Control of Rotary Steerable Toolface in Directional Drilling

This paper presents a detailed mathematical model of a rotary steerable drilling system (RSS) that adopts hydro-electromechanical devices to generate bending torque in adjusting the toolface (TF). Key requirements of RSS are to adjust the TF promptly to track the TF command, to maintain the TF in presence of the external disturbances, and to do so during the drilling process. Accordingly, a controller with a fast response time and effective disturbance rejection capability is desired for the RSS. The complexity and non-linearities of the RSS creates additional challenges to the controller design. This paper describes a simple and effective controller scheme that is designed based on the analysis of the system’s dynamics model. By decoupling the disturbances, physical state feedback, and non-linearities, the RSS can be controlled by using a simple and effective proportional-integral-derivative (PID) controller with the desired performance. The simulation results show that the proposed controller is effective against the disturbance and the variations of the parameters.

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Extended State Observer Based Controller Design for the Green Bank Telescope Servo System

Volume 3: Multiagent Network Systems; Natural Gas and Heat Exchangers; Path Planning and Motion Control; Powertrain Systems; Rehab Robotics; Robot Manipulators; Rollover Prevention (AVS); Sensors and Actuators; Time Delay Systems; Tracking Control Systems; Uncertain Systems and Robustness; Unmanned, Ground and Surface Robotics; Vehicle Dynamics Control; Vibration and Control of Smart Structures/Mech Systems; Vibration Issues in Mechanical Systems ◽

10.1115/dscc2015-9677 ◽

2015 ◽

Cited By ~ 2

Author(s):

Trupti Ranka ◽

Mario Garcia-Sanz ◽

John M. Ford

Keyword(s):

Disturbance Rejection ◽

Pid Controller ◽

Controller Design ◽

Tracking Error ◽

State Observer ◽

Extended State Observer ◽

Tracking Performance ◽

Extended State ◽

External Disturbances ◽

Green Bank Telescope

The Green Bank Telescope is a large flexible structure, requiring rms tracking error ≤ 3 arcseconds against internal and external disturbances. We design an extended state observer (ESO) based controller in various configurations to improve tracking performance and increase disturbance rejection. The controllers are simulated with an experimentally validated model of the GBT. Through the simulations, the response of ESO based controllers and legacy PID controller are compared using time and frequency domain responses. We show that the ESO based controller when implemented in both position and velocity loop can give significant improvement in tracking performance and better disturbance rejection without increase in controller output.

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Control of Down-Hole Drilling Process Using a Computationally Efficient Dynamic Programming Method

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.4039787 ◽

2018 ◽

Vol 140 (10) ◽

Cited By ~ 4

Author(s):

Chong Ke ◽

Xingyong Song

Keyword(s):

Optimal Control ◽

Dynamic Programming ◽

Oil And Gas ◽

Dynamic Programming Method ◽

Hole Drilling ◽

Drilling Process ◽

Computationally Efficient ◽

Dynamics Model ◽

Control Optimization ◽

Drilling System

The unconventional down-hole resources such as shale oil and gas have gradually become a critical form of energy supply thanks to the recent petroleum technology advancement. Its economically viable and reliable production highly depends on the proper operation and control of the down-hole drilling system. The trend of deeper drilling in a complex environment requires a more effective and reliable control optimization scheme, either for predrilling planning or for online optimal control. Given the nonlinear nature of the drilling system, such an optimal control is not trivial. In this paper, we present a method based on dynamic programming (DP) that can lead to a computationally efficient drilling control optimization. A drilling dynamics model that can enable this method is first constructed, and the DP algorithm is customized so that much improved computational efficiency can be achieved compared with using standard DP. A higher-order dynamics model is then used to validate the effectiveness of the optimized control, and the control robustness is also evaluated by adding perturbations to the model. The results verify that the proposed approach is effective and efficient to solve the down-hole drilling control optimization problem.

