A New Sensorless Control of Flux-Switching Permanent Magnet Machine Based on Magductance Saliency

Abstract

In most cases, the saliency ratio (L_q/L_d) of flux-switching permanent magnet (FSPM) machines is low because the field modulation effect brings small equivalent reluctance saliency. Thus, it hinders the sensorless control dependent on reluctance saliency. To solve this problem, a novel magductance saliency, the difference between magductance of d-axis and that of q-axis, is introduced through adding short-circuited coils in the stator of FSPM machine. Consequently, the saliency ratio of FSPM machines is increased. Additionally, the issue of multiple saliencies presents a significant drawback, negatively impacting the performance of sensorless control, especially when the machine has a low-saliency ratio. Thus, the position observer based on second-order generalized integrator frequency locked loop (SOGI-FLL) is applied to solve this problem. Finally, the proposed method is validated on a 6-stator-pole/19-rotor-tooth FSPM machine, demonstrating its effectiveness.