Efficiency and power sizing of SS vs. SP topology for wireless battery chargers

The paper deals with the wireless battery chargers (WBCs) of electric vehicles (EVs) and refers to a resonant WBC that utilizes a rectifier-chopper stage in the receiver side to control the charging current/voltage of the EV battery. Two topologies, namely series-series and series-parallel, are considered, and their performance in terms of efficiency and power sizing is investigated. Power sizing is formulated for both the power source and the coil coupling set. Instrumental in the investigation is the proper modeling of the rectifier-chopper stage. Data used for calculating the performance are obtained from a WBC setup for electric city-car. Comparison of the results reveal the overall convenience of the series-series topology.