An electric submersible pump (ESP) system can include a pump driven by an electric motor. As an example, an ESP system may be deployed in a well, for example, to pump fluid. Such an ESP system may be exposed to harsh environmental and operational conditions. Knowledge of such conditions may facilitate operation of an ESP system. Various technologies, techniques, etc. described herein pertain to sensing information germane to an ESP system and transmission of such sensed information.
An electric submersible pump system can include a shaft; a power cable connector; an electric motor configured to receive power via the power cable connector for rotatably driving the shaft; a pump operatively coupled to the shaft; a power unit for generating power via rotation of the shaft; a remote unit that includes at least one sensor for sensing information, wireless transmission circuitry for wireless transmission of sensed information and a power interface to receive power generated by the power unit; and a base unit that includes wireless reception circuitry for receipt of wireless transmission of sensed information from the remote unit and wired transmission circuitry operatively coupled to the power cable connector. A method can include sensing information using at least one sensor of a remote unit of an electric submersible pump system; transmitting the sensed information via wireless transmission circuitry of the remote unit; and receiving the sensed information via wireless reception circuitry of a base unit of the electric submersible pump system. Various other apparatuses, systems, methods, etc., are also disclosed.
This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.
Features and advantages of the described implementations can be more readily understood by reference to the following description taken in conjunction with the accompanying drawings.
The following description includes the best mode presently contemplated for practicing the described implementations. This description is not to be taken in a limiting sense, but rather is made merely for the purpose of describing the general principles of the implementations. The scope of the described implementations should be ascertained with reference to the issued claims.
As to the geologic environment 140, as shown in
Conditions in a geologic environment may be transient and/or persistent. Where equipment is placed within a geologic environment, longevity of the equipment can depend on characteristics of the environment and, for example, duration of use of the equipment as well as function of the equipment. Where equipment is to endure in an environment over an extended period of time, uncertainty may arise in one or more factors that could impact integrity or expected lifetime of the equipment. As an example, where a period of time may be of the order of decades, equipment that is intended to last for such a period of time may be constructed to endure conditions imposed thereon, whether imposed by an environment or environments and/or one or more functions of the equipment itself.
In the example of
As shown, the well 203 includes a wellhead that can include a choke (e.g., a choke valve). For example, the well 203 can include a choke valve to control various operations such as to reduce pressure of a fluid from high pressure in a closed wellbore to atmospheric pressure. A wellhead may include one or more sensors such as a temperature sensor, a pressure sensor, a solids sensor, etc.
As to the ESP 210, it is shown as including cables 211 (e.g., or a cable), a pump 212, gas handling features 213, a pump intake 214, a motor 215, one or more sensors 216 (e.g., temperature, pressure, strain, current leakage, vibration, etc.) and a protector 217.
As an example, an ESP may include a REDA™ Hotline high-temperature ESP motor. Such a motor may be suitable for implementation in a thermal recovery heavy oil production system, such as, for example, SAGD system or other steam-flooding system.
As an example, an ESP motor can include a three-phase squirrel cage with two-pole induction. As an example, an ESP motor may include steel stator laminations that can help focus magnetic forces on rotors, for example, to help reduce energy loss. As an example, stator windings can include copper and insulation.
As an example, the one or more sensors 216 of the ESP 210 may be part of a digital downhole monitoring system. For example, consider the commercially available Phoenix™ Multisensor xt150 system marketed by Schlumberger Limited (Houston, Tex.). A monitoring system may include a base unit that operatively couples to an ESP motor (see, e.g., the motor 215), for example, directly, via a motor-base crossover, etc. As an example, such a base unit (e.g., base gauge) may measure intake pressure, intake temperature, motor oil temperature, motor winding temperature, vibration, currently leakage, etc. As explained with respect to
As an example, a remote unit may be provided that may be located at a pump discharge (e.g., located at an end opposite the pump intake 214). As an example, a base unit and a remote unit may, in combination, measure intake and discharge pressures across a pump (see, e.g., the pump 212), for example, for analysis of a pump curve. As an example, alarms may be set for one or more parameters (e.g., measurements, parameters based on measurements, etc.).
