Evaluation of Dynamic Hydrophobicity Properties with the Dynamic Drop Test under AC and DC stress and the Hydrophobicity Transfer Test

This paper deals with the development of two test procedures for evaluating the dynamic properties of hy-drophobicity of polymeric insulating materials for high voltage outdoor application. These properties include the retention, the recovery and the transfer of hydrophobicity onto accumulated pollution layers. The Dy-namic Drop Test (DDT) for evaluating the retention and recovery as well as the Hydrophobicity Transfer Test (HTT) have proven to be suitable test methods and the ongoing investigations are intended to im-prove their repeatability and reproducibility. The paper presents test results of the DDT and HTT performed in two independent laboratories with a variety of relevant polymeric insulating materials. The scatter of DDT-results is reduced compared to previous investigations.…