Electrical insulation

 

In the field of electrical engineering the efficiency of a component is decisively determined by the properties of its electrical insulation. Polymer materials are widely known for their good electrical insulation properties. While thermoplastic polymers such as PVC, PP or cross-linked PE dominate the field of cable insulation. The insulation of high voltage generators and transformers are based on thermosets like epoxy resins. At the department of polymer engineering intensive research has been carried out developing new innovative insulation systems for high voltage generators.

State of the art systems are based on mica paper wrapped generator bars impregnated with epoxy resin via VPI-technique (vacuum pressure impregnation). The insulation quality is determined by partial discharge measurements. Scientific research showed an increase in partial discharge resistance through incorporation of nanoparticles.

The research at our department focuses on the substitution of mica by layer silicates and spherical nanoparticles. Homogeneously dispersed silicate platelets have excellent barrier properties due to their high aspect ratio. The homogeneous dispersion, as well as the influence of nanoparticles on viscosity and manufacturing conditions are the main challenges in developing new insulation systems based on nanoparticles. An improvement of the electrical insulation system would permit thinner insulation layers or higher electrical currents respectively. These improvements would increase the efficiency factor followed by an extensive CO2-saving. Hence improved insulation properties can also contribute to clima protection


Contact: M.Sc. Gökhan Bakis
Phone: +49(0)921 55 74 82
Fax: +49(0)921 55 74 73
Email: goekhan.bakis@uni-bayreuth.de

left: barrier properties of exfoliated layered silicates a schematic sketch right: TEM-picture of a layered silicate-epoxy-nanocomposite