Investigation on room temperature vulcanized silicon insulation with and without ath filler loading by incline plane tracking & erosion test method

Summary

Contamination flashovers are still a global problem in the power system. In some polluted locations, up to 33% of all outage faults are attributed to pollution. So continuity of power supply is a major concern in the power system. Robustness in the insulator materials across varying service conditions needed. Insulator manufacturing has switched over from porcelain and glass insulators to silicon rubber due to its light weight and high mechanical strength and better contaminant resisting performance. However, silicone rubber has susceptibility to tracking and erosion due to dry band arcing, also its ageing and long-term behaviour are unknown. These are the reasons, for which, replacement of existing structure of porcelain insulator in the power system by silicone rubber is difficult. So, Room Temperature Vulcanized (RTV) Silicone coating is used in solid insulating material addressing remedies for these issues. Also, resistive properties of RTV coating against contaminant flash over depend upon chemical composition and filler material. Thus, the present study investigates the insulator performance during tracking, erosion and leakage current studies on RTV Silicone with and without filler loading specimens as per IEC 60587 standards for constant tracking voltage. For the leakage current measurement, Pico scope interface and a protective circuit were made across the shunt. The leakage current pattern has been studied with applied voltage for the RTV with & without ATH filler loading silicone rubber material. Chemical analysis on RTV samples like FTIR, thermal study TGA and morphological studies by SEM-EDX have been carried out before & after tracking and erosion test. Results & conclusion shows that RTV samples with ATH filler loading are more electrically resistive during tracking and erosion and exhibits excellent properties compared to RTV samples without ATH filler loading.

Additional informations

Authors

GENTILI, HAVUNEN, RAMAMOORTY

Keywords

Tracking and Erosion, RTV, ATH, TGA, FTIR, SEM, EDXA, IEC 60587