An in-situ geothermal power generation system

Abstract

The present invention provides an in-situ geothermal power generation system, comprising a heat pipe, a thermoelectric thermoelectric generator, and a magnetic levitation generator. The upper end of the heat pipe extends to the ground surface or a body of water, and the lower end of the heat pipe is located at a geothermal source. A circulation cavity is formed within the heat pipe, and a circulating working medium is disposed within the circulation cavity. The thermoelectric thermoelectric generator is located at the lower end of the heat pipe, and the magnetic levitation generator is located in the middle of the heat pipe. The thermoelectric thermoelectric generator and the magnetic levitation generator output electrical energy through an electrical energy output port. This system directly buries the heat pipe deep underground, with the heat pipe located at the geothermal source. On the one hand, the thermoelectric thermoelectric generator located at the lower end of the heat pipe can directly convert geothermal energy into electrical energy. On the other hand, during the phase transition of the circulating working medium into a gaseous working medium, the upward-flowing gaseous working medium drives the magnetic levitation generator located in the middle of the heat pipe, converting the geothermal energy into mechanical energy and then into electrical energy. This system has the advantages of in-situ geothermal power generation, low energy loss, and high power generation efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of geothermal power generation, in particular to a system for generating electricity using geothermal energy, and in particular to an in-situ geothermal power generation system for directly generating electricity using geothermal energy. Background Art

[0002] As industrialization progresses, accompanied by a rapid increase in energy consumption, energy crises and environmental pollution are becoming increasingly severe. Energy challenges will become even more prominent in the foreseeable future, prompting countries around the world to explore the development and utilization of renewable energy. Geothermal energy is renewable heat energy derived from deep within the Earth, primarily from molten magma and the decay of radioactive materials. The Earth's interior reaches temperatures as high as 7,000°C, and when heat is transferred to the crust closer to the surface, it still retains considerable energy. Compared to other energy sources, geothermal energy resources offer advantages such as abundant reserves, clean and environmentally friendly properties, and renewable nature. Therefore, utilizing geothermal energy for power generation is a key area of clean energy development.

[0003] In existing technologies, the use of geothermal energy requires transferring geothermal energy to the surface via certain specific carriers, and then further converting and utilizing it on this basis. For example, hot water heated by geothermal energy can be extracted from the ground through a water cycle, and then the geothermal energy is absorbed by the water, and the thermal energy of the hot water is used to generate electricity. As you can imagine, this type of solution can only utilize geothermal energy indirectly, requiring geothermal energy to be transferred above the ground via a carrier, which will cause great losses in the process, and there are problems such as difficulty in energy extraction, high energy loss, and low power generation efficiency. Due to the above problems, the current proportion of geothermal power generation is very small, and the power generation method urgently needs to be broken through.

[0004] Therefore, the existing technology still needs to be improved and developed. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide an in-situ geothermal power generation system in response to the above-mentioned defects of the prior art, which directly utilizes geothermal energy for in-situ power generation and has the advantages of no need for energy extraction, low energy loss and high power generation efficiency.

[0006] The technical solutions adopted by the present invention to solve the technical problems are as follows:

[0007] An in-situ geothermal power generation system, comprising:

[0008] A heat pipe is vertically buried underground, with its upper end extending to the ground surface or a body of water and its lower end located above a geothermal source; a circulation cavity is formed within the heat pipe, and a circulating medium is disposed within the circulation cavity, the circulating medium being convertible between a liquid working medium and a vapor working medium;

[0009] A thermoelectric temperature difference power generation device and a magnetic levitation power generation device, wherein the thermoelectric temperature difference power generation device is located on the outside of the tube wall at the lower end of the heat pipe, and the magnetic levitation power generation device is located on the inside of the tube wall in the middle of the heat pipe. The thermoelectric temperature difference power generation device and the magnetic levitation power generation device output electrical energy to the outside through the power output port.

[0010] Compared with existing technologies, this technical solution has the following advantages: the system is directly installed at the geothermal source, with the heat pipe buried deep underground, and the lower end of the heat pipe located at the geothermal source. On the one hand, the thermoelectric temperature difference power generation device located at the lower end of the heat pipe can directly convert geothermal energy into electrical energy. On the other hand, the circulating working fluid can be converted between liquid and vapor working fluids. After the circulating working fluid absorbs heat from the liquid working fluid and converts to vapor working fluid, the upward vapor working fluid drives the magnetic levitation power generation device located in the middle of the heat pipe, converting the geothermal energy into mechanical energy and further into electrical energy. By directly utilizing geothermal energy to generate electricity, this system has the advantages of low energy loss and high power generation efficiency.

[0011] Furthermore, the thermoelectric temperature difference power generation device includes a plurality of thermoelectric power generation devices, and the plurality of thermoelectric power generation devices are circumferentially arranged on the outer side of the pipe wall of the heat pipe;

[0012] The thermoelectric generator is provided with a hot end and a cold end on two opposite sides, respectively. The thermoelectric generator is attached to the outer side of the heat pipe wall, the cold end of the thermoelectric generator is located on the side close to the heat pipe, and the hot end of the thermoelectric generator is located on the side away from the heat pipe.

[0013] The beneficial effect of adopting the above scheme is: by circumferentially arranging multiple thermoelectric power generation devices on the outside of the heat pipe wall to form a thermoelectric temperature difference power generation device, the contact area between the thermoelectric power generation devices and the geothermal source is maximized, which can improve the utilization rate of geothermal energy.

