Underground electric energy and signal wireless transmission device

Abstract

The invention relates to the field of oil and gas well intelligent well completion downhole tools, and discloses a downhole electric energy and signal wireless transmission device which comprises a wireless signal transmission master control module, a power circuit, a single-core cable communication circuit, a wireless signal transmission module and a wireless electric energy transmission coil. The wireless signal transmission main control module is connected with the power supply circuit and is used for controlling the power supply circuit to work; the wireless electric energy transmission coil performs magnetic energy and electric energy conversion on the received voltage through the Faraday's law of electromagnetic induction, rectifies the converted electric energy and outputs the rectified electric energy; the single-core cable communication circuit, the wireless signal transmission module and the power supply circuit are connected with the wireless electric energy transmission coil, and all circuits, sensors and motors of three underground layer sections are supplied with power, so that wireless electric energy transmission is realized. According to the invention, the normal output and transmission of signals can be realized, and the transmission precision and reliability are high.

Description

Technical Field

[0001] The present invention relates to the field of intelligent downhole completion tools for oil and gas wells, and in particular to a downhole wireless power and signal transmission device. Background Art

[0002] In the harsh environment of oil and gas wells, the high-temperature and high-pressure oil, gas and water mixed medium in the well often causes the contact copper rings of the male and female heads of the conventional plug-in wet joints of intelligent well completion to have poor contact due to sand sticking, wax deposition, corrosion, etc., resulting in failure of power and signal transmission. Therefore, it is necessary to provide a wireless transmission device for power and signals in the well that is not affected by the mixed fluid in the wellbore to solve the above problems. Summary of the invention

[0003] In view of the above problems, the purpose of the present invention is to provide an underground power and signal wireless transmission device. Through the coordinated use of an underground wireless signal transmission circuit and a flexible coil, normal signal output and transmission can be achieved, and it has high transmission accuracy and reliability.

[0004] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: an underground electric energy and signal wireless transmission device, which includes: a wireless signal transmission main control module, a power supply circuit, a single-core cable communication circuit, a wireless signal transmission module and a wireless power transmission coil; the wireless signal transmission main control module is connected to the power supply circuit to control the operation of the power supply circuit; the wireless power transmission coil converts the received voltage into magnetic energy and electrical energy through Faraday's law of electromagnetic induction, and rectifies the converted electrical energy and outputs it to power the single-core cable communication circuit, the wireless signal transmission module, the power supply circuit and all circuits, sensors and motors in the three layers of the underground connected to the wireless power transmission coil, thereby realizing wireless power transmission.

[0005] Furthermore, it also includes a DC boost circuit and a full-bridge inverter circuit; The DC boost circuit is used to boost the input voltage and transmit it to the full-bridge inverter circuit to convert the boosted DC voltage into AC power, and then connect the AC power to the wireless power transmission coil.

[0006] Further, a boost detection is performed at the output end of the DC boost circuit, and the detected signal is transmitted to the wireless signal transmission main control module; an output voltage detection is performed at the output end of the full-bridge inverter circuit, and the detected signal is transmitted to the wireless signal transmission main control module; The wireless signal transmission main control module is a microcontroller, which controls the operation of the full-bridge inverter circuit according to the received detection signal.

[0007] Furthermore, the full-bridge inverter circuit is a single-phase inverter circuit, including four MOS tubes, which form two half-bridge circuits. The upper and lower MOS tubes of the same bridge arm are turned on alternately, and the cross-line switch tubes are turned on at the same time.

[0008] Furthermore, it also includes an isolation gate driver; the input end of the isolation gate driver is connected to the output end of the wireless signal transmission main control module, and the drive signal output by the wireless signal transmission main control module is amplified and input into the full-bridge inverter circuit.

[0009] Furthermore, the DC boost circuit boosts the input voltage and converts it twice in sequence, then outputs a 5V DC voltage to the isolation transformer. After being output from the isolation transformer, the voltage is converted again into a 3.3V DC voltage to power the wireless signal transmission main control module.

[0010] Furthermore, it also includes a rectifier circuit, which includes a bridge rectifier and a voltage stabilizing circuit; the bridge rectifier is a full-wave rectifier circuit composed of four diodes, which rectifies the AC voltage output by the wireless power transmission coil, and then filters and stabilizes it through two parallel capacitors before outputting it.

