Energy-saving immersion type cooling system for power supply cable and control method of energy-saving immersion type cooling system

Abstract

According to the energy-saving immersion type cooling system for the power supply cable and the control method of the energy-saving immersion type cooling system, the heat pump unit and the soil heat exchanger are used for obtaining cooling capacity from constant-temperature soil in summer so that the cooling requirement of the cable can be met, and the refrigeration load of the heat pump unit in spring and autumn is relieved through the front cooling tower; the cold storage mode is used for obtaining cold energy from cold air in winter and storing the cold energy, so that the refrigeration requirement in summer is met, cold energy dispatching optimization under the whole-year size is achieved, and finally the purpose of whole-year energy-saving operation of the system is achieved. According to the invention, the cooling requirements of the power supply cable in different seasons are fully considered, and the energy consumption of the energy-saving immersion type cooling system for the power supply cable can be greatly reduced.

Description

Technical Field

[0001] The technical field involved in the present invention particularly relates to an energy-saving immersion cooling system for power supply cables and its control method. Background Art

[0002] With the acceleration of the urbanization process, the demand for electricity is continuously increasing, and the laying of cables is becoming more and more extensive. During the operation of power cables, heat is generated, and as the transmission load increases, the heat generation also increases accordingly. However, long-term high temperature will not only accelerate the aging process of cable materials, shorten the service life of the cables, but also cause damage to the insulation layer, increasing the risks of short circuits and fires. In addition, high temperature will affect the electrical performance of the cables, thus reducing the power transmission efficiency of the cables.

[0003] Therefore, in order to ensure the power transmission efficiency, safe operation and service life of power cables, cooling measures need to be taken to reduce the temperature of the cables. The cooling methods are mainly divided into natural cooling and active cooling: natural cooling mainly relies on the heat dissipation ability of natural environments such as air, and reduces the temperature through convection and radiation heat dissipation on the surface of the cables; active cooling uses additional cooling equipment or media to accelerate the heat dissipation process of the cables. However, with the construction of infrastructure such as cable tunnels and underground utility tunnels, the laying sites of power cables have changed from outdoor overhead to underground laying. Due to the limited ventilation conditions in underground spaces, the natural cooling method is not sufficient to support the heat dissipation requirements of power supply cables, and the active cooling technology for cables has gradually attracted attention.

[0004] The commonly used active cooling technology for cables is mainly forced air cooling technology, that is, jet fans or impellers and other equipment are used in cable tunnels to strengthen air flow and enhance the convective heat transfer effect on the surface of the cables. However, in some special places, such as long-distance cross-river cable tunnels, the forced air cooling scheme is not applicable.

[0005] In the existing technology, "a green and environment-friendly power supply cable heat dissipation device" (CN 119092207A) has been disclosed for dissipating heat from power supply cables. This invention provides a green and environment-friendly power supply cable heat dissipation device, including components such as heat dissipation fins, cooling pipes and a water circulation system. The cooling pipes are wound around the outside of the power supply cables, and a coolant (in the refrigeration field, the refrigerant is called chilled water) flows inside, absorbing the heat dissipated from the surface of the cables through heat conduction, thereby realizing the cooling work of the power supply cables. Obviously, in the patent "a green and environment-friendly power supply cable heat dissipation device" (CN 119092207A), the low-temperature chilled water is an important medium for cable cooling. However, this patent does not explain the source of the chilled water, that is, it does not answer the questions of "where does the cold in the chilled water come from" or "how to prepare low-temperature chilled water".

[0006] In summary, the good heat dissipation of power cables is crucial for their safe, stable, and efficient operation. Especially in environments with poor ventilation such as underground cable tunnels, traditional natural cooling is often insufficient to meet the heat dissipation requirements. Although forced air cooling technology can enhance the heat dissipation effect to a certain extent, its effect is limited for special places such as long-distance cross-river cable tunnels. In contrast, water cooling technology provides a more ideal heat dissipation solution by circulating chilled water to efficiently absorb heat. However, there is still no invention in cable water cooling technology that can effectively solve the two problems of "where does the cold in chilled water come from" and "the huge energy consumption in chilled water preparation". Therefore, optimizing water cooling technology, improving energy efficiency, and solving the problem of cold source are the keys to promoting the further development of this technology. Summary of the Invention

[0007] The object of the present invention is to provide an energy-saving immersion cooling system for power supply cables and its control method to solve the cable heat dissipation problem and reduce the energy consumption of the water cooling system.

