Patent Publication Number: US-2022235625-A1

Title: Low power consumption electro-hydraulic system with multiple solenoids

Description:
TECHNICAL FIELD 
     The disclosure generally relates to the field of obtaining hydrocarbons (e.g., as oil or gas) from wells and, more specifically, to methods and equipment for completion of wellbores and control and improvement of production. 
     BACKGROUND 
     Various tools and tool systems have been developed to control, select, and/or regulate the production of hydrocarbon fluids and other fluids produced downhole from subterranean wells. Downhole well tools such as sliding sleeves, sliding windows, interval control valves, safety valves, lubricator valves, and gas lift valves are examples of control tools positioned downhole in wells. 
     Sliding sleeves and similar devices are placed in isolated sections of the wellbore to control fluid flow from the wellbore section. Multiple sliding sleeves and at least one interval control valve (ICV) can be placed in different isolated sections within tubing to jointly control fluid flow within the particular tubing section, and to commingle the various fluids within a common tubing interior. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the disclosure may be better understood by referencing the accompanying drawings. 
         FIG. 1  depicts a partial cross-sectional view of a well completion. 
         FIG. 2  depicts a first electro-hydraulic circuit for controlling an ICV. 
         FIG. 3  depicts a second electro-hydraulic circuit for controlling an ICV. 
         FIG. 4  depicts a plurality of control modules in a stacked configuration. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     The description that follows includes example systems and methods that embody examples of the disclosure. However, it is understood that this disclosure may be practiced without these specific details. For instance, this disclosure refers to electro-hydraulic circuits for controlling an interval control valve (ICV) in a completion system in illustrative examples. The embodiments of this disclosure can be also applied to controlling other downhole valves or instruments and can be implemented in any system combining hydraulic power and electric power. In other instances, well-known instruction instances, protocols, structures, and techniques have not been shown in detail in order not to obfuscate the description. 
     Systems for controlling multiple downhole tools, particularly ICVs, can include electric and hydraulic lines (electro-hydraulic systems). These systems use substantial power to control the downhole tools. A dual solenoid electro-hydraulic control system is disclosed herein that controls downhole tools with low power consumption. The system&#39;s power consumption can be low enough to be compatible with disconnect tools using inductive coupling. 
     In the disclosed electro-hydraulic control system, a control module is hydraulically coupled to an ICV to control the ICV. The control module is coupled to the surface via two hydraulic lines and two electrical power lines. The control module uses one hydraulic line as a “supply” line and the other line as a “return” line in the two-hydraulic line configuration. The control module includes two normally closed (NC) solenoid valves (SOVs), each coupled to one of the two electrical power lines, that can be controlled from the surface to open or close. The opening and closing of the two NC SOVs is controlled in cooperation with pressure being applied to at least one hydraulic line to operate (i.e., close or open) the ICV. Either hydraulic line can function as an “open” line or a “close” line referring to an opening or closing of the ICV. The control module can operate with a single hydraulic line in operable condition; should one of the hydraulic lines become damaged in a redundant multi-hydraulic line configuration, the control module can operate with the remaining hydraulic line(s). 
     The phrasing “hydraulically coupled with” refers to the coupling of components with a fluid conduit that is charged or under pressure and allows for the variations that may occur in various implementations. For instance, “component A is hydraulically coupled with component B” encompasses these non-limiting cases: A directly connected to B by a hydraulic conduit or A connected to B with one or more intervening components and multiple conduits therebetween. 
     Example Illustrations 
       FIG. 1  depicts a partial cross-sectional view of a well completion  100  that includes a low power electro-hydraulic circuit with two SOVs that control an ICV  112 . The electro-hydraulic circuit is formed with a hydraulic power system  113 , encapsulated control lines  107 , and a control module/hydraulic manifold assembly  111 . An ICV  112  controlled via the control module  111  can be considered part of the circuit or external to the circuit. The well completion  100  includes a wellbore  102  extending through, i.e., formed in, a subterranean formation  105  from a wellhead  106  located at a surface  103 . The wellbore  102  includes a casing string  108 . The casing string  108  can be at least partially cemented into the subterranean formation with cement  101 . Although cement  101  is shown near the surface  103 , the cement can extend the length of the wellbore  102 . Although the wellbore  102  is depicted as a single vertical wellbore, the wellbore  102  can include deviated or horizontal portions. Although only one casing string  108  is shown, multiple casing strings may be radially and/or circumferentially disposed around casing string  108 . 
     A tubing string  104  is positioned in the wellbore  102  inside the casing string  108 , forming an annulus  109  between the tubing string  104  and the casing string  108 . A completion component or sub-assembly (“sub”)  110  is included in (or physically coupled to) the tubing string  104 . Both the completion sub  110  and the tubing string  104  collectively (possibly with other completion subs and joined tubing) form the tubing string of the well completion  100 . 
     Encapsulated control lines  107  extend from the surface  103  of the wellbore  102  to the completion sub  110 . The control lines  107  at least include two electrical power lines and at least one hydraulic line. The control lines  107  can communicatively couple the completion sub  110  to a computing device that actuates a downhole tool, e.g., one or more valves. Hydraulic lines of the control lines  107  are coupled to the hydraulic system  113  and the control module  111 . The hydraulic power system  113  converts mechanical energy into hydraulic energy that is provided to the control module  111  via at least one of the hydraulic lines of the control lines  107 . 