[0011] Furthermore, the wireless signal transmission main control module adopts ST's STM32F410CBT6 processor.

[0012] Further, the wireless power transmission coil includes a magnet, a transmitting coil and a receiving coil; The magnet is located at the center and has a ring-shaped structure; The transmitting coil is arranged on the outer circumference of the magnet, and the receiving coil is arranged on the outer circumference of the transmitting coil, and there is a gap between the receiving coil and the transmitting coil; Both the receiving coil and the transmitting coil use flexible coils.

[0013] Furthermore, the magnet is composed of a plurality of rod-shaped ferrites to serve as the magnetic core of the transmitting coil; and the receiving coil uses PEEK as a skeleton.

[0014] The present invention adopts the above technical solution, which has the following advantages: The wireless power transmission device of the present invention is composed of a wireless signal transmission main control circuit, a 3.3V power supply circuit, an RS485 communication circuit and a transmission coil. The input DC voltage is converted into AC power after a boost and inverter circuit, and wireless power transmission is realized through a transmitting coil and a receiving coil. Finally, power is provided to subsequent sensors to ensure the reliable operation of the system, realize normal output and transmission of signals, and have high transmission accuracy and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1Schematic diagram of the overall structure of the underground electric energy and signal wireless transmission device in an embodiment of the present invention; Figure 2 is a schematic diagram of wireless power transmission in an embodiment of the present invention; Figure 3 is a schematic diagram of a single-phase inverter circuit in an embodiment of the present invention; Figure 4 is a rectifier circuit in an embodiment of the present invention; Figure 5 is a schematic diagram of the structure of a wireless power transmission coil in an embodiment of the present invention; Figure 6 yes Figure 5 Side view of. DETAILED DESCRIPTION

[0016] In order to solve the problem of antenna deviation and signal loss, the present invention provides an underground power and signal wireless transmission device, an underground wireless signal transmission circuit and a main control program with an integrated flexible antenna, which realizes circuit installation and signal wireless transmission in a small space, and solves the problem of antenna deviation and signal loss. The present invention adopts an electromagnetic induction wireless power transmission method, which greatly improves the reliability of the overall system.

[0017] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0018] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0019] In one embodiment of the present invention, a device for wirelessly transmitting underground electric energy and signals is provided. Figure 1 As shown, the device includes: a wireless signal transmission main control module, a power supply circuit, a single-core cable communication circuit, a wireless signal transmission module and a wireless power transmission coil.

[0020] The wireless signal transmission main control module is connected to the power circuit and is used to control the operation of the power circuit; The wireless power transmission coil converts the received voltage into magnetic energy and electrical energy through Faraday's law of electromagnetic induction, and rectifies the converted electrical energy for output to power the single-core cable communication circuit, wireless signal transmission module, power supply circuit and all circuits, sensors and motors in the three layers of the well connected to the wireless power transmission coil, thereby realizing wireless power transmission.

[0021] RS485 communication is adopted between the single-core cable communication circuit and the wireless signal transmission module.

[0022] In the above embodiment, Figure 2 As shown, the underground power and signal wireless transmission device of the present invention also includes a DC boost circuit and a full-bridge inverter circuit. The DC boost circuit is used to boost the input 80-110V voltage to a 160V DC voltage, and transmit it to the full-bridge inverter circuit to convert the 160V DC voltage into AC, and the AC is connected to the wireless power transmission coil.

[0023] Among them, boost detection is performed at the output end of the DC boost circuit, and the detected signal is transmitted to the wireless signal transmission main control module; output voltage detection is performed at the output end of the full-bridge inverter circuit, and the detected signal is transmitted to the wireless signal transmission main control module.

[0024] The wireless signal transmission main control module is a microcontroller, which controls the operation of the full-bridge inverter circuit according to the received detection signal.

[0025] like Figure 2 As shown, the electric energy output from the receiving coil in the wireless power transmission coil powers the connected single-core cable communication circuit, wireless signal transmission circuit, and all circuits, sensors, and motors in the three layers of the well. The maximum total power of each sensor, motor, and circuit board in a single layer is 18.425W, and the maximum total power of the three layers working simultaneously is 55.275W, 2.4W for the single-core cable communication circuit, 0.5W for the wireless signal transmission circuit, and at least 58.175W for the wireless power receiving coil, rounded to 60W.

