摘要 |
<p>A primary unit for transmitting power and/or data wirelessly by electromagnetic induction to a secondary unit separable from the primary unit, the primary unit comprising: a coil; and driving means operable to drive a fluctuating current through the coil, wherein both ends of the coil are decoupled from the driving means so that in use a voltage level at each end of the coil fluctuates with time.</p> |