The Research Of Rf Power Supply And Impedance Matching For Wireless Power Transmission

Wireless power transmission originated from the great research of the famous scientist Nikola Tesla in the 19 th century.The technology stepped into reality after the exploration and investigation of many scientists.As a brand new power supplying method which can overcome many shortcomes of the traditional power supplying method via conductor,wireless power transmission has become the special solution of electric power supplying problem in some unique situations.With the progress of power gird’s intelligentization,the power supplying problem of high voltage apparatus has become the top priority to deal with.Compared to the common means of power supplying used on high voltage apparatus currently,the problem of potential isolation can be naturally overcome and the insulation of high voltage apparatus can be easily protected by the means of wireless power transmission.With the improving of technical means,a relative high efficiency of power transmission and a sufficient power output can be achieved in wireless power transmission system,which makes a new solution of the power supplying problem of high voltage apparatus.Aiming at solving the power supplying problem of high voltage apparatus,a power supplying plan based on wireless power transmission is proposed after analyzing the frequently used means of power supplying in this paper.A power source device whose relevant research is insufficient for wireless power transmission is designed,and the impedance matching of the power source is also finished in this paper.The specific tasks are as follows.Firstly,the magnetic resonance coupling type of wireless power transmission is selected and the frequency of 13.56 MHz is chose according to relevant standards after analyzing the frequency character of wireless power transmission system.The circuit of power source at the selected frequency is based on power amplifier.Then,the class E power amplifier is chose as the main structure of the circuit and the detail circuit parameters are calculated.The high frequency signal generator is also constructed.Moreover,the stability improving design of the transistor is conducted in Advanced Design System,and the impedance matching networks are design with Smith Chart after load-pull and source-pull simulation.Finally,a power source prototype is constructed according to the design plan and the circuit simulation.The experiment result of the prototype indicates that the prototype is able to provide a sufficient power output with a high circuit efficiency,a 47.27 dBm output power with a power-added efficiency of 77.65% is acquired in the experiment.Furthermore,some experiments of the prototype with different conditions of input signal and different load are also conducted.The experiment result shows that the prototype has the ability of adapting to some unrated working conditions.