An ultrasonic wave viscosity reduction closed loop feedback control system and method for crude oil in a well
Patent Information
- Application Number
- CN202611307424.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-26
- Publication Date
- 2026-10-23
AI Technical Summary
[0005]本申请的目的是提供一种井下原油超声波降粘闭环反馈控制系统及方法，以解决因缺乏闭环反馈机制而导致的降粘效果不稳定、能耗浪费及调节滞后的问题
本申请公开了一种井下原油超声波降粘闭环反馈控制系统及方法，通过井下粘度传感模块对井下原油粘度的实时采集、井下信号调理与通讯单元对粘度电信号的处理、控制器根据实测粘度与目标范围的偏差生成控制指令、超声波发射短节根据控制指令调节发射功率和占空比的完整闭环反馈链路，使超声发射参数能够跟随井下原油粘度的实时变化而自动、连续地调整，从而解决了因缺乏闭环反馈机制而导致的降粘效果不稳定、能耗浪费及调节滞后的问题。
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Figure CN122963051A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of oil and gas field development technology, and in particular to a closed-loop feedback control system and method for ultrasonic viscosity reduction of crude oil in downhole wells. Background Technology
[0002] In engineering applications of ultrasonic technology for downhole crude oil viscosity reduction, the physical properties of crude oil (such as viscosity, density, composition, and water cut) are not static. With changes in the well's production layer, fluctuations in formation pressure, increases in water cut, and the influence of different batches of chemical reagents, the rheological characteristics of crude oil within the wellbore undergo significant dynamic changes over time. Traditional ultrasonic viscosity reduction devices mostly employ an "open-loop" operating mode with preset fixed parameters (constant transmission power, frequency, and duty cycle). This mode is effective when crude oil properties are relatively stable, but once properties deviate—for example, if crude oil viscosity abnormally increases due to water emulsification—the fixed ultrasonic energy may be insufficient to achieve effective viscosity reduction, leading to lift failure. Conversely, if crude oil viscosity naturally decreases due to an increase in light components, excessive ultrasonic energy will result in ineffective energy consumption and accelerate transducer aging.
[0003] Many control schemes involving ultrasonic viscosity reduction focus on protecting the working state of the ultrasonic generator itself (such as shutting down due to overheating) or rely on manual adjustment based on ground sampling results. They lack a complete closed-loop scheme that can directly sense the true viscosity of the downhole fluid and feed this information back to the control system in real time to automatically and continuously adjust the ultrasonic emission parameters.
[0004] Therefore, there is an urgent need to provide a closed-loop feedback control system for ultrasonic viscosity reduction of downhole crude oil, which can sense the viscosity of downhole crude oil in real time and use the measured viscosity as feedback input to automatically and continuously adjust the ultrasonic emission parameters to form a complete closed-loop control link. Summary of the Invention
[0005] The purpose of this application is to provide a closed-loop feedback control system and method for ultrasonic viscosity reduction of downhole crude oil, in order to solve the problems of unstable viscosity reduction effect, energy waste and adjustment lag caused by the lack of a closed-loop feedback mechanism.
[0006] To achieve the above objectives, this application provides the following solution.
[0007] In a first aspect, this application provides a closed-loop feedback control system for ultrasonic viscosity reduction of crude oil in wells, comprising: a downhole viscosity sensing module, a downhole signal conditioning and communication unit, a surface control cabinet, and an ultrasonic transmitting subsection connected in sequence. The downhole viscosity sensing module is used to collect the viscosity electrical signal of the downhole crude oil in the working area of the ultrasonic transmitting sub in real time. The downhole signal conditioning and communication unit is used to amplify, filter and convert the viscosity electrical signal in real time to obtain the viscosity measurement value. The ground control cabinet has an embedded controller, which is used to generate control commands based on the viscosity measurement value and the preset target viscosity range. The ultrasonic transmitting section is used to adjust the ultrasonic transmitting parameters according to the control command to reduce the viscosity of downhole crude oil in the working area; the ultrasonic transmitting parameters include: transmitting power range and duty cycle.
[0008] In one embodiment, the downhole viscosity sensing module is a quartz crystal resonant viscosity sensor or a miniature vibration viscosity sensor.
[0009] In one embodiment, the housing of the downhole viscosity sensing module is made of a corrosion-resistant alloy.
[0010] In one embodiment, the sensitive element of the downhole viscosity sensing module is provided with an anti-deposition protective cover.
[0011] In one embodiment, a control command is generated based on the viscosity measurement value and a preset target viscosity range, including: When the measured viscosity value is greater than the upper limit of the preset target viscosity range, an instruction to increase ultrasonic energy is generated. When the viscosity measurement value is within the preset target viscosity range, an ultrasonic emission parameter unchanged control command is generated. When the measured viscosity value is less than the lower limit of the preset target viscosity range, a control command to reduce ultrasonic energy is generated.