[0014] Furthermore, a heat sink is provided on the inner side of the heat pipe wall, and the heat sink is located at a position corresponding to the cold end of the thermoelectric power generation device. The heat sink is used to transfer heat from the cold end of the thermoelectric power generation device to the circulation cavity.

[0015] The beneficial effect of adopting the above solution is that it not only helps to form a reasonable temperature difference between the cold end and the hot end of the thermoelectric power generation device, but also ensures that the liquid working medium is quickly evaporated and vaporized to form a vapor working medium that moves upward.

[0016] Furthermore, a plurality of the thermoelectric power generation devices form a series structure, a parallel structure or a series-parallel structure;

[0017] When a plurality of the thermoelectric power generation devices form a series structure, in two adjacent thermoelectric power generation devices, the positive electrode connection end of the preceding thermoelectric power generation device is connected to the negative electrode connection end of the following thermoelectric power generation device, the negative electrode connection end of the first thermoelectric power generation device forms the negative electrode of the thermoelectric thermoelectric power generation device, and the positive electrode connection end of the last thermoelectric power generation device forms the positive electrode of the thermoelectric thermoelectric power generation device;

[0018] When a plurality of the thermoelectric power generation devices form a parallel structure, the positive electrode connection ends of the plurality of thermoelectric power generation devices are connected to form the positive electrode of the thermoelectric thermoelectric power generation device, and the negative electrode connection ends of the plurality of thermoelectric power generation devices are connected to form the negative electrode of the thermoelectric thermoelectric power generation device;

[0019] When a series-parallel structure is formed between multiple thermoelectric power generation devices, several thermoelectric power generation devices are connected in series to form a series thermoelectric power generation module. In the series thermoelectric power generation module, among two adjacent thermoelectric power generation devices, the positive connection end of the previous thermoelectric power generation device is connected to the negative connection end of the next thermoelectric power generation device, the negative connection end of the first thermoelectric power generation device forms the negative connection end of the series thermoelectric power generation module, and the positive connection end of the last thermoelectric power generation device forms the positive connection end of the series thermoelectric power generation module; the positive connection ends of multiple series thermoelectric power generation modules are connected to form the positive electrode of the thermoelectric temperature difference power generation device, and the negative connection ends of multiple series thermoelectric power generation modules are connected to form the negative electrode of the thermoelectric temperature difference power generation device.

[0020] The beneficial effect of adopting the above solution is: depending on the actual situation, the multiple thermoelectric power generation devices in the thermoelectric temperature difference power generation device are formed into a series structure, a parallel structure or a series-parallel structure to better output electrical energy.

[0021] Furthermore, the magnetic levitation power generation device includes a magnetic levitation radial bearing, a generator stator coil, an impeller outer permanent magnet, an impeller blade, and a magnetic levitation axial bearing; the impeller outer permanent magnet is arranged inside the generator stator coil through the magnetic levitation radial bearing and the magnetic levitation axial bearing;

[0022] The liquid working medium at the lower end of the heat pipe absorbs heat and vaporizes to form a vapor working medium that moves upward. The vapor working medium drives the impeller blades, and the impeller blades drive the permanent magnet outside the impeller to rotate in the stator coil of the generator. The stator coil of the generator cuts the magnetic induction lines of the permanent magnet outside the impeller to generate current.

[0023] The beneficial effects of adopting the above scheme are: on the one hand, it eliminates the friction inside the magnetic levitation power generation device, thereby improving the power generation efficiency; on the other hand, it uses the generator stator coil to cut the magnetic induction lines of the permanent magnet outside the impeller to generate current, thereby converting mechanical energy into electrical energy.

[0024] Furthermore, a plurality of heat transfer fins are provided in the heat pipe, the heat transfer fins are provided at the upper section of the heat pipe, and the plurality of heat transfer fins are arranged circumferentially, and the heat transfer fins are used to condense the circulating working medium from a vapor working medium to a liquid working medium.

[0025] The beneficial effect of adopting the above solution is that after the vapor working medium passes through the impeller blades, the heat of the vapor working medium is absorbed by the heat transfer fins, thereby helping to condense the vapor working medium into liquid working medium.

[0026] Furthermore, the heat transfer sheet is a T-shaped heat transfer component;

[0027] The T-shaped heat transfer assembly includes a first heat transfer fin and a second heat transfer fin, one end of the first heat transfer fin is arranged in the middle of the second heat transfer fin, and the other end of the first heat transfer fin is arranged on the inner side of the heat pipe wall;

[0028] A gap is provided between the second heat transfer plates of two adjacent T-shaped heat transfer components.

[0029] The beneficial effect of adopting the above solution is that the heat transfer plate is set as a T-shaped heat transfer component, which can improve the condensation efficiency on the one hand and ensure that the liquid working medium can smoothly fall into the lower end of the heat pipe on the other hand.

[0030] Furthermore, an epitaxial cooling pipe is provided at the upper end of the heat pipe, and the epitaxial cooling pipe extends to the ground surface or above the water body.

[0031] The beneficial effect of adopting the above solution is that by arranging an extension cooling pipe extending to the ground surface or above the water body above the heat pipe, it can better ensure that the vapor working medium can be more fully condensed into liquid working medium.

[0032] Furthermore, the epitaxial cooling tube is provided with a plurality of external heat dissipation components, which are circumferentially arranged on the outside of the tube wall of the epitaxial cooling tube, and the external heat dissipation components extend outward in a direction away from the center of the epitaxial cooling tube.

