Intelligent Operation Control Method and System for Pumping Units Based on Negative Work Time Proportion Recognition

Abstract

This invention relates to the field of oilfield engineering technology, and particularly to an intelligent operation control method and system for pumping units based on negative power time ratio identification. The control method includes setting the operating parameters of the drive motor, starting the pumping unit at a set high speed; reading the set values ​​or calculating the duration of each stroke, statistically analyzing the duration of zero or negative power values, and calculating the proportion of zero or negative power in the stroke time; continuously collecting the proportion of zero or negative power in each stroke time, and determining whether the change in the proportion of zero or negative power in the stroke time over time is less than a cavitation threshold. If cavitation is determined, a speed control phase begins, with the motor running at low speed; after running for a specified duration, the motor controller increases the motor speed to run at high speed again; this process is repeated. The control method provided by this invention automatically adjusts the pumping unit operating parameters in real time, optimizes the pumping unit's operating conditions, extends the pump inspection cycle, reduces energy consumption, and saves manual labor.

Description

Technical Field

[0001] This invention relates to the field of oil production engineering technology, and in particular to an intelligent operation control method for oil pumping units based on negative work time ratio identification. Background Technology

[0002] The operating conditions of a single pumping unit well are mainly determined based on the dynamometer card and the dynamic fluid level. When the dynamic fluid level is low, the pumping unit's filling rate decreases. If the operating parameters of the pumping unit are not adjusted in time, causing the pumping unit to operate under insufficient fluid supply conditions for a long time, liquid hammer will occur, reducing the pumping unit's efficiency, increasing rod and tubing vibration, accelerating rod and tubing wear, increasing energy consumption, and significantly shortening the pump inspection cycle.

[0003] Due to the large number and wide distribution of pumping wells, the field typically measures the dynamometer card and fluid level of each well monthly as a basis for parameter adjustment. As the oilfield enters the later stages of development, the injection and production schemes are frequently adjusted, and the fluid production of pumping wells changes accordingly. This results in a large number of pumping wells operating under conditions of supply and drainage imbalance and inefficient production. The workload of on-site staff in adjusting operating parameters is constantly increasing, and the problem of high management difficulty is becoming increasingly prominent.

[0004] Current intelligent operation control methods for oil pumping units generally rely on data acquisition and analysis from multiple sensors, such as load sensors, position sensors, and angle sensors, to achieve intelligent operation control. These methods require the installation of complex equipment, increasing costs, and also have limited durability and reliability in outdoor production environments. Summary of the Invention

[0005] (a) Technical problems to be solved

[0006] This invention provides an intelligent operation control method for oil pumping units based on negative work time ratio recognition, which overcomes the shortcomings of existing oil pumping unit operation control methods, such as the need to install complex equipment, high control costs, and limited durability and reliability in outdoor production environments.

[0007] (II) Technical Solution

[0008] To address the aforementioned problems, this invention provides, in one aspect, an intelligent operation control method for pumping units based on negative work time ratio identification, comprising:

[0009] Step 1001: Set the operating parameters of the drive motor, including the upper limit value of the motor operating speed and the lower limit value of the motor operating speed, wherein the upper limit value corresponds to the high speed value of the motor that makes the pumping unit displacement greater than the oil well production, and the lower limit value corresponds to the low speed value of the motor that makes the pumping unit displacement less than the oil well production.

[0010] Step 1002: The drive motor operates at the set high speed to run the pumping unit, and the motor controller records the start-up time t.st ;

[0011] Step 1003: The motor controller collects the motor's operating power at a constant frequency through sensors and generates sampling points; the duration of each stroke is obtained by reading the set value or by calculation.

[0012] Step 1004: Determine the collected power values ​​of the motor and count the duration when the power value is zero or negative.

[0013] Step 1005: Calculate the proportion of zero or negative power in the duration of each impulse, where k1 at the initial impulse is denoted as k. st ;

[0014] Step 1006: Continuously collect the proportion of time with zero or negative power in each stroke, and repeat steps 1004 to 1005.

