WO2013106615A2 - Wellbore pressure actuation of downhole valves - Google Patents

Abstract

Methods and systems for operating a valve control system to control a valve in a wellbore include identifying a differential pressure arrangement of a plurality of differential pressure arrangements for actuating the valve to a desired state based on a differential pressure of at least two pressure sources of the wellbore and a present state of the valve. Once identified, the differential pressure arrangement of the at least two pressure sources are utilized to initiate actuation of the valve from the present state to the desired state.

Description

WELLBORE PRESSURE ACTUATION OF DOWNHOLE VALVES

€ r oss-Refer ence to Related Ap plica tions

[0001] This application claims priority to U.S. Provisional Application No.

61/586,486 filed January 13, 2012, the disclosure of which is incorporated by reference herein in its entirety.

Technical Field

[0002] Aspects of the disclosure are related to the field of subterranean fluid extraction, and in particular, wellbore pressure actuation of downhole valves.

Background

[0003] Weil systems are typically employed to access subterranean resources, such as water, petroleum, natural gas, or other fluids. A wellbore portion of the well system generally includes the hole (or holes) drilled from the surface to the desired subterranean depth, and also typically includes piping, annulus areas, and completion intervals for accessing the desired subterranean resources. Many modern wellbores incorporate several discrete pressure volumes separated by pressure barriers, such as packers. To facilitate transfer of the various fluids and materials to the surface, downhole valves, such as downhole flow control valves (DHFC), can be included in the wellbore. Typically, these downhole valves are hydraulicaily actuated and controlled by surface-based or seafloor-based wellhead systems.

[0004] For example, surface hydraulic systems can be employed to provide actuation pressure for downhole valves, where hydraulic fluid is delivered trom the wellhead down to the associated downhole valves via hydraulic lines or tubes which are separate from the main well piping. However, long hydraulic lines are required to be routed from wellhead hydraulic systems to the downhole valve systems, which can lead to static friction and valve actuation o vershoot problems, as well as overcrowding of the wellbore space from many hydraulic lines.

[0005] Hydraulic multiplexing systems have been devised which can share hydraulic lines among several downhole valves. However, these multiplexing systems typically employ hydraulic and electrical lines run from the wellhead to the downhole multiplexing system. Downhole batteries or electrical generation systems can be employed to reduce the quantity of electrical conductors run from the wellhead. However, even while reducing the quantity of hydraulic lines run from the wellhead to the downhole systems, these multiplexing systems still employ some long wellbore hydraulic lines which can suffer from the disadvantages discussed above, as well as maintenance and reliability problems associated with the multiplexing systems.

SUMMARY

[0006] Systems, devices, methods, and software for operating a wellbore valve control system are provided herein. In implementations, a method of operating a valve control system to control a valve in a wellbore is provided. The method includes identifying a differential pressure arrangement of a plurality of differential pressure arrangements for actuating the valve to a desired state based on a differential pressure of at least two pressure sources of the wellbore and a present state of the valve, and initiating actuation of the valve from the present state to the desired state using the differential pressure arrangement of the at least two pressure sources.

[0007] Additionally, in implementations, a method of operating a valve control system to control a valve in a wellbore is provided. The method includes monitoring pressure information associated with a. plurality of pressure regions of the wellbore, identifying a desired state of the valve, identifying actuation pressures among the plurality of pressure regions to actuate the valve to the desired state based on the pressure information and a present state of the valve, and applying the actuation pressures to the valve to actuate the valve to the desired state.

[0008] Additionally, in implementations, a valve control system to control a valve in a wellbore is provided. The valve control system includes a control interface configured to monitor pressure information associated with a plurality of pressure regions of the wellbore. The control interface is also configured to identify a desired state of the valve. The control interface is also configured to identify actuation pressures among the plurality of pressure regions to actuate the valve to the desired state based on the pressure information and a present state of the valve. The valve control system also includes an actuation system configured to apply the actuation pressures to the valve to actuate the valve to the desired state. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Various features of the implementations can be more fully appreciated, as the same become better understood with reference to the following detailed description of the implementations when considered in connection with the accompanying figures, in which:

[0010] Figure 1A is a system diagram illustrating a wellbore system, according to vari o us i mplemen tations .

[001 1 ] Figure IB is a system diagram illustrating a wellbore system, according to vari o us i mplemen tations .

[0012] Figure 2 is a flow diagram illustrating a method of operation of a valve control system, according to various implementations.

[0013] Figure 3 is a system diagram illustrating a valve control system, according to various implementations.

[0014] Figure 4 is a system diagram illustrating a valve control system, according to various implementations.

[00 j 5] Figure 5 is a system diagram illustrating a valve control system, according to various implementations.

[0016] Figure 6 is a flow diagram illustrating a method of operation of a valve control system, according to various implementations.

[0017] Figure 7 is a flow diagram illustrating a method of operation of a valve control system, according to various implementations.

[0018] Figure 8 is a system diagram illustrating a wellbore system, according to various implementations.

[0019] Figure 9 is a block diagram illustrating a valve control system, according to various implementations. DETAILED DESCRIPTION

[0020] For simplicity and illustrative purposes, the principles of the present teachings are described by referring mainly to examples of various implementations thereof. However, one of ordinary skill in the art would readily recognize that the same principles are equally applicable to, and can be implemented in, all types of information and systems, and that any such variations do not depart, from the true spirit and scope of the present teachings. Moreover, in the following detailed description, references are made to the accompanying figures, which illustrate specific examples of various implementations. Electrical, mechanical, logical and s tructural changes can be made to the examples of the various implementations without departing from the spirit and scope of the presen t teachings. The following detailed description is, therefore, not to be taken in a limiting sense and the scope of the present teachings is defined by the appended claims and their equivalents.

[0021 ] In the following discussion and in the claims, the terms "including" and "comprising" are used in an open-ended fashion, and thus should be interpreted to mean "including, but not limited to. . . ." Also, the term "couple" or "couples" is intended to mean either an indirect or direct connection. Thus, if a first device couples to a second device, that connection may be through a direct connection, or through an indirect connection via other devices, components, and connections. In addition, as used herein, the terms "axial" and "axially" generally mean along or parallel to a central axis (e.g., central axis of a body or a port), while the terms "radial" and "radially" generally mean peipendicular to the central axis. For instance, an axial distance refers to a distance measured along or parallel to the central axis, and a radial distance means a distance measured perpendicular to the central axis.

[0022] According to implementations, systems, methods, and software are directed to actuation of downhole valves using pressures found in these various fluid filled regions of a wellbore or associated completion intervals. In a well, there are typically several discrete regions separated by pressure barriers. For example, an upper annulus portion of a well can be separated from a lower completion by a production packer forming a pressure seal In a two-zone well, there are three discrete regions, such as the upper annulus, the upper completion interval, and the lower completion interval, in a three-zone well, there are four discrete regions, and likewise further zoned wells include 'η+Γ regions, and thus include 'n' number of downhole valves for controlling fluid flow and pressurization between the discrete regions. An open valve between two pressure regions will decrease the number of discrete pressure regions by one, due to the two pressure regions being connected through the open valve.

[0023] These downhole valves can include balanced piston driver-based valves, where a piston receives actuation from an applied differential pressure which subsequently actuates the connected valve mechanism. In these balanced piston driven valves, when fluid is forced into one end, the piston strokes the valve open, and likewise when fluid is forced into the other end, the piston strokes the valve closed. When a differential pressure across the piston is neutral or zero, then the valve remains as previously positioned. In

implementations, downhole valves can include ratcheting mechanisms to incrementally step an associated valve open or closed. The systems, methods, and software described herein can be applied to both balanced pistons and ratcheting pistons, among other piston/ alve configurations.

