Compact Curved Coupler With Novel Flexible Nanocrystalline Flake Ribbon Core for Autonomous Underwater Vehicles

Conventionally, the magnetic core in an inductive power transfer (IPT) system is spliced by pieces of ferrites, which is time-consuming and unable to realize a seamless fit on the curved surface. This letter proposes a compact curved coupler with a novel flexible nanocrystalline flake ribbon (NFR) magnetic core. Compared with ferrite core, the NFR not only enhances the application flexibility of the IPT system but also significantly reduces its weight in certain power. Based on the LCC-S compensation topology, a 1 kW IPT prototype for autonomous underwater vehicles is fabricated. The transmission characteristics and temperature performance of the system have been investigated under three power levels, considering various permeability values for NFR cores. Finally, the NFR with a permeability of 800 is chosen as the magnetic core, and the dc-dc system efficiency reaches 92.85%. Moreover, it is possible to restrict the maximum temperature to 54.1 °C, and the weight of the NFR cores accounts for merely 4.65% of the whole coupler.