A Hybrid Compensation Topology With Single Switch for Battery Charging of Inductive Power Transfer Systems

This paper presents an inductive-power transfer (IPT) system with load-independent constant current (CC) and constant voltage (CV) charging characteristics for low power systems. An inductor-capacitor-capacitor series (LCC-S) compensation-based hybrid topology that can achieve both CC and CV charging with only one additional switch under zero-phase-angle conditions is proposed. Additionally, the CC/CV charging mode can be realized with two different fixed frequencies. The proposed system has a simple structure and low cost and uses only primary-side electrical information to control the battery charging profile, achieving communication-less control between the primary and secondary sides. It greatly simplifies the controller design process. A 200-W laboratory prototype is built to verify the feasibility of the proposed topology, and the maximum efficiencies of the CC and CV modes are approximately 85% and 87%, respectively.