High-Misalignment-Tolerant Dual-Channel Inductive Power Transfer System Based on Cross-Shaped Reversed-Winding-Incorporated Solenoid Pad

Abstract

The inductive power transfer (IPT) system needs to have a stable output even when the coil offset occurs. In this article, a combination of a square coil and a novel cross-shaped solenoid pad with reverse windings is proposed. The former is used to pick up the vertical magnetic flux, and the latter is to receive the horizontal magnetic flux generated in the offset case to compensate for the decrease in the vertical magnetic flux. A dual-channel inductor-capacitor-capacitor-series topology with series connected diode rectifiers is utilized to form two energy transfer channels with opposite misalignment characteristics to achieve a stable output. The proposed magnetic couplers can achieve a smooth mutual inductance fluctuation in both the horizontal <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">X-</i> and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Y</i> -directions. The fluctuation of the equivalent total mutual inductance is 4.35% from −210 to 210 mm (52.5% of the pad size) in both directions. An experimental prototype is built to verify the stability of the proposed IPT system. The experimental results show that within the 52.5% offset range of the pad size, the output voltage fluctuates by only 4.52%. A stable output can be obtained when the pad is offset from 90 to 140 mm in the vertical direction and the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">XOY</i> plane.