[0015] Step 1007: Continuously determine the change in the proportion of zero or negative power in the stroke time over time, and ensure that the rate of change is less than the emptying threshold k'. em When an oil pump is deemed to be underfilled, the time is recorded as t. em The proportion of zero or negative power in the duration of each impulse is denoted as k. em ;k em When the pumping unit is not fully filled, the proportion of the zero or negative power time period to the total stroke duration.

[0016] Based on the obtained parameters, a lower liquid level threshold k is generated as a proportion of zero or negative work time. ll ;

[0017] Step 1008: Start the speed control phase, the drive motor runs at a low speed for a fixed duration t. ls ;

[0018] Step 1009: The motor controller increases the motor speed, driving the motor to run at a high speed.

[0019] Step 1010: Determine whether the current proportion of zero or negative power in the stroke time reaches the lower liquid level threshold k. ll If yes, return to step 1008; otherwise, end and continue high-speed operation.

[0020] Preferably, in step 1005, the average value of the proportion of the stroke time occupied by zero or negative power is calculated, and the formula for the average value is:

[0021] k n =N nn / N a

[0022] Where: k nN represents the proportion of zero or negative power in the nth stroke cycle. a N represents the number of sampling points within each time period of each stroke. nn This indicates the number of sampling points where the power value is zero or negative.

[0023] Preferably, in step 1007, the formula for calculating the rate of change of the proportion of zero or negative power usage time over time is:

[0024] k' n =|k n -k n-1 | / k n-1

[0025] Where k' n k represents the proportion of zero or negative power duration in the nth cycle. n Rate of change over time, k1,k2…k n-1 k n This indicates the proportion of zero or negative power in the duration of each stroke, calculated in step 1006.

[0026] The method for determining insufficient filling of the oil pump is as follows:

[0027] k' n <k’ em

[0028] Insufficient fill threshold k' of oil pump em : 0.2 (% / min).

[0029] Preferably, in step 1007, the lower liquid level threshold k is the proportion of zero or negative work time. ll The calculation formula is:

[0030] k ll =k em +(k st -k em ) / 20;

[0031] Wherein, the initial k1 is denoted as k st .

[0032] Preferably, in step 1008, the operation at a low speed for a fixed time t is... ls The formula for determining the duration is:

[0033] t ls =(t em -t st ) / 4;

[0034] Where: t st The drive motor operates at a set high speed to power the pumping unit, and the motor controller records the start-up time.

[0035] Preferably, k' n It is the average value calculated over M consecutive stroke cycles (M>4).

[0036] Preferably, when the proportion of zero or negative power in the pulse time is too small, or when there is no zero or negative power value because the electrical parameter acquisition device cannot identify negative power, a set non-zero value line is used to replace the zero value line for judgment.

[0037] Among them, the proportion of zero or negative power in the impulse time is too small: k n =N nn / N a k n A percentage less than 2% is considered too small.

[0038] The method involves subtracting a fixed value E from the power value at each sampling point, and then judging according to the aforementioned method.

[0039] Among them, the peak power of the pumping unit is P max When, E=P max ×20%.

[0040] On the other hand, the present invention also provides an intelligent operation control system for a pumping unit based on negative work time ratio recognition, including a pumping unit, a downhole pumping pump, a drive motor, a sensor for collecting electrical parameters, and a motor controller for controlling the operation of the drive motor.

[0041] The pumping unit is connected to the downhole pump. The pumping unit is driven by a drive motor, which is controlled by a sensor that collects electrical parameters and a motor controller that controls the operation of the drive motor. When the pumping unit is doing negative work, the power meter reads zero or a negative value.

[0042] The motor control sets the operating parameters of the drive motor, including the upper limit value and the lower limit value of the motor operating speed. The upper limit value corresponds to the high speed value of the motor that makes the pumping unit displacement greater than the oil well production, and the lower limit value corresponds to the low speed value of the motor that makes the pumping unit displacement less than the oil well production.

[0043] The drive motor collects its operating power at a constant frequency through sensors.

