Davide Pinzan presented his IEEE Transactions on Power Delivery paper, Performance of Composite Outdoor Insulator under Superimposed Direct and Switching Impulse Voltages, to Cardiff University’s High Voltage group as a webinar due to the Covid-19 situation. The presentation concluded with an interesting discussion with experts.
In an HVDC bipolar line, when a pole to ground fault occurs, the unfaulted pole’s voltage can experience a disturbance, similar to a standard switching impulse superimposed on the operational direct voltage. This disturbance may cause the overhead line’s outdoor insulator to fail.
The paper addresses this challenge by providing experimental results and, more importantly, a test methodology to assess the insulator performance under any condition. In particular, it analyses the dry condition and multiple conductive rain conditions, typical of industrialised areas such as Europe, North America, Eastern China, and Japan. The physical phenomenon is investigated in three complementary ways:
- A transient simulation, with the Electromagnetic Transient Program EMTP/ATP
- A Finite Element Method (FEM) simulation, with COMSOL MULTIPHYSICS®
- An experimental test programme performed at the High Voltage laboratory of the University of Porto, during his secondment.
References: Davide Pinzan, Fabio Branco, Manu Haddad, Mohammed El Amine Slama, Maurizio Albano, Ronald. T. Waters, Helder Leite, “Performance of Composite Outdoor Insulator under Superimposed Direct and Switching Impulse Voltages,” IEEE Transactions on Power Delivery, 2020, doi: 10.1109/TPWRD.2020.3003980.
Watch the presentation: