Downhole while-drilling active refrigeration temperature difference power generation device and downhole power generation system

Abstract

The application provides a downhole while-drilling active refrigeration temperature difference power generation device and a downhole power generation system, and relates to the field of energy sources.The downhole while-drilling active refrigeration temperature difference power generation device comprises a power transmission module, a refrigeration module, a thermal management module, a while-drilling instrument electric control module and a power generation module; the power transmission module is magnetically coupled with the refrigeration module, and is used for driving the refrigeration module to generate cold energy by taking downhole fluid as a motive energy source; the thermal management module transmits cold energy to the power generation module; the power generation module comprises at least one temperature difference power generation sheet, is connected in series with the while-drilling instrument electric control module, is used for generating power by using a temperature difference, and supplies power to the while-drilling instrument electric control module and while-drilling instruments carried by the while-drilling instrument electric control module. Through the application, the temperature difference power generation method can be used to stably generate power in a downhole environment, and the effect of providing stable electric energy for while-drilling instruments can be achieved.

Description

Technical Field

[0001] This application relates to the energy field, and in particular to a downhole active cooling thermoelectric generator and a downhole power generation system. Background Technology

[0002] During drilling operations, downhole power generation technology is needed to provide electricity to the drilling instruments. Currently, commonly used downhole power generation methods include turbine generators, lithium battery pack sub-junctions, and downhole cables. These methods have relatively sound operating principles and are widely used in field operations. However, based on an average formation gradient of 3℃ / 100m, when the downhole ambient temperature reaches 175℃ (approximately 6000m in drilling depth), the aforementioned and other commonly used downhole active cooling thermoelectric generators will experience unstable power supply, irregular malfunctions, or even breakdowns due to the high downhole environment. This can lead to power outages and cessation of operation of the drilling instruments, making it impossible to obtain the necessary critical downhole parameters, thus limiting drilling depth, increasing the accident rate, and significantly impacting construction progress and costs.

[0003] Therefore, there is an urgent need for a new type of downhole power generation technology that can overcome the effects of high-temperature downhole environments and provide a stable power supply for drilling instruments. Summary of the Invention

[0004] This application provides a downhole active cooling thermoelectric generator and a downhole power generation system to achieve stable power generation in the downhole environment using thermoelectric power generation, thereby providing stable power to the drilling instruments.

[0005] In a first aspect, embodiments of this application provide a downhole active cooling thermoelectric generator, comprising: a power transmission module, a cooling module, a thermal management module, a drilling instrument control module, and a power generation module;

[0006] The power transmission module and the refrigeration module are magnetically coupled to use the downhole fluid as a power source to drive the refrigeration module to generate cooling.

[0007] The thermal management module transfers cooling energy to the power generation module;

[0008] The power generation module includes at least one thermoelectric generator connected in series with the drilling instrument control module. It is used to generate electricity using the temperature difference and to supply power to the drilling instrument control module and the drilling instrument mounted on the drilling instrument control module.

[0009] In one possible implementation, the power transmission module includes: a turbine stator and a turbine rotor;

[0010] The turbine rotor has a built-in magnetic coupling device; the turbine stator is used to guide the inflowing liquid so that the liquid impacts the turbine rotor, driving the turbine rotor and the magnetic coupling device to rotate, and causing the magnetic coupling device to generate an alternating magnetic field.

[0011] In one possible implementation, the power transmission module includes: a turbine stator, a turbine rotor, a turbine drive shaft, a first gear, a second gear, and a magnetic coupler;

[0012] The first gear is mounted on the turbine drive shaft; the first gear meshes with the second gear; the second gear is rigidly connected to the magnetic coupler.

[0013] The turbine stator and turbine rotor in the turbine module are used to convert the kinetic energy of the incoming liquid into mechanical energy, driving the turbine drive shaft and the first gear to rotate. The second gear and the magnetic coupler rotate under the drive of the first gear, causing the magnetic coupler to generate an alternating magnetic field. In one possible implementation, the cooling module includes: a downhole drilling chiller and a cold head;

[0014] The downhole chiller is magnetically coupled to the power transmission module. Driven by the power transmission module, it generates cooling capacity, which is then transferred by the chiller head.

[0015] In one possible implementation, the downhole refrigeration unit uses a closed pneumatic refrigeration unit for regenerative refrigeration, consisting of a magnetically driven compressor and an expansion mechanism. In the chamber at the cold head, the expansion effect is greater than the compression effect, absorbing heat to form a low-temperature zone for refrigeration.

