A method for inverting the pump dynamometer card from the surface dynamometer card

Abstract

The present invention relates to the technical field of solving pump diagrams for oil pumping units, and in particular to a method for inverting a pump diagram from a surface diagram, comprising: obtaining basic data of an oil well and surface diagram data; determining key identification points based on the surface diagram; subtracting friction load data from the load data of the surface diagram, and eliminating vibration loads from the data after the friction load data is subtracted by filtering; subtracting inertia load data from the data after the vibration load data is eliminated to obtain a corrected surface diagram; subtracting the pump rod load from the load data in the corrected surface diagram, and subtracting the corresponding stroke loss from the displacement data, thereby inverting the pump diagram, and adjusting various parameters of the inverted pump diagram by comparing the inverted pump diagram with the actual measured pump diagram. The present invention solves the problem of large differences in pump diagram graphics due to the large number of damping coefficient parameters involved in calculating the damping coefficient and inaccurate damping coefficient calculation by inverting the pump diagram.

Description

Technical Field

[0001] The invention relates to the technical field of solving a pump diagram of an oil pumping unit, and in particular to a method for inverting a pump diagram from a surface diagram. Background Art

[0002] The pump performance diagram can accurately reflect the working condition of the sucker rod pump. When directly measuring the pump performance diagram, the dynamometer needs to be lowered into the well for measurement, which is a complex process and has high costs. Therefore, the method of converting the surface performance diagram into the pump performance diagram can accurately diagnose the working condition of the oil well, which is of great significance for strengthening oilfield management and improving the working performance of the sucker rod pump.

[0003] Chinese Patent Publication No. CN108661623A discloses a pump diagram calculation method and apparatus based on analysis of pumping unit suspension point load fluctuations, including the following steps: Step 1: Obtaining a longitudinal wave equation for the sucker rod; Step 2: Calculating the wave equation and obtaining an analytical solution to the wave equation; Step 3: Calculating the pump load based on the Fourier coefficients of the suspension point load; Step 4: Calculating the pump displacement based on the suspension point displacement and the Fourier coefficients of the pump load; Step 5: Calculating the pump diagram based on the suspension point indicator diagram; Step 6: Analyzing the fluctuation form under the action of the pump valve pulse load; and Step 7: Determining the sucker rod length l, damping coefficient v, and sucker rod cross-sectional area Ar based on the suspension point load fluctuation form. However, the shape of the pump diagram is largely affected by the damping coefficient. The damping coefficient formula is complex and involves many parameters, making it difficult to accurately calculate. This results in a significant discrepancy between the pump diagram and the actual pump diagram, seriously affecting the accuracy of subsequent operating condition diagnosis, production calculation based on the pump diagram, and dynamic liquid level calculation.

[0004] The existing technology has a problem that when calculating the damping coefficient, the damping coefficient is not calculated accurately because many damping coefficient parameters are involved, resulting in large differences in the pump power diagram graphics. Summary of the Invention

[0005] To this end, the present invention provides a method for inverting a pump power diagram from a ground power diagram, so as to overcome the problem in the prior art that when calculating the damping coefficient, a large number of damping coefficient parameters are involved, the damping coefficient calculation is inaccurate, and the graphics of the pump power diagram are greatly different.

[0006] To achieve the above object, the present invention provides a method for inverting a pump power diagram from a ground power diagram, comprising the following steps:

[0007] Obtain basic data of oil wells and ground performance map data;

[0008] Determine its identification key points based on the ground power map;

[0009] Subtracting friction load data from load data of the ground work diagram, and eliminating vibration loads by filtering the load data of the ground work diagram from which the friction load data has been subtracted;

[0010] Subtract the inertia load data from the load data of the ground work diagram after eliminating the vibration load data to obtain a corrected ground work diagram;

[0011] The pumping diagram is inverted by subtracting the rod load from the load data in the corrected surface diagram and subtracting the corresponding stroke loss from the displacement data.

[0012] By comparing the inverse pump performance diagram with the actual measured pump performance diagram, the parameters of the inverse pump performance diagram are adjusted.

[0013] Furthermore, the identification of key points is divided into two cases:

[0014] Under the condition of sufficient liquid supply, the key points include: floating valve closing point, fixed valve opening point, fixed valve closing point and floating valve opening point;

[0015] Under the condition of insufficient liquid supply, the key points include: floating valve closing point, fixed valve opening point, fixed valve closing point, friction turning point, liquid impact point and floating valve opening point.

[0016] Furthermore, there are two methods for eliminating friction load data from the ground work map data, including:

[0017] Determine the friction load between two points under the condition of sufficient fluid supply;

[0018] Determine the average friction load between two points under insufficient fluid supply conditions.

[0019] Furthermore, the ground power diagram is filtered by FFT Fourier transform to eliminate the influence of vibration, and the ground power diagram data after eliminating the friction load is used as the original signal data for Fourier transform to convert the ground power diagram data from the time domain to the frequency domain.

[0020] Furthermore, a spectrum is obtained according to the frequency domain analysis, and the spectrum is filtered through a low-pass filter to obtain a filtered spectrum, the spectrum is inverse Fourier transformed, the spectrum is converted back to the time domain, and filtered power diagram data is obtained again.

[0021] Furthermore, the method of reducing the inertial load from the ground power diagram after eliminating the influence of vibration is to calculate the suspension point acceleration according to the model of the beam pumping unit and the number of strokes, and to redefine the identification key points based on the power diagram after eliminating the vibration; based on the identification key points, calculate the average load of the upstroke and the average load of the downstroke

[0022] Furthermore, the inertia load of the upstroke is subtracted from the upstroke of the power diagram after vibration elimination, and the inertia load of the downstroke is subtracted from the downstroke, so as to obtain a corrected ground power diagram after inertia elimination.

[0023] Furthermore, the actual pump performance diagram is obtained by calculating the actual pump performance diagram, and the contour values of the actual pump performance diagram and the inverted pump performance diagram are compared; based on the contour value comparison result, the similarity between the inverted pump performance diagram and the actual pump performance diagram is determined.

[0024] Furthermore, the similarity is compared with a standard similarity of an actual pump performance diagram, and the difference level between the inverted pump performance diagram and the actual pump performance diagram is determined based on the comparison result.

[0025] Furthermore, based on the difference level, the inverted pump work diagram is adjusted with parameters corresponding to the difference level.

[0026] Compared with the prior art, the beneficial effect of the present invention lies in that, by acquiring basic data of the oil well and surface work diagram data, the present invention identifies key points based on the surface work diagram, subtracts friction load data from the load data of the surface work diagram, eliminates vibration loads through filtering of the load data of the surface work diagram after subtracting friction load data, subtracts inertia load data from the load data of the surface work diagram after eliminating vibration load data, and obtains a corrected surface work diagram, subtracts the sucker rod load from the load data in the corrected surface work diagram, subtracts the corresponding stroke loss from the displacement data, and then inverts the pump work diagram. The compliance rate of the pump work diagram solved by the method of this patent is greatly improved compared with that of solving the damping coefficient, and the accuracy of calculating the dynamic liquid level can also be improved by 5 percentage points.

[0027] Furthermore, the identification key points are divided into two situations, namely, under the condition of sufficient liquid supply and under the condition of insufficient liquid supply, so that different points can be selected for analysis in different situations, which effectively improves the accuracy of the method in inverting the pump work diagram.

[0028] Furthermore, the method of eliminating friction load data from ground work diagram data is divided into two cases, under sufficient fluid supply conditions and under sufficient fluid supply conditions, and can eliminate different load data under different conditions. The final inverted pump work diagram can better reflect the actual working conditions of the oilfield working pump.

[0029] Furthermore, the ground power diagram is filtered by FFT Fourier transform to eliminate the influence of vibration, which enables more accurate calculation of subsequent data and enables the inverted pump power diagram to more accurately reflect the actual working conditions.

[0030] Furthermore, by calculating the actual pump power diagram, the actual pump power diagram is obtained, and the contour values of the actual pump power diagram and the inverted pump power diagram are compared, so that the contour of the inverted pump power diagram can be judged and adjusted. If the contour of the inverted pump power diagram is equal to the contour of the actual pump power diagram, but the area is different, it is a first-level difference. By adjusting the absolute value of the difference between the area of the inverted pump power diagram and the area of the actual pump power diagram, the compensation parameter for the impact of the contour value of the actual pump power diagram is adjusted to avoid the impact of the difference between the area of the inverted pump power diagram and the actual pump power diagram on the accuracy of the inverted pump power diagram's response to the actual situation.

