Partial discharge monitoring for power transformers using UHF sensors Part 2: Field experience

M.D. Judd, Li Yang, I.B.B. Hunter

Research output: Contribution to journalArticle

152 Citations (Scopus)


Because of the large capital value of power transformers and their critical role in the electricity network, there is an increasing need for non-intrusive diagnostic and monitoring tools to assess their internal condition. The UHF technique is being applied increasingly to monitor partial discharges (PD) in power transformers and has been shown to be much more sensitive than acoustic techniques when the signal path passes through solid insulation. Field trials were performed on five power transformers ranging in size from 18 to 1000 MVA and in voltage from 25 to 400 kV. The results of PD tests on power transformers provide sufficient evidence to justify making provision for UHF sensors on new transformers to facilitate their monitoring when required during the service lifetime.
Original languageEnglish
Pages (from-to)5-13
Number of pages8
JournalIEEE Electrical Insulation Magazine
Issue number3
Publication statusPublished - Jun 2005



  • power transformers
  • electricity networks
  • diagnostic tools
  • UHF sensors
  • electrical insulation

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