U.S. patent application number 11/682694 was filed with the patent office on 2008-09-11 for subsea communications multiplexer.
This patent application is currently assigned to SCHLUMBERGER TECHNOLOGY CORPORATION. Invention is credited to Gregor Deans.
Application Number | 20080217022 11/682694 |
Document ID | / |
Family ID | 39284696 |
Filed Date | 2008-09-11 |
United States Patent
Application |
20080217022 |
Kind Code |
A1 |
Deans; Gregor |
September 11, 2008 |
SUBSEA COMMUNICATIONS MULTIPLEXER
Abstract
A system for communicating between a surface facility and a
subsea production control system includes a communications device
proximate the water surface. The water surface communications
device has at least one communication interface. A communications
device is functionally associated with a wellhead or subsea
structure proximate the water bottom. The water bottom
communications device has at least one communication interface. A
communication channel extends between the surface communication
device and the water bottom communication device. A multiplexer is
functionally coupled to the communication interface on each of the
surface and water bottom communication devices. At least two remote
devices are functionally coupled to the water bottom multiplexer.
The remote devices comprise at least one of a sensor and a control.
At least two corresponding devices are coupled to the surface
multiplexer. The corresponding devices include at least one of a
signal acquisition device and a control signal generating
device.
Inventors: |
Deans; Gregor; (Paris,
FR) |
Correspondence
Address: |
SCHLUMBERGER RESERVOIR COMPLETIONS
14910 AIRLINE ROAD
ROSHARON
TX
77583
US
|
Assignee: |
SCHLUMBERGER TECHNOLOGY
CORPORATION
Sugar Land
TX
|
Family ID: |
39284696 |
Appl. No.: |
11/682694 |
Filed: |
March 6, 2007 |
Current U.S.
Class: |
166/338 |
Current CPC
Class: |
H04L 67/12 20130101;
E21B 47/12 20130101; H04J 15/00 20130101 |
Class at
Publication: |
166/338 |
International
Class: |
E21B 7/00 20060101
E21B007/00 |
Claims
1. A system for communicating between a surface facility and a
subsea production control system, comprising: a communications
device proximate the water surface, the water surface
communications device having at least one communication interface;
a communications device functionally associated with the subsea
production control system proximate the water bottom, the water
bottom communications device having at least one communication
interface; a communication channel extending between the surface
communication device and the water bottom communication device; a
multiplexer functionally coupled to the communication interface of
each of the water bottom and water surface communication devices;
at least two remote devices functionally coupled to the water
bottom multiplexer, the devices comprising at least one of a sensor
and a control; and at least two corresponding devices coupled to
the surface multiplexer, the at least two corresponding devices
comprising at least one of a signal acquisition device and a
control signal generating device.
2. The system of claim 1 wherein at least one remote device is
disposed proximate the water bottom.
3. The system of claim 1 wherein at least one remote device is
disposed within a wellbore.
4. The system of claim 1 wherein at least one remote device
comprises a pressure sensor.
5. The system of claim 1 wherein at least one remote device
comprises a temperature sensor.
6. The system of claim 1 wherein at least one remote device
comprises a pump.
7. The system of claim 1 wherein at least one remote device
comprises a valve.
8. The system of claim 1 wherein the communication channel
comprises electrical cable.
9. The system of claim 1 wherein the communication channel
comprises a fiber optic communication line.
10. The system of claim 1 wherein the subsea production control
system comprises at least one of a, fibre optic monitoring line, a
sand detection sensor, a flowrate sensor, a corrosion sensor, a
deposition sensor, a micro-seismic sensor, a strain sensor, a
vibration sensor, and a position sensor.
11. The system of claim 1 wherein the water bottom multiplexer is
disposed within a housing with a subsea production control
system.
12. The system of claim 1 wherein the water bottom multiplexer
includes a communication interface coupled between the multiplexer
and at least one of the remote devices.
13. The system of claim 1 wherein the water bottom communication
device comprises only one communication interface.
14. The system of claim 1 wherein the water bottom communication
device and the water surface communication device are configured to
operate with a proprietary communication protocol.
