A hydrid electro-mechanical control system for downhole sliding sleeves

Abstract

The application discloses a kind of for downhole sliding sleeve liquid electricity collaborative control system, including driving motor, for driving screw mechanism push valve open or close;Data acquisition module, including pressure acquisition unit, temperature acquisition unit and motor speed acquisition unit, for collecting front end pressure, temperature and driving motor speed data and feedback to MCU control module;MCU control module is used to receive the analog signal of data acquisition module, and processing and control;Power module is used to provide electric energy for system, and convert and output different voltage value electric energy.The system realizes valve action accurate synchronization and state tracing through closed-loop electric control, reduces artificial error and improves timeliness, automatically cuts off risk source when abnormal, reduces safety accident, realizes valve state digitization diagnosis;Early warning and protection mechanism judge risk in advance, deal with blocking and rotating quickly, fault response is reduced to minute level, can also optimize resource allocation to realize energy saving, meet high temperature and high pressure downhole intelligent mining demand.

Description

Technical Field

[0001] This application belongs to the technical field of oil and gas extraction equipment, specifically a hydraulic-electric co-control system for well slide sleeves. Background Technology

[0002] With the steady growth of the global economy, the demand for oil and gas, as a fundamental energy source, continues to rise. Conventional oil and gas reservoirs, after long-term large-scale exploitation, are gradually losing reserves, and the difficulty and cost of extraction are constantly increasing. To meet the ever-growing energy demand, oil extraction is moving towards intelligent and refined processes. Multi-layer stratified extraction technology has emerged as a core means to improve oil and gas recovery rates. By implementing differentiated extraction of different oil layers, oil and gas production can be effectively increased while reducing overall extraction costs. In the process of multi-layer stratified extraction, the wellbore casing, as a key flow control component, plays a crucial role, and its performance directly affects the extraction results.

[0003] Currently, the driving and control technology for downhole sleeves mainly relies on surface pump pressure pulses to drive the downhole piston. However, this traditional technology has many drawbacks. Due to the complex fluid environment downhole and the delay in pressure transmission, control commands issued from the surface take more than 30 minutes to receive an effective response downhole. In emergency situations, such as sudden blowouts or casing ruptures, such a long response delay greatly increases safety risks, making it impossible to take timely and effective intervention measures, potentially leading to serious production accidents and environmental pollution. Furthermore, this technology mainly relies on counting pressure pulses to adjust the sleeve opening. However, in actual operations, factors such as downhole pressure fluctuations, pulse signal attenuation, and equipment wear can cause the cumulative error of the pulse count to increase continuously, leading to sleeve opening positioning failure and preventing precise control of flow rates in each oil layer, severely impacting the effectiveness of stratified exploitation. Moreover, existing technology cannot verify the actual position of the sleeve in real time. When downhole faults such as sand jamming or wax deposition occur, the sleeve may fail to reach the intended position, but the surface control system cannot detect this in time. This not only reduces exploitation efficiency but may also trigger a series of downhole faults, increasing maintenance costs and operational risks. Utility Model Content

[0004] To address the aforementioned problems in existing technologies, this application provides a hydraulic-electric coordinated control system for well slide sleeves. This system controls the opening and closing of the motor via signals from a pressure sensor, thereby controlling the valve and solving the technical problems of lag in regulation and inability to provide real-time feedback in traditional pure hydraulic or mechanical slide sleeves.

[0005] To achieve the above objectives, this application adopts the following technical solution: a hydraulic-electric coordinated control system for a wellbore sliding sleeve, comprising:

[0006] A drive motor is used to drive a screw mechanism to open or close a valve. The drive motor includes a first motor connected to the oil inlet valve and a second motor connected to the oil return valve.

