Effect of Short-Circuit Voltage Profile on the Transient Performance of Saturated Permanent Magnet Synchronous Motors

When permanent magnet synchronous motors are subjected to short-circuit at their terminals, the accurate calculation of the motor transient performance depends on the short- circuit voltage profile and the saturation condition of the main flux paths. In this paper, a voltage profile due to a short-circuit at the motor terminals is proposed where the motor terminal voltage requires a certain period of time to fall to zero value and, following the clearing of the fault, the terminal voltage also requires a certain period of time to recover to a post-short-circuit value. Three models of permanent magnet synchronous motors have been developed to demonstrate the effect of the main flux saturation on the determination of the transient performance of permanent magnet synchronous motors employing the proposed short- circuit voltage profile.