Open-phase fault operation of 5-phase induction motor drives using DTC techniques

Direct torque control (DTC) is extensively used in conventional three-phase drives as an alternative to field-oriented control methods. The standard DTC technique was originally designed to regulate two independent variables using hysteresis controllers. Recent works have extended the procedure for five-phase drives in healthy operation accounting for the additional degrees of freedom. Although one of the main advantages of multiphase machines is the ability to continue the operation in faulty conditions, the utility of DTC after the appearance of a fault has not been covered in the literature yet. This paper analyses the operation of a five-phase induction motor drive in faulty situation using a DTC controller. An open-phase fault condition is considered, and simulation results are provided to study the performance of the drive, comparing with the behavior during healthy state.