Patent Application
20240035349
The present disclosure relates generally to a bus system for use in subsea applications, such as for controlling electric actuators.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it may be understood that these statements are to be read in this light, and not as admissions of prior art.
Hydrocarbon fluids, such as oil and natural gas, are obtained from subterranean or subsea geologic formations, referred to as reservoirs, by drilling one or more wells that penetrates the hydrocarbon-bearing geologic formation. In subsea applications, various types of infrastructure may be positioned along a sea floor and coupled by electrical lines. For example, subsea trees may monitor and control the production of a subsea well via multiple subsea valves. Traditionally, subsea production systems use hydraulic actuators controlled by pressurized hydraulic fluids for operating the subsea valves on the subsea trees. Electric actuators may provide suitable control of the subsea valves while minimizing or eliminating the need for hydraulic pumps, fluids, and tubes, but generally come at the expense of increased electrical wiring and complexity. As such, depending on the scenario, interest in electric actuators for subsea applications, such as underwater safety values (USVs), may be tempered due to the increased complexity and costs for implementing and ensuring reliable communication and supply of electric power to the electric actuators.
A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below.
In one embodiment, a subsea production system may include a subsea tree that includes a first valve to control a flow of reservoir fluid through the subsea tree and a second valve to control the flow of the reservoir fluid through the subsea tree. The subsea production system may also include a bus system having multiple control modules that generate control signals to operate the first valve and the second valve. The bus system may also include a first electric bus that provides the control signals from a first control module to the first valve, a second electric bus that provides the control signals from a second control module to the second valve, and a third electric bus that provides the control signals from a third control module to the first valve and the second valve.
In another embodiment, an electric bus system may include multiple control modules that generate control signals to operate valves, wherein each valve is operated via an electric actuator. The electric bus system may also include a first electric bus to provide the control signals from a first control module or a second control module to a first electric actuator such that the wiring of the first electric bus couples the first control module to the first electric actuator and the second control module. The electric bus system may also include a second electric bus to provide the control signals to the first electric actuator and a second electric actuator from a third control module or a fourth control module, such that the wiring of the second electric bus couples the third control module to the first electric actuator and the fourth control module.
In another embodiment, a method may include providing, via a first bus, communication between a primary subsea control module and two or more electric actuators that operate respective production flowline valves of a subsea tree. The method may also include, in response to determining a fault in the communication between the primary subsea control module and the two or more electric actuators, providing, via the first bus, the communication to the two or more electric actuators via a secondary subsea control module. Additionally, the first bus couples the primary subsea control module and the secondary subsea control module with the two or more electric actuators, such that the two or more electric actuators are daisy chained between the primary subsea control module and the secondary subsea control module.
Various refinements of the features noted above may exist in relation to various aspects of the present disclosure. Further features may also be incorporated in these various aspects as well. These refinements and additional features may exist individually or in any combination. For instance, various features discussed below in relation to one or more of the illustrated embodiments may be incorporated into any of the above-described aspects of the present disclosure alone or in any combination. The brief summary presented above is intended only to familiarize the reader with certain aspects and contexts of embodiments of the present disclosure without limitation to the claimed subject matter.
These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
Certain embodiments commensurate in scope with the present disclosure are summarized below. These embodiments are not intended to limit the scope of the disclosure, but rather these embodiments are intended only to provide a brief summary of certain disclosed embodiments. Indeed, the present disclosure may encompass a variety of forms that may be similar to or different from the embodiments set forth below.
As used herein, the term “coupled” or “coupled to” may indicate establishing either a direct or indirect connection (e.g., where the connection may not include or include intermediate or intervening components between those coupled), and is not limited to either unless expressly referenced as such. The term “set” may refer to one or more items. Wherever possible, like or identical reference numerals are used in the figures to identify common or the same elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale for purposes of clarification.
Furthermore, when introducing elements of various embodiments of the present disclosure, the articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment,” “an embodiment,” or “some embodiments” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Furthermore, the phrase A “based on” B is intended to mean that A is at least partially based on B. Moreover, unless expressly stated otherwise, the term “or” is intended to be inclusive (e.g., logical OR) and not exclusive (e.g., logical XOR). In other words, the phrase A “or” B is intended to mean A, B, or both A and B.
