Flexible control system of oil pumping unit

Abstract

The invention relates to the technical field of oil field oil production engineering, in particular to a flexible control system of a pumping unit. The flexible control system of the oil pumping unit comprises a data acquisition unit, a motor control unit, a signal transmission unit and a display control unit, and the data acquisition unit monitors operation parameters of a motor and the oil pumping unit in real time and transmits data to the motor control unit and the signal transmission unit. The motor control unit judges the tool state of the oil pumping unit according to the obtained data and adjusts the oil pumping unit, the signal transmission unit sends a signal to the display control unit for a worker to check, and the oil pumping unit can be controlled and adjusted to work through the display control unit. According to the flexible control system of the oil pumping unit, the working state of the oil pumping unit can be changed according to the change of the underground working condition, the working condition is automatically adjusted to the proper working condition, and abrasion of a sucker rod string is reduced; the working state of the oil pumping unit is remotely monitored and adjusted in real time through the display control unit, and the working efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of oil field production engineering, in particular to a flexible control system for an oil pumping unit. Background Art

[0002] In daily oilfield production, beam pumping units are a common piece of equipment. They primarily rely on a motor to drive the pumping rod in a uniform reciprocating motion to achieve production. As oilfield wells are exploited, the single uniform motion of existing beam pumping units has become inefficient in wells with frequent fluctuations in fluid production and variable operating conditions. The pumping rods are unable to adapt to changing well conditions, resulting in increased wear and tear and increased maintenance costs. Furthermore, remote monitoring and adjustment of the pumping units are impossible, and untimely adjustments to the units result in significant energy waste and an inability to meet production needs. To address these shortcomings, a flexible control system for pumping units has been proposed. Summary of the Invention

[0003] (1) Technical issues to be resolved

[0004] In response to the shortcomings of the existing technology, the present invention provides a flexible control system for oil pumping units, which solves the problems that the walking beam oil pumping unit always maintains a single uniform motion and cannot adapt to changes in oil well working conditions and cannot remotely monitor and adjust the oil pumping unit, resulting in serious energy waste.

[0005] (2) Technical solution

[0006] In order to solve the above problems, the present invention provides a flexible control system for an oil pumping unit, comprising:

[0007] A data acquisition unit, a motor control unit, a signal transmission unit and a display control unit, wherein the data acquisition unit monitors the operating parameters of the motor and the pumping unit in real time and transmits the data to the motor control unit and the signal transmission unit;

[0008] The motor control unit includes a data analysis module and a control module. The data analysis module is connected to the data acquisition unit and performs real-time analysis and calculation based on the operating parameters of the motor and the pumping unit to determine the operating status of the pumping unit and the motor and the operating condition of the oil well, and sends the calculation and judgment results to the control module. The control module is connected to the motor and controls the motor frequency to change according to the calculation and judgment results, so that it adapts to the current operating conditions and achieves flexible adjustment. The signal analysis module is also connected to the signal transmission unit and sends the calculation results to the signal transmission unit.

[0009] The display control unit is connected to the signal transmission unit, which transmits the received operating parameters and calculation results to the display control unit, which then displays the received data in the form of an image. The display control unit is provided with an input module connected to the control module, which allows control signals to be directly input to the controller unit to regulate the pumping unit motor.

[0010] Preferably, the data acquisition unit includes a motor parameter acquisition module and a pumping unit data acquisition module, which are respectively installed on the motor and the pumping unit and monitor their operating parameters in real time.

[0011] Preferably, the operating parameters monitored by the motor parameter acquisition module include motor current, voltage, frequency and torque signals; the operating parameters monitored by the pumping unit data acquisition module include the operating load, stroke and stroke frequency signals of the pumping unit.

[0012] Preferably, the control module controls the motor frequency to increase when the oil pumping unit has a high liquid production and is easy to exploit; and the control module controls the motor frequency to decrease when the oil pumping unit has a low liquid production and is difficult to exploit.

[0013] Preferably, the data processing module is based on the formula

[0014]

[0015] Calculate the dynamic liquid level L1;

[0016] Among them: A p is the cross-sectional area of ​​the plunger, mm 2 ;

[0017] A r is the cross-sectional area of ​​the rod, mm 2 ;

[0018] ρ is the liquid density, g / cm 3 ;

[0019] ρ t is the annular liquid density, g / cm 3 ;

[0020] H is the pump hanging height, m;

[0021] W r is the suspension point load, kN;

[0022] α is the acceleration factor, which is 1790;

[0023] And judge the working condition of the pumping unit according to the dynamic liquid level height L1.

