Novel downhole power and communication circuit and method

Abstract

This invention provides a novel downhole power supply and communication circuit and method. The circuit includes a surface control cabinet, an AC cable, a wireless upper connector, a wireless lower connector, a DC cable, and a downhole intelligent device. The surface control cabinet loads AC power and AC communication signals onto the AC cable. The AC cable carries the AC power and AC communication signals and transmits them via PLC AC carrier to the wireless upper connector. The wireless upper connector transmits the received AC power and AC communication signals to the oil-water space via radio electromagnetic signals. The wireless lower connector receives the radio electromagnetic signals transmitted by the wireless upper connector and converts them into DC power and DC communication signals, which are then sent to the DC cable. The DC cable transmits the DC power and DC communication signals via PLC DC carrier to the downhole intelligent device. This invention enables a power line carrier method combining cable + wireless and AC carrier + DC carrier from the wellhead to the well bottom, reducing production costs.

Description

Technical Field

[0001] This invention relates to the field of downhole communication technology in oil extraction, and in particular to a novel downhole power supply and communication circuit and method. Background Technology

[0002] In the process of oil extraction, the development of downhole monitoring and control technology for oil and water wells is the most important step in building smart oilfields. The development and application of downhole monitoring and control technology rely on the development of wired and wireless communication technologies. Currently, DC carrier communication technology uses single-core cables to power and communicate with downhole intelligent tools, supporting long-life real-time monitoring and control in production wells. However, with the increasing demands for reliability and long service life in oil extraction processes, the field has proposed the need for segmented downhole production tubing, necessitating a shift from cable communication to wireless power supply and communication. Furthermore, when using electric pumps in production wells, to simplify the number of external tubing cables, it has been proposed that the electric pump cables be used simultaneously for powering downhole intelligent tools and transmitting communication signals, thus requiring improvements based on the demands of the construction process.

[0003] Patent CN116006139B relates to a cabled intelligent injection system using wireless power transmission, comprising a surface controller, a tubing section, and a tool section. The tubing section includes tubing and a surface cable. The tool section includes a downhole controller and several layers of cabled intelligent injection units. A cabled wireless transmission section is installed between the tubing section and the tool section. The upper end of the cabled wireless transmission section is connected to the surface controller and the wellhead Christmas tree via the surface cable and tubing, respectively. The lower end of the cabled wireless transmission section is connected to the downhole controller. After receiving downlink communication commands from the surface controller via the cabled wireless transmission section, the downhole controller sends them to the cabled intelligent injection units via cable carrier communication. Simultaneously, the downhole controller receives uplink response data signals from each layer of cabled intelligent injection units and transmits them to the cabled wireless transmission section. The cabled wireless transmission section then sends the data back to the surface controller via cable carrier communication. This invention's cabled intelligent injection system can achieve wireless power transmission and two-way wireless data communication with high communication efficiency.

[0004] Patent CN113794491B discloses an intelligent electromagnetic interference suppression device for deep-well power line carrier communication. The device includes a carrier module, a power line, a coupling device, a current transformer module, a variable micro-inductance anti-interference module, a surface power supply, a downhole power supply, and a common zero-point loop module. The coupling device and the variable micro-inductance anti-interference module are connected in series between the power line and the surface and downhole power supplies. The variable micro-inductance anti-interference module can adaptively adjust the inductance value of the variable micro-inductor in real time based on the external line current measured by the current transformer module, avoiding interference from high-order harmonics in the line to the carrier signal. The common zero-point loop connects the negative terminals of the surface and downhole power supplies to the ground wire of the power line, ensuring they have the same relative zero point and preventing the influence of different relative zero points on the carrier signal. A heat dissipation device is installed on the carrier module to quickly release heat into the environment, improving its service life.

