Title :
Dielectric response analysis of real insulation systems
Author_Institution :
ABB Corp. Res., Vasteras, Sweden
Abstract :
Real insulation systems are often heterogeneous and sometimes non-linear. In this paper we discuss the application of dielectric frequency response methods to a number of such practically important systems. Important examples of composite insulation systems are the oil/cellulose insulation of power transformers and the glass-mica-epoxy system of machine insulation. A few examples of non-linear effects and their implication for dielectric response analysis are discussed. These include narrow liquid ducts in transformer insulation, exhibiting a voltage dependent conductivity, polymer cables with water trees exhibiting non-linear behaviour that is the basis for diagnosis. The relation between partial discharges and dielectric response is elucidated and finally the special problems of measuring non-linear field grading material is discussed.
Keywords :
cables (electric); composite insulating materials; electrical conductivity; machine insulation; partial discharges; permittivity; power transformer insulation; trees (electrical); composite insulation systems; dielectric frequency response methods; dielectric response analysis; glass-mica-epoxy system; machine insulation; narrow liquid ducts; nonlinear effects; nonlinear field grading material measurement; oil/cellulose insulation; partial discharges; polymer cables; power transformers; transformer insulation; voltage dependent conductivity; water trees; Cable insulation; Dielectric liquids; Dielectrics and electrical insulation; Ducts; Frequency response; Oil insulation; Petroleum; Plastic insulation; Power transformer insulation; Power transformers;
Conference_Titel :
Solid Dielectrics, 2004. ICSD 2004. Proceedings of the 2004 IEEE International Conference on
Print_ISBN :
0-7803-8348-6
DOI :
10.1109/ICSD.2004.1350276
