Method and system for optimizing downhole fluid production
원문보기
IPC분류정보
국가/구분
United States(US) Patent
등록
국제특허분류(IPC7판)
G06F-017/50
E21B-043/12
F04B-047/02
F04B-049/06
G05B-013/04
출원번호
US-0757622
(2013-02-01)
등록번호
US-9033676
(2015-05-19)
발명자
/ 주소
Palka, Krzysztof
Czyz, Jaroslaw A.
출원인 / 주소
Pumpwell Solutions Ltd.
대리인 / 주소
Klarquist Sparkman, LLP
인용정보
피인용 횟수 :
1인용 특허 :
106
초록▼
A method and system for pumping unit with an elastic rod system is applied to maximize fluid production. The maximum stroke of the pump and the shortest cycle time are calculated based on all static and dynamic properties of downhole and surface components without a limitation to angular speed of th
A method and system for pumping unit with an elastic rod system is applied to maximize fluid production. The maximum stroke of the pump and the shortest cycle time are calculated based on all static and dynamic properties of downhole and surface components without a limitation to angular speed of the prime mover. Limitations of structural and fatigue strength are incorporated into the optimization calculation to ensure safe operation while maximizing pumped volume and minimizing energy consumption. Calculated optimal prime mover speed is applied to the sucker rod pump by means of beam pumping, long stroke or hydraulic pumping unit by controlling velocity, acceleration and torque of the electric prime mover or by controlling pressure and flow rate in hydraulically actuated sucker rod pumping system.
대표청구항▼
1. A method for controlling a prime mover speed in a pumping system for a well, the prime mover being operable at a variable instantaneous speed and controlled by a controller, the pumping system comprising a downhole pump and a connecting assembly comprising a rod string movable at a variable linea
1. A method for controlling a prime mover speed in a pumping system for a well, the prime mover being operable at a variable instantaneous speed and controlled by a controller, the pumping system comprising a downhole pump and a connecting assembly comprising a rod string movable at a variable linear velocity for operably connecting the prime mover and the downhole pump to provide reciprocal motive force to the downhole pump, the method comprising: varying an instantaneous speed of the prime mover by applying a set of optimal prime mover speed values previously generated for an entire stroke cycle to the controller, wherein the set of optimal prime mover speed values is generated for the entire stroke cycle to satisfy an optimization goal of maximizing a pumping system output production rate, subject to a set of constraints comprising: minimum and maximum stresses along the rod string over the entire stroke cycle;an allowable force or torque range of the prime mover; anda maximum prime mover speed,such that the instantaneous speed of the prime mover is substantially varied throughout the entire stroke cycle,wherein the set of optimal prime mover speed values was previously generated by a method comprising:representing prime mover speed values over the entire stroke cycle using a function Ω[p](x) comprising a mathematical formula defined with coefficient vector p comprising a finite number of coefficients [p1, p2, . . . , pm], and variable x, wherein x denotes either a time value or a stroke position within an interval (0, x0) of the stroke cycle, the stroke cycle comprising an upstroke and a downstroke movement of a polished rod comprised in the rod string; anddetermining the set of optimal values of p, such that the function Ω[p](x) satisfies the optimization goal and the set of constraints,wherein Ω[p](x) comprises a Fourier series, the coefficient vector p comprises Fourier coefficients, and Ω[p](x) is defined as: Ω[p](x)=βΩ_0[1+∑i=1N(γicos(2πⅈx/x0)+λisin(2πⅈx/x0))]wherein p comprises the Fourier coefficients [β, γ1, . . . , γN, λ1, . . . , λN] and Ω0 is an operating constant prime mover speed defined for the pumping system, and determining the set of optimal values of the coefficient vector p comprises:(i) selecting an initial vector p0 of the coefficient vector p, and m vectors Δpi, each vector comprising a prescribed incremental change Δpi of only one coefficient pi (i=1, . . . m);(ii) calculating, using the model, output values comprising a production rate V[p], a prime mover torque M[p](t) and a stress distribution of the rod string σ[p](z, t) varying with distance z along the length of the rod string and time t in the stroke cycle, the said output values calculated for the prime mover speed varying over the entire stroke cycle according to Ω[p] having a stroke period T[p] and determined at p=p0 and p=p0+Δpi (i=1, . . . m);(iii) calculating partial derivatives of the functions V[p], M[p](t), σ[p](z, t) and T[p] with respect to parameters pi (i=1, . . . m) using a finite difference method with the incremental values of the said functions calculated in step (ii) above;(iv) linearizing the functions V[p], M[p](t), σ[p](z, t) and T[p] by approximating the said functions at point p0 using a first order Taylor series expansion and the partial derivatives obtained in step (iii), the linearized functions having arguments consisting of small changes δpi of parameters p;(v) applying a linear programming method to find vector δp=[δp1, δp2, . . . , δpm,] that satisfies the optimization and the set of constraints;(vi) replacing the initial vector p0 with p0+δp and repeating steps (iii)-(v) until δp is smaller than a selected threshold;such that p is defined as p0 when δp is smaller than the selected threshold. 