Fault-Tolerant and Voltage Balancing Control for Five-Phase Three-Level T-type Inverters under Open-Switch Faults

The reliability of the system is a demanding challenge in many application fields, such as automotive, aerospace, renewable energies, and other industrial applications. Multiphase machines and drives suit this request due to their inherent fault-tolerant capability. However, to allow post-fault operation, a dedicated control technique must be developed. Multilevel converters improve the performance of the machine in terms of currents and torque ripples. Moreover, the multilevel converters provide many degrees of freedom to the system and are more flexible during an Open Phase Fault (OPF) or Opens Switch Fault (OSF). In this paper, a fault-tolerant technique for five-phase three-level T-type inverters under Open Switch Fault is developed. The OSF is analyzed while considering the voltage balancing of the dc-bus capacitors. Some simulation results are provided to verify the feasibility of the proposed solution.