Patent Application
20190071962
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the presently described embodiments. 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 embodiments. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
In order to meet consumer and industrial demand for natural resources, companies often invest significant amounts of time and money in finding and extracting oil, natural gas, and other subterranean resources from the earth. Particularly, once a desired subterranean resource such as oil or natural gas is discovered, drilling and production systems are often employed to access and extract the resource. These systems may be located onshore or offshore depending on the location of a desired resource.
Further, such systems generally include a wellhead assembly mounted on a well through which the resource is accessed or extracted. These wellhead assemblies may include a wide variety of components, such as spools, hangers, blowout preventers, and trees, that facilitate drilling or production operations. In offshore systems, risers are often used to couple the wellhead assembly to a platform or vessel at the surface of the water. Sensors are used in drilling and production systems to acquire data, and various cables can be used to provide operating power to the sensors.
Certain aspects of some embodiments disclosed herein are set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of certain forms the invention might take and that these aspects are not intended to limit the scope of the invention. Indeed, the invention may encompass a variety of aspects that may not be set forth below.
Embodiments of the present disclosure generally relate to power systems that use acoustic energy to provide operational power to electronic devices. In some instances, these power systems are used to facilitate operation of sensors or other electronic devices of a subsea installation, such as a well assembly. The power systems can include acoustic transmitters that radiate acoustic energy through seawater or another transmission medium to acoustic receivers that generate electric power in response to received acoustic energy. The generated electric power can be converted and used to power sensors directly, or to charge an energy storage device (e.g., a battery or a capacitor) from which the sensors draw power. Examples of sensors that can be powered in this manner include temperature sensors, pressure sensors, position sensors, flowmeters, and fluid-detection sensors, to name just several. In some embodiments, acoustic energy is used to generate operational power for sensors of marine risers, wellheads, blowout preventers, trees, other wellhead assembly equipment, pipelines, or abandoned wells.
Various refinements of the features noted above may exist in relation to various aspects of the present embodiments. 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. Again, the brief summary presented above is intended only to familiarize the reader with certain aspects and contexts of some embodiments without limitation to the claimed subject matter.
These and other features, aspects, and advantages of certain embodiments 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:
Specific embodiments of the present disclosure are described below. In an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
When introducing elements of various embodiments, the articles “a,” “an,” “the,” and “said” 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. Moreover, any use of “top,” “bottom,” “above,” “below,” other directional terms, and variations of these terms is made for convenience, but does not require any particular orientation of the components.
Turning now to the present figures, a well assembly or apparatus 10 is illustrated in
As will be appreciated, the drilling rig 14 can include surface equipment positioned over the water, such as pumps, power supplies, cable and hose reels, control units, a diverter, a gimbal, a spider, and the like. Similarly, the riser 16 may also include a variety of components, such as riser joints, flex joints, a telescoping joint, fill valves, and control units, to name but a few. The wellhead assembly 18 includes a wellhead 20 and equipment, such as blowout preventers, coupled to the wellhead 20 to enable the control of fluid from the well 12. Any suitable blowout preventers could be coupled to the wellhead 20, such as ram-type preventers and annular preventers. In at least some embodiments, the wellhead assembly 18 includes a lower marine riser package connected to a lower blowout preventer stack. And the wellhead 20 of the assembly 18 can also include various components, such as casing heads, tubing heads, spools, and hangers.
In this depicted embodiment, the apparatus 10 is a subsea well installation that includes sensors 24 for measuring parameters of interest. Such sensors 24 can include pressure sensors, temperature sensors, position sensors, or fluid-sensing devices, for instance. The sensors 24 are generally shown on the riser 16 and the wellhead assembly 18, but it will be appreciated that sensors 24 could also or instead be provided at other locations in the apparatus 10.
In at least some embodiments, the sensors 24 are operated with electric power generated from acoustic energy received through a body of water (e.g., a sea or ocean). More specifically, the apparatus 10 includes transmitters for radiating acoustic power, via acoustic waves, toward the sensors 24, and the body of water can be used as a transmission medium for the acoustic waves. Acoustic power may be transmitted to the sensors 24 from any suitable location.