[0033] The beneficial effect of adopting the above solution is that an external heat dissipation component is provided on the outside of the tube wall of the epitaxial cooling tube, which can further ensure the condensation effect.

[0034] Furthermore, a head guard is provided at the lower end of the heat pipe.

[0035] The beneficial effect of adopting the above solution is that the provision of the head protector can protect the equipment from being damaged when the lower pipe is installed. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is an overall schematic diagram of an in-situ geothermal power generation system of the present invention.

[0037] Figure 2 This is a flow diagram of circulating working fluid in an in-situ geothermal power generation system of the present invention.

[0038] Figure 3 It is a structural schematic diagram of a high-temperature power generation section in an in-situ geothermal power generation system of the present invention.

[0039] Figure 4 It is a schematic diagram of a series structure circuit of thermoelectric power generation devices in an in-situ geothermal power generation system of the present invention.

[0040] Figure 5 It is a schematic diagram of a parallel structure circuit of thermoelectric power generation devices in an in-situ geothermal power generation system of the present invention.

[0041] Figure 6 It is a schematic diagram of a series-parallel structure circuit of thermoelectric power generation devices in an in-situ geothermal power generation system of the present invention.

[0042] Figure 7 It is a structural schematic diagram of a medium-temperature insulation section in an in-situ geothermal power generation system of the present invention.

[0043] Figure 8 It is a structural schematic diagram of a normal temperature cooling section in an in-situ geothermal power generation system of the present invention.

[0044] Figure 9 It is a structural schematic diagram of the air condensation section in an in-situ geothermal power generation system of the present invention.

[0045] In the figure, the components represented by each reference numeral are as follows:

[0046] Heat pipe 1, thermoelectric temperature difference power generation device 2, magnetic levitation power generation device 3, heat transfer plate 4, epitaxial cooling tube 5, external heat dissipation component 6, head guard 7;

[0047] High-temperature rock layer 101, medium-temperature rock layer 102, normal-temperature soil layer 103, and water layer 104;

[0048] Thermoelectric power generation device 201, heat sink 202;

[0049] Magnetic suspension radial bearing 301 , generator stator coil 302 , impeller outer permanent magnet 303 , impeller blade 304 , magnetic suspension axial bearing 305 . DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solutions and advantages of the present invention more clear and distinct, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0051] In the description of the present invention, it should be understood that the terms "center," "upper," "lower," "front," "back," "left," and "right" and the like, indicating positions or relationships, are based on the positions or relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0052] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" 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 an indirect connection through an intermediate medium, or it can be a communication between the two components. When a component is referred to as being "fixed to" or "set on" another element, it can be directly on the other component or there can also be a central component. When a component is considered to be "connected" to another element, it can be directly connected to the other element or there can be a central element at the same time. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] Compared to other energy sources, geothermal energy offers promising application prospects due to its abundant reserves, clean, environmentally friendly, and renewable nature. Geothermal power generation is a key area of clean energy development. However, existing technologies for utilizing geothermal energy are limited by the difficulty of deep energy extraction, high energy losses, and low power generation efficiency. Consequently, geothermal power generation still accounts for a small proportion of total power generation. Addressing these issues will overcome the bottlenecks in geothermal energy application and enable its fuller utilization.

[0054] To address this problem, the present invention provides an in-situ geothermal power generation system, comprising a heat pipe, a thermoelectric thermoelectric power generation device, and a magnetic levitation power generation device. The heat pipe is formed by a pipe wall, and the heat pipe forms the circulation cavity through the pipe wall; the lower end of the heat pipe is provided with a head guard. The system is directly installed at the geothermal source, and the heat pipe is buried underground so that the lower end of the heat pipe is located in the high-temperature rock layer underground; preferably, the heat pipe is buried vertically underground to ensure that the liquid working medium can be affected by gravity and fall along the pipe wall to the lower end of the heat pipe; the thermoelectric thermoelectric power generation device is arranged on the outside of the pipe wall of the heat pipe, and the magnetic levitation power generation device is arranged on the inside of the pipe wall of the heat pipe. The greatest innovation of the present invention is to directly utilize heat pipes, thermoelectric thermoelectric power generation devices, and magnetic levitation power generation devices for in-situ power generation. By installing the system at a geothermal source underground or on the seabed, geothermal energy can be directly converted into electrical energy and output to the ground, without the need to extract the energy in various forms as in the prior art, effectively avoiding energy loss.

[0055] The upper end of the heat pipe extends to the surface or water body, and the lower end of the heat pipe is located in the high-temperature rock layer underground; a circulation cavity is formed in the heat pipe, and a circulating working medium is arranged in the circulation cavity. The circulating working medium can be converted between liquid working medium and vapor working medium: when the circulating working medium absorbs heat, it will change from liquid working medium to vapor working medium; when the circulating working medium dissipates heat, it will change from vapor working medium to liquid working medium.