[0016] In one possible implementation, the thermal management module includes: heat-conducting cables and guide posts;

[0017] The cold side of the thermoelectric generator is close to the heat conduction cable to obtain cold energy, while the hot side of the thermoelectric generator is in contact with the heat source through the guide post to obtain heat.

[0018] In one possible implementation, the heat-conducting cable is made of copper and multilayer graphene.

[0019] In one possible implementation, the guide post is made of copper.

[0020] And / or, the top of the guide post is an arc surface that is in close contact with the heat source surface.

[0021] In one possible implementation, the power generation module also includes a transformer chip for converting the electricity generated by the thermoelectric generator into a voltage available to the drilling instrument.

[0022] In one possible implementation, the thermal management module transfers cooling energy to the drilling instrument control module; the thermal management module includes: heat-conducting cables and guide posts;

[0023] The heat-conducting cable is close to the Drilling Instrument Control Module (DIM) to transfer cooling energy to the DIM module.

[0024] The cold side of the thermoelectric generator is close to the drilling instrument's electronic control module to obtain cooling, while the hot side of the thermoelectric generator is in contact with the heat source through the guide post to obtain heat.

[0025] In one possible implementation, the cooling module, thermal management module, drilling instrument control module, and power generation module are all housed within a sealed, pressure-bearing housing. In a second aspect, embodiments of this application provide a downhole power generation system, comprising: a drill collar and a downhole active cooling thermoelectric generator as described in the first aspect and / or various possible implementations of the first aspect.

[0026] The downhole active cooling thermoelectric generator and downhole power generation system provided in this application embodiment use downhole fluid as the kinetic energy source to drive the cooling module to generate cooling capacity. A thermal management module transfers the cooling capacity generated by the cooling module to the downhole instrument control module to cool it down. The cooled down downhole instrument control module serves as the cold source for the power generation module. The power generation module uses thermoelectric generators to supply power to the downhole instrument control module, achieving stable power generation in the downhole environment using thermoelectric power generation to provide stable power to the downhole instrument. Attached Figure Description

[0027] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0028] Figure 1 Schematic diagram of the downhole active cooling thermoelectric generator provided in this application Figure 1 ;

[0029] Figure 2 A schematic diagram of the first gear and the second gear in the downhole active cooling thermoelectric generator provided in this application;

[0030] Figure 3 Schematic diagram of the downhole active cooling thermoelectric generator provided in this application Figure 2 ;

[0031] Figure 4 Schematic diagram of the downhole active cooling thermoelectric generator provided in this application Figure 3 ;

[0032] Figure 5 Cross-sectional view of section AA of the downhole active cooling thermoelectric generator provided in this application;

[0033] Figure 6 Schematic diagram of the downhole active cooling thermoelectric generator provided in this application Figure 4 ;

[0034] Figure 7Schematic diagram of the downhole power generation system provided in this application Figure 1 ;

[0035] Figure 8 Schematic diagram of the downhole active cooling thermoelectric generator provided in this application Figure 5 ;

[0036] Figure 9 Schematic diagram of the downhole power generation system provided in this application Figure 2 ;

[0037] Figure 10 Schematic diagram of the downhole power generation system provided in this application Figure 3 .

[0038] Explanation of reference numerals in the attached figures:

[0039] 1. Power transmission module;

[0040] 11. Turbine stator;

[0041] 12. Turbine rotor;

[0042] 13. Turbine drive shaft;

[0043] 14. First gear;

[0044] 15. Second gear;

[0045] 16. Magnetic coupler;

[0046] 2. Refrigeration module;

[0047] 21. Drilling chiller;

[0048] 22. Cooling head;

[0049] 3. Thermal management module;

[0050] 31. Heat-conducting cable;

[0051] 32. Guide post;

[0052] 4. Drilling instrument electrical control module;

[0053] 41. Drilling instruments;

[0054] 42. Wire;

[0055] 5. Power generation module;

[0056] 51. Thermoelectric generator;

[0057] 52. Transformer chip;

[0058] 6. Pressure-bearing outer casing;

[0059] 7. Positioning ring;

[0060] 8. Drill collar;

[0061] 81. Cabin;

[0062] 82. Hatch cover.

