Openness control system of underground intelligent flow control valve

Abstract

The invention discloses an underground intelligent flow control valve opening degree control system which comprises a power supply conditioning module used for converting power supply voltage provided by the ground into working voltage of a motor; the voltage detection module is electrically connected with the power supply conditioning module and is used for detecting power supply voltage; the motor driving module is electrically connected with the voltage detection module; when the power supply voltage detected by the voltage detection module is in a voltage interval set for opening the valve, the motor driving module receives a forward rotation instruction, and the motor drives the valve to be opened; when the power supply voltage detected by the voltage detection module is in a voltage interval set for closing the valve, the motor driving module receives a reverse rotation instruction, and the motor drives the valve to be closed; the current detection module is electrically connected with the motor driving module and is used for detecting the working current of the motor in real time and sending current information to the motor driving module; and the position detection module is electrically connected with the motor driving module. The control system is simple in structure, high in control precision and capable of meeting underground application requirements.

Description

Technical Field

[0001] The present specification relates to the technical field of stratified oil production, and in particular to a downhole intelligent flow control valve opening control system. Background Art

[0002] Most of the domestic oil fields are multi-layer reservoir structures, and the inter-layer structure is very different, so it is necessary to carry out stratified fine production, and downhole flow control is the core technology of stratified fine production. The current practice is to use a bridge-type concentric water distributor to inject water into each layer to achieve stratified flow control or adopt a stratified automatic water injection scheme, relying on the downhole automatic circulation switch controlled by a single-chip microcomputer to automatically open and close it according to the set program in the downhole, so as to achieve stratified fine water injection. There is also a stratified water blocking technology, which uses a ground pressure device to open and close the valve of any oil layer in the well, and realizes stratified oil production by finding water blocking. In addition, using an intelligent completion system, its flow control method is to use hydraulic or electric methods to control the downhole layer control valve to achieve precise control of the flow of each layer in the well. Therefore, the downhole flow automatic control valve is a key equipment for realizing downhole stratified production. Summary of the invention

[0003] In view of the deficiencies in the prior art, one purpose of this specification is to provide a downhole intelligent flow control valve opening control system with a simple structure and high control accuracy, which can meet downhole application requirements.

[0004] To achieve the above objectives, the embodiments of this specification provide a downhole intelligent flow control valve opening control system, including: A power conditioning module, used to convert the power supply voltage provided on the ground into the working voltage of the motor; the motor is the actuator motor of the downhole flow control valve; A voltage detection module electrically connected to the power conditioning module, for detecting the supply voltage; a motor drive module electrically connected to the voltage detection module; when the power supply voltage detected by the voltage detection module is within the voltage interval set for valve opening, the motor drive module receives a forward rotation instruction, and the motor drives the valve to open; when the power supply voltage detected by the voltage detection module is within the voltage interval set for valve closing, the motor drive module receives a reverse rotation instruction, and the motor drives the valve to close; A current detection module electrically connected to the motor drive module, used for detecting the working current of the motor in real time and sending the current information to the motor drive module; The position detection module electrically connected to the motor driving module is used to detect the real-time position of the motor in real time and send the position information to the motor driving module.

[0005] As a preferred embodiment, the power conditioning module includes a power conditioning circuit, which includes a primary power module, a secondary power module and a tertiary power module connected in sequence, the primary power module and the tertiary power module are used for voltage reduction, the secondary power module is used for voltage stabilization, and the voltage reduction ratios of the primary power module and the tertiary power module are 1 / 8 and 1 / 2 respectively.

[0006] As a preferred implementation, the voltage detection module includes a voltage detection circuit, the detection point of the voltage detection circuit is the output end of the primary power supply module; the voltage detection circuit uses a sampling resistor to divide the voltage, and then sends the collected voltage signal to the A / D converter after filtering.

[0007] As a preferred implementation, the motor drive module includes a drive chip, and the drive chip has an H-bridge drive circuit integrated therein; the drive chip can operate continuously under the conditions of an output current of 5A and a voltage of 28V, with a maximum operating voltage of 40V and an operating temperature range of -40°C to 125°C.

[0008] As a preferred implementation, the position detection module includes a switch type Hall sensor and a magnet, the magnet is adhered to the side of the motor shaft of the motor, and the switch type Hall sensor is fixedly mounted on the end face flange of the motor.

[0009] As a preferred embodiment, the downhole intelligent flow control valve opening control system further includes a main program module electrically connected to the power conditioning module, the voltage detection module, the motor drive module, the current detection module, and the position detection module, and the following steps are set in the main program module: System initialization; Configure and initialize external capture interrupt, ADC sampling and analog watchdog interrupt, DMA module, timer cycle interrupt and interrupt priority, and set motor operation parameters; The system enters a loop after a delay; the loop includes reading the ADC value of the power supply voltage detected by the voltage detection module to control the running direction of the motor.

[0010] As a preferred embodiment, the downhole intelligent flow control valve opening control system also includes a periodic interrupt program module electrically connected to the main program module; in the periodic interrupt program module, the value of the number of revolutions of the motor rotor is first read, the given position is compared with the current feedback position to form a position deviation, and then the position deviation data is adjusted by a fuzzy PID algorithm to obtain the duty cycle of the PWM wave, and finally the PWM circuit is controlled to output a PWM wave to drive the motor.

[0011] As a preferred implementation, the formula of the fuzzy PID algorithm is: Among them, is the deviation between the given position and the feedback position; is the output result of the fuzzy PID algorithm; are the proportional coefficient, integral coefficient and differential coefficient of the fuzzy PID algorithm; and T is the control period.

[0012] As a preferred implementation, the downhole intelligent flow control valve opening control system further includes a capture interrupt program module electrically connected to the main program module, and the position feedback of the motor is implemented through the capture interrupt program module.

[0013] As a preferred embodiment, the downhole intelligent flow control valve opening control system also includes an ADC interrupt program module electrically connected to the main program module, the detection mode of the ADC interrupt program module is configured as a multi-channel scanning mode, and the interrupt type is selected as an analog watchdog interrupt. Beneficial Effects

[0014] The downhole intelligent flow control valve opening control system provided in this embodiment can convert the power supply voltage provided on the ground into the working voltage of the actuator motor by setting a power conditioning module. By setting a voltage detection module and a motor drive module, when the power supply voltage detected by the voltage detection module is in the voltage interval set for valve opening, the motor drive module receives a forward rotation instruction, and the motor drives the valve to open; when the power supply voltage detected by the voltage detection module is in the voltage interval set for valve closing, the motor drive module receives a reverse rotation instruction, and the motor drives the valve to close; during the operation of the motor, the current detection module and the position detection module will detect the working current and real-time position of the motor in real time, and send the current information and position information to the motor drive module to realize the precise position control of the motor. When a stall occurs or reaches a predetermined position, the motor drive module will control the motor to stop. The downhole intelligent flow control valve opening control system has a simple structure and high control accuracy, can meet the downhole application requirements, and can realize precise and intelligent control of the opening of the downhole flow control valve.

[0015] With reference to the following description and the accompanying drawings, the specific embodiments of the present invention are disclosed in detail, indicating the manner in which the principles of the present invention can be adopted. It should be understood that the embodiments of the present invention are not limited in scope thereby.

[0016] Features described and / or illustrated with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, combined with features in other embodiments, or substituted for features in other embodiments.

[0017] It should be emphasized that the term “include / comprises” when used herein refers to the presence of features, integers, steps or components, but does not exclude the presence or addition of one or more other features, integers, steps or components. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative labor.

