Self-Driven Current-Doubler Synchronous Rectifier and Design Tuning for Maximizing Efficiency in IPT Systems

• Published in: IEEE journal of emerging and selected topics in power electronics Vol. 10; no. 1; pp. 1007 - 1016
• Main Authors: Scortegagna, Renato Gregolon, Gules, Roger
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 01-02-2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Analog circuits; Capacitance; Circuit design; Circuits; Coils (windings); Conduction losses; Configurations; Couplings; DC–DC power conversion; Diode rectifiers; Driver circuits; Efficiency; Gates (circuits); inductive power transfer (IPT); Inductors; Load fluctuation; Logic gates; Misalignment; Power transfer; resonant power conversion; RLC circuits; self-driven rectifier; Switches; switching circuits; synchronous rectifier (SR); Tolerances; Windings
• ISSN: 2168-6777; 2168-6785
• DOI: 10.1109/JESTPE.2021.3105041

A novel driving circuit for a current-doubler synchronous rectifier (SR) to inductive power transfer (IPT) applications is proposed in this article using only auxiliary windings in the existent rectifier output filter inductors to drive active switches. The proposed SR overcomes the limitations of the traditional driving schemes because it does not require any processing, analog circuits, gate driver circuits, or current measurement, normally used in the conventional SR applied to IPT systems. The proposed configuration presents a simple and robust operation considering usual parametric variation in IPT systems, such as coupling factor, misalignment, load variation, and component tolerances. Moreover, the same size and weight of the conventional diode rectifier board are maintained due to the simplicity of the self-driven circuit. The proposed configuration allows increasing the global efficiency by reducing the conduction losses of the output rectifier and previous stages. A resonant circuit design procedure using an iterative process to find the maximum efficiency point considering the self-driven SR is proposed to maximize the global system efficiency. A 100-W resonant series-parallel IPT prototype is developed to validate the performance of the proposed self-driven SR circuit presenting a maximum global efficiency equal to 94.8%.