Carnot battery system based on cross-seasonal energy storage technology and control method

Abstract

The invention discloses a Carnot battery system based on a cross-seasonal energy storage technology and a control method, and the Carnot battery system comprises a cascade heat pump unit, a buried pipe heat storage unit, an organic Rankine cycle unit and a renewable heat source utilization energy storage unit, when the temperature of the external environment is high in summer, heat exchange with the external environment can be conducted through the first heat removal and exchange module to provide a heat source for the second heat removal and exchange module, and heat exchange is conducted through the second heat removal and exchange module so that the temperature of a power generation fluid medium can be increased; when the external environment temperature is low in winter, a heat source can be provided for the second heat removal and exchange module through heat exchange between the first heat exchange module and the buried pipe heat storage unit, heat exchange is conducted through the second heat removal and exchange module so that the temperature of a power generation fluid medium can be increased, and the energy storage system is prevented from being affected by the external temperature; and high-efficiency operation in different seasons is ensured. The method provided by the invention solves the technical problem of low power generation efficiency in winter by utilizing environment heat exchange in the Carnot battery energy storage technology in the prior art.

Description

Technical Field

[0001] The present invention relates to the field of energy storage technology, and in particular to a Carnot battery system and a control method based on cross-seasonal energy storage technology. Background Art

[0002] At present, with the depletion of fossil energy and the increasingly serious environmental pollution problems, the proportion of renewable energy, mainly solar energy and wind energy, in the world's energy structure has steadily increased. At the same time, the intermittent and volatile nature of renewable energy generation poses a huge challenge to the power grid's absorption capacity. Energy storage technology can capture and store various forms of energy and release it to users when needed, playing a vital role in peak-to-valley shifting of power systems and renewable energy grid connection. Existing energy storage technologies, such as pumped storage, compressed air energy storage and electrochemical energy storage, are limited by specific geographical conditions and the influence of service life in actual application. Although the Carnot battery energy storage technology can solve the above problems well, its electrical conversion efficiency is low. Especially in winter, the heat pump system, as the core module of the Carnot battery energy storage system, is affected by the ambient temperature, and the heat pump energy efficiency is poor, which further reduces the electrical conversion efficiency of the Carnot battery system. The existence of the above problems seriously limits the promotion and application of the Carnot battery system.

[0003] In view of this, it is necessary to propose a Carnot battery system and control method based on cross-season energy storage technology to solve or at least partially solve the above technical problems. Summary of the invention

[0004] The main purpose of the present invention is to provide a Carnot battery system and control method based on cross-season energy storage technology, aiming to solve the technical problem of low winter power generation efficiency in the prior art Carnot battery energy storage technology using environmental heat exchange.

[0005] To achieve the above-mentioned purpose, the present invention provides a Carnot battery system based on cross-seasonal energy storage technology, including a cascade heat pump unit, a ground pipe heat storage unit, an organic Rankine cycle unit and a renewable heat source utilization energy storage unit, the input end of the organic Rankine cycle unit is arranged in parallel with the renewable heat source utilization energy storage unit, the output end of the organic Rankine cycle unit is arranged in parallel with the ground pipe heat storage unit for heat exchange, the first side of the cascade heat pump unit is connected in parallel to the ground pipe heat storage unit, and the second side of the cascade heat pump unit is connected in parallel to the renewable heat source utilization energy storage unit;

[0006] The cascade heat pump unit includes a first heat extraction and heat exchange module and a second heat extraction and heat exchange module. The first heat extraction and heat exchange module is used to collect heat from the external environment or the buried pipe heat storage unit and exchange heat with the second heat extraction and heat exchange module. The second heat extraction and heat exchange module is used to collect heat from the first heat extraction and heat exchange module and exchange heat with a renewable heat source energy storage unit. The renewable heat source energy storage unit is used to heat and increase the temperature of the power generation fluid medium at the input end of the organic Rankine cycle unit.

[0007] Further, the first heat extraction and heat exchange module includes a first condenser evaporator, a first compressor, a first regenerator, a first expansion valve, a first evaporator, a second expansion valve and a second evaporator 7, the first compressor, the first condenser evaporator, the first regenerator, the first expansion valve and the first evaporator are arranged in sequence and connected through a first pipeline, the first condenser evaporator is between the first compressor and the first regenerator, and the inlet and outlet ends of the low temperature side of the first condenser evaporator are respectively connected to the first pipeline;

[0008] The second pipeline is connected in parallel to the first pipeline, the first end of the second pipeline is communicated with the first pipeline and is located between the first regenerator and the first expansion valve, the second end of the second pipeline is communicated with the first pipeline and is located between the first evaporator and the first regenerator, the second expansion valve is arranged on the second pipeline, the second evaporator is located downstream of the second expansion valve, and the inlet end and the outlet end of the high temperature side of the second evaporator are respectively communicated with the second pipeline;

[0009] The inlet and outlet ends of the low temperature side of the second evaporator are respectively connected to the buried pipe heat storage unit.

[0010] Further, the second heat extraction and heat exchange module includes a second compressor, a heat exchanger, a second heat regenerator and a third expansion valve which are arranged in sequence and connected through a third pipeline;

[0011] The inlet end and the outlet end of the high temperature side of the first condenser evaporator are respectively connected to the first pipeline;

[0012] The heat exchanger is located between the second compressor and the second regenerator, the inlet and outlet of the low temperature side of the heat exchanger are respectively connected to the third pipeline, and the inlet and outlet of the high temperature side of the heat exchanger are respectively connected to the renewable heat source utilization energy storage unit.

[0013] Further, the organic Rankine cycle unit includes a power generation cycle module and a power generation cooling module;

[0014] The power generation circulation module includes an expander, a first heat exchanger, a first pump body and a second heat exchanger which are arranged in sequence and connected through a fourth pipeline. The inlet end and the outlet end of the high temperature side of the first heat exchanger are respectively connected to the fourth pipeline, and the inlet end and the outlet end of the low temperature side of the second heat exchanger are respectively connected to the fourth pipeline. The power generation cooling module includes a first valve, a second pump body and a cooling tower which are arranged in sequence and connected through a fifth pipeline. The inlet end and the outlet end of the low temperature side of the first heat exchanger are respectively connected to the fifth pipeline. The cooling tower is upstream of the first heat exchanger, and a second valve is connected in parallel outside the cooling tower.

