Interaction between a spray-insulation for phase separation in the winding head and the following impregnation process in insertion winding stators

As part of the secondary insulation system for insertion winding stators, a new method was developed to apply the interphase insulation in the winding head. This invention is based on a robot guided spraying process that applies a plastic insulation layer on to the respective winding parts in the stator winding head. With an initial material selection and the construction of a prototype machine, the basic suitability as an automatable phase isolation process was verified in a previous paper at FAIM2021. For the use of spray insulation in the complex general system of insulation of an electrical machine, the new insulation must meet similar requirements as the paper insulation frequently used up to now. It is therefore essential to analyze the interactions between the newly applied spray insulation and further downstream processes, such as subsequent impregnation. Therefore, in this paper, the mechanical and electrical properties of unimpregnated and impregnated spray insulation layers are analyzed using DoE studies.