Capacitively Coupled Wireless Power Transfer to Sailings Ships

A wireless power transfer system in water is studied based on the capacitive coupling in the present report. The advantage of the system is the big dielectric constant (permittivity) of water that may enhance the capacitances of the coupling capacitors resulting in the increase of power transfer efficiency. Since the conductivity of the water could deteriorate the power efficiency on the contrary, the authors compare two different structures to know the tradeoff of the big permittivity and conductivity. To avoid attenuation due to quite big conductivity, as in seawater, they are trying to cover the electrodes with insulating dielectric.