ASTM_D_3382_-_13.pdf

Designation:D338213Standard Test Methods forMeasurement of Energy and Integrated Charge Transfer Dueto Partial Discharges(Corona)Using Bridge Techniques1This standard is issued under the fixed designation D3382;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 These test methods cover two bridge techniques formeasuring the energy and integrated charge of pulse andpseudoglow partial discharges:1.2 Test Method A makes use of capacitance and losscharacteristics such as measured by the transformer ratio-armbridge or the high-voltage Schering bridge(Test MethodsD150).Test Method A can be used to obtain the integratedcharge transfer and energy loss due to partial discharges in adielectric from the measured increase in capacitance and tan with voltage.(See also IEEE 286 and IEEE 1434)1.3 Test Method B makes use of a somewhat differentbridge circuit,identified as a charge-voltage-trace(parallelo-gram)technique,which indicates directly on an oscilloscopethe integrated charge transfer and the magnitude of the energyloss due to partial discharges.1.4 Both test methods are intended to supplement themeasurement and detection of pulse-type partial discharges ascovered by Test Method D1868,by measuring the sum of bothpulse and pseudoglow discharges per cycle in terms of theircharge and energy.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.Specific precautionstatements are given in Section 7.2.Referenced Documents2.1 ASTM Standards:2D150 Test Methods for AC Loss Characteristics and Permit-tivity(Dielectric Constant)of Solid Electrical InsulationD1711 Terminology Relating to Electrical InsulationD1868 Test Method for Detection and Measurement ofPartial Discharge(Corona)Pulses in Evaluation of Insu-lation Systems2.2 IEEE Documents3IEEE 286Recommended Practice for Measurement ofPower Factor and Power Factor Tip-up for RotatingMachine Stator Coil InsulationIEEE 1434 Guide to the Measurement of Partial Dischargesin Rotating MachineryIEEE C57.113 Guide for PD Measurements in Liquid-FilledPower TransformersIEEE Standard C57.124 Recommended Practice for theDetection of PD and the Measurement ofApparent Chargein Dry-Type Transformers2.3 AEIC Documents4AEIC T-24-380 Guide for Partial Discharge ProcedureAEIC CS5-87 Specifications for Thermoplastic and Cross-linked Polyethylene Insulated Shielded Power CablesRated 5 through 35 kV,9th Edition,19873.Terminology3.1 Definitions:3.1.1 pseudoglow discharge,na type of partial discharge,which takes place within an expanded discharge channel and ischaracterized by pulses of relatively low magnitude and longrise time.3.1.1.1 DiscussionPseudoglow discharges occur within adiffused discharge channel,whose emitted glow fills the entireintervening gap or cavity space(1).The discharge rate behav-ior as a function of applied voltage is similar to that of the rapidrise time pulse(spark-type)discharges.The successive pseudo-glow discharge pulses occur over the first quadrant of each halfcycle and in some gases,notably helium,their magnitude isfound to diminish to zero.At this point,a transition to apulseless glow discharge can occur.Its occurrence,which ismanifest by distortion in the sinusoidal voltage wave,is rare.1These test methods are under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and are the direct responsibility ofSubcommittee D09.12 on Electrical Tests.Current edition approved Nov.1,2013.Published December 2013.Originallyapproved in 1975.Last previous edition approved in 2007 as D3382 07.DOI:10.1520/D3382-13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from Institute of Electrical and Electronics Engineers,Inc.(IEEE),445 Hoes Ln.,P.O.Box 1331,Piscataway,NJ 08854-1331,http:/www.ieee.org.4Available from The Association of Edison Illuminating Companies(AEIC),600 N.18th St,Birmingham,AL 35291,www.aeic.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 At discharge inception of a single cavity,the pattern ofpseudoglow discharges consists of a single long rise timedischarge current pulse in each half-cycle.It has becomecommon practice to refer to this particular type of pattern asthat of a glow discharge.Pseudoglow partial discharges,which occur at low