[0019] Figure 1 This is a schematic diagram of the structure of a downhole intelligent flow control valve opening control system provided in this embodiment; Figure 2 A schematic diagram of a power conversion process of a power conditioning circuit provided in this embodiment; Figure 3 A schematic diagram of the structure of a control strategy provided in this embodiment; Figure 4 A program flow chart of a main program module provided in this embodiment; Figure 5 This is a program flow chart of a periodic interrupt program module provided in this embodiment.

[0020] Description of reference numerals: 1. Power conditioning module; 2. Voltage detection module; 3. Motor drive module; 4. Current detection module; 5. Position detection module; 10. Hardware part; 11. Power conditioning circuit; 111. Primary power module; 112. Secondary power module; 113. Third-stage power module; 12. Voltage detection circuit; 13. Motor drive and current detection circuit; 14. Position detection circuit; 20. Software part; 21. Main program module; 22. Periodic interrupt program module; 23. Capture interrupt program module; 24. ADC interrupt program module. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0022] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be another element centered thereon. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be another element centered thereon at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0024] See also Figures 1 to 5 The embodiment of the present application provides a downhole intelligent flow control valve opening control system, including a power conditioning module 1 , a voltage detection module 2 , a motor drive module 3 , a current detection module 4 and a position detection module 5 .

[0025] Among them, the downhole intelligent flow control valve opening control system preferably uses a high-performance, low-cost STM32 series chip (such as an STM32F103CBT7 chip) as a core controller (i.e., a main control unit) and adopts the above-mentioned modular design.

[0026] Specifically, the power conditioning module 1 is used to convert the power supply voltage provided by the ground into the working voltage of the motor. The motor is an actuator motor of the downhole flow control valve, preferably a DC motor. The motor, as an actuator, drives the valve mechanism to reach a predetermined opening position, thereby realizing the opening control of the downhole flow control valve. The working voltage of the motor is preferably 24V.

[0027] The voltage detection module 2 is electrically connected to the power conditioning module 1 and is used to detect the supply voltage. The motor drive module 3 is electrically connected to the voltage detection module 2. When the supply voltage detected by the voltage detection module 2 is in the voltage interval set for valve opening, the motor drive module 3 receives a forward rotation instruction, and the motor drives the valve to open; when the supply voltage detected by the voltage detection module 2 is in the voltage interval set for valve closing, the motor drive module 3 receives a reverse rotation instruction, and the motor drives the valve to close; when the supply voltage detected by the voltage detection module 2 is in other ranges, the motor drive module 3 will not make any response.

[0028] The current detection module 4 is electrically connected to the motor drive module 3, and is used to detect the working current of the motor in real time, and send the current information to the motor drive module 3. The position detection module 5 is electrically connected to the motor drive module 3, and is used to detect the real-time position of the motor in real time, and send the position information to the motor drive module 3.

[0029] The downhole intelligent flow control valve opening control system provided in this embodiment has a simple structure and high control accuracy, can meet downhole application requirements, and can achieve precise intelligent control of the opening of the downhole flow control valve.

[0030] Specifically, the ground setting system can be used to first write the parameters such as the opening position of the downhole flow control valve and the current of the motor stalling into the single-chip microcomputer (the single-chip microcomputer in this embodiment refers to the STM32F103CBT7 chip) in the RS232 protocol. When the downhole flow control valve needs to be opened, the ground staff only needs to set the voltage parameters of the switching power supply and transmit the high-voltage direct current to the downhole working layer section of several thousand meters through the power supply cable. At this time, the downhole voltage detection module 2 starts to detect the power supply voltage. When the voltage is in the voltage interval set for the valve opening, the single-chip microcomputer transmits the forward command to the motor drive module 3, and the motor will drive the valve mechanism to open; when the detected power supply voltage is in the voltage interval set for the reverse, the single-chip microcomputer transmits the reverse command to the motor drive module 3, and the motor will reverse and drive the valve mechanism to close; if the detected voltage is in other ranges, the single-chip microcomputer will not make any response. During the operation of the motor, the current detection module 4 and the position detection module 5 will detect the working current and real-time position of the motor in real time, and send the current information and position information to the single-chip microcomputer to realize the precise position control of the motor. When a stall occurs or the predetermined position is reached, the microcontroller will control the motor to stop.

