Известия Томского политехнического университета: Инжиниринг георесурсов (Jun 2021)

DETERMINATION OF RUNNING ELECTRICAL CHARACTERISTICS OF OIL SUBMERSIBLE CABLE

  • Alexander S. Glazyrin,
  • Yusup N. Isaev,
  • Sergey N. Kladiev,
  • Andrey P. Leonov,
  • Ivan V. Rakov,
  • Stanislav V. Kolesnikov,
  • Sergey V. Langraf,
  • Alexander A. Filipas,
  • Vladimir A. Kopyrin,
  • Rustam N. Khamitov,
  • Vladimir Z. Kovalev,
  • Alexey V. Lavrinovich

DOI
https://doi.org/10.18799/24131830/2021/6/3249
Journal volume & issue
Vol. 332, no. 6
pp. 186 – 197

Abstract

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The relevance. Determination of the main electrical parameters of oil submersible cables is associated with the need to create accurate mathematical models of the systems control station – oil submersible cable – submersible motor, in which it is necessary to take into account wave processes in a long cable line arising in connection with the shape pulses generated by frequency converters included in the set of modern control stations. Electrical parameters such as linear capacities and inductances are not standardized in the technical literature and are not indicated in the technical specifications by cable manufacturers. However, it is obvious that the creation of control systems and identification of the SEM operation modes requires the solution of systems of differential equations, which include the specified characteristics as parameters. In addition, modern concepts of frequency control of electric motors, in particular submersible, indicate that during operation of frequency converters based on IGBT transistors, high-frequency overvoltages arise in the SEM supply signal, leading to the appearance of partial discharges in the stator windings of the motors. This fact will be aggravated by the development of deeper fields, with a longer cable length and, accordingly, a greater influence of wave processes on the shape of the signal supplied to the SEM. The main aim of the research consists in development of a method for determining the linear electrical parameters of the submersible cable of any designs and materials used. Methods: methods for solving differential equations, field problems, numerical finite element modeling, and a physical experiment. Results. A method was developed for determining the linear capacities and inductances of conductors and armor of an oil-submersible cable, based on solving differential equations for a «reference» model, numerical modeling of an identical design in COMSOL Multiphysics® Version 5.5a, comparison of the obtained values ​​with experimental data. It is indicated that the finite element modeling in COMSOL Multiphysics® Version 5.5a is correct and with sufficient accuracy (error less than 5 %) coincides with the results of solving the equations given in the reference literature. The linear values ​​of capacities and inductances have been determined for the most common designs of oil-submersible cables.

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