     The completion sub  110  includes the control module  111  and the ICV  112 . The control module  111  is hydraulically coupled to the ICV  112  and includes portions of the control lines  107 . Although shown as components of the completion sub  110 , the control module  111  and/or the ICV  112  can be each coupled directly to the tubing string  104  and/or to one another, e.g., via threaded ends. 
     The ICV  112  controls flow between an interior and exterior of the tubing string  104 . For example, the exterior of the ICV  112  can be exposed to the annulus  109  and the ICV  112  can regulate flow between the interior of the tubing string  104  and the annulus  109 . 
       FIG. 2  depicts components of a control module of an electro-hydraulic circuit with two three-way normally closed solenoid valves for actuating an ICV. A control module  211  includes a housing  218 . The housing  218  can be coupled to tubing. The housing  218  protects the components of the control module  211 . The components of the control module  211  include a normally closed (NC) solenoid valve (SOV)  220 , a NC SOV  222 , a dynamic flow regulator  230 , a dynamic flow regulator  235 , a filter  242 , a filter  244 , a one-way flow regulator  290 , and a one-way flow regulator  292 . The components of the control module  211  are disposed within the housing  218 . 
     A hydraulic line  216  and a hydraulic line  217  route through the control module  211 . A “hydraulic line” as used herein refers to a hydraulic fluid conduit implemented as appropriate for the environment (e.g., a steel line or a hydraulic hose).  FIG. 2  depicts the hydraulic lines  216 ,  217  entering and exiting the housing  218  via separate apertures. Embodiments may route the hydraulic lines  216 ,  217  through shared apertures. Each of the hydraulic lines  216 ,  217  branches within the housing  218 . The hydraulic lines  216 ,  217  each branch to connect to different ports of the NC SOV  220 . Each of the hydraulic lines  216 ,  217  also branch to connect to different ports of the NC SOV  222 . The hydraulic lines  216 ,  217  route through one-way flow regulators  290  and  292 , respectively. For the branching of the hydraulic lines, embodiments can use a tee or a flow divider. The dynamic flow regulators provide flow control to ensure that the hydraulic circuit conforms to an operating range of pressures even with branching/splitting with tees. An electrical power line  219  and an electrical power line  221  route into the control module  211  through an aperture(s) of the housing  218  to connect to NC SOVs  220  and  222 , respectively. The dual NC SOV configuration provides redundancy and allows for actuation of the ICV  212  with a single hydraulic line and single energized NC SOV. Should a hydraulic line fail or suffer structural damage, the damaged and/or ineffective line can be used as the return line and the remaining hydraulic line retaining proper function then becomes the supply line. A hydraulic line  298  connects filter  242  to the ICV  212 , and a hydraulic line  299  connects filter  244  to the ICV  212 . 
     The ICV  212  is divided into two sides, an open side  214  and a close side  213 , by a double actuated floating piston  215 . The movement of the double-actuated floating piston  215  controls flow of fluid between the interior of a tubing string and an annulus. For example, movement of the double-actuated floating piston  215  towards the close side  213  increases flow between the interior of the tubing string and the annulus, and movement of the double-actuated floating piston  215  towards the open side  214  reduces flow between the interior of the tubing string and the annulus The double actuated floating piston  215  of the ICV  212  can be fully closed, i.e., fully blocking flow between the interior of the tubing string and the annulus, or fully open to allow maximum flow between the interior of the tubing string and the annulus. 
     . As depicted, both NC SOV  220  and NC SOV  222  are two-position, three-way NC SOVs. NC SOV  220  has a pressure port or P-port  220 P, a return port or R-port  220 R, and a control port or X-port  220 X. NC SOV  222  has a pressure port or P-port  222 P, a return port or R-port  222 R, and a control port or X-port  222 X. The control port of each SOV can also be referred to as a “C-port” instead of an X-port. 
     Each NC SOV has two states, an energized state and a deenergized state, corresponding to the two positions of the valve. In the deenergized state, each NC SOV  220 ,  222  is in a first, closed valve position that blocks hydraulic communication between the P-port and the X-port but allows hydraulic communication between the X-port and the R-port. In the energized state, each NC SOV  220 ,  222  is in a second, open valve position that allows hydraulic communication between the P-port and the X-port. The NC SOV  220  can be energized via the electrical power line  219 . A controller and an electrical power source that controls the NC SOVs  220 ,  222  can be disposed on the surface or at a location remote from the well. Similarly, the NC SOV  222  can be energized via the electrical power line  221  from the same or a different controller and the electrical power source to energize or deenergize the NC SOV  222 . 
     Hydraulic line branches throughout the electro-hydraulic circuit connect hydraulic line  216  and hydraulic line  217  to components within the system. A hydraulic line branch  216 A connects hydraulic line  216  to the P-port  220 P of NC SOV  220 . A hydraulic line branch  216 B connects hydraulic line  216  to the P-port  222 P of NC SOV  222 . A hydraulic line branch  217 A connects hydraulic line  217  to the R-port  220 R of NC SOV  220 , and a hydraulic line branch  217 B connects hydraulic line  217  to the R-port  222 R of NC SOV  222 . The one-way flow regulators  290  and  292  are disposed prior to the hydraulic line branches for  216 A,  217 A. At least one of one-way flow regulator  290  or one-way flow regulator  292  is composed of an adjustable flow regulator and bypass check valve, i.e., allowing unrestricted flow in a first direction but restricted flow in a second direction. 
