Analysis and Comparison of Compensation Networks for Multi-Megahertz Inductive Power Transfer

Increasing the operating frequency into the multimegahertz range significantly reduces coil size and cost in inductive power transfer systems, making it an attractive solution for electric vehicle charging. As a core component, the compensation network fundamentally influences overall performance. This paper provides a comprehensive analysis of the trade-offs among various compensation topologies and presents a series of design guidelines to achieve maximum power-transfer efficiency. Additionally, experimental results at 6.62MHz and 300W with 10 cm diameter coils at 2 cm separation demonstrate that all four topologies can achieve similar maximum efficiencies exceeding 96%. Although parallel-compensated capacitors may encounter higher thermal stress at elevated power levels, each topology can be optimized to meet specific load and power requirements.