Research On Constant Current And Constant Voltange Output Characteristics Of Wireless Power Transfer System

Compared with the plug-in charging,Wireless Power Transfer(WPT)power supply mode has the advantages of safety,reliability,flexibility and convenience,so it is widely used in the fields of electronic equipment,electric vehicles and medical implant devices.WPT system is extensive for the constant current or constant voltage power supply of electrical equipment,and the reasonable compensation network can not only improve the power factor and eliminate the reactive power circulation,but also realize the constant current(CC)or constant voltage(CV)output independent of the load.Therefore,realizing CC or CV output by des,igning a reasonable compensation network is one of the hotspots in the research of WPT technology.This paper introduces the resonant condition and output current or output voltage of the second-order and third-order compensating network,and then analyzes the CC or CV output characteristics of the basic low-order and high-order compensating network respectively under the premise of satisfying zero phase Angle(ZPA)by resonant tank theory.For WPT system CC output can better realize,analyzes the transconductance gain of the LC/S compensation network independent of load conditions,then studied the sensitivity of the compensating element and the implementation of ZPA and zero voltage switch(ZVS),and illustrates internal resistance of primary and secondary side coils and compensating inductors will affect the transconductance gain and transconductance gain change rate is related to equivalent load variation range and mutual inductance between primary and secondary side coils.Based on LC/S compensation network,LC/LCC compensation network with constant voltage output characteristic is proposed,then analyzes each compensation element sensitivity in secondary side ’ type resonant tank and the realization of ZPA.In order to achieve smooth current and voltage conversion between the two kinds of compensating network,compensation parameters of Γ type resonant tank is designed.Finally,two kinds of compensation network parameters are designed,and the simulation model and experimental platform are built.The simulation and experimental results verify the correctness of the theoretical analysis and the feasibility of the scheme in this paper.