Effects of Corona Ring Design upon Impulse Voltage Withstand Level of 380 kV V-Strings

İlhan S., Özdemir A.

IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION, vol.18, no.5, pp.1638-1646, 2011 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 18 Issue: 5
  • Publication Date: 2011
  • Doi Number: 10.1109/tdei.2011.6032834
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1638-1646
  • Keywords: Corona ring, flashover voltage, lightning impulse, switching impulse, withstand voltage, ELECTRIC-FIELD, AIR GAPS, INSULATOR, TOWER, TESTS
  • Istanbul Technical University Affiliated: Yes


This study presents the influence of corona rings on impulse withstand performance of 380 kV V-insulator strings. Those strings comprising cap-and-pin type glass insulator units are one of the most common configurations in Turkish National Power Transmission System. Laboratory test setup was constructed for the centre phase of a full scaled tower. Laboratory tests are performed to investigate the lightning and switching impulse performance of the strings equipped with the existing racket type corona rings and the circular type corona rings. Withstand voltages, lower flashover probability levels, flashover routes and times to flashovers are determined under dry and wet test conditions. In addition, some 3D field simulations regarding potential and electric field distributions are also performed for the interpretation of insulator surface flashovers.