Effects of thermo-electrical aging on the properties of epoxy-based nanocomposites for motor insulation

Polymeric nanocomposites are increasingly adopted for replacing traditional impregnation materials in multilayered insulation systems especially in new generation high power inverter-fed Adjustable Speed Drives. In this paper, the results concerning an experimental study aimed at evaluating the performances of several candidate nanocomposites obtained by adding two different nanoclays and an oxide to an epoxy matrix already used for manufacturing insulation system for high power induction motors are presented. The nanofillers have been selected on the basis of their thermal performances due to high operating temperature of the insulation system. The electrical behavior and the partial discharge resistance of the nanocomposites are compared with those of the pure epoxy matrix after an accelerated aging treatment of 1000h in order to select the better candidate as new impregnation materials in multilayered insulation systems.