[0024] Figure 1A illustrates an example of wellbore system 100, according to various implementations. Figure IB includes a cross-sectional graphical representation of wellbore 101 of wellbore system 100, according to various implementations. While Figures 1 A and IB illustrate various components contained in the wellbore system 100, Figures 1A and IB illustrate one example of a wellbore system and additional components can be added and existing components can be removed. [0025] As illustrated in Figure 1A, wellbore system 100 includes valve control system 1 10, valve assembly 120, and two pressure sources, namely pressure sources 151 and 152. Valve control system 1 10 and valve assembly 120 are coupled over pressure lines 115 and 116. Valve assembly 120 includes valve 121 and piston 122.

[0026] As illustrated in Figure IB, wellbore 101 includes valve 121, pipe 161 , annulus 162, and pressure barrier 163. While only valve 121 of valve assembly 120 has been included in wellbore 101, wellbore 101 can include any components found in wellbore systems. Wellbore 101 represents a vertical wellbore, with pipe 161 surrounded by annulus 162, It should be understood that wellbore 101 is merely exemplary of a possible wellbore associated with system 100, and other wellbore representations and pressure co figurations can be employed.

[0027] In Figures 1A-1B, two wellbore pressure sources are included, namely first wellbore pressure source 151 (e.g. PI ) and second wellbore pressure source 152 (e.g. P2). These wellbore pressure sources can be associated with any two discrete pressure regions or volumes of a wellbore or wellbore system. For example, wellbore 101 shows P I as being a first pressure region 151 comprised of a completion interval below pressure barrier 163, and P2 as being a second pressure region 152 comprised of the annulus 162 above pressure barrier 163. It should be understood that these regions of wellbore 101 are generally cylindrical and surround associated portions of pipe 161.

[0028] The pressures associated with P I and P2 are coupled to valve control system 1 10 through pressure lines or tubes, as represented by the arrowed lines in system 100. Valve control system 110 can apply an arrangement of pressures PI and P2 to valve assembly 120 to actuate piston 122 according to a state of valve 121. The press ure arrangement is applied to valve assembly 120 by valve control system 1 10 over pressure lines 1 15 andl 16, which can comprise short hydraulic lines. It should be noted that pressure regions PI and P2 are not provided via pressure lines from wellhead or surface systems, such as hydraulic systems, and are instead provided from pressure regions of the wellbore itself.

[0029] As described herein, the state of the valve 121 can be referred to as a present state and a desired state. The present state indicated refers to a current position or current actuation state of a valve or valve assembly. The desired state indicated herein refers to a next position or next actuation state of a valve or valve assembly. For example, if a valve is presently in a closed state, the desired state will be a non-closed state, such as open or partially open. Likewise, if a valve is presently in an open state, the desired state will be a non-open state, such as closed or partially open.

[0030] The present state and desired state of valve 121 are also considered in identifying the differential pressure arrangement. For example, if a present state of valve 121 is a closed state, and the desired state is an open state, then a first differential pressure arrangement can be identified. Likewise, if the present state of a valve of valve assembly 120 is an open state, and the desired state is a closed state, then a second differential pressure arrangement can be identified.

[0031] In Figures 1A-1B, only two pressure regions are shown, namely P I and P2, so the differential pressure arrangement will be either a first arrangement or a second arrangement. However, more than two pressure regions can be included in other

implementations, and valve control system 1 10 can be configured to identify a differential pressure arrangement from among many differential pressure arrangements of the various wellbore pressure regions. For example, three pressure regions can be included in a wellbore, and valve control system 1 10 can identify a differential pressure arrangement from among at least six differential pressure arrangements of the three pressure regions. Thus, for 'n' number of pressure regions, there will be at least 'n! ' ('η' factorial) number of differential pressure arrangements to apply the pressures to the valve, where each pressure arrangement includes two pressure regions in a differential pressure arrangement.

[0032] Figure 2 illustrates an example of a method of operation of valve control system 1 10, according to various implementations. The illustrated stages of the method are examples and that any of the illustrated stages can be remo v ed, additional stages can be added, and the order of the illustrated stages can be changed.

[0033] As illustrated in Figure 2, in 201 , valve control system 1 10 can identify a differential pressure arrangement of a plurality of differential pressure arrangements for actuating valve 121 to a desired state based on differential pressure of at least two pressure sources of a wellbore and a present state of valve 121. The differential pressure arrangement includes an arrangement of at least two pressures associated with, the various discrete wellbore pressure regions, for example, P I and P2 as illustrated in Figures 1A-1B, The differential pressure arrangement identified is then used during actuation of valve assembly 120.

[0034] In 202, valve control system 110 can initiate actuation of valve 121 from a present state to a desired state using the differential pressure arrangement of the at least two pressure sources. Once the differential pressure arrangement has been identified, then valve control system 110 can initiate actuation of valve 121 of valve assembly 120, In

implementations, this initiation of the actuation can include instructing or controlling elements of valve control system 110 or valve a ssembly 120 to apply the pressures associated with the identified differential pressure arrangement to piston 122 which subsequently actuates valve 121 to the desired state. For example, PI can be instructed or commanded to be applied to a first end of piston 122 and P2 can be applied to a second end of piston 122. Piston 122 can then respond in accordance with the applied differential pressure and consequently actuate connected valve 121 to the desired state. [0035] Figures 3-5 illustrate example of valve control system 301 in wellbore system 300, according to various implementations, in implementations, valve control system 301 can be an example of valve control system 110 of Figures 1A and I B, although valve control system 110 can use other configurations. Various configurations of wellbore system 300 and valve control system 301 are shown in Figures 3-5, with details focused on the aspects of selectively applying various wellbore pressures across contamination barriers to a piston/valve assembly 350. The various elements and components of Figures 3-5 are merely representative of the various components employed, and different actual shapes, sizes, positions, and orientations can be employed. Likewise, while Figures 3-5 illustrate various components contained in the wellbore system 300, Figures 3-5 illustrate several examples and additional components can be added and existing components can be removed.

[0036] System 300 can include valve control system 301 and valve assembly 350. Valve control system 301 can include pressure monitors 31 1 and 312, isolation valves 315 and 316, crossover valves 320 and 340, contamination prevention elements 330 and 335, and control module 360. Valve assembly 350 can include piston 351, piping 352, valve 353, and fluid flow path 355 through piping 352. Pressure and fluid can be transferred or routed throughout valve control system 301 by assorted pressure tubing or piping, as indicated by the associated lines in Figures 3-5. Control, monitoring, and processing elements of valve control system 301 are shown in Figures 3-5 as a simplified control module 360 to emphasize the other elements. A discussion of the elements of Figures 3-5 are discussed below followed by various examples.

[0037] Two pressures can be applied to valve control system 301, namely PI and P2. For exemplary purposes, P I is shown to be of a greater pressure than P2 in Figures 3-5, although other configurations can be employ ed, including more than two pressure sources. Pressures P I and P2 are wellbore pressure regions, such as those discussed in connection with Figures 1A-1 B, and associated tubing and pressure regions are omitted from Figures 3-5 for clarity. Based on pressures PI and P2, valve control system 301 can selectively apply a differential pressure arrangement to valve assembly 350, which in turn opens or closes valve 353.

