Analysis And Design Of The Charging Platform Based On Non-contact Power Transmission System

In recent years, with the popularity of mobile phones, MP3, tablet PCs and other small portable electronic digital products, the requirement and application of charging device are increasing. However, in general condition, each device requires a matching charging device which will result in a large waste of resources and disobey with the electronic products’original design intention of small size and portability. Under this circumstance, the wireless charging technology goes into people’s vision. Non-contact charging is a kind of technology which is based on electromagnetic induction, electromagnetic resonance or radiation and it has some advantages such as a wide scope of application and convenience to use. Nowadays, the application domain of non-contact charging technology is expanding and its demand is increasing rapidly.In the real application scenario, however, the charging transmission distance and charging efficiency have been the impact bottlenecks of non-contact charging technology’s development. For the above reasons, this thesis analyzes the main factors which influence the non-contact power transmission efficiency and transmission distance. And a preliminary study is carried out to analyze the relationship between the transmission efficiency and the transmission distance, and the impact of the relative position of coils on the transmission efficiency and the transmission distance is also provided. In order to ascertain the constraints of non-contact charging technology’s charging effect, STC12C5A60S microcontroller is used as the control core, and the transmitting circuit, rectifying circuit, display circuit and other peripheral circuits are also designed and implemented to develop a charging platform based on non-contact charging system. Then based on the platform, system research and analysis are carried out to defmitize the relationship between device’s terminal voltage and distance, and the relationship between charging efficiency and radius of the charging coil, coils’relative distance and the value of load resistance. Conclusions are drawn as follows:(1) Charging an object is directly inverse proportional to the voltage across the charging transmission distance, and with the transmitting and receiving coil distance increases, the voltage at the output is reduced;(2) Increasing the radius of the transmitter and receiver coils can improve the efficiency of wireless power transmission;(3) As the distance between the transmitting and receiving coil increases, the transmission efficiency is improved;(4) When the value of load resistance is within a certain range, the wireless power transmission efficiency is improved as the load increases.