Title :
Failure analysis of dry-type power transformer
Author_Institution :
Earth Tech, Oakland, CA, USA
Abstract :
This paper provides the failure analysis of a three-phase, dry-type, silicone resin vacuum-pressure encapsulated, 750/1000 kVA, AA/FA, 34.5 kV-480 Y/277-V, delta-wye power transformer. Transient overvoltage switching surge propagation through the transformer winding and protection margin is discussed. An arbitrary sensitivity of 10 pC at 120% rated voltage generally used for the partial discharge tests at the factory may be inadequate for the design of the failed transformer
Keywords :
failure analysis; insulation testing; overvoltage; partial discharge measurement; power transformer insulation; power transformer testing; reliability; switching transients; transformer windings; 1000 kVA; 277 V; 34.5 kV; 480 V; 750 kVA; delta-wye power transformer; failure analysis; partial discharge tests; protection margin; silicone resin vacuum-pressure encapsulation; three-phase dry-type power transformer; transformer winding; transient overvoltage switching surge propagation; Arresters; Circuit breakers; Failure analysis; Power system modeling; Power system protection; Power system transients; Power transformers; Surge protection; Switches; Voltage control;
Journal_Title :
Industry Applications, IEEE Transactions on
