Current Reconstruction for Dual PMSMs Fed by a Five-Leg Voltage Source Inverter With a Single Current Sensor

The dual-motor system driven by five-leg voltage source inverter (FL-VSI) has been widely studied as a better fault-tolerant scheme. In this paper, a phase current reconstruction strategy based on a single current sensor is proposed to realize the phase currents reconstruction of the dual permanent magnet synchronous motors (PMSM). Firstly, the FL-VSI adopts a centralization modulation strategy to realize independent control of the two motors while expanding the speed range of the motors. Then, a pulse shift strategy applied for the dual-PMSMs system driven by FL-VSI is proposed. The phase currents can be reconstructed when two motors are running in the low modulation region, sector boundary region, or the new phase current reconstruction dead zone by the proposed method. The experimental results show that the reconstructed phase currents can always be consistent with the actual phase currents, which proves the feasibility and effectiveness of the proposed method.