[0031] Furthermore, if the inverted pump performance diagram and the actual pump performance diagram have a secondary difference, it is necessary to adjust the X-axis adjustment value of the inverted pump performance diagram relative to the actual pump performance diagram in the coordinate system. After the adjustment value is adjusted, the inverted pump performance diagram can move left and right on the X-axis to approach the actual pump performance diagram so as to correctly reflect the actual situation of the pump operation in actual work.

[0032] Furthermore, if the inverted pump performance diagram and the actual pump performance diagram have a secondary difference, it is necessary to adjust the Y-axis adjustment value of the inverted pump performance diagram relative to the actual pump performance diagram in the coordinate system. After the adjustment value is adjusted, the inverted pump performance diagram can move up and down on the Y-axis to approach the actual pump performance diagram so as to correctly reflect the actual situation of the pump operation in actual work.

[0033] Furthermore, if the inverted pump performance diagram and the actual pump performance diagram have three levels of difference, it is necessary to compare the inverted pump performance diagram and the actual pump performance diagram in segments, and adjust the segmented inverted pump performance diagram by shrinking or enlarging it or adjust the X-axis and Y-axis related parameters in the coordinate system, and calibrate the final adjustment parameters. This allows for more detailed adjustments to be made to the inverted pump performance diagrams with different contours and areas to achieve a standard similarity to the actual pump performance diagram, and to more accurately reflect the real-time working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a flow chart of the method for inverting the pump power diagram from the surface power diagram of this embodiment;

[0035] Figure 2 The original surface performance diagram of the oil well used in the method of inverting the pump performance diagram from the surface performance diagram in Example 1;

[0036] Figure 3 The pump performance diagram of the oil well inverted by the method of inverting the pump performance diagram from the surface performance diagram in Example 1;

[0037] Figure 4 The original surface performance diagram of the oil well used in the method of inverting the pump performance diagram from the surface performance diagram in Example 2;

[0038] Figure 5 This is the pump performance diagram of the oil well inverted in the method of inverting the pump performance diagram from the surface performance diagram in the second embodiment. DETAILED DESCRIPTION

[0039] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are merely used to explain the present invention and are not intended to limit the present invention.

[0040] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0041] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside", and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and does not indicate or imply that the device or element 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.

[0042] Furthermore, it should be noted that, in the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0043] See also Figure 1-Figure 5 As shown, Figure 1 This is a flow chart of the method for inverting the pump power diagram from the surface power diagram of this embodiment; Figure 2 The original surface performance diagram of the oil well used in the method of inverting the pump performance diagram from the surface performance diagram in Example 1; Figure 3 The pump performance diagram of the oil well inverted by the method of inverting the pump performance diagram from the surface performance diagram in Example 1; Figure 4 The original surface performance diagram of the oil well used in the method of inverting the pump performance diagram from the surface performance diagram in Example 2; Figure 5 This is the pump performance diagram of the oil well inverted in the method of inverting the pump performance diagram from the surface performance diagram in the second embodiment.

[0044] This embodiment provides a method for inverting a pump power diagram from a surface power diagram, comprising the following steps:

[0045] Step S1, obtain the basic data of the oil well and the ground performance map data,

[0046] Step S2, determining the key points of recognition based on the ground power map;

[0047] Step S3, subtracting the friction load data from the load data of the ground work diagram, and filtering the load data of the ground work diagram from which the friction load data has been subtracted to eliminate the vibration load;

[0048] Step S4, subtracting the inertia load data from the load data of the ground work diagram after eliminating the vibration load data to obtain a corrected ground work diagram;

[0049] Step S5, subtracting the rod string load from the load data in the corrected surface work diagram, and subtracting the corresponding stroke loss from the displacement data, thereby inverting the pump work diagram;

[0050] Step S6: adjusting various parameters of the inverted pump performance diagram by comparing the inverted pump performance diagram with the actually measured pump performance diagram.

[0051] Specifically, the identification key points are divided into two cases:

[0052] Under the condition of sufficient liquid supply, the key points include: floating valve closing point, fixed valve opening point, fixed valve closing point and floating valve opening point.

[0053] Under the condition of insufficient liquid supply, the key points include: floating valve closing point, fixed valve opening point, fixed valve closing point, friction turning point, liquid impact point and floating valve opening point.

[0054] The identification key points are divided into two situations, under the condition of sufficient liquid supply and under the condition of insufficient liquid supply, and different points can be selected for analysis in different situations, which effectively improves the accuracy of the method for inverting the pump work diagram.

