Deep and shallow dual-mode circulating heat storage tank system based on heat pump and operation regulation and control method thereof

Abstract

The invention discloses a deep and shallow dual-mode circulating heat storage tank system based on a heat pump and an operation regulation and control method of the deep and shallow dual-mode circulating heat storage tank system. The operation regulation and control method comprises the steps that a heat storage water tank, a pressurizing water pump set, a heat pump set, multiple sets of pipeline valves, a first-level network water supply pipeline and a first-level network water return pipeline communicate with one another; a heat storage water supply pipeline, a heat storage pressurization water return pipeline, a conventional shallow heat release pressurization water supply pipeline, a conventional shallow heat release water return pipeline, a deep circulation heat release water supply pipeline and a deep circulation heat release water return pipeline are formed; the scheduling control unit performs comprehensive analysis on a heat supply and demand relationship according to heat supplied by a source side thermal power plant and heat required by a heat supply network and combined with heat storage capacity of a heat storage water tank, and then performs scheduling control according to working conditions on each formed pipeline; and generating a deep and shallow dual-mode scheduling control strategy under a conventional shallow heat storage and release operation condition and a deep circulation heat storage and release operation condition.

Description

Technical Field

[0001] The present invention belongs to the technical field of urban heating systems, and in particular relates to a deep-shallow dual-mode circulation heat storage tank system based on a heat pump and an operation control method thereof. Background Art

[0002] Cities in northern my country generally adopt cogeneration centralized heating systems. With the construction of my country's new energy system, a high proportion of renewable energy is connected to the power system, which makes the heat energy produced by cogeneration units more volatile. The heat storage and heat release capacity of the heat storage tank of the heating system can realize the transfer of heat energy in time, so that the heating system can more flexibly respond to fluctuations in the heat energy production end, and accurately match the demand load through the adjustment of the heat storage tank. During the period of low heat load, the excess heat of the system can be stored in the heat storage tank; and during the peak period of heat load, the heat storage tank can release heat to meet the heat demand of users. This adjustment method not only improves the flexibility of the heating system, but also helps to stabilize the heating temperature and ensure the quality of heating.

[0003] The classic method is to use a direct-connected hot water storage tank configured in the primary network to store high-temperature water from the primary network of the central heating system. After releasing heat, it stores the return water from the primary network. The heat stored in this structure of the heat storage tank depends on the temperature difference between the supply and return water of the primary network. By connecting the heat pump to the heat storage tank, the temperature of the heat storage can be increased, or when releasing heat, the low-temperature water in the heat storage tank can be made lower than the return water temperature of the primary network. The cost is that the operation of the heat pump requires the consumption of high-grade energy such as electricity or gas.

[0004] The function of the heat storage tank needs to be analyzed in the overall operation and scheduling strategy of the heating system. Under some working conditions, the heat energy transfer of the shallow heat storage and release cycle of the heat storage tank can meet the supply and demand balance of the system, and its operating cost is lower. Under other working conditions, the heat storage tank needs to provide a larger amount of heat energy transfer through a deep heat storage and release cycle, which requires a smart operation and scheduling strategy based on the overall supply and demand balance analysis of the heating system.

[0005] However, in actual applications, when a sudden situation occurs that causes insufficient heating capacity and requires the heat storage system to respond, the heat storage system's heat release capacity is often insufficient to maintain the normal operation of the heating system. In order to deal with this problem, it is usually necessary to expand the capacity of the heat storage system. However, the cost of expanding the capacity of the heat storage system is very high, and after the expansion, there is a tendency for low economic benefits and poor flexibility.

[0006] Based on the above technical problems, it is necessary to design a new deep and shallow dual-mode circulation heat storage tank system based on a heat pump and its operation and control method. Summary of the invention

[0007] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a deep and shallow dual-mode circulation heat storage tank system based on a heat pump and an operation and control method thereof. By comprehensively analyzing the heat supply and demand relationship and performing dispatching control according to working conditions, a heat storage tank can be used to achieve supply and demand balance. Moreover, through the combination of a heat pump and a heat storage tank, deep circulation heat release of the heat storage tank is achieved, which significantly improves the heat release capacity of the heat storage tank and improves the stability, economy and flexibility of the heating system.

[0008] In order to solve the above technical problems, the technical solution of the present invention is:

[0009] The present invention provides a deep and shallow dual-mode circulation heat storage tank system based on a heat pump, comprising: a hot water storage tank, a pressurized water pump unit, a heat pump unit, multiple groups of pipeline valves and a dispatching control unit;

[0010] The hot water storage tank is connected to the primary network water supply pipeline through the first valve combination in the multiple groups of pipeline valves, and the high-temperature water in the primary network water supply pipeline is transported to the top of the hot water storage tank after pressure reduction, so as to form a heat storage water supply pipeline;

[0011] The hot water storage tank is connected to the primary network return water pipeline through the second valve combination in the multiple groups of pipeline valves and the pressurized water pump group, and the pressurized water pump group is started to pressurize the water at the bottom of the hot water storage tank and then transport it to the primary network return water pipeline to form a heat storage pressurized return water pipeline;

[0012] The hot water storage tank is connected to the primary network water supply pipeline through the third valve combination in the multiple groups of pipeline valves and the pressurized water pump group. The pressurized water pump group is started to pressurize the high-temperature water at the top of the hot water storage tank and then transport it to the primary network water supply pipeline to form a conventional shallow heat release pressurized water supply pipeline;

[0013] The hot water storage tank is connected to the primary network return water pipeline through the fourth valve combination in the multiple groups of pipeline valves, and the primary network return water pipeline is used to transport and fill the low-temperature water in the primary network return water to the bottom of the hot water storage tank to form a conventional shallow heat release return water pipeline;

[0014] The hot water storage tank is connected to the primary network water supply pipeline through the fifth valve combination, the heat pump unit, and the pressure water pump unit in the multiple groups of pipeline valves. The pressure water pump unit and the heat pump unit are started to transport the low-temperature water in the tank to the condenser side of the heat pump unit for heat absorption and temperature increase, and then transported to the primary network water supply pipeline to form a deep circulation heat release water supply pipeline;

[0015] The hot water storage tank is connected to the primary network return water pipeline through the sixth valve combination in the multiple groups of pipeline valves and the heat pump unit, and the heat pump unit is started to transport a part of the low-temperature water in the primary network return water to the evaporator side of the heat pump unit for cooling into lower temperature water and transporting it to fill the bottom of the hot water storage tank, thereby forming a deep circulation heat release return water pipeline;

[0016] The dispatch control unit is used to perform a comprehensive analysis of the heat supply and demand relationship based on the heat supplied by the source-side thermal power plant and the heat required by the heat network, combined with the heat storage capacity of the hot water storage tank, and then perform dispatch control of the heat storage water supply pipeline, the heat storage pressurized return water pipeline, the conventional shallow heat release pressurized water supply pipeline, the conventional shallow heat release return water pipeline, the deep circulation heat release water supply pipeline and the deep circulation heat release return water pipeline according to different working conditions, so as to generate a deep-shallow dual-mode dispatch control strategy under the conventional shallow heat storage and release operating conditions and the deep circulation heat storage and release operating conditions.

[0017] Furthermore, the first valve combination on the heat storage water supply pipeline includes: opening the thirteenth electric valve (22), the second electric valve (9), the first stop valve (6), and the upper water distribution port (4); the second valve combination on the heat storage pressurized water return pipeline includes: opening the lower water distribution port (5), the second stop valve (7), the third electric valve (10), the sixth electric valve (14), and the tenth electric valve (19).

[0018] Furthermore, the third valve combination on the conventional shallow heat release pressurized water supply pipeline includes: opening the upper water distribution port (4), the first stop valve (6), the first electric valve (8), the sixth electric valve (14), and the eleventh electric valve (20); the fourth valve combination on the conventional shallow heat release return water pipeline includes: opening the twelfth electric valve (21), the fourteenth electric valve (23), the fourth electric valve (12), the second stop valve (7), and the lower water distribution port (5).

[0019] Furthermore, the fifth valve combination on the deep circulation heat release water supply pipeline includes: opening the upper water distribution port (4), the first stop valve (6), the first electric valve (8), the sixth electric valve (14), the eighth electric valve (17), and the seventh electric valve (16); the sixth valve combination on the deep circulation heat release water return pipeline includes: opening the twelfth electric valve (21), the ninth electric valve (18), the fifth electric valve (13), the fourth electric valve (12), the second stop valve (7), and the lower water distribution port (5).

[0020] Furthermore, after the heat storage water supply pipeline and the heat storage pressurized return water pipeline are started and operated, the heat storage process begins. The top of the hot water storage tank is filled with high-temperature water, and the bottom is filled with low-temperature water. A temperature oblique layer is gradually formed in the middle, and the position of the temperature oblique layer gradually moves downward as the heat storage process proceeds until the heat storage is stopped or the heat storage process is completed. After the heat storage process is completed, the hot water storage tank is filled with high-temperature water.

