Increasing the operating range of permanent magnet synchronous motors by switching the winding configurations

This paper presents a holistic approach to determine the effect of online reconfiguration of the motor winding of a synchronous permanent magnet motor resulting in switching the number of turns. The analysis is based on a parameter plane, which predicts the behavior of synchronous machine designs by using only two normalized parameters, the permanent magnet flux linkage and the ratio of the quadrature axis inductance L
_q
to the direct axis inductance L
_d
. This enables a fast and reliable evaluation of all alternate winding configurations under given constraints. By generating a Pareto front, superior switching configurations can be identified. An exemplary configurable winding machine - implemented in a finite element analysis (FEA) - shows a significant improvement with respect to maximum torque (increase by 20.3%) and usable torque-speed operating range (increase by 5.5%) compared to the best fixed-winding configuration. The contribution demonstrates that this approach is not only applicable for permanent magnet synchronous motors but also for synchronous reluctance, electrically excited synchronous and induction motors.