[0055] Specifically, there are two methods for eliminating friction load data from ground work map data, including:

[0056] Determine the friction load between two points under the condition of sufficient fluid supply;

[0057] In case of insufficient fluid supply,

[0058] Determine the load average F of all data points between the key points B and C BC ;

[0059] Determine the load average F of all data points between the key points C1 and D1 C1D1 ;

[0060] The method for eliminating friction load data from ground work diagram data is divided into two cases, under sufficient fluid supply conditions and under sufficient fluid supply conditions, and can eliminate different load data under different conditions. The final inverted pump work diagram can better reflect the actual working conditions of the oilfield working pump.

[0061] Specifically, there are two methods for eliminating friction load data from ground power map data:

[0062] Under the condition of sufficient fluid supply, the method of eliminating friction load includes the following steps:

[0063] Determine the friction load of adjacent equally spaced points between the floating valve closing point A and the fixed valve closing point C. The equally spaced points on the left and right of the floating valve closing point A are points A1 and A2, where A1=Ai and A2=A+i. The equally spaced points on the left and right of the fixed valve closing point C are points C1 and C2, where C1=Ci and C2=C+i, where i=1, 2, 3, 4, 5, 6, 7, 8.

[0064] The friction load at point A1 is FA1=F A-i , the friction load at point A2 is FA2=F A+i ,

[0065] The friction load at point C1 is FC1 = F C-i , the friction load at point A2 is FC2=F C+i , according to F A-i and F A+i , F C-i and F C+i , use formula (1) to determine the friction load F1 S ;

[0066]

[0067] Under the condition of insufficient fluid supply, the method of eliminating friction load includes the following steps:

[0068] Determine the load average F of all data points between the fixed valve opening point B and the fixed valve closing point C BC ;

[0069] Determine the load average F of all data points between the key friction turning point C1 and the liquid impact point D1 C1D1 ;

[0070] According to the F BC and F C1D1 , use formula (2) to determine the friction load F2 S ;

[0071]

[0072] Specifically, the ground power diagram is filtered by FFT Fourier transform to eliminate the influence of vibration, and the ground power diagram data after eliminating the friction load is used as the original signal data for Fourier transform to convert the ground power diagram data from the time domain to the frequency domain.

[0073] Specifically, a spectrum is obtained according to the frequency domain analysis, and the spectrum is filtered through a low-pass filter to obtain a filtered spectrum, the spectrum is inverse Fourier transformed, the spectrum is converted back to the time domain, and filtered power diagram data is obtained again.

[0074] Specifically, the method for reducing the inertial load from the ground power diagram after eliminating the influence of vibration is to calculate the suspension point acceleration according to the model of the walking beam pumping unit and the number of operating strokes, and to redefine the identification key points based on the power diagram after eliminating vibration; based on the identification key points, the average load of the upstroke and the average load of the downstroke are calculated.

[0075] Specifically, the inertia load of the upstroke is subtracted from the upstroke of the power diagram after vibration elimination, and the inertia load of the downstroke is subtracted from the downstroke to obtain a corrected ground power diagram after inertia elimination.

[0076] Specifically, based on the difference level, the inverted pump work diagram is adjusted with parameters corresponding to the difference level.

[0077] Specifically, after the ground power diagram eliminates the friction load, it needs to be filtered to eliminate the vibration effect. The method for eliminating vibration includes the following steps:

[0078] The FFT Fourier transform is used to filter and eliminate the influence of vibration.

[0079] Specifically, the method for reducing the inertial load after eliminating the influence of vibration includes the following steps:

[0080] According to the model of the beam pumping unit and the number of strokes n, calculate the suspension point acceleration a. A ;

[0081]

[0082] ω=60 / n (4)

[0083] Where a is the length of the front arm of the rocker beam, b is the length of the rear arm of the rocker beam, r is the crank radius, ω is the crank angular velocity, θ is the crank angle, and n is the number of strokes per minute. -1 ;

[0084] According to the work diagram after eliminating vibration, re-identify the key points; calculate the average load W of the upstroke 上 and the average load W during the downstroke 下 ;

[0085]

[0086] Where, the average load of the upstroke is W 上 is the average load of all data points between key points B and C, kN;

[0087] Average load of downstroke W 上 is the average load of all data points between key points A and D, kN;

[0088] Calculate the average upstroke load W 上 and the average load W during the downstroke 上 , using formula (7) (8), calculate the inertial load I of the upstroke respectively 上 and the inertial load I of the downstroke 下 ,

[0089]

[0090] Where g is the acceleration due to gravity, 9.8 m / s 2 ;

[0091] Subtract the inertia load I of the upstroke from the upstroke of the power diagram after vibration elimination 上 , downstroke minus the inertial load of the downstroke I 下 , and obtain the corrected ground work diagram after eliminating inertia.