[0038] Pressure monitors 311 and 312 are included on each line between valve control system 301 and the associated pressure source to report pressure information for each pressure source, such as reporting a pressure in millibars, atmospheres (ATM), Pascals (Pa), Newtons per square meter (N/nr), pounds per square inch (psi), or other unit of

measurement, and can be provided in gauge or absolute pressures. Other information can also be provided, such as temperature, flow rate, or other information related to valve control system 301 or the wellbore pressure sources. Pressure monitors 311 and 312 can each include pressure transducers, pressure sensors, thermal monitoring components, or flow rate sensors, among other elements. Pressure monitors 311 and 312 can also each include communication systems and power systems for receiving power and commands as well as for communicating the various monitored information with monitoring and processing systems for operating valve control system 301 , such as with control module 360. Wired, wireless, or optical communication, signaling, or power links can be employed between pressure monitors 31 1 and 312 and above-ground control systems, such as control module 360,

[0039] Isolation valves 315 and 316 can be employed on the pressure lines associated with each pressure source to turn the associated pressure supply on or off.

Isolation valves 315 and 316 can also prevent undesired flow of fluid or pressure from any pressure region to another. Isolation valves 315 and 316 can be activated under the control of an operator system, and can include further actuation elements under the command and control of surface control elements. Isolation valves 315 can 316 can each include valves, actuators, electrical power elements, motors, and communication elements. In implementations, isolation valves 315 and 316 can share communication and power links with pressure monitors 31 1 and 312. Wired, wireless, or optical communication, signaling, or power links can be employed between isolation valves 315 and 316 and above-ground control systems, such as control module 360.

[0040] Crossover valves 320 and 340 can each selectively apply fluid or pressure sources in a first configuration or a second configuration based on a positional alignment of crossover valve elements. For example, crossover valve 320 can selectively apply pressure PI and P2 in either a first configuration or a second configuration to a first or 'dirty' side of contamination prevention elements 330 and 335. Likewise, crossover valve 340 can selectively apply pressures in either a first configuration or a second configuration from a second or 'clean' side of contamination prevention elements 330 and 335 to valve assembly 350. Although, a linear 'sliding' representation is shown in Figures 3-5, crossover valves 320 and 340 are merely shown schematically to indicate which pressure inputs are routed to which pressure outputs. Crossover valve 320 includes pressure routes 321 and 324, and crossover valve 340 includes pressure routes 341 and 344. Crossover valves 320 and 340 can each include valves, tubing, actuation motors, actuation pistons, as well as power and communication elements. Crossover valves 320 and 340 can each include sensors, such as position sensors, to monitor a. present actuation state and report the present actuation state to control module 360. Wired, wireless, or optical communication, signaling, or power links can be employed between crossover valves 320 and 340 and above-ground control systems. In Figures 3-5, each crossover valve has two arrangements for routing pressures, a 'straight' configuration noted by the straight routes 321, 322, 341, 342, and a 'crossover' configuration noted by the crossover routes 323, 324, 343, 344. If more than two pressure sources are employed, then further routes can be included in the crossover valves or further crossover valves can be employed to establish a multi-selection valve. [0041 ] Contamination prevention elements 330 and 335 can each provide an associated barrier 331 and 336 which allows for pressure transfer while preventing mixing of fluids across the barrier. Contamination prevention elements 330 and 335 can each include fluid containers or reservoirs, such as cylinders, with contamination barriers 331 and 336 each including bellows, pistons, or the like. Dirty or contaminated fluid can be shown as fluid 332 and 337, while clean fluid is shown as fluid 333 and 338. The fluid reservoirs can be sized to provide enough clean fluid for multiple actuations of valve assembly 350, A volume of several liters can be employed in implementations where valve assembly 350 uses a volume of approximately 0.5 liter to actuate. The shapes and sizes of the fluid reservoirs in Figures 3-6 can also merely representative and these can be narrowly shaped to fit in a downhole environment and are also not shown to scale. Contamination prevention elements 330 and 335 can each include sensors, such as position sensors for barriers 331 and 336, to monitor clean and dirty fluid levels in the cylinders of contamination prevention elements 330 and 335 and report the fluid levels to control module 360.

[0042] In implementations, valve assembly 350 can include hydraulic piston 351 and can typically use pristine or clean fluid to function properly over the lifetime of the well. In implementations, hydraulic fluid NAS 6 classification can be employed on the clean side of the contamination barrier for actuating valve assembly 350. Thus, the 'clean' side of valve control system 301 and valve assembly 350 can remain in a self-contained, clean, and sealed system. In contrast, the 'dirty' side of valve control system 301 , including crossover valve 320 and isolation valves 315-316, can be configured to tolerate fluids and materials associated with each of the pressure sources, such as petroleum, gas, water, solids, tracking chemicals, drilling mud, or other welibore fluids and materials. Entry of wellbore solids can be minimized on the dirty side of valve control system 301 through the use of screens, filters, sumps, shaped tubing, or the like.

1.) [0043] Valve assembly 350 can include elements of a downhole valve assembly, such as a downhole flow control valve (DHFC). In implementations, valve assembly 350 can include a cylinder portion to allow piston 351 to respond to pressure and fluid changes applied by crossover valve 340. Valve 353 can operate using an aperture-style opening which is either covered or not covered depending upon the position of piston 351. It should be understood that other valve configurations can be employed, and valve assembly 350 is merely shown to indicate an open or closed state based on a position of piston 351.

[0044] Valve assembly 350 can include balanced piston driver-based valves, where a piston receives actuation from an applied differential pressure which subsequently actuates the connected valve mechanism. In these balanced piston driven valves, when fluid is forced into one end, the piston can stroke the valve open, and likewise when fluid is forced into the other end, the piston can stroke the valve closed. When a differential pressure across the piston is neutral or zero, then the valve can remain as previously positioned. In

implementations, downhole valves can include ratcheting mechanisms to incrementally step an associated valve open or closed.

[0045] Control module 360 can include communication interfaces, signaling interfaces, digital processors, computer systems, microprocessors, circuitry, non-transient computer-readable media, user interfaces, or other processing devices or software systems, and can be distributed among multiple processing devices. Control module 360 can be included in the downhole portion of wellbore 300, or can be included in wellhead or surface systems, including combinations thereof. In implementations control module 360 can also include software such as an operating system, logs, utilities, drivers, databases, data structures, processing algorithms, networking software, and other software stored on a non- transient computer-readable medium. Wired or wireless communication, signaling, or power links can be employed between control module 360 and various other elements of valve control system 301, which can include electrical links run from a surface location to a downhole location.

[0046] In systems where hydraulic fluid for actuation of downhole valves is metered from surface equipment through long wellbore hydraulic lines, moving valves reliably to intermediate positions without some ldnd of mechanical or hydraulic ratcheting feature is exceedingly difficult due to static friction and overshoot problems. For example, the compressibility of hydraulic fluid in these long hydraulic lines combined with the difference between static friction and dynamic friction can lead to overshoot problems. Advantageously, the systems, devices, methods, and software presented herein readily can overcome these overshoot problems. Volumes for valve actuation presented herein can be much smaller than previous systems that meter fluid from the surface such that compressibility of the fluid is not a significant factor in valve actuation. Moreover, if fast-acting valve types are employed for isolation valves 3 5 and 316, then piston 351 can be made to stop reliably in an intermediate position based on a position feedback control loop, such as when position sensors are included in valve assembly 350. Thus, the associated valve 353 can be accurately controlled to intermediate open-closed states in addition to fully open or fully closed states.