Where a system includes a base unit and a remote unit, such as those of the Phoenix™ Multisensor x150 system, the units may be linked via wires. Such an arrangement provide power from the base unit to the remote unit and allows for communication between the base unit and the remote unit (e.g., at least transmission of information from the remote unit to the base unit). As an example, a remote unit is powered via a wired interface to a base unit such that one or more sensors of the remote unit can sense physical phenomena. In such an example, the remote unit can then transmit sensed information to the base unit, which, in turn, may transmit such information to a surface unit via a power cable configured to provide power to an ESP motor.
Where a remote unit and a base unit are coupled via wires, damage to the wires can result in loss of functionality of the remote unit. As an example, a system may be provided with wireless communication technology for at least transmission of information from a remote unit to a base unit (e.g., or to another remote unit). As an example, such wireless communication technology may be provided optionally in addition to one or more wires between a base unit and at least one remote unit. As an example, wireless communication technology may be selectable for use, used where a wire is damaged, etc.
As an example, a wireless remote ESP sensor unit may be installed in or on an ESP string to monitor one or more pump operational parameters (e.g., pressure, temperature, vibration, flow, shaft strain and torque, etc.) and transmit information wirelessly to a base unit and/or another remote unit. As an example, a remote unit may be powered by electrical energy generated from a rotating ESP shaft. As an example, a base unit may be deployed below an ESP motor and powered, for example, via a wye point connection. As an example, a remote unit may be integrated into one or more ESP components (e.g., a component housing, etc.), which may help minimize a number of on-site connections (e.g., and optionally maintain an outer profile of an ESP). As an example, a system may include an energy storage device such as, for example, a battery, a flywheel, one or more capacitors (e.g., optionally super-capacitors), etc. As an example, a storage device may be configured to provide power to at least a remote unit where an energy generation unit may generate insufficient energy (e.g., where an ESP shaft may be stationary).
As an example, where wireless technology is employed (e.g., for interoperation between a base unit and a remote unit), an ESP system may optionally be configured with a smaller overall system OD, simplified installation and improved reliability (e.g., because risk of physically damaging wires while RIH or operation may be avoided).
In the example of
In the example of
As shown in
In the example of
For FSD controllers, the UniConn™ motor controller can monitor ESP system three-phase currents, three-phase surface voltage, supply voltage and frequency, ESP spinning frequency and leg ground, power factor and motor load.
For VSD units, the UniConn™ motor controller can monitor VSD output current, ESP running current, VSD output voltage, supply voltage, VSD input and VSD output power, VSD output frequency, drive loading, motor load, three-phase ESP running current, three-phase VSD input or output voltage, ESP spinning frequency, and leg-ground.
In the example of
In the example of
As shown, the power cable 411 connects to a motor block 415, which may be a motor (or motors) of an ESP and be controllable via the VSD block 470. In the example of
As an example, power cables and MLEs that can resist damaging forces, whether mechanical, electrical or chemical, may help ensure proper operation of a motor, circuitry, sensors, etc.; noting that a faulty power cable (or MLE) can potentially damage a motor, circuitry, sensors, etc. Further, as mentioned, an ESP may be located several kilometers into a wellbore. Accordingly, time and cost to replace a faulty ESP, power cable, MLE, etc., can be substantial (e.g., time to withdraw, downtime for fluid pumping, time to insert, etc.).
As an example, the remote unit 580-1 may include a wireless module 581-1, a power interface 582-1 and a process module 583-1. As an example, the remote unit 580-2 may include a wireless module 581-2, a power interface 582-2 and a process module 583-2. In the example of
As an example, the unit control module 562 of the base unit 560 may include circuitry, processor executable instructions, etc. for performing control tasks associated with the one or more remote units 580-1 and 580-2. For example, the unit control module 562 may provide for arbitration of information transmission, which may include transmission of measured values, commands, etc. As an example, the unit control module 562 may arbitrate transmissions, for example, deciding when and/or how to transmit information to the process unit 530 (e.g., via an ESP motor power cable).