[0012] In one embodiment, the command to increase ultrasonic energy includes a command to increase duty cycle and a command to increase transmission power; the command to decrease ultrasonic energy includes a command to decrease transmission power and a command to decrease duty cycle.
[0013] In one embodiment, the command to increase the duty cycle has a higher priority than the command to increase the transmit power; the command to decrease the transmit power has a higher priority than the command to decrease the duty cycle.
[0014] In one embodiment, the downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system further includes a ground human-machine interface; the ground human-machine interface is connected to the ground control cabinet; The ground-based human-machine interface is used for: Obtain the preset target viscosity range, preset transmission power range, and preset duty cycle range; The system displays the real-time values of the viscosity measurement and ultrasonic emission parameters.
[0015] In one embodiment, the controller incorporates a crude oil viscosity prediction model; the crude oil viscosity prediction model is obtained by training a long short-term memory network. The controller is also used to obtain the viscosity prediction value for each time period in the future based on the viscosity measurement value at each time of the historical period using the crude oil viscosity prediction model. Based on the predicted viscosity values at each time point in the future, control commands for each time point in the future are generated in advance.
[0016] Secondly, this application provides a downhole crude oil ultrasonic viscosity reduction closed-loop feedback control method, implemented based on the downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system, the downhole crude oil ultrasonic viscosity reduction closed-loop feedback control method comprising: Real-time acquisition of viscosity electrical signals of downhole crude oil within the working area of the ultrasonic transmitting sub; The viscosity electrical signal is amplified, filtered, and converted from analog to digital in real time to obtain the viscosity measurement value; Based on the measured viscosity value and the preset target viscosity range, control commands are generated; The ultrasonic emission parameters are adjusted according to the control command to reduce the viscosity of the downhole crude oil in the working area; the ultrasonic emission parameters include: emission power range and duty cycle.
[0017] According to the specific embodiments provided in this application, the following technical effects are disclosed: This application discloses a closed-loop feedback control system and method for ultrasonic viscosity reduction of downhole crude oil. The system utilizes a complete closed-loop feedback chain: a downhole viscosity sensing module for real-time acquisition of downhole crude oil viscosity; a downhole signal conditioning and communication unit for processing the viscosity electrical signal; a controller to generate control commands based on the deviation between the measured viscosity and the target range; and an ultrasonic transmitting section to adjust the transmission power and duty cycle according to the control commands. This allows the ultrasonic transmission parameters to be automatically and continuously adjusted in accordance with the real-time changes in downhole crude oil viscosity, thereby solving the problems of unstable viscosity reduction effect, energy waste, and adjustment lag caused by the lack of a closed-loop feedback mechanism. Attached Figure Description
[0018] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0019] Figure 1 This is a schematic diagram of the structure of a downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system provided in an embodiment of this application.
[0020] Figure label: Downhole viscosity sensing module—1, downhole signal conditioning and communication unit—2, surface control cabinet—3, ultrasonic transmitting sub—4, surface human-machine interface—5. Detailed Implementation
[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0022] The purpose of this application is to provide a closed-loop feedback control system and method for ultrasonic viscosity reduction of downhole crude oil, which aims to solve the problems of unstable viscosity reduction effect, energy waste and adjustment lag caused by the lack of a closed-loop feedback mechanism.
[0023] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0024] In one exemplary embodiment, such as Figure 1 As shown, a closed-loop feedback control system for ultrasonic viscosity reduction of crude oil in a well is provided, comprising: a downhole viscosity sensing module 1, a downhole signal conditioning and communication unit 2, a surface control cabinet 3, and an ultrasonic transmitting sub 4 connected in sequence. The downhole viscosity sensing module 1 is used to collect the viscosity electrical signal of the downhole crude oil in the working area of the ultrasonic transmitting sub 4 in real time. The downhole signal conditioning and communication unit 2 is used to amplify, filter and convert the viscosity electrical signal in real time to obtain the viscosity measurement value. The ground control cabinet 3 has an embedded controller, which is used to generate control commands based on the viscosity measurement value and the preset target viscosity range. The ultrasonic transmitting section 4 is used to adjust the ultrasonic transmitting parameters according to control commands to reduce the viscosity of downhole crude oil in the working area; the ultrasonic transmitting parameters include: transmitting power range and duty cycle.
[0025] Specifically, the downhole viscosity sensing module 1 is integrated onto the ultrasonic transmitting section 4, or installed adjacent to the ultrasonic transmitting section 4. The downhole signal conditioning and communication unit 2 is located near the downhole viscosity sensing module 1 and is connected to the surface control cabinet 3 via a dedicated signal line or power line in the armored cable.