     Each dynamic flow regulator  230 ,  235 , has an automatically adjustable variable-metering orifice which is configured to provide a constant volumetric flow rate therethrough. Each dynamic flow regulator  230 ,  235  senses the flow rate in terms of a differential pressure across a fixed orifice, and the variable metering orifice automatically adjusts to keep the volumetric flow rate constant therethrough over a range of pressure differentials across the dynamic flow regulators. The dynamic flow regulators  230 ,  235  protect the NC SOVs  220 ,  222  and can also be used to provide bidirectional choke capability to the ICV  212 . A hydraulic line  204  connects a first port of the dynamic flow regulator  230  to the X-port  220 X of NC SOV  220 , and a hydraulic line  205  connects a first port of the dynamic flow regulator  235  to the X-port  222 X of the NC SOV  222 . A hydraulic line  206  connects a second port of the dynamic flow regulator  230  to the filter  242 , and a hydraulic line  207  connects a second port of the dynamic flow regulator  235  to the filter  244 . 
     The X-port  220 X of the NC SOV  220  is hydraulically coupled to the dynamic flow regulator  230 , and the X-port  222 X of the NC SOV  222  is hydraulically coupled to the dynamic flow regulator  235 . Filter  242  is coupled between the close side  213  of the ICV  212  via hydraulic line  298  and the dynamic flow regulator  230  via the hydraulic line  206 , and the filter  244  is coupled between the open side  214  of the ICV  212  via hydraulic line  299  and the dynamic flow regulator  235  via the hydraulic line  207 . At least one of the filter  242  and the filter  244  can be a bidirectional filter. These filters are used to filter debris from the ICV and can utilize a dump line or bypass valve if either filter was to clog. The filters are supplementary to the electro-hydraulic circuit design and can be removed without impeding system functionality. 
     The one-way flow regulator  290  is oriented to allow unrestricted pressure supply on hydraulic line  216  into the control module  211  but restricts pressure (and therefore fluid flow) on hydraulic line  216  out of the control module (e.g., proceeding towards the surface or uphole). One-way flow regulator  292  is oriented to allow unrestricted pressure supply from hydraulic line  217  into the control module  211  but restricts pressure supply on the hydraulic line  217  from the electro-hydraulic circuit attempting to travel uphole (i.e., attempting to exit the control module  211 ). Each one-way flow regulator  290 ,  292  comprises an interior bypass check valve which allows the flow regulator to restrict excess pressure supplied from the circuit beyond what is permitted by the flow regulator. The one-way flow regulators  290 ,  292  allow ingress pressure (e.g., supplied from uphole) to pass through without restriction. One-way flow regulator  290  and one-way flow regulator  292  can mitigate potential damage and/or leak effects to hydraulic line  216  and hydraulic line  217 , respectively. 
     In operation, hydraulic line  216  can function as a supply line, and hydraulic line  217  is included to function as a return line. Building pressure on hydraulic line  216  while both the NC SOV  220  and NC SOV  222  are deenergized results in no movement of ICV  212 , as the P-ports  220 P and  222 P will block flow to the ICV  212  when both NC SOVs  220 ,  222  are deenergized. Likewise, building pressure on hydraulic line  216  while both NC SOV  220  and NC SOV  222  are energized also results in no movement of the ICV  212 , as there will be equal pressure on both the close side  213  and the open side  214  through the unimpeded flow through the energized NC SOVs  220 ,  222 . 
     To actuate the ICV  212  in a close direction, hydraulic line  216  is pressurized and NC SOV  220  is energized to allow hydraulic communication between the P-port  220 P and the X-port  220 X while NC SOV  222  remains deenergized. NC SOV  220  is energized via electrical power line  219 . With NC SOV  220  energized, pressure supplied from hydraulic line  216  forces fluid through hydraulic line branch  216 A to the P-port  220 P of the NC SOV  220 , where flow is further directed to the X-port  220 X and on through the dynamic flow regulator  230  via hydraulic line  204 . This flow or hydraulic pressure continues to the filter  242  via hydraulic line  206  to the close side  213  of the ICV  212  via the hydraulic line  298 . As differential pressure across the double-actuated floating piston  215  builds, pressure on the close side  213  will apply force on the double-actuated floating piston  215  and force fluid within the open side  214  out of the ICV  212  through filter  244  via hydraulic line  299 , through the dynamic flow regulator  235  via hydraulic line  207 , and to the X-port  222 X of the NC SOV  222  via the hydraulic line  205 . Flow continues through the deenergized NC SOV  222  from X-port  222 X towards R-port  222 R. From the R-port  222 R, pressure on the double-actuated floating piston  215  exerted by hydraulic line  216  further applies force or pushes fluid through the hydraulic line branch  217 B to hydraulic line  217  where pressure is relieved as return flow vents from the control module  211  towards a hydraulic power system via the one-way flow regulator  292 . In one or more embodiments, a second hydraulic line is not utilized, and the return flow from R-port  222 R is ported to an annulus. 
