A Study Of Adaptive Resonant Wireless Charging Technology

Recently,along with the development of the electronic technique and the control technique,the wireless power transmission(WPT)has attracted significant researchers interests.Compared with traditional wired power transfer mode,the WPT technology can release from the bondage of electric cables and realize a certain range of electric power transmission.With the advantages of convenient,safe and reliable,the WPT has obtained widespread applications in many fields,such as charging for mobile electronic devices and implantable medical devices,etc.In kinds of WPT technology,the inductive power transfer(IPT)system can achieve high transfer efficiency in medium transmitting distance with simple structures and easy to realize,so it has wide application value.However,the IPT system generally has multiple strongly interpretational parameters,which means any tiny variations of outer parameters can lead additional difficulties in control and alter the working status,like system mistuning.In allusion to the issues mentioned above,this paper presents an adaptive resonant wireless charging technology based on energy injection.In the proposed system,the energy transmission process obtained two relatively independent stages,which are energy injection stage and free resonance stage.Under the proposed scheme,the system can effectively overcome and avoid mistuning resulted from variation of system parameters.In this paper,the adaptive resonant wireless charging technology based on energy injection is introduced,and make a detailed analysis of its basic structure,work principle,and work modes.To response the variation of electrical parameters,an adaptive control scheme is designed,during the energy injection stage,the power supply independently inject energy into the primary coil,and during free resonance stage,the power supply is disconnected from the resonant network.Since the energy injection is independent,the converter frequency need not be the same as the resonant network frequency,which can reduce the switching loss.Based on the simulation software to model and simulate on the system,the system can be tuned and realize soft switching under the various load resistance and coupling coefficient,compared with traditional IPT system,this scheme reduces the difficulties of system control.Finally,the experimental platform is designed to verify the theory analysis and simulation.