[0005] Patent CN106884636A discloses a wireless power supply intelligent monitoring and control system for water injection wells based on the principle of frequency interoperability. It includes a water injection tubing, a storage-type integrated intelligent water distributor, a downhole stratified flow real-time monitoring and adjustment instrument, and a surface control system. The water distributor is located inside the water injection tubing, and both the water distributor and the monitoring and adjustment instrument are connected to the surface control system. The monitoring and adjustment instrument includes a power wireless transmitting module and a first wireless communication module. The water distributor includes an interconnected power wireless receiving module and a second wireless communication module, which can achieve bidirectional data communication wirelessly. When the water distributor and the monitoring and adjustment instrument are close together, the power wireless transmitting module and the power wireless receiving module can match in a frequency interoperability manner. This invention enables wireless power supply, wireless communication, and real-time control of the water distributor, ensuring automatic downhole regulation of the water injection system, improving monitoring and adjustment efficiency and water injection quality, and effectively reducing the number of retrieval operations, thus saving injection and production costs.

[0006] The aforementioned comparative patents disclose a wired intelligent injection system using wireless power transmission, a wired intelligent injection system using wireless power transmission, and a wireless power supply intelligent monitoring and control system for water injection wells based on the principle of cross-frequency interaction. These mainly describe the wireless power supply circuit topology and system framework, which differ from the circuit structure and function used in this invention. All of the above prior art differs significantly from this invention. A search reveals no literature in the XY category, indicating that this invention possesses innovation. Since existing technologies do not offer solutions to the technical problems we seek to address, we have invented a novel downhole power supply and communication circuit and method. Summary of the Invention

[0007] The purpose of this invention is to provide a novel downhole power supply and communication circuit and method that can be applied in electric pump oil production + downhole multi-layer intelligent stratified oil production tubing, enabling the use of a power line carrier method with cable + wireless and AC carrier + DC carrier from the wellhead to the bottom of the well.

[0008] The objective of this invention can be achieved through the following technical measures: a novel downhole power supply and communication circuit, comprising a surface control cabinet, an AC cable, a wireless upper connector, a wireless lower connector, a DC cable, and a downhole intelligent device. The surface control cabinet loads AC power and AC communication signals onto the AC cable. The AC cable carries AC power and AC communication signals and transmits them via PLC AC carrier to the wireless upper connector. The wireless upper connector transmits the received AC power and AC communication signals to the oil-water space via radio electromagnetic signals. The wireless lower connector receives the radio electromagnetic signals transmitted by the wireless upper connector and converts them into DC power and DC communication signals, which are then sent to the DC cable. The DC cable transmits the DC power and DC communication signals via PLC DC carrier to the downhole intelligent device.

[0009] The objective of this invention can also be achieved through the following technical measures:

[0010] The ground control cabinet includes an AC power supply module and a first AC carrier modulation and demodulation module. The AC power supply module generates AC power and transmits the AC power to the downhole through the AC cable and the wireless connector. The first AC carrier modulation and demodulation module performs AC carrier modulation and demodulation to obtain an AC communication signal and loads the AC communication signal onto the AC cable.

[0011] This AC cable is a pump cable and can transmit three-phase AC power.

[0012] The wireless connector includes a wireless transceiver coil that couples AC power and AC communication signals to the wireless transceiver coil and transmits them to the oil and water space via radio electromagnetic signals.

[0013] The wireless lower connector is located in the oil-water space and includes a wireless transceiver lower coil, a rectifier-filtered DC power supply module, a second AC carrier modulation and demodulation module, a first central control CPU module, and a first DC carrier modulation and demodulation module. The wireless transceiver lower coil couples the AC power and AC communication signals transmitted from the wireless upper connector to the oil-water space to the wireless transceiver lower coil. The rectifier-filtered DC power supply filters and rectifies the AC power on the wireless transceiver lower coil into DC power, supplying power to the second AC carrier modulation and demodulation module, the first central control CPU module, and the first DC carrier modulation and demodulation module in the wireless lower connector. Simultaneously, the rectifier-filtered DC power supply... The DC power supply module with current filtering provides DC power for the PLC DC carrier transmission of the downhole intelligent device; the second AC carrier modulation and demodulation module communicates bidirectionally with the first AC carrier modulation and demodulation module in the ground control cabinet; the first central control CPU module unifies the data format and communication rate of the second AC carrier modulation and demodulation module and the first DC carrier modulation and demodulation module, realizing bidirectional communication between the two modules; the first DC carrier modulation and demodulation module is used to realize bidirectional communication with the downhole intelligent device.