     To actuate the ICV  212  in an open direction, hydraulic line  216  is pressurized and NC SOV  222  is energized via electrical power line  221  while the NC SOV  220  remains deenergized. With the NC SOV  222  energized, pressure from hydraulic line  216  forces fluid through hydraulic line branch  216 B to the NC SOV  222  where fluid moves from P-port  222 P to X-port  222 X, through the dynamic flow regulator  235 , and through filter  244  to the open side  214  of the ICV  212 . The pressure on the double actuated floating piston  215 , supplied by hydraulic line  216 , builds in the open side  214 . As the pressure differential across the double-actuated piston  215  increases, pressure from hydraulic line  216  pushes the double-actuated piston  215  upwards. Fluid within the close side  213  is forced out of the ICV  212  to the filter  242  via the hydraulic line  298 , to the dynamic flow regulator  230  via the hydraulic line  206 , and to the NC SOV  220  via the hydraulic line  204  where flow continues from the X-port  220 X towards the R-port  220 R. Hydraulic line  217  is connected to R-port  220 R via hydraulic line branch  217 A and return flow from the close side  213  can vent from the control module  211  towards a hydraulic power system via one-way flow regulator  292 . In one or more embodiments, a second hydraulic line is not utilized, and the return flow from R-port  220 R is ported to an annulus to relieve pressure within the circuit. 
     In both directions of movement, movement of the ICV  212  can be halted by deenergizing the NC SOVs. Deenergizing NC SOV  220  halts closing of the ICV  212 , and deenergizing NC SOV  222  halts opening of the ICV  212 . This is because the electro-hydraulic circuit described by  FIG. 2  uses a pressure differential in the system to influence the movement of fluid and therefore movement of the double-actuated floating piston  215 . Energizing both NC SOVs would equalize pressure across the entire circuit, and deenergizing both NC SOVs would prevent pressure from a hydraulic supply line (either hydraulic line  216  or hydraulic line  217 ) from circulating through the system; pressure from hydraulic line  216  as the supply line would be unable to reach the ICV  212 , and pressure from hydraulic supply line  217  as the supply line would be unable to move the double-actuated floating piston  215  since both the open and close side of the ICV would receive fluid exerted at a near-identical pressure from the supply line. Pressure would quickly equalize across the circuit, and more specifically, the piston. 
     The hydraulic lines are interchangeable with respect to which line is the supply line and which is the return line, as mentioned above. Hydraulic line  217  can function as the supply line with hydraulic line  216  functioning as the return line, and the electro-hydraulic circuit would retain its functionality in actuating the ICV in either direction. In this configuration with hydraulic line  217  pressurized, movement in the open direction can be accomplished by energizing the NC SOV  220  to allow return flow from the close side  213  to vent through the filter  242 , dynamic flow regulator  230 , through energized NC SOV  220  from X-port  220 X to P-port  220 P, and through hydraulic line branch  216 A until reaching the return line in this instance, hydraulic line  216 . Likewise, in this configuration, movement in the close direction can be accomplished by energizing NC SOV  222  to allow return flow from the open side  214  to vent through the filter  244 , dynamic flow regulator  235 , through the energized NC SOV  222  from the X-port  222 X to the P-port  222 P, and through hydraulic line branch  216 B until reaching hydraulic line  216 . 
     As the electro-hydraulic circuit  200  disclosed above does not require two hydraulic lines (since the hydraulic line  217  is optional), the electro-hydraulic circuit  200  can be used in instances where it is necessary to reduce the number of control lines, e.g., since two electrical power lines are required to control the NC SOVs, the number of hydraulic lines in the system may be reduced to only a single hydraulic line. 
       FIG. 3  depicts a control module of an electro-hydraulic circuit with two three-way NC SOVs, a shuttle valve, and an inverse shuttle valve for actuating an ICV. The electro-hydraulic circuit illustrated in  FIG. 3  includes a control module  311  that is similar to the control module  211  of  FIG. 2 . The components of the control module  311  include the two NC SOVs  220  and  222 , the filters  242  and  244 , and the dynamic flow regulators  230  and  235 . Unlike the control module  211 , the control module  311  includes a shuttle valve  340 , and an inverse shuttle valve  350 , but does not include one-way flow regulators. 
     The shuttle valve  340  has three ports: an A-port  340 A, a B-port  340 B, and a C-port  340 C. The shuttle valve  340  includes internal components that allow hydraulic communication between A-port  340 A and C-port  340 C when the pressure on the A-port  340 A exceeds the pressure on the B-port  340 B. The shuttle valve  340  allows hydraulic communication between the B-port  340 B and the C-port  340 C when the pressure on the B-port  340 B exceeds the pressure on the A-port  340 A. Hydraulic communication between the ports of the shuttle valve  340  can be unidirectional or bidirectional. 
     The inverse shuttle valve  350  also has three ports: an A-port  350 A, a B-port  350 B, and a C-port  350 C. The inverse shuttle valve  350  includes internal components that allow hydraulic communication between A-port  350 A and C-port  350 C when the pressure on the A-port  350 A is less than the pressure on the B-port  350 B. The inverse shuttle valve  350  also allows hydraulic communication between B-port  350 B and C-port  350 C when the pressure on the B-port  350 B is less than the pressure on the A-port  350 A. Hydraulic communication between the ports of the inverse shuttle valve  350  can be unidirectional or bidirectional, similar to the shuttle valve  340 . 
