Safety and reliability of electrical insulation

Abstract

The insulators, in their daily operation, are subject to the action of the environment and their own exploitation, being understood between the latter the tensions at the frequency of the system and the surges that originate from different causes. In the case of the environment are two fundamental factors that cause the insulator to lose its insulating characteristics: The accumulation of polluting particles on the surface of the same that when it is wetted by light rain or fog becomes conductive, to such an extent that an arc of current, or discharge, is established between the structure that supports the insulators and the conductors, damaging the whole assembly and causing cuts or interruptions in the transmission or distribution of energy, causing reliability problems of the service, on the other hand, The metal parts of the insulators are affected by corrosion problems affecting their mechanical characteristics. Industrial users demand high reliability services, which not only comply with certain voltage and frequency ranges but also offer continuity in service; Among the processes that are most affected by the cuts in the service are those of automatic industrialization, because they are increasingly sensitive and can alter a process with a minimum interruption in service and causing millions in losses. Determine when to take corrective actions to anticipate transient or permanent failures in high voltage insulators has been a problem for companies in the electricity sector for many years; In the case of pollution, the solution has been towards the replacement of the insulation or the execution of periodic washings of the same, sometimes without any technical criteria, which demands a considerable workforce. In the case of corrosion or the partial or total destruction of insulation by surges, companies have no choice but to replace the insulation when the failure occurs, in general, or what is known as the application of corrective maintenance. In recent years, this problem has become more important as a result of the free competition of companies in the electricity sector, since it requires an optimization of them and therefore a reduction in maintenance and labor costs. The present work tries to expose the close relationship that exists between isolation and reliability from the new paradigms that appear in the maintenance activity, which offer some interesting changes in the environment until now seen in this direction.