Subsea production systems extract reservoir fluids such as oil, natural gas, or other resources of interest via one or more wells that penetrate a geological formation. In some embodiments, wells may be monitored and/or controlled via subsea trees that communicate with surface controllers and monitors. The subsea trees may include multiple valves to regulate the production flow of reservoir fluids out of the reservoir, as well as injecting other fluids, such as added chemicals. Moreover, the subsea tree may use hydraulic actuators, electric actuators, or a combination of hydraulic and electric actuators to motivate the valves. Additionally, the use of electric actuators may be accomplished or facilitated via an electric bus system.
In some embodiments, to reduce the risk of undesired flow of the reservoir fluid, subsea trees may have more than one valve in the production flow. For example, a production master valve (PMV) may be followed in the production flow by a redundant production wing valve (PWV), such that closure of either valve may stop production flow. In the event of communication or power failure, redundancy of the bus system to one or more valves (e.g., the PMV and/or the PWV) in the production flow may allow the subsea tree to maintain control of either or both valves and increase the reliability of the electric actuators of the subsea tree. For example, in some embodiments, the probability that at least one valve remains controllable may be increased by utilizing a looped redundant bus system.
In some embodiments, the looped redundant bus system may utilize two separated electric buses electrically connected to respective sets of electronic devices (e.g., electric actuators) and a shared bus connected to both sets of electronic devices. As such, three electric buses are divided amongst the various electronic devices such that each electronic device is electrically connected to the control modules of the subsea tree via two buses. Furthermore, in scenarios with multiple production flow valves, each of the separated electric buses may be coupled to different production flow valves, such as the PMV and the PWV, to increase diversity and redundancy. In some embodiments, each electronic device, including both the PMV and the PWV, may be coupled to all three electric buses. It should be understood that a greater number of buses and/or components in the looped redundant bus system are contemplated. However, it is recognized that currently available electric actuators may be set up for connection to two bus systems, and cost efficiency may be increased by utilizing available electric actuators with the redundancy of diversified buses and a shared bus.
In some embodiments, the wiring of the looped redundant bus system may propagate from one electronic device (e.g., electric actuator) to another and return back to the control modules of the subsea tree after reaching each device in a looped fashion. As such, in the case of a cable line failure, control information may be fed from either direction in the loop to maintain control and redundancy. Additionally or alternatively, the wiring may include a connection from the control modules of the subsea tree to each electronic device individually. However, such connections may increase the complexity of wiring and/or increase the costs associated with the wiring. Providing the looped redundant bus system as a daisy chained loop may provide increased reliability and redundancy while reducing or minimizing wire usage.
In some embodiments, the wiring of each of the three buses may be implemented as a single cable, further reducing wiring complexity and increasing resource (e.g., cost, space, wire, etc.) efficiency. For example, a twelve-wire cable may provide four legs for each bus (e.g., power positive, power negative/neutral, bus communication positive, and bus communication negative) in a single cable. Moreover, implementing the looped redundant bus system on a single cable may further decrease manufacturing costs as well as decrease complexity associated with manufacturing, implementation, and maintenance.
Additionally, in some embodiments, each electric bus may utilize a separate control module to provide a further increase to reliability and redundancy. Furthermore, in some embodiments, each end of each looped bus may utilize a separate control module such that each bus has two control modules communicating from either end of the loop. As such, at least a portion of a particular bus will still be active even in the event of a break in the wiring of the bus or the failure of one control module of the bus.
Additionally or alternatively, in some embodiments, the buses may be bridged at each electronic device or at a single electronic device to communicate with the shared bus or opposite separated bus in the event of a failure. For example, if all of the control modules for the shared bus and one of the separated buses became inoperable, one of the electronic devices on the operable separated bus may bridge the operable bus to the shared bus or the opposite separated bus to provide control signals to the devices not originally transmitted on the operable bus. Bridging the buses may provide for an additional redundancy without additional buses or wiring.