[0024] Preferably, after receiving the signal from the data acquisition module, the data processing module will establish a real-time working diagram of the pumping unit according to the data, and calculate the liquid production according to the data on the working diagram. The calculation formula is Q=1440NA p S pe

[0025] N: represents the number of strokes, min -1 ;

[0026] A p : represents the cross-sectional area of ​​the plunger, m 2 ;

[0027] S pe : Indicates effective stroke, m;

[0028] And judge the output level based on the calculated output.

[0029] Preferably, a storage module is provided in the display control unit to store historical operation data and control signals.

[0030] Preferably, the display control unit is provided with an input module and is connected to the control module, and a control signal can be directly input to the controller unit through the input module to regulate the pumping unit motor.

[0031] Preferably, the display control unit includes a field terminal, a main control terminal and a mobile terminal which are independent of each other and have the same functions.

[0032] (3) Beneficial effects

[0033] The flexible control system of the oil pumping unit provided by the present invention can change the frequency of the oil pumping unit's motor according to changes in downhole working conditions through the cooperation of a data acquisition unit and a motor control unit, so that the working state of the walking beam oil pumping unit is automatically adjusted to a suitable working state as the downhole working conditions change, thereby reducing the wear of the sucker rod string and the cost of manual maintenance; through the cooperation of a signal transmission unit and a display control unit, the working state of the walking beam oil pumping unit can be remotely monitored and adjusted in real time, thereby improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a structural diagram of the flexible control system of the oil pumping unit of the present invention;

[0035] Figure 2 This is a working diagram of the flexible control system of the oil pumping unit of the present invention. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 making creative efforts are within the scope of protection of the present invention.

[0037] In the description of the present invention, it is necessary to understand that the orientations or positional relationships indicated by “upper”, “lower”, “inside”, “outside”, “top”, “bottom”, etc. are all based on the orientations or positional relationships shown in the accompanying drawings. The purpose is only to facilitate the description of the present invention and simplify the description. It does not indicate or imply that the referred parts must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0038] like Figure 1 As shown, the present invention provides a flexible control system for an oil pumping unit, which specifically includes: a data acquisition unit, a motor control unit, a signal transmission unit and a display control unit. The data acquisition unit performs trial detection on the operating status of the motor and the oil pumping unit and collects their real-time operating parameters and sends the collected operating parameters to the motor control unit and the signal transmission unit; the motor control unit judges the downhole working conditions according to the received operating parameters and controls the frequency change of the oil pumping unit according to the judgment result to adapt to the change of the downhole working conditions and realize automatic flexible control of the motor; the motor control unit sends the control signal and the judgment result to the signal transmission unit after controlling the motor action, and the signal transmission unit sends the real-time parameters of the motor and the oil pumping unit, the judgment result of the motor control unit and the control signal to the display control unit, and the display control unit displays the received signal and data to the staff, thereby realizing remote monitoring of the oil pumping unit and the motor.

[0039] Among them, the display control unit is provided with an input module. After the control signal is input to the display control unit through the input module, the display control unit sends the control signal directly to the motor control unit. The motor control unit controls the motor action according to the received control signal, thereby realizing remote control of the motor and the oil pumping unit, making it convenient to adjust the oil pumping unit and the motor in time when the oil pumping unit fails or the operating status is abnormal, thereby improving the safety of operation and production.

[0040] It should be noted that the data acquisition unit includes a motor parameter acquisition module and a pumping unit data acquisition module. The motor parameter acquisition module is installed on the pumping unit motor and monitors the motor's current, voltage, frequency, and torque signals in real time and sends them to the signal transmission unit; the pumping unit data acquisition module is installed on the pumping unit and monitors the pumping unit's operating load, stroke, and stroke frequency signals in real time and sends them to the signal transmission unit.

[0041] In the present invention, the motor control unit includes a data processing module and a control module. The data processing module is connected to the data acquisition unit to receive real-time data sent by the data acquisition unit and perform analysis, processing and real-time calculation on the received data, and judge the working conditions in the working well and the working state of the pumping unit according to the processing and calculation results, and send the processing, calculation results and judgment results to the control module; the control module controls the motor action to change the frequency of the motor according to the processing, calculation results and judgment results of the data processing module, thereby changing the working state of the pumping unit to adapt it to the working conditions in the well, realizing flexible automatic control of the pumping unit, reducing the degree of wear of the sucker rod column during operation, and reducing labor maintenance costs.