[0047] In operation, Figures 3-5 each illustrate examples of various arrangements of crossover valves 320 and 340 for opening and closing of valve assembly 350 to allow or prevent fluid flow 355 through piping 352. In examples, each of crossover valves 320 and 340 can be in a first configuration or a second configuration, and thus can apply a plurality of differential pressure arrangements from pressure sources P I and P2 to valve assembly 350 through contamination prevention elements 330 and 335. Figure 3 illustrates an example of opening of valve 353. Figure 4 illustrates an example of closing of valve 353. Figure 5 illustrates a normalization of the contamination barrier. A more detailed discussion on the methods of operation of systems 300 and 301 is discussed in Figures 6 and 7 below. [0048] Figure 6 illustrates an example of a method of operation of valve control system 301 , according to various implementations. The illustrated stages of the method are examples and that any of the illustrated stages can be remo v ed, additional stages can be added, and the order of the illustrated stages can be changed.

[0049] As illustrated in Figure 6, in 601, valve control system 301 can receives pressure information associated with a plurality of pressure sources of a wellbore. In this embodiment, the pressure information can be determined by pressure monitors 31 1 and 312 which monitor pressure of the associated pressure source PI or P2. Pressure monitors 31 1 and 312 can transfer the pressure information to control module 360. Other information, such as temperature, can also be monitored and transferred to control module 360.

[0050] In 602, valve control system 301 can determine an actuation pressure arrangement from among the pressure information of the plurality of pressure sources which will actuate a valve assembly 350 from a present state to a desired state. The actuation pressure arrangement can include at feast a configuration of crossover valve 320 and of crossover valve 340 which can be used to apply pressures PI and P2 to valve assembly 350. The actuation pressure arrangement can consider the pressures PI and P2, namely that pressure PI is greater than P2 in this embodiment. Because system 300 can include further pressure sources, the actuation pressure arrangement can consider more pressure sources than PI and P2. The actuation pressure arrangement can also considers the present state and desired state of valve 353. For example, in Figure 3, initially valve 353 can be in a closed state, where piston 351 is positioned so as to move valve 353 over the aperture in tubing 352, The desired state can be an open state, where piston 351 is positioned to move valve 353 and allow the aperture in tubing 352 to be open. Thus, a greater pressure should be applied to the left side of piston 351 and a lesser pressure should be applied to the right side of piston 351 to achieve the desired state of valve 353. [0051 ] In 603, valve control system 301 can identify a first crossover arrangement for a first crossover valve and a second crossover arrangement for a second crossover valve based on the actuation pressure arrangement. Since the actuation pressure arrangement indicates that a higher pressure, such as PI , should be applied to the left side of piston 351 and a lower pressure, such as P2, should be applied to the right side of piston 351 , crossover valves 320 and 340 can be configured to route the proper pressures to the proper side of piston 351. Thus, the first crossover arrangement for crossover valve 320 can include any configuration of crossover valve, as long as crossover valve 340 is configured to apply the correct pressures as indicated by the actuation pressure arrangement and enough fluid remains in the reservoirs associated with contamination prevention elements 330 and 335. Control module 360 can monitor present actuation states for each of crossover valves 320 and 340 and base the first crossover arrangement and second crossover arrangement on these present actuation states. However, the present states of each of crossover valves 320 and 340 need not be taken into account if control module 360 is configured to apply predetermined crossover arrangements regardless of the present state of each of crossover valves 32.0 and 340. Assuming that crossover valve 32.0 is in the configuration where pressure routes for P I and P2 are 'crossed over' as indicated in the example of Figure 3 , then valve control system 301 can ensure that the second crossover arrangement for crossover valve 340 is also in the 'crossed over' configuration as indicated in example of Figure 3 and that the reservoir for contamination element 335 has enough clean fluid left. Along with the identified actuation pressure arrangement for applying PI and P2 to valve assembly 350, the identified crossover arrangements for each of crossover valves 320 and 340 can lead to piston 351 being forced to the right in the example of Figure 3, thus actuating valve 353 open.

[0052] In 604, to command crossover valve 320 and crossover valve 340 to be actuated in the proper position, configuration, or arrangement, valve control system 301 can transfer a first control signal for receipt by first crossover valve 320 to apply the pressures of at least two pressure sources of the well bore (i.e. PI and P2) to the contamination barrier using the first crossover arrangement. In 605, valve control system 301 can also transfer a second control signal for receipt by second crossover valve 340 to apply the pressures of the at least two pressure sources (i.e. PI and P2) from the contamination barrier to valve assembly 350 using the second crossover arrangement. The first and the second control signals can be transferred from control module 360 to the respective crossover valve. In response to the control signals, crossover valve 320 and crossover valve 340 can actuate according to the control signals, or can be delayed until a further control signal is transferred. In examples where a crossover valve is already in the desired configuration, then either no control signal can be transferred or the crossover valve can merely ignore the control signal.

[0053] In 606, valve control system 301 can initiate actuation of valve assembly 350 based on the applied actuation pressure arrangement. Isolation valves 315 and 316 can be commanded to open and thus allow pressures P i and P2 to be applied to the rest of the pressurized elements of valve control system 301. During the identification of the actuation pressure arrangement, including identification of the crossover arrangements, isolation valves 315 and 316 can remain closed so as to keep valve assembly 350 in a present state.

[0054] After isolation valves 315 and 315 are opened, the first crossover arrangement of crossover valve 320 can apply the actuation pressure arrangement of PI and P2 to contamination prevention elements 330 and 335. Specifically, PI can be applied through route 323 in crossover valve 320 to the dirty side of contamination prevention element 335, and P2 can be applied through route 324 in crossover valve 320 to the dirty side of contamination prevention element 330. In the example, because PI is a greater pressure than P2, this first crossover arrangement applied by crossover valve 320 can exert a higher pressure on contamination barrier 336 than on contamination barrier 331. Each of contamination prevention elements 330 and 335 can transfer the associated applied pressures while preventing fluid transfer across the associated contamination barrier. In turn, these pressures can be applied to crossover valve 340. As indicated in the example of Figure 3, the contamination barriers 331 and 336 can move responsive to the amount of clean and dirty fluid remaining in each reservoir, where some clean fluid 336 is forced out of the reservoir for element 335 and some clean fluid 333 is forced into the reservoir for element 330. The second crossover arrangement of crossover valve 340 can apply pressures transferred by contamination prevention elements 330 and 335 to valve assembly 350. Specifically, P I can be applied through route 344 in crossover valve 340 from the clean side of contamination prevention element 335, and P2 can be applied through route 343 in crossover valve 340 from the clean side of contamination prevention element 330.

[0055] Due to the actuation pressure arrangement and the crossover valve arrangements, pressure PI can be applied to the left side of piston 351 and P2 is applied to the right side of piston 351. Thus, a pressure differential is created across piston 351 , and piston 351 is forced to the right in the example of Figure 3, opening the associated valve 353. Fluid 355 can then flow through the open valve in piping 352. It should be noted that once piston 351 has moved according to the applied differential pressure, piston 351 will remain to the right, and valve 353 will remain open. Isolation valves 315 and 316 can then be commanded to close to prevent further flow of fluid or pressure changes from sources PI and P2.

[0056] Although an operation of system 300 as shown in the example of Figure 3 is used in the discussion above for Figure 6, the methods and operations discussed for Figure 6 can also be applied to the example of Figure 4. In the example of Figure 4, initially valve 353 can be in an open state, where piston 351 was previously positioned so as to move valve 353 away from the aperture in tubing 352. The desired state can be a closed state, where piston 351 is positioned to move valve 353 over the aperture in tubing 352. Thus, the actuation pressure arrangement can indicate that a greater pressure should be applied to the right side of piston 351 and a lesser pressure should be applied to the left side of piston 351 to achieve the desired state of valve 353.