[0044] The motor controller obtains the duration of each stroke by reading setpoints or calculating; it judges the collected power values, counts the duration of zero or negative power values, and calculates the proportion of zero or negative power in the stroke time; it continuously calculates the rate of change of the proportion of zero or negative power over time, and the rate of change is less than the emptying threshold k. em When an oil pump is deemed to be underfilled, the time is recorded as t. em The proportion of zero or negative power in the duration of each impulse is denoted as k.em Based on the obtained parameters, a lower liquid level threshold k is generated as the proportion of zero or negative work time. ll ;

[0045] During the initial speed control phase, repeat the process: the drive motor runs at low speed for a fixed duration t. ls The motor controller increases the motor speed to run at high speed until it determines that the rate of change is less than the vacuum threshold k. em .

[0046] (III) Beneficial Effects

[0047] The intelligent operation control method and system for pumping units based on negative work time ratio identification provided by this invention has the following advantages:

[0048] (1) Identify the working status of the oil pump based on the characteristics of the oil pumping unit's electrical parameters, and automatically adjust the working parameters of the oil pumping unit in real time to reduce on-site workload and improve the timeliness of parameter adjustment.

[0049] (2) This invention does not rely on various additional ground sensors, but only on the characteristics of the pumping unit's electrical parameters as the basis for parameter adjustment, resulting in lower equipment costs, enhanced system durability, and improved system reliability.

[0050] (3) The present invention can identify the downhole fluid supply capacity based on the automatic periodic change of the stroke, so that the pumping unit can operate at the most reasonable stroke, which can save energy and reduce consumption, and extend the pumping unit well inspection cycle. Attached Figure Description

[0051] Figure 1 This is a flowchart of the intelligent operation control method for oil pumping units based on negative work time ratio identification according to the present invention.

[0052] Figure 2 This is a schematic diagram of the intelligent operation control system for oil pumping units based on negative work time ratio recognition according to the present invention.

[0053] In the diagram: 1-Pumping unit; 2-Downhole pump; 3-Drive motor; 4-Sensor; 5-Motor controller. Detailed Implementation

[0054] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0055] like Figure 1 As shown, this invention provides an intelligent operation control method for oil pumping units based on negative work time ratio identification, comprising:

[0056] Step 1001: Set the operating parameters of the drive motor, including the upper limit value of the motor operating speed and the lower limit value of the motor operating speed, wherein the upper limit value corresponds to the high speed value of the motor that makes the pumping unit displacement greater than the oil well production, and the lower limit value corresponds to the low speed value of the motor that makes the pumping unit displacement less than the oil well production.

[0057] Step 1002: The drive motor operates at the set high speed to run the pumping unit, and the motor controller records the start-up time t. st ;

[0058] Step 1003: The motor controller collects the motor's operating power at a constant frequency through sensors and generates sampling points; the duration of each stroke is obtained by reading the set value or by calculation.

[0059] Step 1004: Determine the collected power values ​​of the motor and count the duration when the power value is zero or negative.

[0060] Step 1005: Calculate the proportion of zero or negative power in the duration of each impulse, where k1 at the initial impulse is denoted as k. st ;

[0061] In step 1005, the average value of the proportion of the stroke time occupied by zero or negative power is calculated, and the formula for the average value is:

[0062] k n =N nn / N a

[0063] Where: k n N represents the proportion of zero or negative power in the nth stroke cycle. a N represents the number of sampling points within each time period of each stroke. nn This indicates the number of sampling points where the power value is zero or negative.

[0064] Step 1006: Continuously collect the proportion of time with zero or negative power in each stroke, and repeat steps 1004 to 1005.

[0065] Step 1007: Continuously determine the change in the proportion of zero or negative power in the stroke time over time, and ensure that the rate of change is less than the emptying threshold k'. em When an oil pump is deemed to be underfilled, the time is recorded as t. em The proportion of zero or negative power in the duration of each impulse is denoted as k. em ;k em When the pumping unit is not fully filled, the proportion of the zero or negative power time period to the total stroke duration.

