Basharat Mehmood

Outdoor polymeric insulators are crucial components of the overhead power distribution and transmission network. However, leakage current (LC) develops on polymeric insulators, particularly in areas with severe contamination, which may lead to deep erosion from a severe (eroding) dry-band arcing (DBA). The erosion exposes the fiberglass core to weathering, leading to insulator failure. Silicone rubber (SR) is a commonly used insulating material for outdoor applications and has shown an outstanding erosion performance during the inclined plane test (IPT) under mild test voltages. However, more severe (critical) voltages are required to test strong materials that are highly loaded with inorganic fillers and in use today. Critical test voltages have been shown leading to material puncture or deep erosion with combustion under the eroding DBA. Current methods, such as analyzing LC waveforms using third harmonic and wavelet transform techniques, have demonstrated effectiveness in detecting DBA during IPT and correlating LC with erosion taking place gradually on the surface. However, the deep erosion rather takes place over much shorter periods of time under the eroding DBA, necessitating a reliable supporting technique to detect the phenomenon. Additionally, identifying material failure based on visual observations would also not be feasible during the IPT, as these techniques may not clearly identify deep erosion in the presence of liquid contaminant, continuous DBA activity, and surface residue. There is a critical need for an online and a non-intrusive method of identifying deep erosion failure during the IPT. Therefore, this research proposes the use of ultra-high frequency (UHF) detection technique of deep erosion failure during the IPT. The proposed method has the potential to be implemented as a reliable online and non-intrusive technique to identify deep erosion failure during the Inclined Plane tests.