With the foregoing in mind,
In some embodiments, the pipes 44 may include an annulus path 46 surrounding the pipe 44 as an additional extraction path, input path (e.g., for chemical injection), or redundant path in case of a failure (e.g., blockage, breakage, etc.) in the pipe 44. The subsea tree 14 may also include a cross-over valve (XOV) 48 to tie the production flow 38 to the annulus path 46. Moreover, the annulus path 46 may have an annulus master valve (AMV) and/or an annulus wing valve (AWV) (not shown) as complements to the PMV 40 and/or PWV 42. Additional valves, such as a production swab valve 50, a flowline isolation valve 52, chokes 54, and/or chemical injection valves (CIVs) (not shown) may also be implemented as part of the subsea tree 14. Furthermore, the subsea tree 14 may include additional equipment 58, such as a tree cab and/or sensors 60 (e.g., pressure and/or temperature sensors), to monitor and/or assist in reservoir fluid production and/or pre-production processes.
The subsea tree 14 may also include a controller 62 having at least one processor 64 and/or at least one memory 66. In some embodiments, the controller 62 may include one or more subsea control modules (SCMs) 62 (e.g., as a bus master) for controlling electronic devices, such as electric actuators for the valves (e.g., PMV 40, PWV 42, AMV, AWV, XOV 48, the production swab valve 50, the flowline isolation valve 52, chokes 54, and/or CIVs). Moreover, in some embodiments, each SCM 68 may include their own processors 64 and memories 66. Additionally or alternatively, the controller 62 may be implemented as a centralized controller (e.g., disposed in part or entirely in the pipeline manifold 26, the distribution module 34, or other location) such that the controller 62 sends control signals to one or multiple subsea trees 14 from a centralized location in communication with the surface platform 30. As should be appreciated, the processor 64 may be implemented with any combination of general-purpose microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate arrays (FPGAs), programmable logic devices (PLDs), controllers, state machines, gated logic, discrete hardware components, dedicated hardware finite state machines, or any other suitable entities that may perform calculations or other manipulations of information. Moreover, the processor 64 may be implemented as one of multiple processors that work in conjunction with each other to perform the various functions described herein. Furthermore, the processor 64 may be operably coupled with the memory 66 to execute various algorithms stored in the memory 66 to perform the functions described herein. The memory 66 may include any suitable non-transitory medium for storing data and executable instructions, such as random-access memory, read-only memory, rewritable flash memory, hard drives, and optical discs.
In some embodiments, a looped redundant bus system 12 may be used for communications between the controller 62 (e.g., SCMs 68) and the electric actuators of the valves (e.g., PMV 40, PWV 42, AMV 72, AWV 74, XOV 48, the production swab valve 50, the flowline isolation valve 52, chokes 54, and/or CIVs) and/or other electronic devices/equipment 70, as shown in
As stated above, the buses (e.g., separated buses 78 and shared bus 82) may each connect to respective SCMs 68. Additionally, in some embodiments, the buses (e.g., separated buses 78 and shared bus 82) may loop back to the controller 62, such that control signals may be transmitted in either direction along the buses to communicate with the electronic devices 80. Additionally or alternatively, each end of a loop of a bus may utilize a separate SCM 68, such that each bus may have two SCMs 68 communicating from either end of the loop (e.g., either end of the buses). As such, at least a portion of a particular bus may still be active, even in the event of a break in the wiring of the bus or failure of an SCM 68 of the bus. For example, one SCM 68 of a particular bus may be designated as the primary SCM 68 and the other a secondary SCM 68 (e.g., as part of a dual-master or multi-master bus) to be used if the primary SCM 68 fails or the wiring fails. In some embodiments, to further increase diversity and reliability, the SCMs 68 at either ends of the loop may be housed in separate pressure housings 84A and 84B (cumulatively 84). Moreover, although discussed herein as individual control modules, the SCMs 68 may be implemented as individual circuits (e.g., sub-circuits, parallel circuits, etc.) and/or separate electronic circuit boards within a single SCM 68 or two SCMs 68 (e.g., one at either end of the loop).
Additionally or alternatively, the wiring may include a connection from the control modules of the subsea tree 14 to each electronic device individually. However, such connections may increase the complexity of wiring and/or increase the costs associated with wiring. Providing the looped redundant bus system 12 as a daisy chained loop 92 may provide increased reliability and redundancy while reducing or minimizing wire usage.
