Online partial discharge Measurements in power transformer

Abstract

Transformers as crucial part of the electric network ensure reliable newlineAnd safe energy exchange over wide areas between consumers and suppliers newlineAnd they also represent a large capital value With the growing demand of newlinePower power quality and power availability the stringent need for system newlineReliability is inevitable Hence a general growing focus on cost effective newlineCondition based maintenance cbm strategies instead of time based newlineApproaches can be seen Cbm tactics may require a whole set of monitoring newlineAnd diagnostic techniques Beside several established methods to gather newlineInformation about the current condition of a transformer on a temporal basis newlineThere is an increased need for possibilities of conducting the diagnostics in an newlineOn line manner In view of the general advantages of on line measurements newlineAs there are a realistic stresses for the measurements and b permanent newlineMonitoring and inspection capabilities this is quite comprehensible newlineThe diagnostic examination of partial discharges pd is regarded newlineAs a powerful nondestructive and sensitive diagnostic tool for the condition newlineAssessment of insulating systems at factory Electric pd measurements newlineConducted according to the iec 60270 standard are often referred to as newline Conventional method If performed on site and on line measurements on newlineTransformers show certain limitations regarding the applicability of sensors newlineAnd the receptivity for several disturbances In contrast the non conventional newlineElectromagnetic ultra high frequency antenna uhf high frequency newlineCurrent transformer hfct and acoustic emission ae pd measuring newlineMethods have advantages for on site on line applications newline newline