Harmonic Current Suppression in Modular Multi‑Sector PM Machines via Virtual Current Reconstruction

This letter proposes a low-frequency harmonic current suppression method for modular multi-sector permanent-magnet machines based on virtual current reconstruction. Unlike conventional approaches that require additional controllers or complex parameter tuning, the proposed scheme utilizes the inherent harmonic decomposition capabilities of modular multi-sector architectures to facilitate harmonic current suppression. The currents of three sectors are phase-shifted by 15°, 30°, and 45° electrical degrees with respect to a reference sector, forming a virtual quadruple three-phase machine with angle displacements. The reconstructed currents are further processed using vector space decomposition, which separates the fundamental and harmonic components, and enables independent regulation of each subspace using only proportional-integral controllers. Experimental validation on a modular four-sector machine confirms the effectiveness of the proposed method.