Abstract: A system and method of controlling a dynamic time-pressure profile associated with a perforation event that includes extending a perforation assembly within a casing string; firing a perforation gun of the perforation assembly; measuring, using a sensor of the perforation assembly, pressure within the casing string, wherein the measured pressure forms the dynamic time-pressure profile; identifying a first measured pressure within the dynamic time-pressure profile; identifying, using a controller of the perforation assembly, a first difference between the first measured pressure and a first reference pressure; and adjusting, using a first pressure generator of the perforation assembly, the pressure in response to the first difference to control the dynamic time-pressure profile; wherein the sensor, the controller, and the first pressure generator provide a feedback control loop.

Abstract: A downhole-type tool includes a casing joint, a housing affixed to the casing joint, and an electric stator encased in the housing. The housing defines an inner bore and has an inner bore wall that is continuous with an inner wall of the casing joint. The housing is sealed against ingress of cement to the stator. The electric stator is configured to drive an electric rotor-impeller. A flow of cement can be received with an outer surface of the housing. The flow of cement can be directed into an annulus between the housing and a wall of a wellbore. The casing joint can be cemented in the wellbore.

Abstract: A parameter of a magnetic bearing supporting a rotor in operation within a stator of the downhole-type rotating machine is measured. A speed of the rotor is controlled based on the measured parameter.

Abstract: A downhole-type system includes a rotatable rotor, a magnetic thrust bearing coupled to the rotor, and a mechanical thrust bearing coupled to the rotor. The magnetic thrust bearing is configured to support a first portion of an axial load of the rotor during rotor rotation, and the mechanical thrust bearing is configured to support a second portion of the axial load of the rotor during rotor rotation.

Abstract: Certain aspects of the subject matter described here can be implemented in a downhole-type electric submersible pump system. An electric machine can be disposed downhole in a wellbore. The electric machine is coupled to rotate with an impeller that can be disposed downhole in the wellbore. The electric machine includes a stator assembly with at least three stator sections axially arranged and spaced apart from each other along a longitudinal axis of the electric machine. The electric machine also includes a rotor assembly with at least three rotor sections arranged axially along the longitudinal axis of the electric machine. The rotor assembly is carried within and supported to rotate by the stator assembly.

Abstract: A stator assembly for a downhole-type well tool includes a stator housing including an internal chamber, an electric stator, a flow channel in the stator housing, and a heat exchanger. The electrical stator is disposed within the stator housing and in contact with the heat exchanger, the electrical stator to drive a rotor. The flow channel in the stator housing includes an inlet and an outlet, and the heat exchanger includes a first heat exchanger portion in contact with the electric stator in the internal chamber and a second heat exchanger portion at least partially disposed in the flow channel. The flow channel flows coolant fluid along the second heat exchanger portion to transmit heat across the heat exchanger from the electric stator to the coolant fluid.

Abstract: A fluid rotor is configured to move or be rotated by a working fluid. A fluid stator surrounds the fluid rotor. The fluid stator is spaced from the fluid rotor and defines a first annular fluid gap in-between that is in fluid communication with an outside environment exterior the downhole-type pump. A radial magnetic bearing includes a first portion coupled to the fluid rotor and a second portion coupled to the fluid stator. The first portion is spaced from the second portion defining a second annular fluid gap in-between that is in fluid communication with the outside environment exterior the downhole-type pump.

Abstract: An electric submersible pump (ESP) is described. The ESP includes a stator chamber, a stator within the stator chamber, a rotor, and an electrical connection. The stator chamber is configured to reside in a wellbore. The stator chamber is configured to attach to a tubing of a well. The stator chamber defines an inner bore having an inner bore wall that, when the stator chamber is attached to the tubing, is continuous with an inner wall of the tubing. The rotor is positioned within the inner bore of the stator chamber. The rotor includes an impeller. The rotor is configured to be retrievable from the well while the stator remains in the well. The stator is configured to drive the rotor to rotate the impeller and induce well fluid flow in response to receiving power through the electrical connection.

Abstract: A system includes a retrievable string for use in a completion string of a well, the completion string including an electrical stator. The retrievable string is to be disposed in the completion string, the retrievable string including a rotor for receipt within the electrical stator and to rotate in response to electromagnetic fields generated by the stator, an impeller coupled to the rotor, a housing to surround the impeller, and a recirculation isolator coupled to the housing. The recirculation isolator includes a sealing element and a locking tool, where the sealing element sealingly engages with the completion string, and the locking tool positions the retrievable string in the completion string and detachably couples the retrievable string to the completion string. The locking tool includes a rotational locking feature to engage an indexing receptacle of the completion string.

Abstract: A system to provide power to a downhole-type tool includes a downhole-type electric motor that can be positioned in a wellbore and a variable speed drive electrically connected to the electric motor, in which the downhole-type electric motor can operate at rotary speeds of at least 6,000 rotations per minute (rpm), the variable speed drive can control and supply power to the electric motor when the electric motor is positioned at a downhole location inside the wellbore, and the variable speed drive can be at a surface of the wellbore.

