Condition monitoring and fault diagnosis of an MR load tap changer using oil analyses data

Hoda Molavi


Considering the objectives of "condition based preventative maintenance strategy", condition monitoring of an MR M-type load tap changer (LTC) was assessed applying several oil analyses. The analyses consisted of dissolved gas analysis (DGA), breakdown voltage measurement as well as analyses of dissolved metals and suspended particles in oil, were followed by interpretation of the derived data for condition monitoring and fault diagnosis of the pilot LTC.

Finally, the pilot LTC was overhauled after the last oil sampling and the observations from eye inspection were compared to the extracted results from oil analyses data interpretation.


LTC; DGA; Oil analysis; Condition monitoring; Fault diagnosis

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