[0026] like Figure 3 As shown, the full-bridge inverter circuit is a single-phase inverter circuit, including four MOS tubes, which form two half-bridge circuits. The upper and lower MOS tubes of the same bridge arm are turned on alternately, and the cross-line switch tubes are turned on at the same time. The inductor L1, capacitor C13 and resistor R4 are connected to the output end of the bridge arm. Among them, the MOS tube is a switch. As long as the speed is fast enough (the switching frequency is high enough), the on and off time (charging and discharging time) is controlled well, and the output filter capacitor is used, a basically stable Vo, that is, the output voltage, can be obtained. When the switch is turned on, the inductor L1 is grounded, the diode is cut off, the input voltage Vi charges the inductor L1, and the voltage across the inductor is Vi, and the energy of the input voltage is stored in the inductor L1.

[0027] When the switch becomes non-conductive, since the inductor L1 has been charged before, current flows to the right, and the current at both ends of the inductor cannot change suddenly, a voltage will be induced, causing the diode on the right side of the MOS tube to conduct, thereby supplying power to the output load. In addition, the input voltage can also provide energy to the output through the inductor, so the purpose of boosting can be achieved.

[0028] Since the boost capability of the boost circuit is related to the on and off of the MOS, the duty cycle is defined as D. The boost capability of the boost circuit can be changed by changing the duty cycle.

[0029] The single-phase full-bridge inverter circuit has the following advantages: (1) Simplicity: The circuit structure of the single-phase inverter circuit is simpler than that of the multi-phase inverter circuit because only one inverter bridge is required. This makes design, implementation and maintenance easier. (2) Low cost: Due to the simple circuit structure, fewer components and materials are required, so the cost is relatively low. This makes the single-phase inverter circuit more competitive in some low-cost applications. (3) Wide applicability: The single-phase inverter circuit is suitable for many application scenarios, such as household appliances, low-power UPS systems, power tools, etc. Their simplicity and low cost enable them to play a role in many fields. (4) High reliability: Due to the simple structure of the single-phase inverter circuit, it is usually more reliable than the complex multi-phase inverter circuit. Therefore, the number of components and connection points are reduced through the single-phase full-bridge inverter circuit, thereby reducing the possibility of failure.

[0030] When working, when Q1 and Q4 are turned on, the circuit outputs a positive input voltage, and when Q2 and Q3 are turned on, the circuit outputs a reverse output voltage, thereby achieving the purpose of outputting alternating positive and negative AC voltages on the load side. Since the voltage signal output by the controller needs to be amplified for the MOS to work properly, an isolated gate driver is used to amplify the drive signal.

[0031] In this embodiment, the input end of the isolation gate driver is connected to the output end of the microcontroller, and the driving signal output by the microcontroller is amplified and then input into the full-bridge inverter circuit.

[0032] Among them, the isolated gate driver can use SI8233, which is a chip that integrates high-performance half-bridge driver and isolator functions. Half-bridge driver function: SI8233 has two independent half-bridge drivers that can be used to control half-bridge power devices (such as MOSFET or IGBT). This makes SI8233 suitable for motor drive, power conversion and other applications that require half-bridge drive. SI8233 has an internal integrated isolator function that can provide signal isolation and electrical isolation, so that there is electrical isolation between the input signal and the output signal. This isolation function helps to improve the safety and stability of the system while reducing the number of external components and the complexity of the system. High-speed drive SI8233 has a fast driving capability and can achieve fast switching conversion, thereby improving the response speed and efficiency of the system. Low-power SI8233 adopts a low-power design, which can maintain a low power consumption level during operation, which helps to improve the energy efficiency and battery life of the system. Built-in protection function: SI8233 has a variety of protection functions integrated inside, including over-current protection, over-temperature protection, under-voltage lockout protection, etc., which can effectively protect the chip and system from damage. Wide operating temperature range: SI8233 can work normally in a wide operating temperature range and is suitable for various industrial and automotive electronic application environments. Standard package: SI8233 chip adopts common standard package, which is easy to integrate and layout in various circuit board designs.

[0033] In this embodiment, the DC boost circuit boosts the input 80-110V voltage and converts it twice in sequence, then outputs a 5V DC voltage to the isolation transformer. After being output from the isolation transformer, the voltage is converted again into a 3.3V DC voltage to power the microcontroller.

[0034] The two voltage conversions are 110VDC to 12VDC and 12VDC to 5VDC respectively.

[0035] The above embodiment also includes a rectifier circuit. The electric energy output by the wireless power transmission coil is alternating current, which is rectified by the rectifier circuit and then output to facilitate normal power supply for subsequent circuits and sensors.

[0036] like Figure 4 As shown, the rectifier circuit includes a bridge rectifier and a voltage stabilizing circuit. The bridge rectifier is a full-wave rectifier circuit composed of four diodes D1-D4, which rectifies the 160VAC AC voltage output by the wireless power transmission coil, and then filters and stabilizes it through two parallel capacitors C3 and C4 before outputting it.

[0037] The rectifier circuit rectifies the 160VAC AC voltage output by the wireless power transmission coil and converts it into 48VDC, 12VDC, and 5VDC.

[0038] In the above embodiment, the wireless signal transmission main control module adopts the STM32F410CBT6 processor of ST Company, and the STM32F410 product line is an entry-level product of the STM32 F4 series.

[0039] Specifically, the STM32F410 takes full account of the balance between performance and power efficiency, and highly integrates built-in memory and various peripherals. The package can be as small as 2.553 x 2.579 mm, which can be widely used in cost-effective applications such as medical, industrial and consumer. The STM32F410 is based on the Cortex-M4 core with a floating-point unit, with an operating frequency of up to 100 MHz, and can achieve excellent low-power performance in both running and shutdown modes. At a frequency of 100 MHz, using ST's ART accelerator, when executing from Flash memory, the STM32F410 can achieve zero-wait execution of FLASH and achieve a performance of 125 DMIPS / 339CoreMark. DSP instructions and floating-point units expand the application range of the product. This series of products uses ST's 90 nm process and ART accelerator, with dynamic power adjustment function.

[0040] In the above embodiment, the wireless power transmission coil is crucial in the entire wireless power transmission process. Figure 5 , Figure 6 As shown, the wireless power transmission coil includes a magnet 1, a transmitting coil 2 and a receiving coil 3. The magnet 1 is located at the center and has a ring structure; the transmitting coil 2 is arranged on the outer circumference of the magnet 1, and the receiving coil 3 is arranged on the outer circumference of the transmitting coil 2, and there is a gap between the receiving coil 3 and the transmitting coil 2.

[0041] In this embodiment, preferably, the gap between the receiving coil 3 and the transmitting coil 2 is 5 mm.

[0042] In this embodiment, the magnet 1 is composed of a plurality of rod-shaped ferrites, which serve as the magnetic core of the transmitting coil 2. The receiving coil 3 uses PEEK as a skeleton. The coil assembly structure is optimized, and the transmission efficiency reaches more than 60%.

[0043] In this embodiment, both the receiving coil 3 and the transmitting coil 2 are flexible coils.

[0044] When in use, the stable direct current output by the DC voltage source is transmitted to the inverter circuit and converted into alternating current. The alternating current generates an alternating magnetic field through the transmitting coil 2. When the receiving coil 3 is coupled with the transmitting coil 2, according to Faraday's law of electromagnetic induction, the receiving coil 3 will generate an induced electromotive force and an induced current at the same time, thereby completing the conversion of magnetic energy into electrical energy. After rectification, it is converted into direct current to power the corresponding equipment, thereby realizing wireless power transmission.

[0045] In summary, when the present invention is used, the input voltage of 80-110V is increased to a DC voltage of 160V through a boost circuit, and the 160V DC voltage is converted into AC power by a single-phase bridge inverter circuit; then the AC power is connected to the transmitting end of the wireless coil, and is transmitted to the receiving end of the coil according to Faraday's law of electromagnetic induction; after the AC power is received at the receiving end according to the induction law, it is rectified by a full-wave rectifier circuit composed of diodes, and the rectified DC power provides power for devices such as sensors.

[0046] The present invention can realize normal output and transmission of signals through the coordinated use of the underground wireless signal transmission circuit and the flexible coil, and has high transmission accuracy and reliability.