[0056] The present invention includes two devices for generating electricity: a thermoelectric temperature difference power generation device and a magnetic levitation power generation device. The thermoelectric temperature difference power generation device is located at the lower end of the heat pipe, and the magnetic levitation power generation device is located in the middle of the heat pipe. The thermoelectric temperature difference power generation device and the magnetic levitation power generation device output electrical energy to the outside through the power output port. On the one hand, the temperature at the lower end of the heat pipe is relatively high, and the thermoelectric temperature difference power generation device can directly convert geothermal energy into electrical energy; on the other hand, the liquid working fluid at the lower end of the heat pipe is heated and vaporized, and then converted into a gaseous working fluid that moves upward, driving the magnetic levitation power generation device to generate electricity, converting geothermal energy into mechanical energy and then into electrical energy. Through the above technical solution, the characteristics of efficient heat transfer of heat pipes and high-speed flow of gas working fluids are utilized to combine thermoelectric power generation and magnetic levitation power generation, which has the advantages of low energy loss and high power generation efficiency.

[0057] The heat pipe is a tubular structure, with all four sides of its lower end simultaneously exposed to high-temperature rock layers. To improve the utilization rate of geothermal energy, the thermoelectric power generation device includes multiple thermoelectric generating devices, which are arranged circumferentially on the outside of the heat pipe wall. Thermoelectric generating devices utilize temperature differences to generate electricity. Therefore, the thermoelectric generating devices are provided with a hot end and a cold end on opposite sides of the heat pipe wall. The thermoelectric generator is attached to the outside of the heat pipe wall, with the cold end of the thermoelectric generating device located on the side closest to the heat pipe and the hot end of the thermoelectric generating device located on the side away from the heat pipe. In this system, the thermoelectric generating devices are attached to the outside of the heat pipe wall, so the hot end of the thermoelectric generating device is located on the side away from the heat pipe; conversely, the cold end of the thermoelectric generating device is located on the side closer to the heat pipe. Heat from the geothermal source is transferred through the thermoelectric generating devices and the pipe wall to the interior of the heat pipe, where it is absorbed by the circulating working fluid within the circulation cavity. A thermoelectric temperature difference power generation device is composed of multiple thermoelectric power generation devices, and multiple thermoelectric power generation devices are arranged circumferentially on the outside of the heat pipe wall, so that each place around the heat pipe that contacts the high-temperature rock layer has a corresponding thermoelectric power generation device, thereby increasing the coverage area of the thermoelectric power generation device and thus improving the utilization rate of geothermal energy.

[0058] Thermoelectric devices generate electricity through temperature differences. Therefore, maintaining a reasonable temperature difference between the cold and hot ends of the thermoelectric device is crucial for power generation efficiency. To this end, the present invention inventively provides a heat sink at the cold end of the thermoelectric device. The heat sink is used to transfer heat from the cold end of the thermoelectric device to the circulation cavity. The heat sink is installed at the cold end of the thermoelectric device. During the process of heat transfer from the thermoelectric device through the heat pipe to the circulation cavity, the thermoelectric device is closest to the geothermal source, and the temperature of the hot end of the thermoelectric device is higher. Heat energy is transferred from the hot end of the thermoelectric device through the pipe wall and then transferred to the circulation cavity through the heat sink, thereby reducing the temperature. The heat sink installed at the cold end of the thermoelectric device can quickly dissipate heat from the cold end, reducing the temperature of the cold end and creating a reasonable temperature difference between the cold and hot ends of the thermoelectric device, thereby improving the efficiency of the thermoelectric device. It also improves thermal conductivity, ensuring that the liquid working medium at the lower end of the heat pipe quickly evaporates to form a vapor working medium that moves upward.

[0059] In order to better output electrical energy, multiple thermoelectric power generation devices can be connected in series, in parallel, or in series-parallel, depending on the actual situation. When multiple thermoelectric power generation devices are connected in series, in two adjacent thermoelectric power generation devices, the positive connection end of the previous thermoelectric power generation device is connected to the negative connection end of the next thermoelectric power generation device, the negative connection end of the first thermoelectric power generation device forms the negative electrode of the thermoelectric thermoelectric power generation device, and the positive connection end of the last thermoelectric power generation device forms the positive electrode of the thermoelectric thermoelectric power generation device; when multiple thermoelectric power generation devices are connected in parallel, the positive connection ends of multiple thermoelectric power generation devices are connected to form the positive electrode of the thermoelectric thermoelectric power generation device, and the negative connection ends of multiple thermoelectric power generation devices are connected to form the negative electrode of the thermoelectric thermoelectric power generation device; when multiple thermoelectric power generation devices are connected in parallel, the positive connection ends of multiple thermoelectric power generation devices are connected to form the positive electrode of the thermoelectric thermoelectric power generation device, and the negative connection ends of multiple thermoelectric power generation devices are connected to form the negative electrode of the thermoelectric thermoelectric power generation device; When a series-parallel structure is formed, several thermoelectric power generation devices are connected in series to form a series thermoelectric power generation module. In the series thermoelectric power generation module, the positive connection end of the previous thermoelectric power generation device of two adjacent thermoelectric power generation devices is connected to the negative connection end of the next thermoelectric power generation device. The negative connection end of the first thermoelectric power generation device forms the negative connection end of the series thermoelectric power generation module, and the positive connection end of the last thermoelectric power generation device forms the positive connection end of the series thermoelectric power generation module; the positive connection ends of multiple series thermoelectric power generation modules are connected to form the positive electrode of the thermoelectric temperature difference power generation device, and the negative connection ends of multiple series thermoelectric power generation modules are connected to form the negative electrode of the thermoelectric temperature difference power generation device.