[0007] The data acquisition module includes a pressure acquisition unit, a temperature acquisition unit, and a motor speed acquisition unit, which are used to acquire data on front-end pressure, temperature, and drive motor speed and feed them back to the MCU control module;

[0008] The MCU control module is used to receive analog signals from the data acquisition module, and to process and control them. The MCU control module includes an ADC unit, which is used to monitor current signals, receive analog signals and convert them into digital signals.

[0009] The power module is used to provide electrical energy to the system and convert electrical energy into different voltage values ​​for output.

[0010] The pressure acquisition unit includes a pressure sensor and an amplifier connected between the pressure sensor and the MCU control module. The amplifier is used to amplify the weak pressure signal.

[0011] The power module includes a battery, a power switch, and two converters connected in sequence. The first converter is connected to the pressure sensor, and the second converter is connected to the amplifier, the temperature acquisition unit, and the serial port circuit.

[0012] The motor speed acquisition unit includes a position loop and a Hall sensor. The Hall sensor is used to acquire the speed of the drive motor, and the position loop is used to dynamically correct the operating state of the drive motor so that it accurately matches the target value.

[0013] The pressure acquisition unit is located in the front-end area of ​​the construction site, the motor speed acquisition unit is located on one side of the drive motor shaft, and the temperature acquisition unit is located around the MCU control module, the two motors, and the power supply module.

[0014] The hydraulic-electric co-control system also includes a data storage module, which is connected to the MCU control module and stores the pressure data signal, temperature data signal, and running time acquired by the data acquisition module.

[0015] The hydraulic-electric co-control system also includes a clock module, which records temperature data signals, pressure data signals, and the running time of the drive motor and sends them back to the MCU control module.

[0016] The hydraulic-electric coordinated control system also includes a fault alarm module, which is used to receive signals transmitted by the MCU control module and provide status and alarm feedback, including indicator lights, buzzers or wireless communication modules.

[0017] The beneficial effects of this application are:

[0018] A hydraulic-electric collaborative control system for wellbore sliding sleeves abandons traditional open-loop control logic and constructs a closed-loop control system of "state monitoring-feedback adjustment": by using the real-time motor operating parameters of the electronic control unit, the system understands the valve's motion status, dynamically adjusts the motor drive signal, and achieves precise synchronization and real-time status traceability of valve opening and closing actions, overcoming the shortcomings of "only execution, no monitoring" under open-loop control. Timed data acquisition, logical judgment, and automatic execution (valve / motor start / stop) replace frequent manual inspections and operations, standardizing the downhole hydraulic-electric control process, reducing human intervention errors, and improving control timeliness. Real-time monitoring of key parameters such as temperature (>150℃) and pressure (<90MPa) automatically puts the motor into hibernation when an anomaly is triggered, quickly cutting off the risk source and reducing the probability of equipment damage and downhole safety accidents caused by hydraulic-electric system anomalies.

[0019] In the power supply circuit of the valve drive motor, current signals are sampled in real time throughout the entire motor operation cycle (start-up, steady state, braking) through current detection, and a correlation mapping model between motor current and valve operating status is constructed. Utilizing the characteristics of "sudden current surge and waveform distortion" when the motor is stalled, amplitude analysis and harmonic detection of the current signal are used to determine whether the motor is stalled due to valve jamming, mechanical failure, or other reasons, thus achieving digital diagnosis of the valve's operating status.

[0020] Pre-set stall current thresholds and fault characteristic databases allow for early prediction of valve jamming risks, preventing escalation of faults. Abnormal data collection and automatic recording and storage of faults such as motor malfunction facilitate troubleshooting by maintenance personnel, shortening fault recovery cycles. Through a closed-loop "collection-judgment-execution" system, priority is given to critical operating conditions (such as prioritizing motor protection in case of abnormal pressure), optimizing downhole hydraulic and electrical resource allocation, reducing unnecessary energy consumption, and meeting the green mining requirements of "energy saving and efficiency improvement" in downhole operations. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the circuit principle of the liquid-electric coordinated control system of this application;