2. The method of claim 1, wherein the set of constraints further comprise at least one of: a maximum energy consumption of the prime mover;a maximum linear velocity of at least one point along the rod string; ora maximum output power of the prime mover. 3. The method of claim 2, wherein the set of constraints further comprises a prime mover speed at a beginning of the stroke cycle of the pumping system matching a prime mover speed at an end of the stroke cycle; and wherein the set of optimal prime mover speed values is generated once for a plurality of consecutive stroke cycles. 4. The method of claim 3, further comprising the step of generating the set of optimal prime mover speed values using a model representing components of the pumping system for predicting a response of the pumping system relative to the optimization goal and the set of constraints for a given instantaneous prime mover speed, said response comprising at least one of the following: pumping system output production rate;stresses along the rod string;a torque or force of the prime mover; orenergy consumption. 5. A method for controlling a prime mover speed in a pumping system for a well, the prime mover being operable at a variable instantaneous speed and controlled by a controller, the pumping system comprising a downhole pump and a connecting assembly comprising a rod string movable at a variable linear velocity for operably connecting the prime mover and the downhole pump to provide reciprocal motive force to the downhole pump, the method comprising: varying an instantaneous speed of the prime mover by applying a set of optimal prime mover speed values previously generated for an entire stroke cycle to the controller, wherein the set of optimal prime mover speed values is generated for the entire stroke cycle to satisfy an optimization goal of minimizing a pumping system energy consumption for a predefined output production rate, subject to a set of constraints comprising: minimum and maximum stresses along the rod string over the entire stroke cycle;an allowable force or torque range of the prime mover; anda maximum prime mover speed,such that the instantaneous speed of the prime mover is substantially varied throughout the entire stroke cycle,wherein the set of optimal prime mover speed values was previously generated by a method comprising:representing prime mover speed values over the entire stroke cycle using a function Ω[p](x) comprising a mathematical formula defined with coefficient vector p comprising a finite number of coefficients [p1, p2, . . . , pm], and variable x, wherein x denotes either a time value or a stroke position within an interval (0, x0) of the stroke cycle, the stroke cycle comprising an upstroke and a downstroke movement of a polished rod comprised in the rod string; anddetermining the set of optimal values of p, such that the function Ω[p](x) satisfies the optimization goal and the set of constraints,wherein Ω[p](x) comprises a Fourier series, the coefficient vector p comprises Fourier coefficients, and Ω[p](x) is defined as: Ω[p](x)=βΩ_0[1+∑i=1N(γicos(2πⅈx/x0)+λisin(2πⅈx/x0))]wherein p comprises the Fourier coefficients [β, γ1, . . . , γN, λ1, . . . , λN] and Ω0 is an operating constant prime mover speed defined for the pumping system, and determining the set of optimal values of the coefficient vector p comprises:(i) selecting an initial vector p0 of the coefficient vector p, and m vectors Δpi, each vector comprising a prescribed incremental change Δpi of only one coefficient pi (i=1, . . . m);(ii) calculating, using the model, output values comprising a production rate V[p], a prime mover torque M[p](t) and a stress distribution of the rod string σ[p](z, t) varying with distance z along the length of the rod string and time t in the stroke cycle, the said output values calculated for the prime mover speed varying over the entire stroke cycle according to Ω[p] having a stroke period T[p] and determined at p=p0 and p=p0+Δpi (i=1, . . . m);(iii) calculating partial derivatives of the functions V[p], M[p](t), σ[p](z, t) and T[p] with respect to parameters pi (i=1, . . . m) using a finite difference method with the incremental values of the said functions calculated in step (ii) above;(iv) linearizing the functions V[p], M[p](t), σ[p](z, t) and T[p] by approximating the said functions at point p0 using a first order Taylor series expansion and the partial derivatives obtained in step (iii), the linearized functions having arguments consisting of small changes δpi of parameters p;(v) applying a linear programming method to find vector δp=[δp1, δp2, . . . , δpm,] that satisfies the optimization and the set of constraints;(vi) replacing the initial vector p0 with p0+δp and repeating steps (iii)-(v) until δp is smaller than a selected threshold;such that p is defined as p0 when δp is smaller than the selected threshold. 6. The method of claim 5, wherein the set of constraints further comprise at least one of: a maximum linear velocity of at least one point along the rod string; ora maximum output power of the prime mover. 7. The method of claim 6, wherein the set of constraints further comprises a prime mover speed at a beginning of the stroke cycle of the pumping system matching a prime mover speed at an end of the stroke cycle; and wherein the set of optimal prime mover speed values is generated once for a plurality of consecutive stroke cycles. 8. The method of claim 7, further comprising the step of generating the set of optimal prime mover speed values using a model representing components of the pumping system for predicting a response of the pumping system relative to the optimization goal and the set of constraints for a given instantaneous prime mover speed, said response comprising at least one of the following: pumping system output production rate;stresses along the rod string;a torque or force of the prime mover; orenergy consumption. 9. A method for controlling a prime mover speed in a pumping system for a well, the prime mover being operable at a variable instantaneous speed and controlled by a controller, the pumping system comprising a downhole pump and connecting assembly comprising a rod string movable at a variable linear velocity for operably connecting the prime mover and the downhole pump to provide reciprocal motive force to the downhole pump, the method comprising: varying an instantaneous speed of the prime mover by applying a set of optimal prime mover speed values previously generated for an entire stroke cycle to the controller, wherein the set of optimal prime mover speed values is generated for the entire stroke cycle to satisfy an optimization goal of minimizing stresses along the rod string for a predefined output production rate, subject to a set of constraints comprising: an allowable force or torque range of the prime mover; anda maximum prime mover speed,such that the instantaneous speed of the prime mover is substantially varied throughout the entire stroke cycle,wherein the set of optimal prime mover speed values was previously generated by a method comprising:representing prime mover speed values over the entire stroke cycle using a function Ω[p](x) comprising a mathematical formula defined with coefficient vector p comprising a finite number of coefficients [p1, p2, . . . , pm] and variable x, wherein x denotes either a time value or a stroke position within an interval (0, x0) of the stroke cycle, the stroke cycle comprising an upstroke and a downstroke movement of a polished rod comprised in the rod string; anddetermining the set of optimal values of p, such that the function Ω[p](x) satisfies the optimization goal and the set of constraints,wherein Ω[p](x) comprises a Fourier series, the coefficient vector p comprises Fourier coefficients, and Ω[p](x) is defined as: Ω[p](x)=βΩ_0[1+∑i=1N(γicos(2πⅈx/x0)+λisin(2πⅈx/x0))]wherein p comprises the Fourier coefficients [β, γ1, . . . , γN, λ1, . . . , λN] and Ω0 is an operating constant prime mover speed defined for the pumping system, and determining the set of optimal values of the coefficient vector p comprises:(i) selecting an initial vector p0 of the coefficient vector p, and m vectors Δpi, each vector comprising a prescribed incremental change Δpi of only one coefficient pi (i=1, . . . m);(ii) calculating, using the model, output values comprising a production rate V[p], a prime mover torque M[p](t) and a stress distribution of the rod string σ[p](z, t) varying with distance z along the length of the rod string and time t in the stroke cycle, the said output values calculated for the prime mover speed varying over the entire stroke cycle according to Ω[p] having a stroke period T[p] and determined at p=p0 and p=p0+Δpi (i=1, . . . m);(iii) calculating partial derivatives of the functions V[p], M[p](t), σ[p](z, t) and T[p] with respect to parameters pi (i=1, . . . m) using a finite difference method with the incremental values of the said functions calculated in step (ii) above;(iv) linearizing the functions V[p], M[p](t), σ[p](z, t) and T[p] by approximating the said functions at point p0 using a first order Taylor series expansion and the partial derivatives obtained in step (iii), the linearized functions having arguments consisting of small changes δpi of parameters p;(v) applying a linear programming method to find vector δp=[δp1, δp2, . . . , δpm,] that satisfies the optimization and the set of constraints;(vi) replacing the initial vector p0 with p0+δp and repeating steps (iii)-(v) until δp is smaller than a selected threshold;such that p is defined as p0 when δp is smaller than the selected threshold. 10. The method of claim 9, wherein the set of constraints further comprise at least one of: a maximum energy consumption of the prime mover;a maximum linear velocity of at least one point along the rod string; ora maximum output power of the prime mover. 