As an example, the unit control module 562 may monitor power status of the one or more remote units 580-1 and 580-2, for example, to determine a transmission schedule, a sensing schedule, etc. In such an example, where a remote unit may be low on power (e.g., due to lack of supply by a power unit, due to a power storage device being depleted, etc.), the unit control module 562 may reduce demand (e.g., load) of the remote unit. Further, where power level changes to a higher level, the unit control module 562 may adjust demand (e.g., load) of the remote unit. For example, where ample power is available, the unit control module 562 may call for more frequent sensing, more accurate sensing (e.g., more samples, higher bit depth, etc.).
As an example, the unit control module 562 may make decisions based at least in part on sensed information, whether from the base unit 560 or one or more of the one or more remote units 580-1 and 580-2. As an example, a remote unit may include unit control circuitry, for example, that may provide for control of one or more remote units. In such an example, a master remote unit may implement one or more control schemes for another remote unit (e.g., master-slave arrangement). As an example, a remote unit that is physically positioned closest to a base unit may be configured to be a master remote unit with respect to one or more other remote units that are physically positioned further away from the base unit. For example, the remote unit 580-1 may be a master remote unit while the remote unit 580-2 may be a slave remote unit. In such an example, transmission of information from the remote unit 580-2 may occur via the remote unit 580-1 (e.g., in daisy-chain manner). Such an approach may provide for increased signal-to-noise for transmission of information to and/or from the remote unit 580-2 (e.g., with respect to the base unit 560).
As to the wireless modules 581-1 and 581-2, the base unit 560 may include corresponding circuitry. As an example, wireless transmission may occur according to a wireless transmission standard. As an example, wireless transmission may occur via a medium or media that is in an annular space between an ESP system and a wall (e.g., of completion equipment, tubing, a borehole, etc.). While
As an example, a system may provide for monitoring operational parameters of an ESP system in multiple points along an ESP system string. As shown in the example of
As an example, a remote unit (e.g., a remote sensor unit) may include an associated power generation unit and a wireless communication module, for example, in to sensor electronics. Such a remote unit may be implemented, for example, without a dedicated cable(s), connector(s), etc. to a base unit. In such an example, a base unit may include a communication module to receive/transmit data from/to the remote unit. As an example, a base unit may be configured with circuitry to communicate bi-directionally and optionally simultaneously (e.g., using multiplexing technology or other technology) with a number of remote units. As an example, a system may include a remote unit installed between each pump section in an installation that includes multiple pump sections.
As an example, frequency division multiplexing, time division multiplexing and/or other multiplexing may optionally be implemented for transfer of information between units. As an example, code division multiplexing may be implemented. As an example, wireless communication may be implemented using analog and/or digital communication technologies. As an example, modulation may be employed for transmission of information and, for example, demodulation may be employed for receipt of information. As an example, modulation may include one or more of analog and digital modulation. As an example, modulation may include varying one or more properties of a waveform (e.g., a carrier signal) using a modulating signal or signals. As an example, information may be represented as a modulated signal or signals, which, in turn, may be demodulated. As an example, communication circuitry (e.g., a communication module) may include a signal generator and modulation circuitry to module a generated signal and/or demodulation circuitry. As an example, communication circuitry may include one or more antennas, which may be configured for transmission and/or receipt of signals.
