Polymeric Insulation Systems in High Voltage Engineering

Abstract

The aim of the study is to consider the possibilities of developing high-voltage technologies with the use of polymeric insulation taking into account further prospects of its application. The use of various types of polymers starting from the 19th century is reviewed. The types of equipment involving the use of high-voltage polymeric insulation and the history of their development are described in detail. The presented results demonstrate the widespread use of this type of insulation and allow the ways of its future use to be estimated. Relatively low mechanical strength and heat resistance, and organic insulation susceptibility to atmospheric-induced degradation and ageing were among the main drawbacks hindering widespread use of polymeric materials in electric power engineering up to the mid 20th century. However, these shortcomings were overcome owing to the transition to composite materials. With the development of various insulation manufacturing technologies involving the use of additions, epoxy compounds were obtained. This opened the possibility not only to increase the number of equipment types with polymeric insulation, but also to extend the nominal voltage ranges of devices, increase their service life, and decrease their cost. Apart from reviewing the existing solutions for manufacturing and applying polymeric insulation, possible ways to improve them are studied. Thus, owing to improvement of manufacturing technologies and optimization of the compound composition, the occurrence of dangerous gas inclusions, cracks, and exfoliations larger than a few micrometers in size are minimized in polymeric insulation systems (partial discharges appear in such dislocations under the effect of voltage). When exposed to atmospheric air, moisture, acids and other chemically active components able to destruct the insulation may penetrate into gas interlayers. Higher dielectric strength of insulation can be achieved by taking into account the quality of adhesion between the main compound and various elements (electrodes and other poured dielectrics).