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To significantly reduce switching loss of the high frequency inverter in battery wireless charger (BWC), improve the soft-switching stability and system reliability, a novel soft-switching BWC with low loss auxiliary network and reconfigurable rectifier is presented. The presented soft-switching BWC can implement the smooth switching between constant current mode and constant voltage mode without frequency switching and relays, which is beneficial to enhancing the system stability. With the help of a novel low energy consumption auxiliary circuit, the power switch tubes in the H-bridge inverter can implement zero-voltage soft switch-on and zero-current soft switch-off in the full range, completely eliminating switching loss of the inverter. The proposed scheme can enhance the system efficiency while refraining from the soft-switching range limitation and soft-switching failure caused by the system parameter perturbation. Finally, a 1-kW soft-switching BWC principle prototype is developed to validate the effectiveness and correctness of the proposed scheme.

Five-phase open-end winding permanent magnet synchronous motor (OEW-PMSM) fed by a dual inverter has gained increasing focus because of its advantages in voltage utilization, torque density, and reliability. In this article, an optimized modulation method with the sliding clamped strategy is proposed for the five-phase OEW-PMSM drive with a common dc bus. The conventional clamped strategies have a reduced switching sequence. However, the clamped inverter generates the zero-sequence voltage and third harmonic voltage, which would affect the performance of the motor. To solve this problem, the reference voltages in the proposed method are distributed by limiting the reference voltage of the clamped inverter on a line. And the reference voltage slides on this line bidirectionally. Therefore, the clamped inverter in the proposed method will not introduce additional harmonic components. For experimental verifications, the test results are presented with the resistance-inductance load and five-phase OEW-PMSM.