[0057] In the example of Figure 4, because the actuation pressure arrangement indicates that a higher pressure, such as P 1 , should be applied to the right side of piston 351 and a lower pressure, such as P2, should be applied to the left side of piston 351 , crossover valves 320 and 340 can be configured to route the proper pressures to the proper sides of piston 351. Thus, the first crossover arrangement for crossover valve 320 can include any configuration of crossover valve, as long as crossover valve 340 is configured to apply the correct pressures as indicated by the actuation pressure arrangement and enough fluid remains in the reservoirs associated with contamination prevention elements 330 and 335. Assuming that crossover valve 320 is in the configuration where pressure routes for PI and P2 are 'crossed over' as indicated in Figure 4, then valve control system 301 can ensure that the second crossover arrangement for crossover valve 340 is not in a 'crossed over' configuration and that the reservoir for contamination element 335 has enough clean fluid left. Along with the identified actuation pressure arrangement for applying P 1 and P2 to valve assembly 350, the identified crossover arrangements for each of crossover valves 320 and 340 can lead to piston 351 being forced to the left in Figure 4, thus actuating valve 353 closed. Control module 360 can identify the actuation pressure arrangement and the crossover arrangements as discussed above. Once isolation valves 315-316 are opened, then valve assembly 350 can respond by actuating according to the actuation pressure arrangement and the crossover arrangements. Fluid 355 can then be prevented from flowing through the closed valve in piping 352. It should be noted that once piston 351 has moved according to the applied differential pressure, piston 351 can remain to the left, and valve 353 can remain closed. Isolation valves 315-316 can then be commanded to close.

[0058] Referring to contamination prevention elements 330 and 335 in the example of Figure 4. After isolation valves 315-315 are opened, the first crossover arrangement of crossover valve 320 can apply the actuation pressure arrangement of PI and P2 to contamination prevention elements 330 and 335 in a similar ma ner as done in the example of Figure 3. As indicated in the example of Figure 4, the contamination barriers 331 and 336 can move responsive to the remaining fluid in each reservoir. Assuming the example of Figure 3 precedes the example of Figure 4 in time, then further clean fluid 336 can be forced out of the reservoir for element 335 and further clean fluid 333 can be forced into the reservoir for element 330. Thus, the cylinder of contamination prevention element 335 can be further depleted of clean fluid, and the cylinder of contamination prevention element 330 can be further depleted of dirty fluid.

[0059] The example of Figure 5 illustrates a normalization of the contamination reservoir of element 335 from a depleted or empty state to a normalized state. Figure 7 illustrates an example of a method of operation of valve control system 301 according to the normalization configuration presented in the example of Figure 5. The illustrated stages of the method are examples and that any of the illustrated stages can be removed, additional stages can be added, and the order of the illustrated stages can be changed.

[0060] As illustrated in Figure 7, in 701, valve control system 301 can identify that contamination prevention elements 330 and 335 have reached desired travel limits. For example, Figure 4 shows barriers 331 and 336 near the limits of travel and the amount of clean fluid in the reservoir or element 335 as depleted. Further operation of valve control system 301 under the present crossover arrangement of the example of Figure 4 can be ineffective since barriers 331 and 336 cannot move sufficiently to displace enough fluid to move piston 351.

[0061 ] 111 702, valve control system 301 can receive pressure information associated with a plurality of pressure sources of a wellbore, namely pressure sources PI and P2 of the example of Figure 5. The pressure information can be determined by pressure monitors 31 1 and 312 which moni tor pressure of the associated pressure source P 1 or P2. Pressure monitors 31 1 and 312 can transfer the pressure information to control module 360. Other information, such as temperature, can also be monitored and can be transferred to control module 360.

[0062] In 703, valve control system 301 can determine a normalization pressure arrangement from among the pressure information of the plurality of pressure sources which will actuate a valve assembly 350 from a present state to a normalized state. The normalization pressure arrangement can include at least a configuration of crossover valve 32.0 and of crossover valve 340 which can be used to apply pressures PI and P2 to normalize barriers 331 and 335 and the associated reservoirs, thus allowing for further activation of valve assembly 350. The normalization pressure arrangement can consider the pressures PI and P2, namely that pressure PI is greater than P2 in this embodiment. The normalization pressure arrangement can also consider the present state and desired state of barriers 331 and 335 and associated reservoirs.

[0063] In the example of Figure 4, barriers 331 and 336 may have each reached the end of travel within the associated cylinder. Thus, a greater pressure can be applied to the top side of barrier 331 and a lesser pressure can be applied to the bottom side of barrier 331 to achieve the desired normalized state of contamination prevention element 330. Likewise, a greater pressure can be applied to the bottom side of barrier 336 and a lesser pressure can be applied to the top side of barrier 336 to achieve the desired normalized state of state contamination prevention element 335.

[0064] Iii 704, valve control system 301 can identify a first crossover arrangement for a first crossover valve and a second crossover arrangement for a second crossover valve based on the normalization pressure arrangement. Since the normalization pressure arrangement indicates that a higher pressure, such as P I, should be applied to the top side of contamination prevention element 330 and a lower pressure, such as P2, should be applied to the top side of contamination prevention element 335, crossover valves 320 and 340 can be configured to route the proper pressures to the proper side of contamination prevention elements 330 and 335, Control module 360 can monitor present positional states for each of barriers 331 and 336, or alternatively monitor reservoir fluid levels, and base the first crossover arrangement and second crossover arrangement on these present positional or reservoir states.

[0065] One possible normalization configuration for crossover valve 3:20 is as shown in the example of Figure 5 with a 'straight' routing configuration (i.e. non-'crossover') where PI is routed to contamination prevention element 330 and P2 is routed to

contamination prevention element 335. Crossover valve 340 can then be configured to be in a routing configuration to ensure that fluid flow can occur. For example, assuming initially that piston 351 is located as illustrated in the example of Figure 4 (i.e. a closed valve configuration), then crossover valve 340 can be configured to be in the 'straight' routing configuration during the normalization procedure, otherwise piston 351 will prevent fluid travel through the associated routes. If, on the other hand, piston 351 was initially located as illustrated in the example of Figure 3 (i.e. open valve configuration), then crossover valve 340 can be configured to be in the 'crossover' routing configuration during the normalization procedure. In further embodiments, crossover valve 340 can include a third pressure route, such as a loopback route, which can merely route fluid from the bottom end of contamination prevention element 330 to the bottom end of contamination prevention element 335 - bypassing valve assembly 350.

[0066] In 705, to command crossover valve 320 and crossover valve 340 to be actuated in the proper position, configuration, or arrangement, valve control system 301 can transfer a first control signal for receipt by first crossover valve 320 to apply the pressures of at least two pressure sources of the well bore (i.e. PI and P2) to the contamination barrier using the first crossover arrangement. In 706, valve control system 301 can also transfer a second control signal for receipt by second crossover valve 340 to apply the pressures of the at least two pressure sources (i.e. PI and P2) from the contamination barrier to valve assembly 350 using the second crossover arrangement. The first and the second control signals can be transferred from control module 360 to the respective crossover valve. In response to the control signals, crossover valve 320 and crossover valve 340 can actuate according to the control signals.