The depicted apparatus 10, for example, includes a remotely operated vehicle (ROV) 26 connected to the drilling rig 14 via a tether 28, a buoy 30 at surface 32 of the water and connected to the drilling rig 14 with a tether 34, and a submersible 36 connected to the bed 38 (e.g., a seabed or ocean bed) by an anchor 40 and a tether 42. The ROV 26, the buoy 30, and the submersible 36 include acoustic transmitters for radiating acoustic waves 46 toward the sensors 24, and electric power for the acoustic transmitters is provided by the tethers 28, 34, and 42 in some embodiments. Acoustic transmitters may also or instead be provided elsewhere, such as on the drilling rig 14, on other equipment of the apparatus 10, or on an autonomous underwater vehicle. Acoustic receivers then receive the acoustic waves 46, which generate electrical signals that may be converted and used as operational power for the sensors 24. In at least some instances, the acoustic receivers are located on the riser 16 or the wellhead assembly 18 and generating operational power for the sensors from received acoustic energy enables omission of certain cabling or umbilicals that would otherwise be used to provide power to the sensors.
An example of a power transmission chain for transmitting acoustic energy and powering a sensor 24 is generally depicted in
The acoustic transmitters and receivers may take any suitable forms, such as ultrasonic transducers, other acoustic transducers, barrel stave projectors, ring projectors, planar (two-dimensional) transducer arrays, and cylindrical transducer arrays. In some embodiments, receiving transducers 54 are made with piezoelectric materials, such as lead zirconate titanate (PZT) (e.g., single element PZT-5A), lithium niobate, lead magnesium niobate-lead titanate (PMN-PT), or a piezoelectric composite.
Although a single transmitting transducer 52 could be used, a transducer array 64 is used to transmit acoustic waves 46 in at least some cases, as generally depicted in
In
Whether used as a single transmitting element or used as part of a transmitting array 64, a transducer 52 can also include an acoustic lens 68 to focus acoustic energy and form a narrow acoustic energy beam 70, as generally depicted in
Acoustic energy can be communicated via acoustic waves of any suitable frequency, such as sonic waves (20 Hz-20 kHz) or ultrasonic waves (above 20 kHz) In at least some embodiments, the acoustic energy is transmitted via acoustic waves 46 within a frequency range of 10 kHz-10 MHz. The frequency can be selected based on the distance from the transmitter (e.g., transducer 52 or transducer array 64) to the receiver connected to sensor 24. Electrical excitation waveforms from a signal generator to transmitting transducers can take various forms, such as sinusoidal or square waves that may be continuous or pulsed. The acoustic waveforms are pressure waves, which are plane waves or longitudinal waves, with a velocity of propagation specific to fluid density, bulk modulus, shear modulus, temperature, and pressure. Transmission loss can be calculated based on the spreading loss as a function of distance and attenuation of sound in the transmission medium (e.g., seawater). Because attenuation is a function of frequency, transmitting transducers can be operated from 1 meter to 10,000 meters in the frequency range from 10 MHz to 1 kHz in at least some instances. The amount of signal level generated depends on the radiated power of the transmitters and its directivity. In some embodiments, acoustic power output can range from 0.1 watts to 10,000 watts, thereby generating a source level of 160 dB to 230 dB. In cases of a transmitter using multiple transducers 52 (e.g., transducer array 64), the overall aperture size of the transmitter can be determined by arranging individual transducers 52 in parallel at low frequencies and power generated can be proportional to the overall area of the transmitter with the individual transducers 52.
Although acoustic energy can be used to provide operational power for sensors 24 of the riser 16 and equipment of the wellhead assembly 18 (e.g., blowout preventers), the present techniques may be used to power sensors in other systems and for different applications. As shown in
The acoustic energy received by the transducer 84 can be converted to electric power appropriate for the sensors 78, such as with an AC/DC converter and an amplifier as described above. The electric power may be provided directly to the sensors 78 or be used to charge a battery or other energy storage device from which the sensors 78 draw power. The transducers 84 and 86 can take any suitable form, such as the individual transducers or transducer arrays described above. Further, the resulting electric power can also be used to operate the acoustic modem 80 and allow data transmission. And while the pipeline 74 and the ship 76 are presently depicted with acoustic modems 80 and 82 distinct from the transducers 84 and 86, in other embodiments the transducers 84 and 86 could be used to communicate both power and data between the pipeline 74 and the ship 76.