[0063] The accompanying drawings have illustrated specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to specific embodiments. Detailed Implementation

[0064] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the specific technical solutions of this application will be further described in detail below with reference to the accompanying drawings of the embodiments of this application. The following embodiments are used to illustrate this application, but are not intended to limit the scope of this application.

[0065] In the description of the embodiments of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0066] In the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0067] Due to the complex formation conditions and harsh environmental factors such as high temperatures in deep and ultra-deep drilling operations, the implementation of commonly used downhole power generation technologies is greatly affected. For example, turbine generators and lithium battery packs often malfunction at temperatures above 175°C, leading to power outages and shutdowns of drilling instruments. This makes it impossible to obtain the key downhole parameters required during drilling operations, thereby limiting the drilling depth and seriously affecting the progress of exploration, development and utilization of natural resources such as deep oil and gas reservoirs.

[0068] After decades of development, downhole power generation technology for use with downhole drilling instruments has reached near maturity. Currently, common methods include turbine generators, lithium battery sub-junctions, and downhole cables, all of which have relatively sound operating principles and are widely used in field operations. However, using an average formation gradient of 3℃ / 100m as a standard, when the downhole ambient temperature reaches 175℃ (approximately 6000m in drilling depth), the aforementioned and unmentioned commonly used downhole active cooling thermoelectric generators will experience unstable power supply, irregular malfunctions, or even breakdowns due to the high downhole environment. This can lead to power outages and cessation of operation of the drilling instruments, resulting in reduced drilling accuracy, increased accident rates, and significant impacts on construction progress and costs. Therefore, a new downhole power generation technology that can overcome the effects of high downhole environments is urgently needed.

[0069] Thermoelectric power generation is a novel power generation method that directly converts heat energy into electrical energy using the Seebeck effect. The Seebeck effect, also known as the first thermoelectric effect, refers to the thermoelectric phenomenon caused by the temperature difference between two different conductors or semiconductors, resulting in a voltage difference between them. Generally, the direction of the thermoelectric potential is defined as: electrons flow from negative to positive at the hot end. Thermoelectric generators are integrated from these thermoelectric semiconductors and can withstand temperatures above 175°C. This overcomes the frequent failures and subsequent maintenance problems of traditional power generation methods in high-temperature and high-pressure environments, and solves the practical problem of not being able to power the circuitry of drilling instruments in deep and ultra-deep drilling operations.

[0070] This application uses a thermoelectric generator as the core device of the power generation module and incorporates a power transmission mechanism that utilizes the kinetic energy of the drilling fluid to drive a cooling module. This provides cooling to the drilling instrument and the cold side of the thermoelectric generator, creating a significant temperature difference between the hot and cold ends of the generator, thereby generating stable direct current for the drilling instrument. The invention is applicable to the field of drilling tools for oil and gas exploration and development, and potential applications include downhole power generation in coal mines.

[0071] This application provides a downhole active cooling thermoelectric generator, referring to... Figure 1 , Figure 2 as well as Figure 3 The downhole active cooling thermoelectric generator includes: a power transmission module 1, a cooling module 2, a thermal management module 3, a drilling instrument electrical control module 4, and a power generation module 5.

[0072] The power transmission module 1 is magnetically coupled to the cooling module 2, which uses the downhole fluid as the kinetic energy to drive the cooling module 2 to generate cooling capacity. The cooling module 2 is used for cooling, providing cooling capacity to the power generation module 5 and the drilling instrument module 4. The thermal management module 3 transfers cooling capacity to the power generation module 5. The power generation module 5 includes at least one thermoelectric generator 51, which is connected in series with the drilling instrument control module 4. It is used to generate electricity using temperature difference and to supply power to the drilling instrument control module 4 and the drilling instrument 41 mounted on the drilling instrument control module 4.

[0073] In one embodiment, the power transmission module 1 uses the downhole fluid as kinetic energy to drive the cooling module 2 to cool the downhole active cooling and power generation device, so that the downhole active cooling and power generation device is in a relatively low temperature environment, providing cooling for the downhole instrument circuit 41 and ensuring its normal operation in a high-temperature environment.

[0074] A thermoelectric generator is a commonly used thermoelectric semiconductor with a hot side and a cold side. When the hot side is at a high temperature and the cold side is at a low temperature, the Seebeck effect occurs. This means that due to the stronger thermal excitation at the high-temperature end, the concentration of holes and electrons is higher than at the low-temperature end, causing charge carriers to diffuse from the high-temperature end to the low-temperature end, thus creating a potential difference at the low-temperature open-circuit end. Combining multiple such cells can form a thermoelectric generator.