[0015] Further, the renewable heat source utilizing energy storage unit comprises a first working fluid heating module and a second working fluid heating module, the first working fluid heating module comprises a first storage tank body, a third control valve, a second power pump body, a second storage tank body, a fourth control valve and a water pump which are sequentially arranged and sequentially connected through a sixth pipeline, the inlet end and the outlet end of the high temperature side of the second heat exchanger are respectively connected to the sixth pipeline, and the second heat exchanger is located between the water pump and the second storage tank body;

[0016] The second working fluid heating module is connected in parallel to the second storage tank body. The second working fluid heating module includes a power pump body three and a solar collector which are arranged in sequence and connected through a seventh pipeline. The water inlet and outlet ends of the seventh pipeline are respectively connected to the two ports of the second storage tank body.

[0017] Further, the underground pipe heat storage unit includes a heat exchange cooling module, a heat exchange heating module and an underground heat storage module, the heat exchange cooling module includes a valve switch 1 and a valve switch 2 which are arranged in sequence and connected through an eighth pipeline, two ends of the underground heat storage module are respectively connected to the eighth pipeline and the underground heat storage module is located between the valve switch 1 and the valve switch 2, and the underground heat storage module is located downstream of the valve switch 1;

[0018] The heat exchange and heating module includes a power pump body 1, a control valve 1 and a control valve 2 which are arranged in sequence and connected through a ninth pipeline. Both ends of the underground heat storage module are respectively connected to the ninth pipeline and the underground heat storage module is located between the control valve 2 and the control valve 1. The inlet and outlet ends of the low-temperature side of the second evaporator are respectively connected to the ninth pipeline. The second evaporator is located downstream of the power pump body 1, and the underground heat storage module is located upstream of the control valve 2.

[0019] The present invention also provides a Carnot battery control method based on cross-season energy storage technology, and the Carnot battery system based on cross-season energy storage technology includes:

[0020] Single power generation mode, if the temperature difference between the input temperature and the output temperature of the power generation medium fluid is not greater than the first threshold, the Carnot battery system based on the cross-season energy storage technology is controlled to be in a single power generation mode, and the fluid medium in the power generation cooling module is in a static state when in the single power generation mode;

[0021] Power generation-soil source condensation heat recovery mode, if the temperature difference between the input temperature and the output temperature of the power generation medium fluid is not greater than the first threshold, the Carnot battery system based on the cross-seasonal energy storage technology is controlled to be in the power generation-soil source condensation heat recovery mode, and the fluid medium in the power generation cooling module is heat exchanged through the first heat exchanger when in the power generation-soil source condensation heat recovery mode, and then the power generation waste heat is stored in the buried pipe heat storage unit;

[0022] Composite heating mode, the composite heating mode is an air solar heating mode that integrates the air source heating mode and the solar heating mode, or the composite heating mode is a soil solar heating mode that integrates the soil source heating mode and the solar heating mode, or the composite heating mode is a single air source heating mode, or the composite heating mode is a single soil source heating mode;

[0023] Among them, when in the air solar heating mode, the renewable heat source utilizes the first working fluid heating module of the energy storage unit to heat the fluid medium with solar energy, the first heat extraction and heat exchange module is used to collect heat from the external environment and exchange heat with the second heat extraction and heat exchange module, and the second heat extraction and heat exchange module is used to collect heat from the first heat extraction and heat exchange module and exchange heat with the fluid medium heated by the renewable heat source using the energy storage unit;

[0024] When in the soil solar heating mode, the renewable heat source utilizes the first working fluid heating module of the energy storage unit to heat the fluid medium with solar energy, the first heat extraction and heat exchange module is used to collect heat from the buried pipe heat storage unit and exchange heat with the second heat extraction and heat exchange module, and the second heat extraction and heat exchange module is used to collect heat from the first heat extraction and heat exchange module and exchange heat with the fluid medium heated by the renewable heat source using the energy storage unit;

[0025] When in single air source heating mode, the first heat extraction and heat exchange module is used to collect heat from the external environment and exchange heat with the second heat extraction and heat exchange module, and the second heat extraction and heat exchange module is used to collect heat from the first heat extraction and heat exchange module and exchange heat with the fluid medium of the energy storage unit to increase the temperature of the renewable heat source;

[0026] When in single soil source heating mode, the first heat extraction and heat exchange module is used to collect heat from the buried pipe heat storage unit and exchange heat with the second heat extraction and heat exchange module, and the second heat extraction and heat exchange module is used to collect heat from the first heat extraction and heat exchange module and use the fluid medium in the energy storage unit to heat up the renewable heat source.

[0027] Furthermore, when in the air solar heating mode or the soil solar heating mode, the temperature is controlled by using the dichotomy coarse adjustment and PI control fine adjustment to make the target fluid entering the second storage tank body within the ideal temperature range, specifically including the steps of:

[0028] S10, obtaining a current temperature difference between an output temperature of a target fluid and an ideal temperature based on a debugged water outlet temperature sensor;

[0029] S20, determining whether the current temperature difference is within a preset temperature difference range;

[0030] S31, if the current temperature difference is within the preset temperature difference range, the exhaust port pressure of the second compressor is obtained based on the debugging pressure sensor 1 as the ideal condensing pressure;

[0031] S32: If the current temperature difference is not within the preset temperature difference range, the high temperature medium saturation pressure P cse and the minimum condensation pressure of high temperature medium P cmin Determining an ideal condensing pressure until the current temperature difference is within a preset temperature difference range, wherein the high-temperature medium saturation pressure is the saturation pressure of the high-temperature working medium, and the high-temperature working medium is the fluid medium flowing through the second compressor;

[0032] S40, performing PI control on the condensing pressure based on the ideal condensing pressure and the current temperature difference to determine the target condensing pressure until the current temperature difference is within the ideal temperature difference range;

[0033] S50, based on the debugging pressure sensor 4, the air inlet pressure of the first compressor is obtained as the low-temperature medium evaporation pressure P of the low-temperature working medium. e ;

[0034] S60, using the formula:

[0035] T m ={[T c T e (η L -1)+ΔT m ] / (η H -1)} 0.5 +ΔT m / 2 calculates the intermediate temperature, where η H =T c C Pw m w (T wos -T wis ) / (T c W H -T e W H ), η L =T c1 [C Pw m w (T wos -T wis )-W H ] / (T c1 W L -T e WL ),

[0036] Among them, T m is the intermediate temperature, T c is the high temperature medium condensation temperature of the high temperature working medium, T e is the low-temperature evaporation temperature of the low-temperature working medium, η L is the thermodynamic perfection of the low-temperature heat pump, η H is the thermodynamic perfection of the high-temperature heat pump, ΔT m is the heat transfer temperature difference, C Pw is the constant pressure specific heat capacity of the fluid medium, m w is the flow rate of the target fluid, T wos is the ideal temperature of the target fluid, T wi is the inlet temperature of the target fluid, W H is the compression power consumption of the high temperature heat pump, W L is the compression power consumption of the low-temperature heat pump, where the high-temperature medium condensation temperature T c Corresponding to the target condensing pressure, the low temperature medium evaporation temperature T e and low temperature medium evaporation pressure P e Corresponding; wherein the low temperature working medium is the fluid medium flowing through the first compressor;

[0037] S70, adjusting the expansion valve of the second compressor in the high-temperature stage heat pump system according to the intermediate temperature.