     A-port  340 A of the shuttle valve  340  and A-port  350 A of the inverse shuttle valve  350  are both coupled to the hydraulic line  216 . A hydraulic line branch  216 C branches into hydraulic lines  216 D,  216 E. The hydraulic lines  216 D,  216 E respectively couple the A-port  340 A of the shuttle valve  340  and A-port  350 A of the inverse shuttle valve  350  to the line  216 C. B-port  340 B of the shuttle valve  340  and B-port  350 B of the inverse shuttle valve  350  are both coupled to the hydraulic line  217 . A hydraulic line branch  217 C branches into hydraulic lines  217 D,  217 E. The hydraulic lines  217 E,  217 D respectively couple the B-port  340 B of the shuttle valve  340  and B-port  350 B of the inverse shuttle valve  350  to the line  217 C. C-port  340 C of the shuttle valve  340  is coupled to P-port  220 P of the NC SOV  220  and to the P-port  222 P of NC SOV  222  via a hydraulic line  305 A and a hydraulic line  305 B, respectively. C-port  350 C of the inverse shuttle valve  350  is coupled to R-port  220 R of NC SOV  220  via a hydraulic line  204  and to R-port  222 R of NC SOV  222  via a hydraulic line  306 . 
     Example operation of the electro-hydraulic circuit is now described. Either hydraulic line  216  or hydraulic line  217  can function as a pressure supply line for actuating an ICV in an open or close direction, and the other hydraulic line can function as the return line. 
     Building pressure on the supply line while both NC SOV  220  and NC SOV  222  are deenergized results in no movement of the ICV  212 , as the P-ports  220 P and  222 P of the NC SOVs  220 ,  222  will block hydraulic communication between the ICV  212  and the pressure supply line when both NC SOVs are deenergized. Likewise, charging the supply line while both NC SOV  220  and NC SOV  222  are energized also results in no movement of the ICV  212 , as there will be equal pressure on both the close side  213  and the open side  214  through the open flow of the energized NC SOVs from P-ports  220 P and  222 P to X-ports  220 X and  222 X, respectively. 
     To actuate the ICV  212  in a close direction, the supply line is pressurized and NC SOV  220  is energized via electrical power line  219  while NC SOV  222  remains deenergized. With NC SOV  220  energized, hydraulic communication between the supply line and the P-ports  220 P and  222 P of the NC SOVs  220 ,  222  is allowed. Depending on which hydraulic line is used for the pressure supply line, hydraulic communication can exist between either the A-port  340 A or B-port  340 B and the C-port  340 C of the shuttle valve  340 . If hydraulic line  216  is the pressure supply line, pressure on hydraulic line  216  will force fluid through the hydraulic line branch  216 D where it enters the shuttle valve  340  at the A-port  340 A. The pressure will force a ball within the shuttle valve  340  into a seat located over B-port  340 B, effectively closing the port. Hydraulic communication is then allowed between the A-port  340 A and C-port  340 C before fluid flow is split along hydraulic lines  305 A and  305 B and travels to both NC SOVs  220 ,  222 . If hydraulic line  217  is the pressure supply line, the pressure on hydraulic line  217  will force fluid through hydraulic lines  217 C,  217 E where it enters the shuttle valve  340  at B-port  340 B. The pressure from hydraulic line  217  will force a ball within the shuttle valve  340  into a seat located over A-port  340 A, effectively closing the port. Hydraulic communication is then allowed between the B-port  340 B and the C-port  340 C before fluid flow is split and travels to both NC SOVs. Since NC SOV  222  is deenergized, pressure from the supply line is halted at P-port  222 P. 
     With the NC SOV  220  energized, pressure on the supply line forces fluid out from the C-port  340 C of shuttle valve  340  through NC SOV  220  from the P-port  220 P to the X-port  220 X. Pressure continues to force fluid through a hydraulic line  307  to the dynamic flow regulator  230  and to the filter  242  via a hydraulic line  309 . Flow continues to the close side  213  of the ICV  212  along hydraulic line  298 . The pressure on the double-actuated floating piston  215  forces fluid within the open side  214  out of the ICV  212  to filter  244  via hydraulic line  299 , to the dynamic flow regulator  235  via a hydraulic line  310 , and to the X-port  222 X of the NC SOV  222  via a hydraulic line  308 . In the NC SOV  222 , flow continues from X-port  222 X through the R-port  222 R. Pressure supplied by hydraulic line  216  continues to direct fluid flow from the R-port  222 R to the C-port  350 C of the inverse shuttle valve  350  via a hydraulic line branch  306  and a hydraulic line branch  304  and on to the return line via either A-port  350 A or B-port  350 B (depending on which hydraulic line is used for the return line). The inverse shuttle valve functions inversely from a standard shuttle valve. For example, if hydraulic line  216  is the pressure supply line and hydraulic line  217  is the return line, then the higher pressure along hydraulic line branch  216 D and A-port  350 A will close the A-port  350 A, and hydraulic communication will be permitted between C-port  350 C and the B-port  350 B, where the pressure forces fluid out of the electro-hydraulic circuit via the return line: hydraulic line  217 . Likewise, when hydraulic line  216  is the return line, the lower pressure on A-port  350 A of the inverse shuttle valve  350  will close the B-port  350 B and hydraulic communication will be permitted between the C-port  350 C and the A-port  350 A, where pressure from the supply line will eventually force fluid out of the electro-hydraulic circuit and pressure will relieve via the return line, hydraulic line  216 . 