[0021] After the conventional shallow heat release pressurized water supply pipeline and the conventional shallow heat release return water pipeline are started and run, they enter the shallow cycle heat release process. The top of the hot water storage tank is stored high-temperature water, and the bottom is flowing low-temperature water. A temperature gradient layer is gradually formed in the middle, and the position of the temperature gradient layer gradually moves upward as the heat release process proceeds until the heat release stops or the heat release process is completed. After the shallow cycle heat release process is completed, the hot water storage tank is filled with low-temperature water;

[0022] After the shallow cycle heat release process is completed and the deep cycle heat release water supply pipeline and the deep cycle heat release return pipeline are started and operated, the deep cycle heat release process is entered. At the beginning of the deep cycle heat release process, the hot water storage tank is low-temperature water, and the return water from the first-level network enters the evaporator of the heat pump unit for cooling to generate lower temperature water and is sent to the bottom of the tank. At the same time, the low-temperature water left at the top of the tank after the shallow cycle heat release is completed is sent to the condenser of the heat pump unit for heating to generate high-temperature water and is sent to the first-level network for water supply. That is, the heat pump unit absorbs the waste heat of part of the return water from the first-level heating network to heat the low-temperature water supplied from the tank, and the heated high-temperature water is sent to the first-level heating network for water supply for continuous deep cycle heat release of the hot water storage tank.

[0023] Furthermore, after a comprehensive analysis of the heat supply and demand relationship based on the heat supplied by the source-side thermal power plant and the heat demanded by the heat network, combined with the heat storage capacity of the hot water storage tank, the heat storage water supply pipeline, the heat storage pressurized return water pipeline, the conventional shallow heat release pressurized water supply pipeline, the conventional shallow heat release return water pipeline, the deep circulation heat release water supply pipeline and the deep circulation heat release return water pipeline are dispatched and controlled according to different working conditions, and a deep-shallow dual-mode dispatching control strategy under conventional shallow heat storage and release operating conditions and deep circulation heat storage and release operating conditions is generated, which specifically includes:

[0024] Based on the unit operation data of the source-side thermal power plant and the operation data of the heat network, combined with external environmental data, date characteristics and user behavior characteristics, the unit heat supply plan of the source-side thermal power plant and the heat demand value of the heat network are obtained;

[0025] Analyze the heat supply and demand relationship between the heat supply plan of the source-side thermal power plant and the heat demand forecast value of the heat network, and make preliminary time-segment settings for the heat storage and release mode of the hot water storage tank based on the heat supply and demand relationship;

[0026] Based on the initially set heat storage and release mode of the hot water storage tank, the heat storage water supply pipeline and the heat storage pressurized return water pipeline are first started to store heat in the hot water storage tank; when the output of the thermal power plant is insufficient and the hot water storage tank needs to release heat to supplement the heat of the heating network, the conventional shallow heat storage and release operation condition is first entered, and the conventional shallow heat release pressurized water supply pipeline and the conventional shallow heat release return water pipeline are started, and the scheduling control strategy of the hot water storage tank, the pressurized water pump group and multiple groups of pipeline valves is generated; when the unit heat supply value of the thermal power plant does not meet the heat demand value of the heating network and the heat storage amount of the hot water storage tank in the conventional shallow heat release mode is insufficient, then after the conventional shallow heat storage and release operation condition is completed, the deep circulation heat storage and release operation condition is entered, and the deep circulation heat release water supply pipeline and the deep circulation heat release return water pipeline are started, and the scheduling control strategy of the hot water storage tank, the pressurized water pump group, the heat pump unit and multiple groups of pipeline valves is generated.

[0027] Furthermore, under the conventional shallow heat storage and release operating conditions, with the scheduling control cost, operating energy consumption and supply and demand balance as the optimal goal, a conventional shallow heat storage and release optimization scheduling model is established to decide and output the heat storage and release mode and heat storage and release operating power of the hot water storage tank in different time periods, the operating parameters of the booster water pump group, and the start and stop status and valve opening of multiple groups of pipeline valves;

[0028] Under the deep cycle heat storage and release operating conditions, a deep cycle heat storage and release optimization scheduling model is established with the optimization of scheduling control cost, operating energy consumption, heat pump unit efficiency and supply and demand balance as the goals, and the decision output is the heat storage and release mode and heat storage and release operating power of the hot water storage tank in different time periods, the operating parameters of the booster water pump group, the operating parameters of the heat pump unit, the start and stop status of multiple groups of pipeline valves and the valve opening.

[0029] The present invention also provides an operation control method of a deep-shallow dual-mode circulation heat storage tank system based on a heat pump. The operation control method is based on the above-mentioned deep-shallow dual-mode circulation heat storage tank system based on a heat pump, and the operation control method includes:

[0030] S1. Under conventional shallow heat storage and release operating conditions:

[0031] The hot water storage tank is connected to the primary network water supply pipeline through the first valve combination in the multiple groups of pipeline valves, and the high-temperature water in the primary network water supply pipeline is transported to the top of the hot water storage tank after the pressure is reduced, so as to form a heat storage water supply pipeline;

[0032] The hot water storage tank is connected to the primary network return water pipeline through the second valve combination in the multiple groups of pipeline valves and the pressurized water pump group, and the pressurized water pump group is started to pressurize the water at the bottom of the hot water storage tank and then transport it to the primary network return water pipeline to form a heat storage pressurized return water pipeline;

[0033] The hot water storage tank is connected to the primary network water supply pipeline through the third valve combination in the multiple groups of pipeline valves and the pressure water pump group, and the pressure water pump group is started to pressurize the high-temperature water on the top of the hot water storage tank and then transport it to the primary network water supply pipeline to form a conventional shallow heat release pressure water supply pipeline;

[0034] The hot water storage tank is connected to the primary network return water pipeline through the fourth valve combination in the multiple groups of pipeline valves, and the low-temperature water in the heat network return water is transported and filled to the bottom of the hot water storage tank by the primary network return water pipeline to form a conventional shallow heat release return water pipeline;

[0035] S2. Under deep cycle heat storage and release operation conditions:

[0036] After the conventional shallow heat storage and release process is completed, the hot water storage tank is connected to the primary network water supply pipeline through the fifth valve combination, the heat pump unit, and the pressure water pump unit in the multiple groups of pipeline valves, and the pressure water pump unit and the heat pump unit are started to transport the low-temperature water in the tank to the condenser side of the heat pump unit for heat absorption and temperature increase, and then transported to the primary network water supply pipeline for heating, forming a deep circulation heat release water supply pipeline;

[0037] The hot water storage tank is connected to the primary network return water pipeline through the sixth valve combination in the multiple groups of pipeline valves, the heat pump unit, and the heat pump unit is started to transport a part of the low-temperature water in the primary network return water to the evaporator side of the heat pump unit to cool it into lower temperature water and transport it to fill the bottom of the hot water storage tank, thereby forming a deep circulation heat release return water pipeline;

[0038] S3. Set the operation control strategy:

[0039] Based on the unit operation data of the source-side thermal power plant and the operation data of the heat network, combined with external environmental data, date characteristics and user behavior characteristics, the unit heat supply plan of the source-side thermal power plant and the heat demand value of the heat network are obtained;

[0040] Analyze the heat supply and demand relationship between the heat supply plan of the source-side thermal power plant and the heat demand forecast value of the heat network, and set the deep and shallow double-cycle heat storage and release mode of the hot water storage tank according to the heat supply and demand relationship;

[0041] Based on the initially set heat storage and release mode of the hot water storage tank, the heat storage water supply pipeline and the heat storage pressurized return water pipeline are first started to store heat in the hot water storage tank; when the output of the thermal power plant is insufficient and the hot water storage tank needs to release heat to supplement the heat of the heating network, the conventional shallow heat storage and release operation condition is first entered, and the conventional shallow heat release pressurized water supply pipeline and the conventional shallow heat release return water pipeline are started, and the scheduling control strategy of the hot water storage tank, the pressurized water pump group and multiple groups of pipeline valves is generated; when the unit heat supply value of the thermal power plant does not meet the heat demand value of the heating network and the heat storage amount of the hot water storage tank in the conventional shallow heat release mode is insufficient, then after the conventional shallow heat storage and release operation condition is completed, the deep circulation heat storage and release operation condition is entered, and the deep circulation heat release water supply pipeline and the deep circulation heat release return water pipeline are started, and the scheduling control strategy of the hot water storage tank, the pressurized water pump group, the heat pump unit and multiple groups of pipeline valves is generated.