[0075] In one embodiment, the power generation module 5 is equipped with multiple thermoelectric generators. The cold side of the thermoelectric generators is provided with cooling by the refrigeration module 2, and the hot side of the thermoelectric generators is provided with heat by a heat source with a higher temperature, thereby forming a temperature difference to generate electricity.

[0076] The downhole active cooling thermoelectric generator provided in this application adopts an active cooling method. It is equipped with a cooling module, which uses the downhole fluid as the kinetic energy source. The cooling module is driven by the power transmission module to generate cooling capacity. The cooling capacity can be used to provide a large temperature difference for the thermoelectric generator module, providing a stable power supply for the downhole instrument and ensuring that the downhole instrument can work stably in the high-temperature and harsh downhole environment. Moreover, the thermoelectric semiconductor chip is small in size and only needs to be installed on the circuit of the downhole instrument, further saving downhole space.

[0077] In one implementation, reference is made to Figure 3 The power transmission module 1 includes a turbine stator 11 and a turbine rotor 12.

[0078] The turbine rotor 12 has a built-in magnetic coupling device, and the turbine stator 11 is used to guide the inflowing liquid so that the liquid impacts the turbine rotor 12, driving the turbine rotor 12 and the magnetic coupling device to rotate, so that the magnetic coupling device generates an alternating magnetic field.

[0079] In the downhole scenario of oil drilling and production, the downhole fluid first flows into the turbine stator 11. The turbine stator 11 is equipped with blades that have a certain fluid guiding effect, so that the fluid impacts the turbine rotor 12. Compared with the fluid directly impacting the turbine rotor 12, this method can give the fluid impacting the turbine rotor 12 greater kinetic energy, making the turbine rotor 12 rotate at high speed. At the same time, the magnetic coupler installed in the turbine rotor 12 generates an alternating magnetic field, which can be magnetically coupled with other magnetic fields.

[0080] The downhole active cooling thermoelectric generator provided in this application is equipped with a power transmission module that includes a turbine stator and a turbine rotor. It converts the kinetic energy of the downhole fluid into mechanical energy, and causes the magnetic coupling device built into the turbine rotor to generate an alternating magnetic field, which can provide kinetic energy to the subsequent modules through magnetic force.

[0081] In one implementation, reference is made to Figure 1 and Figure 4 The power transmission module 1 includes: a turbine stator 11, a turbine rotor 12, a turbine drive shaft 13, a first gear 14, a second gear 15, and a magnetic coupler 16. The first gear 14 is mounted on the turbine drive shaft 13 in the turbine module, and the first gear 14 meshes with the second gear 15. The second gear 15 is rigidly connected to the magnetic coupler 16. The turbine stator 11 and the turbine rotor 12 are used to convert the kinetic energy of the flowing liquid into mechanical energy, driving the turbine drive shaft 13 and the first gear 14 to rotate. The second gear 15 and the magnetic coupler 16 rotate under the drive of the first gear 14, causing the magnetic coupler 16 to generate an alternating magnetic field.

[0082] The turbine stator 11 serves to guide the inflowing liquid, namely drilling fluid, so that the drilling fluid impacts the turbine rotor 12 at a high flow rate, causing the turbine rotor 12 to rotate. The turbine rotor 12 drives the first gear 14 and the second gear 15 to rotate through the turbine drive shaft 13. The second gear 15 is rigidly connected to the magnetic coupler 16, and the rotation of the magnetic coupler 16 generates an alternating magnetic field.

[0083] The power transmission module in the downhole active cooling thermoelectric generator provided in this application embodiment can convert the kinetic energy of drilling fluid into mechanical energy, providing power for subsequent modules. It is equipped with a turbine stator to increase the impact force of drilling fluid on the turbine rotor, and a magnetic coupler to use a non-contact energy transfer method to reduce device wear and increase device life.

[0084] In one embodiment, the cooling module 2 includes a downhole drilling chiller 21 and a cold head 22. The downhole drilling chiller 21 is magnetically coupled to the power transmission module 1 and generates cooling capacity under the drive of the power transmission module 1. The generated cooling capacity is transferred by the cold head 22.