[0008] To achieve the above object, the present invention adopts the following technical solutions:

[0009] An energy-saving immersion cooling system for power supply cables, which is used to provide multi-mode energy-saving temperature reduction for the cables, including a refrigeration mode, an energy-saving mode, and a cold storage mode;

[0010] The refrigeration mode includes a heat pump unit, a cooling pipe, a chilled water supply and return main pipe, a soil heat exchanger, and a cooling water supply and return main pipe;

[0011] The heat pump unit is arranged between the cooling pipe and the soil heat exchanger for preparing chilled water;

[0012] The cooling pipe is sleeved outside the cable and forms a space for storing chilled water with the cable, for adsorbing the heat energy of the cable;

[0013] The chilled water supply and return main pipe connects the cooling pipe and the heat pump unit to form a first chilled water loop;

[0014] The soil heat exchanger is arranged in the underground constant temperature soil layer; the heat pump unit is connected to the soil heat exchanger through the cooling water supply and return main pipe to form a first cooling water loop;

[0015] The energy-saving mode includes a pre-cooling tower and a chilled water supply and return branch pipe. The chilled water in the pre-cooling tower exchanges heat with the outdoor air for temperature reduction, and the chilled water supply and return branch pipe and the pre-cooling tower form a second chilled water loop with the cooling pipe;

[0016] The cold storage mode includes a rear cooling tower and cooling water supply and return branch pipes. The rear cooling tower obtains cold energy from the outdoor low-temperature air to prepare low-temperature cooling water. The rear cooling tower and the cooling water supply and return branch pipes form a second cooling water circuit with the soil heat exchanger.

[0017] Preferably, the chilled water supply and return main pipes include a chilled water supply main pipe and a chilled water return main pipe; both ends of the chilled water supply main pipe are respectively connected to the water inlet end of the cooling pipe and the water outlet end of the heat pump unit; both ends of the chilled water return main pipe are respectively connected to the water outlet end of the cooling pipe and the water inlet end of the heat pump unit;

[0018] The cooling water supply and return main pipes include a cooling water supply main pipe and a cooling water return main pipe; both ends of the cooling water supply main pipe are respectively connected to the water inlet end of the heat pump unit and the water outlet end of the soil heat exchanger; both ends of the cooling water return main pipe are respectively connected to the water outlet end of the heat pump unit and the water inlet end of the soil heat exchanger.

[0019] Preferably, the switching between the first chilled water circuit and the second chilled water circuit is controlled by a three-way valve; the switching between the first cooling water circuit and the second cooling water circuit is controlled by a three-way valve.

[0020] Preferably, the chilled water supply and return branch pipes include a chilled water supply branch pipe and a chilled water return branch pipe; a three-way valve one is provided between the chilled water supply branch pipe and the chilled water supply main pipe; a three-way valve two is provided between the chilled water return branch pipe and the chilled water return main pipe; the first chilled water circuit or the second chilled water circuit is switched by adjusting the three-way valve one and the three-way valve two simultaneously.

[0021] Preferably, the cooling water supply and return branch pipes include a cooling water supply branch pipe and a cooling water return branch pipe; a three-way valve three is provided between the cooling water supply branch pipe and the cooling water supply main pipe; a three-way valve four is provided between the cooling water return branch pipe and the cooling water return main pipe; the first cooling water circuit or the second cooling water circuit is switched by adjusting the three-way valve three and the three-way valve four simultaneously.