[0067] In 707, valve control system 301 can initiates normalization of barriers 331 and 336 based on the applied normalization pressure arrangement. Isolation valves 315 and 316 can be commanded to open and thus allow pressures PI and P2 to be applied to the rest of the pressurized elements of valve control system 301. During the identification of the normalization pressure arrangement, including identification of the crossover arrangements, isolation valves 315 and 316 can remain closed so as to keep barriers 331 and 336 in a present state.

[0068] Thus, after isolation valves 315-315 are opened, the first crossover arrangement of crossover valve 320 can apply the normalization pressure arrangement of PI and P2 to contamination prevention elements 330 and 335. Specifically, P I can be applied through route 321 in crossover valve 320 to the dirty side of contamination prevention element 330, and P2 can be applied through route 322 in crossover valve 320 to the dirty side of contamination prevention element 335. In the example, because PI is a greater pressure than P2, this first crossover arrangement applied by crossover valve 320 can exert a higher pressure on contamination barrier 331 than on contamination barrier 335. Each of contamination prevention elements 330 and 335 transfer the associated applied pressures, then responsively these pressures can be applied to crossover valve 340. As indicated in the example of Figure 5, the contamination barriers 331 and 336 can move responsive to the applied pressures, where some clean fluid 336 is forced out of the reservoir for element 330 and some clean fluid 333 is forced into the reservoir for element 335. The second crossover arrangement of crossover valve 340 can apply pressures transferred by contamination prevention elements 330 and 335 to valve assembly 350. Specifically, PI can be applied through route 341 in crossover valve 340 from the clean side of contamination prevention element 335, and P2 can be applied through route 342 in crossover valve 340 from the clean side of contamination prevention element 330.

[0069] Due to the normalization pressure arrangement and the crossover valve arrangements, pressure PI can be applied to the left side of piston 351 and P2 can be applied to the right side of piston 351. Thus, a pressure differential can be created across piston 35 L and piston 351 can be forced to the right in the example of Figure 5, opening the associated valve 353. Fluid 355 can then flow through the open valve in piping 352. It should be noted that once barriers 331 and 336 have normalized to a desired position or piston 351 reaches a limit of travel, isolation valves 315-316 can then be commanded to close.

[0070] Several cycles of normalization for barriers 331 and 336 may be required due to the difference in reservoir volume associated with each of contamination prevention elements 330 and 335 compared to that of piston assembly 350. In further normalization cycles, crossover valve 340 can be toggled to a different crossover arrangement to allow piston 351 to continue to travel in an opposite direction for each subsequent cycle. For example, after stages of the method described in Figure 7 for normalizing in the example of Figure 5, a second normalization cycle can be performed with crossover valve in the

'crossover' configuration. A third normalization cycle can then be performed with crossover valve 340 in the 'straight' configuration, and so on for further cycles until reservoirs of contamination prevention elements 330 and 335 have been normalized to a desired state. During each normalization procedure, piston 351 can be forced to different left and right positions according to the applied pressures in this embodiment (and consequently valve 353 will cycle through openings and closings).

[0071] To prevent valve .353 from opening and closing repeatedly during the normalization process, several alternate configurations can be employed. In

implementations, crossover valve 340 can include a loopback pressure route in addition to the 'straight' and 'crossover' routes to route pressure and fluid from the bottom of contamination prevention element 330 to the bottom of contamination prevention element 335 - bypassing piston assembly 350. In implementations, elements of valve assembly 350 can be configured so that during the normalization process, a full stroke of piston 351 is prevented such as by a ratcheting mechanism, controllable brakes or stops, or other elements. When a. partial stroke of piston 351 is employed, many more normalization cycles may be required than when a full stroke of piston 351 is employed due to the difference in volumes for a. full and partial stroke. In implementations, the normalization process can be performed during normal operation, such as when the crossover valves are arranged with each subsequent opening and closing of valve 353 to alternately deplete and refill the clean fluid in each contamination element reservoir.

[0072] Figure 8 illustrates an example of a wellbore system 800, according to various implementations. The wellbore system 800 can be an example of wellbore system 100 of Figures 1A and I B, or wellbore system 300 of Figures 3-5, although wellbore system 100, wellbore system 101, or wellbore system 300 can use other configurations. While Figure 8 illustrates various components contained in the wellbore system 800, Figure 8 illustrates one example of a wellbore system and additional components can be added and existing components can be removed.

[0073] As illustrates in Figure 8, wellbore system 800 can be associated with subterranean region 801. Wellbore system 800 can include wellhead system 810, casing 81 1; downhole valve assemblies 820 and 821 ; packers 825 and 826; pressure regions 830, 831, and 832; pipe sections 840, 841 , 842, and 843 ; pressure lines 850, 851 , 852, and 853; and resources 860-861.

[0074] Subterranean region 801 is shown for illustrative purposes only, and includes exemplasy dirt portions and rock strata as a portion of the underground region where the wellbore is made. Subterranean region 801 can contains resources 860 and 861 as underground natural resource regions, such as petroleum, natural gas, water, or other resources. In implementations, resource 860 can be at a different pressure than resource 861. This difference in pressure can be due to the natural depth and associated rock pressure, and can be influenced by pressures applied by wellhead system 810.

[0075] Wellhead system 810 can include systems and equipment to interface with the various downhole elements of wellbore system 800. Wellhead system 810 can include piping and pumps associated with pipe sections 840-843. Wellhead system 810 also includes control and processing systems for interfacing with downhole valve assemblies 820 and 821 to actuate associated valves and selectively apply wellbore pressures to valve control systems as discussed in the embodiments herein. In implementations, wellhead system 810 can include user interface elements such as displays, human-interface elements, or other control systems for operators to monitor pressures of the various pressure regions of wellbore system 800, initiate actuation of downhole valves, or initiate normalization processes, among other operations. Wellhead system 810 can include signaling links which are routed to downhole elements, such as pressure monitors, isolation valves, position sensors, crossover switching actuation and monitoring elements, and valve position sensors, among other downhole elements. The signaling links can include wired, wireless, or optical links for controlling downhole elements and receiving information from downhole elements.

[0076] Casing 81 1 can include a concrete, metal, plastic, or composite lining of the wellbore to isolate elements of the wellbore from the surrounding rock, dirt, and resources. Casing 811 can include perforated or open portions for accessing various underground elements such as resources 860 and 861 or rock strata, or for introducing materials into underground portions, such as drilling mud, Bracking fluid, proppant, water, or other fluids and materials. Casing 811 can also include further piping for introducing these materials into the wellbore regions or extracting materials from the wellbore. Some wellbore examples do not employ a casing, and thus casing 81 1 can be optional.

[0077] Downhole valve assemblies 820 and 821 include downhole valves and pistons as discussed herein, and can include DHFC valves. In the example of Figure 8, valve assembly 820 can divide a first pipe into two portions, namely pipe section 840 and 841, while valve assembly 821 can divide a second pipe into two portions, namely pipe section 842 and 843. As discussed herein, valve assemblies 820 and 821 can be actuated with wellbore pressure sources, namely pressure regions 830, 831, and 832 created by pressure- sealed sections of casing 811. The pressure-sealed sections can form discrete pressure regions 830, 831, and 832 between ones of packers 825 and 826 and wellhead 810. Press ure region 830 can be a first completion interval, pressure region 831 can be a second completion interval, and pressure region 832 can be an upper annulus portion of the wellbore. The various pressures of each region are indicated in Figure 8 by associated labeis 'P I,' 'P2,' and 'Ρ3.' To route the various pressure sources to the appropriate valve assembly, pressure lines 850-853 are employed. These pressure lines can include piping elements for transferring pressures and associated fluids from the respective pressure regions 830-832 to ones of val ve assemblies 820-821. In this embodiment, only two pressure sources are routed to each valve assembly, but in other embodiments three pressure sources can be routed to a particular valve assembly. It should be understood that the pressure sources routed to each valve assembly are merely exemplar}', and a different routing configuration can be employed, and valve assemblies can share ones of the pressure regions.

