A Stable Dynamic Wireless Charging System Based on Triple Decoupling Coils and a Novel Three-Phase Rectifier with Reduced Diode Number

In electric vehicle (EV) dynamic wireless power transfer (DWPT) systems, changes in the mutual inductance will lead to fluctuations in the output voltage and efficiency. In this paper, a novel three-phase rectifier that can reduce the number of diodes is proposed, with each phase connected to one of the triple decoupling coils (TDC) on the receiving side. Decoupling is achieved with partial overlapping. Reverse windings are integrated into TDC to smooth the mutual inductance fluctuations. The proposed novel rectifier switches between the single-coil receiving mode and the dual-coil receiving mode in response to the different positions of the EV. The proposed magnetic coupler structure and the novel rectifier guarantee a constant output during movement. The effectiveness of the proposed DWPT system has been verified by the experimental prototype. The output voltage remains stable over a long range, with a fluctuation only about 2.23%. The proposed DWPT system can not only reduce the number of track coils but also extend the novel three-phase rectifier to multi-phase with a reduced diode number, which has good reference value.