[0085] A refrigeration machine is a device that transfers heat from a cooled object at a lower temperature to the surrounding environment to obtain cooling capacity. Refrigeration machines can be classified into: compression refrigeration machines, absorption refrigeration machines, vapor jet refrigeration machines, and semiconductor refrigeration. A cold head is a part of a small refrigeration machine; its main function is to cool components by making thermal contact with the cooling material.

[0086] The downhole active cooling thermoelectric generator provided in this application embodiment features a magnetic coupler in the power transmission module that rotates under the drive of drilling fluid, generating an alternating magnetic field. The downhole cooling unit in the cooling module has a built-in internal magnetic field, and the alternating magnetic field magnetically couples with the cooling unit, allowing the downhole cooling unit to rotate synchronously with the magnetic coupler. This non-contact driving method effectively reduces component wear and extends component lifespan.

[0087] The downhole refrigeration unit 21 uses a closed pneumatic refrigeration unit for regenerative refrigeration. It consists of a magnetically driven compressor and an expansion mechanism. In the chamber at the cold head 22, the expansion effect is greater than the compression effect, absorbing heat to form a low-temperature zone for refrigeration.

[0088] The downhole refrigeration unit 21 is filled with gas. The compressor, a driven fluid machine that raises low-pressure gas to high-pressure gas, is the heart of the refrigeration system. It draws in low-temperature, low-pressure refrigerant gas through the suction pipe, compresses it via a piston driven by a motor, and then discharges high-temperature, high-pressure refrigerant gas through the exhaust pipe, providing power for the refrigeration cycle. This achieves the refrigeration cycle of compression → condensation (heat release) → expansion → evaporation (heat absorption). When a gas has a certain pressure and temperature, it possesses potential energy (indicated by pressure) and kinetic energy (indicated by temperature); these two types of energy are collectively called internal energy. The main function of the expander is to utilize the adiabatic expansion of the gas within the expander to perform work on the surroundings, consuming the gas's own internal energy, thereby significantly reducing the gas's pressure and temperature to achieve the purpose of refrigeration and cooling.

[0089] The downhole active cooling thermoelectric generator provided in this application embodiment uses a high-pressure gas-filled cooling unit with a closed-loop pneumatic cooling system for regenerative cooling. In the chamber at the cold head, the expansion effect is greater than the compression effect, absorbing heat to form a low-temperature zone and generating cooling capacity. This cooling module effectively increases the temperature difference between the hot and cold ends of the cooling module, improving the thermoelectric generator efficiency.

[0090] In one implementation, reference is made to Figure 1The thermal management module 3 includes a heat-conducting cable 31 and a guide post 32. The heat-conducting cable 31 transfers cold energy to the cold surface of the thermoelectric generator 51, while the hot surface of the thermoelectric generator 51 obtains heat through contact with a heat source via the guide post 32. The heat source can be the inner wall of the pressure-bearing outer shell or the inner wall of the drill collar. In this configuration, all the cold energy of the heat-conducting cable 31 is transferred to the cold surface of the thermoelectric generator 51, ensuring efficient power generation by the power generation module 5.

[0091] The downhole active cooling thermoelectric generator provided in this application uses heat-conducting cables and guide columns to provide stable heat and cold energy transfer to the device, which can ensure that the cold side of the thermoelectric generator absorbs cold energy efficiently and the hot side absorbs heat fully.

[0092] In one embodiment, the heat-conducting cable 31 and the guide post 32 are made of a material with good thermal conductivity. For example, the heat-conducting cable 31 is made of copper and multilayer graphene, and the guide post 32 is made of copper.

[0093] In some possible implementations, the heat-conducting cable 31 and the guide post 32 may be made of other materials with good thermal conductivity, and this application does not limit this.

[0094] In one possible implementation, such as Figure 5 As shown, the top of the guide post 32 is an arc surface that is in close contact with the heat source surface, thus fully absorbing the heat from the heat source surface.

[0095] The downhole active cooling thermoelectric generator provided in this application embodiment is equipped with a thermal management module for the conduction of heat and cold. In terms of materials, the heat conduction cable is made of copper and multilayer graphene, the guide post is made of copper, and the top of the guide post is set as an arc surface. These features enable the thermal management module to maximize the heat or cold transfer performance.