[0038] Compared with the prior art, the Carnot battery system based on the cross-season energy storage technology provided by the present invention has the following beneficial effects:

[0039] A Carnot battery system based on cross-seasonal energy storage technology provided by the present invention includes a cascade heat pump unit, a buried pipe heat storage unit, an organic Rankine cycle unit and a renewable heat source utilization energy storage unit. The high temperature side of the renewable heat source utilization energy storage unit is used to exchange heat with the input end of the organic Rankine cycle unit to increase the temperature of the power generation fluid medium, and the heat collection side of the buried pipe heat storage unit is used to exchange heat with the output end of the organic Rankine cycle unit to reduce the temperature of the power generation fluid medium, thereby facilitating the improvement of the temperature difference between the input end and the output end of the organic Rankine cycle unit to ensure the power generation efficiency; the cascade heat pump unit includes a first heat extraction and heat exchange module and a second heat extraction and heat exchange module, the first heat extraction and heat exchange module is used to collect the external environment or the buried pipe heat storage unit The heat of the first heat taking and heat exchanging module is exchanged with the second heat taking and heat exchanging module, and the second heat taking and heat exchanging module is used to collect the heat of the first heat taking and heat exchanging module and exchange heat with the renewable heat source using the energy storage unit. In summer, when the external ambient temperature is high, the first heat taking and heat exchanging module can be used to exchange heat with the external environment to provide a heat source for the second heat taking and heat exchanging module, and the heat exchange through the second heat taking and heat exchanging module is used to heat up the power generation fluid medium. In winter, when the external ambient temperature is low, the first heat exchanging module can be used to exchange heat with the buried pipe heat storage unit to provide a heat source for the second heat taking and heat exchanging module, and the heat exchange through the second heat taking and heat exchanging module is used to heat up the power generation fluid medium, thereby avoiding the energy storage system from being affected by the external temperature and ensuring its efficient operation at all times in different seasons. In summer and transition seasons, the soil temperature is low and the temperature difference with the external environment is large. During the power generation process of the organic Rankine cycle unit, the temperature of the power generation medium fluid passing through the expander is high, and there is waste heat at the first heat exchanger that cannot be fully utilized. At this time, the waste heat of the power generation medium fluid passing through the expander is stored in the buried pipe heat storage unit through the first heat exchanger. In winter, the external environment temperature is low. During the power generation process of the organic Rankine cycle unit, the temperature of the power generation medium fluid passing through the expander is low. The efficiency of the organic Rankine cycle module increases as the external temperature decreases. At this time, the power generation cycle module and the power generation cooling module can be isolated to ensure power generation efficiency. In addition, the energy efficiency of the cascade heat pump decreases as the external temperature decreases. Therefore, in winter, the soil source heat can be used to utilize the waste heat stored in the summer and transition seasons. At this time, the cascade heat pump unit and the buried pipe heat storage unit exchange heat. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0041] Figure 1This is one of the structural schematic diagrams of a Carnot battery system based on cross-seasonal energy storage technology in one embodiment of the present invention;

[0042] Figure 2 This is a second structural schematic diagram of a Carnot battery system based on cross-seasonal energy storage technology in one embodiment of the present invention;

[0043] Figure 3 This is a third structural schematic diagram of a Carnot battery system based on cross-seasonal energy storage technology in one embodiment of the present invention;

[0044] Figure 4 Schematic diagram of the system principle corresponding to the Carnot battery system control method based on cross-season energy storage technology in one embodiment of the present invention.

[0045] Legend:

[0046] 100. Cascade heat pump unit; 11. First heat extraction and heat exchange module; 12. Second heat extraction and heat exchange module;

[0047] 111, first condenser evaporator; 112, first compressor; 113, first regenerator; 114, first expansion valve; 115, first evaporator; 116, second expansion valve; 117, second evaporator; 118, first pipeline; 119, second pipeline;

[0048] 121, third pipeline; 122, second compressor; 123, heat exchanger; 124, second regenerator; 125, third expansion valve;

[0049] 200, underground pipe heat storage unit; 21, heat exchange and cooling module; 211, eighth pipeline; 212, valve switch 1 212; 213, valve switch 2 213;

[0050] 22. Heat exchange and heating module; 221. Ninth pipeline; 222. Power pump body 1; 223. Control valve 1; 224. Control valve 2;

[0051] 23. Underground heat storage module;

[0052] 300. Organic Rankine cycle unit; 31. Power generation cycle module; 32. Power generation cooling module;

[0053] 311, fourth pipeline; 312, expander; 313, first heat exchanger; 314, first pump body; 315, second heat exchanger;

[0054] 321, fifth pipeline; 322, first valve; 323, second pump body; 324, cooling tower; 325, second valve;

[0055] 400. Renewable heat source utilizing energy storage unit; 41. First working fluid heating module; 42. Second working fluid heating module;

[0056] 411, sixth pipeline; 412, first storage tank; 413, control valve three; 414, power pump body two; 415, second storage tank; 416, control valve four; 417, water pump;

[0057] 421. Pipeline No. 7; 422. Power pump body No. 3; 423. Solar collector;

[0058] 1001. Debug the outlet water temperature sensor; 1002. Debug the pressure sensor 1; 1003. Debug the pressure sensor 2; 1004. Debug the pressure sensor 3; 1005. Debug the pressure sensor 4; 1006. Debug the water flow sensor; 1007. Debug the inlet water temperature sensor.

[0059] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0060] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0061] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0063] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0064] Please refer to Figure 1 , Figure 2 and Figure 3 The present invention provides a Carnot battery system based on cross-seasonal energy storage technology, including a cascade heat pump unit 100, a ground pipe heat storage unit 200, an organic Rankine cycle unit 300, and a renewable heat source utilization energy storage unit 400. The input end of the organic Rankine cycle unit 300 is connected in parallel with the renewable heat source utilization energy storage unit 400, and the output end of the organic Rankine cycle unit 300 is connected in parallel with the ground pipe heat storage unit 200 for heat exchange. The first side of the cascade heat pump unit 100 is connected in parallel to the ground pipe heat storage unit 200, and the second side of the cascade heat pump unit 100 is connected in parallel to the renewable heat source utilization energy storage unit 400. 00, the cascade heat pump unit 100 includes a first heat extraction and heat exchange module 11 and a second heat extraction and heat exchange module 12. The first heat extraction and heat exchange module 11 is used to collect heat from the external environment and / or the buried pipe heat storage unit 200 (heat exchanger 1231) and exchange heat with the second heat extraction and heat exchange module 12. The second heat extraction and heat exchange module 12 is used to collect heat from the first heat extraction and heat exchange module 11 and exchange heat with the renewable heat source utilization energy storage unit 400 (water-cooled heat exchanger 123). The renewable heat source utilization energy storage unit 400 is used to heat and increase the temperature of the power generation fluid medium at the input end of the organic Rankine cycle unit 300.

