31, heat pump heat exchanger 23 and heat release heat exchanger 33, thereby ensuring the feasibility of energy transfer across time periods.

[0028] It should be noted that the thermal storage unit 3 can employ at least one of sensible heat storage, latent heat storage, or thermochemical heat storage. When latent heat storage is used, the cryogenic storage tank 31 and the high-temperature storage tank 32 can be replaced by a phase change thermal storage device. When thermochemical heat storage is used, the cryogenic storage tank 31 and the high-temperature storage tank 32 can be replaced by a thermochemical heat storage reactor. The thermal storage medium can be molten salt, heat transfer oil, water, concrete, ceramics, sand and gravel, metal, slag, solid particles, inorganic salts, hydrated salts, paraffin wax, metal alloys, adsorbent materials, thermochemical reaction materials, or combinations thereof.

[0029] In this embodiment, the high-parameter power generation unit 4 is heat-exchange connected to the thermal storage unit 3. The high-parameter power generation unit 4 absorbs the heat released by the thermal storage unit 3 and generates electricity. The high-parameter power generation unit 4 contains a circulating working fluid. Specifically, the high-parameter power generation unit 4 includes a steam turbine 41, a cooler 42, and a working fluid pump 43. (Reference) Figure 2The working fluid inlet of the steam turbine 41 is connected to the working fluid outlet of the heat release heat exchanger 33. The working fluid inlet of the cooler 42 is connected to the working fluid outlet of the steam turbine 41. The working fluid inlet of the working fluid pump 43 is connected to the working fluid outlet of the cooler 42. The working fluid outlet of the working fluid pump 43 is connected to the working fluid inlet of the heat release heat exchanger 33. The working fluid entering the heat release heat exchanger 33 exchanges heat with the heat storage medium. During peak power periods, the circulating working fluid of the high-parameter power generation unit 4 absorbs the heat released by the high-temperature heat storage medium in the heat release heat exchanger 33. The heated circulating working fluid enters the steam turbine 41 to expand and perform work, thereby increasing the power generation capacity. After performing work, the working fluid is cooled by the cooler 42 and then sent back to the heat release heat exchanger 33 by the working fluid pump 43 to form a cycle. The high-parameter power generation unit 4 provided in this embodiment enables the high-grade heat released by the thermal storage unit 3 to directly heat the power generation working fluid and drive the steam turbine 41 to do work, ensuring the system's power generation capacity during peak power periods.

[0030] It should be noted that the high-parameter power generation unit 4 may include at least one of the following: a steam Rankine cycle power generation system, a gas-fired power generation system, a combined cycle power generation system, a solar thermal power generation system, a biomass power generation system, a waste incineration power generation system, a geothermal power generation system, an organic Rankine cycle power generation system, and a supercritical carbon dioxide Brayton cycle power generation system. The working fluid may be water, main steam, reheat steam, air, gas, flue gas, heat transfer oil, molten salt, organic working fluid, or supercritical carbon dioxide. Correspondingly, the steam turbine 41 may also be replaced by other power-operating expansion machinery such as a gas turbine.

[0031] In addition, the heat pump-coupled energy storage peak-shaving system 100 also includes a control unit 5. (Reference) Figure 1 The control unit 5 is connected to the low-parameter heat source unit 1, the heat pump heating unit 2, the thermal storage unit 3, and the high-parameter power generation unit 4 via signals. The control unit 5 can dynamically adjust the heat extraction capacity of the heat extraction valve 12, the operating load of the heat pump heating unit 2, the charging and discharging power of the thermal storage unit 3, and the heat received by the high-parameter power generation unit 4 based on the grid load demand, the operating parameters of the low-parameter heat source unit 1, the operating status of the heat pump heating unit 2, the thermal storage status of the thermal storage unit 3, and the output demand of the high-parameter power generation unit 4. This embodiment achieves comprehensive and coordinated control of each unit through the control unit 5, enabling the heat pump-coupled energy storage peak-shaving system 100 to dynamically adjust the heat extraction, heating, storage, and release processes according to the real-time load demand of the grid, thereby enhancing the system's load response speed and automated peak-shaving performance.

