Institut de Recherche d'Hydro-Quebec, Varennes, Quebec
Pages: 115 Published: Jan 1983
Efficient utilization of electrical insulating materials in electrical apparatus, devices, and cables requires knowledge of the dielectric loss behavior of materials under specific voltage, frequency, and temperature conditions. The appearance of significant dielectric losses may not only represent an unnecessary energy loss but could possibly lead to failure due to thermal instability. Also at higher frequencies, losses will give rise to attenuation and, hence, a loss in transmitted signal information. Because of the large number of available insulating materials, it is not practically feasible in a chapter of acceptable size to present a greatly detailed description of the loss mechanisms in every important insulating material or system. It is much more helpful as well as expedient in an introductory chapter to discuss and compare the loss processes in different generic materials such as polymers, glasses, and ceramics. This will help to delineate the differences in the loss processes as a function of the material type and molecular structure and thus provide the insulation engineer and scientist with a general idea of how molecular structure and associated impurity content influence the dielectric behavior of certain groups of materials. In addition, the treatment of fundamental concepts in dielectric theory will serve as a useful preamble for the reader to the specialized topics to be dealt with in subsequent chapters of this volume.
Paper ID: STP37836S