An Electric-field Coupled Power Transfer System With Constant Voltage And Constant Current Output Based On Changeable LC-CLCL Resonant Circuit

Wireless power transfer(WPT)technology refers to the non-contact transmission of electric energy with the help of space soft media(such as magnetic field,electric field,microwave,laser,ultrasonic,etc).This mode of power supply avoids the shortcomings of traditional power supply mode,such as plug-in and plug-out spark,poor flexibility and so on.It has received great attention since Tesla proposed.Electricfield coupled power transfer(ECPT)technology is one of the wireless power transfer technology,which has been studied and applied extensively.It takes high frequency alternating electric field as an energy medium to transfer power from the grid or power source to load wirelessly.Its advantages include light weight,no eddy current losses in the metals nearby the system,power transfer capability through metal barriers and so on.It has gradually attracted the attention of research teams at home and abroad.In order to use the ECPT system to charge the battery load with constant voltage and constant current,this paper proposes a variable structure LC-CLCL topology electric field coupling power transmission system,which can realize the constant voltage or constant current output when the load changes,which has great significance to the stable charging of battery load.Firstly,this paper analyzes the research status of ECPT system at home and abroad,and analyzes the main methods to achieve constant output.Then,Composition of ECPT has been analysed,first order,second order,third order have been focused on.The parameter conditions of constant output of each resonant network are obtained.Furthermore,the characteristics of the system under constant current,constant voltage and no-load mode are analyzed,and the realization conditions of constant voltage and constant current are established.The equivalent mathematical model is established for each part of the system,On this basis,Then,the system characteristics of constant current,constant voltage and no-load mode are analyzed,and the conditions of constant voltage and constant current are established,which can ensure that the system automatically enters the low power consumption state when the load is cut off,Based on these,The design method of system parameter has been proposed,the load range and transmission efficiency of the system are analyzed.Finally,a system simulation model is set up in MATLAB/Simulink software.According to the proposed method,a set of system parameters are obtained,the output voltage and current of the system are simulated.The results show that the system can maintain stable output and work in zero phase angle(ZPA)state.At the same time,when the load is cut off,it can automatically enter the low-power state,which has load adaptability.the experimental system and simulation are built to realize the constant current output of 1A and the constant voltage output of 50 V under the condition of constant input voltage,which verifies the validity and correctness of the method proposed in this paper73 figures,10 tables and 85 references are included in this paper.