Schlumberger Technology Corporation

Ramakrishna Madhireddy

Jian Wu

Nathaniel Wicks

Seetharam Kothuru

Shyam Janakiraman

Franz Carstens

Brian McKinney

Wenshuai Hou

A motor controller to control rotational speed of an output shaft of an electric motor. The motor controller includes a proportional controller and a time-optimal controller. The proportional controller controls the rotational speed when a present rotational position of the shaft is between a target rotational position and a switching point, inclusively. The time-optimal controller controls the rotational speed when the present rotational position is not between the target rotational position and the switching point. Also introduced herein are aspects pertaining to determining the switching point in a manner that minimizes overshooting the target rotational position while maximizing expediency at which the target rotational position is reached.

Motor angular position control

Methods, apparatus, and products for receiving measurements indicative of present value torque (TrqPv) currently being applied by a top drive to a drill string extending in a well that penetrates a subterranean formation, and releasing torque accumulated in the drill string by determining polarity of TrqPv and, in response to a manual or automatic trigger, causing the top drive to perform an unwinding operation in a direction opposite to the determined TrqPv polarity.

Automatically detecting and unwinding accumulated drill string torque

Systems and methods for supplementing power to a drilling operation's generator and motor systems are disclosed. A power unit is connected to a power grid between generators and motors for a drilling operation. The power unit saps and stores energy from the electrical grid when the generator has excess capacity and providing power to the motors when the demand from the motors exceeds the available capacity of the generators.

Supplemental power unit for drilling rig

Methods and apparatus for including obtaining raw surface data for present values of torque (T) generated by a top drive operably coupled with a drillstring, obtaining raw surface data for present values of rotational speed (&#x3c9;) of the top drive corresponding to the T, obtaining inertia (J) of the top drive, and estimating torque Tof the drillstring based on the obtained Tdata, the obtained data, and the obtained Jdata. The estimated drillstring torque Tmay be utilized to determine a surface torque oscillation performance index (STOPI).

Estimating downhole RPM oscillations

Methods and apparatus for automatic, dynamically adjusted operation of load-sharing gensets. An example of such operation may include determining an updated genset-removal load based on a genset-addition load, an initial genset-removal load, a human-selected one of predetermined levels of dynamism, and the number of operating ones of the gensets. An operating genset is halted in response to the actual loads of each operating genset simultaneously being at or below the updated genset-removal load. In another example, while two or more gensets are operating, an updated genset-removal load is determined based on the genset-addition load and a hysteresis setpoint, and an operating genset is halted in response to actual loads of each operating genset simultaneously being at or below the updated genset-removal load.

Dynamic settings for genset automatic load-dependent start-stop control

Systems and methods for operating a series of generators configured to provide power to a motor or motors. Generators generally operate at different efficiency levels depending on the operating capacity. A computation component can analyze the current efficiency of the generators and determine if there is an alternative power distribution among the existing generators that would result in a more efficient operation of the system.

Load management algorithm for optimizing engine efficiency

Systems and methods for processing downhole rotational data. An example method includes commencing operation of a processing device to continually calculate a downhole oscillation index by receiving downhole rotational speed data indicative of downhole rotational speed of at least a portion of a drill string during drilling operations, calculating a fundamental oscillation time period of the drill string, calculating a time length of a time window based on the fundamental oscillation time period, and processing the downhole rotational speed data encompassed within the time window.

Processing downhole rotational data

Systems and methods for operating a motor according to parameters provided by an autotuning component if available are described. A controller can be coupled to a drive which operates a motor for executing a task that can be related to a drilling operation for oil and gas. The controller stores initial parameters and checks for new parameters provided by the autotuning component which are stored on the drive after the autotuning component autotunes the motor. If there are new parameters, they are given priority over the initial parameters.

Systems and methods for managing drive parameters after maintenance

Systems and methods for controlling a drilling rig are disclosed herein. A driller can select between modes: local, human-machine interface (HMI), and automatic. In a local mode a motor operator is instructed to operate a genset for the drilling rig. In a Remote mode the driller can operate the genset directly without the need for a motor operator to start or stop the gensets. In an automatic mode, the genset is controlled according to a well plan including a power consumption schedule.

Remote control and monitoring of engine control system

A system and method for drilling a wellbore with a drill rig by: rotating a drillstring and a drill bit with a drill rig drive system; applying a weight of the drillstring on the drill rig; measuring surface torque oscillations of the drill string via: determining a fundamental oscillation time period; select a time window based on the fundamental oscillation time period; collecting torque present value data of the drill string for the selected time window; determining an amplitude of torque oscillation from the collected torque present value data; determining a reference torque; and dividing the determined amplitude of torque oscillation by the determined reference torque to obtain a surface torque oscillation performance index, whereby the measurement of the surface torque oscillations of the drill string is a fractional value to indicate the magnitude and severity of surface torque fluctuations of the drilling string; and modifying a drilling parameter based on the surface torque oscillation performance index.

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Houston, TX, United States of America

Ramakrishna Madhireddy