A Misalignment-Insensitive Hybrid Reconfigurable Wireless Charging System for Constant-Voltage and Constant-Current Outputs Based on a Novel Bipolar Coil Symmetrical to Two Perpendicular Directions

The charging process of lithium-ion batteries in the wireless charging system of electric vehicles needs to go through constant-current (CC) and constant-voltage (CV) charging stages. In this article, a new reconfigurable hybrid wireless charging system is proposed to realize CC and CV outputs over a wide misalignment range. The proposed system can be reconfigured to form an input-parallel-output series connection of the inductor-capacitor-capacitor series ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LCC-</i> S) and S <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-LCC</i> topologies to achieve a CV output, or an input-series-output-series connection of the S-S and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LCC</i> - <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LCC</i> topologies to realize a CC output. Two sets of magnetic couplers are utilized, with one as the traditional unipolar coil set and the other as a novel bipolar coil set. Both coil sets can realize symmetrical misalignment performance along two perpendicular directions. Thus, the proposed hybrid system can achieve switchable CC and CV outputs and misalignment tolerance along two perpendicular directions. The mathematical model is established. The implemented prototype validates that the output voltage, output current, output power, and system efficiency are relatively stable in the vertical direction and a certain oblique range. CC and CV outputs can be achieved with the highest efficiency up to 94.52%.