[0022] The present invention also provides a control method for an energy-saving immersion cooling system based on a power supply cable, including a refrigeration mode, an energy-saving mode, and a cold storage mode; the adjustment method is as follows:

[0023] Step S0: It is preset that the system turns on the refrigeration mode in summer, the energy-saving mode in spring and autumn, and the cold storage mode in winter;

[0024] Step S1: First, by monitoring the outdoor ambient temperature and combining with the calendar module, the current season is identified;

[0025] Step S2: The corresponding mode is turned on according to the identified season

[0026] Cooling mode: When it is recognized as summer, the temperature is high in summer, the natural heat dissipation effect of the power supply cable is poor, the water temperature of the chilled water required by the cable is low, and the system turns on the cooling mode;

[0027] The control system opens the chilled water supply and return main pipes and closes the chilled water supply and return branch pipes by adjusting the first three-way valve and the second three-way valve simultaneously, so as to form a first chilled water loop between the cooling pipe, the chilled water supply and return main pipes and the heat pump unit;

[0028] At the same time, the control system opens the cooling water supply and return main pipes and closes the cooling water supply and return branch pipes by adjusting the third three-way valve and the fourth three-way valve simultaneously, and a first cooling water loop is formed between the heat pump unit and the ground heat exchanger;

[0029] Then start the ground heat exchanger. The ground heat exchanger extracts cold from the constant temperature soil layer through the cooling water supply main pipe, prepares cooling water, and transports it to the heat pump unit through the cooling water return main pipe;

[0030] Start the heat pump unit at the same time. Prepare low-temperature chilled water and transport it to the cooling pipe through the chilled water supply main pipe, so that the space between the cooling pipe and the cable is filled with low-temperature chilled water. The chilled water submerges the cable and absorbs the heat dissipated from the cable surface, prompting the cable temperature to decrease; then the chilled water after absorbing heat is returned to the heat pump unit through the chilled water return main pipe;

[0031] Energy-saving mode: When it is recognized as spring and autumn, the temperature is moderate in spring and autumn, the natural heat dissipation effect of the power supply cable is average, the water temperature of the chilled water required by the cable is moderate, close to normal temperature water, and the system turns on the energy-saving mode;

[0032] First, close the chilled water supply and return main pipes and open the chilled water supply and return branch pipes by adjusting the first three-way valve and the second three-way valve, so as to form a second chilled water loop between the cooling pipe and the pre-cooling tower through the chilled water supply and return branch pipes;

[0033] Then start the pre-cooling tower. At this time, the heat pump unit remains closed. The chilled water in the pre-cooling tower exchanges heat with the outdoor air to cool down; the cooled chilled water is filled into the cooling pipe from the pre-cooling tower through the chilled water supply branch pipe, submerges the cable and absorbs the heat dissipated from the cable surface, prompting the cable temperature to decrease; then the chilled water after absorbing heat is returned to the pre-cooling tower through the chilled water return branch pipe to continue exchanging heat with the outdoor air to cool down;

[0034] Cold storage mode: The temperature is low in winter, the natural heat dissipation effect of the power supply cable is strong, and the cable has no water cooling demand. The system turns on the cold storage mode; first, close the cooling water supply and return main pipes and open the cooling water supply and return branch pipes by adjusting the three-way valve and, so as to form a second cooling water loop between the ground heat exchanger and the post-cooling tower through the cooling water supply and return branch pipes;

[0035] Then start the rear cooling tower. The rear cooling tower obtains cold energy from the low-temperature outdoor air to prepare low-temperature cooling water. The low-temperature cooling water is transported through the cooling water supply branch pipe to the soil heat exchanger to exchange heat with the constant-temperature soil layer, transfer the cold energy to the constant-temperature soil layer and store it for the system refrigeration mode to call during the summer; the cooling water supply branch pipe after heat exchange; then the cooled water is returned to the rear cooling tower through the cooling water return branch pipe to continue obtaining cold energy from the low-temperature outdoor air.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] (1) The present invention uses a heat pump unit to prepare chilled water and adopts an immersion water cooling technology to cool the power supply cable to meet the cooling requirements of the power supply cable, solving the problem of "how to prepare chilled water for the cable water cooling technology".

[0038] (2) The present invention uses a soil heat exchanger to obtain cold energy from the constant-temperature soil layer to greatly reduce the energy consumption for preparing chilled water, alleviating the problem of "high refrigeration energy consumption of the cable water cooling system".

