DocumentCode
2475007
Title
Degradation of ZnO varistor and its dielectric relaxation
Author
Wang, Huifang ; Xu, Yan
Author_Institution
Dept. of Solid State Electron., Huazhong Univ. of Sci. & Technol., Wuhan
fYear
1993
fDate
17-20 Oct 1993
Firstpage
544
Lastpage
549
Abstract
Dielectric relaxation spectra are used to study the degradation of a ZnO varistor under 8/20μs impulse current. The relationship between dielectric relaxation spectra and the distribution of migration ions is investigated. Dielectric-relaxation measurement is shown to be a reliable method for studying the degradation of non-Ohmic ZnO ceramics. The frequency spectra of dielectric loss are shifted to low-frequency regions after stressing by impulse current. The shift is attributed to the formation of equivalent dipoles in the grain boundary by the migration of interstitials
Keywords
dielectric losses; dielectric relaxation; grain boundaries; interstitials; varistors; zinc compounds; 8 to 20 mus; ZnO varistor; ceramics; dielectric loss; dielectric relaxation; frequency spectra; grain boundary; interstitials; migration ions distribution; Capacitance measurement; Ceramics; Current measurement; Dielectric loss measurement; Dielectric losses; Frequency; Thermal degradation; Varistors; Voltage; Zinc oxide;
fLanguage
English
Publisher
ieee
Conference_Titel
Electrical Insulation and Dielectric Phenomena, 1993. Annual Report., Conference on
Conference_Location
Pocono Manor, PA
Print_ISBN
0-7803-0966-9
Type
conf
DOI
10.1109/CEIDP.1993.378916
Filename
378916
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