Analysis and Design of a Wireless Charger for Underwater Vehicles Fed from a Constant Current Distribution Cable

Existing conductive power supplies for undersea electronic systems are typically fed from constant low-current distribution with a seawater return. In such systems, power converters are connected in series along the distribution cable to supply power to sensor loads and underwater vehicles. Isolated voltage fed resonant converters are often used for the advantages of soft-switching and low component stress. When supplying underwater vehicles, there is further motivation to develop a wireless solution to improve reliability by removing the seawater exposed contacts. This can be accomplished by replacing the isolation transformer of existing resonant converters with series-series compensated coupled coils to create an inductive power transfer (IPT) solution. The introduction of the IPT system changes many factors in the design that need to be considered. This paper presents detailed analysis and design of wireless charger for underwater vehicles fed from a constant current distribution cable. The design is validated with experimental results for a 330 W prototype supplied from a 1 A source operated underwater with a switching frequency of 250 kHz.