[0039] (3) In view of the problem that the cooling requirements of the power supply cable are different in different seasons, the present invention proposes three system operation modes: refrigeration mode, energy-saving mode, and cold storage mode. During the summer, the cooling requirement of the cable is the largest, and the system adopts the refrigeration mode; during the spring and autumn, the cooling requirement of the cable decreases, and the system adopts the energy-saving mode, using the front cooling tower to replace the heat pump unit to prepare chilled water to reduce the system energy consumption; during the winter, the cable has no water cooling requirement, and the system adopts the cold storage mode, obtaining cold energy from the outdoor cold air through the rear cooling tower and storing it in the underground constant-temperature soil layer to meet the refrigeration requirements in summer. The present invention obtains cold energy from the constant-temperature soil by using a heat pump unit and a soil heat exchanger in summer to meet the cooling requirements of the cable, uses the front cooling tower to reduce the refrigeration load of the heat pump unit in spring and autumn, and uses the cold storage mode to obtain and store cold energy from the winter cold air to meet the refrigeration requirements in summer, realizing the optimization of cold energy scheduling throughout the year and ultimately achieving the goal of the system's annual energy-saving operation. The present invention fully considers the cooling requirements of the power supply cable in different seasons and can greatly reduce the energy consumption of the energy-saving immersion cooling system for power supply cables. Description of the Drawings

[0040] Figure 1 It is a schematic diagram of the working principle of an energy-saving immersion cooling system for power supply cables provided by an embodiment of the present invention;

[0041] Figure 2 It is a flowchart of the energy-saving control strategy of an energy-saving immersion cooling system for power supply cables provided by an embodiment of the present invention.

[0042] The serial numbers in the figure are as follows:

[0043] 1. Heat pump unit; 2. Cooling pipe; 3. Chilled water supply and return main pipe; 4. Front cooling tower; 5. Chilled water supply and return branch pipe; 6. Soil heat exchanger; 7. Cooling water supply and return main pipe; 8. Rear cooling tower; 9. Cooling water supply and return branch pipe; 10-1. Three-way valve one; 10-2. Three-way valve two; 10-3. Three-way valve three; 10-4. Three-way valve four. Specific embodiments

[0044] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0045] As Figure 1 shown, a power supply cable energy-saving immersion cooling system provided in this embodiment is used to provide multi-mode energy-saving cooling for the cable. Aiming at the problem that the cooling requirements of the power supply cable are different in different seasons, three system operation modes of a refrigeration mode, an energy-saving mode, and a cold storage mode are proposed.

[0046] The refrigeration mode includes a heat pump unit 1, a cooling pipe 2, a chilled water supply and return main pipe 3, a soil heat exchanger 6, and a cooling water supply and return main pipe 7.

[0047] The heat pump unit 1 is arranged between the cooling pipe 2 and the soil heat exchanger 6 and is used to prepare chilled water.

[0048] The cooling pipe 2 is sleeved outside the cable and forms a space for storing chilled water with the cable, and is used to adsorb the heat energy of the cable.

[0049] The chilled water supply and return main pipe 3 includes a chilled water supply main pipe and a chilled water return main pipe; both ends of the chilled water supply main pipe are respectively connected to the water inlet end of the cooling pipe 2 and the water outlet end of the heat pump unit 1; both ends of the chilled water return main pipe are respectively connected to the water outlet end of the cooling pipe 2 and the water inlet end of the heat pump unit 1, forming a first chilled water circuit, which is used to transport the chilled water in the heat pump unit 1 to the space and send the heat-absorbed chilled water back to the heat pump unit 1. In this embodiment, the heat pump unit 1 is used to prepare chilled water, and the immersion water cooling technology is adopted to cool the cable to meet the cooling requirements of the power supply cable, and the problem of "how to prepare chilled water for the cable water cooling technology" is solved.

