Modelling and control of the roll-stabilised control unit of a rotary steerable system directional drilling tool

Hamid Alturbeh, James F. Whidborne, Patrick Luk, Martin Bayliss

Research output: Contribution to journalConference articlepeer-review


A directional drilling tool control unit whose design is based on servo control of a rotary valve using the roll-stabilised instrumented system approach has been successfully used in oil fields for over twenty years. In this paper, Field Oriented Control (FOC) is applied to cascaded voltage regulation and servo control using a open-loop plant model of the roll-stabilised control unit. The servo control is applied to the rotary valve so that drilling mud is ported in a geostationary direction despite the rotation of the drill string and the bottom hole assembly of the rotary steerable system. Voltage regulation is applied in order to provide a dc voltage bus for the servo control of the valve. A torquer or alternator, which is a type of permanent magnet synchronous machine, is the core of the roll stabilised control unit. So, a mathematical model of the torquer is derived. An FOC scheme is proposed for servo control and to provide a dc regulated voltage using the torquers. The algorithm is tested in MATLAB/Simulink.
Original languageEnglish
Pages (from-to)4555-4559
Number of pages5
JournalJournal of Engineering
Issue number17
Early online date26 Apr 2019
Publication statusPublished - 1 Jun 2019
Event9th International Conference on Power Electronics, Machines and Drives - Liverpool ACC, Liverpool, United Kingdom
Duration: 17 Apr 201819 Apr 2018
Conference number: 9 (Link to Conference Details)


Dive into the research topics of 'Modelling and control of the roll-stabilised control unit of a rotary steerable system directional drilling tool'. Together they form a unique fingerprint.
  • Rotary steerable roll stabilized control system

    Alturbeh, H., Whidborne, J. F. & Bayliss, M., 9 Mar 2017, Patent No. US 20170067332 A1, Priority date 3 Sep 2015, Priority No. US201615246769 20160825

    Research output: Patent

    Open Access

Cite this