[0065] A Carnot battery system based on cross-seasonal energy storage technology provided by the present invention includes a cascade heat pump unit 100, a buried pipe heat storage unit 200, an organic Rankine cycle unit 300 and a renewable heat source utilization energy storage unit 400. The high temperature side of the renewable heat source utilization energy storage unit 400 is used to exchange heat with the input end of the organic Rankine cycle unit 300 to increase the temperature of the power generation fluid medium, and the heat collection side of the buried pipe heat storage unit 200 is used to exchange heat with the output end of the organic Rankine cycle unit 300 to reduce the temperature of the power generation fluid medium, thereby facilitating the improvement of the temperature difference between the input end and the output end of the organic Rankine cycle unit 300 to ensure the power generation efficiency; the cascade heat pump unit 100 includes a first heat extraction heat exchange module 11 and a second heat extraction heat exchange module 12, and the first heat extraction heat exchange module 11 is used to collect the external environment or the ground The heat of the buried pipe heat storage unit 200 is exchanged with the second heat extraction and heat exchange module 12. The second heat extraction and heat exchange module 12 is used to collect the heat of the first heat extraction and heat exchange module 11 and exchange heat with the renewable heat source using the energy storage unit 400. In the summer, when the external ambient temperature is high, the first heat extraction and heat exchange module 11 can exchange heat with the external environment to provide a heat source for the second heat extraction and heat exchange module 12, and the second heat extraction and heat exchange module 12 can be used to exchange heat for heating the power generation fluid medium. In the winter, when the external ambient temperature is low, the first heat exchange module can exchange heat with the buried pipe heat storage unit 200 to provide a heat source for the second heat extraction and heat exchange module 12, and the second heat extraction and heat exchange module 12 can be used to heat the power generation fluid medium, thereby avoiding the energy storage system from being affected by the external temperature and ensuring that it always operates efficiently in different seasons. In summer and transition seasons, the soil temperature is low and the temperature difference with the external environment is large. During the power generation process of the organic Rankine cycle unit 300, the temperature of the power generation medium fluid passing through the expander 312 is high, and there is waste heat at the first heat exchanger 313 that cannot be fully utilized. At this time, the waste heat of the power generation medium fluid passing through the expander 312 is stored in the buried pipe heat storage unit 200 through the first heat exchanger 313. In winter, the external environment temperature is low. During the power generation process of the organic Rankine cycle unit 300, the temperature of the power generation medium fluid passing through the expander 312 is low. The efficiency of the organic Rankine cycle module increases as the external temperature decreases. At this time, the power generation cycle module 31 and the power generation cooling module 32 can be isolated to ensure the power generation efficiency. In addition, the energy efficiency of the cascade heat pump decreases as the external temperature decreases. Therefore, in winter, the soil source heat can be used to utilize the waste heat stored in the summer and transition seasons. At this time, the cascade heat pump unit 100 and the buried pipe heat storage unit 200 perform heat exchange.

[0066] It can be understood that in summer and transition seasons, the external environment temperature is high, the soil temperature is low and the temperature difference with the external environment is large, and the first heat extraction and heat exchange module 11 can be used to exchange heat with the external environment to provide a heat source for the second heat exchange module. The second heat exchange module is used to make the renewable heat source use the fluid medium of the energy storage unit 400 to heat up, and the renewable heat source uses the fluid medium of the energy storage unit 400 to exchange heat with the power generation medium fluid to heat it up. In the power generation process of the organic Rankine cycle unit 300, the temperature of the power generation medium fluid passing through the expander 312 is relatively high, and there is waste heat at the first heat exchanger 313 that cannot be fully utilized. At this time, The first heat exchanger 313 stores the waste heat of the power generation medium fluid passing through the expander 312 in the buried pipe heat storage unit 200; in winter, the external environment temperature is low, and the first heat extraction and heat exchange module 11 can exchange heat with the buried pipe heat storage unit 200 to provide a heat source for the second heat exchange module, and the second heat exchange module is used to heat the power generation medium fluid, and during the power generation process of the organic Rankine cycle unit 300, the temperature of the power generation medium fluid passing through the expander 312 is low, and the efficiency of the organic Rankine cycle module increases as the external temperature decreases. At this time, the power generation cycle module 31 and the power generation cooling module 32 can be isolated to ensure the power generation efficiency. In addition, the energy efficiency of the cascade heat pump decreases as the external temperature decreases. Therefore, in winter, the soil source heat can be used to utilize the waste heat stored in the summer and transition seasons. At this time, the cascade heat pump unit 100 and the buried pipe heat storage unit 200 perform heat exchange.

[0067] It can be understood that the renewable heat source utilizes the energy storage unit 400 including a first working fluid heating module 41 and a second working fluid heating module 42. The first working fluid heating module 41 includes a second storage tank body 415. The second storage tank body 415 can store the fluid medium that has reached the target temperature and then, when necessary, pass the fluid medium that has reached the target temperature through the second heat exchanger 315 to heat the power generation fluid medium.

[0068] Furthermore, the first heat extraction and heat exchange module 11 includes a first condenser evaporator 111, a first compressor 112, a first regenerator 113, a first expansion valve 114, a first evaporator 115, a second expansion valve 116 and a second evaporator 117. The first compressor 112, the first condenser evaporator 111, the first regenerator 113, the first expansion valve 114 and the first evaporator 115 are arranged in sequence and connected through a first pipeline 118. The first condenser evaporator 111 is located between the first compressor 112 and the first regenerator 113. The inlet and outlet ends of the low temperature side of the first condenser evaporator 111 are respectively connected to the first pipeline 118. The pipeline 119 is connected in parallel to the first pipeline 118, the first end of the second pipeline 119 is connected to the first pipeline 118 and is located between the first heat regenerator 113 and the first expansion valve 114, the second end of the second pipeline 119 is connected to the first pipeline 118 and is located between the first evaporator 115 and the first heat regenerator 113, the second expansion valve 116 is arranged on the second pipeline 119, the second evaporator 117 is located downstream of the second expansion valve 116 and the inlet and outlet ends of the high temperature side of the second evaporator 117 are respectively connected to the second pipeline 119, and the inlet and outlet ends of the low temperature side of the second evaporator 117 are respectively connected to the buried pipe heat storage unit 200.