     To actuate the ICV  212  in an open direction, the supply line is pressurized, and NC SOV  222  is energized via electrical power line  221  while NC SOV  220  remains deenergized. With NC SOV  222  energized, hydraulic communication between the supply line and the P-ports of the NC SOVs is allowed. Depending on which hydraulic line is used for the pressure supply line, hydraulic communication can exist between either the A-port  340 A or B-port  340 B and the C-port  340 C. If hydraulic line  216  is the supply line, the pressure on the hydraulic line  216  will force fluid through the hydraulic line branch  216 D where it enters the shuttle valve  340  at the A-port  340 A. The pressure will force a ball within the shuttle valve  340  into a seat located over B-port  340 B, effectively closing this port. Hydraulic communication is then allowed between the A-port  340 A and C-port  340 C before fluid flow is split and travels to both NC SOVs  220  and  222  via hydraulic lines  305 A and  305 B, respectively. If hydraulic line  217  is the pressure supply line, the pressure on the hydraulic line  217  will force fluid through hydraulic lines  217 C,  217 D where it enters the shuttle valve  340  at the B-port  340 B. The pressure from hydraulic line  217  will force a ball within the shuttle valve  340  into a seat located over A-port  340 A, effectively closing this port. Hydraulic communication is then allowed between B-port  340 B and C-port  340 C before fluid flow is split and travels to both NC SOVs. Since NC SOV  220  is deenergized, pressure from the supply line is halted at P-port  220 P. 
     With the NC SOV  222  energized, pressure on the supply line forces fluid out from the C-port  340 C of shuttle valve  340  through NC SOV  222  from P-port  222 P to X-port  222 X. Pressure continues to force fluid through the dynamic flow regulator  235  via hydraulic line  308 , through the filter  244  via hydraulic line  310 , and to the open side  214  of the ICV  212  via hydraulic line  299 . The pressure on the double-actuated floating piston  215  forces fluid within the close side  213  out of the ICV  212  via hydraulic line  298  to the filter  242 , to the dynamic flow regulator  230  via hydraulic line  309 , and to the NC SOV  220  via hydraulic line  307  where flow through the NC SOV  220  proceeds from the X-port  220 X towards the R-port  220 R. Pressure supplied by the supply line continues to direct fluid flow from the R-port  220 R to the C-port  350 C of the inverse shuttle valve  350  via hydraulic line  304  and on to the return line via either A-port  350 A or B-port  350 B (depending on which hydraulic line is used for the return line). The inverse shuttle valve functions inversely from a standard shuttle valve. For example, if hydraulic line  216  is the pressure supply line and hydraulic line  217  is the return line, then the higher pressure along hydraulic line branch  216 D and A-port  350 A will close A-port  350 A, and hydraulic communication will be permitted between the C-port  350 C and the B-port  350 B, where the supplied pressure forces fluid out of the electro-hydraulic circuit via the return line; hydraulic line  217 . Likewise, when hydraulic line  216  is the return line, the lower pressure on A-port  350 A of the inverse shuttle valve  350  will close the B-port  350 B and hydraulic communication will be permitted between the C-port  350 C and the A-port  350 A. where pressure from the supply line will eventually force fluid out of the electro-hydraulic circuit via the return line, hydraulic line  216 . 
     The ability of the disclosed electro-hydraulic circuits to use either hydraulic line provides redundancy in instances where there is danger of losing functionality of one of the hydraulic lines, e.g., due to shifts in the wellbore or a workover or treatment that damages the integrity of a hydraulic line. 
       FIG. 4  depicts a plurality of electro-hydraulic control modules in a stacked configuration. Two control modules are shown: control module  411  and control module  413 . Each of the control modules  411 - 413  are similar to either the control module  211  of  FIG. 2 , the control module  311  of  FIG. 3 , or a combination of the two (e.g., control module  411  can comprise components of control module  211  and control module  413  can comprise components of control module  311 ). Each control module is correlated to its own pay zone, i.e., hydrocarbon-producing formation, when in the stacked configuration. The control modules  411 ,  413  are hydraulically connected to ICVs  412 A,  412 B, respectively. The control module  411  is connected to the ICV  412 A by hydraulic lines  498 A,  499 A. The control module  413  is connected to the ICV  412 B by hydraulic lines  498 B,  499 B. The control modules  411 ,  413  are said to be “stacked” because shared hydraulic lines are used to activate more than one control module. As depicted in  FIG. 4 , either hydraulic line  416  or hydraulic line  417  can function as the supply line and the other as the return line. In an instance of damage to one of the hydraulic lines, the damaged line will be used as the return line and the undamaged line used as the supply line. In normal operation, either hydraulic line can be used as an open line or a close line to open or close the ICVs. The hydraulic line  416  and hydraulic line  417  can use a tee to branch to the control modules  411 ,  413 . A dynamic flow regulator can be placed on hydraulic line  416  and/or hydraulic line  417  above and/or between control modules to provide flow control to facilitate conformance with an operating pressure range of the control modules. The placement of the dynamic flow regulator above and/or between control modules on hydraulic line  416  and/or hydraulic line  417  may depend on a variety of factors including the distance between control modules, the depth of a control module, and the pressure exerted on a control module by a hydraulic power system. 