15. The system of claim 1 further comprising at least one of a data
acquisition system and a device control system in signal
communication with the water surface communication device, at least
one of a data acquisition system and a device control system
configured to selectively switch on and switch off operation of at
least one of the remote devices by generating a control signal
therefore.
16. The system of claim 1 wherein the subsea multiplexer is
configured to control the operating power of each individual
multiplexed device or sensor.
17. The system of claim 1 further comprising a stand-alone
communications device mounted proximate the seafloor and external
to the subsea production control system.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The invention relates generally to the field of devices used
to communicate signals between a wellbore or seafloor-based device
having production control equipment at the bottom of a body of
water and production facilities located at the water surface. More
particularly, the invention relates to signal multiplexing devices
that enable signals to and from a plurality of wellbore or
seafloor-based devices to communicate to the production facilities
using existing water bottom to water surface communication
channels.
[0005] 2. Background Art
[0006] U.S. Patent Application Publication No. 2004/0262008 A1
filed by Deans et al. and incorporated herein by reference
describes a system for communicating signals from a production
facility located at the surface of a body of water, such as a
floating production, storage and offloading facility ("FPSO") or a
floating production platform, for example, to and from a wellbore
drilled through subsurface formations below the bottom of the body
of water or to and from sensors and equipment located on the
seafloor. The wellbore includes various sensors and control devices
connected to a communication linking device disposed in a
"wellhead" system disposed near the water bottom. The seafloor
equipment can include various sensors mounted on seabed production
equipment disposed on the water bottom.
[0007] In some instances, it may be desirable to add sensors and/or
control devices to an existing wellbore or seafloor equipment, or
to be able to couple sensors and/or control devices from additional
wellbores or seafloor equipment to an existing communication link.
Such need could be addressed by adding an additional communication
channel. Such need could also be addressed by providing additional
interfacing devices between such additional sensors/controls and an
existing communication channel. The latter option has been made
less desirable by adoption of certain industry standard
communication configuration and protocol. The configuration and
protocol are described in, Intelligent Well Interface
Standardisation ("IWIS") Panel, published by OTM Consulting Ltd.,
44 Quarry Street, Guildford, Surrey GU1 3XQ, United Kingdom. The
adopted standards limit the number of device interfaces that may be
used in association with a communication channel. Other
communications standards include the subsea instrumentation
interface standardization ("SIIS") interface standard, also
published by OTM Consulting Ltd. and the subsea fibre optic
montoring group ("SeaFOM") standard for fiber optic subsea
equipment, also published by OTM Consulting Ltd.
[0008] It is desirable to provide additional control device and/or
sensor communication capacity to an existing water bottom to water
surface communication channel without increasing the number of
device interfaces.
SUMMARY OF THE INVENTION
[0009] A system for communicating between a surface facility and a
subsea production control system includes a communications device
proximate the water surface. The water surface communications
device has at least one communication interface. A communications
device is functionally associated with a wellhead or other
production control structure such as a production manifold
proximate the water bottom. The water bottom communications device
has at least one communication interface. A communication channel
extends between the surface communication device and the water
bottom communication device. A multiplexer is functionally coupled
to the communication interface on each of the surface and water
bottom communication devices. At least two remote devices are
functionally coupled to the water bottom multiplexer. The remote
devices are at least one of a sensor and a control. At least two
corresponding devices are coupled to the surface multiplexer. The
two corresponding devices include at least one of a signal
acquisition device and a control signal generating device.
[0010] Other aspects and advantages of the invention will be
apparent from the following description and the appended
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 shows an example arrangement of a subsea monitoring
and control (SMC) system that includes a multiplexing unit coupled
thereto.
[0012] FIG. 2 shows one example of a multiplexer coupled to a
subsea production control system.
[0013] FIG. 3 shows another example of a multiplexer coupled to a
subsea production control system.
[0014] FIG. 4 shows one example of equipment in a surface facility
that can send commands to an accept signals from
multiplexer-connected devices such as shown in FIGS. 2 and 3.
DETAILED DESCRIPTION
[0015] FIG. 1 shows an example arrangement of a subsea production
system, which includes a subsea well 10 in which certain types of
completion equipment is installed. The completion equipment
includes a production conduit 12, such as production tubing.
