Recent trends of low-viscosity silicone liquid immersed transformers

In this paper we report on ldquoverification of arcing in insulation fluidrdquo and ldquofire resistance evaluation of insulation fluidrdquo for accident spread prevention measures, as recent trends in low-viscosity (kinematic viscosity 20 mm/s², (20cSt) at 25degC) silicone liquid immersed transformers. The ldquoverification of arcing in insulation fluidrdquo, which simulated transformer internal short-circuit accidents, indicated that protection coordination similar to that for oil-immersed transformers can probably be applied in silicone liquid immersed transformers as well, and also clarified the produced gas patterns. The ldquofire resistance evaluation of insulation fluidrdquo, which simulated transformer disaster accidents, quantitatively evaluated the fire resistance and self-extinguishing performance of 20cSt silicone liquid.