[0014] The DC cable is a single-core DC steel pipe cable, which is connected to the rectifier and filter DC power supply module and the first DC carrier modulation and demodulation module to provide DC power supply and bidirectional communication for the downhole intelligent equipment.

[0015] The downhole intelligent device includes a filtered DC power supply module, a second DC carrier modulation and demodulation module, a second central control CPU module, and a test and control module. The filtered DC power supply module converts the DC power on the DC cable into stable DC power and provides DC power to the second DC carrier modulation and demodulation module, the second central control CPU module, and the test and control module. The second DC carrier modulation and demodulation module demodulates the DC communication signal on the DC cable and sends it to the second central control CPU module. The second DC carrier modulation and demodulation module and the first DC carrier modulation and demodulation module in the wireless connector achieve bidirectional communication through the DC cable. The second central control CPU module is used to unify the data format and communication rate of the second DC carrier modulation and demodulation module and the test and control module, and to achieve bidirectional communication between the two modules. The test and control module includes sensors and motors for downhole multi-parameter testing and motor control.

[0016] The number of the downhole intelligent devices is one or more. When there are multiple downhole intelligent devices, the multiple downhole intelligent devices are connected in parallel between the core wire and the outer armor of the DC cable, and each production layer corresponds to one downhole intelligent device.

[0017] The objective of this invention can also be achieved through the following technical measures: a novel downhole power supply and communication method, which employs a novel downhole power supply and communication circuit, comprising:

[0018] Step 1: The ground control cabinet loads AC power and AC communication signals onto the AC cable;

[0019] Step 2: The AC cable transmits AC power and AC communication signals to the wireless connector via PLC AC carrier transmission.

[0020] Step 3: The wireless connector transmits the incoming AC power and AC communication signals to the oil and water space via wireless electromagnetic signals;

[0021] Step 4: The wireless lower connector receives the radio electromagnetic signal sent by the wireless upper connector and converts it into DC power and DC communication signal, which are then sent to the DC cable;

[0022] Step 5: The DC cable transmits the DC power and DC communication signals to the downhole intelligent equipment via PLC DC carrier, realizing bidirectional data communication.

[0023] The objective of this invention can also be achieved through the following technical measures:

[0024] In step 5, there are multiple downhole intelligent devices connected in parallel between the core wire and the outer armor of the DC cable, with one downhole intelligent device corresponding to each production layer.

[0025] The novel downhole power supply and communication circuit and method of this invention can be applied in electric pump oil production + downhole multi-layer intelligent stratified oil production tubing. It can realize the connection of various downhole electrical tools with a single cable and wireless transceiver coil from the wellhead to the bottom of the well using a power line carrier method of cable + wireless and AC carrier + DC carrier. At the same time, it realizes the power supply and communication of various downhole electrical equipment, simplifies the construction difficulty of laying multiple cables outside the tubing, reduces construction costs, and also improves the flexibility of the tubing and realizes the segmentation of the tubing. Compared with existing technologies, this invention has the following advantages: it enables the connection of all electrical equipment and intelligent monitoring and control equipment in the production well from the wellhead to the downhole using a single cable, solving the problem of the difficulty of laying multiple cables on the construction tubing and reducing tubing costs; it enables wireless transmission of power supply and communication signals, and allows for segmentation of the production tubing. For processes requiring disconnection of upper and lower tubing layers, this increases the flexibility of the process tubing, reduces production and operating costs, and expands the application scope of intelligent monitoring and control technology; and it integrates the communication signals of various intelligent devices downhole onto a single cable, reducing the number of cables and lowering production costs. Attached Figure Description

[0026] Figure 1This is a circuit debugging schematic diagram of a specific embodiment of the novel downhole power supply and communication circuit of the present invention;

[0027] Figure 2 A flowchart illustrating a specific embodiment of the novel downhole power supply and communication method of the present invention;

