Adaptable sucker rod pump controller and system suitable for use with various well topologies
AssigneeRavdos Holdings Inc.
InventorThomas Matthew Mills
Life of this patent
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Abstract
An adaptable controller for use with, and a method of operating, a sucker rod pumping system that controls the operation of the system based, at least in part on the Coulomb forces imposed upon the system during use as a result of the interaction of the sucker rod assembly components and the well and on forces imposed on the system as a result of downhole turbulence resulting from the placement of rod guide elements on the sucker rod and/or when the outer diameter of a coupling is large relative to the inner diameter of the well in which the sucker rod operates.
Claims15
An adaptable controller for controlling a drive system operating a sucker rod pumping unit at different operating speeds, the sucker rod pumping unit comprising a sucker rod, the controller comprising:
- a. stored processor executable instructions;
- b. a programmed processor operating in response to the stored instruction;
- c. a timer for determining the time of events or received inputs;
- d. a first input for receiving a first input signal comprising rod position data corresponding to the surface position of the sucker rod pumping unit;
- e. a second input for receiving a second input signal comprising rod load data corresponding to the surface load experienced by the sucker rod pumping unit;
- f. an output for providing control signals to the drive system to cause the drive system to vary the operating speed of the sucker rod pumping unit;
- g. wherein the stored instructions are configured to cause the programmed processor to:
- i. sample the first input signal and the second input signal various times;
- and
- ii. synchronize the rod position data obtained by the sampling of the first input signal and the road load data obtained by sampling the second input signal to provide data reflecting the rod position and rod load at given times;
- and
- h. wherein the stored instructions are configured to cause the programmed processor to generate a dynamometer card in accordance with a wave equation that:
- utilizes a damping coefficient c;
- utilizes a rod on tubing drag force C′(x) determined by the processor that includes both a tension-independent component and a tension-dependent friction component;
- and
- utilizes a turbulence factor z;
- i. wherein the stored instructions are configured to cause the programmed processor to use the generated dynamometer card to provide a control signal to the controller output to cause the drive system to vary the operating speed of the sucker rod pumping unit.
An adaptable controller for controlling a drive system operating a sucker rod pumping unit at different operating speeds, the sucker rod pumping unit comprising a sucker rod, the controller comprising:
- a. a programmed processor operating off of stored instruction;
- b. a timer for determining the time of events or received inputs;
- c. a first input for receiving a first input signal comprising rod position data corresponding to the surface position of the sucker rod pumping unit;
- d. a second input for receiving a second input signal comprising rod load data corresponding to the surface load experienced by the sucker rod pumping unit;
- e. an output for providing control signals to the drive system to cause the drive system to vary the operating speed of the sucker rod pumping unit;
- f. wherein the stored instructions are configured to cause the programmed processor to:
- i. sample the first input signal and the second input signal various times;
- and
- ii. synchronize the rod position data obtained by the sampling of the first input signal and the road load data obtained by sampling the second input signal to provide data reflecting the rod position and rod load at given times;
- and
- g. wherein the stored instructions are configured to cause the programmed processor to generate a dynamometer card in accordance with the equation below:
- d
- 2
-
- u
-
- (
- x
- ,
- t
- )
- d
-
- t
- 2
- =
- v
- 2
-
- d
- 2
-
- u
-
- (
- x
- ,
- t
- )
- d
-
- x
- 2
- -
- c
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-
- d
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-
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- x
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- d
-
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- C
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- x
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- g
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- z
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- d
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- u
-
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- x
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- EQUATION
-
- 1
- wherein:
- “x” is the distance of a point on the sucker rod from a define point;
- “t” is time;
- “μ(x, t)” is the displacement of the sucker rod from a defined position at time t;
- “v” is the velocity of sound in the sucker rod material;
- “c′” is a damping coefficient;
- “C′(x)” represents the rod on tubing drag force and includes both a tension-independent component and a tension-dependent friction component;
- “g(x)” represents a rod weight component;
- and
- “z” is a turbulence factor;
- and
- h. wherein the storied instructions are configured to cause the programmed processor to utilize the generated dynamometer card to provide a control signal to the controller output to cause the drive system to vary the operating speed of the sucker rod pumping unit.
A method of operating a sucker rod pumping unit at different operating speeds, the sucker rod pumping unit comprising a sucker rod, the controller comprising:
- a. determining the surface rod position at various times;
- b. determining the rod load at various times;
- c. time synchronizing the determined rod position data with the determined road load data to provide data reflecting the rod position and rod load at given times;
- and
- d. generating a dynamometer card in accordance with the equation below:
- d
- 2
-
- u
-
- (
- x
- ,
- t
- )
- d
-
- t
- 2
- =
- v
- 2
-
- d
- 2
-
- u
-
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- x
- ,
- t
- )
- d
-
- x
- 2
- -
- c
- ′
-
- d
-
- u
-
- (
- x
- ,
- t
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- d
-
- t
- -
- C
- ′
- (
- x
- )
- +
- g
-
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- x
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- -
- z
-
- d
- 2
-
- u
-
- (
- x
- ,
- t
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- d
-
- t
- 2
- EQUATION
-
- 1
- wherein:
- “x” is the distance of a point on the sucker rod from a define point;
- “t” is time;
- u(x, t)” is the displacement of the sucker rod from a defined position at time t;
- “v” is the velocity of sound in the sucker rod material;
- “c′” is a damping coefficient;
- “C′(x)” represents the rod on tubing drag force and includes both a tension-independent component and a tension-dependent friction component;
- “g(x)” represents a rod weight component;
- and
- “z” is a turbulence factor;
- and
- e. utilizing the generated dynamometer card to provide a control signal to the controller output to cause the drive system to vary the operating speed of the sucker rod pumping unit.
Dependencies are inferred from the claim text.