Patent ID: 7076206

Claim:
A system for wireless transmission of electrical energy comprising at least a first induction element ( 12 ) that is connected to a primary circuit (P), and at least a second induction element ( 14 ) that is connected to a secondary circuit (S), in which the induction elements ( 12 ), ( 14 ) can move position in relation to each other and are able to be positioned so that they are magnetically coupled, wherein in the primary circuit (P) means ( 32 ) for supplying the first induction element ( 12 ) with an AC voltage are provided for, so that in the first induction element ( 12 ) a magnetic field is generated, wherein a voltage is induced in the secondary circuit (S) as a result of the magnetic coupling with the second induction element ( 14 ), characterized in that in the primary circuit (P) means for setting the frequency of the AC voltage are provided, wherein responsive to an information signal representative of a change in degree of magnetic coupling between the first and second induction elements and thus a corresponding change in resonance in the primary circuit (P), the AC voltage frequency setting means changes an excitation frequency of the AC voltage supplied to the first induction element to make specific use of the change in resonance resulting from positional or locational changes of the induction elements in relation to each other.