11. The method of claim 10, wherein the set of constraints further comprises a prime mover speed at a beginning of the stroke cycle of the pumping system matching a prime mover speed at an end of the stroke cycle; and wherein the set of optimal prime mover speed values is generated once for a plurality of consecutive stroke cycles. 12. The method of claim 11, further comprising the step of generating the set of optimal prime mover speed values using a model representing components of the pumping system for predicting a response of the pumping system relative to the optimization goal and the set of constraints for a given instantaneous prime mover speed, said response comprising at least one of the following: pumping system output production rate;stresses along the rod string;a torque or force of the prime mover; orenergy consumption. 13. The method of any one of claim 1, 5, or 9, wherein the generation of the set of optimal prime mover speed values further comprises calculating corresponding values of Ω[p](x) over an entire stroke cycle for a set of either predetermined time instances or predetermined stroke positions, using the set of optimal values of the coefficient vector p. 14. The method of any one of claim 1, 5, or 9, wherein the rod string comprises a polished rod, the generation of the set of optimal prime mover speed values comprises representing polished rod velocity values over the entire stroke cycle, and determining a set of optimal values for the polished rod velocity in satisfaction of the set of constraints. 15. The method of claim 14, wherein the rod string further comprises a sucker rod connected to the polished rod and to a plunger of the downhole pump, and at least a portion of the rod string operates inside a tubing filled with a fluid, and wherein the model further comprises at least one of: a force acting on the plunger determined from at least a hydrostatic pressure from a fluid surrounding the plunger;mechanical properties of the rod string;characteristics of interactions between the rod string, the tubing, and the fluid filling the tubing; orrod string displacements and velocities during the entire stroke cycle in response to a given polished rod movement. 16. The method of claim 14, wherein the connecting assembly further comprises a pumpjack and the model further comprises the prime mover force or torque being determined from at least one of: a force in the polished rod;inertial properties and distribution of masses in the pumpjack;inertial properties of the prime mover;inertial properties of a speed reduction mechanism in the pumpjack; oran acceleration of the prime mover. 17. The method of any one of claim 1, 5, or 9, wherein the set of optimal prime mover speed values is provided as a set of predetermined time values and corresponding optimal prime mover speed values, and varying the instantaneous speed of the prime mover further comprises applying the corresponding optimal prime mover speed value to the controller at each said time value within the stroke cycle. 18. The method of any one of claim 1, 5, or 9, wherein the set of optimal prime mover speed values is provided as a set of predetermined stroke positions and corresponding optimal prime mover speed values, and varying the instantaneous speed of the prime mover further comprises applying the corresponding optimal prime mover speed value to the controller at each said stroke position within the stroke cycle. 19. The method of any one of claim 1, 5, or 9, wherein the stroke position comprises either a polished rod position or a position of another moving component equivalent to a position of the polished rod within the entire stroke cycle. 20. The method of any one of claim 1, 5, or 9, further comprising, after varying the instantaneous speed of the prime mover by applying the set of optimal prime mover speed values for the entire stroke cycle to the controller: measuring physical conditions of the pumping system during operation;adjusting parameters of the model of the pumping system based on a comparison of said model with the measured physical conditions;generating a new set of optimal prime mover speed values using the model of the pumping system with the adjusted parameters; andapplying the new set of optimal prime mover speed values to the controller. 21. The method of claim 20, wherein the physical conditions comprise a stroke position and at least one of: a polished rod load;the prime mover torque or force; orprime mover power usage. 22. The method of claim 21, wherein at least a portion of the rod string operates inside a tubing filled with a fluid and wherein the physical conditions further comprise at least one of: pressure in the tubing;pressure in a well casing; orthe output production rate. 23. Code stored on a non-transitory computer-readable medium which, when executed by at least one processor of a computing device, causes the computing device to carry out the method of any one of claim 1, 5, or 9.
연구과제 타임라인
LOADING...
LOADING...
LOADING...
LOADING...
LOADING...
이 특허에 인용된 특허 (106)
Wenholz Bruce (Glendale CA) Gault R. H. (Lubbock TX) Jones Kerry A. (Bakersfield CA), Air balance control for a pumping unit.
