Torque ripple minimization with modified comparator in DTC based three‐level five‐phase inverter fed five‐phase induction motor

Abstract

The proposed technology deals with the reduction in torque ripple of five-phase induction motor. The machine is controlled by direct torque control technique and fed by three-level five-phase inverter (TL-FPI). In the fraternity of multiphase induction motor, five phase is the most researched drive, considering complexity of control mechanism and advantages which multiphase machine has offered. The selection of TL-FPI is based on availability of more voltage vectors (243) than two-level five-phase inverter (32). The 41 voltage vectors are employed out of 243 based on simplicity and advantages of multiphase machine. The selected vectors are operated through modified seven-level torque comparator. An increase in levels of the comparator restrains the ripple in a predefined boundary. Here, modification in the predefined boundary of the comparator is suggested which allows the utilization of optimal voltage vectors. According to modification, zero voltage vectors are replaced with small active vectors when actual torque is lower than its reference value. To substantiate the claim various results of simulation and experimentation are given.