[0042] The beneficial effects of the present invention are:

[0043] The present invention connects the heat storage tank, the pressurized water pump group, the heat pump unit, and multiple groups of pipeline valves, so that the heating system establishes a heat storage water supply pipeline, a heat storage pressurized return water pipeline, a conventional shallow heat release pressurized water supply pipeline, a conventional shallow heat release return water pipeline, a deep circulation heat release water supply pipeline, and a deep circulation heat release return water pipeline. The scheduling control unit then analyzes and decides to generate a deep and shallow double circulation scheduling control strategy under conventional shallow heat storage and release operating conditions and deep circulation heat storage and release operating conditions. By comprehensively analyzing the heat supply and demand relationship and performing scheduling control according to different operating conditions, the heat storage tank can be used to achieve supply and demand. Balance, and through the combination of the heat pump unit and the hot water storage tank, the deep circulation heat release of the hot water storage tank is realized, which significantly improves the heat release capacity of the hot water storage tank and improves the stability, economy and flexibility of the heating system; in addition, the scheduling control strategies under different working conditions can cope with different load conditions and external environmental changes, and enhance the flexibility and responsiveness of the system; and, through the natural stratification and inclined temperature layer management of the hot water storage tank, a more stable water supply temperature can be provided, which improves the user's comfort, and when the heat supply is insufficient or in emergency conditions, it can make up for the missing heat and ensure the continuous operation of the system.

[0044] Other features and advantages will be described in the following description, and partly become apparent from the description, or understood by practicing the invention. The purpose and other advantages of the invention are realized and obtained by the structures particularly pointed out in the description and the drawings.

[0045] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0047] Figure 1 It is a schematic diagram of the overall structure of a deep and shallow dual-mode circulation heat storage tank system based on a heat pump of the present invention;

[0048] Figure 2 It is a schematic diagram of the structure of the hot water storage tank of the present invention when storing heat;

[0049] Figure 3 This is a schematic diagram of the shallow cycle heat release structure of the present invention;

[0050] Figure 4 This is a schematic diagram of the deep cycle heat release structure of the present invention;

[0051] Figure 5 This is an example diagram of the working conditions of the deep and shallow dual-mode circulation heat storage tank system based on the heat pump of the present invention.

[0052] Description of reference numerals:

[0053] 1. Hot water storage tank; 2. Condenser; 3. Evaporator; 4. Upper water distribution port; 5. Lower water distribution port; 6. First stop valve; 7. Second stop valve; 8. First electric valve; 9. Second electric valve; 10. Third electric valve; 11. Pressurized water pump unit; 12. Fourth electric valve; 13. Fifth electric valve; 14. Sixth electric valve; 15. Heat pump unit; 16. Seventh electric valve; 17. Eighth electric valve; 18. Ninth electric valve; 19. Tenth electric valve; 20. Eleventh electric valve; 21. Twelfth electric valve; 22. Thirteenth electric valve; 23. Fourteenth electric valve; 24. Water replenishment device. DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are 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.

[0055] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "interconnected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0056] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0057] Example 1

[0058] like Figures 1 to 4 As shown, this embodiment 1 provides a deep-shallow dual-mode circulation heat storage tank system based on a heat pump, comprising: a hot water storage tank (1), a pressurized water pump group (11), a heat pump unit (15), a plurality of pipeline valves and a scheduling control unit;

[0059] The hot water storage tank (1) is connected to the primary network water supply pipeline through the first valve combination in the plurality of pipeline valve groups, and the high-temperature water in the primary network water supply pipeline is transported to the top of the hot water storage tank (1) after the pressure is reduced, so as to form a heat storage water supply pipeline;

[0060] The hot water storage tank (1) is connected to the primary network return water pipeline through the second valve combination in the plurality of pipeline valve groups and the pressurized water pump group (11), and the pressurized water pump group (11) is started to pressurize the water at the bottom of the hot water storage tank (1) and then transport it to the primary network return water pipeline, thereby forming a heat storage pressurized return water pipeline;

[0061] The hot water storage tank (1) is connected to the primary network water supply pipeline through the third valve combination in the plurality of pipeline valve groups and the pressurized water pump group (11), and the pressurized water pump group (11) is started to pressurize the high-temperature water at the top of the hot water storage tank (1) and then transport it to the primary network water supply pipeline, thereby forming a conventional shallow heat release pressurized water supply pipeline;

[0062] The hot water storage tank (1) is connected to the primary network return water pipeline via the fourth valve combination in the plurality of pipeline valve groups, and the primary network return water pipeline is used to transport low-temperature water in the primary network return water to fill the bottom of the hot water storage tank (1), thereby forming a conventional shallow heat release return water pipeline;

[0063] The hot water storage tank (1) is connected to the primary network water supply pipeline through the fifth valve combination in the plurality of pipeline valve groups, the heat pump unit (15), and the pressure water pump unit (11). The pressure water pump unit (11) and the heat pump unit (15) are started to transport the low-temperature water in the tank to the condenser (2) side of the heat pump unit (15) for heat absorption and temperature increase, and then transported to the primary network water supply pipeline to form a deep circulation heat release water supply pipeline;

[0064] The hot water storage tank (1) is connected to the primary network return water pipeline through the sixth valve combination in the plurality of pipeline valve groups and the heat pump unit (15), and the heat pump unit (15) is started to transport a portion of low-temperature water in the primary network return water to the evaporator (3) side of the heat pump unit (15), where it is cooled into even lower-temperature water and transported to fill the bottom of the hot water storage tank, thereby forming a deep circulation heat release return water pipeline;

[0065] The dispatch control unit is used to perform a comprehensive analysis of the heat supply and demand relationship based on the heat supplied by the source-side thermal power plant and the heat required by the heat network, combined with the heat storage capacity of the hot water storage tank (1), and then perform dispatch control of the heat storage water supply pipeline, the heat storage pressurized water return pipeline, the conventional shallow heat release pressurized water supply pipeline, the conventional shallow heat release return pipeline, the deep circulation heat release water supply pipeline and the deep circulation heat release return pipeline according to different working conditions, so as to generate a deep-shallow dual-mode dispatch control strategy under the conventional shallow heat storage and release operating conditions and the deep circulation heat storage and release operating conditions.

[0066] In actual applications, the deep and shallow dual-mode circulation heat storage tank system based on the heat pump has different operating conditions at different stages of the heating season. There are three operating modes, including: heat storage condition, see Figure 2 ; Shallow heat release condition, see Figure 3 ; Deep heat release condition, see Figure 4 .

[0067] When the power plant's heating output is sufficient, the heat storage state is entered. During the heat storage stage in the heating season, the hot water storage tank (1) is connected to the primary network water supply pipeline, and the primary network warm water with a temperature of T1 is sent to the hot water storage tank (1). The cold water in the lower part of the tank is boosted by the pressure water pump group (11) and then sent back to the primary network. After the heat storage process is completed, the water temperature in the tank is T1.

[0068] When the heating output of the thermal power plant is weak and the hot water storage tank (1) is needed to supplement the heat to the heating network, the conventional shallow heat release condition is entered, and the hot water storage tank (1) is used to supply heat to the outside. The high-temperature water with a temperature of T1 in the hot water storage tank (1) is pressurized by the pressure water pump group (11) and then sent to the primary network for water supply and heat supplement. A portion of the low-temperature water with a temperature of T2 in the return water of the heating network is filled to the bottom of the hot water storage tank (1); if the conventional shallow heat release condition continues to release heat until the high-temperature water with a temperature of T1 in the hot water storage tank (1) is completely consumed, and the heating network still needs the hot water storage tank (1) to supplement the heat, then the hot water storage tank (1) is deep-circulated to release heat, and the conventional shallow heat release condition is used. After the thermal process is completed, the heat pump unit (15) in the system is started, and the return water with a temperature of T2 in the primary heating network is sent to the evaporator (3) of the heat pump unit (15) to cool down and generate lower temperature water with a temperature of T3, which is sent to the bottom of the tank. At the same time, the low temperature water with a temperature of T2 left after the shallow heat release in the top of the tank is sent to the condenser (2) of the heat pump unit (15) to heat up and generate heated water with a temperature of T4, which is sent to the heating network. That is, the heat pump unit (15) absorbs the waste heat of part of the return water of the primary heating network to heat the low temperature water supplied from the tank, and the heated high temperature water is sent to the primary heating network to supply water for continuous deep circulation heat release in the hot water storage tank (1).