In other embodiments, acoustic energy may be used to provide operational power to one or more sensors 78 that monitor an abandoned well, such as for potential leaking. As shown in
Although ships 76 are depicted along the surface 32 of the water in
In some embodiments, a vessel can travel to different subsea installations to provide acoustic power to and collect data from sensors of those installations. This may facilitate periodic monitoring of active or abandoned subsea wells, equipment, and pipelines. One such embodiment is depicted in
In this example, the vessel 100 travels along a route 102 toward each of the three depicted subsea installations. Once within a desired acoustic range of a subsea installation, the vessel 100 can convey acoustic energy to that subsea installation (e.g., from transducer 86), which can be received (e.g., at transducer 84) and converted to electric power used to operate sensors at the subsea installation, as described above. Data acquired with the sensors can be wirelessly communicated back to the vessel 100, such as with acoustic modems 80 and 82. The vessel 100 can then be moved toward additional subsea installations to provide acoustic power for operating sensors of those installations and to collect data from those sensors in similar fashion.
In at least one instance, the vessel 100 is an autonomous vehicle that can automatically (without human intervention): travel between the subsea installations along the route 102 (which may be a predetermined route), transmit acoustic energy to the subsea installations that can be used to provide operational power to sensors of the installations, and acquire data transmitted to the vessel 100 from the subsea installations. Although three subsea installations are depicted in
In at least some embodiments, such as any of the subsea embodiments described above, one or more sensor locating techniques may be used to facilitate transmission of acoustic energy toward sensors. In some examples, a homing signal can be generated from an acoustic modem 80, an acoustic transducer 54 or 84 that produces electric power for a sensor 24 or 78, or from an additional acoustic transducer that is near (e.g., connected in parallel with) the transducer 54 or 84. Such devices operable to send a homing signal may be referred to as a homing beacon, and the homing signal can be a transmitted pulse (e.g., a short pulse) that is received by the acoustic transducer 52 or 86 (or another nearby sensor) and used to determine a direction or location of the sensor 24 or 78 with respect to the acoustic transducer 52 or 86. A multidimensional transducer array, such as the array 64, can be operated to transmit acoustic energy to receiving transducers 52 or 86, as described above, but could also be operated as a receiving antenna to receive the homing signal (e.g., at vessel 100) and facilitate locating of the sensor. In some instances, the acoustic transducer 52 or 86 can be employed as a sonar system to locate the sensors subsea using a pulse echo approach and imaging, via echo location, or via an acoustic modem. In other embodiments, the positions of the components can be used to determine the direction in which the acoustic energy should be transmitted. For example, positions of the sensors and associated acoustic receivers can be stored (e.g., as coordinates of a three-dimensional rectangular or cylindrical coordinate system), the position of the acoustic transmitter can be determined (e.g., via a global positioning system), and the direction in which acoustic energy is focused can be determined based on the relative positions of the acoustic transmitter and the intended acoustic receiver.
In still other embodiments, acoustic energy is used to provide operational power for sensors installed inside drilling or production equipment (e.g., equipment of wellhead assembly 18), with the acoustic energy transmitted through a body of the equipment from an external acoustic transmitter to an acoustic receiver inside the body. An apparatus 106 is depicted in
In this embodiment, acoustic transmitters in the form of acoustic transducers 52 are provided on an exterior of the blowout preventer body 108, and these transducers 52 emit acoustic waves 46 through walls of the blowout preventer body 108 to acoustic receivers (e.g., transducers 54) within the body 108. The acoustic transducers 52 can be powered by electronics 116 (e.g., power supply and conditioning circuitry) via cables 118. In subsea environments, the cables 118 can be water block cables or pressure-balanced oil-filled (PBOF) cables. The acoustic receivers generate electric power from the received acoustic waves 46, which may be converted (via converters 56) and supplied to batteries 58 or sensors 24, as discussed above. In at least some embodiments, the transducers 52 and 54 are ultrasonic transducers. The sensors 24 within the blowout preventer body 108 could be used for various purposes, such as for measuring an environmental condition (e.g., pressure or temperature) within the blowout preventer, for detecting the position of the rams 110 or actuators 112, or for sensing or characterizing fluid within the blowout preventer. In other instances, a transducer 54 and a sensor 24 can be positioned inside a wellhead 20, the transducer 54 generates electric power from acoustic waves 46 received from the transducer 52 through the body of the wellhead 20, and this generated electric power is used for operating the sensor 24 (e.g., for measuring annulus pressure or temperature inside the wellhead 20).
While the aspects of the present disclosure may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. But it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.
