This is the goal of a consortium that Siemens has founded in cooperation with researchers from the universities of Bayreuth and Dortmund and the companies KREMPEL Group, RWE, and Nanoresins as part of a project funded by the German Ministry of Economics and Technology. The official name of the project is “Ausnutzungssteigerung von Generatoren” (Boosting the efficiency of generators); however, it is normally referred to simply by its abbreviation, AvG.

The aim is to upgrade existing generators by installing additional conductors and replacing the stator’s copper coil with a bigger one. The insulation poses a particularly difficult challenge, however, as it has to be as thin as possible and provide better protection against disruptive discharges in order to offset the bigger coil’s need for more space. Tiny rock particles known as mica are conventionally used for the insulation. Now, CT has developed new insulation materials that contain not only mica but also nanoparicles based on phyllosilicates and spherical SiO2, which have huge surface areas in relation to their volume. Erosion channels that cause disruptive discharges have to take a longer path as a result, thus increasing resistance to partial discharges as much as tenfold. While scientists in Dortmund are investigating the interactions between the insulating material and the nanoparticles, researchers in Bayreuth are examining how the nanoparticles can best be processed. All of these insights are pooled at Siemens, where they are helping in the development of a system that will be close to the final product.