[0028] In the diagram, 1-Ground control cabinet, 1-1 AC power supply, 1-2 AC carrier modulation and demodulation, 2-AC cable, 3-Wireless upper connector, 4-Wireless lower connector, 4-1 Wireless transceiver lower coil, 4-2 Rectifier and filter DC power supply, 4-3 AC carrier modulation and demodulation, 4-4 Central control CPU, 4-5 DC carrier modulation and demodulation, 5-DC cable, 6-Downhole intelligent equipment, 6-1 Filtered DC power supply, 6-2 DC carrier modulation and demodulation, 6-3 Central control CPU, 6-4 Test and control module. Detailed Implementation

[0029] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0030] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, and / or combinations thereof.

[0031] The novel downhole power supply and communication circuit of the present invention comprises six parts: a surface control cabinet, an AC cable, a wireless upper connector, a wireless lower connector, a DC cable, and downhole intelligent equipment.

[0032] The surface control cabinet is used to generate AC power and modulate AC carrier waves, and is responsible for sending electrical energy downhole and loading signals onto AC cables.

[0033] AC cables are carriers of three-phase AC power, carrying AC communication signals for PLC (Power Line Carrier) AC carrier transmission.

[0034] The wireless connector wirelessly transmits the AC power and carrier signal from the AC cable to the oil and water space via a coil.

[0035] The wireless connector is located in the oil and water space, receives radio electromagnetic signals and converts them into DC current and communication signals, and transmits them to the DC cable using DC carrier wave.

[0036] DC power and carrier signals are transmitted over DC cables for PLC (Power Line Carrier) DC carrier transmission.

[0037] There are usually one or more intelligent devices in the well, connected to a DC carrier cable, for multi-parameter testing and control of moving parts in the production layer; the entire communication system can realize bidirectional communication of uplink and downlink, as well as power supply from top to bottom.

[0038] This invention employs a power line carrier method combining cable and wireless communication, as well as AC and DC carrier communication, to connect various underground electrical tools from the wellhead to the mine using a single cable and wireless transceiver coils. This simultaneously enables power supply and communication for all underground electrical equipment. The invention utilizes a dedicated DC / AC carrier communication mode conversion module and a dedicated AC / DC power supply mode conversion method.

[0039] Existing technologies typically employ wired DC carrier waves for communication and power supply to downhole intelligent equipment, AC carrier waves for power supply to electric pumps and multi-parameter testing downhole, and wireless power supply and communication via electromagnetic coupling with wet connectors. This invention combines these three methods, enabling the application of DC carrier waves, AC carrier waves, wireless communication, and power supply to a single cable. This satisfies both the power and communication requirements of different downhole power supply equipment and the need for disconnection between production tubing and lifting tubing.

[0040] The following are several specific embodiments of the application of the present invention.

[0041] Example 1: A novel downhole power supply and communication circuit

[0042] A new type of downhole power supply and communication circuit: such as Figure 1 As shown, a new type of downhole power supply and communication circuit includes six parts: a surface control cabinet 1, an AC cable 2, a wireless upper connector 3, a wireless lower connector 4, a DC cable 5, and downhole intelligent equipment 6.

[0043] The ground control cabinet 1 is used to generate AC power and modulate AC carrier waves, and is responsible for sending electrical energy downhole and loading signals onto AC cables.

[0044] AC cable 2 is a carrier of three-phase AC power, carrying AC communication signals for PLC (Power Line Carrier) AC carrier transmission.

[0045] Wireless connector 3 transmits the AC power and carrier signal from the power cable to the oil and water space wirelessly via a coil.

[0046] Wireless connector 4 receives radio electromagnetic signals and converts them into DC and communication signals, which are then transmitted to the DC cable using a DC carrier wave.

[0047] DC power and carrier signals are transmitted on DC cable 5 for PLC (Power Line Carrier) DC carrier transmission.

[0048] There are usually one or more downhole intelligent devices 6 connected to a DC carrier cable, which are used for multi-parameter testing and control of moving parts in the production layer; the entire communication system can realize bidirectional communication between uplink and downlink, as well as power supply from top to bottom.

