For the compression of round enameled wire, scientific methods are used to study the feasibility of forming operation in the groove of the motor after the winding process. The motivation for this method is that it requires a higher fill
factor, which is comparable to the hairpin technique. However, by using separate parallel conductors with a higher number of turns, it is also possible to reduce frequency-related losses in a higher driving speed range. In addition, due
to the coating process, the quality of the insulation layer of the round wire is better than that of the special-shaped wire, except for the extrusion insulation. This makes round wires more suitable for compression and higher voltage
applications. First, the current technical state is introduced, and the applicable winding test procedures and test settings are introduced. For experimental verification, a model groove was designed and built. Introduce and select
possible groove design parameters according to the design of experiment method (DoE). The different measurement methods used to characterize the insulation quality after processing and the resulting wire deformation are discussed. The
important input variables are pressure, wire insulation thickness (measured in grade), number of turns per coil, and wire diameter. The key output variables are the achieved fill factor improvement, partial discharge voltage and coil
resistance. According to the experimental plan of full factor DoE, the selected methods and conclusions are being discussed based on the main effects diagram. In the outlook, further investigation topics are outlined. It can be proved
that the compression process of enameled round copper wire is very suitable, reaching the critical limit of quality, and is used for the production improvement of the coil in the groove of the motor.