Proposal of Compact Active and Reactive Power Processing Circuit for RI-WPT Receivers

Abstract

Wireless Power Transfer (WPT) concept has been realized through many technological methods to feed power in a cordless way in many applications. Among these various methods, Resonant Inductive Wireless Power Transfer RI-WPT has been extensively used to charge the batteries for consumer electronics such as smartwatches, mobile phones, and laptops. However, at high resonant frequency, this technology is vulnerable to the frequency variation in transmitter and receiver circuits, which results from components tolerance and other related factors. Frequency mismatch severely drops the conversion power efficiency and deteriorates the effectiveness of RI-WPT. To solve this issue, this paper proposes and verifies a novel active and reactive power control circuit at the receiver side of a wireless power transfer system. A 10W 127.7 kHz RIWPT receiver system is designed and verified against variations in compensation network elements, where 1. 3W is recovered after frequency re-tuning thanks to the proposed circuit.