[0092] The pump performance diagram is inverted by subtracting the rod string load from the load data in the corrected surface performance diagram and subtracting the corresponding stroke loss from the displacement data.

[0093] The formula for the sucker rod string load is:

[0094] W r =(1-ρ L / ρ r )q r L p (9)

[0095] Where q r is the weight of the sucker rod per meter in the air, Lp is the length of the sucker rod, ρL is the density of the liquid column in the wellbore, ρ r is the sucker rod density;

[0096] The formula for stroke loss is:

[0097] λ=W L L p (E r +E t ) (10)

[0098] Where W L is the liquid column load, L p is the sucker rod length E r is the elastic coefficient of the sucker rod, E t is the elastic coefficient of the tubing.

[0099] The specific steps of FFT Fourier transform filtering are:

[0100] The power diagram after eliminating the friction load is used as the original signal data for Fourier transformation, and the power diagram data is converted from the time domain to the frequency domain;

[0101] The spectrum obtained by analysis is filtered by a low-pass filter to obtain a filtered spectrum;

[0102] The filtered spectrum is inversely Fourier transformed, and the filtered spectrum is converted back to the time domain to obtain the filtered power diagram data again.

[0103] Specifically, the actual pump performance diagram is obtained by calculating the actual pump performance diagram, and the contour values of the actual pump performance diagram and the inverted pump performance diagram are compared; based on the contour value comparison result, the similarity between the inverted pump performance diagram and the actual pump performance diagram is determined.

[0104] Specifically, the similarity is compared with a standard similarity of the actual pump performance diagram, and the difference level between the inverted pump performance diagram and the actual pump performance diagram is determined based on the comparison result.

[0105] Specifically, the actual pump performance diagram is obtained through the actual mining process (although it is difficult to measure the actual pump performance diagram, in order to make a similarity judgment on the inverted pump performance diagram to adjust the corresponding parameters of the inverted pump performance diagram, the actual pump performance diagram is only measured in some areas for similarity verification). By comparing the contour similarity between the inverted pump performance diagram and the actual pump performance diagram, the pump performance diagram adjustment parameters are determined.

[0106] Taking the lower left inflection point of the pump work diagram as the coordinate origin, construct a coordinate system with displacement as the X-axis and load as the Y-axis.

[0107] Taking the coordinate origin as the starting point of the pump performance diagram, connect each inflection point in clockwise order to form a straight line, and calculate the slope of the straight line through the coordinates of each inflection point.

[0108] Set the coordinates of the first inflection point A1 with the starting point as (Xi1, Yi1), the coordinates of the second inflection point A2 as (Xi2, Yi2), the coordinates of the third inflection point A3 as (Xi3, Yi3), ..., the coordinates of the nth inflection point An as (Xin, Yin), where i = 1, 2, 3, ..., n,

[0109] The contour values of the inverted pump diagram and the actual pump diagram are determined by the area of the pump diagram and the slope of the straight lines forming each side of the pump diagram. The similarity of the inverted pump diagram is generated by comparing the contours of the inverted pump diagram and the actual pump diagram.

[0110] Pump power diagram contour value F=(K1+K2+K3+...+K n-1+Kn / n)×p+S×j, where K1 is the first slope from the starting point to the second inflection point (K1=(Yi2-Yi1) / (Xi2-Xi1), K2 is the second slope from the second inflection point to the third inflection point (K2=(Yi3-Yi2) / (Xi3-Xi2), and K3 is the third slope from the third inflection point to the fourth inflection point (K3=(Yi4-Yi3) / (Xi4-Xi3), ..., K n-1 is the n-1th slope K from the n-1th inflection point to the nth inflection point n-1 =(Yin-Yi n-1 ) / (Xin-Xi n-1 ), Kn is the nth slope from the nth inflection point to the n+1th inflection point Kn=(Yi n+1 -Yin) / (Xi n+1 -Xin), S is the pump work diagram area, j is the compensation parameter for the influence of the pump work diagram area on the pump work diagram contour value,

[0111] The contour value of the inverted pump performance diagram is Ff, the contour value of the actual pump performance diagram is Fs, and the standard similarity of the actual pump performance diagram is set to M.