[0022] Figure 2 This is a schematic diagram of the motor closed-loop control process of the hydraulic-electric co-control system of this application;

[0023] Figure 3 This is a schematic diagram of the operation flow of the hydraulic-electric coordinated control system of this application;

[0024] In the diagram, 1—MCU control module, 2—drive motor, 3—clock module, 4—power module, 41—battery, 42—power system, 43—power switch, 5—data storage module, 6—temperature sensor, 7—pressure sensor, 8—amplifier, 9—fault alarm module, 10—motor drive module, 11—Hall sensor, 12—return encoder, 13—converter 1, 14—converter 2, 15—position loop. Detailed Implementation

[0025] Embodiments of this application will now be described in more detail with reference to the accompanying drawings. While embodiments of this application are shown in the drawings, it should be understood that this application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to make this application more thorough and complete, and to fully convey the scope of this application to those skilled in the art.

[0026] It should be understood that although the terms "first," "second," "third," etc., may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0027] In the description of this application, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0028] Unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0029] like Figure 1The hydraulic-electric coordinated control system for the well slide sleeve shown includes: a drive motor 2, a data acquisition module, an MCU control module 1, a power supply module 4, a data storage module 5, a clock module 3, and a fault alarm module 9.

[0030] The drive motor 2 is used to drive the screw mechanism to open or close the valve. Drive motor 2 includes a first motor and a second motor. The first motor is connected to the inlet valve, and the second motor is connected to the return valve. Drive motor 2 is connected to the MCU control module via the motor drive module 10. When drive motor 2 (either the first or second motor) receives a command from the MCU control module, its output shaft rotates (forward or reverse), providing power to the entire mechanism. The screw mechanism, consisting of a screw and a nut, is responsible for motion conversion and transmission. When drive motor 2 drives the screw to rotate, the nut's rotational freedom is restricted by structures such as guide rails, preventing it from rotating synchronously with the screw and moving linearly along the screw's axis. The nut is mechanically connected to the valve via a connecting rod or push rod. When the nut moves along the screw axis away from the valve's closed position, it applies a direct thrust through the connecting structure, causing the valve core or valve plate to deviate from the closed position, thus opening the valve. Reverse movement pulls the valve closed, thereby controlling the opening and closing of the inlet or return valve.

[0031] The data acquisition module includes a pressure acquisition unit, a temperature acquisition unit, and a motor speed acquisition unit. These units are used to acquire data on the front-end pressure, temperature, and drive motor speed 2, and feed this data back to the MCU control module 1. The temperature acquisition unit includes multiple temperature sensors 6 located around the MCU control module 1, around the two motors, and around the power supply module 4. The pressure acquisition unit is located in the construction front-end area and includes a pressure sensor 7 and an amplifier 8 positioned between the pressure sensor 7 and the MCU control module 1 to amplify the weak pressure signal.

[0032] The motor speed acquisition unit is located on one side of the shaft of the drive motor 2, such as... Figure 2 As shown, the system includes a position loop 15 and a Hall sensor 11. The Hall sensor 11 uses the Hall effect to detect the position of the motor rotor or load. Its working principle is as follows: when the motor rotates, the rotor's magnetic field periodically passes through the Hall element, causing its output voltage to change with the position, forming a pulse signal or analog signal corresponding to the position. The Hall sensor 11 accurately captures the actual position of the motor, converting the mechanical position information into an electrical signal to provide feedback to the position loop 15. The position loop 15, as the execution unit of the control algorithm, is responsible for comparing the position error between the "target position" and the "actual position," and outputting a control signal through calculation to drive the motor 2 to move in the direction that eliminates the error.

[0033] The target position is the position parameters (such as rotation angle, displacement distance, etc.) that the motor is expected to achieve, as set by the system. The actual position is the position state that the motor or load actually moves to, and its signal is detected by Hall sensor 11 and converted into an electrical signal, which is then sent back to position loop 15 for error calculation. When the actual position is close to the target position, position loop 15 will reduce the output signal to avoid motor overshoot; if the error increases, the control signal will be strengthened to speed up the adjustment, ultimately achieving stable position control.