[0031] In this embodiment, if Figure 1 As shown, the downhole intelligent flow control valve opening control system includes a hardware part 10, a software part 20 and a control strategy. The hardware part 10 includes a power conditioning circuit 11, a voltage detection circuit 12, a motor drive and current detection circuit 13, and a position detection circuit 14. The software part 20 includes a main program module 21, a periodic interrupt program module 22, a capture interrupt program module 23 and an ADC interrupt program module 24. The control strategy is described in detail below.

[0032] Specifically, the power conditioning module 1 includes a power conditioning circuit 11, which needs to convert the voltage provided by the ground into the working voltage of the motor. Usually, the downhole flow valve is installed several thousand meters underground. If the power is supplied directly, the voltage attenuation on the power line will be very large, which makes it difficult to control the voltage of the downhole node and the power supply efficiency is low. Based on this situation, the power supply of the entire system adopts a high-voltage transmission and voltage reduction solution. Since the power supply voltage reaches several hundred volts, the voltage drop on the power line is small. When it reaches the downhole node, it is reduced and stabilized, which improves the power supply stability and efficiency.

[0033] like Figure 2 As shown, the power conditioning circuit 11 adopts a multi-stage power conversion module, including a primary power module 111, a secondary power module 112 and a tertiary power module 113 connected in sequence. The primary power module 111 and the tertiary power module 113 are used for voltage reduction, and the secondary power module 112 is used for voltage stabilization. The voltage reduction ratios of the primary power module 111 and the tertiary power module 113 are 1 / 8 and 1 / 2 respectively. The above power modules can be products of VICOR Company of the United States.

[0034] In this embodiment, the voltage detection module 2 includes a voltage detection circuit 12. Power supply voltage detection is the core link of the entire control system. The control system uses a single-chip microcomputer to identify the power supply voltage value on the ground, thereby controlling the motor to make corresponding actions to open and close the flow valve. The collected voltage signal needs to correctly reflect the power supply voltage provided by the ground. Based on the voltage conversion process of the system, the detection point is selected at the output end of the downhole power supply module 111. Since the voltage range that the single-chip microcomputer ADC can convert is limited, the voltage detection circuit 12 uses a sampling resistor to divide the voltage, and then sends the collected voltage signal to the A / D converter of the single-chip microcomputer after filtering.

[0035] In this embodiment, the motor drive module 3 includes a driver chip, and the driver chip has an H-bridge drive circuit integrated therein. The driver chip can use the MC33886 of Freescale Semiconductor. The driver chip can work continuously under the conditions of an output current of 5A and a voltage of 28V, with a maximum operating voltage of 40V and an operating temperature range of -40°C to 125°C. It has the characteristics of overcurrent protection, undervoltage shutdown and fault output, and is a safe and efficient DC motor driver chip. The current detection of the motor still adopts the sampling resistor method. Since the output voltage signal of the sampling circuit is generally small and has noise, a filtering and amplification circuit is added to the back end to improve the sampling accuracy. The signal amplification chip selected is MAX4091, and the amplified signal is sent to the A / D converter of the microcontroller to complete the acquisition.

[0036] In this embodiment, the motor performs rotational motion, and the essence of position detection is rotation angle detection. In applications with high precision requirements, high-resolution encoders are generally used as position detection elements. The DC motor position detection scheme in this system uses a switch-type Hall sensor and a magnet to measure the number of motor rotations. This scheme is not only simple and easy to implement, but also saves development costs. Therefore, the position detection module 5 includes a switch-type Hall sensor and a magnet. The magnet is pasted on the side of the motor shaft of the motor, so that the magnet rotates with the motor; the switch-type Hall sensor is fixedly mounted on the end face flange of the motor and is fixed. When the motor is working, the switch-type Hall sensor will output high and low level signals due to changes in the intensity of the magnetic field. The number of turns is detected by using a single-chip microcomputer to detect the number of high and low levels.

