An Integrated Inductive–Capacitive Nanocrystalline Core for Compact Inductive Power Transfer Systems

Nanocrystalline magnetic cores have been increasingly adopted in inductive power transfer (IPT) systems, due to their high saturation flux density, lightweight, and design flexibility. However, the high conductivity of nanocrystalline materials leads to increased eddy current losses, which has been a drawback in high-frequency applications. This letter proposes a novel concept of the integrated inductive-capacitive core (IICC) structure, which takes advantage of the high conductivity characteristics of nanocrystalline materials and the distinctive laminated configuration of the nanocrystalline core to build the resonant capacitor required in an LC resonant tank. The structural design of resonant capacitors based on laminated nanocrystalline cores is described in detail. Furthermore, LCR resonance experiments demonstrate that the electric and magnetic fields within IICC are decoupled, and the breakdown voltage of the nanocrystalline capacitor is comparable to that of commercial capacitors at more than 500 V. A 300 W IPT prototype based on the S-S compensation topology is fabricated to verify the feasibility of IICC.