[0050] The soil heat exchanger 6 is arranged in the underground constant-temperature soil layer; the heat pump unit 1 is connected to the soil heat exchanger 6 through the cooling water supply and return main pipes 7, and the cooling water supply and return main pipes 7 include a cooling water supply main pipe and a cooling water return main pipe; both ends of the cooling water supply main pipe are respectively connected to the water inlet end of the heat pump unit 1 and the water outlet end of the soil heat exchanger 6; both ends of the cooling water return main pipe are respectively connected to the water outlet end of the heat pump unit 1 and the water inlet end of the soil heat exchanger 6, forming a first cooling water circuit for delivering the high-temperature cooling water of the heat pump unit 1 to the soil heat exchanger 6, releasing heat through the heat exchange of the soil, and re-preparing the cooling water. In this embodiment, the soil heat exchanger is used to obtain cold energy from the constant-temperature soil layer, so as to greatly reduce the energy consumption for preparing chilled water and alleviate the problem of "high refrigeration energy consumption of the cable water cooling system".

[0051] The energy-saving mode includes a pre-cooling tower 4 and a chilled water supply and return branch pipe 5. The chilled water in the pre-cooling tower 4 exchanges heat with the outdoor air to cool down, and the chilled water supply and return branch pipe 5 and the pre-cooling tower 4 form a second chilled water circuit with the cooling pipe 2.

[0052] The cold storage mode includes a post-cooling tower 8 and a cooling water supply and return branch pipe 9. The post-cooling tower 8 obtains cold energy from the outdoor low-temperature air to prepare low-temperature cooling water, and the post-cooling tower 8 and the cooling water supply and return branch pipe 9 form a second cooling water circuit with the soil heat exchanger 6.

[0053] Furthermore, in this embodiment, the chilled water supply and return branch pipe 5 includes a chilled water supply branch pipe and a chilled water return branch pipe; a three-way valve 10-1 is provided between the chilled water supply branch pipe and the chilled water supply main pipe; a three-way valve 10-2 is provided between the chilled water return branch pipe and the chilled water return main pipe; the three-way valve 10-1 and the three-way valve 10-2 are adjusted simultaneously to switch between the first chilled water circuit and the second chilled water circuit. The cooling water supply and return branch pipe 9 includes a cooling water supply branch pipe and a cooling water return branch pipe; a three-way valve 10-3 is provided between the cooling water supply branch pipe and the cooling water supply main pipe; a three-way valve 10-4 is provided between the cooling water return branch pipe and the cooling water return main pipe; the three-way valve 10-3 and the three-way valve 10-4 are adjusted simultaneously to switch between the first cooling water circuit and the second cooling water circuit.

[0054] This embodiment provides a control method for the power supply cable energy-saving immersion cooling system, including a refrigeration mode, an energy-saving mode, and a cold storage mode; the adjustment method is as follows:

[0055] Step S0: Preset that the system turns on the refrigeration mode in summer, the energy-saving mode in spring and autumn, and the cold storage mode in winter;

[0056] Step S1: First, by monitoring the outdoor ambient temperature and combining with the calendar module, identify the current season;

[0057] Step S2: Turn on the corresponding mode according to the recognized season

[0058] Refrigeration mode: When it is recognized as summer, the temperature is high in summer, the natural heat dissipation effect of the power supply cable is poor, the water temperature of the chilled water required by the cable is low, and the system turns on the refrigeration mode;

[0059] The control system turns on the chilled water supply and return main pipe 3 and closes the chilled water supply and return branch pipe 5 by adjusting the first three-way valve 10-1 and the second three-way valve 10-2 at the same time, so as to form a first chilled water loop between the cooling pipe 2, the chilled water supply and return main pipe 3 and the heat pump unit 1;

[0060] At the same time, the control system turns on the cooling water supply and return main pipe 7 and closes the cooling water supply and return branch pipe 9 by adjusting the third three-way valve 10-3 and the fourth three-way valve 10-4 at the same time, and a first cooling water loop is formed between the heat pump unit 1 and the ground heat exchanger 6;

[0061] Then start the ground heat exchanger 6. The ground heat exchanger 6 extracts cold energy from the constant temperature soil layer through the cooling water supply main pipe, prepares cooling water, and transports it to the heat pump unit 1 through the cooling water return main pipe;

