Analysis Of Energy Efficiency Characteristics In Magnetic Coupling Resonant Wireless Power Transmission System

Wireless power transmission(WPT)is a technology,which can transfer power with electromagnetic fields.At present,there are three main types of WPT technologies: electromagnetic inductive coupling WPT,magnetic coupling resonance WPT and microwave WPT technology.Among them,magnetic coupling resonant WPT technology has become the focus of researches in recent years because of its advantages in transmission distance,transmission penetration and security.Based on LCC-S type resonant circuit,the follow reaches of magnetic coupling resonant WPT have been finished:(1)The main parts of magnetic coupling resonant WPT system and its three main theories-magnetic resonant theory,magnetic coupling theory and mutual inductance coupling circuit model,are introduced.Base on mutual inductance coupling model,the equivalent circuit of magnetic coupling resonant wireless power transmission system is built.(2)Based on the equivalent circuit model,the advantages and disadvantages of the LC resonant circuit of series-series(SS),series-parallel(SP),parallel – series(PS),and parallel – parallel(PP)four structures,and LCC-S type resonant circuit are analyzed theoretically.Then,the effects on system transmission characteristics by the changes of system working frequency,transmission distance and load quality factor are studied in values of resonance topologies that mentioned before,and the conclusion of LCC-S resonant circuit with constant current output is obtained.After that,the simulation model of LCC-S type magnetic coupling resonant WPT system is built by MATLAB/SIMULINK,which verified the characteristic of constant current output on LCC-S type resonant circuit in simulation.(3)The hardware of magnetic coupled resonant WPT system is designed after selecting suited circuit topology and device model.Based on this equipment,the no – load,half load,75% of rate load and full load researches of system are finished.The research results show that the LCC-S type magnetic coupling resonant WPT system has an higher efficiency in wireless power transmission and constant current output characteristic.