Various sensors 14, 16, 18 and control devices 20 are positioned
within the subsea well 10. Examples of sensors 14, 16, 18 include
pressure sensors, temperature sensors, flow rate sensors, shock
detectors (e.g., accelerometers), among other types of sensors.
Examples of control devices 20 include a flow control device (e.g.,
a valve) and a pump, among others. The sensors 14, 16, 18, and the
control device 20 can be coupled by a downhole communications link
22. The downhole communications link 22 can be an electrical cable,
a fiber optic line or a wireless communications link such as
acoustic or electromagnetic. The downhole communications link 22
extends to subsea wellhead equipment 24, such as a subsea well
control system or "tree." Part of the subsea wellhead equipment 24
can include a subsea production control system 26. Note that
sometimes the production control system may be mounted on a
structure such as a production manifold rather than on the tree and
perform valve control and monitoring on the seabed equipment rather
than in the wellbore ("downhole").
[0016] Other, various types of sensors and/or control devices 30
may be placed at or near the water bottom (sea bed), either in the
subsea wellhead equipment 24, at or within flow conduits arranged
on the seabed, on a hydrocarbon-gathering manifold, a
water-injection manifold, or elsewhere above or on the water bottom
but below the sea surface. The sensors and/or control devices 30
(collectively "water bottom devices") can include, as non-limiting
examples, a corrosion monitor, a sand monitor, a subsea flow meter,
a pump, a flow line measurement sensor, a seabed acoustic sensor, a
deposition sensor, a seabed seismic sensor. The various subsea
sensors and/or control devices 30 are also coupled to the subsea
production control system 26. Such sensors and/or control devices
can be coupled to the control system 26 using fiber optic
monitoring and control lines. For purposes of defining the sensors
can be interrogated or what control devices can be operated, the
term "remote device" is used herein to mean any device that
generates a signal either as indication of a change in status (such
as a control device being switched on or off) or in response to
detection of a physical parameter (a sensor), or any device that
changes its operation in response to a control signal (i.e., a
control device such as a valve being opened or closed or a pump
being switched on or off).
[0017] The subsea production control system 26 provides control
signals to the various subsea sensors and/or control devices and to
the various downhole sensors and/or control devices. The subsea
production control system 26 may also provide control signals to
wellhead equipment 24 components, such as valves. The subsea
production control system 26 may include a local processor (not
shown) that can generate such control signals in response to
parameters detected by one or more sensors (e.g., 14, 16, 18 and 30
in FIG. 1). The subsea production control system 26 may also accept
command signals generated by equipment (FIG. 4) on board the
surface facility and distribute such command signals to the various
control devices (e.g. 20 and 30 in FIG. 1).
[0018] In the present description a "subsea" device (such as a
subsea sensor or a subsea control device) refers to a device
located generally at or above the water bottom but below the sea
surface. A "downhole" device refers to a device placed in the well
10 or in another well drilled through the subsurface. More
generally, a "device" (such as a sensor or a control device)
associated with a subsea well refers to either a subsea device or a
downhole device.
[0019] In one example implementation, the subsea production control
system 26 is able to receive measurement signals from one or more
of the sensors associated with a subsea well for communication to a
surface facility 32 over a communications link 34. The
communications link 34 can be provided through a flexible
power/signal and/or produced fluid conduit called an "umbilical" 35
extending from the subsea wellhead equipment 24 to the surface
facility 32. Usually, hydraulic, electrical power and other control
lines are also provided through the umbilical 35. The subsea
production control system 26, as previously stated, may also accept
control signals from equipment (FIG. 4) disposed in the surface
facility 32 to control operation the various devices and to
communicate such control signals to the respective devices. The
surface facility 32 may be a production platform or a floating
production storage and offloading unit ("FPSO") or similar device
above the water surface that includes production monitoring and
control systems as well as equipment (not shown separately) to
process and direct the flow of fluids from one or more wells below
the water surface.
[0020] The communications link 34 can be implemented using
electrical cable, fiber optic lines, or, other types of
communications links such as acoustic telemetry through the water.