Norris Orley (Jay) ; Findley ; Sr. David S., Control apparatus and method for controlling the rate of liquid removal from a gas or oil well with a progressive cavity pump.
Beck Thomas ; Garnall Stephen J.,CAX ; Kahn David Seemab ; McGee Bruce C. W.,CAX ; Sallwasser Alan J. ; Stapleton ; II George T. ; Wassell Mark W., Downhole induction heating tool for enhanced oil recovery.
Stuebinger Lon A. ; McKinzie Howard L., Dual injection and lifting system using a rod driven progressive cavity pump and an electrical submersible progressive cavity pump.
McKinzie Howard L. ; Stuebinger Lon A. ; Berry Michael R., Dual injection and lifting system using a rod driven progressive cavity pump and an electrical submersible pump and associate a method.
Wolcott John H. (Racine WI) Sieger William L. (Franklin WI) Watson Alvin J. (Ardmore OK), Eddy current drive and motor control system for oil well pumping.
Adams ; Jr. Harold P. (Oil City PA) Hill David R. (Oil City PA) Richey Lee M. (Franklin PA) Maitland Andrew B. (Cranberry PA) Banton William E. (Derry NH) Taylor David C. (Slippery Rock PA), Level sensor.
McTamaney Louis S. (Cupertino CA) Delfino Allan B. (Sunnyvale CA) Bisbee Gary W. (The Woodlands TX), Method and apparatus for detecting problems in sucker-rod well pumps.
McTamaney Louis S. (Cupertino CA) Delfino Allan B. (Sunnyvale CA) Waltrip Delbert F. (San Jose CA) Kirkpatrick Thomas I. (San Jose CA), Method and apparatus for detecting well pump-off.
McCoy James N. (2210 Midwestern Pkwy. Wichita Falls TX 76308) West Jerry B. (Dallas TX) Podio Augusto L. (Austin TX), Method and apparatus for measuring pumping rod position and other aspects of a pumping system by use of an accelerometer.
McTamaney Louis S. (Cupertino CA) Delfino Allan B. (Sunnyvale CA) Bisbee Gary W. (Woodlands TX), Method and apparatus for recording and playback of dynagraphs for sucker-rod wells.
Boone James R. (510 B Ave. J. East Grand Prairie TX 75050) Best Larry D. (Rte. 3 ; Box 317 Springtown TX 76082) Brown Ronnie D. (6808 Shadydale North Richland Hills TX 76180), Method and apparatus for variable speed control of oil well pumping units.
Walker ; Sr. Frank J. (8340 NE. 2nd Ave. Miami FL 33138) Walker ; Jr. Frank J. (5711 S. Utica Ave. Tulsa OK 74105), Method and system for controlling a mechanical pump to monitor and optimize both reservoir and equipment performance.
Walker ; Sr. Frank J. (8340 Northeast 2nd Ave. Miami FL 33138) Walker ; Jr. Frank J. (5711 South Utica Ave. Tulsa OK 74105), Method and system for controlling a mechanical pump to monitor and optimize both reservoir and equipment performance.
Turner John M. (3860 N. Butler ; Apartment 3 Farmington NM 87401) Nethers Jan L. (P.O. Box 3521 Farmington NM 87499) Knight Robert M. (Box 2659 Santa Fe NM 87504), Method of monitoring and controlling a well pump apparatus.
Bramlett, Bobby R.; Dorado, Doneil M.; Gibbs, Sam Gavin; Nolen, Kenneth Bernard; Boyer, LeMoyne, Methods, apparatus and products useful in the operation of a sucker rod pump during the production of hydrocarbons.
Swamy Mahesh M. (Salt Lake City UT) Bisel Gerald R. (Sandy UT) Rossiter Steven L. (Salt Lake City UT), Passive harmonic filter system for variable frequency drives.
Westerman G. Wayne (Midland TX) Montgomery Richard C. (Midland TX) Pippin Gerald W. (Midland TX), Pump control responsive to voltage-current phase angle.
Streib Stephen F. (Novato CA), Ultrasensitive apparatus and method for detecting change in fluid flow conditions in a flowline of a producing oil well,.
Chandra Rangasami S. (Walnut Creek CA) Quen Stephen G. (Fremont CA) Eineichner Donald E. (San Jose CA) Lastra Jorge E. (San Jose CA), Well production control system.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.