Fault-Tolerant Operation of Brushless Machines Having Magnets in the Stator

The doubly salient permanent magnet (DSPM) machine is a new class of brushless machine having magnets in the stator. In this paper, a strategy for fault-tolerant operation of a DSPM motor drive is proposed. In order to enhance the faulty electromagnetic performance, the DSPM motor operates in a remedial brushless AC (BLAC) mode under the open-circuit fault condition, although it operates in conventional brushless DC (BLDC) mode under normal condition due to its trapezoidal back-EMIT. Based on coupled magnetic and electric circuit solvers, a new co-simulation model is developed to predict the behaviors of the DSPM motor drive under normal and fault conditions. Both co-simulation and experimental results show that the presented fault-tolerant stator-PM motor drive is a vital candidate in many applications where reliability and power density are of importance.