Virtual Subspace-Based DTC Strategy for Torque Ripple Minimization in Six-Phase Induction Motors
Classical switching-table-based direct torque control (ST-DTC) of six-phase induction machine (6PIM) drives is seriously penalized by current harmonics as well as torque ripples because of uncontrolled voltage vectors in the low-impedance non-energy subspace and hysteresis torque regulator, respecti...
Guardado en:
| Autores principales: | , |
|---|---|
| Formato: | article |
| Lenguaje: | EN |
| Publicado: |
IEEE
2021
|
| Materias: | |
| Acceso en línea: | https://doaj.org/article/b4e963e02c774037a18b7f79fdd11659 |
| Etiquetas: |
Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
|
| Sumario: | Classical switching-table-based direct torque control (ST-DTC) of six-phase induction machine (6PIM) drives is seriously penalized by current harmonics as well as torque ripples because of uncontrolled voltage vectors in the low-impedance non-energy subspace and hysteresis torque regulator, respectively. Hence, a virtual subspace-based DTC strategy is proposed to alleviate the impact of low-order current harmonics and torque ripples. The proposed virtual subspace includes 48 virtual voltage vectors (VVs) in the <inline-formula> <tex-math notation="LaTeX">$\alpha -\beta $ </tex-math></inline-formula> subspace with average volt-seconds of zero in the <inline-formula> <tex-math notation="LaTeX">$z_{1}-z_{2}$ </tex-math></inline-formula> subspace, which offers full extent of freedom degrees for 6PIM fed by a two-level voltage source inverter (VSI). The increased number of VVs allows the possibility to design up to nine-level hysteresis torque regulator to minimize the torque ripples. Nevertheless, in this paper, it is found that torque ripple, current harmonics, average switching frequency, and computational burden come to a compromise with a seven-level hysteresis torque regulator. The impact of these VVs on the performance of ST-DTC is experimentally studied and some details of hardware implementation are presented. The performance of the proposed scheme is verified by simulations as well as laboratory experiments, where a complete comparison with recent schemes is made to reveal the superiority of the proposed scheme. |
|---|