Comparison of Fault-tolerant control strategies for a nine-phase IPMSM-FSCW

This paper presents a comparison of two fault-tolerant control strategies in order to ensure a good performance after an open-phase fault. The analysed strategies are Minimum Losses (ML) and Maximum Torque (MT), which are compared analytically and in simulation, in terms of stator copper losses and achievable torque. This analysis has been carried out under two different conditions: maintain post-fault torque as in pre-fault operation or maintain post-fault phase current under the rated value. Both fault-tolerant control strategies have been validated and compared in Matlab/Simulink tool in the full speed operation range, considering a nine-phase IPMSM with symmetric and Fractional Slot Concentrated windings (FSCW).