[0060] The magnetic levitation power generation device of the present invention includes a magnetic levitation radial bearing, a generator stator coil, an impeller outer permanent magnet, impeller blades, and a magnetic levitation axial bearing. The impeller outer permanent magnet is disposed within the generator stator coil via the magnetic levitation radial bearing and the magnetic levitation axial bearing. A liquid working medium at the lower end of the heat pipe absorbs heat and vaporizes to form an upward-moving vapor. The vapor drives the impeller blades, which in turn drive the impeller outer permanent magnet to rotate within the generator stator coil. The generator stator coil cuts the magnetic flux lines of the impeller outer permanent magnet to generate current. By placing the impeller outer permanent magnet within the generator stator coil via the magnetic levitation radial bearing and the magnetic levitation axial bearing, friction within the magnetic levitation power generation device is eliminated, improving power generation efficiency. Furthermore, the vapor drives the impeller blades, which in turn drive the impeller outer permanent magnet to rotate within the generator stator coil. The generator stator coil cuts the magnetic flux lines of the impeller outer permanent magnet to generate current, thereby converting mechanical energy into electrical energy.

[0061] In order to better enable the circulating working fluid to change from a vaporous working fluid to a liquid working fluid, a plurality of heat transfer fins are provided within the heat pipe, and the plurality of heat transfer fins are arranged circumferentially; specifically, the heat transfer fins are provided at the upper section of the heat pipe. After the vaporous working fluid drives the magnetic levitation power generation device to generate electricity, its temperature remains relatively high and it is still in an upward motion state. The magnetic levitation power generation device is located in the middle of the heat pipe, and a plurality of heat transfer fins are provided at the upper section of the heat pipe. The heat transfer fins fully absorb the heat of the vaporous working fluid, and after releasing heat, the vaporous working fluid condenses, changes phase to a liquid working fluid, and re-enters the lower end of the heat pipe, repeating the cycle.

[0062] Specifically, the heat transfer plate is a T-shaped heat transfer assembly; the T-shaped heat transfer assembly includes a first heat transfer plate and a second heat transfer plate, one end of the first heat transfer plate is arranged in the middle of the second heat transfer plate, and the other end of the first heat transfer plate is arranged on the inner side of the tube wall of the heat pipe; there is a gap between the second heat transfer plates of two adjacent T-shaped heat transfer assemblies. Setting the heat transfer plate as a T-shaped heat transfer assembly can, on the one hand, increase the contact area between the vapor working medium and the heat transfer plate, thereby improving the condensation efficiency; on the other hand, the vapor working medium cannot directly reach the inner side of the tube wall of the heat pipe, but is blocked by the second heat transfer plate, while the liquid working medium falls between the second heat transfer plate and the inner side of the tube wall of the heat pipe, thereby separating the vapor working medium channel and the liquid working medium channel, ensuring that the liquid working medium can smoothly fall into the lower end of the heat pipe.

[0063] In order to fully condense the vaporous working medium and ensure the normal operation of the system, an epitaxial cooling pipe is further provided above the upper end of the heat pipe, and the epitaxial cooling pipe extends to the ground surface or above the water body. In addition, a plurality of external heat dissipation components are provided on the epitaxial cooling pipe, and the plurality of external heat dissipation components are circumferentially arranged on the outside of the tube wall of the epitaxial cooling pipe, and the external heat dissipation components extend outward in a direction away from the center of the epitaxial cooling pipe. By providing an epitaxial cooling pipe extending to the ground surface or above the water body above the heat pipe, it can be better ensured that the vaporous working medium can be more fully condensed into a liquid working medium; and by providing an external heat dissipation component on the outside of the tube wall of the epitaxial cooling pipe, the condensation effect can be further guaranteed.

[0064] The basic principle and composition structure of the in-situ geothermal power generation system of the present invention are described in detail below with reference to the accompanying drawings.

[0065] like Figure 1As shown, the geological layer structure involved in the present invention includes, from bottom to top, a high-temperature rock layer 101, a medium-temperature rock layer 102, and a normal-temperature soil layer 103; in some application scenarios, it also includes a water layer 104. The heat pipe 1 is buried underground, wherein the lower end of the heat pipe 1 is located near the geothermal source, that is, in the high-temperature rock layer 101, and the upper end of the heat pipe 1 extends to the surface or the water body. The thermoelectric temperature difference power generation device 2 for power generation is located on the outside of the pipe wall at the lower end of the heat pipe 1, and the magnetic levitation power generation device 3 is arranged on the inside of the pipe wall in the middle of the heat pipe 1; in addition, from the perspective of the geological layer structure, the thermoelectric temperature difference power generation device 2 is located in the high-temperature rock layer 101, and the magnetic levitation power generation device 3 is located in the medium-temperature rock layer 102.

[0066] Based on the temperature, this system can be divided into at least three distinct operating sections: a high-temperature power generation section, a medium-temperature insulation section, and a normal-temperature cooling section. The high-temperature power generation section is located within the high-temperature rock layer 101, the medium-temperature insulation section is located within the medium-temperature rock layer 102, and the normal-temperature cooling section is located above the normal-temperature soil layer 103. Specifically, the high-temperature power generation section operates at temperatures above 200°C, the medium-temperature insulation section operates between 50°C and 200°C, and the normal-temperature cooling section operates below 50°C.