As an example, communication circuitry may be configured for communication in a radio frequency (RF) or other frequency band or bands. As an example, circuitry may be provided that may adjust a communication technique, for example, via mode switching, etc. For example, circuitry may determine quality (quality of signal) and implement an algorithm to determine whether quality may be improved. Where quality may be improved, for example, by a desirable amount, such circuitry may adjust one or more communication parameters (e.g., carrier frequency, etc.). Such an approach may be implemented, for example, where a medium or media through which a signal is transmitted changes (e.g., consider media in an annular space about an ESP). As an example, a method may include one or more of hopping and shifting, for example, to maintain a communication link and/or to improve a communication link. As an example, a sensor or sensors may sense one or more characteristics of a medium or media (e.g., one or more dielectric properties). In such an example, sensed information may be used to maintain and/or improve communication (e.g., with respect to one or more remote units). As an example, circuitry may respond to one or more sensed condition, for example, as to intake and discharge of a pump or pumps, which may indicate that one or more characteristics of a medium or media in a region through which signals are carried may have changed, for example, which may impact signal quality. For example, consider a change as to one or more of gas content, water content, hydrocarbon content, etc. of media (e.g., multiphase media) through which signals are carried. In such an example, sensed information may be germane to ESP operation and/or to communication (e.g., quality of communication, etc.).
As an example, wireless technology may provide for transmission for a specified distance, for example, to provide for transmissions between units of a system in a particular environment. As an example, remote units may be “daisy-chained” wirelessly, for example, to amplify signal (e.g., with respect to noise) and transfer to/from adjacent remote units (e.g., to enhance reliability). As an example, bi-directional communication between a base unit and one or more remote units may provide for change of settings, different sampling rates and controlling other operational parameters of the one or more remote units.
As an example, one or more internal components of a remote unit may be packaged in a short pump housing with a flange and shaft connections, which may provide for a more simplified equipment design, for example, as to on-site connections, etc.
As an example, a power unit and a remote unit may utilize limited space, for example, internally in a housing and in a manner positioned as to minimize restriction to flow of produced fluid. As an example, a discharge remote unit (e.g., a remote unit including one or more sensors for sensing information at a discharge of a pump) may be configured with short shaft that extends to reach a power unit, which may, for example, maximize area for fluid flow. As an example, a bearing system may be included in a pump to support and stabilize a shaft inside a housing. In such an example, a power unit may be located adjacent to or proximate to the bearing system.
As an example, a power unit may be implemented that is configured to convert rotational energy of a shaft to electrical energy, for example, to power sensor electronics and communication module (e.g., of a remote unit). As an example, a brushless AC generator (e.g., an alternator) may be employed. As an example, an arrangement may include strong rare-earth magnets affixed to a shaft forming N and S poles and creating an AC signal in stationary coils affixed to the pump/sensor housing. In such an example, the resulting signal may be rectified and conditioned as appropriate to provide power to one or more electronic components (e.g., operational circuitry, storage device(s), etc.).
As an example, a power unit may include induction generator circuitry, which may operate without use of rare-earth magnets and, for example, provide for higher temperature ceiling. As an example, an induction generator may be configured as a “squirrel cage” and operated similar to an ESP motor but in a reverse manner as a generator.
As mentioned, a system may include a power storage device. For example, a power unit, a remote unit, a storage unit, etc. may include a battery, a capacitor (e.g., super capacitor), a compact flywheel (e.g., kinetic energy storage device), etc. Such a storage device may allow a remote unit to operate for a period of time after an ESP is switched off and the shaft is not rotating. For example, where power drops below a level for reliable transmission, sensed information may still be acquired and stored in memory (e.g., NVRAM, etc.) internal to a remote unit, for example, for transmission when an appropriate level of power becomes available.
As an example, a power unit may be configured such that rotational movement can be harvested directly from a shaft via a generator rotor (e.g., permanent magnet, squirrel cage, etc.) mechanically attached to the shaft. As an example, a shaft may be hydraulically coupled to a generator rotor via an intermediate low-drag fluid coupler (e.g., a hydraulic power unit). As an example, a hydraulic power unit may optionally be positioned within motor oil (e.g., in a protector or in a motor). As an example, a power unit (e.g., electrical alternator or inductor) may be located at or proximate to an end of a shaft. Such an approach may facilitate better tolerance of rotational speed transients (e.g., start, stops, rpm changes) for smoother operation. As an example, a fluid coupling may allow for implementation of a flywheel for power storage (e.g., kinetic energy storage). As an example, piezo-electric energy harvesting circuitry may be implemented, for example, a piezoceramic transducer may be stressed mechanically by a force (e.g., due to a component, fluid flow, fluid pressure, etc.) such that its electrodes receive a charge that tends to counteract imposed strain. In such an example, the charge may be, for example, collected, stored and/or delivered to power electrical circuitry.