[0069] Furthermore, the second heat extraction and heat exchange module 12 includes a second compressor 122, a heat exchanger 123, a second heat regenerator 124 and a third expansion valve 125 which are arranged in sequence and connected through a third pipe 121. The inlet and outlet ends of the high temperature side of the first condenser evaporator 111 are respectively connected to the first pipe 118, the heat exchanger 123 is located between the second compressor and the second heat regenerator 124, the inlet and outlet ends of the low temperature side of the heat exchanger 123 are respectively connected to the third pipe 121, and the inlet and outlet ends of the high temperature side of the heat exchanger 123 are respectively connected to the renewable heat source utilization energy storage unit 400.

[0070] Furthermore, the organic Rankine cycle unit 300 includes a power generation cycle module 31 and a power generation cooling module 32. The power generation cycle module 31 includes an expander 312, a first heat exchanger 313, a first pump body 314 and a second heat exchanger 315 which are arranged in sequence and connected through a fourth pipe 311. The inlet end and the outlet end of the high temperature side of the first heat exchanger 313 are respectively connected to the fourth pipe 311, and the inlet end and the outlet end of the low temperature side of the second heat exchanger 315 are respectively connected to the fourth pipe 311. The power generation cooling module 32 includes a first valve 322, a second pump body 323 and a cooling tower 324 which are arranged in sequence and connected through a fifth pipe 321. The inlet end and the outlet end of the low temperature side of the first heat exchanger 313 are respectively connected to the fifth pipe 321. The cooling tower 324 is upstream of the first heat exchanger 313, and a second valve 325 is connected in parallel to the cooling tower 324.

[0071] Furthermore, the renewable heat source utilizes the energy storage unit 400 including a first working fluid heating module 41 and a second working fluid heating module 42. The first working fluid heating module 41 includes a first storage tank body 412, a control valve three 413, a power pump body two 414, a second storage tank body 415, a control valve four 416 and a water pump 417 which are arranged in sequence and connected in sequence through a sixth pipeline 411. The inlet and outlet ends of the high temperature side of the second heat exchanger 315 are respectively connected to the sixth pipeline 411, and the second heat exchanger is located between the water pump 417 and the second storage tank body 415; the second working fluid heating module 42 is connected in parallel to the second storage tank body 415, and the second working fluid heating module 42 includes a power pump body three 422 and a solar collector 423 which are arranged in sequence and connected through a seventh pipeline 421, and the water inlet and outlet ends of the seventh pipeline 421 are respectively connected to the two ports of the second storage tank body 415.

[0072] It can be understood that the second working fluid heating module 42 is used to use solar energy to initially heat the fluid medium, and the second working fluid heating module 42 is used to exchange heat with the second heat extraction and heat exchange module 12 to perform secondary heating of the fluid medium, thereby facilitating the fluid medium to reach the target temperature and be stored in the second storage tank body 415.

[0073] Furthermore, the underground heat storage unit 200 includes a heat exchange cooling module 21, a heat exchange heating module 22 and an underground heat storage module 23. The heat exchange cooling module 21 includes a valve switch 1 212 and a valve switch 2 213 which are arranged in sequence and connected through an eighth pipeline 211. Both ends of the underground heat storage module 23 are respectively connected to the eighth pipeline 211 and the underground heat storage module 23 is located between the valve switch 1 212 and the valve switch 2 213. The underground heat storage module 23 is located downstream of the valve switch 1 212. The heat exchange heating module 22 includes a valve switch 1 212 and a valve switch 2 213 which are arranged in sequence and connected through an eighth pipeline 211. It includes a power pump body 1 222, a control valve 1 223 and a control valve 2 224 which are arranged in sequence and connected through a ninth pipeline 221. Both ends of the underground heat storage module 23 are respectively connected to the ninth pipeline 221 and the underground heat storage module 23 is located between the control valve 224 and the control valve 1 223. The inlet and outlet ends of the low temperature side of the second evaporator 117 are respectively connected to the ninth pipeline 221. The second evaporator 117 is located downstream of the power pump body 1 222, and the underground heat storage module 23 is located upstream of the control valve 224.

[0074] It can be understood that in the present invention, the renewable heat source utilizes the energy storage unit 400 to utilize the renewable energy. The renewable energy provides clean electricity, but its randomness and volatility increase the uncertainty of the power grid. Therefore, in this context, the Carnot battery system based on the cross-seasonal energy storage technology is the key to promoting better integration of energy resources and overcoming its volatility. By adding the cascade heat pump unit 100 for transition, it is convenient to overcome the impact of renewable energy fluctuations.

[0075] Understandably, due to the high temperature in summer and the low temperature in winter, the change in air temperature leads to unstable heat exchange of the working fluid during the heat pump cycle, affecting the subsequent work of the compressor and further affecting the charging efficiency of the energy storage system.

[0076] Please refer to Figure 4 Furthermore, the Carnot battery system based on the cross-seasonal energy storage technology also includes a debugging water outlet temperature sensor 1001, a debugging pressure sensor 1 1002, a debugging pressure sensor 2 1003, a debugging pressure sensor 3 1004, a debugging pressure sensor 4 1005, a debugging water flow sensor 1006, and a debugging water inlet temperature sensor 1007. The debugging water inlet temperature sensor 1007 and the debugging water flow sensor 1006 are both arranged on the input side of the high temperature side of the heat exchanger 123, and the debugging water outlet temperature sensor 1001 is arranged on the output side of the high temperature side of the heat exchanger 123; the debugging pressure sensor 1 1002 is arranged on the output side of the low temperature side of the heat exchanger 123, and the debugging pressure sensor 2 1003 is arranged on the input side of the second compressor 122; the debugging pressure sensor 3 1004 is arranged on the output side of the low temperature side of the first condenser evaporator 111, and the debugging pressure sensor 4 1005 is arranged on the input side of the low temperature side of the first condenser evaporator 111.

[0077] In specific implementation, the debugging water inlet temperature sensor 1007 is arranged upstream of the control valve three 413 , and the debugging water flow sensor 1006 is arranged downstream of the power pump body two 414 .

[0078] The high temperature input pressure sensor is disposed upstream of the high temperature system compressor 23 , and the high temperature output pressure sensor is disposed downstream of the high temperature system compressor 23 .

