부산대학교 도서관

The first article in this issue is "Health indexes for power transformers: A case study" by Felix Ortiz and collaborators from the University of Cantabria, Santander, Spain. Using the results of measurements on oil samples taken from a transformer, e.g., dielectric strength, dissipation factor, color, interfacial tension, and concentrations of dissolved gases, furans, acids, and moisture, it is possible to determine whether a transformer has developed certain specific faults, e.g., partial discharges, arcing, sparking, overheating, etc. On the other hand, various health indexes have been proposed to characterize the general condition of a transformer. The factors taken into account vary between indexes, and are given different statistical weightings depending on their influence on the general condition of the transformer. In this article the authors present the results of a study of the condition of a fleet of 52 operating power transformers, using two recently proposed health indexes.