[0032] The heat pump-coupled energy storage peak-shaving system 100 provided in this embodiment can effectively solve the technical problems of difficulty in absorbing low-grade heat during off-peak hours and insufficient power generation capacity of high-parameter power generation systems during peak hours. Through the coupling of the low-parameter heat source unit 1 and the heat pump temperature-raising unit 2, the heat pump absorbs low-parameter heat that is originally difficult to utilize efficiently during off-peak hours and significantly upgrades it to high-grade heat. Combined with the heat storage buffering effect of the heat storage unit 3, the converted high-grade heat is stored across time periods. During peak hours, the heat storage unit 3 releases the high-grade heat to the high-parameter power generation unit 4, heating the power generation working fluid and driving the turbine 41 to generate electricity. This system structure deeply integrates heat quality improvement, cross-time energy storage, and peak-shaving power generation, not only avoiding the waste of low-grade heat during off-peak hours but also significantly improving the power output and response speed of the high-parameter power generation unit 4 during peak hours, greatly enhancing the overall power system's flexible peak-shaving capability and comprehensive energy utilization efficiency.

[0033] <Second Implementation Method> This embodiment provides a heat pump coupled energy storage peak shaving method, applicable to the heat pump coupled energy storage peak shaving system 100 described in the first embodiment. (Reference) Figure 3 The method includes the following steps: Step S1: The low-parameter heat source unit 1 outputs a heat source medium containing heat and introduces it into the heat pump heating unit 2. Specifically, during off-peak electricity hours, the control unit 5 opens the heat extraction valve 12, allowing a portion of the heat source-side working fluid in the low-parameter heat source body 11 to enter the heat pump absorber 21. After releasing heat in the heat pump absorber 21, the heat source medium returns to the low-parameter heat source body 11 via the heat source-side cooler 14 and the heat source-side circulation pump 15. The low-grade heat carried by this heat source medium is at a temperature of 300°C. + 50℃.

[0034] Heat pump circulation heating step S2: The heat pump heating unit 2 absorbs and heats the heat source medium. Specifically, the heat pump working fluid absorbs the low-grade heat in the heat pump absorber 21, and then enters the compressor 22 for heating and pressurization. The heated heat pump working fluid enters the heat pump exotherm 23 to release the high-grade heat. After releasing heat, the heat pump working fluid is cooled and depressurized by the expander 24 and returns to the heat pump absorber 21 to complete the cycle. Through this heat pump circulation process, for example, approximately 300°C can be heated. + The heat from a low-grade heat source at 50°C is significantly increased to approximately 620°C. + High-grade heat at 50℃.

[0035] Energy storage step S3: During off-peak electricity hours, heat from the heat pump heating unit 2 is input into the heat storage unit 3 for storage. Specifically, the heat storage medium pump 34 is started, causing the heat storage medium in the low-temperature storage tank 31 to enter the heat pump heat exchanger 23 to absorb the high-grade heat released by the heat pump working fluid. After absorbing heat, the heat storage medium becomes a high-temperature heat storage medium and enters the high-temperature storage tank 32 for storage, thereby achieving effective energy enrichment and storage during periods of low grid load.

[0036] Step S4 for releasing heat to generate electricity: During peak power periods, the heat stored in the thermal storage unit 3 is released to generate electricity. Specifically, when the power grid is in peak power period, the control unit 5 activates the relevant thermal storage side pump valves, allowing the high-temperature thermal storage medium in the high-temperature storage tank 32 to enter the heat release heat exchanger 33. The high-temperature thermal storage medium transfers heat to the circulating working fluid of the high-parameter power generation unit 4 in the heat release heat exchanger 33. The released thermal storage medium returns to the low-temperature storage tank 31. The heated circulating working fluid, such as feedwater, main steam, or supercritical carbon dioxide, enters the turbine 41 to expand and perform work, thereby effectively increasing the power output of the high-parameter power generation unit 4.

