New epoxy composite insulating material with nano fillers and micro fillers of silica with higher thermal conductivity

摘要

This article describes the influence of thermal properties of materials to properties of electrical insulating systems (EIS) in electrical rotating machines. Multi-component composite materials combine the advantage of the individual materials, and allow generate new materials with better properties than those of individual components (the synergistic effect). The objective of this experiment is to improve the thermal and electrical properties of epoxy composites using nano fillers and micro fillers of silica 1% (SiO2 supplementing fillers of silica with better thermal conductivity (1,5 (W·m-1·K-1)) to the electrical insulating systems with typical values of thermal conductivity λ = 0,2 (W·m-1·K-1) can be modified (to increase) of its thermal conductivity [1], [7]. The electrical insulating systems consists of glass cloth (λ = 0,6 - 1,2 (W·m-1·K-1)), an epoxy resin (binder) (λ = 0,2 (W·m-1·K-1)) and a standard mica paper (λ = 0,3 - 0,6 (W·m-1·K-1)) [1], [18]. Fillers with low thermal conductivity form a barrier to the flow path of heat from the beginning (from winding) in the electrical device to the cooling medium. Furthermore, this article describes the electrical properties of nanocomposites based on epoxy resin filled of nano particles of hydrophobic and hydrophilic silica (1%).