[0062] At the same time, start the heat pump unit 1, prepare low-temperature chilled water and transport it to the cooling pipe 2 through the chilled water supply main pipe, so that the space between the cooling pipe 2 and the cable is filled with low-temperature chilled water. The chilled water submerges the cable and absorbs the heat dissipated from the cable surface, promoting the cable temperature to decrease; then the heat-absorbed chilled water is returned to the heat pump unit 1 through the chilled water return main pipe;

[0063] Energy-saving mode: When it is recognized as spring and autumn, the temperature is moderate in spring and autumn, the natural heat dissipation effect of the power supply cable is average, the water temperature of the chilled water required by the cable is moderate, close to normal temperature water, and the system turns on the energy-saving mode;

[0064] First, by adjusting the first three-way valve 10-1 and the second three-way valve 10-2, close the chilled water supply and return main pipe 3 and open the chilled water supply and return branch pipe 5, so that the cooling pipe 2 forms a second chilled water loop with the pre-cooling tower 4 through the chilled water supply and return branch pipe 5;

[0065] Then start the pre-cooling tower 4. At this time, the heat pump unit 1 remains closed. The chilled water in the pre-cooling tower 4 exchanges heat with the outdoor air to cool down; the cooled chilled water is filled into the cooling pipe 2 from the pre-cooling tower 4 through the chilled water supply branch pipe, submerges the cable and absorbs the heat dissipated from the cable surface, promoting the cable temperature to decrease; then the heat-absorbed chilled water is returned to the pre-cooling tower 4 through the chilled water return branch pipe and continues to exchange heat with the outdoor air to cool down;

[0066] Cool storage mode: In winter, the temperature is low, and the natural heat dissipation effect of the power supply cable is strong. There is no need for water cooling to cool the cable, so the system enters the cool storage mode. First, by adjusting the three-way valves 10-3 and 10-4, the cooling water supply and return main pipes 7 are closed, and the cooling water supply and return branch pipes 9 are opened, so that a second cooling water circuit is formed between the soil heat exchanger 6 and the rear cooling tower 8 through the cooling water supply and return branch pipes 9.

[0067] Then start the rear cooling tower 8. The rear cooling tower 8 obtains cold energy from the low-temperature outdoor air to prepare low-temperature cooling water. The low-temperature cooling water is transported to the soil heat exchanger 6 through the cooling water supply branch pipe to exchange heat with the constant-temperature soil layer, transfer the cold energy to the constant-temperature soil layer and store it for use in the refrigeration mode of the system during summer. The cooling water supply branch pipe after heat exchange; then the cooled cooling water is returned to the rear cooling tower 8 through the cooling water return branch pipe to continue obtaining cold energy from the low-temperature outdoor air.

[0068] In this embodiment, according to the summer period, the cooling demand of the cable is the largest, and the system adopts the refrigeration mode; in the spring and autumn periods, the cooling demand of the cable decreases, and the system adopts the energy-saving mode, using the front cooling tower to replace the heat pump unit to prepare chilled water to reduce the system energy consumption; in the winter period, there is no need for water cooling to cool the cable, and the system adopts the cool storage mode, obtaining cold energy from the outdoor cold air through the rear cooling tower and storing it in the underground constant-temperature soil layer to meet the refrigeration demand in summer.

[0069] In this embodiment, in summer, the heat pump unit and the soil heat exchanger are used to obtain cold energy from the constant-temperature soil to meet the cooling demand of the cable. The front cooling tower is used to reduce the refrigeration load of the heat pump unit in spring and autumn. The cool storage mode is used to obtain and store cold energy from the winter cold air to meet the refrigeration demand in summer, realizing the optimization of cold energy scheduling throughout the year, and finally achieving the goal of the system's energy-saving operation throughout the year. The present invention fully considers the cooling demand of the power supply cable in different seasons and can greatly reduce the energy consumption of the energy-saving immersion cooling system for power supply cables.

[0070] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0071] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality of" means two or more unless otherwise specifically defined.

