Development and Performance Evaluation of Micromagnesium Oxide Filled Silicone Rubber for High Voltage Insulation

Polymeric insulators are being extensively used for outdoor insulation due to their excellent hydrophobic property. Several studies have been reported to evaluate the performance of these insulators as outdoor insulation with micro and nanofillers. These studies indicate, aged insulators under different environmental conditions exhibit considerably poor performance due to reduced tracking and erosion resistance. The present paper discusses the development of micro-filled magnesium oxide silicone rubber (MgOSiR) specimen and its performance for high voltage insulation under various environmental conditions. In the present study, 24 h water absorbance test, inclined plane test (IPT), flashover experiments have been conducted on the developed 30 weight percent (30 wt%) micromagnesium oxide-filled Silicone Rubber specimens (30 MMg) and commercially available Silicone Rubber specimens. The characterization using Fourier Transform infrared spectroscopy (FTIR) indicates micro-filled sample has better resistance to degradation and good hydrophobic recovery. The experimental results reveal that, developed specimens show superior hydrophobic property, tracking and erosion resistance and higher flashover voltage under dry and wet conditions compared to commercial silicone rubber specimen.