Range adaptation of Wireless Power Transfer systems for biomedical applications

The circuit components of a Wireless Power Transfer (WPT) system are designed considering a fixed separation distance and fixed alignment between the transmitting and receiving sides of the WPT system. But, in practice, the separation distance and the alignment do not remain constant. This is especially true for a biomedical application where a moving instrumental part requires electric power. This change causes a variation in mutual coupling and consequently in the efficiency of the system. This paper describes how to maintain the efficiency more or less constant even if the separation distance and the alignment vary. First of all, the circuit elements for maximum efficiency are worked out, then simulation for various separation distances and misalignment are calculated. A means of controlling a particular parameter is worked out in order to maintain efficiency of the system more or less constant.