[0067] like Figure 1 and Figure 2 As shown, the liquid working medium is heated at the lower end of the heat pipe 1 and vaporized into a vapor working medium, which then moves upward along the circulation cavity. After the vapor working medium drives the magnetic levitation power generation device 3 to operate, it continues to move upward and reaches the normal temperature cooling section. At this time, the ambient temperature is relatively low, and the high-temperature vapor working medium is cooled near the inner wall of the heat pipe 1, releasing heat and condensing into a liquid working medium. Thereafter, the liquid working medium is acted upon by gravity and falls along the inner wall of the heat pipe 1, re-enters the lower end of the heat pipe 1, and undergoes the vaporization-condensation cycle again.

[0068] like Figure 2 As shown, a head guard 7 is provided at the lower end of the heat pipe 1. The head guard 7 is a hemispherical metal structure so as to protect the equipment from being damaged when the pipe is installed on site. A temperature sensor can be installed inside the head guard for temperature detection.

[0069] like Figure 3As shown, in the high-temperature power generation section, the system's structure, from the outside to the inside, includes a protective layer, thermoelectric generator 201, heat pipe 1, and heat sink 202. The core component of the high-temperature power generation section is the thermoelectric generator 201, which is attached to the outside of the heat pipe 1. To prevent direct contact between the thermoelectric generator 201 and the geothermal source, a protective layer is placed between the protective layer and the heat pipe 1. By utilizing the temperature difference between the inside and outside of the heat pipe 1, the thermoelectric generator 201 directly converts geothermal energy into electricity. This external protective layer protects the thermoelectric generator 201 during pipe installation and prevents direct contact between the thermoelectric generator 201 and related wiring from the high-temperature rock layer 101. Specifically, the protective layer is made of a material with excellent thermal conductivity, ensuring that heat energy from the high-temperature rock layer 101 is reliably transferred to the hot end of the thermoelectric generator 201. Specifically, the protective layer can be made of copper. It should be noted that, when implementing the technical solution of the present invention, different materials can be selected for the protective layer based on practical circumstances, as long as the material exhibits properties such as high strength and good thermal conductivity. The above embodiments are merely illustrative and do not define or restrict the material of the protective layer. A heat sink 202 is provided at the cold end of the thermoelectric generator 201 to increase the heat dissipation area and ensure rapid evaporation of the liquid working medium, transforming it into a vapor phase.

[0070] According to different circuit connection modes of the thermoelectric temperature difference power generation device 2 , there are three circuit connection modes: a series structure, a parallel structure, or a series-parallel structure.

[0071] like Figure 4 As shown, the series structure is composed of several thermoelectric generating devices 201 connected in series via a circuit, with the positive and negative terminals of two adjacent thermoelectric generating devices 201 short-circuited. For ease of understanding, the thermoelectric generating devices 201 are numbered 1, 2, 3, ..., n. The positive terminal of thermoelectric generating device 201 No. 1 serves as the positive terminal of thermoelectric thermoelectric power generation device 2, and its negative terminal is connected to the positive terminal of thermoelectric generating device 2 No. 2. The negative terminal of thermoelectric generating device 201 No. n serves as the negative terminal of thermoelectric thermoelectric power generation device 2, and its positive terminal is connected to the negative terminal of thermoelectric generating device 2 No. n-1. For other thermoelectric generating devices 201, the positive and negative terminals of two adjacent thermoelectric generating devices 201 are short-circuited.

[0072] like Figure 5 As shown, the parallel structure is composed of several thermoelectric power generation devices 201 through a parallel circuit. The positive connection ends of all thermoelectric power generation devices 201 are short-circuited to each other, and the connected terminals serve as the positive pole of the entire thermoelectric temperature difference power generation device 2; the negative connection ends of all thermoelectric power generation devices 201 are short-circuited to each other, and the connected terminals serve as the negative pole of the entire thermoelectric temperature difference power generation device 2.

[0073] like Figure 6 As shown, the series-parallel structure is constructed by connecting multiple thermoelectric generating devices 201 in series and parallel. First, multiple thermoelectric generating devices 201 are connected in series to form a series thermoelectric generating module. Within the series thermoelectric generating module, the positive terminal of the preceding thermoelectric generating device 201 is connected to the negative terminal of the following thermoelectric generating device 201. Then, the positive terminals of the multiple series thermoelectric generating modules are short-circuited to form the positive terminal of the thermoelectric thermoelectric generating device 2, and the negative terminals of the multiple series thermoelectric generating modules are short-circuited to form the negative terminal of the thermoelectric thermoelectric generating device 2.

[0074] like Figure 1 and Figure 7 As shown, in the medium-temperature insulation section, the gaseous working medium moving from the bottom to the top in the high-temperature power generation section is used to drive the magnetic levitation power generation device 3 to generate electricity. The core of this part is the magnetic levitation power generation device 3, which is composed of a magnetic levitation radial bearing 301, a generator stator coil 302, an impeller outer permanent magnet 303, an impeller blade 304 and a magnetic levitation axial bearing 305. The gaseous working medium is used to drive the impeller blade 304, that is, to realize the conversion of thermal energy into mechanical energy. The impeller blade 304 drives the impeller outer permanent magnet 303 in the generator stator coil 302, and the generator stator coil 302 cuts the magnetic lines of force, thereby generating current. Specifically, a thermal insulation layer is provided on the outer side of the pipe wall of the heat pipe 1 in the medium-temperature insulation section. The moisture-retaining insulation layer prevents the heat pipe from exchanging heat with the outside world. More specifically, the material of the thermal insulation layer is not limited, and it only needs to play the role of isolating heat transfer.