[0112] If |Ff-Fs| / Fs≤M, the inverse pump work diagram does not require parameter adjustment;

[0113] If |Ff-Fs| / Fs>M, the parameters of the inversely derived pump diagram are adjusted.

[0114] For the inverted pump power diagram that does not meet the standard similarity, the overall contour deviation of the inverted pump power diagram is determined.

[0115] The priority of level difference adjustment is from large to small: three levels of difference, first level difference, second level difference,

[0116] If the similarity difference between the inverted pump power diagram and the actual pump power diagram is a first-order difference, where the area of the inverted pump power diagram and the actual pump power diagram are different under the same contour, then Fs = Ff × S' × Sa, where S' is the absolute value of the difference between the area of the inverted pump power diagram and the actual pump power diagram, and Sa is the compensation parameter for the impact of the absolute value of the difference between the area of the inverted pump power diagram and the actual pump power diagram on the contour value of the actual pump power diagram;

[0117] Assume that S1' is the absolute value of the first area difference between the inverse pump performance diagram and the actual pump performance diagram, and S2' is the absolute value of the second area difference between the inverse pump performance diagram and the actual pump performance diagram.

[0118] If S`≤S1`, then Sa=0.8;

[0119] If S1`<S`≤S2`, then Sa=1.1;

[0120] If S`>S2`, then S2`=1.2.

[0121] By calculating the actual pump power diagram, the actual pump power diagram is obtained, and the contour values of the actual pump power diagram and the inverted pump power diagram are compared, so that the contour of the inverted pump power diagram can be judged and adjusted. If the contour of the inverted pump power diagram is equal to the contour of the actual pump power diagram, but the area is different, it is a first-level difference. By adjusting the absolute value of the difference between the area of the inverted pump power diagram and the area of the actual pump power diagram, the compensation parameter affecting the contour value of the actual pump power diagram is adjusted to avoid affecting the accuracy of the inverted pump power diagram in responding to the actual situation due to the difference between the area of the inverted pump power diagram and the actual pump power diagram.

[0122] If the similarity difference between the inverted pump performance diagram and the actual pump performance diagram is a second-level difference, where the inverted pump performance diagram and the actual pump performance diagram have the same area under the same contour but different positions in the coordinate system, then the inverted pump performance diagram needs to be adjusted along the X-axis adjustment value Xa in the coordinate system relative to the actual pump performance diagram, and along the Y-axis adjustment value Ya in the coordinate system, Fs = Ff × (Xa × z1 + Ya × z2), where z1 is the compensation parameter for the influence of the inverted pump performance diagram on the X-axis adjustment value relative to the actual pump performance diagram, and z2 is the compensation parameter for the influence of the inverted pump performance diagram on the Y-axis adjustment value relative to the actual pump performance diagram;

[0123] Xa is positively correlated with z1, and Ya is positively correlated with z2.

[0124] Set the first standard adjustment value of the X axis to Xa1`, and the second standard adjustment value of the X axis to Xa2`

[0125] If Xa<Xa1`, then z1=0.7;

[0126] If Xa1`≤Xa≤Xa2`, then z1=0.9;

[0127] If Xa>Xa2`, then z1=1.1,

[0128] Set the first standard adjustment value of the Y axis to Ya1`, and the second standard adjustment value of the Y axis to Ya2`

[0129] If Ya<Ya1`, then z2=0.6;

[0130] If Ya1`≤Ya≤Ya2`, then z2=0.8;

[0131] If Ya>Ya2`, then z2=1.2.

[0132] If the inverted pump performance diagram and the actual pump performance diagram have a second-level difference, it is necessary to adjust the X-axis adjustment value of the inverted pump performance diagram relative to the actual pump performance diagram in the coordinate system. After the adjustment value is adjusted, the inverted pump performance diagram can be moved left and right on the X-axis to approach the actual pump performance diagram to correctly reflect the actual situation of the pump operation in actual work.

[0133] If the inverted pump performance diagram and the actual pump performance diagram have a secondary difference, it is necessary to adjust the Y-axis adjustment value of the inverted pump performance diagram relative to the actual pump performance diagram in the coordinate system. After the adjustment value is adjusted, the inverted pump performance diagram can move up and down on the Y-axis to approach the actual pump performance diagram to correctly reflect the actual situation of the pump operation in actual work.

