Compensation topology for flat spiral coil inductive power transfer systems

Inductive power transfer technology is now widely used to provide power into various devices, such as battery based vehicles, implant devices, portable equipment etc. Despite the rapid development of power electronics components, inductive power transfer technology still has some drawbacks. The output power is vulnerable to the magnetic coupling efficiency of two coils. If misalignment and displacement of the coils occur the output power can drop sharply. This study proposes a new design that can transfer rated power at various coupling coefficients. The characteristics of the proposed topology are discussed. All discussions and conclusions are obtained for the condition that the coil self-inductance remains unchanged during misalignment. Analytical and experimental results are presented in this article, to support the proposed design.