[0078] In the example of Figure 8, the pressure sources for each downhole valve assembly are not provided directly from surface pressure systems, i.e. via wellhead-originated hydraulic lines, but are subterranean in origin or associated with the various wellbore regions. In implementations, pressure can be applied from the surface to various wellbore regions during extraction of the resources, valve assemblies 820-821 only receive pressure and fluid from these wellbore regions, and not from discrete hydraulic pumps or lines from the surface. Advantageously, since typical volumes of wellbore pressure regions 830, 831 , and 832 are at feast hundreds of barrels, while the volume used to operate a typical downhole valve assembly is much smaller, such as 0.5 liter, a sufficient pressure volume is typically found in pressure regions 830, 831 , and 832 to operate downhole valve assemblies 820 and 821.

[0079] In operation of wellbore system 800, control system or operator of wellhead system 810 can desire to actuate valves associated with valve assemblies 820 and 821. This actuation can be to allow or restrict fluids to flow along pipe sections 840, 841, 842, and 843 during the normal operation of wellbore system 800. Actuation of valve assemblies 820 and 821 can be performed by a surface command or signaling, and can take into account the pressures of pressure regions 830, 831 , and 832. Pressures of pressure regions 830-832 can be applied to valve assemblies 820 and 821 over associated ones of pressure lines 850, 851, 852, and 853. Valve assemblies 820 and 821 can responsively actuate to an open or closed state based on the applied wellbore pressures. Wellhead 810 can command or control various crossover valves and isolation valves of valve assemblies 820 and 821 to actuate in accordance with identified pressure arrangements. Examples of operations of wellbore systems are illustrated in Figures 2, 6, and 7.

[0080] It should be noted that valves assemblies 820 and 821 can be employed to control pressurization or fluid flow between pipe sections, such as pipe sections 840, 841 , 842, and 843, when coupled between the associated pipe sections. In further embodiments, valve assemblies 820 and 821 can be employed to control pressurization or fluid flo between the pressure regions themselves, such as between pressure regions 830-832. Thus, when controlling pressurization or fluid flow between the pressure regions themselves, each of valve assemblies 820 and 821 can separate at least two pressure regions, while being actuated by at least two of the of pressure regions. The pressure regions separated by each valve assembly may not necessarily be the same pressure regions used for actuating the valves, although in implementations the same pressure regions can be employed to actuate the valves.

[0081] Figure 9 illustrates an example of control module 900, according to various implementations. Control module 900 can be an example of elements of valve control system 1 10 of Figures 1A and IB, control module 360 of Figure 3 , or wellhead system 810 of Figure 8, although valve control system 110, control module 360, or wellhead system 810 can use different configurations. While Figure 9 illustrates various components contained in the control module 900, Figure 9 illustrates one example of a control module and additional components can be added and existing components can be removed.

[0082] Control module 900 can include control interface 910, processing system 920, and user interface 940. Control interface 910, processing system 920, and user interface 940 can communicate over a common bus 950 for illustrative purposes. It should be understood that discrete links can be employed, such as data links, power links, optical links, wireless links, or other links. Control module 900 can be distributed or concentrated among multiple elements that together form the elements of Figure 9.

[0083] Control interface 910 can include circuitry and systems for receiving information from various elements of a wellbore system, such as pressure information, temperature information, reservoir levels, flow rates, positional information, actuation states, among other information. Control interface 910 can also transfer control signals and commands to the various elements of a wellbore system for instructing or actuating valves, among other operations. Control interface 910 can transfer control signals and receives information over ones of links 951 to and from downhoie elements. Control interface 910 can also include transceiver components, signal processing components, and amplifier circuitry for communicating with downhoie elements, or can include optical or wireless systems for communicating with downhoie elements. Control interface 910 can also receive command and control information and instructions from processing system 920 or user interface 940 for controlling the operations of control module 900. Links 951 can include signaling links for receiving information from downhoie elements and for transferring control signals to downhoie elements for actuating downhoie valves, among other operations. In implementations, links 951 can include power links for providing electrical power to downhoie elements, such as actuation motors, electronic valves, servos, sensors, transducers, or other downhoie elements.

[0084] Processing system 920 can include storage system 921. Processing system 920 can retrieve and execute software 930 from storage system 921. In implementations, processing system 920 can be located within the same equipment in which control interface 910 or user interface 940 are located. In implementations, processing system 920 can include

.) 1 specialized circuitry, and software 930 or storage system 921 can be included in the specialized circuitry to operate processing system 920 as described herein. Storage system 921 can include a non-transitory computer-readable medium such as a disk, tape, integrated circuit, server, flash memory, phase change memory, magnetic memory, optical memory, or some other memory device, and also may be distributed among multiple memory devices.

[0085] Software 930 can include an operating system, logs, utilities, drivers, networking software, and other software typically loaded onto a computer system. Software 930 can contain application programs, server software, firmware, or some other form of computer-readable processing instructions. When executed by processing system 920, software 930 can direct processing system 920 to operate as described herein.

[0086] Software 930 can include pressure information module 931 , pressure arrangement module 932, activation module 933, and normalization module 934. It should be understood that different configurations or operations can be employed, and individual modules of software 930 can be included in different equipment than control module 900. Pressure information module 931 can receive and processes pressure information received over Sinks 951 to determine various pressures of wellbore pressure regions. Pressure information module 931 can also receive and process other information such as temperature or positional information. Pressure arrangement module 932 can receive the pressure information from pressure information module 931 and processes the pressure information, a. present state of a downhole valve, and a desired state of a downhole valve to determine pressure arrangements for actuating the downhole valve from a present state to a desired state. Pressure arrangement module 932 can determine or store the state of downhole valves, crossover valves, and contamination barrier reservoirs for processing along with the pressure information. Once a pressure arrangement is determined, along with any corresponding crossover valve arrangements or configurations, then activation module 933 can format and transfer the arrangements as control signals for delivery to downliole elements over links 951. Activation module 933 can also receive user input and commands from user interface 940 for initiating actuation of downhole elements as well as for displaying downliole information to an operator. Normalization module 934 can monitor a state of containment prevention elements, such as reservoir levels or barrier positions, and determines when a normalization procedure should be performed. The normalization procedure can be initiated by an operator or can be performed automatically when containment prevention elements reach

predetermined operational limits. Normalization module 934 can also determine and monitor a quantity of normalization cycles which must be performed to normalize containment prevention elements.

[0087] User interface 940 can include equipment and circuitry for receiving user input and control, such as for receiving desired valve states or for communicating signals or commands to operate or actuate valves, crossover valves, pistons, or other downhole elements, among other operations. In implementations, examples of the equipment and circuitry for receiving user input and control can include push buttons, touch screens, selection knobs, dials, switches, actuators, keys, keyboards, pointer devices, microphones, transducers, potentiometers, non-contact sensing circuitry, accelerometers, or other human- interface equipment. User interface 940 can also include equipment to communicate pressure information, valve information, contamination element reservoir levels, or other downhole state information to a user of control module 900. In implementations, examples of the equipment to communicate information to the user can include displays, indicator lights, lamps, light-emitting diodes, hap tic feedback devices, audible signal transducers, speakers, buzzers, alarms, vibration devices, or other indicator equipment, including combinations thereof. [0088] Bus 950 can include a physical, logical, or virtual communication link, capable of communicating data, control signals, and communications, along with other information. Bus 950 can be encapsulated within the elements of control interface 910, processing system 920, or user interface 940, and can be a software or logical link. In other embodiments, bus 950 can use various communication media, such as air, space, metal, optical fiber, or some other signal propagation path, including combinations thereof. Bus 950 can be a direct link or might include various equipment, intermediate components, systems, and networks. Bus 950 can be a common link, shared link, or may be comprised of discrete, separate links.