     With an applied pressure on a hydraulic supply line, the NC SOVs in each of the control modules  411 - 413  can be controlled to open or close their respective ICV. For example, with hydraulic line  416  acting as a supply line, pressure can be exerted on the two control modules  411 - 413 . With the supply line pressurized, one of two NC SOVs in control module  411  can be energized to open the ICV  412 A in coordination with the pressure in the supply line, and one of two NC SOVs in control module  413  can be energized to open ICV  412 B in coordination with the pressure in the supply line, or both can occur simultaneously. In another example, with the supply line pressurized, one of two NC SOVs in control module  411  (e.g., NC SOV  220 ) can be energized to close ICV  412 A in coordination with the pressure in the supply line, and one of two NC SOVs in control module  413  can be energized to close ICV  412 B in coordination with the pressure in the supply line, or both can occur simultaneously. Thus, stacking the control modules allows the system to use a shared hydraulic line(s) for control of a plurality of ICVs. In a single control module configuration, the hydraulic line terminates within or proximate to the “last” or “stack termination” control module (i.e., the last control module in the series). 
     While the aspects of the disclosure are described with reference to various implementations and exploitations, it will be understood that these aspects are illustrative. In general, techniques for opening and closing ICVs as described herein may be implemented with facilities consistent with any hardware system or hardware systems. Many variations, modifications, additions, and improvements are possible. For instance, some embodiments may split the components of the disclosed electro-hydraulic controller into different housings. This may be done to satisfy space constraints. When components of the electro-hydraulic controller are disposed within different housings, a tee block or a flow divider is used for branching of hydraulic lines into the different housings. In addition, embodiments are not limited to placement of the dynamic flow regulator as disclosed herein. While the disclosed illustrations are based on a preference to place the dynamic flow regulator proximate to the ICV actuated by the electro-hydraulic controller, embodiments can place the dynamic flow regulator anywhere on a hydraulic line among the components that form an electro-hydraulic controller. In embodiments with components disposed within different housings, a dynamic flow regulator may be disposed within each housing or fewer than all of the housings. 
     Plural instances may be provided for components, operations or structures described herein as a single instance. Finally, boundaries between various components, operations and data stores are somewhat arbitrary, and particular operations are illustrated in the context of specific illustrative configurations. Other allocations of functionality are envisioned and may fall within the scope of the disclosure. In general, structures and functionality presented as separate components in the example configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements may fall within the scope of the disclosure. 
     Use of the phrase “at least one of” preceding a list with the conjunction “and” should not be treated as an exclusive list and should not be construed as a list of categories with one item from each category, unless specifically stated otherwise. A clause that recites “at least one of A, B, and C” can be infringed with only one of the listed items, multiple of the listed items, and one or more of the items in the list and another item not listed. 
     Example Embodiments 
     Embodiment #1: A system comprising: tubing; an interval control valve (ICV) coupled to the tubing, the ICV having an open side and a close side; a first hydraulic conduit and a second hydraulic conduit coupled with a hydraulic power system; a first electrical power line and a second electrical power line coupled with an electrical power source; and a set of one or more housings that enclose, a first one-way flow regulator coupled with the first hydraulic conduit and hydraulically coupled with a first normally closed (NC) solenoid valve (SOV) and a second NC SOV; the first NC SOV coupled with the first electrical power line; the second NC SOV coupled with the second electrical power line; a second one-way flow regulator coupled with the second hydraulic conduit and hydraulically coupled with the first NC SOV and the second NC SOV; a first dynamic flow regulator having a first port that is hydraulically coupled to the first NC SOV, and having a second port that is hydraulically coupled to the close side of the ICV; and a second dynamic flow regulator having a first port that is hydraulically coupled to the second NC SOV and having a second port hydraulically coupled to the open side of the ICV. 
     Embodiment #2: The system of Embodiment 1, wherein the first and second dynamic flow regulators are hydraulically coupled to the ICV via a third hydraulic conduit and a fourth hydraulic conduit, respectively. 
     Embodiment #3: The system of any one of Embodiments 1-2, wherein the second port of the first dynamic flow regulator is hydraulically coupled with a first port of a first filter and a second port of the first filter is hydraulically coupled to the close side of the ICV, the second port of the second dynamic flow regulator is hydraulically coupled with a first port of a second filter, and the second port of the second filter is hydraulically coupled to the open side of the ICV. 
     Embodiment #4: The system of any one of Embodiments 1-3, wherein the first dynamic flow regulator and the second dynamic flow regulator each have an automatically adjustable variable-metering orifice. 
     Embodiment #5: The system of any one of Embodiments 1-4, wherein the first dynamic flow regulator and the second dynamic flow regulator are configured to maintain a constant differential pressure across each dynamic flow regulator. 
     Embodiment #6: The system of any one of Embodiments 1-5, wherein the first one-way flow regulator being hydraulically coupled with the first and second NC SOVs comprises the first one-way flow regulator being hydraulically coupled with a P-port of the first NC SOV and a P-port of the second NC SOV, and wherein the second one-way flow regulator being hydraulically coupled with the first and second NC SOVs comprises the second one-way flow regulator being hydraulically coupled with a R-port of the first NC SOV and a R-port of the second NC SOV. 
     Embodiment #7: The system of Embodiment 6, wherein the first dynamic flow regulator having the first port that is hydraulically coupled to the first NC SOV comprises the first port of the first dynamic flow regulator being hydraulically coupled to an X-port of the first NC SOV, and wherein the second dynamic flow regulator having the first port that is hydraulically coupled to the second NC SOV comprises the first port of the second dynamic flow regulator being hydraulically coupled to an X-port of the second NC SOV. 
