Investigation on aging of stator bar insulation based on JTFA of PD pulse waveforms

Author

Zhang, Xiaohong ; Yu, Longbin ; Yue, Bo ; Xie, Hengkun

Author_Institution

Inst. of Electr. & Electron. Eng., Harbin Univ. of Sci. & Technol., China

Volume

1

fYear

2003

fDate

1-5 June 2003

Firstpage

270

Abstract

In the present paper, partial discharge (PD) pulse waveforms of stator bar insulations subjected to various aging factors are investigated by means of extra-high frequency PD measurement technique. The test results indicated that both rising time of PD pulse and pulse width vary with aging time. Although different aging factors, such as electrical, electrical-thermal and thermal-mechanical stresses etc., result in different alteration in PD pulse waveform, it is observed that high frequency components in the time-frequency spectrum of PD pulse waveform add with aging time in all of specimens by joint time- frequency analysis (JTFA). If high frequency components in dispersion appear in JTFA spectrum, it is though that oxides with low-molecule weight are produced due to PD in the void and acidic matter deposited on the surface of dielectric around the void erodes the dielectric and results in electrical tree spreading out.

Keywords

ageing; mica; partial discharges; stators; time-frequency analysis; trees (electrical); JTFA; acidic matter; aging; electrical tree; electrical-thermal stress; joint time- frequency analysis; partial discharge pulse waveforms; stator bar insulation; thermal-mechanical stress; time-frequency spectrum; void erodes; Aging; Dielectrics; Frequency; Insulation; Measurement techniques; Partial discharges; Pulse measurements; Space vector pulse width modulation; Stators; Thermal stresses;

fLanguage

English

Publisher

ieee

Conference_Titel

Properties and Applications of Dielectric Materials, 2003. Proceedings of the 7th International Conference on

ISSN

1081-7735

Print_ISBN

0-7803-7725-7

Type

conf

DOI

10.1109/ICPADM.2003.1218404

Filename

1218404