[0049] The ground control cabinet 1 includes two functional modules: AC power supply 1-1 and AC carrier modulation and demodulation 1-2. The AC power supply 1-1 circuit provides AC power to the downhole equipment, while the AC carrier modulation and demodulation 1-2 module is used for bidirectional communication with the downhole equipment.

[0050] The AC cable 2 is an electric pump cable that can transmit three-phase AC power, and the AC carrier signal is coupled onto the three-phase AC power by the AC carrier modulation and demodulation module inside the control cabinet.

[0051] The wireless connector 3 is composed of a spiral wireless transceiver coil 3-1, which is used to couple AC power and AC carrier signal to the spiral coil and transmit them to the oil-water space.

[0052] The wireless lower connector 4 consists of five modules: a wireless transceiver lower coil 4-1, a rectifier-filtered DC power supply 4-2, an AC carrier modulation and demodulation module 4-3, a central control CPU 4-4, and a DC carrier modulation and demodulation module 4-5. The wireless transceiver lower coil 4-1 couples the electrical energy and communication signals transmitted from the wireless transceiver upper coil 3-1 into the wireless transceiver lower coil 4-1. The rectifier-filtered DC power supply 4-2 filters and rectifies the AC signal on the wireless transceiver lower coil 4-1 into DC power, supplying power to the AC carrier modulation and demodulation module 4-3, the central control CPU 4-4, and the DC carrier modulation and demodulation module 4-5 in the wireless lower connector 4. Simultaneously, the rectifier-filtered DC power supply 4-2 provides power to the downhole intelligent device 6 via a PLC (Power Line Carrier). (er) DC power supply section for DC carrier transmission; AC carrier modulation and demodulation 4-3 and AC carrier modulation and demodulation 1-2 in ground control cabinet 1 realize bidirectional AC carrier communication; central control CPU 4-4 is used for data format and communication rate unification, and realizes bidirectional communication between the two modules AC carrier modulation and demodulation 4-3 and DC carrier modulation and demodulation 4-5; DC carrier modulation and demodulation 4-5 is used to realize bidirectional communication with downhole intelligent equipment.

[0053] The upper wireless transceiver coil is wound on the first C-shaped magnetic core. The lower wireless transceiver coil is wound on the second C-shaped magnetic core; the first and second C-shaped magnetic cores are the same size and shape, and their C-end faces can fit together; the upper and lower wireless transceiver coils are coupled by the magnetic coupling of the two C-shaped magnetic cores to achieve bidirectional transmission of power supply signals and communication signals.

[0054] The DC cable 5 is a single-core DC steel pipe cable that transmits DC power and communication signals. The DC cable 5 is connected to the rectifier and filter DC power supply 4-2 circuit of the wireless connector 4; the DC cable 5 is also connected to the DC carrier modulation and demodulation 4-5 to provide DC power supply and bidirectional communication for the downhole intelligent equipment.

[0055] The downhole intelligent device 6 consists of four parts: a filtered DC power supply 6-1, a DC carrier modulation and demodulation 6-2, a central control CPU 6-3, and a testing and control module 6-4. The filtered DC power supply 6-1 module converts the DC power on the DC cable 5 into stable DC power, because the power on the DC cable is DC power plus a carrier wave, which cannot be directly used for DC power supply due to the fluctuation of the carrier wave, causing instability in the DC power supply. Therefore, filtering is necessary. It also provides DC power to the DC carrier modulation and demodulation 6-2, the central control CPU 6-3, and the testing and control module 6-4. The DC carrier modulation and demodulation 6-2 demodulates the communication signal on the DC cable 5 and sends it to the central control CPU 6-3. The DC carrier modulation and demodulation 6-2 and the DC carrier modulation and demodulation 4-5 achieve bidirectional communication through the DC cable 5. The central control CPU 6-3 is used for data format and communication rate unification, enabling bidirectional communication between the DC carrier modulation and demodulation 6-2 and the testing and control module 6-4. The testing and control module 6-4 contains sensors and motors for downhole multi-parameter testing and motor control.