[0075] The magnetically suspended radial bearing 301 and the magnetically suspended axial bearing 305 serve to reduce the bearing rotational friction of the rotor, thereby ensuring that the impeller blades 304 can also be driven to rotate using a vaporous working medium with lower mechanical energy. Specifically, the rotor of the magnetically suspended power generation device 3 rotates vertically in the heat pipe 1. During the operation of the magnetically suspended power generation device 3, the rotor is suspended in the middle of the heat pipe 1 and rotates at high speed. On the one hand, due to the effect of gravity, an upward force needs to be applied to the rotor to maintain force balance in the vertical direction. In the present invention, the magnetic force of the magnetically suspended axial bearing 305 is used to offset the weight of the rotor, preventing the rotor from falling without direct contact. On the other hand, the rotor must remain in the center of the heat pipe 1 during rotation and cannot deviate. In the present invention, the magnetic force of the magnetically suspended radial bearing 301 is used to ensure that the rotor is in the center of the heat pipe 1 without direct contact.

[0076] like Figure 8As shown, the function of the normal temperature cooling section is to cool the vapor working medium passing through the magnetic levitation power generation device 3 into a liquid working medium. A circulation cavity is formed in the heat pipe 1. The center of the circulation cavity is a vapor working medium channel, and the vapor working medium moves upward in the vapor working medium channel; while the area between the periphery of the circulation cavity and the inner side of the pipe wall of the heat pipe 1 is a liquid working medium channel, and the liquid working medium moves downward in the liquid working medium channel.

[0077] Heat transfer fins 4 are installed on the inner wall of heat pipe 1. These fins are T-shaped components. The protruding fins 4 increase the heat exchange area, improving the cooling effect and ensuring sufficient condensation. Furthermore, the gaps between the fins allow a small amount of gas to pass through, increasing the heat exchange area while also reducing the impact of the vapor on the liquid near the inner wall of heat pipe 1, preventing the vapor and liquid from interfering with each other.

[0078] The normal temperature cooling section is located above the normal temperature soil layer 103 and may also pass through the water layer 104. However, after passing through the normal temperature soil layer 103 and the water layer 104, the condensation effect may still be limited because the ambient temperature is not low enough.

[0079] like Figure 1 and Figure 2 As shown, preferably, in order to solve the above problems, an air condensation section is further provided at the upper end of the heat pipe 1, and the air condensation section is arranged above the ground surface or water body. On the basis of the ground surface, water body, etc., heat exchange is carried out through air with lower temperature to achieve further cooling, so as to ensure sufficient condensation of the vaporous working medium.

[0080] like Figure 1 、 Figure 2 and Figure 9 As shown, the air condensation section is formed by extending an extension cooling tube 5 from the heat pipe 1, wherein the extension cooling tube 5 and the heat pipe 1 are integrally formed. Multiple external heat dissipation components 6 are provided on the outside of the air condensation section. These components are arranged circumferentially and extend outward away from the center of the extension cooling tube 5 to increase the heat exchange area with the surrounding air. Heat transfer fins 4 are still provided inside the air condensation section, but because the temperature of the vaporous working medium in this section is lower than that in the normal temperature cooling section, the gaps between the heat transfer fins 4 are appropriately increased.

[0081] In summary, the present invention provides an in-situ geothermal power generation system, comprising a heat pipe, a thermoelectric temperature difference power generation device and a magnetic levitation power generation device; the heat pipe is buried underground, the upper end of the heat pipe extends to the surface or water body, and the lower end of the heat pipe is located on the geothermal source; a circulation cavity is formed in the heat pipe, and a circulating working fluid is provided in the circulation cavity, and the circulating working fluid can be converted between liquid working fluid and vapor working fluid; the thermoelectric temperature difference power generation device is located at the lower end of the heat pipe, and the magnetic levitation power generation device is located in the middle of the heat pipe, and the thermoelectric temperature difference power generation device and the magnetic levitation power generation device output electrical energy to the outside through the power output port. Compared with existing technologies, this technical solution has the following advantages: the system is directly installed at the geothermal source, with the heat pipe buried deep underground, with the lower end of the heat pipe located at the geothermal source. On the one hand, the thermoelectric temperature difference power generation device located at the lower end of the heat pipe can directly convert geothermal energy into electricity. On the other hand, after the liquid working fluid absorbs heat and converts into vapor, the upward-flowing vapor drives the magnetic levitation power generation device located in the middle of the heat pipe, converting the geothermal energy into mechanical energy and then further into electricity. By directly utilizing geothermal energy to generate electricity, this system has the advantages of low energy loss and high power generation efficiency.