[0034] When the system requires the drive motor 2 to actuate the valve at a specific speed, the Hall sensor 11 collects the current motor speed in real time and feeds it back to the position loop 15. The position loop 15 compares this speed with the target speed. If there is a deviation, it adjusts the motor's drive current or pulse frequency to bring the motor speed closer to the target value, thereby ensuring the accuracy and stability of the valve's operation. This closed-loop control mechanism is an important guarantee for achieving precise hydraulic-electric coordinated control of the downhole sleeve.

[0035] The MCU control module 1 includes an ADC unit, which is used to receive analog signals from the temperature acquisition unit, pressure acquisition unit and motor speed acquisition unit and convert them into digital signals. At the same time, the ADC unit is used to monitor the current signal.

[0036] Power module 4 provides electrical energy to the system and converts it into different voltage values. It includes a battery 41, power system 42, power switch 43, converter 13, and converter 14 connected in sequence. Converters 13 and 14 are two DC-DC step-down modules. Battery 41 provides 24V, and the two DC-DC step-down modules convert the 24V to 12V and 5V respectively. The 24V is first converted to 6V and then to 5V. The 12V voltage is passed to pressure sensor 7, and the 5V voltage is passed to amplifier 8, temperature acquisition unit, and serial port circuit. Power system 42 stabilizes, protects, and manages the voltage of battery 41, ensuring reliable power quality for subsequent circuits. Power switch 43 is a flow control valve, responsible for controlling whether power is supplied to the converters and downstream devices, realizing system power-on / off, safety protection, and energy consumption control. Clock module 3 records temperature data signals, pressure data signals, and the running time of drive motor 2 and sends the data back to MCU control module 1.

[0037] The data storage module 5 is electrically connected to the MCU control module 1 and stores the pressure data signal and temperature data signal acquired by the data acquisition module, as well as the corresponding running time.

[0038] The fault alarm module 9 receives signals transmitted from the MCU control module 1 and provides status and alarm feedback, including indicator lights, buzzers, or wireless communication modules. In this embodiment, throughout the entire software system operation cycle, the system's operating status is fed back to the operator in real time through a mechanism of alternating flashing of two LEDs. Specifically, the two LEDs alternately light up and turn off at a fixed frequency. When the system is operating normally, this alternating flashing will continue stably. If an abnormality occurs in the system, the flashing pattern will change or stop flashing, thus serving as a direct basis for judging the system's operating status.

[0039] When the current signal approaches the stall threshold, a light warning and system alarm are triggered to anticipate the risk of valve jamming and prevent the fault from escalating. Abnormal data collection and motor malfunctions are automatically recorded and stored, facilitating troubleshooting by maintenance personnel. This reduces fault response time from hours ("manual discovery → repair request") to minutes ("system automatic alarm → location"), shortening the fault recovery cycle. The retention of collected data, control commands, and fault records establishes a "digital archive" for the downhole electrohydraulic system, supporting later analysis of equipment operating patterns (such as pressure fluctuation cycles and motor load characteristics) and assisting in optimizing mining process parameters.

[0040] If a stall fault is detected (current characteristics match those of a stall fault), the electronic control unit immediately executes a "power cut-off + circuit protection" action: cutting off the motor power supply circuit to prevent overheating and insulation damage caused by prolonged stalling, thus preventing motor burnout; and linking with mechanical locking or redundant circuits to protect the lead screw drive mechanism, achieving closed-loop protection of equipment health status and reducing fault repair costs. Through the "collection-judgment-execution" closed loop, priority is given to ensuring critical operating conditions (such as prioritizing motor protection in case of abnormal pressure), optimizing the allocation of downhole hydraulic and electrical resources, reducing unnecessary energy consumption, and adapting to the green mining requirements of "energy saving and efficiency improvement" in downhole operations.