[0069] See the application example of the deep and shallow dual-mode circulation heat storage tank system based on the heat pump for Figure 5 In the figure, the solid line represents the output of the heat source, the dotted line represents the demand of the heat network, the area of ​​the left oblique line represents the heat storage process and its load, the area of ​​the horizontal line represents the shallow heat release process and its load, and the area of ​​the vertical line represents the deep heat release process and its load. In the figure, areas ①, ②, ③, and ④ represent the heat storage process of the heat source to the hot water storage tank system when the output of the thermal power plant is abundant. Areas ⑤, ⑥, ⑦, ⑧, and ⑨ in the figure represent the process of the heat storage tank system supplementing heat to the heat network when the output of the thermal power plant is insufficient. Among them, areas ⑤, ⑥, and ⑧ represent the shallow heat release working process of the hot water storage tank, and areas ⑦ and ⑨ represent the deep heat release working process entering the hot water storage tank. It can be seen from the figure that the above three working conditions can achieve peak shaving and valley filling when the heating output of the thermal power plant fluctuates. In particular, the deep circulation heat release system further enhances the peak-shaving capacity and peak-shaving flexibility, which plays an important role in the stability of the heat network.

[0070] It should be noted that the heat pump unit uses a supercritical cycle heat pump unit, which is a highly efficient heat energy conversion device that uses the special properties of the working medium in a supercritical state to achieve efficient heat energy transfer. Compared with the traditional subcritical cycle, the supercritical cycle can operate at higher temperatures and pressures, thereby improving the efficiency and applicability of the system. The following is the technical principle of the supercritical cycle heat pump:

[0071] 1. Working medium

[0072] Supercritical fluid: Carbon dioxide (CO2) is usually used as the working medium because it has a low critical point (31.1°C, 7.38MPa) and good environmental properties;

[0073] Other media: Other suitable fluids can be used, such as certain Freon substitutes or ammonia, but carbon dioxide is the most common choice;

[0074] 2. Supercritical state

[0075] Critical point: When the pressure and temperature of a fluid exceed its critical point, the fluid enters a supercritical state. In this state, the fluid is neither a typical gas nor a liquid, but has some unique physical properties;

[0076] Density variation: The density of a supercritical fluid can be significantly adjusted by varying the pressure and temperature, which makes it very efficient in heat transfer processes;

[0077] 3. Cyclic process

[0078] The basic cycle of a supercritical cycle heat pump includes the following steps:

[0079] Compression: Use a compressor to compress a low-pressure and low-temperature working medium (usually a gas) to a high-pressure and high-temperature state. In this process, the energy of the working medium increases and the temperature rises;

[0080] Condensation / Exothermicity: The high-pressure and high-temperature working medium releases heat to the external system (such as the heating system) through the condenser. Due to the supercritical state, no phase change occurs, but by reducing the temperature, the working medium can still effectively release a large amount of heat.

[0081] Throttling / Expansion: The high-pressure working medium passes through the expansion valve to reduce the pressure and the temperature drops accordingly. This process is similar to the throttling process in a traditional heat pump, but in a supercritical cycle, the working medium does not undergo a phase change;

[0082] Evaporation / absorption of heat: The low-pressure and low-temperature working medium absorbs heat from an external source (such as air, groundwater or geothermal heat) through the evaporator. Since the working medium is still in a supercritical state, it can efficiently absorb heat and increase its own temperature and pressure.

[0083] It should be noted that the necessity of adding a booster pump group is as follows:

[0084] 1. Maintain system pressure

[0085] Maintain circulation pressure: The return water pipeline of the heating network usually needs to maintain a certain pressure to ensure the normal operation of the entire heating system. If low-temperature water is directly extracted from the hot water storage tank without pressurization, the return water pipeline may be under-pressured, affecting the stability and efficiency of the system;

[0086] Overcoming resistance: Hot water will encounter various resistances during its flow, such as pipe friction, elbows, valves, etc. A pressurized water pump can provide sufficient power to overcome these resistances and ensure smooth water flow;

[0087] 2. Promote natural stratification

[0088] Maintain temperature stratification: The water in the hot water storage tank is naturally stratified due to density differences, with high-temperature water at the top and low-temperature water at the bottom. By pumping low-temperature water from the bottom with a pressurized water pump, mixing of hot and cold water can be avoided, maintaining the temperature gradient inside the hot water storage tank and improving heat storage efficiency;

[0089] 3. Improve energy efficiency

[0090] Energy-saving operation: The booster pump can adjust the output power according to actual needs, making the pumping process more efficient. The application of modern frequency conversion technology can enable the booster pump to automatically adjust the speed according to system needs, further saving energy;

[0091] Optimize flow control: Through the booster pump, the flow entering the return pipe of the heating network can be more accurately controlled to ensure that the system operates on demand and avoid unnecessary energy waste;

[0092] 4. System balance

[0093] Maintain system balance: The booster pump ensures that the amount of water flowing out of the hot water storage tank matches the amount of water entering the hot water storage tank, thereby maintaining the hydraulic balance of the entire system;

[0094] Prevent cavitation: Appropriate pressurization can prevent cavitation caused by low inlet pressure in the water pump, thus protecting the water pump and other equipment from damage;

[0095] 5. Operational flexibility

[0096] Flexible adjustment: Through the booster pump, the water supply pressure and flow rate can be flexibly adjusted according to different working conditions and needs, so that the system can better adapt to changing load conditions;

[0097] Simplified design: Using a pressurized water pump can simplify the system design, reduce the need for complex pressure regulating devices, and reduce system complexity and maintenance costs;

[0098] 6. Security

[0099] Prevent backflow: The pressure water pump can prevent the water in the return pipe of the heating network from flowing back into the hot water storage tank, ensuring the safe operation of the system;

[0100] Emergency handling: In an emergency, the water supply to the heat network return pipe can be quickly cut off or reduced by controlling the booster pump to ensure the safety of the system;

[0101] The purpose of using a pressure pump to pressurize the water at the bottom of the hot water storage tank and then transport it to the return water pipeline of the heating network is to maintain the system pressure, promote natural stratification, improve energy efficiency, maintain system balance, increase operational flexibility and ensure safety. This design helps to achieve efficient thermal energy storage and release while ensuring the stable operation of the entire heating system. Through reasonable pressurization and flow control, the heat in the hot water storage tank can be maximized to improve the performance and reliability of the overall system.

[0102] In this embodiment, the first valve combination on the heat storage water supply pipeline includes: opening the thirteenth electric valve (22), the second electric valve (9), the first stop valve (6), and the upper water distribution port (4); the second valve combination on the heat storage pressurized water return pipeline includes: opening the lower water distribution port (5), the second stop valve (7), the third electric valve (10), the sixth electric valve (14), and the tenth electric valve (19).

[0103] In actual application, the start and stop states of the equipment components in the heat storage process include: the first stop valve (6) and the second stop valve (7) are in an open state; the upper water distribution port (4) and the lower water distribution port (5) are in an open state; the second electric valve (9), the third electric valve (10), the sixth electric valve (14), the tenth electric valve (19), and the thirteenth electric valve (22) are in an open state; the first electric valve (8), the fourth electric valve (12), the fifth electric valve (13), the seventh electric valve (16), the eighth electric valve (17), the ninth electric valve (18), the eleventh electric valve (20), the twelfth electric valve (21), and the fourteenth electric valve (23) are in a closed state.

[0104] In this embodiment, the third valve combination on the conventional shallow heat release pressurized water supply pipeline includes: opening the upper water distribution port (4), the first stop valve (6), the first electric valve (8), the sixth electric valve (14), and the eleventh electric valve (20); the fourth valve combination on the conventional shallow heat release return water pipeline includes: opening the twelfth electric valve (21), the fourteenth electric valve (23), the fourth electric valve (12), the second stop valve (7), and the lower water distribution port (5).

[0105] In actual application, the start and stop states of the equipment components in the conventional shallow heat release process include: the first stop valve (6) and the second stop valve (7) are in the open state; the upper water distribution port (4) and the lower water distribution port (5) are in the open state; the first electric valve (8), the fourth electric valve (12), the sixth electric valve (14), the eleventh electric valve (20), the twelfth electric valve (21), and the fourteenth electric valve (23) are in the open state; the second electric valve (9), the third electric valve (10), the fifth electric valve (13), the seventh electric valve (16), the eighth electric valve (17), the ninth electric valve (18), the tenth electric valve (19), and the thirteenth electric valve (22) are in the closed state.

[0106] In this embodiment, the fifth valve combination on the deep circulation heat release water supply pipeline includes: opening the upper water distribution port (4), the first stop valve (6), the first electric valve (8), the sixth electric valve (14), the eighth electric valve (17), and the seventh electric valve (16); the sixth valve combination on the deep circulation heat release water return pipeline includes: opening the twelfth electric valve (21), the ninth electric valve (18), the fifth electric valve (13), the fourth electric valve (12), the second stop valve (7), and the lower water distribution port (5).

[0107] In actual application, the start and stop states of the equipment components in the deep cycle heat release process include: the first stop valve (6) and the second stop valve (7) are in the open state; the upper water distribution port (4) and the lower water distribution port (5) are in the open state; the first electric valve (8), the fourth electric valve (12), the fifth electric valve (13), the sixth electric valve (14), the seventh electric valve (16), the eighth electric valve (17), the ninth electric valve (18), and the twelfth electric valve (21) are in the open state; the second electric valve (9), the third electric valve (10), the tenth electric valve (19), the eleventh electric valve (20), and the thirteenth electric valve (22) are in the closed state. It should be noted that the deep cycle heat release process is realized on the basis of the conventional shallow heat release process.

