Energy supply unit for transmitting auxiliary energy to an electrical device

An energy supply unit includes a primary coil which is at least indirectly connected to an energy source. In a secondary coil which is at least indirectly connected to the control circuit, and an insulating section formed between the primary coil and the secondary coil. The auxiliary energy is transmitted via the insulating section by way of a magnetic alternating field. The energy supply unit further includes a first carrier plate, a primary coil embodied as a flat coil situated on the first carrier plate, a second carrier plate, and a secondary coil embodied as a flat coil situated on the second carrier plate. The insulating section is embodied as an interferric space formed between the primary coil and the secondary coil.