[0066] Based on the obtained parameters, a lower liquid level threshold k is generated as a proportion of zero or negative work time.ll ;

[0067] In this step, step 1007, the formula for calculating the rate of change of the proportion of zero or negative power duration over time is:

[0068] k' n =|k n -k n-1 | / k n-1

[0069] Where k' n k represents the proportion of zero or negative power duration in the nth cycle. n Rate of change over time, k1,k2…k n-1 k n This indicates the proportion of zero or negative power in the duration of each stroke, calculated in step 1006.

[0070] The method for determining insufficient filling of the oil pump is as follows:

[0071] k' n <k’ em

[0072] Insufficient fill threshold k' of oil pump em : 0.2 (% / min).

[0073] Preferably, in step 1007, the lower liquid level threshold k is the proportion of zero or negative work time. ll The calculation formula is:

[0074] k ll =k em +(k st -k em ) / 20;

[0075] Wherein, the initial k1 is denoted as k st .

[0076] In addition, when judging the change in the proportion of zero or negative power in the stroke time over time, the rate of change is greater than the pumping threshold k. em If the motor speed is maintained, then the current motor speed will be maintained.

[0077] Step 1008: Start the speed control phase, the drive motor runs at a low speed for a fixed duration t. ls ;

[0078] In this step, the operation at a low speed for a fixed time t is described. ls The formula for determining the duration is:

[0079] t ls =(t em -t st ) / 4;

[0080] Where: t st The drive motor operates at a set high speed to power the pumping unit, and the motor controller records the start-up time.

[0081] k' n It is the average value calculated over M consecutive stroke cycles (M>4).

[0082] If the proportion of zero or negative power in the pulse time is too small, or if there is no zero or negative power value because the electrical parameter acquisition device cannot identify negative power, a set non-zero value line is used to replace the zero value line for judgment.

[0083] Among them, the proportion of zero or negative power in the impulse time is too small: k n =N nn / N a k n A percentage less than 2% is considered too small.

[0084] The method involves subtracting a fixed value E from the power value at each sampling point, and then judging according to the aforementioned method.

[0085] Among them, the peak power of the pumping unit is P max When, E=P max ×20%.

[0086] Step 1009: The motor controller increases the motor speed, driving the motor to run at a high speed.

[0087] Step 1010: Determine whether the current proportion of zero or negative power in the stroke time reaches the lower liquid level threshold k. ll If yes, return to step 1008; otherwise, end and continue high-speed operation.

[0088] The intelligent operation control method for oil pumping units based on negative work time ratio identification provided by this invention has the following advantages:

[0089] (1) Identify the working status of the oil pump based on the characteristics of the oil pumping unit's electrical parameters, and automatically adjust the working parameters of the oil pumping unit in real time to reduce on-site workload and improve the timeliness of parameter adjustment.

[0090] (2) This invention does not rely on various additional ground sensors, but only on the characteristics of the pumping unit's electrical parameters as the basis for parameter adjustment, resulting in lower equipment costs, enhanced system durability, and improved system reliability.

[0091] (3) The present invention can identify the downhole fluid supply capacity based on the automatic periodic change of the stroke, so that the pumping unit can operate at the most reasonable stroke, which can save energy and reduce consumption, and extend the pumping unit well inspection cycle.

[0092] In addition, the present invention provides an intelligent operation control system for a pumping unit based on negative work time ratio recognition, including a pumping unit 1, a downhole pumping pump 2, a drive motor 3, a sensor 4 for collecting electrical parameters, and a motor controller 5 for controlling the operation of the drive motor.

[0093] The pumping unit 1 is connected to the downhole pumping unit 2. The pumping unit is driven by a drive motor 3. The drive motor 3 is controlled by a sensor 4 that collects electrical parameters and a motor controller that controls the operation of the drive motor. When the pumping unit is doing negative work, the power meter reads zero or a negative value.