[0108] In this embodiment, the heat storage water supply pipeline and the heat storage pressurized return water pipeline are started and enter the heat storage process. The top of the hot water storage tank (1) is filled with high-temperature water with a temperature of T1, and the bottom is filled with low-temperature water with a temperature of T2. A temperature oblique layer is gradually formed in the middle, and the position of the temperature oblique layer gradually moves downward as the heat storage process proceeds until the heat storage is stopped or the heat storage process is completed. After the heat storage process is completed, the hot water storage tank (1) is filled with high-temperature water with a temperature of T1.

[0109] After the conventional shallow heat release pressurized water supply pipeline and the conventional shallow heat release return water pipeline are started and operated, they enter a shallow cycle heat release process. The top of the hot water storage tank (1) is stored with high-temperature water at a temperature of T1, and the bottom is flowing with low-temperature water at a temperature of T2. A temperature oblique layer is gradually formed in the middle, and the position of the temperature oblique layer gradually moves upward as the heat release process proceeds until the heat release stops or the heat release process is completed. After the shallow cycle heat release process is completed, the hot water storage tank (1) is filled with low-temperature water at a temperature of T2.

[0110] After the shallow cycle heat release process is completed and the deep cycle heat release water supply pipeline and the deep cycle heat release return pipeline are started and operated, the deep cycle heat release process is entered. At the beginning of the deep cycle heat release process, the hot water storage tank is low-temperature water, and the return water of the primary network enters the evaporator (3) of the heat pump unit (15) to cool down to generate lower temperature water and send it to the bottom of the tank. At the same time, the low-temperature water left at the top of the tank after the shallow cycle heat release is completed is sent to the condenser (2) of the heat pump unit (15) to heat up to generate high-temperature water and send it to the primary network for water supply, that is, the waste heat of part of the return water of the heating primary network is absorbed by the heat pump unit (15) to supply the tank. The supplied low-temperature water is heated, and the heated high-temperature water is sent to the primary heating network for water supply to carry out continuous deep circulation heat release in the hot water storage tank (1); wherein the top of the hot water storage tank (1) is low-temperature water with a temperature of T2 left after the shallow circulation heat release is completed, and the bottom flows in with a portion of the first network return water with a lower temperature of T3 after being cooled by the heat pump unit (15). The other side of the heat pump unit (15) heats the low-temperature water with a temperature of T2 at the top of the hot water storage tank (1) to heated water with a temperature of T4, and uses the heated water to carry out continuous deep circulation heat release in the hot water storage tank (1).

[0111] It should be noted that the basic principle of water tank heat storage is relatively simple. The heat storage tank uses water as the heat storage medium and achieves the purpose of heat storage through the natural stratification of cold and hot water. The overall liquid level of the heat storage tank remains unchanged during the heat storage and release process, and the height of the alternating surface of cold and hot water (i.e., the inclined temperature layer) changes continuously.

[0112] A hot water storage tank is a device used to store hot water. It is usually used in a heating system to adjust the heat load, balance supply and demand, and improve the overall efficiency of the system. Its technical principles mainly involve the following aspects:

[0113] 1. Heat storage medium

[0114] Water: The most common heat storage medium is water because it has a high specific heat capacity and good thermal conductivity;

[0115] Phase change materials (optional): In some advanced designs, phase change materials (such as paraffin, salts, etc.) can be used. These materials can undergo phase changes at specific temperatures, thereby storing or releasing large amounts of latent heat;

[0116] 2. Structure and design

[0117] Tank: Hot water storage tanks are usually made of stainless steel or other corrosion-resistant materials to ensure safety and reliability in long-term use;

[0118] Insulation: To reduce heat loss, the outside of the tank is usually wrapped with highly efficient insulation materials such as polyurethane foam or rock wool;

[0119] Inlet / outlet pipe: The tank body is provided with an inlet pipe and an outlet pipe, which are used to introduce water into the tank and flow water out of the tank respectively;

[0120] Temperature sensors: Temperature sensors installed at different locations inside the tank are used to monitor water temperature for control and management purposes;

[0121] Pressure balancing device: Although it is called a "hot water storage tank", in actual operation, there will be a certain amount of static water pressure in the tank. An expansion pipe or a breathing valve is usually installed on the top of the tank to prevent internal pressure fluctuations caused by temperature changes;

[0122] 3. Working Principle

[0123] Heat storage process:

[0124] When the hot water generated by the heat source in the system (such as boiler, heat pump, etc.) exceeds the current demand, the excess hot water will be sent to the hot water storage tank for storage;

[0125] Hot water enters the tank and naturally stratifies based on density differences, with hotter water at the top and cooler water at the bottom.

[0126] The insulation layer can effectively reduce heat loss and maintain the water temperature in the tank;

[0127] Exothermic process:

[0128] When the heat load in the system increases and more hot water is needed, the hot water in the hot water storage tank will be drawn out and supplied to users or added to the system.

[0129] Due to natural stratification, the hotter water in the upper part is extracted first, thus ensuring the temperature of the supplied hot water is higher;

[0130] If the water temperature in the tank is lower than the set value, the water in the tank can be reheated by a heat source;

[0131] 4. Control system

[0132] Automatic control: Modern hot water storage tanks are usually equipped with automatic control systems, including temperature sensors, controllers and actuators (such as valves and pumps);

[0133] Temperature control: The controller automatically adjusts the output power of the heat source and the opening of the inlet and outlet valves according to the feedback signal of the temperature sensor to maintain the water temperature in the tank within the set range.

[0134] The hot water storage tank does not distinguish whether it is a normal pressure water storage tank or not. In essence, the same purpose can be achieved through the pressure increase and decrease device, so no distinction is made. The hot water storage tank can play a role in regulating the heat load and balancing supply and demand in the heating system by storing and releasing hot water. Its working principle is based on the natural stratification of water and insulation technology, combined with the automatic control system, it can efficiently and stably provide users with the required hot water, which helps to improve the overall performance and economic benefits of the system.

[0135] In the actual application process, the conventional heat storage and release operation mode is adopted under most operating conditions. The heat storage process is realized by using the heat storage water supply pipeline and the heat storage pressurized return water pipeline, and the heat release process is realized by using the conventional shallow heat release pressurized water supply pipeline and the conventional shallow heat release return water pipeline. The heat storage and heat release of the hot water storage tank are within the expected range and can meet the overall heat demand of the heating network. Under individual operating conditions, such as a sudden increase in the demand for heat load in extremely cold weather or an abnormal fault at the end, the heat storage of the hot water storage tank is insufficient to meet the demand. If the output of the heat source unit of the thermal power plant is increased, Due to the thermoelectric coupling characteristics of the thermal power plant units, it will inevitably affect the power supply of the thermal power plant, cause the dispatch plan of the thermal power plant to be disordered, and increase the output cost of the units. In order to reduce operating costs and meet heat needs, the system needs to switch to the deep circulation heat release mode after the shallow heat release mode is completed. The heat pump unit absorbs part of the return water from the primary heating network to heat the low-temperature water supplied from the tank. The heated high-temperature water is sent to the primary heating network for water supply for continuous deep circulation heat release in the hot water storage tank, achieving more continuous heat release, significantly improving energy utilization efficiency and reducing operating costs.

[0136] In this embodiment, after a comprehensive analysis of the heat supply and demand relationship based on the heat supplied by the source-side thermal power plant and the heat required by the heat network, combined with the heat storage capacity of the hot water storage tank, the heat storage water supply pipeline, the heat storage pressurized return water pipeline, the conventional shallow heat release pressurized water supply pipeline, the conventional shallow heat release return water pipeline, the deep circulation heat release water supply pipeline and the deep circulation heat release return water pipeline are dispatched and controlled according to different working conditions, and a deep-shallow dual-mode dispatching control strategy under conventional shallow heat storage and release operating conditions and deep circulation heat storage and release operating conditions is generated, which specifically includes:

[0137] Based on the unit operation data of the source-side thermal power plant and the operation data of the heat network, combined with external environmental data, date characteristics and user behavior characteristics, the unit heat supply plan of the source-side thermal power plant and the heat demand value of the heat network are obtained;

[0138] Analyze the heat supply and demand relationship between the heat supply plan of the source-side thermal power plant and the heat demand forecast value of the heat network, and make preliminary time-segment settings for the heat storage and release mode of the hot water storage tank based on the heat supply and demand relationship;

[0139] Based on the heat storage and release mode of the initially set hot water storage tank (1), the heat storage water supply pipeline and the heat storage pressurized return water pipeline are first started to store heat in the hot water storage tank; when the output of the thermal power plant is insufficient and the hot water storage tank needs to release heat to supplement the heat of the heating network, the conventional shallow heat storage and release operation condition is first entered, the conventional shallow heat release pressurized water supply pipeline and the conventional shallow heat release return water pipeline are started, and the scheduling control strategy of the hot water storage tank (1), the pressurized water pump group (11) and the multiple groups of pipeline valves is generated; when the heat supply value of the unit of the thermal power plant does not meet the heat demand value of the heating network and the heat storage surplus of the hot water storage tank (1) in the conventional shallow heat release mode is insufficient, then after the conventional shallow heat storage and release operation condition is completed, the deep circulation heat storage and release operation condition is entered, the deep circulation heat release water supply pipeline and the deep circulation heat release return water pipeline are started, and the scheduling control strategy of the hot water storage tank (1), the pressurized water pump group (11), the heat pump unit (15) and the multiple groups of pipeline valves is generated.

