A study on the use of zinc oxide micro-varistor based field grading materials for composite line insulators

Keskin Arabul F., Arabul A. Y., Cherney E., Jayaram S.

2023 IEEE Electrical Insulation Conference (EIC), Quebec, Canada, 18 - 21 June 2023, pp.117-120

  • Publication Type: Conference Paper / Full Text
  • Doi Number: 10.1109/eic55835.2023.10177327
  • City: Quebec
  • Country: Canada
  • Page Numbers: pp.117-120
  • Yıldız Technical University Affiliated: Yes


This paper examines the reduction in the electric field at the line end of a 230 kV composite suspension insulator that can be obtained by applying a field grading material (FGM) to the insulator core at the line end of the insulator. The FGM is based on a highly non-linear conductivity zinc oxide micro-varistor material; and COMSOL® Multiphysics version 5.6 at power frequency AC is used in the analysis. FGM of various nonlinearities and various lengths applied to the core is studied to determine the non-linear characteristics of the FGM and the length of application that provides the greatest reduction in the electric field. The results are compared to the same insulator fitted with a proper design of corona ring and the simulation results show that the corona ring can be eliminated by using the FGM.