Control of a PMSM With Quadruple Three-Phase Star-Connected Windings Under Inverter Short-Circuit Fault

This paper proposes a novel approach for the control of a permanent magnet synchronous machine with a quadruple three-phase star-connected winding configuration after a short-circuit (SC) fault in one voltage source inverter. The approach includes an adaption of the closed-loop current control that allows operation of the faulty unit to proceed without the need to adapt the reference currents. This allows an operation of the faulty drive with increased postfault mean torque. Additionally, a strategy for postfault torque error compensation is proposed, which can be used to reduce the torque ripple while the load distribution is better balanced. Results are respectively compared to the case when applying a symmetric SC to the faulty unit, which is the conventional strategy in case of a transistor SC fault. The current limit of the drive is considered in all cases. The benefits of the approach are validated through experimental tests.