[0041] like Figure 3 As shown, the operation flow of the hydraulic-electric coordinated control system for the wellbore sliding sleeve is as follows:

[0042] Once the ground control terminal sends an open signal to the sliding sleeve, the entire control process officially begins. Pressure sensor 7 starts acquiring the pressure control open signal in real time. This pressure sensor 7 has high-precision acquisition capabilities, capable of capturing extremely minute pressure change signals. The acquired weak signal first enters amplifier 8 INA-129. INA-129 employs an advanced amplification circuit design, featuring low noise and high common-mode rejection ratio, enabling precise amplification of the minute signal to ensure no distortion during subsequent processing. The amplified signal is then transmitted to the ADC module. The ADC module uses a high-speed, high-precision conversion chip, capable of quickly and accurately converting analog signals into digital signals. The software system controls the sampling frequency and conversion accuracy of the ADC module to perform real-time analysis of the acquired digital signal, determining the signal's validity and the system's operating status based on preset logic rules.

[0043] Meanwhile, the ADC module also undertakes the crucial task of temperature signal acquisition. Temperature sensors (6) are deployed in key components such as the control board. These sensors monitor component temperatures in real time and transmit the temperature signals to the ADC module for conversion and processing. The software system incorporates temperature threshold judgment logic. When the temperature signal acquired by the ADC indicates that the component temperature does not exceed 150°C, the system determines that the temperature condition is met and allows the next step of logic processing. Conversely, if the temperature exceeds the threshold, the system will immediately stop overall operation and trigger an alarm mechanism, prompting operators to inspect and handle the situation to prevent equipment damage or safety accidents caused by high temperatures.

[0044] Under the premise of meeting the temperature conditions, the system continuously monitors and judges the pressure signal. When the pressure signal collected by the ADC exceeds the preset threshold of 90 MPa, the software system will output a high-frequency signal "1"; if the pressure signal does not reach the threshold, a low-frequency signal "0" will be generated. In order to more accurately analyze the changing trend and characteristics of the pressure signal, the system sets the signal acquisition time to a cycle of 5 minutes. Within each 5-minute cycle, the system generates a 6-bit signal sequence. When the generated 6-bit signal sequence is "01xx10", it meets the waveform conditions required by the system, and the system will start the motor. Among them, the first two "01" are defined as the start bit, used to identify the beginning of the signal sequence; the last two "10" are the stop bit, marking the end of the signal sequence; the middle two "xx" are the control bits, which can be configured according to actual needs to implement different control functions. The motor will only be started when the signal sequence completely conforms to the format "01xx10". This strict signal judgment mechanism effectively ensures the accuracy and reliability of motor starting.

[0045] Once the motor starting conditions are met, the system first starts the first motor and controls it to rotate forward. The first motor uses a high-performance drive circuit that provides stable torque output. The rotational motion of the first motor is connected to a lead screw mechanism via a coupling. The lead screw mechanism utilizes the principle of helical transmission to efficiently convert the motor's rotational motion into linear motion, thereby pushing the oil inlet valve open. During the operation of the first motor, the second motor remains stationary. To ensure the normal operation of the first motor, the system employs a dual monitoring mechanism: speed feedback and current feedback. After the first motor starts, the Hall sensor 11 mounted on the motor shaft collects the motor's speed signal in real time and transmits it to the control system. Simultaneously, the current detection section uses an ADC module for real-time monitoring. When the speed is consistently lower than the normal speed and a stall current is detected, the system determines that the first motor is not operating normally. At this time, the first motor will be immediately shut down, and the first motor start-up failure event will be recorded for subsequent fault analysis and troubleshooting. If the first motor is operating normally, the control system uses a closed-loop control method with a position loop 15. By continuously comparing the actual position of the motor with the desired position, the system adjusts the motor's speed and torque in real time, ensuring that the first motor's motion precisely reaches the desired value. During the operation of the first motor, the system continuously monitors its speed. Once the first motor has completed the required displacement, the system will enter the control phase of the second motor.

