Design and Analysis of a Multi-Stage High-Power Converter for Wireless Electric Vehicle Charging toward Sustainable Transportation

This paper introduces the design and analysis of a multi-stage high-power converter-based wireless power transfer system for electric vehicle (EV) battery charging. The grid-to-battery architecture proposed consists of an AC rectifier, a DC link filter, a high-frequency inverter, an inductive power transfer link, a secondary rectifier, an output filter and a battery-monitoring unit. Unlike most of the previous works on the single-stage converter optimization and/or the design of compensation network, this work considers the entire circuit level power conversion path, such as the switching devices, resonant components, coupled coils, measurement points, and state-of-charge monitoring. Key electrical parameters for evaluation of the system performance are the DC-link voltage, inverter output voltage, transmitter-coil current, receiver induced voltage, rectified DC output, battery voltage, charging current and state of charge. Special focus is placed on converter-stage integration, DC-link voltage stability, resonance tuning, output filtering and stage-wise monitoring, which prevents unreliable and ineffective battery charging. The proposed architecture and design offer a complete basis for the future development of closed-loop control, the compensation of coil misalignment, bidirectional power transfer, and hardware implementation. In summary, this research helps to deepen understanding and improve optimization of multi-stage wireless EV charging system for sustainable transportation.