[0134] If the similarity difference between the inverted pump power diagram and the actual pump power diagram is three-level difference, the three-level difference means that the inverted pump power diagram and the actual pump power diagram have different areas and similarities,

[0135] The inverted pump performance diagram and the actual pump performance diagram are divided into segments with equal intervals. The contour value of the first segment of the inverted pump performance diagram is Ff1, the contour value of the second segment of the inverted pump performance diagram is Ff2, the contour value of the third segment of the inverted pump performance diagram is Ff3, ..., the contour value of the mth segment of the inverted pump performance diagram is Ffm, m=1,2,3,...,n

[0136] The first segment contour value of the actual pump performance diagram is Fs1, the second segment contour value of the actual pump performance diagram is Fs2, the third segment contour value of the actual pump performance diagram is Fs3, ..., the mth segment contour value of the actual pump performance diagram is Fsm

[0137] Get the t-th segment contour value of any inverse pump performance diagram as Fft and compare it with the t-th segment contour value of the actual pump performance diagram as Fst, t=1,2,3,...,m,

[0138] Determine the difference between the inverse pump performance diagram segment t contour value Fft and the actual pump performance diagram segment t contour value Fst.

[0139] If the inverted pump performance diagram segment contour value Fft and the actual pump performance diagram segment contour value Fst are of the first order difference, then the inverted pump performance diagram segment contour value Fft is adjusted, that is, Fst = Fft × S't × Sat, where S't is the absolute value of the difference between the contour area of the inverted pump performance diagram segment t and the contour area of the actual pump performance diagram segment t, and Sa is the compensation parameter for the impact of the absolute value of the difference between the area of the inverted pump performance diagram segment t and the area of the actual pump performance diagram segment t on the contour value of the actual pump performance diagram segment t;

[0140] If the inverted pump performance diagram segment contour value Fft and the actual pump performance diagram segment contour value Fst are of secondary difference, then the inverted pump performance diagram segment contour value Fft is adjusted, that is, Fst = Fft×(Xat×z1+Yat×z2), wherein Xat is the adjustment value of the inverted pump performance diagram segment t along the X-axis in the coordinate system, and Yat is the adjustment value of the inverted pump performance diagram segment t along the Y-axis in the coordinate system.

[0141] The adjusted inverted pump performance diagram contour value is compared with the actual pump performance diagram contour value for similarity. If the adjusted similarity meets the standard similarity of the actual pump performance diagram, the adjusted inverted pump performance diagram is used as the standard pump performance diagram, and each difference level parameter is calibrated.

[0142] If the adjusted similarity does not meet the standard similarity of the actual pump performance diagram, the parameters of each difference level are further adjusted to achieve the standard similarity of the actual pump performance diagram.

[0143] If the inverted pump performance diagram and the actual pump performance diagram have three levels of difference, it is necessary to compare the inverted pump performance diagram and the actual pump performance diagram in sections, and adjust the segmented inverted pump performance diagram by shrinking or enlarging it, or adjust the X-axis and Y-axis related parameters in the coordinate system, and calibrate the final adjustment parameters. This allows for more detailed adjustments to be made to the inverted pump performance diagrams with different contours and areas to achieve a standard similarity to the actual pump performance diagram, and to more accurately reflect the real-time working conditions.

[0144] In this embodiment 1, the X1 oil well is an oil well with insufficient fluid supply, the pumping unit model is CYJY10-4.2-53HB, the pump hanging depth is 822.11 meters, the pump diameter is 57 mm, the outer diameter of the sucker rod is 22 mm, the length of the sucker rod is 803.32 meters, the inner diameter of the oil pipe is 62 mm, and the pumping time is 5 minutes. -1 , sucker rod density 7.85t / m 3 The density of the liquid column in the wellbore is 0.91 kg / m 3 , the elastic constant of the sucker rod is 1.2158×10 -5 (kN -1 ), the elastic constant of the tubing is 0.5751×10 -5 (kN -1 ).

[0145] In Example 2, the X2 oil well is a well with sufficient fluid supply, the pumping unit model is CYJY10-4.2-53HB, the pump hanging depth is 690.1 meters, the pump diameter is 57 mm, the sucker rod outer diameter is 22 mm, the sucker rod length is 670.85 meters, the oil pipe inner diameter is 62 mm, and the pumping time is 2.6 minutes. -1 , sucker rod density 7.85t / m 3 The density of the liquid column in the wellbore is 0.91 kg / m3 , the elastic constant of the sucker rod is 1.2158×10 -5 (kN -1 ), the elastic constant of the tubing is 0.5751×10 -5 (kN -1 ).

