Pole Transition Under Open Phase Fault Conditions in a Variable Pole Machine

Abstract

A special subcategory of multiphase electrical machines are the so called variable phase-pole machines. They have the ability to electronically change the number of polepairs without any hardware reconfiguration. Moreover, they are inherently fault tolerant due to the higher number of independent windings. These two virtues offer new possibilities for a drivetrain with higher power density and a new level of reliability. This paper presents an adapted post-fault controller performing a pole transition with an open-phase fault. The drive changes the number of pole-pairs without loosing the torque during the transition and minimizes the stator copper losses simultaneously. The validity of the presented control is shown in simulations.