[0096] In one implementation, continue to refer to Figure 1 , Figure 3 as well as Figure 6 The power generation module 5 also includes a transformer chip 52, which is used to convert the electricity generated by the thermoelectric generator 51 into the voltage available to the drilling instrument 41.

[0097] Specifically, the transformer chip 51 has the following functions: It can achieve precise control of the power supply by adjusting the output voltage and current of the transformer, thereby improving the stability and accuracy of the power supply; it can reduce transformer losses and improve energy utilization efficiency by optimizing parameters such as the transformer's operating point and voltage waveform; it can monitor and protect the circuit, promptly stopping the circuit's operation when abnormal conditions such as overcurrent or overvoltage occur, protecting the transformer and other equipment; and in some specific applications, the transformer chip 51 can make the transformer more adaptable to specific needs, achieving precise control and measures.

[0098] In one embodiment, the power generation module 5 may be equipped with other circuits or modules for converting the electricity generated by the thermoelectric generator 51 into a voltage usable by the drilling instrument 41, and this application does not limit this.

[0099] The downhole active cooling thermoelectric generator provided in this application embodiment has a transformer chip in the power generation module to convert the electricity generated by the thermoelectric generator into a voltage usable by the drilling instrument, thus ensuring a stable power supply for the drilling instrument.

[0100] In one implementation, such as Figure 6 As shown, the thermal management module 3 transfers cooling energy to the drilling instrument control module 4. The thermal management module 3 includes a heat-conducting cable 31 and a guide post 32. The heat-conducting cable 31 is close to the drilling instrument control module 4, transferring cooling energy to it. The cold side of the thermoelectric generator 51 is close to the drilling instrument control module 4 to obtain cooling energy, while the hot side of the thermoelectric generator 52 contacts the heat source through the guide post 32 to obtain heat.

[0101] The drilling instrument control module 4 is installed between the heat-conducting cable 31 and the thermoelectric generator 51. The heat-conducting cable 31 first transfers the cooling energy generated by the cooling module 2 to the drilling instrument control module 4, cooling it to a relatively low temperature. The cold side of the thermoelectric generator 51 absorbs cooling energy from the drilling instrument control module 4, while the hot side is connected to the heat source. The temperature difference between the cold and hot sides triggers the Seebeck effect, thereby generating electricity. The generated electricity is further converted into a voltage usable by the drilling instrument control module through a transformer chip, providing a stable power supply for the drilling instrument.

[0102] In this configuration, the cooling energy of the heat-conducting cable 31 is supplied not only to the power generation module 5, but also to the drilling instrument circuit module 4 to maintain a low temperature. This configuration is suitable for high-temperature and ultra-high-temperature environments. When the ambient temperature exceeds the operating temperature of the drilling instrument 41, this configuration can ensure the normal operation of the drilling instrument 41.

[0103] The active cooling thermoelectric generator provided in this application ensures that the instrument's circuitry maintains a low temperature in high and ultra-high temperature environments by placing the instrument's control module between the heat-conducting cable and the thermoelectric generator, thus preventing abnormal operation of the instrument's circuitry due to excessive temperature.

[0104] In one implementation, reference is made to Figure 1The cooling module 2, thermal management module 3, drilling instrument electrical control module 4, and power generation module 5 are all housed within a sealed pressure-bearing housing 6. In the power transmission module 1, the turbine stator 11, turbine rotor 12, turbine drive shaft, and first gear are located outside the pressure-bearing housing 6 and come into contact with the drilling fluid during operation to obtain the kinetic energy of the drilling fluid. The second gear 15 and magnetic coupler 16 are located inside the pressure-bearing housing 6.

[0105] The pressure-bearing outer shell 6 is made of a material resistant to high temperature and pressure, which can provide pressure support and a certain degree of high-temperature isolation for the downhole active cooling thermoelectric generator. This application does not limit the specific materials used to manufacture the pressure-bearing outer shell 6.

[0106] The downhole active cooling thermoelectric generator provided in this application embodiment has a pressure-bearing outer shell that provides pressure support and thermal isolation for the cooling module, thermal management module, drilling instrument electrical control module and power generation module, ensuring that these modules operate stably in the downhole environment.

[0107] Figure 7 This is a schematic diagram of the downhole power generation system provided in this application. The downhole power generation system includes a drill collar 8 and Figure 8 The diagram shows a downhole active cooling thermoelectric generator. The drill collar 8 has a side compartment, and the downhole active cooling thermoelectric generator is installed inside the compartment 81. The downhole active cooling thermoelectric generator can be accessed by opening the side compartment cover 82.