[0094] The motor control sets the operating parameters of the drive motor, including the upper limit value and the lower limit value of the motor operating speed. The upper limit value corresponds to the high speed value of the motor that makes the pumping unit displacement greater than the oil well production, and the lower limit value corresponds to the low speed value of the motor that makes the pumping unit displacement less than the oil well production.

[0095] The drive motor collects its operating power at a constant frequency through sensors.

[0096] The motor controller obtains the duration of each stroke by reading setpoints or calculating; it judges the collected power values, counts the duration of zero or negative power values, and calculates the proportion of zero or negative power in the stroke time; it continuously calculates the rate of change of the proportion of zero or negative power over time, and the rate of change is less than the emptying threshold k. em When an oil pump is deemed to be underfilled, the time is recorded as t. em The proportion of zero or negative power in the duration of each impulse is denoted as k. em Based on the obtained parameters, a lower liquid level threshold k is generated as the proportion of zero or negative work time. ll ;

[0097] During the initial speed control phase, repeat the process: the drive motor runs at low speed for a fixed duration t. ls The motor controller increases the motor speed to run at high speed until it determines that the rate of change is less than the vacuum threshold k. em .

[0098] The intelligent operation control system for oil pumping units based on negative work time ratio identification provided by this invention has the following advantages:

[0099] (1) Identify the working status of the oil pump based on the characteristics of the oil pumping unit's electrical parameters, and automatically adjust the working parameters of the oil pumping unit in real time to reduce on-site workload and improve the timeliness of parameter adjustment.

[0100] (2) This invention does not rely on various additional ground sensors, but only on the characteristics of the pumping unit's electrical parameters as the basis for parameter adjustment, resulting in lower equipment costs, enhanced system durability, and improved system reliability.

[0101] (3) The present invention can identify the downhole fluid supply capacity based on the automatic periodic change of the stroke, so that the pumping unit can operate at the most reasonable stroke, which can save energy and reduce consumption, and extend the pumping unit well inspection cycle.

[0102] The above embodiments are only used to illustrate the present invention and are not intended to limit the present invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also fall within the scope of the present invention, and the patent protection scope of the present invention should be defined by the claims.

Claims

1. A method for intelligent operation control of an oil pumping unit based on negative work time ratio identification, characterized in that, include: Step 1001: Set the operating parameters of the drive motor, including the upper limit value of the motor operating speed and the lower limit value of the motor operating speed, wherein the upper limit value corresponds to the high speed value of the motor that makes the pumping unit displacement greater than the oil well production, and the lower limit value corresponds to the low speed value of the motor that makes the pumping unit displacement less than the oil well production. Step 1002: The drive motor operates at the set high speed to run the pumping unit, and the motor controller records the start-up time t. st ; Step 1003: The motor controller collects the motor's operating power at a constant frequency through sensors and generates sampling points; the duration of each stroke is obtained by reading the set value or by calculation. Step 1004: Determine the collected power values ​​of the motor and count the duration when the power value is zero or negative. Step 1005: Calculate the proportion of zero or negative power in the pulse time, where k1 at the initial pulse is denoted as k. st ; Step 1006: Continuously collect the proportion of time with zero or negative power in each stroke, and repeat steps 1004 to 1005. Step 1007: Continuously determine the change in the proportion of zero or negative power in the stroke time over time, and ensure that the rate of change is less than the emptying threshold k. em When an oil pump is deemed to be underfilled, the time is recorded as t. em The proportion of zero or negative power in the duration of each impulse is denoted as k. em ;k em When the pumping unit is not fully filled, the proportion of the zero or negative power time period to the total stroke duration. Based on the obtained parameters, a lower liquid level threshold k is generated as a proportion of zero or negative work time. ll ; Step 1008: Start the speed control phase, the drive motor runs at a low speed for a fixed duration t. ls ; Step 1009: The motor controller increases the motor speed, driving the motor to run at a high speed. Step 1010: Determine whether the current proportion of zero or negative power in the stroke time reaches the lower liquid level threshold k. ll If yes, return to step 1008; otherwise, end and continue high-speed operation.