[0037] In this embodiment, if Figure 3 As shown in the figure, the control strategy is: the final task of the control system is to realize the opening control of the downhole flow control valve, that is, the microprocessor controls the actuator motor to drive the valve mechanism to move to the position quickly and accurately according to the set opening position. The control object of the system is a micro DC motor, and a position single closed-loop control scheme is adopted.

[0038] In this embodiment, the downhole intelligent flow control valve opening control system further includes a main program module 21 electrically connected to the power conditioning module 1, the voltage detection module 2, the motor drive module 3, the current detection module 4, and the position detection module 5. Figure 4 As shown, the following programs are set in the main program module 21: First, the system is initialized, and then the external capture interrupt, ADC sampling and analog watchdog interrupt, DMA module, timer cycle interrupt and interrupt priority are configured and initialized, and the relevant software parameters (including motor operation parameters) are set. Then the system enters the loop after the delay wait. Subsequently, the detection return value (ADC value) of the power supply voltage detected by the voltage detection module 2 is read to control the running direction of the motor. After the motor is running, the loop waits for the interrupt to occur. When the system is powered on, the voltage will have a short rising process, which will cause the voltage value detected by the control system to be unstable, and misjudgment may occur at this time. Therefore, a delay link is added after the corresponding initialization is completed, so as to ensure that the control system detects a stable and reliable voltage value. The actual delay parameters can be tested and calibrated at the application site.

[0039] like Figure 5As shown, the underground intelligent flow control valve opening control system also includes a periodic interruption program module 22 electrically connected to the main program module 21. The main flow control valve opening control algorithm program is completed in the periodic interruption program (that is, the main work of the control strategy adopted by this system is completed by the periodic interruption program module 22), including the detection of the motor position, the position loop fuzzy PID algorithm and PWM generation. In the periodic interruption program module 22, the value of the number of revolutions of the motor rotor Count is first read, the given position is compared with the current feedback position to form a position deviation, and then the position deviation data is adjusted by the fuzzy self-tuning control algorithm to obtain the duty cycle of the PWM wave, and finally the PWM circuit is controlled to output the PWM wave to drive the motor.

[0040] For the downhole flow control valve opening control system, the position adjustment module needs to have fast, non-overshoot response characteristics, and strong robustness and adaptability. When the position deviation is large, it needs to be tracked quickly, and when the deviation is small, precise positioning is required. Conventional PID control algorithms are overly dependent on the control object model, and have poor parameter robustness and adaptability. For the downhole flow control valve opening control system, the fixed parameter PID control algorithm cannot meet the control requirements. In order to achieve better control effects, a fuzzy PID control algorithm is adopted. The formula of the fuzzy PID algorithm is: Among them, is the deviation between the given position and the feedback position; is the output result of the fuzzy PID algorithm; is the proportional coefficient, integral coefficient and differential coefficient of the fuzzy PID algorithm; T is the control period. The core idea of ​​the fuzzy PID control algorithm is to perform fuzzy reasoning based on the deviation and the deviation change, and realize the online adjustment of the three coefficients in the control algorithm to achieve the optimal control purpose, so that the system has better dynamic and static characteristics.

[0041] In this embodiment, the downhole intelligent flow control valve opening control system also includes a capture interrupt program module 23 electrically connected to the main program module 21, and the position feedback of the motor is realized by the capture interrupt program module 23. When the system is powered on, the motor will rotate in the set direction corresponding to the power supply voltage. In the external capture function configuration of the single-chip microcomputer, the trigger mode selects the rising edge trigger. When the rising edge of the zero position signal is detected, the capture interrupt program is entered. In the interrupt program, the running direction of the motor is detected by software, and the real-time actual position of the motor can be updated and the current actual position can be saved.

