Partial discharges emission testing in the generator winding insulation in the time-frequency domain
Authors:
- Mieczysław Zając,
- Maciej Sułowicz,
- Janusz Petryna
Abstract
The insulation of stator windings subjected to natural aging processes, is exposed to various unfavorable phenomena, mainly electrical, mechanical, thermal, thermomechanical, as well as the emission of partial discharges. Monitoring the changes in the nature of these discharges over long periods of time allows to follow the aging process of insulation systems and plan renovation or modernization works responsibly. The article presents the use of narrow band wavelet detection filters for analyzing the intensity of partial discharges in the generator's winding insulation. The diagnostic signal characterizing the course of their emission is a voltage signal proportional to the current derivative registered in the measuring system including Rogowski coils. After initial testing, the formation of the orthonormal wavelet base of the detection filters was based on the application of selected higher degrees Legendre orthogonal polynomials. The article shows an example of the usage of basic wavelet synthesis based on the 16th-degree polynomial. It was found out that the chosen polynomial maps properly the characteristic properties of a voltage signal proportional to the current derivative. Based on wavelet bases structured in this way, numerical analyzes were performed, and the results of them are presented in the form of energy distributions of details. It has been shown that the analysis of partial discharges emissions during the operation of machines provides valuable information about the quality of their execution technology, as well as on the current state of the windings insulation systems. The choice of the analysis method was dictated by the non-stationary nature of the physical processes associated with partial discharges.
- Record ID
- CUT7ffe7de567664d86b57d28636a587d54
- Publication categories
- ; ;
- Author
- Pages
- [1-8]
- Other elements of collation
- tab.; wykr.; Bibliografia (na s.) - [8]; Bibliografia (liczba pozycji) - 7; Oznaczenie streszczenia - Abstr.
- Book
- 2018 International Symposium on Electrical Machines (SME) : SME 2018, Andrychów, Poland, 10-13 June 2018, 2018, [S.l.], Institute of Electrical and Electronics Engineers, IEEE, [8] p., ISBN 978-1-5386-5210-7
- Keywords in English
- diagnostics, generators, faults, signal processing, time-frequency analysis, wavelets, orthogonal polynomials
- DOI
- DOI:10.1109/ISEM.2018.8442976 Opening in a new tab
- URL
- https://ieeexplore.ieee.org/document/8442976/ Opening in a new tab
- Related project
- Language
- eng (en) English
- Score (nominal)
- 20
- Publication indicators
- = 0
- Additional fields
- Indeksowana w: Scopus
- Uniform Resource Identifier
- https://cris.pk.edu.pl/info/article/CUT7ffe7de567664d86b57d28636a587d54/
- URN
urn:pkr-prod:CUT7ffe7de567664d86b57d28636a587d54
* presented citation count is obtained through Internet information analysis, and it is close to the number calculated by the Publish or PerishOpening in a new tab system.