[0140] In actual applications, the output of the thermal power plant units on the source side has the characteristics of thermoelectric coupling. During the period of low electricity demand, the excess electricity can be used to heat the hot water in the heating network and store it in the hot water storage tank. During the period of low heat load demand, when the heat supply is greater than the demand, the excess heat can be stored in the hot water storage tank, and the heat storage and release of the hot water storage tank can be used to achieve the balance of heat supply and demand. In addition, through the combination of the heat pump unit and the hot water storage tank, the deep circulation heat release of the hot water storage tank is realized, which significantly improves the heat release capacity of the hot water storage tank and improves the stability, economy and flexibility of the heating system.

[0141] In this embodiment, under the conventional shallow heat storage and release operating conditions, with the scheduling control cost, operating energy consumption and supply and demand balance as the optimal goal, a conventional shallow heat storage and release optimization scheduling model is established to decide and output the heat storage and release mode and heat storage and release operating power of the hot water storage tank (1) in different time periods, the operating parameters of the booster water pump group (11), the start and stop status of multiple groups of pipeline valves and the valve opening;

[0142] Under the deep cycle heat storage and release operating condition, a deep cycle heat storage and release optimization scheduling model is established with the scheduling control cost, operating energy consumption, heat pump unit efficiency and supply and demand balance as the optimal goal, and the decision output is the heat storage and release mode and heat storage and release operating power of the hot water storage tank (1), the operating parameters of the booster water pump group (11), the operating parameters of the heat pump unit (15), the start and stop status and valve opening of multiple groups of pipeline valves in different time periods.

[0143] In practical applications, under the conventional shallow heat storage and release operating conditions, the scheduling control cost, operating energy consumption and supply and demand balance are optimized as the goals, which are expressed as:

[0144]

[0145] C1 is the dispatching control cost under the conventional shallow heat storage and release operation condition; Ch,t is the operating cost of the thermal power plant on the source side during period t under conventional shallow heat storage and release operation conditions; C p,t is the operating cost of the booster pump group during period t under conventional shallow heat storage and release operating conditions; C s,t is the heat storage and release operation cost of the hot water storage tank during period t under the conventional shallow heat storage and release operation condition; T is the scheduling period of the conventional shallow heat storage and release operation condition;

[0146]

[0147] E1 is the operating energy consumption under conventional shallow heat storage and release operating conditions; P pump,t is the unit operating energy consumption of the booster pump group in period t under the conventional shallow heat storage and release operating conditions; t pump is the operating time of the booster water pump group under conventional shallow heat storage and release operating conditions;

[0148]

[0149] Q1 is the supply-demand balance deviation under conventional shallow heat storage and release operation conditions; Q h,t is the heat supply value of the thermal power plant on the source side during period t under the conventional shallow heat storage and release operation condition; Q s,t Q is the heat release of the hot water tank during period t under conventional shallow heat storage and release operation conditions; d,t is the heat demand of the heat network in period t under the conventional shallow heat storage and release operation condition;

[0150] The constraints of the conventional shallow heat storage and release optimization scheduling model are set, including at least:

[0151] The capacity limit of the hot water storage tank is expressed as:

[0152] V min ≤V(t)≤V max ;

[0153] V(t) is the amount of water in the hot water tank during period t; V min 、V max are the minimum and maximum volumes of the hot water storage tank, respectively;

[0154] The temperature constraint of the hot water storage tank is expressed as:

[0155] T min ≤T(t)≤T max ;

[0156] T(t) is the average temperature of water in the hot water storage tank during period t; T min , T max are the minimum and maximum permissible temperatures of the hot water storage tank, respectively;

[0157] The position constraint of the thermocline layer is expressed as:

[0158] L thermocline,min ≤L thermocline (t)≤L thermocline,max ;

[0159] L thermocline (t) is the position of the thermocline layer during time period t; L thermocline,min , L thermocline,max are the minimum and maximum permissible positions of the thermocline, respectively;

[0160] The operating limit of the booster pump group is expressed as:

[0161] P pump,min ≤P pump (t)≤P pump,max ;

[0162] P pump (t) is the operating frequency of the booster pump group; P pump,min , P pump,max They are the minimum and maximum operating power of the booster water pump group respectively.

[0163] In practical applications, under the deep cycle heat storage and release operating conditions, the scheduling control cost, operating energy consumption, heat pump unit efficiency and supply and demand balance are optimized as the goals, which are expressed as:

[0164]

[0165] C2 is the dispatching control cost under the deep cycle heat storage and release operation condition; C h ' ,t is the operating cost of the thermal power plant on the source side during period t under the deep cycle heat storage and release operation condition; C p ' ,t is the operating cost of the booster pump group during period t under deep cycle heat storage and release operation conditions; C s ' ,t is the heat storage and release operation cost of the hot water storage tank during period t under the deep cycle heat storage and release operation condition; C h ' p,t is the operating cost of the heat pump unit in period t under the deep cycle heat storage and release operation condition; T′ is the scheduling period of the deep cycle heat storage and release operation condition;

[0166]

[0167] E2 is the operating energy consumption under deep cycle heat storage and release operation conditions; P p ' ump,t is the unit operating energy consumption of the booster water pump group in period t under the deep cycle heat storage and release operation condition; t′ pumpP is the operating time of the booster pump group under deep cycle heat storage and release operating conditions; hp,t is the unit operating energy consumption of the heat pump unit in period t under the deep cycle heat storage and release operation condition; t hp The operation time of the heat pump unit under deep cycle heat storage and release operation conditions;

[0168]

[0169] COP is the operating efficiency of the heat pump unit under deep cycle heat storage and release operation conditions; Q hp,t W is the heat output of the heat pump unit during period t under deep cycle heat storage and release operation conditions; in,t is the amount of electricity input by the heat pump unit during period t under deep cycle heat storage and release operation conditions;

[0170]

[0171] Q2 is the supply-demand balance deviation under deep cycle heat storage and release operation conditions; Q h ' ,t is the heat supply value of the thermal power plant on the source side during period t under the deep cycle heat storage and release operation condition; Q s ' ,t Q is the heat release of the hot water tank during period t under deep cycle heat storage and release operation; d ' ,t is the heat demand of the heating network in period t under the deep cycle heat storage and release operation condition;

[0172] The constraints of the deep cycle heat storage and release optimization scheduling model are set. In addition to the hot water storage tank capacity constraints, hot water storage tank temperature constraints, inclined temperature layer position constraints, and booster pump operation restrictions, the power constraints, temperature constraints, and energy balance constraints of the heat pump unit are also included, which are expressed as:

[0173] P min ≤W in (t)≤P max ;

[0174] W in (t) is the electric energy input by the heat pump unit during period t; P min , P max Minimum and maximum values ​​of electrical energy input to the heat pump unit;

[0175] T cond,min ≤T cond (t)≤T cond,max ;

[0176] T evap,min ≤T evap (t)≤T evap,max ;

[0177] T cond (t) is the condenser temperature during period t; T cond,min , T cond,max are the minimum and maximum values ​​of the condenser respectively; T evap (t) is the evaporator temperature during period t; T evap,min , T evap,max are the minimum and maximum values ​​of the evaporator temperature respectively;

[0178] Q out (t) = f(T cond (t),T evap (t));

[0179] f is a function that describes the relationship between the heat output of the heat pump unit and the temperatures of the condenser and evaporator.

