Maximum Efficiency Point Tracking Scheme for Constant Output WPT System with Double-side LCC Compensation

This paper proposes a novel inductive coupled power transfer (ICPT) system, characteristic of double-side LCC compensation, switch-controlled capacitor and active rectifier. Constant current output can be realized when load changes or coupling coefficient fluctuates even in a relatively large range, which is suitable for electric vehicles (EVs) lithium battery charging. After analyzing the relationship between system efficiency and equivalent load resistance, impedance matching methods of both single-stage rectifier and two-stage interleaved rectifier are given. It is found that by reasonably adjusting the angle of MOSFETs in the rectifier, the magnetic coupling mechanism can realize approximate maximum efficiency point tracking (MEPT), thus improving the power utilization rate of EVs charging system.