Patent ID: 8878392

Claim:
An inductive power transmitter for transmitting electrical power to a device by electromagnetic induction, the transmitter being configured to receive power conductively by way of a current via an electrical conduit from an external power source, the transmitter comprising: a field generator configured to generate a fluctuating electromagnetic field having a fundamental frequency; and at least one impedance element connected along an electrical path of the transmitter configured to carry said current, the at least one impedance element having a high enough impedance at the fundamental frequency such that, in use, electromagnetic noise experienced at the power source is substantially suppressed, such noise arising from coupling between the electromagnetic field and a circuit having said path and linking the power source to the transmitter, wherein the at least one impedance element includes first and second inductors, wherein a voltage induced by the field generator in the first inductor opposes a voltage induced by the field generator in the second inductor.