[0180] Example 2

[0181] This embodiment 2 proposes an operation control method for a deep-shallow dual-mode circulation heat storage tank system based on a heat pump. The operation control method is applied to the deep-shallow dual-mode circulation heat storage tank system based on a heat pump. The operation control method includes:

[0182] S1. Under conventional shallow heat storage and release operating conditions:

[0183] The hot water storage tank (1) is connected to the primary network water supply pipeline through the first valve combination in the plurality of pipeline valve groups, and the high-temperature water in the primary network water supply pipeline is transported to the top of the hot water storage tank (1) after the pressure is reduced, so as to form a heat storage water supply pipeline;

[0184] The hot water storage tank (1) is connected to the primary network return water pipeline through the second valve combination in the plurality of pipeline valve groups and the pressurized water pump group (11), and the pressurized water pump group (11) is started to pressurize the water at the bottom of the hot water storage tank (1) and then transport it to the primary network return water pipeline, thereby forming a heat storage pressurized return water pipeline;

[0185] The hot water storage tank (1) is connected to the primary network water supply pipeline through the third valve combination in the plurality of pipeline valve groups and the pressurized water pump group (11), and the pressurized water pump group (11) is started to pressurize the high-temperature water at the top of the hot water storage tank (1) and then transport it to the primary network water supply pipeline, thereby forming a conventional shallow heat release pressurized water supply pipeline;

[0186] The hot water storage tank (1) is connected to the primary network return water pipeline through the fourth valve combination in the plurality of pipeline valve groups, and the primary network return water pipeline is used to transport low-temperature water in the heat network return water to fill the bottom of the hot water storage tank (1), thereby forming a conventional shallow heat release return water pipeline;

[0187] S2. Under deep cycle heat storage and release operation conditions:

[0188] After the conventional shallow heat storage and release process is completed, the hot water storage tank (1) is connected to the primary network water supply pipeline through the fifth valve combination in the plurality of pipeline valve groups, the heat pump unit (15), and the pressure water pump unit (11), and the pressure water pump unit (11) is started to transport the low-temperature water in the tank to the condenser (2) side of the heat pump unit (15) for heat absorption and temperature increase, and then transported to the primary network water supply pipeline for heating, thereby forming a deep circulation heat release water supply pipeline;

[0189] The hot water storage tank (1) is connected to the primary network return water pipeline through the sixth valve combination in the plurality of pipeline valve groups and the heat pump unit (15), and the heat pump unit (15) is started to transport a portion of the low-temperature water in the primary network return water to the evaporator (3) side of the heat pump unit (15) to cool it into even lower temperature water and transport it to fill the bottom of the hot water storage tank (1), thereby forming a deep circulation heat release return water pipeline;

[0190] S3. Set the operation control strategy:

[0191] Based on the unit operation data of the source-side thermal power plant and the operation data of the heat network, combined with external environmental data, date characteristics and user behavior characteristics, the unit heat supply plan of the source-side thermal power plant and the heat demand value of the heat network are obtained;

[0192] Analyze the heat supply and demand relationship between the heat supply plan of the source-side thermal power plant and the heat demand forecast value of the heat network, and set the deep and shallow double-cycle heat storage and release mode of the hot water storage tank according to the heat supply and demand relationship;

[0193] Based on the heat storage and release mode of the initially set hot water storage tank (1), the heat storage water supply pipeline and the heat storage pressurized return water pipeline are first started to store heat in the hot water storage tank (1); when the output of the thermal power plant is insufficient and the hot water storage tank (1) needs to release heat to supplement the heat of the heat network, the conventional shallow heat storage and release operation condition is first entered, the conventional shallow heat release pressurized water supply pipeline and the conventional shallow heat release return water pipeline are started, and the scheduling control strategy of the hot water storage tank (1), the pressurized water pump group (11) and the multiple groups of pipeline valves is generated; when the heat supply value of the unit of the thermal power plant does not meet the heat demand value of the heat network and the heat storage surplus of the hot water storage tank (1) in the conventional shallow heat release mode is insufficient, then after the conventional shallow heat storage and release operation condition is completed, the deep circulation heat storage and release operation condition is entered, the deep circulation heat release water supply pipeline and the deep circulation heat release return water pipeline are started, and the scheduling control strategy of the hot water storage tank (1), the pressurized water pump group (11), the heat pump unit (15) and the multiple groups of pipeline valves is generated.

[0194] In several embodiments provided in the present application, it should be understood that the disclosed system and method can also be implemented in other ways. The system embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the systems, methods and computer program products according to multiple embodiments of the present invention. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, and a part of the module, program segment or code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0195] In addition, the functional modules in each embodiment of the present invention can be integrated together to form an independent part, or each module can exist separately, or two or more modules can be integrated to form an independent part. If the function is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, RandomAccess Memory), disk or optical disk and other media that can store program codes.

[0196] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A deep and shallow dual-mode circulation heat storage tank system based on a heat pump, characterized in that: include: Hot water storage tank, pressure water pump unit, heat pump unit, multiple sets of pipeline valves and dispatch control unit; The hot water storage tank is connected to the primary network water supply pipeline through the first valve combination in the multiple groups of pipeline valves, and the high-temperature water in the primary network water supply pipeline is transported to the top of the hot water storage tank after pressure reduction, so as to form a heat storage water supply pipeline; The hot water storage tank is connected to the primary network return water pipeline through the second valve combination in the multiple groups of pipeline valves and the pressurized water pump group, and the pressurized water pump group is started to pressurize the water at the bottom of the hot water storage tank and then transport it to the primary network return water pipeline to form a heat storage pressurized return water pipeline; The hot water storage tank is connected to the primary network water supply pipeline through the third valve combination in the multiple groups of pipeline valves and the pressurized water pump group. The pressurized water pump group is started to pressurize the high-temperature water at the top of the hot water storage tank and then transport it to the primary network water supply pipeline to form a conventional shallow heat release pressurized water supply pipeline; The hot water storage tank is connected to the primary network return water pipeline through the fourth valve combination in the multiple groups of pipeline valves, and the primary network return water pipeline is used to transport and fill the low-temperature water in the primary network return water to the bottom of the hot water storage tank to form a conventional shallow heat release return water pipeline; The hot water storage tank is connected to the primary network water supply pipeline through the fifth valve combination, the heat pump unit, and the pressure water pump unit in the multiple groups of pipeline valves. The pressure water pump unit and the heat pump unit are started to transport the low-temperature water in the tank to the condenser side of the heat pump unit for heat absorption and temperature increase, and then transported to the primary network water supply pipeline to form a deep circulation heat release water supply pipeline; The hot water storage tank is connected to the primary network return water pipeline through the sixth valve combination in the multiple groups of pipeline valves and the heat pump unit, and the heat pump unit is started to transport a part of the low-temperature water in the primary network return water to the evaporator side of the heat pump unit for cooling into lower temperature water and transporting it to fill the bottom of the hot water storage tank, thereby forming a deep circulation heat release return water pipeline; The dispatch control unit is used to perform a comprehensive analysis of the heat supply and demand relationship based on the heat supplied by the source-side thermal power plant and the heat required by the heat network, combined with the heat storage capacity of the hot water storage tank, and then perform dispatch control of the heat storage water supply pipeline, the heat storage pressurized return water pipeline, the conventional shallow heat release pressurized water supply pipeline, the conventional shallow heat release return water pipeline, the deep circulation heat release water supply pipeline and the deep circulation heat release return water pipeline according to different working conditions, so as to generate a deep-shallow dual-mode dispatch control strategy under the conventional shallow heat storage and release operating conditions and the deep circulation heat storage and release operating conditions.

2. The deep and shallow dual-mode circulation heat storage tank system according to claim 1 is characterized in that: The first valve combination on the heat storage water supply pipeline comprises: opening the thirteenth electric valve (22), the second electric valve (9), the first stop valve (6), and the upper water distribution port (4); the second valve combination on the heat storage pressurized water return pipeline comprises: opening the lower water distribution port (5), the second stop valve (7), the third electric valve (10), the sixth electric valve (14), and the tenth electric valve (19).

3. The deep and shallow dual-mode circulation heat storage tank system according to claim 1 is characterized in that: The third valve combination on the conventional shallow heat release pressurized water supply pipeline comprises: opening the upper water distribution port (4), the first stop valve (6), the first electric valve (8), the sixth electric valve (14), and the eleventh electric valve (20); the fourth valve combination on the conventional shallow heat release return water pipeline comprises: opening the twelfth electric valve (21), the fourteenth electric valve (23), the fourth electric valve (12), the second stop valve (7), and the lower water distribution port (5).

4. The deep and shallow dual-mode circulation heat storage tank system according to claim 1 is characterized in that: The fifth valve combination on the deep circulation heat release water supply pipeline comprises: opening the upper water distribution port (4), the first stop valve (6), the first electric valve (8), the sixth electric valve (14), the eighth electric valve (17), and the seventh electric valve (16); the sixth valve combination on the deep circulation heat release water return pipeline comprises: opening the twelfth electric valve (21), the ninth electric valve (18), the fifth electric valve (13), the fourth electric valve (12), the second stop valve (7), and the lower water distribution port (5).

