A downhole power generation system is disclosed, which includes a turbine generator system. The turbine generator system includes a turbine, a generator coupled with the turbine and having an AC-DC rectifier, and an optimized power control unit. The turbine is driven by flow of a downhole fluid to rotate. The generator converts rotational energy from the turbine to electrical energy and outputting a direct current voltage. The turbine generator system is coupled to a load via the optimized power control unit. The optimized power control unit controls to regulate an output voltage of the generator and provides a regulated output voltage to the load so that the turbine generator system has an optimized power output. An optimized power control method for a downhole power generation system is also disclosed.

A plurality of energy-generator pods, and methods of use, are provided along a rotatable tubular string extending downhole from surface into a wellbore. In embodiments, rotation of the tubular acts as a rotor of the pod and an outer component about the tubular, capable of relative rotation thereabout, forms the stator. The pod can also be equipped with bi-directional wireless electronic data communication including communication uphole to surface from sensors downhole, pod-to-pod, and down-hole communication to downhole tools. Pods can be fit to centralizers already employed for rotary tubular strings, the centralizer portion engaging the wellbore and remaining stationary relative to the rotating centralized tubular.

A plurality of energy-generator pods, and methods of use, are provided along a rotatable tubular string extending downhole from surface into a wellbore. In embodiments, rotation of the tubular acts as a rotor of the pod and an outer component about the tubular, capable of relative rotation thereabout, forms the stator. The pod can also be equipped with bi-directional wireless electronic data communication including communication uphole to surface from sensors downhole, pod-to-pod, and down-hole communication to downhole tools. Pods can be fit to centralizers already employed for rotary tubular strings, the centralizer portion engaging the wellbore and remaining stationary relative to the rotating centralized tubular.

Provided is a wellbore tractor and method for operating a well system. The wellbore tractor, in one aspect, includes a base member, and one or more turbines fixed to the base member for rotating the base member in a first rotational direction based upon a first direction of fluid flow. The wellbore tractor, according to this aspect, further includes one or more wellbore engaging devices radially extending from the base member, the one or more wellbore engaging devices contactable with a surface of a wellbore for displacing the base member and one or more turbines axially downhole as the one or more turbines rotate in the first rotational direction.

Provided is a wellbore tractor and method for operating a well system. The wellbore tractor, in one aspect, includes a base member, and one or more turbines fixed to the base member for rotating the base member in a first rotational direction based upon a first direction of fluid flow. The wellbore tractor, according to this aspect, further includes one or more wellbore engaging devices radially extending from the base member, the one or more wellbore engaging devices contactable with a surface of a wellbore for displacing the base member and one or more turbines axially downhole as the one or more turbines rotate in the first rotational direction.

A downhole system includes a drill string having a drilling fluid flow channel and at least one turbine alternator deployed in the flow channel. The turbine alternator is configured to convert flowing drilling fluid to electrical power. A voltage bus is configured to receive electrical power from the turbine alternator and at least one electrical motor is configured to receive electrical power from the voltage bus. An electronic controller is configured to provide active control of the turbine alternator via processing a desired speed of the electrical motor to generate a desired torque current and feeding the desired torque current forward to the turbine alternator. The turbine alternator is responsive to the desired torque current such that it modifies the electrical power provided to the voltage bus in response to the desired torque.

A downhole system includes a drill string having a drilling fluid flow channel and at least one turbine alternator deployed in the flow channel. The turbine alternator is configured to convert flowing drilling fluid to electrical power. A voltage bus is configured to receive electrical power from the turbine alternator and at least one electrical motor is configured to receive electrical power from the voltage bus. An electronic controller is configured to provide active control of the turbine alternator via processing a desired speed of the electrical motor to generate a desired torque current and feeding the desired torque current forward to the turbine alternator. The turbine alternator is responsive to the desired torque current such that it modifies the electrical power provided to the voltage bus in response to the desired torque.

A first method of configuring a surface of a component exposed to fluid flow includes forming a plurality of protrusions on a surface, the plurality of protrusions separated by a plurality of channels, and depositing a coating on the surface to increase a coefficient of friction of the surface, the coating formed of a diamond-like carbon and having a wrinkled texture. A second method of configuring a surface of a component exposed to fluid flow includes forming a plurality of protrusions on a surface, the plurality of protrusions separated by a plurality of channels, and forming a plurality of nanotubes on the surface.

A first method of configuring a surface of a component exposed to fluid flow includes forming a plurality of protrusions on a surface, the plurality of protrusions separated by a plurality of channels, and depositing a coating on the surface to increase a coefficient of friction of the surface, the coating formed of a diamond-like carbon and having a wrinkled texture. A second method of configuring a surface of a component exposed to fluid flow includes forming a plurality of protrusions on a surface, the plurality of protrusions separated by a plurality of channels, and forming a plurality of nanotubes on the surface.

The invention relates to a hydraulic motor (2), comprising a cylindrical motor housing (201) with a central cylindrical rotor (202) carrying longitudinal vanes (208), wherein the vanes (208) are provided at the outer surface of the rotor (202) in such a manner that they can protrude into an annular space between the housing (201) and the rotor (202) in order to create a circumferential driving force on the rotor, wherein the housing (201) comprises inwards pointing salient cams (210) on its inner surface, which separate the annular space between the housing (201) and the rotor (202) into several hydraulic chambers (211) with at least one inlet (212) and at least one outlet (213) for a hydraulic medium, and the vanes (208) can swing around a longitudinal axis that is mostly parallel to the rotation axis of the rotor (202) into the hydraulic chambers (211). The invention further relates to the use of such a hydraulic motor in a drilling system, and a drilling system with such a hydraulic motor.