2. The intelligent operation control method for pumping units based on negative work time ratio identification according to claim 1, characterized in that: In step 1005, the average value of the proportion of the stroke time occupied by zero or negative power is calculated, and the formula for the average value is: k n =N nn / N a Where: k n N represents the proportion of zero or negative power in the nth stroke cycle. a N represents the number of sampling points within each time period of each stroke. nn This indicates the number of sampling points where the power value is zero or negative.

3. The intelligent operation control method for pumping units based on negative work time ratio identification according to claim 1, characterized in that: In step 1007, the formula for calculating the rate of change of the proportion of zero or negative power usage time over time is: k’ n =|k n -k n-1 | / k n-1 Where k' n k represents the proportion of zero or negative power duration in the nth cycle. n Rate of change over time, k1,k2…k n-1 k n This indicates the proportion of zero or negative power in the duration of each stroke, calculated in step 1006. The method for determining insufficient filling of the oil pump is as follows: k’ n <k’ em 。 4. The intelligent operation control method for pumping units based on negative work time ratio identification according to claim 3, characterized in that: In step 1007, the lower liquid level threshold k is determined by the proportion of zero or negative work time. ll The calculation formula is: k ll =k em +(k st -k em ) / 20; Wherein, the initial k1 is denoted as k st .

5. The intelligent operation control method for pumping units based on negative work time ratio identification according to claim 1, characterized in that: In step 1008, the process of running at a low speed for a fixed time t... ls The formula for determining the duration is: t ls =(t em -t st ) / 4; Where: t st The drive motor operates at a set high speed to power the pumping unit, and the motor controller records the start-up time.

6. The intelligent operation control method for pumping units based on negative work time ratio identification according to claim 1, characterized in that: k' n It is the average value calculated from M consecutive stroke cycles.

7. The intelligent operation control method for pumping units based on negative work time ratio identification according to claim 1, characterized in that: If the proportion of zero or negative power in the pulse time is too small, or if negative power cannot be identified and there is no zero or negative power value, a set non-zero value line is used to replace the zero value line for judgment. Among them, the proportion of zero or negative power in the impulse time is too small: k n =N nn / N a k n A percentage less than 2% is considered too small. The method involves subtracting a fixed value E from the power value at each sampling point, and then judging according to the aforementioned method. Among them, the peak power of the pumping unit is P max At that time, E=P max ×20%.

8. A smart operation control system for a pumping unit based on negative work time ratio identification, the system being used to implement the smart operation control method for a pumping unit based on negative work time ratio identification as described in any one of claims 1-7, characterized in that, The system includes an oil pumping unit, a downhole oil pump, a drive motor, sensors for collecting electrical parameters, and a motor controller for controlling the operation of the drive motor. The pumping unit is connected to the downhole pump. The pumping unit is driven by a drive motor, which is controlled by a sensor that collects electrical parameters and a motor controller that controls the operation of the drive motor. When the pumping unit is doing negative work, the power meter reads zero or a negative value. The motor control sets the operating parameters of the drive motor, including the upper limit value and the lower limit value of the motor operating speed. The upper limit value corresponds to the high speed value of the motor that makes the pumping unit displacement greater than the oil well production, and the lower limit value corresponds to the low speed value of the motor that makes the pumping unit displacement less than the oil well production. The drive motor collects its operating power at a constant frequency through sensors. The motor controller obtains the duration of each stroke by reading setpoints or calculating; it judges the collected power values, counts the duration of zero or negative power values, and calculates the proportion of zero or negative power in the stroke time; it continuously calculates the rate of change of the proportion of zero or negative power over time, and the rate of change is less than the emptying threshold k. em When an oil pump is deemed to be underfilled, the time is recorded as t. em The proportion of zero or negative power in the duration of each impulse is denoted as k. em Based on the obtained parameters, a lower liquid level threshold k is generated as the proportion of zero or negative work time. ll ; During the initial speed control phase, repeat the process: the drive motor runs at low speed for a fixed duration t. ls The motor controller increases the motor speed to run at high speed until it determines that the rate of change is less than the vacuum threshold k. em .

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