[0082] It should be understood that the application of the present invention is not limited to the above examples. For those skilled in the art, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. An in-situ geothermal power generation system, characterized in that: include: A heat pipe (1), wherein the heat pipe (1) is vertically buried underground, the upper end of the heat pipe (1) extends to the ground surface or a water body, and the lower end of the heat pipe (1) is located on a geothermal source; a circulation cavity is formed in the heat pipe (1), a circulating working medium is provided in the circulation cavity, and the circulating working medium can be converted between a liquid working medium and a vapor working medium; A thermoelectric temperature difference power generation device (2) and a magnetic levitation power generation device (3), wherein the thermoelectric temperature difference power generation device (2) is located on the outside of the pipe wall at the lower end of the heat pipe (1), and the magnetic levitation power generation device (3) is located on the inside of the pipe wall in the middle of the heat pipe (1), and the thermoelectric temperature difference power generation device (2) and the magnetic levitation power generation device (3) output electric energy to the outside through an electric energy output port; The thermoelectric temperature difference power generation device (2) comprises a plurality of thermoelectric power generation devices (201), and the plurality of thermoelectric power generation devices (201) are arranged circumferentially on the outside of the wall of the heat pipe (1); The thermoelectric power generation device (201) is provided with a hot end and a cold end on two opposite sides, respectively. The thermoelectric power generation device is attached to the outer side of the wall of the heat pipe (1), the cold end of the thermoelectric power generation device (201) is located on a side close to the heat pipe (1), and the hot end of the thermoelectric power generation device (201) is located on a side away from the heat pipe (1); A heat sink (202) is provided on the inner side of the wall of the heat pipe (1), and the heat sink (202) is located at a position corresponding to the cold end of the thermoelectric power generation device (201). The heat sink (202) is used to transfer heat from the cold end of the thermoelectric power generation device (201) to the circulation cavity, thereby reducing the temperature of the cold end and forming a temperature difference between the cold end and the hot end of the thermoelectric power generation device; A plurality of heat transfer fins (4) are provided in the heat pipe (1), the heat transfer fins (4) are provided at the upper section of the heat pipe (1), the plurality of heat transfer fins (4) are arranged along the circumferential direction, and the heat transfer fins (4) are used to condense the circulating working medium from a vapor working medium into a liquid working medium; The heat transfer plate (4) is a T-shaped heat transfer component; The T-shaped heat transfer assembly comprises a first heat transfer fin (4) and a second heat transfer fin (4), one end of the first heat transfer fin (4) being arranged at the middle of the second heat transfer fin (4), and the other end of the first heat transfer fin (4) being arranged on the inner side of the wall of the heat pipe (1); A gap is provided between the second heat transfer plates (4) of two adjacent T-shaped heat transfer assemblies.

2. The in-situ geothermal power generation system according to claim 1, characterized in that: A plurality of the thermoelectric generating devices (201) form a series structure, a parallel structure, or a series-parallel structure; When a series structure is formed between a plurality of the thermoelectric power generation devices (201), in two adjacent thermoelectric power generation devices (201), the positive electrode connection end of the preceding thermoelectric power generation device (201) is connected to the negative electrode connection end of the following thermoelectric power generation device (201), the negative electrode connection end of the first thermoelectric power generation device (201) forms the negative electrode of the thermoelectric temperature difference power generation device (2), and the positive electrode connection end of the last thermoelectric power generation device (201) forms the positive electrode of the thermoelectric temperature difference power generation device (2); When a parallel structure is formed between the plurality of thermoelectric power generation devices (201), the positive electrode connection ends of the plurality of thermoelectric power generation devices (201) are connected to form the positive electrode of the thermoelectric temperature difference power generation device (2), and the negative electrode connection ends of the plurality of thermoelectric power generation devices (201) are connected to form the negative electrode of the thermoelectric temperature difference power generation device (2); When a series-parallel structure is formed between the plurality of thermoelectric power generation devices (201), the plurality of thermoelectric power generation devices (201) are connected in series to form a series thermoelectric power generation module. In the series thermoelectric power generation module, in two adjacent thermoelectric power generation devices (201), the positive electrode connection end of the preceding thermoelectric power generation device (201) is connected to the negative electrode connection end of the following thermoelectric power generation device (201), the negative electrode connection end of the first thermoelectric power generation device (201) forms the negative electrode connection end of the series thermoelectric power generation module, and the positive electrode connection end of the last thermoelectric power generation device (201) forms the positive electrode connection end of the series thermoelectric power generation module; the positive electrode connection ends of the plurality of series thermoelectric power generation modules are connected to form the positive electrode of the thermoelectric temperature difference power generation device (2), and the negative electrode connection ends of the plurality of series thermoelectric power generation modules are connected to form the negative electrode of the thermoelectric temperature difference power generation device (2).

3. The in-situ geothermal power generation system according to claim 1, characterized in that: The magnetic levitation power generation device (3) comprises a magnetic levitation radial bearing (301), a generator stator coil (302), an impeller outer permanent magnet (303), an impeller blade (304), and a magnetic levitation axial bearing (305); the impeller outer permanent magnet (303) is arranged inside the generator stator coil (302) via the magnetic levitation radial bearing (301) and the magnetic levitation axial bearing (305); The liquid working medium at the lower end of the heat pipe (1) absorbs heat and vaporizes to form a vapor working medium that moves upward. The vapor working medium drives the impeller blades (304). The impeller blades (304) drive the impeller external permanent magnet (303) to rotate in the generator stator coil (302). The generator stator coil (302) cuts the magnetic induction lines of the impeller external permanent magnet (303) to generate current.

4. The in-situ geothermal power generation system according to claim 1, characterized in that: An extension cooling pipe (5) is also provided at the upper end of the heat pipe (1), and the extension cooling pipe (5) extends to the ground surface or above the water body.

5. The in-situ geothermal power generation system according to claim 4, characterized in that: The epitaxial cooling tube (5) is provided with a plurality of external heat dissipation components (6), the plurality of external heat dissipation components (6) being circumferentially arranged on the outside of the tube wall of the epitaxial cooling tube (5), and the external heat dissipation components (6) extending outward in a direction away from the center of the epitaxial cooling tube (5).

6. The in-situ geothermal power generation system according to any one of claims 1 to 5, characterized in that: The lower end of the heat pipe (1) is provided with a head guard (7).

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