[0037] Dynamic control step S5: During the overall system operation, the control unit 5 dynamically adjusts the heat extraction capacity of the heat extraction valve 12, the operating load of the heat pump heating unit 2, the charging and discharging power of the heat storage unit 3, and the heat received by the high-parameter power generation unit 4 based on the acquired grid load demand, the operating parameters of the low-parameter heat source unit 1, the operating status of the heat pump heating unit 2, the heat storage status of the heat storage unit 3, and the output demand of the high-parameter power generation unit 4. Through closed-loop coordinated regulation, the system's operating conditions are ensured to remain stable.

[0038] The heat pump-coupled energy storage peak-shaving method provided in this embodiment actively absorbs low-grade heat from low-parameter heat sources during off-peak hours and converts it into high-grade heat for storage through time-series control and cross-system energy allocation. During peak hours, this high-grade heat is then released directionally to high-parameter power generation systems. This method achieves efficient cross-time utilization of low-grade heat, not only fully utilizing idle heat sources but also effectively solving the problem of limited power generation capacity of high-parameter power generation systems during peak hours, significantly improving the overall peak-shaving response capability and comprehensive energy utilization efficiency of the system.

[0039] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A heat pump coupled energy storage and peak-shaving system, characterized in that, include: Low-parameter heat source unit, outputting a heat source medium that carries heat; The heat pump heating unit is connected to the low-parameter heat source unit for heat exchange, and absorbs the heat from the heat source medium output by the low-parameter heat source unit and heats it. A heat storage unit is connected to the heat pump heating unit for heat exchange, and absorbs and stores the heat output by the heat pump heating unit. as well as A high-parameter power generation unit is connected to the thermal storage unit for heat exchange, absorbing the heat released by the thermal storage unit and generating electricity.

2. The heat pump coupled energy storage and peak-shaving system according to claim 1, characterized in that, The heat source medium circulates within a low-parameter heat source unit, which includes: Low-parameter heat source body; A heat extraction valve, the heat source medium inlet of which is connected to the heat source medium outlet of the low-parameter heat source body; The heat source side expander has its heat source medium inlet connected to the first heat source medium outlet of the heat extraction valve; A heat source-side cooler, wherein the heat source medium inlet is connected to the heat source medium outlet of the heat source-side expander; and The heat source side circulating pump has its heat source medium inlet connected to the heat source medium outlet of the heat source side cooler, and its heat source medium outlet connected to the heat source medium inlet of the low-parameter heat source body.

3. The heat pump coupled energy storage and peak-shaving system according to claim 2, characterized in that, The heat pump temperature-raising unit contains a circulating heat pump working fluid, and the heat pump temperature-raising unit includes: The heat pump absorber has its heat source medium inlet connected to the second heat source medium outlet of the heat extraction valve of the low-parameter heat source unit, and the heat source medium is exchanged with the heat pump working fluid in the heat pump absorber. The compressor has its heat pump working fluid inlet connected to the heat pump working fluid outlet of the heat pump absorber. A heat pump heat exchanger, wherein the heat pump working fluid inlet is connected to the heat pump working fluid outlet of the compressor; And an expander, the heat pump working fluid inlet of which is connected to the heat pump working fluid outlet of the heat pump exotherm, and the heat pump working fluid outlet of which is connected to the heat pump working fluid inlet of the heat pump absorber.

4. The heat pump coupled energy storage and peak-shaving system according to claim 3, characterized in that, The thermal storage unit contains a circulating thermal storage medium, and the thermal storage unit includes: A heat storage medium pump, wherein the outlet of the heat storage medium is connected to the inlet of the heat storage medium of the heat pump heat exchanger, and the heat storage medium entering the heat pump heat exchanger exchanges heat with the heat pump working fluid. A high-temperature storage tank, the inlet of which is connected to the outlet of the heat pump heat exchanger; A heat release heat exchanger, the inlet of which is connected to the outlet of the heat storage medium of the high-temperature storage tank; The cryogenic storage tank has its heat storage medium inlet connected to the heat storage medium outlet of the heat release heat exchanger, and its heat storage medium outlet connected to the heat storage medium inlet of the heat storage medium pump.