[0079] Furthermore, the present invention also provides a Carnot battery control method based on cross-season energy storage technology, which is used for the above-mentioned Carnot battery system based on cross-season energy storage technology. When it is in air solar heating mode or soil solar heating mode, the temperature is controlled by using dichotomy coarse adjustment and PI control fine adjustment to make the target fluid entering the second storage tank body 415 within the ideal temperature range, which specifically includes the steps of:

[0080] S10, obtaining the current temperature difference between the output temperature of the target fluid and the ideal temperature based on the debugging of the outlet water temperature sensor 1001; specifically, the target fluid is the fluid medium stored in the second storage tank 415, and the output temperature of the fluid medium is obtained by debugging the outlet water temperature sensor 1001;

[0081] S20, determining whether the current temperature difference is within a preset temperature difference range;

[0082] S31, if the current temperature difference is within the preset temperature difference range, the exhaust port pressure of the second compressor 122 is obtained as the ideal condensing pressure based on the debugging pressure sensor 1002; specifically, if the current temperature difference is within the preset temperature difference range, the current working condensing pressure in the high temperature heat pump system is obtained as the ideal condensing pressure, that is, the current working condensing pressure in the high temperature heat pump system is obtained as the ideal condensing pressure;

[0083] S32: If the current temperature difference is not within the preset temperature difference range, the high temperature medium saturation pressure P cse and the minimum condensation pressure of high temperature medium P cmin Determine the ideal condensing pressure until the current temperature difference is within the preset temperature difference range; specifically, the high-temperature medium saturation pressure is the saturation pressure of the high-temperature working medium, the high-temperature medium minimum condensing pressure is the minimum condensing pressure of the high-temperature working medium, and the high-temperature working medium is the fluid medium flowing through the second compressor 122 (high-temperature stage heat pump system);

[0084] S40, performing PI control on the condensing pressure based on the ideal condensing pressure and the current temperature difference to determine the target condensing pressure until the current temperature difference is within the ideal temperature difference range;

[0085] S50, S50, based on the debugging pressure sensor 4 1005, the air inlet pressure of the first compressor 112 is obtained as the low-temperature medium evaporation pressure P of the low-temperature working medium. e Specifically, the low-temperature medium evaporation pressure P of the low-temperature working medium in the low-temperature heat pump system is determined according to the current ambient temperature of the low-temperature heat pump system. e , the low-temperature working medium is the fluid medium flowing through the first compressor 112 (low-temperature stage heat pump system);

[0086] S60, using the formula:

[0087] T m ={[T c T e (η L -1)+ΔT m ] / (η H -1)} 0.5 +ΔT m / 2 calculates the intermediate temperature, where η H =T c C Pw m w (T wos -T wis ) / (T c W H -T e W H ), η L =T c1 [C Pw mw (T wos -T wis )-W H ] / (T c1 W L -T e W L ),

[0088] Among them, T m is the intermediate temperature, T c is the high temperature medium condensation temperature of the high temperature working medium, T e is the low-temperature evaporation temperature of the low-temperature working medium, η L is the thermodynamic perfection of the low-temperature heat pump, η H is the thermodynamic perfection of the high-temperature heat pump, ΔT m is the heat transfer temperature difference, C Pw is the constant pressure specific heat capacity of the fluid medium, m w is the flow rate of the target fluid, T wos is the ideal temperature of the target fluid, T wi is the inlet temperature of the target fluid, W H is the compression power consumption of the high temperature heat pump, W L is the compression power consumption of the low-temperature heat pump, where the high-temperature medium condensation temperature T c Corresponding to the target condensing pressure, the low temperature medium evaporation temperature T e and low temperature medium evaporation pressure P e Corresponding; specifically, T m is the temperature at the first condenser evaporator position, T c is the temperature at the heat exchanger 123, which is obtained by converting the pressure sensor 1002. w Obtained by debugging flow sensor 1007;

[0089] S70, adjusting the expansion valve of the second compressor 122 in the high-temperature stage heat pump system according to the intermediate temperature.

[0090] In specific implementation, step S32 specifically includes:

[0091] S321, if the current temperature difference is within the preset temperature difference range, obtain the high-temperature medium saturation pressure P of the high-temperature working medium in the high-temperature heat pump system cse (compressor exhaust pressure of the second compressor 122), obtain the minimum condensing pressure P of the high-temperature working medium in the high-temperature heat pump system cmin (compressor discharge pressure of the second compressor 122);

[0092] S322, using formula P cset =(P cmin +P cse) / 2Get the current initial value of condensing pressure P cset ;

[0093] S323, determine the current initial value P of the condensing pressure cset Check whether the current temperature difference is within the preset temperature difference range;

[0094] S324, if the condensing pressure is currently set to an initial value P cset If the current temperature difference is within the preset temperature difference range, the current condensing pressure setting initial value P is determined. cset is the ideal condensing pressure;

[0095] S325, if the current condensing pressure is set to an initial value P cset If the current temperature difference is not within the preset temperature difference range, the current condensing pressure is set to the initial value P. cset Check whether the current outlet water temperature is higher than the ideal temperature.

[0096] S326, if the current condensing pressure is set to an initial value P cset If the current outlet water temperature is higher than the ideal temperature, the current condensing pressure is set to the initial value P cset Updated to high temperature medium saturation pressure P cse , and enter step S32 based on the minimum condensation pressure P of the high temperature medium cmin And the updated high temperature medium saturation pressure P cse Re-obtain the current initial value P of the condensing pressure cset ;

[0097] S327, if the current condensing pressure is set to an initial value P cset When the current outlet water temperature is lower than the ideal temperature, the current condensing pressure is set to the initial value P cset Updated to the minimum condensing pressure P of low temperature medium cmin , and enter step S32 based on the high temperature medium saturation pressure P cse And the updated minimum condensing pressure P of high temperature medium cmin Re-obtain the current initial value P of the condensing pressure cset ;

[0098] Repeat steps S322 to S325 until the ideal condensing pressure is obtained.

[0099] In specific implementation, the formula m is used rc =C Pw m w (T wos -T wis ) / (h co1 -h ci1 ) Calculate the refrigerant flow rate of the high-temperature working medium in the high-temperature heat pump system,

[0100] Using the formula ΔTN =m rc (h cG1 -h cL1 ) / C Pw m w +T wi -T c1 Calculate the temperature difference at the narrow point and obtain ΔT N =0 when the assumed condensation temperature T c1 , and then determine the assumed condensation pressure P c1 is the minimum condensation temperature of high temperature medium T cmin ,

[0101] Among them, m rc is the refrigerant flow rate, ΔT N is the narrow point temperature difference, C Pw is the constant pressure specific heat capacity of the fluid, m w is the flow rate of the target fluid, T wos is the ideal temperature of the target fluid, T wis is the inlet temperature of the target fluid, h co1 is the target condenser outlet enthalpy, h ci1 is the target condenser inlet enthalpy, h cG1 is the enthalpy of the refrigerant at the bubble point of the high-temperature condenser, h cL1 is the enthalpy of the refrigerant at the high-temperature condenser outlet,

[0102] According to the refrigerant physical property model, the minimum condensation temperature T of the high temperature medium is obtained. cmin The corresponding minimum condensation pressure of high temperature medium P cmin .

