Simulation and Analysis of Power Output and Efficiency of Magnetically-coupled Wireless Power Transfer System with Different Compensation Typology

Wireless power transmission (WPT) has become an increasingly popular and effective technique in transport electrification. Both the power transmission efficiency and the charging duration are two decisive factors in determining the performance of the WPT system, which are highly influenced by the circuit typology and parameters. Based on the magnetic resonant circuit theory, this paper discusses the principle of the four different equivalent typology circuits to achieve WPT, which are series-to-series (SS), series-to-parallel (SP), parallel-to-parallel (SP) and parallel-to-parallel (PP), from the aspects of input frequency, load value, and coil distance. Numerical simulation is conducted to validate the deduced equations. Circuit simulations of the four models are constructed in Matlab Simulink. The results reveal that under the same condition, the SS-WPT circuit can provide higher power with a lower percentage of power loss compared with other topologies, which can be a favorable option to design a WPT system.