     Embodiment #8: An apparatus comprising: a first hydraulic conduit and a second hydraulic conduit; a first one-way flow regulator hydraulically coupled with the first hydraulic conduit and hydraulically coupled with a first normally closed (NC) solenoid valve (SOV) and a second NC SOV; a second one-way flow regulator hydraulically coupled with a second hydraulic conduit and hydraulically coupled with the first NC SOV and the second NC SOV; a first dynamic flow regulator that is hydraulically coupled with the first NC SOV; and a second dynamic flow regulator that is hydraulically coupled with the second NC SOV. 
     Embodiment #9: The apparatus of Embodiment 8, wherein the first one-way flow regulator being hydraulically coupled with the first and second NC SOVs comprises the first one-way flow regulator being hydraulically coupled with a P-port of the first NC SOV and a P-port of the second NC SOV, and wherein the second one-way flow regulator being hydraulically coupled with the first and second NC SOVs comprises the second one-way flow regulator being hydraulically coupled with a R-port of the first NC SOV and a R-port of the second NC SOV. 
     Embodiment #10: The apparatus of Embodiment 9, wherein the first dynamic flow regulator being hydraulically coupled with the first NC SOV comprises a first port of the first dynamic flow regulator being hydraulically coupled with an X-port of the first NC SOV, and wherein the second dynamic flow regulator being hydraulically coupled with the second NC SOV comprises a first port of the second dynamic flow regulator being hydraulically coupled to an X-port of the second NC SOV. 
     Embodiment #11: The apparatus of Embodiment 10, wherein a second port of the first dynamic flow regulator is adapted to be hydraulically coupled with a close side of an interval control valve (ICV) that is distinct from the apparatus and a second port of the second dynamic flow regulator is adapted to be hydraulically coupled with an open side of an interval control valve (ICV) that is distinct from the apparatus. 
     Embodiment #12: The apparatus of any one of Embodiments 10-11, further comprising a first filter adapted to be hydraulically coupled between a second port of the first dynamic flow regulator and a close side of an interval control valve (ICV) that is distinct from the apparatus, and a second filter adapted to be hydraulically coupled between a second port of the second dynamic flow regulator and an open side of an ICV that is distinct from the apparatus. 
     Embodiment #13: An apparatus comprising: a first hydraulic conduit and a second hydraulic conduit; a first normally closed (NC) solenoid valve (SOV) and a second NC SOV; a first dynamic flow regulator hydraulically coupled with the first NC SOV; a second dynamic flow regulator hydraulically coupled with the second NC SOV; an inverse shuttle valve hydraulically coupled between the first hydraulic conduit and both of the first and the second NC SOVs and hydraulically coupled between the second hydraulic conduit and both of the first and second NC SOVs; and a shuttle valve hydraulically coupled between the first hydraulic conduit and both the first and second NC SOVs and hydraulically coupled between the second hydraulic conduit and both the first and second NC SOVs. 
     Embodiment #14: The apparatus of Embodiment 13, wherein the first dynamic flow regulator being hydraulically coupled with the first NC SOV comprises a first port of the first dynamic flow regulator being hydraulically coupled with an X-port of the first NC SOV and wherein the second dynamic flow regulator being hydraulically coupled with the second NC SOV comprises a first port of the second dynamic flow regulator being hydraulically coupled with an X-port of the second NC SOV. 
     Embodiment #15: The apparatus of Embodiment 14 further comprising a first filter and a second filter, wherein a first port of the first filter is hydraulically coupled with a second port of the first dynamic flow regulator and a second port of the first filter is adapted to hydraulically couple with a close side of an interval control valve and wherein a first port of the second filter is hydraulically coupled with a second port of the second dynamic flow regulator and a second port of the second filter is adapted to hydraulically couple with an open side of an interval control valve. 
     Embodiment #16: The apparatus of any one of Embodiments 13-15, wherein the inverse shuttle valve being hydraulically coupled between the first hydraulic conduit and both of the first and the second NC SOVs and hydraulically coupled between the second hydraulic conduit and both of the first and the second NC SOVs comprises an A-port of the inverse shuttle valve being hydraulically coupled with the first hydraulic line, a B-port of the inverse shuttle valve being hydraulically coupled with the second hydraulic line, and a C-port of the inverse shuttle valve being hydraulically coupled with an R-port of the first NC SOV and with an R-port of the second NC SOV. 
     Embodiment #17: The apparatus of any one of Embodiments 13-16, wherein the shuttle valve being hydraulically coupled between the first hydraulic conduit and both of the first and the second NC SOVs and hydraulically coupled between the second hydraulic conduit and both of the first and the second NC SOVs comprises an A-port of the shuttle valve being hydraulically coupled with the first hydraulic line, a B-port of the shuttle valve being hydraulically coupled with the second hydraulic line, and a C-port of the shuttle valve being hydraulically coupled with a P-port of the first NC SOV and with a P-port of the second NC SOV. 
     Embodiment #18: The apparatus of any one of Embodiments 13-17 further comprising a housing. 
     Embodiment #19: The apparatus of any one of Embodiments 13-18, wherein the first dynamic flow regulator and the second dynamic flow regulator each have an automatically adjustable variable-metering orifice. 
     Embodiment #20: The apparatus of any one of Embodiments 13-19, wherein the first dynamic flow regulator and the second dynamic flow regulator are configured to maintain a constant differential pressure across each dynamic flow regulator.