Prediction of PDIV in motor coils using finite element method

The aim of this paper is the presentation of a method allowing the prediction, at the design phase, of the Partial Discharges Inception Voltage (PDIV) in motor coils made with classical enameled wire. The method is based on the comparison of electrical potential values - obtain with a Finite Element simulation - with those given by the Paschen's laws for the same inter-electrode gap. The originality of the study is the consideration of the real length of the electric field lines to compute the gap between the electrodes. With this prediction, it is possible to improve the capabilities of the Electrical Insulation System (EIS) of motors built in large series.