Title :
Initiation and growth of electrical trees in LDPE generated by impulse voltage
Author_Institution :
Dept. of Electr. Eng., Chiba Inst. of Technol., Narashino, Japan
Abstract :
Using a molded LDPE specimen with a metal foil electrode, the initiation and growth of electrical trees generated by positive and negative impulse voltages were studied. The Weibull plots of the numbers of impulse voltage shots up to the tree initiation and to the puncture of the specimen were analyzed. The difference between the plots of positive and negative impulse shots demonstrates the difference between the initiation and growth of a positive impulse tree and those of a negative one. Taking account of the results of the electric field calculation in the vicinity of the electrode, the tree initiation mechanism was examined. The difference of the tree initiation between a positive impulse tree and a negative one is suggested to be due to the difference between the tree growth following the initiation processes
Keywords :
Weibull distribution; electric strength; impulse testing; insulation testing; polyethylene insulation; trees (electrical); LDPE; Weibull plots; electric field calculation; electrical tree growth; electrical tree initiation; metal foil electrode; molded LDPE specimen; negative impulse voltages; positive impulse voltages; specimen puncture; tree inception voltage; Breakdown voltage; Dielectrics and electrical insulation; Electrodes; Grounding; Impulse testing; Optical microscopy; Pulse generation; Shape; Surges; Trees - insulation;
Conference_Titel :
Electrical Insulation and Dielectric Phenomena, 1996., IEEE 1996 Annual Report of the Conference on
Conference_Location :
Millbrae, CA
Print_ISBN :
0-7803-3580-5
DOI :
10.1109/CEIDP.1996.564623