[0108] The drill collar, located at the bottom of the drill string, is a key component of the lower drill string assembly. It possesses significant gravity and rigidity, helping the drill bit maintain stability during drilling, reducing vibration and impact, thereby improving drilling efficiency and quality. During drilling, drilling fluid enters the drill collar through its cylinder. The turbine module installed inside the drill collar rotates under the influence of the drilling fluid, converting the fluid's kinetic energy into mechanical energy to power the subsequent cooling module.

[0109] In one implementation, multiple side chambers can be opened in the drilling rig, and each side chamber is equipped with a set of... Figure 8 The downhole active cooling thermoelectric generator shown shares a single turbine module with multiple units. Specifically, the turbine stator 11, turbine rotor 12, and turbine drive rod are shared by multiple units. The first gear 14 of all units is connected to the same turbine drive rod. Drilling fluid is guided by the turbine stator 11 to impact the turbine rotor 12, causing it to rotate. This rotation, in turn, drives multiple first gears 14 via the turbine drive rod, thus providing kinetic energy to the multiple downhole active cooling thermoelectric generators.

[0110] In one implementation, the hot surface, such as Figure 9 As shown, this application provides a downhole power generation system, including a drill collar 8 and as shown in the figure. Figure 1 The downhole active cooling thermoelectric generator shown is described. The downhole active cooling thermoelectric generator is designed according to... Figure 1 The device is configured such that the heat-conducting cable 31 directly contacts the power generation module 5, providing cooling to the module. The drilling instrument control module 4 does not directly contact the heat-conducting cable 31 or the power generation module 5; instead, it transmits the voltage output from the transformer chip 52 to the drilling instrument 41 via the wire 42. The aforementioned downhole active cooling thermoelectric generator is installed in the side compartment 81 of the drill collar 8, and can be accessed by opening the side compartment cover 82. Similarly, multiple side compartments can be opened in this drill collar 8 to install multiple downhole active cooling thermoelectric generators. These multiple generators share a single turbine module, which is powered by the drilling fluid impacting the turbine module during drilling.

[0111] In one implementation, such as Figure 10 As shown, this application provides a downhole power generation system, including a drill collar 8 and Figure 3 The image shows a downhole active cooling thermoelectric generator. Figure 3 In the active cooling thermoelectric generator shown, the power transmission module 1 is equipped with a turbine stator 11 and a turbine rotor 12. A magnetic coupling device is installed on the end face of the turbine rotor 12. The drilling fluid flows through the turbine stator 11 and impacts the turbine rotor 12. The rotation of the turbine rotor 12 generates an alternating magnetic field. The downhole cooling unit 21 in the cooling module 2 is magnetically coupled to the turbine rotor 12. When the turbine rotor 12 rotates, the downhole cooling unit 21 rotates synchronously with it, thereby driving the internal compressor and expansion agent to cool. In this configuration, the turbine drive rod, the first gear 14, and the second gear 15 are eliminated, resulting in higher kinetic energy transmission efficiency. The above-mentioned downhole active cooling thermoelectric generator is installed at the off-center position of the drill collar 8 through a positioning ring. This ensures that the downhole power generation module obtains sufficient kinetic energy while minimizing the resistance of the drill collar 8 during the drilling process.

[0112] The downhole power generation system provided in this application consists of a downhole drill collar and a downhole active cooling thermoelectric generator. It can adapt to harsh environments such as high temperatures during oil and gas extraction. During drilling, it provides stable power to the drilling instruments through active cooling and thermoelectric power generation, ensuring the continuous and stable operation of the oil and gas extraction process.

[0113] The overall cost of the downhole active cooling thermoelectric generator and system provided in this application embodiment is far lower than that of traditional power generation methods such as turbine generators and downhole lithium battery power supply. In practical applications, maintenance costs and operational difficulty are also relatively low. It can replace traditional downhole power generation technologies that cannot generate power in high-temperature downhole environments, and its cost is far lower than commonly used methods such as traditional lithium battery packs or turbine generators, further implementing the concept of cost reduction and efficiency improvement. The above technology is not only suitable for the exploration and development of resources such as oil and natural gas, but can also be applied to other geological exploration fields requiring high-precision advance exploration, such as mineral resource exploration and underground engineering surveys.