[0042] Specifically, the underground intelligent flow control valve opening control system also includes an ADC interrupt program module 24 electrically connected to the main program module 21. The entire control system needs to detect and collect two analog signals, one is the detection of the power supply voltage, and the other is the detection of the motor current, so the detection mode of the ADC interrupt program module 24 is configured to a multi-channel scanning mode. In order to quickly transmit and process data, the DMA function module of STM32 is turned on, and the conversion value of the ADC channel is stored in real time. At the same time, the interrupt of the ADC channel for motor current detection is turned on, and the interrupt type is selected as an analog watchdog interrupt. The watchdog interrupt threshold is set to the corresponding value of the maximum operating current allowed by the motor, and the motor is stopped in the interrupt service program. When the motor is blocked and overloaded during rotation, the analog watchdog interrupt will be triggered to achieve protection of the execution motor.

[0043] It should be noted that, in the description of this specification, unless otherwise specified, “plurality” means two or more.

[0044] Any numerical value cited herein includes all values ​​of lower and upper values ​​that increase by one unit from the lower limit to the upper limit, and there is at least a two-unit interval between any lower value and any higher value. For example, if the value of the quantity of a component or a process variable (such as temperature, pressure, time, etc.) is set forth to be from 1 to 90, preferably from 20 to 80, and more preferably from 30 to 70, the purpose is to illustrate that values ​​such as 15 to 85, 22 to 68, 43 to 51, 30 to 32 are also explicitly listed in the specification. For values ​​less than 1, one unit is appropriately considered to be 0.0001, 0.001, 0.01, 0.1. These are merely examples that are intended to be clearly expressed, and it can be considered that all possible combinations of numerical values ​​listed between the lowest value and the highest value are clearly set forth in the specification in a similar manner.

[0045] Unless otherwise indicated, all ranges include the endpoints and all numbers between the endpoints. "About" or "approximately" used with a range applies to both endpoints of the range. Thus, "about 20 to 30" is intended to cover "about 20 to about 30", including at least the specified endpoints.

[0046] All articles and references disclosed, including patent applications and publications, are incorporated herein by reference for all purposes. The term "consisting essentially of..." to describe a combination should include the identified elements, ingredients, parts or steps and other elements, ingredients, parts or steps that do not substantially affect the basic novel characteristics of the combination. The use of the terms "comprising" or "including" to describe a combination of elements, ingredients, parts or steps herein also contemplates embodiments that consist essentially of these elements, ingredients, parts or steps. By using the term "may", it is intended to indicate that any attribute described that "may" include is optional.

[0047] Multiple elements, ingredients, parts or steps can be provided by a single integrated element, ingredient, part or step. Alternatively, a single integrated element, ingredient, part or step can be divided into separate multiple elements, ingredients, parts or steps. The disclosure "one" or "an" used to describe an element, ingredient, part or step is not intended to exclude other elements, ingredients, parts or steps.

[0048] It should be understood that the above description is for illustration and not for limitation. Many embodiments and many applications beyond the examples provided will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of the present teachings should not be determined with reference to the above description, but should be determined with reference to the appended claims and the full scope of equivalents possessed by such claims. For the purpose of comprehensiveness, all articles and references, including disclosures of patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the preceding claims is not intended to be a waiver of the subject matter, nor should it be considered that the inventors did not consider the subject matter to be part of the disclosed inventive subject matter.

