Patent ID: 7221066

Claim:
An energy supply unit for transmitting auxiliary energy for a control circuit in a medium or high voltage facility, comprising: a primary coil being at least indirectly in connection with an energy source; a secondary coil being at least indirectly in connection with a control circuit; and an insulating section installed between the primary coil and the secondary coil, over which the transmission of auxiliary energy takes place by way of a magnetic alternating field, wherein the primary coil is constructed as a flat coil and installed on a first supporting plate, and the secondary coil is constructed as a flat coil and installed on a second supporting plate, the two supporting plates being arranged at a defined distance from each other, and the insulating section is constructed as an air gap formed between the primary coil and the secondary coil, wherein an insulating plate is arranged in the air gap between the supporting plates which has a larger surface than the supporting plates, whereby the edges of the insulating plate laterally project over the edges of the supporting plates.