All Electric Ship electromagnetic signature. A twenty megawatts podded ship

Abstract

Today, many ships, cruise liners and Navy vessels, use an electric podded propulsion. These "All Electric Ships" (AES) need an important electric power. Consequently, high currents in extremely low frequencies (ELFE), flow through cables and equipment. These alternative currents could generate important underwater electromagnetic field. We have to quantify the level of this field and its impact on the signature of this kind of ship. Then, GESMA carried out electromagnetic measurements using a multisensors underwater and autonomous facility named AMI. It was placed on the route of a few megawatts podded ship, at one hundred meters depth from the surface. We observed a non negligible radiated electric field.