[0056] like Figure 2 As shown, the new downhole power supply and communication method includes:

[0057] Step 1: The ground control cabinet loads AC power and AC communication signals onto the AC cable;

[0058] Step 2: The AC cable transmits AC power and AC communication signals to the wireless connector via PLC AC carrier transmission.

[0059] Step 3: The wireless connector transmits the incoming AC power and AC communication signals to the oil and water space via wireless electromagnetic signals;

[0060] Step 4: The wireless lower connector receives the radio electromagnetic signal sent by the wireless upper connector and converts it into DC power and DC communication signal, which are then sent to the DC cable;

[0061] Step 5: The DC cable transmits the DC power and DC communication signals to the downhole intelligent equipment via PLC DC carrier transmission. Multiple downhole intelligent devices are connected in parallel between the core wire and outer armor of the DC cable, with one device corresponding to each production layer.

[0062] The power supply principle of the new downhole power supply and communication method is as follows: AC power supply 1-1 is loaded onto AC cable 2, transmitted to wireless upper connector 3 and wireless transceiver upper coil 3-1 and transmitted to the oil and water space. Wireless transceiver lower coil 4-1 in wireless lower connector 4 receives the wireless AC power supply signal, transmits it to rectified and filtered DC power supply 4-2, and powers each module inside wireless lower connector 4. Then, it powers the downhole intelligent device 6 through DC carrier cable 5.

[0063] The communication principle of the new downhole power supply and communication method: AC carrier modulation and demodulation module 1-2 realizes bidirectional half-duplex communication via AC cable 2, wireless transceiver upper coil 3-1, wireless transceiver lower coil 4-1, and AC carrier modulation and demodulation module 4-3; central control CPU 4-4 is used for data format and communication rate unification, realizing bidirectional communication between AC carrier modulation and demodulation module 4-3 and DC carrier modulation and demodulation module 4-5; DC carrier modulation and demodulation module 4-5 realizes bidirectional half-duplex communication via DC cable 5 and DC carrier modulation and demodulation module 6-2; central control CPU 6-3 is used for data format and communication rate unification, realizing bidirectional communication between DC carrier modulation and demodulation module 6-2 and test and control module 6-4; the entire system achieves bidirectional half-duplex communication from the control cabinet to the downhole intelligent equipment through a single cable.

[0064] Example 2: Application of Multiple Downhole Intelligent Devices in an Electric Pump Well

[0065] The AC cable is connected to the downhole electric pump, and multiple downhole intelligent devices are connected in parallel between the core wire and the outer armor of the DC cable. Each production layer corresponds to one downhole intelligent device, realizing multi-parameter testing of the entire wellbore with a single cable.

[0066] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0067] Except for the technical features described in the specification, all other technologies are known to those skilled in the art.

Claims

1. A novel downhole power supply and communication circuit, characterized in that, The new downhole power supply and communication circuit includes a surface control cabinet, an AC cable, a wireless upper connector, a wireless lower connector, a DC cable, and downhole intelligent equipment. The surface control cabinet loads AC power and AC communication signals onto the AC cable. The AC cable carries AC power and AC communication signals and transmits them via PLC AC carrier to the wireless upper connector. The wireless upper connector transmits the received AC power and AC communication signals to the oil and water space via radio electromagnetic signals. The wireless lower connector receives the radio electromagnetic signals transmitted by the wireless upper connector and converts them into DC power and DC communication signals, which are then sent to the DC cable. The DC cable transmits the DC power and DC communication signals via PLC DC carrier to the downhole intelligent equipment.

2. The novel downhole power supply and communication circuit according to claim 1, characterized in that, The ground control cabinet includes an AC power supply module and a first AC carrier modulation and demodulation module. The AC power supply module generates AC power and transmits the AC power to the downhole through the AC cable and the wireless connector. The first AC carrier modulation and demodulation module performs AC carrier modulation and demodulation to obtain an AC communication signal and loads the AC communication signal onto the AC cable.

3. The novel downhole power supply and communication circuit according to claim 1, characterized in that, This AC cable is a pump cable and can transmit three-phase AC power.