[0026] As an optional implementation, the downhole viscosity sensing module 1 is a quartz crystal resonant viscosity sensor or a miniature vibration viscosity sensor.
[0027] As an optional implementation, the housing material of the downhole viscosity sensing module 1 is a corrosion-resistant alloy.
[0028] Specifically, corrosion-resistant alloys include, but are not limited to, Hastelloy C276.
[0029] As an optional implementation, the sensitive element of the downhole viscosity sensing module 1 is provided with an anti-deposition protective cover.
[0030] Specifically, the anti-deposition protective cover is in direct contact with the crude oil. The anti-deposition protective cover ensures the long-term online measurement accuracy of the downhole viscosity sensing module 1.
[0031] As an optional implementation, control commands are generated based on the viscosity measurement value and a preset target viscosity range, including: When the measured viscosity value exceeds the upper limit of the preset target viscosity range, an instruction to increase ultrasonic energy is generated. When the viscosity measurement value is within the preset target viscosity range, a control command is generated to keep the ultrasonic emission parameters unchanged. When the measured viscosity value is less than the lower limit of the preset target viscosity range, a control command to reduce ultrasonic energy is generated.
[0032] As an optional implementation, the ultrasonic energy control command increases the duty cycle control command and increases the transmission power control command; the ultrasonic energy control command decreases the transmission power control command and decreases the duty cycle control command.
[0033] As an optional implementation, the priority of the duty cycle control command is higher than that of the transmit power control command; the priority of the transmit power control command is higher than that of the duty cycle control command.
[0034] Specifically, when the viscosity measurement value exceeds the upper limit of the preset target viscosity range, it indicates insufficient viscosity reduction, and the controller generates an increase ultrasonic energy control command. The priority of the increase ultrasonic energy control command adjustment is as follows: first, execute the increase duty cycle control command to increase the duty cycle; if the duty cycle has been adjusted to the upper limit of the preset duty cycle range and is still not satisfactory, then execute the increase transmission power control command to increase the transmission power, until the viscosity measurement value falls back to the preset target viscosity range or the transmission power reaches the upper limit of the preset transmission power range.
[0035] When the viscosity measurement value is within the preset target viscosity range, it indicates that the viscosity reduction effect has met the standard, and the controller keeps the ultrasonic emission parameters unchanged.
[0036] When the viscosity measurement value is lower than the lower limit of the preset target viscosity range, it indicates that the crude oil may have been over-treated or that the viscosity of the crude oil itself is already very low. The controller generates a control command to reduce ultrasonic energy. The priority of the ultrasonic energy reduction control command is as follows: first, execute the control command to reduce the transmission power to reduce the transmission power; if the power has dropped to the lower limit of the preset transmission power range, then execute the control command to reduce the duty cycle to reduce the duty cycle, until the viscosity measurement value rises back to the preset target viscosity range.
[0037] As an optional implementation, the downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system also includes a ground human-machine interface 5; the ground human-machine interface 5 is connected to the ground control cabinet 3. Ground-based human-machine interface 5 is used for: Obtain the preset target viscosity range, preset transmit power range, and preset duty cycle range; Displays real-time values of viscosity measurements and ultrasonic emission parameters.
[0038] As an optional implementation, the controller incorporates a crude oil viscosity prediction model; the crude oil viscosity prediction model is obtained by training a long short-term memory network. The controller is also used to obtain the viscosity prediction values for future periods based on the viscosity measurements at each time point in historical periods using a crude oil viscosity prediction model. Based on the predicted viscosity values at each time point in the future, control commands for each time point in the future are generated in advance.
[0039] Specifically, taking a typical heavy oil well as an example, the upper limit of the preset target viscosity range is 300 mPa·s, and the lower limit is 200 mPa·s. The initial system operating parameters are: transmission power of 40 W, operating time of 1 s, and sleep time of 4 s (duty cycle 20%). During a certain period, due to a sudden increase in water cut, the crude oil forms a water-in-oil emulsion, and the viscosity measured by the online viscosity sensor instantly jumps to 450 mPa·s. The controller immediately activates Strategy 1, gradually reducing the sleep time from 4 s to 2 s (duty cycle 33%) within 10 seconds. At this point, the viscosity measurement drops to 320 mPa·s, still higher than the upper limit of the preset target viscosity range. The controller then continues to increase the transmission power from 40 W to 55 W, and the viscosity measurement subsequently stabilizes at around 250 mPa·s. The ultrasonic transmission parameters maintain operation under this new state. Several hours later, the emulsion broke down, and the viscosity naturally decreased to 180 mPa·s. The controller then initiated a command to reduce the ultrasonic energy, prioritizing the reduction of the transmission power from 55W to 35W, and the ultrasonic transmission parameters returned to a low-power state.
