Inductive power transmission technology (IPT), which transfers power through magnetic coupling, is safer, more flexible and more convenient, compared to plug-in power transfer solutions. It has fund more and more applications, such as personal electronic devices, wearable/implantable electronics, electric vehicles, and so on. A lot of effort has been put to improve the performance of the power transmission, including efficiency, controllability and misalignment tolerance. In addition to the power transmission issues, how to solve the safety and the positioning problems in practical applications is also an urge problem for an IPT system. Without positioning system, it is very different to satisfy the allowable misalignment range for a wireless coupler. The existence of foreign objects may cause overheating and safety problems. To solve abovementioned problems, auxiliary functions including coil positioning, foreign and living object detections have been specified as an essential part for some IPT applications, for example, a commercialized wireless EV charging system.
In this presentation, the auxiliary function requirements of an inductive power transmission system as well as the related technologies will be given. Firstly, a brief introduction of the introducing reason and the requirements of the auxiliary functions, will be presented. Secondly, we will discuss the feasible solutions and the main issues of the position technologies for IPT systems. And then, several foreign object and living object detection methods will be introduced as well as their limitations. Lastly, the information security issues will be mentioned.