MODELLING OF DYNAMIC POSITIONING SYSTEM OF AN OFFSHORE SHIP
https://doi.org/10.33815/2313-4763.2019.2.21.078-088
Abstract
The article discusses the modelling of the dynamic positioning system of a marine offshore vessel.
To meet the safety requirements when performing various special tasks at sea and to ensure proper and accurate control of the course and location of the offshore vessel, dynamic positioning systems (DP) are widely used.
The use of DP systems on ships of the marine offshore fleet is preferable from an economic point of view, since no additional costs are required to ensure effective control of the current location and course of the marine vessel during the performance of work.
The aim of the study is to develop a mathematical model of a dynamic positioning system for an offshore ship with four movers, which will determine the minimum power of the ship's electric power system. Models are necessary to ensure precision control when changing the characteristics of the power plant and reference systems in various situations.
The ship control system was modelled in a software environment using standard library modules, which were supplemented with the necessary data from an offshore ship. The issues of optimization of control systems and modelling methods were considered in the studies of Thor I. Fossen, Sorensen J.A. and Perez T. O.n. Smogeli taking into account the influence of external disturbances. In these studies, using modern control methods, a control object (vessel) in three-dimensional space is considered as an object with three or more degrees of freedom (DOF).
Given the variable values of external perturbations that affect the quality of control of an object, a significant role in controlling the DP system is played by the accuracy of forecasts and the speed of model updating. The simulation results allow us to describe an offshore vessel as a point of mass, taking into account three degrees of freedom, and we used the DP dynamic positioning system for heading analysis.
An analysis of the trajectory of an offshore vessel when modelling a dynamic positioning system made it possible to determine the minimum power of the ship's electric power system necessary for control. In the future, to model the control of an offshore vessel with a dynamic positioning system, modified models should be used, where more than five propulsions are used.
References
Vasil’yev A. V. (1989). Upravlyayemost’ sudov. Leningrad : Sudostroyeniye.
Gofman A. D. (1988). Dvizhitel’no-rulevoy kompleks i manevrirovaniye sudna. Spravochnik. Leningrad : Sudostroyeniye.
Shostak V. P. (2010). Dinamicheskoye pozitsionirovaniye plavuchikh ob»yektov : monografiya. Chikago : Megatron.
Vagushchenko L. L. & Tsymbal N. N. (2007). Sistemy avtomaticheskogo upravleniya dvizheniyem sudna. Odessa : Feniks.
Vagushchenko L. L. & Koshevoy A. A. (2000). Avtomatizirovannyye kompleksy sudovozhdeniya. Uchebnik dlya morskikh akademiy. Kiyev: KVITs.
Suyevalov L. F. (1977). Spravochnik po raschetam sudovykh avtomaticheskikh sistem. Leningrad : Sudostroyeniye.
Fossen Thor I. (2002). Marine Control Systems, Guidance, Navigation, and Control of Ships, Rigs and Underwater Vehicles. Marine Cybernetics, Trondheim, first edition. Retrieved from http://www.marinecybernetics.com.
Fossen Thor I. (2011). Handbook of Marine Craft Hydrodynamics and Motion Control. Hoboken, N.J. : Wiley ; Chichester : John Wiley [distributor.
Sorensen Asgeir J. (2011). Survey of dynamic positioning control systems. Annual Reviews in Control, 35, 123–136.
Fossen, T. I., Perez T. (2004). Marine Systems Simulator (MSS), 2004. Retrieved from https://github.com/cybergalactic/MSS
Fossen S., Fossen T. I. (2018). eXogenous Kalman filter (XKF) for Visualization and Motion Prediction of Ships using Live Automatic Identification System (AIS) Data. Modeling, Identification and Control, Vol. 39, No. 4, 233–244.
Perez T. (2005). Ship Motion Control : monograph. Berlin, Springer.
Perez, T., Fossen T. I. (2009). A Matlab Tool for Parametric Identification of Radiation-Force Models of Ships and Offshore Structures. Modelling, Identification and Control, MIC-30(1):1-15.
Fossen Thor I., Perez Tristan. (2009). Kalman Filtering for Positioning and Heading Control of Ships and Offshore Rigs. IEEE Control Systems Magazine, December 2009, 33-46.
Budashko, V. V. (2015). Implementarnyy podkhod pri modelirovanii energeticheskikh protsessov dinamicheski pozitsioniruyushchego sudna. Elektrotekhnika i Elektromekhanika, 6, 2025.
Rozhkov S. O. (2015). Modelyuvannya systemy dinamichnoho pozitsiyuvannya sudna-postachalʹnyka typu PSV. Vestnik Khersonskogo natsional’nogo tekhnicheskogo universiteta, 04(55), 159–166.
Vagushchenko L. L., Vagushchenko A. L. & Zaichko S.I. (2005). Bortovyye avtomatizirovannyye sistemy kontrolya morekhodnosty. Odessa : Feniks.
