Fault Tolerance of Dual-Three-Phase Drives: Tuning of the Auxiliary Current Regulators and Open-Phase-Fault Operation

This paper analyzes the intrinsic fault tolerance of dual-three-phase permanent magnet machines during an unexpected open fault scenario. The model of the drive system, developed by means of vector space decomposition approach, is introduced at first. It is shown how the main space vector is used to control flux and torque, while the auxiliary vector aims to limit current distortion and maintain a balanced distribution of power between the two winding sets. After, the fault operation is analyzed considering one phase opened. In this study, no postfault strategies are implemented, assuming that when the fault happens the monitoring system is not implemented or fails to detect the drive fault. In other words, the intrinsic fault tolerance of the drive is investigated.