[0103] According to the method of the present invention, the outlet water temperature control mode relies on cascade control. After the current temperature difference is roughly adjusted to be within the preset temperature difference range, fine adjustment is adopted to further make the current temperature difference within the ideal temperature difference range. The physical mechanism rough adjustment is combined with the PI control fine adjustment, which has strong robustness, fast response speed and strong anti-interference ability. The low-temperature medium evaporation pressure is determined based on the physical mechanism, so that the heat pump can be accurately and efficiently heat extracted and multiple operating parameters can be decoupled. The intermediate temperature is obtained by online collection of operating data, identifying model parameters, and outputting the optimal intermediate temperature based on the physical model, taking into account both model accuracy and interpretability. The intermediate temperature is obtained based on the high-temperature medium condensation temperature and the low-temperature medium evaporation temperature, and the expansion valve of the second compressor is adjusted according to the intermediate temperature, so that the high-temperature medium condensation temperature and the low-temperature medium evaporation temperature can directly adjust the expansion valve of the second compressor. The technical problem of easily causing overshoot and oscillation in the temperature control process in the prior art is solved.

[0104] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A Carnot battery system based on cross-season energy storage technology, characterized in that: It comprises a cascade heat pump unit, a ground pipe heat storage unit, an organic Rankine cycle unit and a renewable heat source utilization energy storage unit, wherein the renewable heat source utilization energy storage unit is arranged in parallel at the input end of the organic Rankine cycle unit, the ground pipe heat storage unit is arranged in parallel at the output end of the organic Rankine cycle unit for heat exchange, the first side of the cascade heat pump unit is connected in parallel to the ground pipe heat storage unit, and the second side of the cascade heat pump unit is connected in parallel to the renewable heat source utilization energy storage unit; The cascade heat pump unit includes a first heat extraction and heat exchange module and a second heat extraction and heat exchange module. The first heat extraction and heat exchange module is used to collect heat from the external environment or the buried pipe heat storage unit and exchange heat with the second heat extraction and heat exchange module. The second heat extraction and heat exchange module is used to collect heat from the first heat extraction and heat exchange module and exchange heat with the renewable heat source utilizing energy storage unit. The renewable heat source utilizing energy storage unit is used to heat and increase the temperature of the power generation fluid medium at the input end of the organic Rankine cycle unit.

2. The Carnot battery system based on cross-season energy storage technology according to claim 1 is characterized in that: The first heat extraction and heat exchange module comprises a first condenser evaporator, a first compressor, a first regenerator, a first expansion valve, a first evaporator, a second expansion valve and a second evaporator 7, wherein the first compressor, the first condenser evaporator, the first regenerator, the first expansion valve and the first evaporator are arranged in sequence and connected through a first pipeline, wherein the first condenser evaporator is located between the first compressor and the first regenerator, and an inlet end and an outlet end of a low temperature side of the first condenser evaporator are respectively connected to the first pipeline; The second pipeline is connected in parallel to the first pipeline, the first end of the second pipeline is communicated with the first pipeline and is located between the first regenerator and the first expansion valve, the second end of the second pipeline is communicated with the first pipeline and is located between the first evaporator and the first regenerator, the second expansion valve is arranged on the second pipeline, the second evaporator is located downstream of the second expansion valve, and the inlet end and the outlet end of the high temperature side of the second evaporator are respectively communicated with the second pipeline; The inlet and outlet ends of the low temperature side of the second evaporator are respectively connected to the buried pipe heat storage unit.

3. The Carnot battery system based on cross-season energy storage technology according to claim 2 is characterized in that: The second heat extraction and heat exchange module includes a second compressor, a heat exchanger, a second heat regenerator and a third expansion valve which are arranged in sequence and connected through a third pipeline. The inlet end and the outlet end of the high temperature side of the first condenser evaporator are respectively connected to the first pipeline; The heat exchanger is located between the second compressor and the second regenerator, the inlet and outlet ends of the low temperature side of the heat exchanger are respectively connected to the third pipeline, and the inlet and outlet ends of the high temperature side of the heat exchanger are respectively connected to the renewable heat source utilization energy storage unit.

4. The Carnot battery system based on cross-season energy storage technology according to any one of claims 1 to 3, characterized in that: The organic Rankine cycle unit includes a power generation cycle module and a power generation cooling module; The power generation circulation module includes an expander, a first heat exchanger, a first pump body and a second heat exchanger which are arranged in sequence and connected through a fourth pipeline. The inlet end and the outlet end of the high temperature side of the first heat exchanger are respectively connected to the fourth pipeline, and the inlet end and the outlet end of the low temperature side of the second heat exchanger are respectively connected to the fourth pipeline. The power generation cooling module includes a first valve, a second pump body and a cooling tower which are arranged in sequence and connected through a fifth pipeline. The inlet end and the outlet end of the low temperature side of the first heat exchanger are respectively connected to the fifth pipeline. The cooling tower is upstream of the first heat exchanger, and a second valve is connected in parallel outside the cooling tower.

5. The Carnot battery system based on cross-season energy storage technology according to any one of claims 1 to 3, characterized in that: The renewable heat source utilizing energy storage unit comprises a first working fluid heating module and a second working fluid heating module, the first working fluid heating module comprises a first storage tank body, a third control valve, a second power pump body, a second storage tank body, a fourth control valve and a water pump which are sequentially arranged and sequentially connected through a sixth pipeline, the inlet end and the outlet end of the high temperature side of the second heat exchanger are respectively connected to the sixth pipeline, and the second heat exchanger is located between the water pump and the second storage tank body; The second working fluid heating module is connected in parallel to the second storage tank body. The second working fluid heating module includes a power pump body three and a solar collector arranged in sequence and connected through a seventh pipeline. The water inlet and outlet ends of the seventh pipeline are respectively connected to the two ports of the second storage tank body.

