Modeling and analysis of AC resistance of a permanent magnet machine for online estimation purposes

A simple and accurate AC resistance model is essential for online estimation of copper loss which can be utilized in several ways of controlling and monitoring. This paper presents application of Squared Field Derivative on three-phase IPM machine to model AC resistance of rectangular conductors. It focuses on Finite Element Analysis to validate analytical model. The deviations from analytical model due to saturation and field weakening at high speeds are studied in detail and the significance of these deviations on the context of operating regions is discussed. This paper also presents application of the same analytical approach to model AC resistance of overhang conductors.