[0046] When the shutdown command is executed, the system first controls the first motor to reverse, closing the inlet valve. Then, it starts the second motor and controls it to rotate forward, thus opening the outlet valve. During the operation of the second motor, a speed monitoring mechanism is also employed. The second motor is equipped with the same Hall sensor 11 as the first motor, which collects the motor's speed and current signals in real time. After the second motor starts, the control system determines whether it is operating normally based on the speed and current feedback signals. If the second motor is not operating, i.e., its speed is consistently lower than normal and stall current is detected, the system will immediately shut down motor 2. If the second motor is operating normally, the control system uses a closed-loop control method with position loop 15, precisely adjusting the motor's speed and torque to achieve the desired movement. During the operation of the second motor, the system continuously monitors its speed, waiting for the second motor to open the return valve, completing the entire shutdown operation.

[0047] Finally, it should be noted that in this document, relationships such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "include," "contain," or any other variations are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0048] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0049] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A hydraulic-electric coordinated control system for a wellbore sliding sleeve, characterized in that, include: A drive motor is used to drive a screw mechanism to open or close a valve. The drive motor includes a first motor connected to the oil inlet valve and a second motor connected to the oil return valve. The data acquisition module includes a pressure acquisition unit, a temperature acquisition unit, and a motor speed acquisition unit, which are used to acquire data on front-end pressure, temperature, and drive motor speed and feed them back to the MCU control module; The MCU control module is used to receive analog signals from the data acquisition module, and to process and control them. The MCU control module includes an ADC unit, which is used to monitor current signals, receive analog signals and convert them into digital signals. The power module is used to provide electrical energy to the system and convert electrical energy into different voltage values ​​for output.

2. The hydraulic-electric coordinated control system for wellbore sliding sleeves as described in claim 1, characterized in that, The pressure acquisition unit includes a pressure sensor and an amplifier connected between the pressure sensor and the MCU control module. The amplifier is used to amplify the weak pressure signal.

3. The hydraulic-electric coordinated control system for wellbore sliding sleeves as described in claim 2, characterized in that, The power module includes a battery, a power switch, and two converters connected in sequence. The first converter is connected to the pressure sensor, and the second converter is connected to the amplifier, the temperature acquisition unit, and the serial port circuit.

4. The hydraulic-electric coordinated control system for wellbore sliding sleeves as described in claim 1, characterized in that, The motor speed acquisition unit includes a position loop and a Hall sensor. The Hall sensor is used to acquire the speed of the drive motor, and the position loop is used to dynamically correct the operating state of the drive motor so that it accurately matches the target value.

5. The hydraulic-electric coordinated control system for wellbore sliding sleeves as described in claim 1, characterized in that, The pressure acquisition unit is located in the construction front-end area, the motor speed acquisition unit is located on one side of the drive motor shaft, and the temperature acquisition unit is located around the MCU control module, around the two motors, and around the power supply module.

6. The hydraulic-electric coordinated control system for wellbore sliding sleeves as described in claim 1, characterized in that, The hydraulic-electric co-control system also includes a data storage module, which is connected to the MCU control module and stores the pressure data signal, temperature data signal, and running time acquired by the data acquisition module.

7. The hydraulic-electric coordinated control system for wellbore sliding sleeves as described in claim 1, characterized in that, The hydraulic-electric co-control system also includes a clock module, which records temperature data signals, pressure data signals, and the running time of the drive motor and sends them back to the MCU control module.

8. The hydraulic-electric coordinated control system for wellbore sliding sleeve as described in claim 1, characterized in that, The liquid-electric coordinated control system also includes a fault alarm module, which is used to receive signals transmitted by the MCU control module and provide status and alarm feedback, including indicator lights, buzzers or wireless communication modules.

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