As to the pump section 750, it includes a housing 751, a shaft 752, a communications module 753, a sensor module 754 operatively coupled to the communications module 753, and a power generation module 755 that can generate power via rotation of the shaft 752. As shown, the shaft 752 includes a coupling 757 and a coupling 759. As an example, the pump section 750 may be an intermediate pump section that may be disposed adjacent to another pump section or that may be disposed between two pump sections. For example, the coupling 757 may couple to a pump section such as the pump section 740 and the coupling 759 may couple to a protector or another pump section (e.g., such as the pump section 750).
As an example, a system may include one or more of the pump sections 740 and 750. As an example, a system may include the pump section 740 mounted to the pump section 750 where, for example, a motor may drive the shaft 742 via the shaft 752. In such an example, a protector may be mounted between the motor and the pump section 750.
As an example, a system may include multiple pump sections where each of the pump sections includes a communications module. In such a system, the communications modules may be daisy-chained. For example, a communications module of a terminal pump section may communicate with a communications module of an intermediate pump section, which may, in turn, communicate with a communications module of a base unit (e.g., a gauge), which may be mounted to a motor section. In the example of
As an example, a terminal pump section may be an uppermost pump section that may include a sensor for sensing information such as, for example, discharge pressure and optionally one or more other physical phenomena (e.g., temperature, flow rate, etc.). Such information may be communicated to a base unit (e.g., a gauge), directly or indirectly, where, for example, it may be analyzed in conjunction with other sensed information (e.g., intake pressure, etc.).
As an example, a remote unit that includes a sensor may also include a generation module. For example, a remote unit may include circuitry, components, etc. of a power unit such as, for example, the power unit 890.
In the example of
As an example, a fluid coupling can include two toroids in a sealed shell of fluid (e.g., substantially incompressible fluid) where one of the toroids is attached to a driving shaft and spins with rotational force such that the spinning toroid moves the fluid around the receiving toroid. In such an example, movement of the fluid can turn the receiving toroid and thus turn the connected shaft.
As an example, a power unit or power generation module may include a fluid coupling, for example, as a hydrodynamic device to transmit rotating mechanical power to drive a generator (e.g., coupled to a driven shaft). As an example, a fluid coupling may provide for variable speed operation and/or controlled start-up with reduced shock loading.
As an example, an electric submersible pump system can include a shaft; a power cable connector; an electric motor configured to receive power via the power cable connector for rotatably driving the shaft; a pump operatively coupled to the shaft; a power unit for generating power via rotation of the shaft; a remote unit that includes at least one sensor for sensing information, wireless transmission circuitry for wireless transmission of sensed information and a power interface to receive power generated by the power unit; and a base unit that includes wireless reception circuitry for receipt of wireless transmission of sensed information from the remote unit and wired transmission circuitry operatively coupled to the power cable connector. Such a system may include one or more additional remote units, for example, where each remote unit includes at least one sensor for sensing information and wireless transmission circuitry for wireless transmission of sensed information.
As an example, a remote unit may include wireless reception circuitry for wireless receipt of information and wireless transmission circuitry for wireless transmission of sensed information. As an example, a remote unit may include wireless reception circuitry for wireless receipt of information from another remote unit.
As an example, a remote unit can include wireless reception circuitry for wireless receipt of a remote unit control command, for example, where a base unit includes wireless transmission circuitry for wireless transmission of the remote unit control command. As an example, a daisy-chain of remote units may be provided for transmission of a command from a base unit to one of the remote units.
