Space charge behavior in oil-paper insulation under polarity reversed voltage

Author

Da Wang ; Shiqiang Wang ; Min Lei ; Haibao Mu ; Guan-Jun Zhang

Author_Institution

State Key Lab. of Electr. Insulation & Power Equip., Xi´an Jiaotong Univ., Xi´an, China

fYear

2012

fDate

23-27 Sept. 2012

Firstpage

265

Lastpage

268

Abstract

Converter transformers are suffered from DC voltage, DC voltage with AC voltage and polarity reversed voltage additionally, compared with common power transformers. Under DC voltage it is easy to form space charge in oil-paper insulation. The formation, distribution and mobility of space charge will affect its dielectric performance. What´s more the insulation system is easier to fail under polarity reversed voltage. In order to observe space charge behavior in oil-paper insulation under different polarity reversed conditions, space charge measurement is made under different voltage reversed polarity (from positive to negative and from negative to positive) and different voltage reversed time (20s, 30s, 40s and 60s) separately. The pulsed electro-acoustic (PEA) method is used for space charge measurement at room temperature. The impact of voltage reversed polarity and voltage reversed time on space charge characteristics was discussed. Besides the electric field distortion in samples with different polarity reversed conditions is calculated. The experimental results show that polarity reversed conditions have great effect on space charge characteristics.

Keywords

paper; power transformer insulation; pulsed electroacoustic methods; space charge; transformer oil; AC voltage; DC voltage; PEA method; converter transformers; dielectric performance; electric field distortion; insulation system; oil-paper insulation; polarity reversed voltage; power transformers; pulsed electroacoustic method; space charge behavior; space charge characteristics; space charge measurement; temperature 293 K to 298 K; time 20 s; time 30 s; time 40 s; time 60 s; voltage reversed time; Charge measurement; Electric fields; Insulation; Power transformer insulation; Space charge; Temperature measurement; Voltage measurement; oil-paper insulation; polarity reversed voltage; pulsed electro-acoustic (PEA); space charge;

fLanguage

English

Publisher

ieee

Conference_Titel

Condition Monitoring and Diagnosis (CMD), 2012 International Conference on

Conference_Location

Bali

Print_ISBN

978-1-4673-1019-2

Type

conf

DOI

10.1109/CMD.2012.6416427

Filename

6416427