[0042] Among them, after performing data processing and calculation, the data processing module divides the downhole working conditions into high-production working conditions and low-production working conditions according to the results. Under the high-production working condition, the control module controls the motor to increase the frequency to speed up the strokes of the pumping unit and increase the pumping unit production; under the low-production working condition, the control module controls the motor frequency to reduce the strokes of the pumping unit, reduce energy waste and friction of the sucker rod string, reduce the workload of manual maintenance, and reduce maintenance costs and energy consumption costs.

[0043] The data processing module is based on the formula Calculate the dynamic liquid level L1,

[0044] Among them: A p is the cross-sectional area of ​​the plunger, mm 2 ; A r is the cross-sectional area of ​​the rod, mm 2 ;

[0045] ρ is the liquid density, g / cm 3 ρ t is the annular liquid density, g / cm 3 ;

[0046] H is the pump hanging height, m; W r is the suspension point load, kN;

[0047] α is the acceleration factor, which is 1790;

[0048] Among them A p 、A r ,ρ,ρ t and H can be measured before work is carried out, W r Through the real-time measurement of the pumping unit data acquisition module during the working process, W r The value of is different, so L1 will change according to the change of the pumping unit working condition.

[0049] Before formal operation begins, a measurement experiment is conducted on the target pumping unit. The L1 value ranges of the pumping unit under different operating conditions are measured and statistically analyzed to distinguish between easy-to-extract and difficult-to-extract conditions. The corresponding range values ​​are input into the data processing module. In actual operation, the real-time L1 value is calculated and the pumping unit operating condition is determined based on the range of L1. At the same time, according to actual work needs, the staff can further categorize the pumping unit's operating conditions into three, four, or even more states and determine the corresponding L1 value ranges.

[0050] like Figure 2 As shown, after receiving the data from the kitchenware collection unit, the data processing module will establish a real-time working diagram of the oil pumping unit based on the obtained data, and calculate the output of the oil pumping unit based on the data on the working diagram. The calculation formula is Q=1440NA p S pe

[0051] N: represents the number of strokes, min -1 ;

[0052] A p : represents the cross-sectional area of ​​the plunger, m 2 ;

[0053] S pe : Indicates effective stroke, m;

[0054] Before formal operation, the pumping unit's production needs to be divided into high-yield and low-yield intervals based on actual conditions, and the corresponding production value ranges must be determined. After the divided intervals and value ranges are input into the data processing module, the data processing module will make judgments based on the calculated production values ​​during operation. In actual operation, the production can be further refined into three or more intervals, and the corresponding values ​​and adjustment methods can be input into the motor control unit.

[0055] It should be noted that, in general, the control module is an STM32 single-chip microcomputer and the data processing and calculation process is realized by programming in the STM32. The internal microcontroller can be reprogrammed to adapt to actual production needs according to different situations.

[0056] like Figure 1As shown, the display control unit includes a mutually independent field terminal, a main control terminal, and a mobile terminal. The field terminal is generally installed in the form of a workbench at the pumping unit work site, facilitating observation of the pumping unit, motor, and downhole operating conditions during on-site work such as equipment maintenance and commissioning. The main control terminal is generally installed on the master controller of the control center, allowing staff to remotely monitor the operating conditions of each pumping unit and oil well in real time through the main control terminal. The mobile terminal is generally installed in the form of an app on mobile devices such as mobile phones and tablets and transmits information to the signal transmission unit and motor control unit via a wireless network. Through the coordination of the field terminal, the main control terminal, and the mobile terminal, staff can monitor the actual working conditions of the pumping unit and downhole in real time from anywhere, and can respond immediately when temporary adjustments are required or emergencies occur during the production process.

[0057] Among them, the display control unit is provided with an input module and is connected to the control module. The staff can directly input the control signal through the input module, and the display control unit sends the control signal to the control module to adjust the pumping unit motor.

[0058] It's important to note that the display control unit includes a storage module that can store historical data over a period of time and generate historical curves. During daily operations, personnel can access these historical data and curves by operating the display control unit. Comparing these historical curves with the work chart allows for online analysis of the well's production status. The Haas display control unit is connected to the on-site alarm system, so when a pumping unit safety failure occurs, an alarm message is sent to the display control unit to alert personnel.

[0059] The flexible control system for the pumping unit provided by the present invention can flexibly control the operating conditions of the pumping unit, allowing the working state of the beam pumping unit to automatically adjust to the appropriate working condition as the downhole working conditions change, thereby reducing wear on the pumping rod string and labor maintenance costs. The specific working process of the system is as follows:

[0060] Step 1: Install each module at the corresponding position of the target pumping unit according to the system structure.

