Research On The Resonant State Of Wireless Power Transfer System

Wireless power transfer is a way of energy transmission between power supply and load with non-contact way.In many WPT technologies,magnetically-coupled resonant WPT has many advantages of medium transmission distance,no sensitive direction,crossing through obstacles and so on,which gradually attracted the attention of domestic and foreign scholars.Compared with the cable transmission,the WPT technology which improves the safety and reliability has a good prospect of development,so the study of magnetically-coupled resonant WPT is very significant.First,the magnetic resonance principle of WPT is described in detail.The mechanism of WPT is deeply studied based on the theory of coupled mode theory,two port theory and mutual inductance theory,to prove the consistency of the three methods.Then,based on the theory of circuit mutual inductance,the expressions of voltage gain,impedance angle,power and efficiency are derived for serial resonant-serial resonant and serial resonant-parallel resonant compensation structures,and the influence of the parameters on the resonant system transmission performance is analyzed by simulation,such as the inductance of the coil,the coupling coefficient and the frequency of the system.Finally,on the basis of the theoretical analysis and MATLAB/Simulink simulation,the experimental platform of the magnetic coupling resonant wireless transmission system is built to analyze the parameters affecting the performance of system resonant state The results show that the experimental results are well consistent with the theoretical analysis,which proves the correctness of the theoretical analysis.