Phase Current Reconstruction for Dual Three-Phase PMSM With Hybrid Zero-Vector Modulation Strategy

Phase current information is critical for dual three-phase permanent magnet synchronous motor (DTP-PMSM) drive, but conventional multi-sensor solutions increase system bulk and cost. This paper proposed a current reconstruction method for DTP-PMSM with a hybrid zero-vector modulation strategy, in which only two current sensors are adopted. First, a low-complexity placement scheme for the two current sensors is proposed, enabling the acquisition of four-phase currents with them. Second, a novel hybrid zero-vector modulation strategy is employed to facilitate the reconstruction of six-phase currents within a single pulse-width modulation cycle. The proposed modulation strategy can not only achieve accurate current reconstruction in the low modulation region but also eliminate dead zones at sector boundaries. Also, the current sampling delay and the residual dead zone of the current reconstruction are analyzed. Experimental results validate the effectiveness of the proposed control strategy.