High-Frequency Models for the Prediction of Transient Effects in Motor Windings under Fast Rising Impulse Voltages

Due to the new generation of power electronics, a set of steep-fronted PWM voltage waves penetrates into motor windings and results in a highly uneven distributed voltage among the turns in the first coil of each stator phase. Thus, a method of accurately predicting these transient effects of the first few turns is necessary and vital for the possible improvement of machine designs in the future. In this paper, two High-Frequency (HF) models based on multiconductor transmission lines (MTLs) and nodal equations using the Finite Element Method (FEM) as well as MATLAB are developed. In addition, comparisons between measured and simulated results through impedance and potential measurements are demonstrated to validate these theoretical methods along with assumptions and simplifications made for the models. This publication is funded by the German Federal Ministry of Education and Research (BMBF).