The subsea production control system 26 typically has a
communications interface that uses a proprietary communications
protocol for communicating signals between the subsea production
control system 26 and the equipment (FIG. 4) on the surface
facility 32. The proprietary protocol is typically specific to a
wellhead equipment manufacturer, and often differs between various
wellhead equipment manufacturers. In the present example, the
associated systems disposed in the wellhead equipment 24 and the
surface facility 32 can conform to a configuration and protocol
standard that is described in, Intelligent Well Interface
Standardisation ("IWIS") Panel, published by OTM Consulting Ltd.,
44 Quarry Street, Guildford, Surrey GU1 3XQ, United Kingdom, cited
in the Background section herein. The IWIS standard is set forth
in, ISO 13628 part 6:2006, published by the International
Organization for Standardization, ISO Central Secretariat, 1, ch.
de la Voie-Creuse, Case postale 56, CH-1211 Geneva 20,
Switzerland.
[0021] In the example arrangement shown in FIG. 1, the subsea
production control system 26 may only include a limited number of
interfaces for connection to various sensors and control devices
(shown at 14, 16, 18, 20 and 30 in FIG. 1), or may even include
only one such interface. In order to add additional sensors and/or
controls operable through the production control system 26 while
remaining in conformity with the above adopted industry standard, a
system according to the invention can include a communications
multiplexer 28 module (explained in more detail below with
reference to FIG. 2) to enable sharing the same communication
channel 34 for communication between additional subsea and/or
downhole sensors and/or controls with the surface facility 32. The
multiplexer module 28 may be disposed in the same housing as the
subsea production control system 26, or may be disposed in a
different housing.
[0022] One example of a multiplexer module 28 used with a subsea
production control system 26 is shown schematically in FIG. 2. The
subsea production control system 26 is shown as including a number
of existing power/sensor/control connections 36, each of which can
be used to supply operating power to, to supply control signals to
and to accept signals from a respectively coupled device such as
subsea sensors/controls 30, or the downhole devices the downhole
communications link 22. The existing connections 36 may be serial
(e.g., RS232, RS 422, RS485), Ethernet, or other industry standard
such as Profibus and Foundation Fieldbus, for example, or may be
proprietary. Because the number of such existing connections 36 is
limited, additional sensors and/or control devices (collectively
"devices") shown at 30A and which may include subsea devices and/or
downhole devices may be coupled over a communication line 29 to
only one of the existing connections 36 through the multiplexer
module 28. In the example shown in FIG. 2, the multiplexer module
28 may include a multiplexer card 42 disposed in a separate housing
and may include individual interface devices 44 for converting
proprietary communication protocol from each of the devices 30A
sent thereto over a communication line 33. The communication lines
33 may include both electrical power and signal communication
channels. The interface devices 44 are in signal communication with
the multiplexer card 42. Output of the multiplexer card 42 is
coupled to one of the existing connections 36 on the subsea
production control system 26.
[0023] In a different example shown in FIG. 3, the multiplexer
module 28 may only include the multiplexer card 42A, and may be
coupled to devices 30A that have open or industry standard
communication protocol (e.g., serial, Ethernet, Profibus,
Foundation Fieldbus, etc.) and/or interface devices directly
associated with each device, and thus do not require separate
interface devices in the module 28 such as shown in FIG. 2. The
devices 30A are coupled to the multiplexer 42A over communication
lines 31. The communication lines 31 may include both electrical
power and signal communication channels.
[0024] FIG. 4 shows one example of equipment located in the surface
facility 32 that can be used in connection with the
multiplexer-connected devices (30A) shown in FIGS. 2 and 3. A
surface acquisition system 48 is in signal communication with the
subsea production control system (26 in FIG. 1) over the
communication link or network 34. Signals communicated from the
various subsea and downhole devices are routed to the appropriate
destination device by the surface acquisition system 48 over
communication lines 51. Absent the multiplexer system of the
invention, the number of possible communication channels may be
limited by the particular configuration of surface acquisition
system and its corresponding communication connections in the
subsea production control system (26 in FIG. 1). Signals associated
with the various subsea and downhole devices (e.g., 14, 16, 18 and
30 in FIG. 1) are routed to their ordinary destination in data
storage and processing systems, shown generally at 50. Such systems
50 may include any and all surface facility devices associated with
processing measurements from subsea and/or downhole sensors, and
devices to send suitable control signals to operate such sensors
and/or control devices, as explained with reference to FIG. 1.
