Reading Recommendation: Application of low frequency dielectric spectroscopy to estimate condition of mineral oil

Paper about dielectric spectroscopy application in HV equipment & materials.

Abstract
Conventional loss factor and capacitance measurements are used to determine condition of insulating liquid. In the new IEC 61620 standard capacitance and conductance are measured at low voltage and low frequency with square wave method to over come some difficulties of the conventional method. Nowadays low frequency dielectric spectroscopy becomes a powerful diagnostics tools for high voltage apparatus and utilities provide spectroscopy measurement system for diagnosis of their power apparatus. In this paper is shown that the space charge polarization can be observed with low frequency spectroscopy for insulating liquids. Increase of capacitance at low frequency can be defined as a new parameter and help to accurate determination of state of insulating liquid. Space charge polarization of insulating liquids can influence the result of dielectric spectroscopy of liquid impregnated insulation system too and must be considered for better interpretation of spectroscopy results.

Shayegani, A.A. Borsi, H. Gockenbach , E. Mohseni, H. Div. of High Voltage Eng., Hannover Univ., Germany;
This paper appears in: Dielectric Liquids, 2005. ICDL 2005. 2005 IEEE International Conference on
Publication Date: 26 June-1 July 2005
On page(s): 285- 288
ISSN: ISBN: 0-7803-8954-9
INSPEC Accession Number: 8565526
Digital Object Identifier: 10.1109/ICDL.2005.1490082
Current Version Published: 2005-08-01