Coupling-Insensitive Inductive Power Transfer System Driven by Single-Switch Inverter

This article is devoted to improving the coupling insensitivity of inductive power transfer (IPT) systems. Unlike previous studies that focused on establishing a stable source on the primary side (e.g., through a full-bridge inverter), this article leverages the load-sensitive characteristics of a single-switch resonant inverter to achieve a more stable system under varying coupling conditions. In addition, instead of designing the inverter and compensated coupler in a decoupled manner, the whole system is viewed as an ultrahigh-order resonant converter. Through simplification, the existing analytical inverter model is modified to fully explore the design potential for coupling-independent zero voltage switching and high robustness under parameter variations. The modified model also fills the gap in the holistic modeling of single switch IPT systems. In the experiment, a 60 W prototype is designed, when the coupling coefficient varies from 0.085 to 0.17, the output power maintains a fluctuation of 12%, with peak efficiency reaching 89.12%.