5. The deep and shallow dual-mode circulation heat storage tank system according to claim 1 is characterized in that: After the heat storage water supply pipeline and the heat storage pressurized return water pipeline are started and operated, the heat storage process begins. The top of the hot water storage tank is filled with high-temperature water and the bottom is filled with low-temperature water. A temperature oblique layer is gradually formed in the middle. The position of the temperature oblique layer gradually moves downward as the heat storage process proceeds until the heat storage is stopped or the heat storage process is completed. After the heat storage process is completed, the hot water storage tank is filled with high-temperature water. After the conventional shallow heat release pressurized water supply pipeline and the conventional shallow heat release return water pipeline are started and run, they enter the shallow cycle heat release process. The top of the hot water storage tank is stored high-temperature water, and the bottom is flowing low-temperature water. A temperature gradient layer is gradually formed in the middle, and the position of the temperature gradient layer gradually moves upward as the heat release process proceeds until the heat release stops or the heat release process is completed. After the shallow cycle heat release process is completed, the hot water storage tank is filled with low-temperature water; After the shallow cycle heat release process is completed and the deep cycle heat release water supply pipeline and the deep cycle heat release return pipeline are started and operated, the deep cycle heat release process is entered. At the beginning of the deep cycle heat release process, the hot water storage tank is low-temperature water, and the return water from the first-level network enters the evaporator of the heat pump unit for cooling to generate lower temperature water and is sent to the bottom of the tank. At the same time, the low-temperature water left at the top of the tank after the shallow cycle heat release is completed is sent to the condenser of the heat pump unit for heating to generate high-temperature water and is sent to the first-level network for water supply. That is, the heat pump unit absorbs the waste heat of part of the return water from the first-level heating network to heat the low-temperature water supplied from the tank, and the heated high-temperature water is sent to the first-level heating network for water supply for continuous deep cycle heat release of the hot water storage tank.

6. The deep and shallow dual-mode circulation heat storage tank system according to claim 1, characterized in that: After a comprehensive analysis of the heat supply and demand relationship based on the heat supplied by the source-side thermal power plant and the heat demanded by the heat network, combined with the heat storage capacity of the hot water storage tank, the heat storage water supply pipeline, the heat storage pressurized return water pipeline, the conventional shallow heat release pressurized water supply pipeline, the conventional shallow heat release return water pipeline, the deep circulation heat release water supply pipeline and the deep circulation heat release return water pipeline are dispatched and controlled according to different working conditions, and a deep-shallow dual-mode dispatching control strategy under conventional shallow heat storage and release operating conditions and deep circulation heat storage and release operating conditions is generated, specifically including: Based on the unit operation data of the source-side thermal power plant and the operation data of the heat network, combined with external environmental data, date characteristics and user behavior characteristics, the unit heat supply plan of the source-side thermal power plant and the heat demand value of the heat network are obtained; Analyze the heat supply and demand relationship between the heat supply plan of the source-side thermal power plant and the heat demand forecast value of the heat network, and make preliminary time-segment settings for the heat storage and release mode of the hot water storage tank based on the heat supply and demand relationship; Based on the initially set heat storage and release mode of the hot water storage tank, the heat storage water supply pipeline and the heat storage pressurized return water pipeline are first started to store heat in the hot water storage tank; when the output of the thermal power plant is insufficient and the hot water storage tank needs to release heat to supplement the heat of the heating network, the conventional shallow heat storage and release operation condition is first entered, and the conventional shallow heat release pressurized water supply pipeline and the conventional shallow heat release return water pipeline are started, and the scheduling control strategy of the hot water storage tank, the pressurized water pump group and multiple groups of pipeline valves is generated; when the unit heat supply value of the thermal power plant does not meet the heat demand value of the heating network and the heat storage amount of the hot water storage tank in the conventional shallow heat release mode is insufficient, then after the conventional shallow heat storage and release operation condition is completed, the deep circulation heat storage and release operation condition is entered, and the deep circulation heat release water supply pipeline and the deep circulation heat release return water pipeline are started, and the scheduling control strategy of the hot water storage tank, the pressurized water pump group, the heat pump unit and multiple groups of pipeline valves is generated.

7. The deep and shallow dual-mode circulation heat storage tank system according to claim 6, characterized in that: Under the conventional shallow heat storage and release operating conditions, with the scheduling control cost, operating energy consumption and supply and demand balance as the optimal goal, a conventional shallow heat storage and release optimization scheduling model is established to decide and output the heat storage and release mode and heat storage and release operating power of the hot water storage tank in different time periods, the operating parameters of the booster water pump group, and the start and stop status and valve opening of multiple groups of pipeline valves; Under the deep cycle heat storage and release operating conditions, a deep cycle heat storage and release optimization scheduling model is established with the optimization of scheduling control cost, operating energy consumption, heat pump unit efficiency and supply and demand balance as the goals, and the decision output is the heat storage and release mode and heat storage and release operating power of the hot water storage tank in different time periods, the operating parameters of the booster water pump group, the operating parameters of the heat pump unit, the start and stop status of multiple groups of pipeline valves and the valve opening.

8. An operation control method of a deep-shallow dual-mode circulation heat storage tank system based on a heat pump, characterized in that: The operation control method is based on the deep-shallow dual-mode circulation heat storage tank system based on a heat pump according to any one of claims 1 to 7, and the operation control method includes: S1. Under conventional shallow heat storage and release operating conditions: The hot water storage tank is connected to the primary network water supply pipeline through the first valve combination in the multiple groups of pipeline valves, and the high-temperature water in the primary network water supply pipeline is transported to the top of the hot water storage tank after the pressure is reduced, so as to form a heat storage water supply pipeline; The hot water storage tank is connected to the primary network return water pipeline through the second valve combination in the multiple groups of pipeline valves and the pressurized water pump group, and the pressurized water pump group is started to pressurize the water at the bottom of the hot water storage tank and then transport it to the primary network return water pipeline to form a heat storage pressurized return water pipeline; The hot water storage tank is connected to the primary network water supply pipeline through the third valve combination in the multiple groups of pipeline valves and the pressure water pump group, and the pressure water pump group is started to pressurize the high-temperature water on the top of the hot water storage tank and then transport it to the primary network water supply pipeline to form a conventional shallow heat release pressure water supply pipeline; The hot water storage tank is connected to the primary network return water pipeline through the fourth valve combination in the multiple groups of pipeline valves, and the low-temperature water in the heat network return water is transported and filled to the bottom of the hot water storage tank by the primary network return water pipeline to form a conventional shallow heat release return water pipeline; S2. Under deep cycle heat storage and release operation conditions: After the conventional shallow heat storage and release process is completed, the hot water storage tank is connected to the primary network water supply pipeline through the fifth valve combination, the heat pump unit, and the pressure water pump unit in the multiple groups of pipeline valves, and the pressure water pump unit and the heat pump unit are started to transport the low-temperature water in the tank to the condenser side of the heat pump unit for heat absorption and temperature increase, and then transported to the primary network water supply pipeline for heating, forming a deep circulation heat release water supply pipeline; The hot water storage tank is connected to the primary network return water pipeline through the sixth valve combination in the multiple groups of pipeline valves, the heat pump unit, and the heat pump unit is started to transport a part of the low-temperature water in the primary network return water to the evaporator side of the heat pump unit to cool it into lower temperature water and transport it to fill the bottom of the hot water storage tank, thereby forming a deep circulation heat release return water pipeline; S3. Set the operation control strategy: Based on the unit operation data of the source-side thermal power plant and the operation data of the heat network, combined with external environmental data, date characteristics and user behavior characteristics, the unit heat supply plan of the source-side thermal power plant and the heat demand value of the heat network are obtained; Analyze the heat supply and demand relationship between the heat supply plan of the source-side thermal power plant and the heat demand forecast value of the heat network, and set the deep and shallow double-cycle heat storage and release mode of the hot water storage tank according to the heat supply and demand relationship; Based on the initially set heat storage and release mode of the hot water storage tank, the heat storage water supply pipeline and the heat storage pressurized return water pipeline are first started to store heat in the hot water storage tank; when the output of the thermal power plant is insufficient and the hot water storage tank needs to release heat to supplement the heat of the heating network, the conventional shallow heat storage and release operation condition is first entered, and the conventional shallow heat release pressurized water supply pipeline and the conventional shallow heat release return water pipeline are started, and the scheduling control strategy of the hot water storage tank, the pressurized water pump group and multiple groups of pipeline valves is generated; when the unit heat supply value of the thermal power plant does not meet the heat demand value of the heating network and the heat storage amount of the hot water storage tank in the conventional shallow heat release mode is insufficient, then after the conventional shallow heat storage and release operation condition is completed, the deep circulation heat storage and release operation condition is entered, and the deep circulation heat release water supply pipeline and the deep circulation heat release return water pipeline are started, and the scheduling control strategy of the hot water storage tank, the pressurized water pump group, the heat pump unit and multiple groups of pipeline valves is generated.

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