[0047] The present invention adopts wireless mode to transmit electric energy, which greatly improves the reliability of the overall system. The working principle of electromagnetic induction wireless power transmission: through the electromagnetic induction principle of the coil, the function of wireless transmission of electric energy from the transmitting coil to the receiving coil is realized.

[0048] The present invention can convert the input DC voltage into AC power after passing through the boost and inverter circuits, and transmit and deliver the AC power through the wireless coil, thereby maintaining reliable and safe power supply for subsequent sensor modules.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An underground power and signal wireless transmission device, characterized in that: include: Wireless signal transmission main control module, power supply circuit, single-core cable communication circuit, wireless signal transmission module and wireless power transmission coil; The wireless signal transmission main control module is connected to the power circuit and is used to control the operation of the power circuit; The wireless power transmission coil converts the received voltage into magnetic energy and electrical energy through Faraday's law of electromagnetic induction, and rectifies the converted electrical energy for output to power the single-core cable communication circuit, wireless signal transmission module, power supply circuit and all circuits, sensors and motors in the three layers of the well connected to the wireless power transmission coil, thereby realizing wireless power transmission.

2. The underground electric energy and signal wireless transmission device as claimed in claim 1, characterized in that: It also includes a DC boost circuit and a full-bridge inverter circuit; The DC boost circuit is used to boost the input voltage and transmit it to the full-bridge inverter circuit to convert the boosted DC voltage into AC power, and then connect the AC power to the wireless power transmission coil.

3. The underground electric energy and signal wireless transmission device as claimed in claim 2, characterized in that: Performing voltage boost detection at the output end of the DC boost circuit, and transmitting the detected signal to the wireless signal transmission main control module; performing output voltage detection at the output end of the full-bridge inverter circuit, and transmitting the detected signal to the wireless signal transmission main control module; The wireless signal transmission main control module is a microcontroller, which controls the operation of the full-bridge inverter circuit according to the received detection signal.

4. The underground electric energy and signal wireless transmission device as claimed in claim 2, characterized in that: The full-bridge inverter circuit is a single-phase inverter circuit, including four MOS tubes. The four MOS tubes form two half-bridge circuits. The upper and lower MOS tubes of the same bridge arm are turned on alternately, and the cross-line switch tubes are turned on at the same time.

5. The underground electric energy and signal wireless transmission device as claimed in claim 2, characterized in that: It also includes an isolation gate driver; the input end of the isolation gate driver is connected to the output end of the wireless signal transmission main control module, and the drive signal output by the wireless signal transmission main control module is amplified and then input into the full-bridge inverter circuit.

6. The underground electric energy and signal wireless transmission device as claimed in claim 2, characterized in that: The DC boost circuit boosts the input voltage and converts it twice in sequence, then outputs a 5V DC voltage to the isolation transformer. After being output from the isolation transformer, it is converted again into a 3.3V DC voltage to power the wireless signal transmission main control module.

7. The underground electric energy and signal wireless transmission device as claimed in claim 1, characterized in that: It also includes a rectifier circuit, which includes a bridge rectifier and a voltage stabilizing circuit; the bridge rectifier is a full-wave rectifier circuit composed of four diodes, which rectifies the AC voltage output by the wireless power transmission coil, and then filters and stabilizes it through two parallel capacitors before outputting it.

8. The underground electric energy and signal wireless transmission device as claimed in claim 1, characterized in that: The wireless signal transmission main control module uses ST's STM32F410CBT6 processor.

9. The underground electric energy and signal wireless transmission device as claimed in claim 1, characterized in that: The wireless power transmission coil includes a magnet, a transmitting coil and a receiving coil; The magnet is located at the center and has a ring structure; The transmitting coil is arranged on the outer circumference of the magnet, and the receiving coil is arranged on the outer circumference of the transmitting coil, and there is a gap between the receiving coil and the transmitting coil; Both the receiving coil and the transmitting coil use flexible coils.

10. The underground electric energy and signal wireless transmission device as claimed in claim 9, characterized in that: The magnet is composed of multiple rod-shaped ferrites to serve as the magnetic core of the transmitting coil; the receiving coil uses PEEK as the skeleton.

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