Recent Advances in Underwater Energy Systems and Wireless Power Transfer for Autonomous Underwater Vehicle Charging

In recent years, the need for autonomous underwater vehicles (AUVs) for offshore infrastructure maintenance and oceanographic surveillance has been prominently increasing. Continuous monitoring and surveillance are the essential tasks the AUVs are designed to perform. However, the long endurance of the AUV is a challenging task due to the limited size and capacity of the onboard battery. The conventional way of recharging using battery swapping or a wet mate connector limits the autonomy of the AUV. Underwater wireless power transfer (UWPT) technology seems to be a suitable alternative for overcoming the above limitations, which can provide autonomy to the AUV charging process. However, designing a UWPT system has its limitations in the marine environment and requires enough engineering studies of the different modules of the system. Different investigations are proposed in the literature on the UWPT system, both at the system level and circuit level. This article provides an overview of the latest advancements in the UWPT system and discusses marine power sources, power converter topologies, compensation topologies, and different types of magnetic couplers. The article also discusses the engineering challenges in designing a UWPT system, including eddy current loss and biofouling. The article also summarizes current research trends, potential challenges in UWPT, and future technological developments from prototypes to practical products and offers recommendations for further progress.