Remedial control strategies for a three-phase PM BLDC drive under VSI faults

This paper analyzes the torque performance achievable from a three-phase PM BLDC drive under a fault of the VSI supplying the motor. Various types of fault are considered such as one leg open, one switch open and one switch shorted. Remedial control strategies for the healthy devices of the VSI are envisaged, that make the drive operating even if in a degraded way. The resulting torque performances are calculated in terms of developed torque and torque ripple. The mathematical findings are substantiated with graphs obtained by simulation on an in-wheel PM BLDC drive used for the propulsion of light electric vehicles.