Claims

1. A downhole intelligent flow control valve opening control system, characterized in that: include: A power conditioning module, used to convert the power supply voltage provided on the ground into the working voltage of the motor; the motor is the actuator motor of the downhole flow control valve; A voltage detection module electrically connected to the power conditioning module, for detecting the supply voltage; a motor drive module electrically connected to the voltage detection module; when the power supply voltage detected by the voltage detection module is within the voltage interval set for valve opening, the motor drive module receives a forward rotation instruction, and the motor drives the valve to open; when the power supply voltage detected by the voltage detection module is within the voltage interval set for valve closing, the motor drive module receives a reverse rotation instruction, and the motor drives the valve to close; A current detection module electrically connected to the motor drive module, used for detecting the working current of the motor in real time and sending the current information to the motor drive module; The position detection module electrically connected to the motor driving module is used to detect the real-time position of the motor in real time and send the position information to the motor driving module.

2. The downhole intelligent flow control valve opening control system according to claim 1, characterized in that: The power conditioning module includes a power conditioning circuit, which includes a primary power module, a secondary power module and a tertiary power module connected in sequence. The primary power module and the tertiary power module are used for voltage reduction, and the secondary power module is used for voltage stabilization. The voltage reduction ratios of the primary power module and the tertiary power module are 1 / 8 and 1 / 2 respectively.

3. The downhole intelligent flow control valve opening control system according to claim 2, characterized in that: The voltage detection module includes a voltage detection circuit, and the detection point of the voltage detection circuit is the output end of the primary power supply module; the voltage detection circuit uses a sampling resistor to divide the voltage, and then sends the collected voltage signal to the A / D converter after filtering.

4. The downhole intelligent flow control valve opening control system according to claim 1, characterized in that: The motor drive module includes a drive chip, which has an H-bridge drive circuit integrated inside. The drive chip can work continuously under the conditions of an output current of 5A and a voltage of 28V, a maximum operating voltage of 40V, and an operating temperature range of -40°C to 125°C.

5. The downhole intelligent flow control valve opening control system according to claim 1, characterized in that: The position detection module includes a switch type Hall sensor and a magnet, wherein the magnet is adhered to the side of the motor shaft of the motor, and the switch type Hall sensor is fixedly mounted on the end face flange of the motor.

6. The downhole intelligent flow control valve opening control system according to claim 1, characterized in that: The downhole intelligent flow control valve opening control system further includes a main program module electrically connected to the power conditioning module, the voltage detection module, the motor drive module, the current detection module, and the position detection module. The following steps are set in the main program module: System initialization; Configure and initialize external capture interrupt, ADC sampling and analog watchdog interrupt, DMA module, timer cycle interrupt and interrupt priority, and set motor operation parameters; The system enters a loop after a delay; the loop includes reading the ADC value of the power supply voltage detected by the voltage detection module to control the running direction of the motor.

7. The downhole intelligent flow control valve opening control system according to claim 6, characterized in that: The downhole intelligent flow control valve opening control system also includes a periodic interrupt program module electrically connected to the main program module; in the periodic interrupt program module, the value of the number of revolutions of the motor rotor is first read, the given position is compared with the current feedback position to form a position deviation, and then the position deviation data is adjusted by a fuzzy PID algorithm to obtain the duty cycle of the PWM wave, and finally the PWM circuit is controlled to output a PWM wave to drive the motor.

8. The downhole intelligent flow control valve opening control system according to claim 7, characterized in that: The formula of the fuzzy PID algorithm is: Among them, is the deviation between the given position and the feedback position; is the output result of the fuzzy PID algorithm; are the proportional coefficient, integral coefficient and differential coefficient of the fuzzy PID algorithm; and T is the control period.

9. The downhole intelligent flow control valve opening control system according to claim 6, characterized in that: The downhole intelligent flow control valve opening control system further comprises a capture interrupt program module electrically connected to the main program module, and the position feedback of the motor is realized through the capture interrupt program module.

10. The downhole intelligent flow control valve opening control system according to claim 6, characterized in that: The downhole intelligent flow control valve opening control system also includes an ADC interrupt program module electrically connected to the main program module. The detection mode of the ADC interrupt program module is configured as a multi-channel scanning mode, and the interrupt type is selected as an analog watchdog interrupt.

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