[0089] In implementations, the components of the control module 900 need not be enclosed within a single enclosure or even located in close proximity to one another. Those skilled in the art will appreciate that the above-described componentry are examples only, as the control module 900 can include any type of hardware componentry, including any necessary accompanying firmware or software, for performing the disclosed

implementations. The control module 900 can also be implemented in part or in whole by electronic circuit components or processors, such as application-specific integrated circuits (ASICs) or field-programmable gate arrays (FPGAs).

[0090] Certain implementations described above can be performed as a. computer applications or programs. The computer program can exist in a variety of forms both active and inactive. For example, the computer program can exist as one or more software programs, software modules, or both that can be comprised of program instructions in source code, object code, executable code or other formats; firmware program(s); or hardware description language (HDL) files. Any of the above can be embodied on a computer readable medium, which include computer readable storage devices and media, and signals, in compressed or uncompressed form. Examples of computer readable storage devices and media include conventional computer system RAM (random access memory), ROM (readonly memory), EPROM (erasable, programmable ROM ), EEPROM (electrically erasable, programmable ROM), and magnetic or optical disks or tapes. Examples of computer readable signals, whether modulated using a carrier or not, are signals that a computer system hosting or running the present teachings can be configured to access, including signals downloaded through the Internet or other networks. Concrete examples of the foregoing include distribution of executable software program(s) of the computer program on a CD-ROM or via Internet download. In a sense, the Internet itself, as an abstract entity, is a computer readable medium. The same is true of computer networks in general.

[0091] While the teachings have been described with reference to examples of the implementations thereof, those skilled in the art will be able to make various modifications to the described implementations without departing from the true spirit and scope. The terms and descriptions used herein are set forth by way of illustration only and are not meant as limitations. In particular, although the method has been described by examples, the steps of the method may be performed in a different order than illustrated or simultaneously.

Furthermore, to the extent that the terms "including", "includes", "having", "has", "with", or variants thereof are used in either the detailed description and the claims, such terms are intended to be inclusive in a manner similar to the term "comprising." As used herein, the terms "one or more of and "at least one of with respect to a listing of items such as, for example, A and B, means A alone, B alone, or A and B, Further, unless specified otherwise, the term "set" should be interpreted as "one or more." Those skilled in the art will recognize that these and other variations are possible within the spirit and scope as defined in the following claims and their equivalents.

Claims

WHAT IS CLAIMED IS:

1. A method of operating a valve control system to control a valve in a wellbore, the method comprising:

identifying a differential pressure arrangement of a plurality of differential pressure arrangements for actuating the valve to a desired state based on a differential pressure of at least two pressure sources of the wellbore and a present state of the valve; and

actuating the valve from the present state to the desired state using the differential pressure arrangement of the at least two pressure sources,

2, The method of claim 1 , wherein identifying the differential pressure arrangement comprises receiving pressure information associated with a plurality of pressure sources of the wellbore monitored by pressure monitoring devices located in the wellbore, and determining the differential pressure arrangement from among the pressure information of the plurality of pressure sources which will actuate the valve from the present state to the desired state.

3. The method of claim 1 , wherein actuating the valve comprises transferring control signals to apply the differential pressure arrangement to the valve,

4, The method of claim 3, wherein transferring the control signals comprises transferring a first control signal for receipt by a first crossover valve to apply pressures of the at least two pressure sources in a first pressure arrangement to a contamination barrier, and transferring a second control signal for receipt by a second crossover valve to apply the pressures of the at least two pressure sources in a second pressure arrangement from the contamination barrier to the valve.

5. A method of operating a valve control system to control a valve in a wellbore, the method comprising:

monitoring pressure information associated with a plurality of press ure regions of the wellbore;

identifying a desired state of the valve;

identifying actuation pressures among the plurality of pressure regions to actuate the valve to the desired state based on the pressure information and a present state of the valve; and

applying the actuation pressures to the valve to actuate the valve to the desired state.

6. The method of claim 5, wherein monitoring the pressure information comprises monitoring pressures associated with the plurality of pressure regions of the wellbore with pressure transducers located in the wellbore.

7. The method of claim 5, wherein each of the pressure regions comprises at least one of an annuius and completion region of the w^rellbore.

8. The method of claim 5, w^rherein applying the actuation pressures to the valve to actuate the valve to the desired state comprises transferring actuation pressures via a contamination barrier between each of the actuation pressures and the valve, while preventing fluid transfer of each associated pressure region across the contamination barrier.

9. The method of claim 8, wherein applying the actuation pressures to the val ve to actuate the valve to the desired state comprises a first crossover valve selectively applying the actuation pressures from each associated pressure region to a dirty side of the contamination barrier.

10. The method of claim 9, wherein the first crossover valve comprises a selective pressure manifold configured to apply at least two arrangements of the actuation pressures to the dirty side of the contamination barrier.

1 1 . The method of claim 9, wherein applying the actuation pressures to the valve to actuate the valve to the desired state comprises a second crossover valve selectively applying the actuation pressures from a clean side of the contamination barrier to the valve.

12. The method of claim 11, wherein the second crossover valve comprises a selective pressure manifold configured to apply at least two airangements of the actuation pressures from the clean side of the contamination barrier to the valve.

13. A valve control system to control a valve in a welibore, comprising:

a control interface configured to monitor pressure information associated with a plurality of pressure regions of the w^reilbore, wherein the control interface is configured to identify a desired state of the valve and wherein the control interface is configured to identify actuation pressures among the pluraiity of press ure regions to actuate the valve to the desired state based on the pressure information and a present state of the valve; and

an actuation system configured to apply the actuation pressures to the valve to actuate the valve to the desired state.

14. The valve control system of claim 13, further comprising:

pressure transducers located in the welibore configured to measure pressures of each of the plurality of press ure regions and report the press ure information to the control interface.

15. The valve control system of claim 13, wherein each of the pressure regions comprises at least one of an anmilus and completion region of the welibore.

16. The valve control system of claim 13, further comprising:

a contamination barrier comprising a clean side and a dirty side, the contamination barrier positioned between each of the plurality of pressure regions and the valve and configured to transfer the actuation pressures while preventing fluid transfer of each associated pressure region across the contamination barrier.

17. The val ve control system of claim 16, further comprising:

a first crossover valve configured to selectively apply the actuation pressures from each associated pressure region to the dirty side of the contamination barrier.

18. The valve control system of claim 17, wherein the first crossover valve comprises a selective pressure manifold configured to apply at least two arrangements of the actuation pressures to the dirty side of the contamination barrier.

19. The val ve control system of claim 17, further comprising: a second crossover valve configured to selectively apply the actuation pressures from the clean side of the contamination barrier to the valve.

20. The valve control system of claim 19, wherein the second crosso ver valve comprises a selective pressure manifold configured to apply at least two arrangements of the actuation pressures from the clean side of the contamination barrier to the valve.