Implantable wireless power system

Abstract

A wireless power system capable of transmitting power through the skin without percutaneous wires over distances ranging from a few inches to several feet includes an external transmitting coil assembly and a receiving coil assembly. The transmitting coil assembly includes an excitation coil and transmitting resonant coil which are inductively coupled to each other. The receiving coil assembly includes a receiving resonant coil and a power pick-up coil which are also inductively coupled to each other. A high frequency AC power input, such as radio frequency (RF), supplied to the excitation coil inductively causes the transmitting resonant coil to resonate resulting in a local time varying magnetic field. The transmitting and receiving resonant coils are constructed as to have closely matched or identical resonant frequencies so that the magnetic field produced by the transmitting resonant coil is able to cause the receiving resonant coil to resonate strongly also, even when the distance between the two resonant coils greatly exceeds the largest dimension of either coil. The receiving resonant coil then creates its own local time varying magnetic field which inductively produces a voltage in a power pick-up coil to provide power to an active implantable medical device or implantable rechargeable battery.