[0114] In response to the needs of existing ultra-deep and ultra-high temperature wells, the innovative achievements of this invention can be tested and applied in relevant complex blocks both domestically and internationally. Related fields of the device and system proposed in this invention include active downhole cooling technology for drilling instruments. The cooling capacity generated by the refrigeration device can cool the drilling instrument and other downhole instruments, thereby increasing the temperature resistance of the downhole instruments themselves and further contributing to the advancement of exploration and development technologies for deep oil and gas reservoirs.

[0115] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A downhole active cooling thermoelectric generator, characterized in that, include: Power transmission module, cooling module, thermal management module, drilling instrument electrical control module, and power generation module; The power transmission module is magnetically coupled to the refrigeration module, and is used to drive the refrigeration module to generate cooling capacity using downhole fluid as a kinetic energy source. The cooling module is used for cooling, providing cooling capacity to the power generation module and the drilling instrument module; The thermal management module transfers cooling energy to the power generation module; The power generation module includes at least one thermoelectric generator connected in series with the drilling instrument control module, used to generate electricity using temperature difference, and to supply power to the drilling instrument control module and the drilling instrument mounted on the drilling instrument control module. The cooling module includes: a downhole drilling chiller and a cold head; The downhole chiller is magnetically coupled to the power transmission module, and generates cooling capacity under the drive of the power transmission module. The generated cooling capacity is transferred by the cold head. The downhole refrigeration unit uses a closed pneumatic refrigeration unit for regenerative refrigeration. It consists of a magnetically driven compressor and an expansion mechanism. In the chamber at the cold head, the expansion effect is greater than the compression effect, absorbing heat to form a low-temperature zone for refrigeration. The thermal management module includes: a heat-conducting cable and a guide post; the cold side of the thermoelectric generator is close to the heat-conducting cable to obtain cooling energy, and the hot side of the thermoelectric generator is in contact with the heat source through the guide post to obtain heat; all the cooling energy of the heat-conducting cable is transferred to the cold side of the thermoelectric generator; or, The thermal management module transmits cooling energy to the drilling instrument control module; the thermal management module includes: a heat-conducting cable and a guide post; The heat-conducting cable is close to the drilling instrument control module and transfers cooling energy to the drilling instrument control module. The cold side of the thermoelectric generator is close to the electrical control module of the drilling instrument to obtain cooling, while the hot side of the thermoelectric generator is in contact with the heat source through the guide post to obtain heat.

2. The downhole active cooling thermoelectric generator according to claim 1, characterized in that, The power transmission module includes: a turbine stator and a turbine rotor; The turbine rotor has a built-in magnetic coupling device; the turbine stator is used to guide the inflowing liquid so that the liquid impacts the turbine rotor, driving the turbine rotor and the magnetic coupling device to rotate, and causing the magnetic coupling device to generate an alternating magnetic field.

3. The downhole active cooling thermoelectric generator according to claim 1, characterized in that, The power transmission module includes: a turbine stator, a turbine rotor, a turbine drive shaft, a first gear, a second gear, and a magnetic coupler; The first gear is mounted on the turbine drive shaft; the first gear meshes with the second gear; the second gear is rigidly connected to the magnetic coupler. The turbine stator and the turbine rotor are used to convert the kinetic energy of the flowing liquid into mechanical energy, driving the turbine drive shaft and the first gear to rotate. The second gear and the magnetic coupler rotate under the drive of the first gear, causing the magnetic coupler to generate an alternating magnetic field.

4. The downhole active cooling thermoelectric generator according to claim 1, characterized in that, The heat-conducting cable is made of copper and multilayer graphene.

5. The apparatus according to claim 1, characterized in that, The guide post is made of copper. And / or, the top end of the guide post is an arc surface that is in close contact with the surface of the heat source.

6. The downhole active cooling thermoelectric generator according to any one of claims 1 to 3, characterized in that, The power generation module also includes a transformer chip, which is used to convert the electricity generated by the thermoelectric generator into the voltage available to the drilling instrument.

7. The downhole active cooling thermoelectric generator according to any one of claims 1 to 3, characterized in that, The refrigeration module, the thermal management module, the drilling instrument electrical control module, and the power generation module are all housed within a sealed pressure-bearing housing.

8. A downhole power generation system, characterized in that, include: The drill collar and the downhole active cooling thermoelectric generator as described in any one of claims 1 to 7.

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