In some embodiments, the wiring of each of the three buses may be implemented as a single cable 94, further reducing wiring complexity and increasing resource (e.g., cost, space, wire, etc.) efficiency. For example, a twelve-wire cable may provide four legs for each bus (e.g., power positive, power negative/neutral, bus communication positive, and bus communication negative) in the single cable 94. Moreover, implementing the looped redundant bus system 12 on a single cable 94 may further decrease manufacturing costs as well as decrease complexity associated with manufacturing, implementation, and maintenance.
As stated above, it is desirable to maintain communication to and control of the electronic devices (e.g., electric actuators). Indeed, the redundancies discussed herein improve reliability by providing alternative paths for communications and power in the event of one or more failures (e.g., wire or electronics failure). In some embodiments, one of the electronic devices may create a bridge 96 between the buses to provide additional redundancy and reliability, as shown in
In some embodiments, the SCMs 68 and/or the electronic devices 80 may detect failures in the wiring or other electronics and switch operations to an operable bus or enable a bridge 96 accordingly. As such, in some embodiments, some or all of the electronic devices 80 may include circuitry (e.g., a processor 64 and/or memory 66) to determine failures/faults and facilitate, alone or in conjunction with the SCMs 68, switching communications to another SCM 68, another bus, or enabling a bridge 96. For example, in some embodiments, each set of electronic devices 80A and 80B may normally operate on their respective separated buses 78A and 78B. Under normal operations, this may increase available bandwidth on each separated bus 78 by having fewer devices on a particular bus. However, when a failure occurs, the controller 62 and/or electronic devices 80 may switch to communications using the SCM 68 at the other end of the loop 92, to the shared bus 82, or enable a bridge 96 to assist devices on a different separated bus 78. Furthermore, the electronic devices 80 may include default states (e.g., open or closed valve states) if it is determined that communications between the device and the controller 62 cannot be established.
As stated above, in some embodiments, the controller 62 may be implemented at a central location (e.g., the pipeline manifold 26, the distribution module 34, etc.) and control and/or operate one or more subsea trees 14.
The technical effects of the systems and methods described herein include a subsea tree with a looped redundant bus system that provides increased reliability with a more efficient use of resources such as wiring and reduces costs associated with manufacturing, implementation, and/or maintenance. Furthermore, although the above referenced flowchart is shown in a given order, in certain embodiments, process blocks may be reordered, altered, deleted, and/or occur simultaneously. Additionally, the referenced flowchart is given as an illustrative tool and further decision and process blocks may also be added depending on implementation.
As used herein, the terms “inner” and “outer”; “up” and “down”; “upper” and “lower”; “upward” and “downward”; “above” and “below”; “inward” and “outward”; and other like terms as used herein refer to relative positions to one another and are not intended to denote a particular direction or spatial orientation. The terms “couple,” “coupled,” “connect,” “connection,” “connected,” “in connection with,” and “connecting” refer to “in direct connection with” or “in connection with via one or more intermediate elements or members.”
The foregoing description, for purpose of explanation, has been described with reference to specific embodiments. However, the illustrative discussions above are not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. Moreover, the order in which the elements of the methods described herein are illustrated and described may be re-arranged, and/or two or more elements may occur simultaneously. The embodiments were chosen and described to best explain the principals of the disclosure and its practical applications, to thereby enable others skilled in the art to best utilize the disclosure and various embodiments with various modifications as are suited to the particular use contemplated.
Finally, the techniques presented and claimed herein are referenced and applied to material objects and concrete examples of a practical nature that demonstrably improve the present technical field and, as such, are not abstract, intangible or purely theoretical. Further, if any claims appended to the end of this specification contain one or more elements designated as “means for [perform]ing [a function] . . . ” or “step for [perform]ing [a function] . . . ,” it is intended that such elements are to be interpreted under 35 U.S.C. § 112(f). However, for any claims containing elements designated in any other manner, it is intended that such elements are not to be interpreted under 35 U.S.C. § 112(f).
This application is a non-provisional application claiming priority to and the benefit of U.S. Provisional Application No. 63/120,790, entitled “ELECTRIC ACTUATOR BUS SYSTEM,” filed Dec. 3, 2020, which is hereby incorporated by reference in its entirety for all purposes.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2021/061845 | 12/3/2021 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63120790 | Dec 2020 | US |
