Abstract: A device for inductively transmitting electrical energy between a power supply unit arranged on the shore of a body of water or in the body of water and a watercraft includes a primary coil associated with the power supply unit, and a secondary coil which is connectable to the primary coil for inductively transmitting electrical energy, and which is arrangeable on the watercraft. A height-adjustment device connected to the primary coil is provided in order to hold the primary coil at a consistent vertical distance from a water surface in a vertical direction running in the direction of the buoyancy. A corresponding charging system and method includes: aligning the coils relative to one another; previously or simultaneously adjusting a vertical distance between the primary coil and water surface by with a height-adjustment device; inductively transmitting electrical energy between the coils.

Abstract: A method for detecting an electrically conductive foreign body on a primary coil of an inductive charging station for an electric vehicle using a plurality of measuring inductances, which are arranged, on the primary coil side, in distributed fashion, in the area of the primary coil, facing, during operation, a secondary coil of the electric vehicle, over the cross section of the field region of the primary coil. A plurality of consecutive measurements of different groups of measurement inductances is carried out. Each measurement on a group of measurement inductivities is carried out simultaneously for all the measurement inductances of the group. The measurement inductances of each group are separated from one another by a predetermined minimum distance, which is selected so that the crosstalk between the measurement signals of the individual measurement inductances of each group remains below a predetermined threshold.

Abstract: In a coil unit of a device for inductive transmission of electrical power with a cover, a base and a coil arranged between the cover and base. During operation of the device, the cover faces another coil unit and the base faces away from it. At least one support element, which mechanically supports the cover on the base, is arranged between the cover and the base. At least one cavity is formed between the cover and the support element by protrusions on the cover and/or on the support element, whereby the cover lies on the support element, and/or at least one cavity is formed between the base and the support element by protrusions on the support element and/or on the base, whereby the support element lies on the base. Sensors or elements for magnetic flux guidance can be arranged protected from mechanical load in such a cavity.

Abstract: A method for detecting an electrically conductive foreign body on a primary coil of an inductive charging station for an electric vehicle using a plurality of measuring inductances, which are arranged, on the primary coil side, in distributed fashion, in the area of the primary coil, facing, during operation, a secondary coil of the electric vehicle, over the cross section of the field region of the primary coil. A plurality of consecutive measurements of different groups of measurement inductances is carried out. Each measurement on a group of measurement inductivities is carried out simultaneously for all the measurement inductances of the group. The measurement inductances of each group are separated from one another by a predetermined minimum distance, which is selected so that the crosstalk between the measurement signals of the individual measurement inductances of each group remains below a predetermined threshold.

Abstract: In a coil unit of a device for inductive transmission of electrical power with a cover, a base and a coil arranged between the cover and base. During operation of the device, the cover faces another coil unit and the base faces away from it. At least one support element, which mechanically supports the cover on the base, is arranged between the cover and the base. At least one cavity is formed between the cover and the support element by protrusions on the cover and/or on the support element, whereby the cover lies on the support element, and/or at least one cavity is formed between the base and the support element by protrusions on the support element and/or on the base, whereby the support element lies on the base. Sensors or elements for magnetic flux guidance can be arranged protected from mechanical load in such a cavity.