Six-phase induction motor (6PIM) drives offer enhanced fault tolerance and reduced per-phase ratings. Hysteresis current control (HCC) is attractive for 6PIMs because it is simple, robust and fast. HCC is conventionally implemented so that each leg voltage is directly set based on the respective phase-current error. However, this approach does not consider that, in multiphase drives, phase voltages and currents are related through a combination of equivalent impedances corresponding to various subspaces. In general, there is a notable dissimilarity between these impedances, being typically small for secondary ( xyxy ) subspaces. This can cause large current distortion and poor reference tracking. This article proposes an improved HCC for 6PIM drives. Instead of directly inputting the per-phase current error to the hysteresis comparator and directly applying the switching states chosen by it, the input and output components associated with different subspaces are segregated. The input and output xyxy components are nullified in open loop so that the xyxy impedance no longer affects the HCC behavior, even if low. This prevents the disrupting xyxy currents, ensures effective tracking of the torque/flux-producing αβαβ reference current, and enables reconfiguration-less fault tolerance. Experiments using 6PIMs with different winding configurations corroborate the significant advantages of the proposal.
Bibliographical noteKAUST Repository Item: Exported on 2023-09-11
Acknowledgements: This work was supported in part by ITIDAs ITAC collaborative funded project under the category type of advanced research projects (ARP) and Grant ARP2020.R29.7, in part by the Government of Galicia under Grant ED431F 2020/07 and Grant GPC-ED431B 2020/03, in part by the Ministry of Science, Innovation and Universities under the Ramon y Cajal Grant RYC2018- 024407-I, and in part by Spanish State Research Agency (AEI) under project PID2022-136908OB-I00/AEI.
ASJC Scopus subject areas
- Control and Systems Engineering
- Computer Science Applications
- Electrical and Electronic Engineering