Abstract: A retrievable string configured to be positioned in a well is described. The retrievable string includes a rotating portion and a non-rotating portion. The rotating portion includes a rotor configured to be positioned in and driven by a stator of a well completion. The rotating portion includes an impeller coupled to the rotor. The non-rotating portion is cooperatively configured with the impeller to induce fluid flow in the well in response to the stator driving the rotor. The non-rotating portion includes a coupling part configured to support the rotor positioned in the stator. The coupling part is configured to detachably couple to a corresponding coupling part of the well completion.

Abstract: A gas flow velocity within a horizontal wellbore section is increased by a velocity string and a downhole-type compressor. A pressure within the horizontal wellbore section is decreased by a downhole-type compressor located within a vertical wellbore section fluidically connected to the horizontal wellbore section. Liquid build-up within the horizontal wellbore section is decreased in response to the increased gas flow velocity and the decreased pressure.

Abstract: A first electric stator surrounds a first electric rotor and is configured to cause the first electric rotor to rotate or generate electricity in the first electric stator when the first electric rotor rotates. The first electric stator includes a first set of electric windings. A second electric stator surrounds the second electric rotor and is configured to cause the second electric rotor to rotate or generate electricity in the second electric stator when the second electric rotor rotates. The second electric stator includes a second set of electric windings. The second electric stator is electrically coupled to the first electric stator. A controller is electrically coupled to both the first electric stator and the second electric stator. The controller is configured to exchange an electric current with a combination of the first electric stator and the second electric stator.

Abstract: A fluid module includes a fluid rotor configured to rotatably drive or be driven by fluid produced from a wellbore. A first shaft is coupled to the fluid rotor. The first shaft is configured to rotate in unison with the fluid rotor. A thrust bearing module includes a thrust bearing rotor. A second shaft is coupled to the thrust bearing rotor. The second shaft is configured to rotate in unison with the thrust bearing rotor. The second shaft is coupled to the first shaft. An electric machine module includes an electric machine rotor. A third shaft is coupled to the electric machine rotor. A third shaft is configured to rotate in unison with the electric machine rotor. The third shaft is coupled to the second shaft. The third shaft is rotodynamically isolated from the first shaft and the second shaft.

Abstract: A retrievable string is positioned in a stator of a completion string installed in a well. The retrievable string includes a rotating portion and a non-rotating portion. The rotating portion includes a rotor and an impeller coupled to the rotor. The non-rotating portion includes a coupling part. The coupling part is coupled to a corresponding coupling part of the completion string.

Abstract: A system for use in a completion string of a well is described. The system includes a coupling part configured to detachably couple a retrievable string to the system. The system includes a stator configured to attach to a tubing of the completion string. While the retrievable string is coupled to the system, the stator is configured to drive a rotor of the retrievable string in response to receiving power.

Abstract: A fluid module includes a fluid rotor configured to rotatably drive or be driven by fluid produced from a wellbore. A first shaft is coupled to the fluid rotor. The first shaft is configured to rotate in unison with the fluid rotor. A thrust bearing module includes a thrust bearing rotor. A second shaft is coupled to the thrust bearing rotor. The second shaft is configured to rotate in unison with the thrust bearing rotor. The second shaft is coupled to the first shaft. An electric machine module includes an electric machine rotor. A third shaft is coupled to the electric machine rotor. A third shaft is configured to rotate in unison with the electric machine rotor. The third shaft is coupled to the second shaft. The third shaft is rotodynamically isolated from the first shaft and the second shaft.

Abstract: A system to provide power to a downhole-type tool includes a downhole-type electric motor that can be positioned in a wellbore and a variable speed drive electrically connected to the electric motor, in which the downhole-type electric motor can operate at rotary speeds of at least 6,000 rotations per minute (rpm), the variable speed drive can control and supply power to the electric motor when the electric motor is positioned at a downhole location inside the wellbore, and the variable speed drive can be at a surface of the wellbore.

Abstract: A fluid rotor is configured to move or be rotated by a working fluid. A fluid stator surrounds the fluid rotor. The fluid stator is spaced from the fluid rotor and defines a first annular fluid gap in-between that is in fluid communication with an outside environment exterior the downhole-type pump. A radial magnetic bearing includes a first portion coupled to the fluid rotor and a second portion coupled to the fluid stator. The first portion is spaced from the second portion defining a second annular fluid gap in-between that is in fluid communication with the outside environment exterior the downhole-type pump.

Abstract: A downhole-type system includes a rotatable rotor, a magnetic thrust bearing coupled to the rotor, and a mechanical thrust bearing coupled to the rotor. The magnetic thrust bearing is configured to support a first portion of an axial load of the rotor during rotor rotation, and the mechanical thrust bearing is configured to support a second portion of the axial load of the rotor during rotor rotation.