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- Resumen es exacto "Polymeric electrical insulations are widely used in high and medium voltage power systems for the following reasons: they minimize vandalism problems, have good behavior in cases of high environmental pollution, have less weight and easy maneuverability, have less visual environmental impact, and they do not project parts in an explosion. They apply to overhead lines and substation equipment. Unlike the classic porcelain and tempered glass insulation, in this case it is necessary to evaluate its aging state. The test methods provided for in the current international standards do not include characterization tests that allow evaluating the aging of the materials that make up the polymeric insulators, especially their housing. Although the study groups dedicated to issues related to high voltage power electrical systems have developed characterization methodologies for this type of materials, they are not applicable to equipment in service, either because it requires extracting samples (being then, at least partially, destructive methods), or are carried out on large samples that could not be extracted from such equipment. Non-destructive methodologies applicable to the dimensional variety, and characteristics, of the typical equipment of high and medium voltage installations have not yet been developed. In this work, an essentially non-destructive methodology is presented, suitable for evaluating equipment in its place of installation, based mainly on "Dielectric Spectroscopy", and framed in a characterization test plan satisfactorily contrasted with vast experience in technical management of this type of materials. Based on the results of many tests, carried out with various instruments, and under different conditions, the feasibility of the proposed methodology is demonstrated. A novel sample holder device design, developed for this specific purpose, is also presented. And, not least, to support the method from a theoretical point of view, a comprehensive analysis of the theory of "Dielectric Spectroscopy" is presented, and the usual theory based on phenomenological formulations (Cole-Cole, Cole- Davidson and Havriliak-Negami) is related with the latest developments that deduce them from the Fractional Calculus."
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