Misalignment-Tolerant IPT Coupler With Enhanced Magnetic Flux Variation Suppression and Reduced Copper Usage

Misalignment tolerance is essential in the design and implementation of inductive power transfer (IPT) systems. This article proposes an IPT coupler, termed the rectangular-solenoidal pad (RSP), which combines a rectangular coil and a solenoidal coil. The proposed RSP can effectively capture both vertical and horizontal magnetic fields, complementing each other to suppress magnetic flux variation during misalignment. Compared with the commonly-used double-D quadrature pad, the proposed RSP achieves the same level of magnetic flux variation suppression with less coil wire, making it more misalignment-tolerant with the same amount of copper. To optimize the design for misalignment tolerance, a quick approximation method for designing the solenoidal coil is developed to eliminate the need to simulate mutual inductances across the entire range of misalignment during coil design. A 1-kW experimental prototype is built to validate the proposed design.