5. The heat pump coupled energy storage and peak-shaving system according to claim 4, characterized in that, The high-parameter power generation unit contains a circulating power-generating working fluid, and the high-parameter power generation unit includes: The steam turbine has its power generation working fluid inlet connected to the power generation working fluid outlet of the heat release heat exchanger. A cooler, the inlet of which generates the working fluid is connected to the outlet of the steam turbine; The working fluid pump has its power generation working fluid inlet connected to the power generation working fluid outlet of the cooler, and its power generation working fluid outlet connected to the power generation working fluid inlet of the heat release heat exchanger. The power generation working fluid entering the heat release heat exchanger exchanges heat with the heat storage medium.

6. The heat pump coupled energy storage and peak-shaving system according to claim 5, characterized in that, It also includes a control unit, which is signal-connected to the low-parameter heat source unit, the heat pump temperature-raising unit, the thermal storage unit and the high-parameter power generation unit respectively.

7. The heat pump coupled energy storage and peak-shaving system according to claim 1, characterized in that, The low-parameter heat source unit includes at least one of the following: nuclear power generation system, geothermal power generation system, solar thermal power generation system, biomass power generation system, waste incineration power generation system, industrial waste heat power generation system, gas turbine waste heat power generation system, fuel cell waste heat power generation system, and organic Rankine cycle power generation system. The heat pump temperature-raising unit includes at least one of the following: reverse Carnot cycle heat pump, vapor compression cycle heat pump, reverse Brayton cycle heat pump, transcritical CO2 cycle heat pump, supercritical CO2 cycle heat pump, absorption heat pump, adsorption heat pump, Stirling heat pump, vapor recompression heat pump, thermochemical heat pump, or composite cycle heat pump. The thermal storage unit employs at least one of sensible thermal storage, latent thermal storage, and thermochemical thermal storage. The high-parameter power generation unit includes at least one of the following: steam Rankine cycle power generation system, gas-fired power generation system, combined cycle power generation system, solar thermal power generation system, biomass power generation system, waste incineration power generation system, geothermal power generation system, organic Rankine cycle power generation system, and supercritical CO2 Brayton cycle power generation system.

8. The heat pump coupled energy storage and peak-shaving system according to claim 6, characterized in that, The heat source medium includes at least one of steam, water, geothermal water, brine, heat transfer oil, molten salt, flue gas, exhaust gas, organic working fluid, supercritical CO2, air, or nitrogen. The heat pump working fluid includes at least one of water vapor, air, nitrogen, helium, argon, carbon dioxide, ammonia, hydrocarbon working fluid, and hydrofluoroolefin working fluid; The heat storage medium includes at least one of molten salt, heat transfer oil, water, concrete, ceramics, sand and gravel, metal, slag, solid particles, inorganic salt, hydrated salt, paraffin, metal alloy, adsorbent material, thermochemical reaction material, or a combination thereof; The power generation medium includes at least one of water, main steam, reheat steam, air, fuel gas, flue gas, heat transfer oil, molten salt, organic medium, and supercritical CO2.

9. A heat pump coupled energy storage peak shaving method, applicable to the heat pump coupled energy storage peak shaving system as described in any one of claims 1-8, characterized in that, Includes the following steps: Heat source medium introduction step: The heat source medium with heat is output from the low parameter heat source unit and the heat source medium is introduced into the heat pump temperature raising unit; The heat pump circulation heating step involves the heat pump heating unit absorbing and heating the heat source medium. Energy storage steps of thermal storage medium: During off-peak electricity periods, the heat in the heat pump heating unit is input into the thermal storage unit for storage; Release for power generation step: During peak power periods, the heat stored in the thermal storage unit is released to generate electricity.

10. The heat pump coupled energy storage peak-shaving method according to claim 9, characterized in that, It also includes the following steps: Dynamic control steps: Using the control unit, based on the acquired grid load demand, the operating parameters of the low-parameter heat source unit, the operating status of the heat pump heating unit, the heat storage status of the heat storage unit, and the output demand of the high-parameter power generation unit, the heat extraction valve's heat extraction from the heat source medium, the operating load of the heat pump heating unit, the heat charging and discharging power of the heat storage unit, and the heat received by the high-parameter power generation unit are adjusted.

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