[0146] Specifically, the present invention obtains basic data of the oil well and surface work diagram data, identifies key points based on the surface work diagram, subtracts friction load data from the load data of the surface work diagram, eliminates vibration loads through filtering of the load data of the surface work diagram after subtracting friction load data, subtracts inertia load data from the load data of the surface work diagram after eliminating vibration load data, and obtains a corrected surface work diagram. The load data in the corrected surface work diagram is subtracted from the sucker rod string load, and the displacement data is subtracted from the corresponding stroke loss to invert the pump work diagram. The compliance rate of the pump work diagram solved by the method of this patent is greatly improved compared with that of solving the damping coefficient, and the accuracy of calculating the dynamic liquid level can also be improved by 5 percentage points.

[0147] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

[0148] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A method for inverting a pump power diagram from a ground power diagram, characterized in that: The following steps are involved: Obtain basic data of oil wells and ground performance map data; Determine its identification key points based on the ground power map; Subtracting friction load data from load data of the ground work diagram, and eliminating vibration loads by filtering the load data of the ground work diagram from which the friction load data has been subtracted; Subtract the inertia load data from the load data of the ground work diagram after eliminating the vibration load data to obtain a corrected ground work diagram; The pumping diagram is inverted by subtracting the rod load from the load data in the corrected surface diagram and subtracting the corresponding stroke loss from the displacement data. By comparing the inverse pump performance diagram with the actual measured pump performance diagram, the parameters of the inverse pump performance diagram are adjusted.

2. The method for inverting pump power diagram from ground power diagram according to claim 1, characterized in that: The identification key points are divided into two cases: Under the condition of sufficient liquid supply, the key points include: floating valve closing point, fixed valve opening point, fixed valve closing point and floating valve opening point; Under the condition of insufficient liquid supply, the key points include: floating valve closing point, fixed valve opening point, fixed valve closing point, friction turning point, liquid impact point and floating valve opening point.

3. The method for inverting pump power diagram from ground power diagram according to claim 1, characterized in that: There are two methods for eliminating friction load data from ground power map data, including: Determine the friction load between two points under the condition of sufficient fluid supply; Determine the average friction load between two points under insufficient fluid supply conditions.

4. The method for inverting pump power diagram from ground power diagram according to claim 1, characterized in that: The ground power diagram is filtered by FFT Fourier transform to eliminate the influence of vibration, and the ground power diagram data after eliminating the friction load is used as the original signal data for Fourier transform to convert the ground power diagram data from the time domain to the frequency domain.

5. The method for inverting pump power diagram from ground power diagram according to claim 4, characterized in that: A spectrum is obtained according to the frequency domain analysis, and the spectrum is filtered through a low-pass filter to obtain a filtered spectrum, and the spectrum is inverse Fourier transformed to convert the spectrum back to the time domain to obtain filtered power diagram data again.

6. The method for inverting pump power diagram from ground power diagram according to claim 5, characterized in that: The method for reducing the inertial load from the ground power diagram after eliminating the influence of vibration is to calculate the suspension point acceleration according to the beam pumping unit model and the number of running strokes, and redetermine the identification key points based on the power diagram after eliminating the vibration; Based on the identified key points, the average upstroke load and the average downstroke load are calculated.

7. The method for inverting pump power diagram from ground power diagram according to claim 6, characterized in that: The inertia load of the upstroke is subtracted from the upstroke of the power diagram after vibration elimination, and the inertia load of the downstroke is subtracted from the downstroke to obtain the corrected ground power diagram after inertia elimination.

8. The method for inverting pump power diagram from ground power diagram according to claim 6, characterized in that: The actual pump performance diagram is obtained by calculating the actual pump performance diagram, and the contour values of the actual pump performance diagram and the inverse pump performance diagram are compared; based on the contour value comparison result, the similarity between the inverse pump performance diagram and the actual pump performance diagram is determined.

9. The method for inverting pump power diagram from ground power diagram according to claim 8, characterized in that: The similarity is compared with a standard similarity of an actual pump performance diagram, and the difference level between the inverted pump performance diagram and the actual pump performance diagram is determined based on the comparison result.

10. The method for inverting pump power diagram from ground power diagram according to claim 9, characterized in that: Based on the difference level, the inverted pump work diagram is adjusted with parameters corresponding to the difference level.

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