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Optimizing Directional Drilling While Simultaneously Maximizing the Whole Life Value of the Well

10.2118/207342-ms ◽

2021 ◽

Author(s):

John Martin Clegg

Keyword(s):

Performance Indicator ◽

Production Equipment ◽

Drilling Process ◽

Directional Drilling ◽

Time Curve ◽

Rate Of Penetration ◽

Drilling Parameters ◽

Drilling System ◽

The Impact

Abstract Increasingly complex wells and longer laterals present new challenges for wellbore placement and wellbore quality. There is a growing understanding of the impact of well placement and wellbore quality on the overall value of the well and on the economics of completions and production. This paper looks at how requirements have evolved and will evolve beyond simply "getting to TD" as quickly as possible and how emerging technologies can help. There is already an undercurrent of opinion that completions and production are sometimes compromised to maximize rate of penetration, but with some controversy about the exact value and how easy it is to attribute cause. This paper reviews how directional drilling practice has evolved over 100 years, and how the wellbore quality that results from the directional drilling process can be a driver for the overall value of the well. Specifically, it draws on a number of key references to examine how tortuosity doesn't just have an influence on drilling but also how it can adversely impact completions, reliability of production equipment and even production rates. The paper proposes that we consider the whole-life value of the well as a key performance indicator as we drill. It emphasises that we must cease to focus solely on rate of penetration and the depth-time curve. The paper shows, with examples, how modern directional drilling systems can address tortuosity and improve wellbore quality. It presents an unbiased view of the industry from an independent viewpoint, exploring how directional drilling has been partially automated over the years and examining the state of the art in current automated directional drilling systems. It proposes the need for a modern directional drilling system not just in terms of drilling parameters but also in terms of automation of geometric and, ultimately, geologic aspects of directional drilling. The paper is intended to break down the silos that can exist between drilling, completions and production functions, and to help the industry to think about the long-term consequences of performance when specifying future directional drilling equipment.

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Adaptive Digital Disturbance Rejection Controller Design for Underwater Thermal Vehicles

Journal of Marine Science and Engineering ◽

10.3390/jmse9040406 ◽

2021 ◽

Vol 9 (4) ◽

pp. 406

Author(s):

Guohui Wang ◽

Yanan Yang ◽

Shuxin Wang

Keyword(s):

Disturbance Rejection ◽

Control Method ◽

Controller Design ◽

Least Squares Method ◽

Vertical Plane ◽

Estimation Method ◽

Plane Motion ◽

External Disturbances ◽

Control Approach ◽

Waves And Currents

Underwater thermal vehicles, as ocean observation tools, are frequently affected by environment disturbances such as waves and currents, which may cause degradation of the observation accuracy of the vehicles. Consequently, it is important to design a controller for a vehicle that can resist ocean disturbance. In this study, an underwater thermal vehicle principle is introduced, and the mathematical model is established in the vertical plane motion. On this basis, an adaptive digital disturbance suppression control method is proposed. For known disturbance parameters, this controller could compensate for external disturbances by pre-setting control parameters using the internal model principle and parameterizations method. For the case where the disturbance parameters are unknown, disturbance parameter estimation method based on forgetting factor least-squares method is proposed to transform the unknown parameter disturbance into a disturbance with known parameters, which is then suppressed by the adaptive digital disturbance rejection control approach. This solution could effectively solve the challenges caused by parameter uncertainty and unknown time-varying ocean external disturbances. Finally, simulations are carried out for the Petrel underwater thermal glider as an example. The simulation results show the proposed control method’s superiority and inherent robustness.

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Simulation on Active Disturbance Rejection Control

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.391.420 ◽

2013 ◽

Vol 391 ◽

pp. 420-423

Author(s):

Wei Zhang ◽

Ying Bo Cai ◽

Xue Tong Wei

Keyword(s):

Disturbance Rejection ◽

Controller Design ◽

Error Feedback ◽

External Disturbances ◽

Tracking Differentiator ◽

Active Disturbance Rejection ◽

Feedback Path ◽

Disturbance Rejection Control ◽

Excellent Control ◽

Nonlinear State

A highly robust active disturbance rejection controller (ADRC) is developed in this paper. The proposed ADRC consists of a tracking differentiator (TD) in the feed forward path, an extended state observer (ESO), and a nonlinear state error feedback control law (NLSEF) in the feedback path. The control theory, the structure of ADRC and the controller design are presented. LabVIEW is used for modeling, simulation and analysis of the dynamic system. Simulation results show that the proposed ADRC has excellent control performance, especially outstanding adaptability and robustness external disturbances and model uncertainties.

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