[0025] In the present example, multiplexed signals, originating
from the multiplexer (42 in FIG. 2 and 42A in FIG. 3), that occupy
a particular portion of the communication protocol used between the
surface acquisition system 48 and the production control system (26
in FIG. 1) are routed to a surface multiplexer 52. The surface
multiplexer 52 may be embodied as software running on personal
computer ("PC") hardware, or may be embodied, for example, as a
application specific integrated circuits (ASICs) on a dedicated or
other circuit board associated with the surface acquisition system
48. Signals corresponding to each of the multiplexed devices (30A
in FIGS. 2 and 3) are then demultiplexed and are routed to a
corresponding surface data acquisition or control operating device
54 over a communication line 53. In some implementations, one or
more of the surface devices 54 may communicate data and signals
directly to the data storage and processing system 50. The surface
data acquisition or control device 54 may be embodied as software
running on a separate PC or possibly the same PC as the surface
multiplexer 52. The communication protocol sent over the
communication lines 53 may be proprietary to the particular device
(30A in FIGS. 2 and 3), or may be a standard communication
protocol, e.g. serial, Ethernet, etc. The device 54 may be either
or both of a data acquisition device. Where the subsea or downhole
device (30A in FIG. 2) is a sensor, the surface device 54 would
typically include data acquisition elements. Where the subsea or
downhole device is a control device, such as a valve or pump, the
surface device 54 would typically include control signal generating
elements. The surface device 54 may include both acquisition and
control signal elements for combination devices subsea or
downhole.
[0026] A system according to the invention also relates to the
control, supply and monitoring of the electrical power to each
device interface card (44 in FIG. 2) and/or device (30A in FIGS. 2
and 3). The subsea production and control system 26 can provide
electrical power to the subsea multiplexer (42 in FIG. 2) over the
same subsea cable or jumper which contains the communication
channel (29 in FIG. 2). The subsea multiplexer module 28 can then
route power to each connected internal device interface card (44 in
FIG. 2) or to each external device (30A in FIGS. 2 and 3). The
subsea multiplexer 42 can switch the power on or off to each device
and provides monitoring of the individual power supplies to each
device. If the existing subsea production control system 26 cannot
provide sufficient power for the subsea multiplexer module and
sensors, power can be provided directly from surface to the subsea
multiplexer module 28 over the existing subsea infrastructure and
umbilical (35 in FIG. 1) or through a new umbilical and power
supply in the surface facility (32 in FIG. 1).
[0027] The surface multiplexer 52 packages the communications
message with a unique device identifier or address and sends it to
the surface acquisition system 48 for communication to the subsea
production control system (26 in FIG. I) over the communication
channel 34. The message is then delivered to the multiplexer module
(28 in FIGS. 2 and 3) over a local communication connection (29 in
FIGS. 2 and 3). The multiplexer (42 in FIG. 2 or 42A in FIG. 3)
retrieves the original communications message and sends it to the
appropriate interface card (44 in FIG. 2) over a communication link
using the device identifier in the message as a reference, or as
explained with reference to FIG. 3, directly to the respective
device. The response from the device or interface card is sent to
the surface by the reverse operation through the multiplexer (42 in
FIG. 2 or 42A in FIG. 3).
[0028] A multiplexing system according to the various aspects of
the invention may provide the capability of adding multiple
additional subsea and/or downhole devices to an existing subsea
production monitoring and control system without the need to modify
such system and without the need to add additional communication
channels between the wellhead equipment and the surface
facility.
[0029] While the invention has been described with respect to a
limited number of embodiments, those skilled in the art, having
benefit of this disclosure, will appreciate that other embodiments
can be devised which do not depart from the scope of the invention
as disclosed herein. Accordingly, the scope of the invention should
be limited only by the attached claims.
* * * * *