Topology and inductance analysis for wireless power transmission system

Factors that affect transmission efficiency of resonance based wireless power transmission (WPT) is discussed in this paper. Two topologies of input circuit of WTP system are analyzed; Comparison of the two topologies is given on capability of output exiting current for resonance coils with angular frequency changing from 0 to 20 MHz. Mutual induction between resonance coils is given in mathematical expression which shows that the mutual induction of resonance coils is changing with modulus value of coils and the angular frequency of the system. One way of impedance matching by changing inductive coupling coefficients between exiting coil and resonance coil is introduced. Experiment of WPT is introduced and the experiment results match well with the calculating result, the system performs well in delivering power using magnetic resonance coupling which shows that methods provided in this paper have practical guiding on building four coils WPT system.