[0072] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes, should be covered by the protection scope of the present invention.

Claims

1. An energy-saving immersion cooling system for power supply cables, used to provide multi-mode energy-saving and cooling for cables, characterized in that: Including cooling mode, energy-saving mode and cold storage mode; The refrigeration mode comprises a heat pump unit (1), a cooling pipe (2), a chilled water supply and return main pipe (3), a soil heat exchanger (6), and a cooling water supply and return main pipe (7); The heat pump unit (1) is arranged between the cooling pipe (2) and the soil heat exchanger (6) and is used to prepare chilled water; The cooling pipe (2) is sleeved on the outside of the cable and forms a space for storing chilled water between the cooling pipe and the cable for absorbing heat energy from the cable; The chilled water supply and return main pipe (3) connects the cooling pipe (2) and the heat pump unit (1) to form a first chilled water circuit; The soil heat exchanger (6) is arranged in an underground constant temperature soil layer; the heat pump unit (1) is connected to the soil heat exchanger (6) via the cooling water supply and return water main pipe (7) to form a first cooling water loop; The energy-saving mode includes a front cooling tower (4) and a chilled water supply and return branch pipe (5), the chilled water in the front cooling tower (4) exchanges heat with outdoor air for cooling, and the chilled water supply and return branch pipe (5) and the front cooling tower (4) form a second chilled water circuit with the cooling pipe (2); The cold storage mode includes a rear cooling tower (8) and a cooling water supply and return branch pipe (9). The rear cooling tower (8) obtains cold energy from outdoor low-temperature air to prepare low-temperature cooling water. The rear cooling tower (8) and the cooling water supply and return branch pipe (9) form a second cooling water loop with the soil heat exchanger (6).

2. The energy-saving immersion cooling system for power supply cables according to claim 1, characterized in that: The chilled water supply and return main pipe (3) comprises a chilled water supply main pipe and a chilled water return main pipe; the two ends of the chilled water supply main pipe are respectively connected to the water inlet end of the cooling pipe (2) and the water outlet end of the heat pump unit (1); the two ends of the chilled water return main pipe are respectively connected to the water outlet end of the cooling pipe (2) and the water inlet end of the heat pump unit (1); The cooling water supply and return main pipe (7) comprises a cooling water supply main pipe and a cooling water return main pipe; the two ends of the cooling water supply main pipe are respectively connected to the water inlet end of the heat pump unit (1) and the water outlet end of the soil heat exchanger (6); the two ends of the cooling water return main pipe are respectively connected to the water outlet end of the heat pump unit (1) and the water inlet end of the soil heat exchanger (6).

3. The energy-saving immersion cooling system for power supply cables according to claim 2, characterized in that: The first chilled water circuit and the second chilled water circuit are switched by a three-way valve; the first cooling water circuit and the second cooling water circuit are switched by a three-way valve.

4. The energy-saving immersion cooling system for power supply cables according to claim 3 is characterized in that: The chilled water supply and return branch pipes include a chilled water supply branch pipe and a chilled water return branch pipe; a three-way valve one (10-1) is provided between the chilled water supply branch pipe and the chilled water supply main pipe; a three-way valve two (10-2) is provided between the chilled water return branch pipe and the chilled water return main pipe; and the three-way valve one (10-1) and the three-way valve two (10-2) are adjusted simultaneously to switch the first chilled water circuit or the second chilled water circuit.

5. The energy-saving immersion cooling system for power supply cables according to claim 3, characterized in that: The cooling water supply and return branch pipes include a cooling water supply branch pipe and a cooling water return branch pipe; a three-way valve three (10-3) is provided between the cooling water supply branch pipe and the cooling water supply main pipe; a three-way valve four (10-4) is provided between the cooling water return branch pipe and the cooling water return main pipe; and the three-way valve three (10-3) and the three-way valve four (10-4) are adjusted simultaneously to switch the first cooling water circuit or the second cooling water circuit.