As an example, a system may include multiple sections where each of at least two of the sections includes a remote unit. In such an example, the multiple sections may include multiple pump sections. For example, a system may include multiple pump sections where each pump section includes a remote unit that includes at least one sensor for sensing information, wireless transmission circuitry for wireless transmission of sensed information and a power interface to receive power generated by a power unit, which may optionally be part of the remote unit.
As an example, a power unit can include a stator and a rotor where the rotor is operatively coupled to a shaft of an ESP system. As an example, a power unit can include a fluid coupling for moving fluid where the fluid coupling is operatively coupled to a shaft of an ESP system.
As an example, an ESP system may include a power storage device operatively coupled to at least a power interface of a remote unit. In such an example, the power storage device may be operatively coupled to a power unit. As an example, a power storage device may be or include one or more of a battery, a capacitor and a kinetic energy storage device.
As an example, an ESP system may include an electric motor that is a multiphase motor with a wye point where a base unit includes power reception circuitry operatively coupled to the wye point. In such an example, wired transmission circuitry of the base unit (e.g., wired communication circuitry) may be operatively coupled to a power cable connector via the wye point (e.g., for transmission and/or receipt of information via one or more conductors of the power cable).
As an example, an ESP system may be arranged as a string where a base unit is positioned at an end of the string and where the base unit is operatively coupled to an end of an electric motor. In such an example, a remote unit may be positioned at least in part within a pump housing of a pump of the ESP system. As an example, a remote unit may include a sensor for sensing information associated with a pump intake or a sensor for sensing information associated with a pump discharge.
As an example, a shaft of an ESP system may include multiple portions and a power unit may include a coupling for coupling a first portion of the shaft to a second portion of the shaft.
As an example, a method can include providing an electric submersible pump system that includes a shaft, a power cable connector, an electric motor configured to receive power via the power cable connector for rotatably driving the shaft, a pump operatively coupled to the shaft, a power unit for generating power via rotation of the shaft, a remote unit that includes at least one sensor for sensing information, wireless transmission circuitry for wireless transmission of sensed information and a power interface to receive power generated by the power unit, and a base unit that includes wireless reception circuitry for receipt of wireless transmission of sensed information from the remote unit and wired transmission circuitry operatively coupled to the power cable connector; sensing information using the at least one sensor of the remote unit; transmitting the sensed information via the wireless transmission circuitry; and receiving the sensed information via the wireless reception circuitry. As an example, such a method may include transmitting information based at least in part on the sensed information via the wired transmission circuitry.
As an example, one or more methods described herein may include associated computer-readable storage media (CRM) blocks. Such blocks can include instructions suitable for execution by one or more processors (or cores) to instruct a computing device or system to perform one or more actions. As an example, a computer-readable storage medium may not be a carrier wave (e.g., it may be a physical storage device).
According to an embodiment, one or more computer-readable media may include computer-executable instructions to instruct a computing system to output information for controlling a process. For example, such instructions may provide for output to sensing process, an injection process, drilling process, an extraction process, an extrusion process, a pumping process, a heating process, etc.
According to an embodiment, components may be distributed, such as in the network system 1010. The network system 1010 includes components 1022-1, 1022-2, 1022-3, . . . 1022-N. For example, the components 1022-1 may include the processor(s) 1002 while the component(s) 1022-3 may include memory accessible by the processor(s) 1002. Further, the component(s) 1002-2 may include an I/O device for display and optionally interaction with a method. The network may be or include the Internet, an intranet, a cellular network, a satellite network, etc.
Conclusion
Although only a few examples have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the examples. Accordingly, all such modifications are intended to be included within the scope of this disclosure as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures. It is the express intention of the applicant not to invoke 35 U.S.C. §112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the words “means for” together with an associated function.
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Number | Date | Country | |
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20150211526 A1 | Jul 2015 | US |