Quantitative analysis of wireless power transfer system with ferrite cores

As early as in the nineteenth century, American physicist and engineer Nikola Tesla had designed and experimented a long range wireless power transfer system - the Wardenclyffe Tower [1]. Unfortunately, the project was not completed because of insufficient funding. Subsequently, the possibilities of microwave power transmission were explored by William C. Brown in 1961 [2]. Since the new century, the technology of wireless power transfer has received increasing attentions from all over the world because of its intrinsic safety and convenience characteristics. In this paper, the wireless power transfer system being used is a deep brain stimulator which is implanted in the patient´s brain . A novel shape of transmitter coil as shown in Fig . 1 (b) is proposed . In this system, the transmitter coil uses a core which has an arc along the shape of the head . For deep brain stimulator, the receiver coil should be as small as possible . In order to realize maximum power transfer efficiency, the ferrite core being inserted into the transmitter coil is optimized .