[0040] In one exemplary embodiment, a downhole crude oil ultrasonic viscosity reduction closed-loop feedback control method is provided, which is implemented based on a downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system. The downhole crude oil ultrasonic viscosity reduction closed-loop feedback control method includes: Real-time acquisition of viscosity electrical signals of downhole crude oil within the working area of the ultrasonic transmitting sub; The viscosity electrical signal is amplified, filtered, and converted from analog to digital in real time to obtain the viscosity measurement value; Based on the viscosity measurement value and the preset target viscosity range, control commands are generated; The ultrasonic emission parameters are adjusted according to the control command to reduce the viscosity of the downhole crude oil in the working area; the ultrasonic emission parameters include: emission power range and duty cycle.
[0041] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0042] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the system, method, and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A closed-loop feedback control system for ultrasonic viscosity reduction of crude oil in downhole wells, characterized in that, The downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system includes: a downhole viscosity sensing module, a downhole signal conditioning and communication unit, a surface control cabinet, and an ultrasonic transmitting subsection connected in sequence. The downhole viscosity sensing module is used to collect the viscosity electrical signal of the downhole crude oil in the working area of the ultrasonic transmitting sub in real time. The downhole signal conditioning and communication unit is used to amplify, filter and convert the viscosity electrical signal in real time to obtain the viscosity measurement value. The ground control cabinet has an embedded controller, which is used to generate control commands based on the viscosity measurement value and the preset target viscosity range. The ultrasonic transmitting section is used to adjust the ultrasonic transmitting parameters according to the control command to reduce the viscosity of the downhole crude oil in the working area; the ultrasonic transmitting parameters include: transmitting power range and duty cycle.
2. The downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system according to claim 1, characterized in that, The downhole viscosity sensing module is a quartz crystal resonant viscosity sensor or a miniature vibration viscosity sensor.
3. The downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system according to claim 1, characterized in that, The casing of the downhole viscosity sensing module is made of corrosion-resistant alloy.
4. The downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system according to claim 1, characterized in that, The sensitive element of the downhole viscosity sensing module is equipped with an anti-deposition protective cover.
5. The downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system according to claim 1, characterized in that, Based on the measured viscosity value and the preset target viscosity range, control commands are generated, including: When the measured viscosity value is greater than the upper limit of the preset target viscosity range, an instruction to increase ultrasonic energy is generated. When the viscosity measurement value is within the preset target viscosity range, an ultrasonic emission parameter unchanged control command is generated. When the measured viscosity value is less than the lower limit of the preset target viscosity range, a control command to reduce ultrasonic energy is generated.
6. The downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system according to claim 5, characterized in that, The command to increase ultrasonic energy includes a command to increase duty cycle and a command to increase transmission power; the command to decrease ultrasonic energy includes a command to decrease transmission power and a command to decrease duty cycle.
7. The downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system according to claim 6, characterized in that, Increasing duty cycle control commands have higher priority than increasing transmit power control commands; decreasing transmit power control commands have higher priority than decreasing duty cycle control commands.
8. The downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system according to claim 1, characterized in that, The downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system also includes a ground human-machine interface; the ground human-machine interface is connected to the ground control cabinet. The ground-based human-machine interface is used for: Obtain the preset target viscosity range, preset transmission power range, and preset duty cycle range; The system displays the real-time values of the viscosity measurement and ultrasonic emission parameters.
9. The downhole crude oil ultrasonic viscosity reduction closed-loop feedback control system according to claim 1, characterized in that, The controller incorporates a crude oil viscosity prediction model; this model is obtained by training a long short-term memory network. The controller is also used to obtain the viscosity prediction value for each time period in the future based on the viscosity measurement value at each time of the historical period using the crude oil viscosity prediction model. Based on the predicted viscosity values at each time point in the future, control commands for each time point in the future are generated in advance.
10. A closed-loop feedback control method for ultrasonic viscosity reduction of crude oil in downhole, implemented based on the closed-loop feedback control system for ultrasonic viscosity reduction of crude oil according to any one of claims 1-9, wherein the closed-loop feedback control method for ultrasonic viscosity reduction of crude oil in downhole comprises: Real-time acquisition of viscosity electrical signals of downhole crude oil within the working area of the ultrasonic transmitting sub; The viscosity electrical signal is amplified, filtered, and converted from analog to digital in real time to obtain the viscosity measurement value; Based on the measured viscosity value and the preset target viscosity range, control commands are generated; The ultrasonic emission parameters are adjusted according to the control command to reduce the viscosity of the downhole crude oil in the working area. The ultrasonic emission parameters include: emission power range and duty cycle.