Design of Conductive Coupler for Underwater Wireless Power and Data Transfer
Masaya Tamura, Kousuke Murai, Marimo Matsumoto
Abstract
Realizing capacitive coupling under seawater is difficult, although the capacitive coupler attracts attention as a promising solution for wireless power and data transfer. The coupler consisting of parallel-plate electrodes (e.g., capacitive coupler) has strong conductive coupling because of the high conductivity of seawater. This study introduces the design of a highly efficient coupler utilizing this phenomenon as a novel method. First, the operational principle of the highly efficient conductive coupler is clarified by comparing it to a conventional conductive coupler. The results reveal the key factor for the high-efficiency design. The design parameters at the maximum available efficiency are derived. The designed coupler is then fabricated. A demonstration shows that the efficiency of over 90% under seawater is achieved at a 20-mm transfer distance and a 1-kW transfer power. The demonstration also shows that power is wirelessly transferred to a camera module via the coupler, with the transferred data recorded by the camera appearing on a laptop computer.