Quality Tests on Field Aged Composite Insulators of Hellenic Electricity Distribution Network

In this paper, an investigation on the quality of HTV silicone rubber medium voltage composite insulators was performed. More specifically, visual inspection, hydrophobicity classification (by an operator and by a convolutional neural network) and shore A hardness measurements were performed on new and used (after their removal from the electricity grid of Evia Island in Greece) suspension and line-post composite insulators. The tested insulators came from two manufacturers and they were operational in the electricity grid from 0 to 10 years. The results showed that these three tests are able to give a first good assessment of the condition of composite insulators. Furthermore, there seems to be a correlation between the shore A hardness measurement and operational years of composite insulators.