Transient electric circuit network method for eddy current losses in flat-wire windings of electric vehicle motors

The rapid adoption of electric vehicles has driven significant advancements in electric drive systems. Flat-wire windings are commonly employed in electric vehicle motors due to their high slot fill factor and superior heat dissipation characteristics. As electric vehicle systems progress towards higher frequencies and voltages, the increased power density and electromagnetic load lead to intensified motor saturation, resulting in higher winding AC losses. Accurate calculation of these losses is essential for optimizing electric vehicle motor design. This paper proposes a transient electric circuit network method based on electromagnetic induction, and presents calculation approaches for two key parameters: network resistance and network induced electromotive force. The method is applied to analyse the AC losses in electric vehicle motor windings, with consideration given to the effects of temperature and speed. The results are compared with those obtained from finite element method for transient eddy current losses, validating the accuracy and efficiency of the proposed method. This method offers a rapid and reliable tool for evaluating AC losses in electric vehicle motor windings.