6. A control method for the energy-saving immersion cooling system of a power supply cable based on claims 1-5, characterized in that: Including cooling mode, energy-saving mode and cold storage mode; the adjustment methods are as follows: Step S0: The system is preset to start cooling mode in summer, energy-saving mode in spring and autumn, and cold storage mode in winter; Step S1: First, the current season is identified by monitoring the outdoor ambient temperature and combining with the calendar module; Step S2: Enable the corresponding mode according to the identified season Cooling mode: When it is recognized as summer, the temperature is high in summer, the natural heat dissipation effect of the power supply cable is poor, and the temperature of the chilled water required by the cable is low, so the system turns on the cooling mode; The control system simultaneously adjusts the three-way valve 1 (10-1) and the three-way valve 2 (10-2) to open the chilled water supply and return main pipe (3) and close the chilled water supply and return branch pipe (5), so that a first chilled water loop is formed between the cooling pipe (2), the chilled water supply and return main pipe (3) and the heat pump unit (1); At the same time, the control system opens the cooling water supply and return water main pipe (7) and closes the cooling water supply and return water branch pipe (9) by simultaneously adjusting the three-way valve three (10-3) and the three-way valve four (10-4), thereby forming a first cooling water loop between the heat pump unit (1) and the soil heat exchanger (6); Then, the soil heat exchanger (6) is started, and the soil heat exchanger (6) extracts cold from the constant temperature soil layer through the cooling water supply main pipe, prepares cooling water, and transports the cooling water to the heat pump unit (1) through the cooling water return main pipe; At the same time, the heat pump unit (1) is started to prepare low-temperature chilled water, which is transported to the cooling pipe (2) through the chilled water supply main pipe, so that the space between the cooling pipe (2) and the cable is filled with low-temperature chilled water, and the chilled water immerses the cable and absorbs the heat dissipated on the surface of the cable, thereby causing the cable temperature to decrease; The chilled water after absorbing heat is then returned to the heat pump unit (1) through the chilled water return main pipe; Energy-saving mode: When it is identified as spring and autumn, the temperature in spring and autumn is moderate, the natural heat dissipation effect of the power supply cable is average, and the temperature of the chilled water required by the cable is moderate, close to normal temperature water, and the system turns on the energy-saving mode; First, by adjusting the three-way valve 1 (10-1) and the three-way valve 2 (10-2), the chilled water supply and return main pipe (3) is closed, and the chilled water supply and return branch pipe (5) is opened, so that the cooling pipe (2) passes through the chilled water supply and return branch pipe (5) and forms a second chilled water loop between the front cooling tower (4); Then, the front cooling tower (4) is started, while the heat pump unit (1) remains in a closed state, and the chilled water in the front cooling tower (4) exchanges heat with the outdoor air to cool down; the chilled water after cooling is poured from the front cooling tower (4) into the cooling pipe (2) through the chilled water supply branch pipe, submerging the cable and absorbing the heat dissipated on the surface of the cable, thereby lowering the cable temperature; The chilled water after absorbing heat is then returned to the front cooling tower (4) through the chilled water return branch pipe to continue to exchange heat with the outdoor air for cooling; Cold storage mode: In winter, the temperature is low, the natural heat dissipation effect of the power supply cable is strong, and the cable does not need water cooling, so the system starts the cold storage mode; first, by adjusting the three-way valves (10-3) and (10-4), the cooling water supply and return water main pipe (7) is closed, and the cooling water supply and return water branch pipe (9) is opened, so that the soil heat exchanger (6) forms a second cooling water loop through the cooling water supply and return water branch pipe (9) and the rear cooling tower (8); Then, the rear cooling tower (8) is started, and the rear cooling tower (8) obtains cold energy from the outdoor low-temperature air to prepare low-temperature cooling water. The low-temperature cooling water is transported to the soil heat exchanger (6) through the cooling water supply branch pipe to exchange heat with the constant-temperature soil layer, and the cold energy is transferred to the constant-temperature soil layer and stored so that the system cooling mode can be called in the summer period; the cooling water supply branch pipe after heat exchange; and the cooling water after heat exchange is returned to the rear cooling tower (8) through the cooling water return branch pipe to continue to obtain cold energy from the outdoor low-temperature air.

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