A Sensorless Control Method for an Open-Phase Five-Phase PMSM by Using Series-SOGI and an Adaptive Neutral-Voltage Compensation

Upon the occurrence of an open-phase fault in a five-phase permanent magnet synchronous motor (5Ph-PMSM), a disruption in the balance of the remaining healthy phase currents is observed, resulting in the introduction of second and fourth harmonics into the position estimation. To address this challenge, the current study proposes an innovative sensorless control approach specifically for open-phase 5Ph-PMSM systems. This methodology integrates series second-order generalized integrators (series-SOGIs) to effectively mitigate the undesirable harmonics and extract the positive sequence component from the distorted back electromotive force (EMF). Additionally, an adaptive neutral-voltage compensator is implemented to alleviate the asymmetry present in the back-EMF, thereby further enhancing the precision of the sensorless control. The effectiveness of the proposed methodology is corroborated through rigorous experimental results.