4. The novel downhole power supply and communication circuit according to claim 1, characterized in that, The wireless connector includes a wireless transceiver coil that couples AC power and AC communication signals to the wireless transceiver coil and transmits them to the oil and water space via radio electromagnetic signals.

5. The novel downhole power supply and communication circuit according to claim 2, characterized in that, The wireless lower connector is located in the oil-water space and includes a wireless transceiver lower coil, a rectifier-filtered DC power supply module, a second AC carrier modulation and demodulation module, a first central control CPU module, and a first DC carrier modulation and demodulation module. The wireless transceiver lower coil couples the AC power and AC communication signals transmitted from the wireless upper connector to the oil-water space to the wireless transceiver lower coil. The rectifier-filtered DC power supply filters and rectifies the AC power on the wireless transceiver lower coil into DC power, supplying power to the second AC carrier modulation and demodulation module, the first central control CPU module, and the first DC carrier modulation and demodulation module in the wireless lower connector. Simultaneously, the rectifier-filtered DC power supply... The DC power supply module with current filtering provides DC power for the PLC DC carrier transmission of the downhole intelligent device; the second AC carrier modulation and demodulation module communicates bidirectionally with the first AC carrier modulation and demodulation module in the ground control cabinet; the first central control CPU module unifies the data format and communication rate of the second AC carrier modulation and demodulation module and the first DC carrier modulation and demodulation module, realizing bidirectional communication between the two modules; the first DC carrier modulation and demodulation module is used to realize bidirectional communication with the downhole intelligent device.

6. The novel downhole power supply and communication circuit according to claim 5, characterized in that, The DC cable is a single-core DC steel pipe cable, which is connected to the rectifier and filter DC power supply module and the first DC carrier modulation and demodulation module to provide DC power supply and bidirectional communication for the downhole intelligent equipment.

7. The novel downhole power supply and communication circuit according to claim 5, characterized in that, The downhole intelligent device includes a filtered DC power supply module, a second DC carrier modulation and demodulation module, a second central control CPU module, and a test and control module. The filtered DC power supply module converts the DC power on the DC cable into stable DC power and provides DC power to the second DC carrier modulation and demodulation module, the second central control CPU module, and the test and control module. The second DC carrier modulation and demodulation module demodulates the DC communication signal on the DC cable and sends it to the second central control CPU module. The second DC carrier modulation and demodulation module and the first DC carrier modulation and demodulation module in the wireless connector achieve bidirectional communication through the DC cable. The second central control CPU module is used to unify the data format and communication rate of the second DC carrier modulation and demodulation module and the test and control module, and to achieve bidirectional communication between the two modules. The test and control module includes sensors and motors for downhole multi-parameter testing and motor control.

8. The novel downhole power supply and communication circuit according to claim 1, characterized in that, The number of the downhole intelligent devices is one or more. When there are multiple downhole intelligent devices, the multiple downhole intelligent devices are connected in parallel between the core wire and the outer armor of the DC cable, and each production layer corresponds to one downhole intelligent device.

9. A novel method for underground power supply and communication, characterized in that, The novel downhole power supply and communication method employs the novel downhole power supply and communication circuit described in claim 1, comprising: Step 1: The ground control cabinet loads AC power and AC communication signals onto the AC cable; Step 2: The AC cable transmits AC power and AC communication signals to the wireless connector via PLC AC carrier transmission. Step 3: The wireless connector transmits the incoming AC power and AC communication signals to the oil and water space via wireless electromagnetic signals; Step 4: The wireless lower connector receives the radio electromagnetic signal sent by the wireless upper connector and converts it into DC power and DC communication signal, which are then sent to the DC cable; Step 5: The DC cable transmits the DC power and DC communication signals to the downhole intelligent equipment via PLC DC carrier, realizing bidirectional data communication.

10. The novel downhole power supply and communication method according to claim 9, characterized in that, In step 5, there are multiple downhole intelligent devices connected in parallel between the core wire and the outer armor of the DC cable, with one downhole intelligent device corresponding to each production layer.

Images