[0061] Step 2: Conduct measurement experiments to determine the range of L1 values ​​of the pumping unit under different working conditions and the range of production values ​​under different production rates.

[0062] Step 3: Input the measurement results obtained in step 2 and the corresponding adjustment method into the motor control unit.

[0063] Step 4: The system and equipment are operated normally. The data acquisition unit monitors the pumping unit and motor in real time and sends the measured data to the data processing module.

[0064] In step 5, the data processing module determines the operating conditions and production based on the received data and adjusts the motor. During this process, the data processing module calculates the pumping unit's dynamic fluid level based on the data, generates a real-time operating diagram, and calculates real-time production based on the diagram. The module then determines the pumping unit's operating status based on the interval entered in step 3 and sends the results to the control module, which adjusts the motor's operating status according to a pre-determined adjustment method.

[0065] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A flexible control system for an oil pumping unit, characterized in that: include: A data acquisition unit, a motor control unit, a signal transmission unit and a display control unit, wherein the data acquisition unit monitors the operating parameters of the motor and the pumping unit in real time and transmits the data to the motor control unit and the signal transmission unit; The motor control unit includes a data analysis module and a control module. The data analysis module is connected to the data acquisition unit and performs real-time analysis and calculation based on the operating parameters of the motor and the pumping unit to determine the operating status of the pumping unit and the motor and the operating condition of the oil well, and sends the calculation and judgment results to the control module. The control module is connected to the motor and controls the motor frequency to change according to the calculation and judgment results, so that it adapts to the current operating conditions and achieves flexible adjustment. The signal analysis module is also connected to the signal transmission unit and sends the calculation results to the signal transmission unit. The display control unit is connected to the signal transmission unit, which transmits the received operating parameters and calculation results to the display control unit, which then displays the received data in the form of an image. The display control unit is provided with an input module connected to the control module, which allows control signals to be directly input to the controller unit to regulate the pumping unit motor.

2. The flexible control system for the oil pumping unit according to claim 1, characterized in that: The data acquisition unit includes a motor parameter acquisition module and a pumping unit data acquisition module. The motor parameter acquisition module and the pumping unit data acquisition module are respectively installed on the motor and the pumping unit and perform real-time monitoring of their operating parameters.

3. The flexible control system for the oil pumping unit according to claim 2, characterized in that: The operating parameters monitored by the motor parameter acquisition module include motor current, voltage, frequency and torque signal; the operating parameters monitored by the pumping unit data acquisition module include the operating load, stroke and stroke frequency signal of the pumping unit.

4. The flexible control system for the oil pumping unit according to claim 1, characterized in that: When the oil pumping unit has a high liquid production and is easy to exploit, the control module controls the motor frequency to increase; when the oil pumping unit has a low liquid production and is difficult to exploit, the control module controls the motor frequency to decrease.

5. The flexible control system for the oil pumping unit according to claim 4, characterized in that: The data processing module is based on the formula Calculate the dynamic liquid level L1, where: A p is the cross-sectional area of ​​the plunger, mm 2 ; A r is the cross-sectional area of ​​the rod, mm 2 ; ρ is the liquid density, g / cm 3 ; ρ t is the annular liquid density, g / cm 3 ; H is the pump hanging height, m; W r is the suspension point load, kN; α is the acceleration factor, which is 1790; And judge the working condition of the pumping unit according to the dynamic liquid level height L1.

6. The flexible control system for the oil pumping unit according to claim 5, characterized in that: After receiving the data from the data acquisition unit, the data processing module will establish a real-time working diagram of the pumping unit based on the data, and calculate the liquid production based on the data on the working diagram. The calculation formula is Q = 1440NA p S pe N: represents the number of strokes, min -1 ; A p : represents the cross-sectional area of ​​the plunger, m 2 ; S pe : Indicates effective stroke, m; And judge the output level based on the calculated output.

7. The flexible control system for the oil pumping unit according to claim 1, characterized in that: The display control unit is provided with a storage module for storing historical operation data and control signals.

8. The flexible control system for the oil pumping unit according to claim 1, characterized in that: The display control unit is provided with an input module and is connected to the control module. The control signal can be directly input to the controller unit through the input module to regulate the pumping unit motor.

9. The flexible control system for the oil pumping unit according to claim 6, characterized in that: The display control unit includes a field terminal, a main control terminal and a mobile terminal which are independent of each other and have the same functions.

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