6. The Carnot battery system based on cross-season energy storage technology according to any one of claims 1 to 3, characterized in that: The underground heat storage unit includes a heat exchange cooling module, a heat exchange heating module and an underground heat storage module. The heat exchange cooling module includes a valve switch 1 and a valve switch 2 which are arranged in sequence and connected through an eighth pipeline. Both ends of the underground heat storage module are connected to the eighth pipeline respectively and the underground heat storage module is located between the valve switch 1 and the valve switch 2. The underground heat storage module is located downstream of the valve switch 1. The heat exchange and heating module includes a power pump body 1, a control valve 1 and a control valve 2 which are arranged in sequence and connected through a ninth pipeline. Both ends of the underground heat storage module are respectively connected to the ninth pipeline and the underground heat storage module is located between the control valve 2 and the control valve 1. The inlet and outlet ends of the low temperature side of the second evaporator are respectively connected to the ninth pipeline. The second evaporator is located downstream of the power pump body 1, and the underground heat storage module is located upstream of the control valve 2.

7. A Carnot battery control method based on cross-season energy storage technology, used in a Carnot battery system based on cross-season energy storage technology as claimed in any one of claims 1 to 6, characterized in that: include Single power generation mode, if the temperature difference between the input temperature and the output temperature of the power generation medium fluid is not greater than the first threshold, the Carnot battery system based on the cross-seasonal energy storage technology is controlled to be in a single power generation mode, and the fluid medium in the power generation cooling module is in a static state when in the single power generation mode; Power generation-soil source condensation heat recovery mode, if the temperature difference between the input temperature and the output temperature of the power generation medium fluid is not greater than the first threshold, the Carnot battery system based on the cross-seasonal energy storage technology is controlled to be in the power generation-soil source condensation heat recovery mode, and when in the power generation-soil source condensation heat recovery mode, the fluid medium in the power generation cooling module is heat exchanged through the first heat exchanger, and then the power generation waste heat is stored in the buried pipe heat storage unit; A composite heating mode, wherein the composite heating mode is an air-solar heating mode that is a fusion of an air-source heating mode and a solar-energy heating mode, or the composite heating mode is a soil-solar heating mode that is a fusion of a soil-source heating mode and a solar-energy heating mode, or the composite heating mode is a single air-source heating mode, or the composite heating mode is a single soil-source heating mode; Wherein, when in the air solar heating mode, the renewable heat source utilizes the first working fluid heating module of the energy storage unit to utilize solar energy to heat the fluid medium, the first heat extraction and heat exchange module is used to collect heat from the external environment and exchange heat with the second heat extraction and heat exchange module, and the second heat extraction and heat exchange module is used to collect heat from the first heat extraction and heat exchange module and exchange heat with the fluid medium heated by the renewable heat source using the energy storage unit; When in the soil solar heating mode, the renewable heat source utilizes the first working fluid heating module of the energy storage unit to utilize solar energy to heat and raise the temperature of the fluid medium, the first heat extraction and heat exchange module is used to collect heat from the buried pipe heat storage unit and exchange heat with the second heat extraction and heat exchange module, and the second heat extraction and heat exchange module is used to collect heat from the first heat extraction and heat exchange module and exchange heat with the fluid medium heated by the renewable heat source using the energy storage unit.

8. The Carnot battery control method based on cross-season energy storage technology according to claim 7 is characterized in that: When in single air source heating mode, the first heat extraction and heat exchange module is used to collect heat from the external environment and exchange heat with the second heat extraction and heat exchange module, and the second heat extraction and heat exchange module is used to collect heat from the first heat extraction and heat exchange module and exchange heat with the fluid medium of the energy storage unit of the renewable heat source to increase the temperature; When in single soil source heating mode, the first heat extraction and heat exchange module is used to collect heat from the buried pipe heat storage unit and exchange heat with the second heat extraction and heat exchange module, and the second heat extraction and heat exchange module is used to collect heat from the first heat extraction and heat exchange module and heat the renewable heat source using the fluid medium in the energy storage unit to increase the temperature.

9. The Carnot battery control method based on cross-season energy storage technology according to claim 8 is characterized in that: When in the air solar heating mode or the soil solar heating mode, the temperature is controlled by using the dichotomy rough adjustment and PI control fine adjustment to make the target fluid entering the second storage tank within the ideal temperature range, which specifically includes the following steps: S10, obtaining a current temperature difference between an output temperature of a target fluid and an ideal temperature based on a debugged water outlet temperature sensor; S20, determining whether the current temperature difference is within a preset temperature difference range; S31, if the current temperature difference is within the preset temperature difference range, the exhaust port pressure of the second compressor is obtained based on the debugging pressure sensor 1 as the ideal condensing pressure; S32: If the current temperature difference is not within the preset temperature difference range, the high temperature medium saturation pressure P cse and the minimum condensation pressure of high temperature medium P cmin Determining an ideal condensing pressure until the current temperature difference is within a preset temperature difference range, wherein the high-temperature medium saturation pressure is the saturation pressure of the high-temperature working medium, and the high-temperature working medium is the fluid medium flowing through the second compressor; S40, performing PI control on the condensing pressure based on the ideal condensing pressure and the current temperature difference to determine a target condensing pressure until the current temperature difference is within the ideal temperature difference range; S50, based on the debugging pressure sensor 4, the air inlet pressure of the first compressor is obtained as the low-temperature medium evaporation pressure P of the low-temperature working medium. e ; S60, obtaining the intermediate temperature; S70, adjusting an expansion valve of a second compressor in a high-temperature stage heat pump system according to the intermediate temperature.

10. The Carnot battery control method based on cross-season energy storage technology according to claim 9 is characterized in that: Using the formula: T m ={[T c T e (η L -1)+ΔT m ] / (η H -1)} 0.5 +ΔT m / 2 calculates the intermediate temperature, where η H =T c C Pw m w (T wos -T wis ) / (T c W H -T e W H ), η L =T c1 [C Pw m w (T wos -T wis )-W H ] / (T c1 W L -T e W L ), Among them, T m is the middle temperature, T c is the high temperature medium condensation temperature of the high temperature working medium, T e is the low-temperature evaporation temperature of the low-temperature working medium, η L is the thermodynamic perfection of the low-temperature heat pump, η H is the thermodynamic perfection of the high-temperature heat pump, ΔT m is the heat transfer temperature difference, C Pw is the constant pressure specific heat capacity of the fluid medium, m w is the flow rate of the target fluid, T wos is the ideal temperature of the target fluid, T wi is the inlet temperature of the target fluid, W H is the compression power consumption of the high temperature heat pump, W L is the compression power consumption of the low-temperature heat pump, where the high-temperature medium condensation temperature T c Corresponding to the target condensing pressure, the low temperature medium evaporation temperature T e The low temperature medium evaporation pressure P e Corresponding; wherein the low-temperature working medium is the fluid medium flowing through the first compressor.

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