Towards Real-Time and Energy-Efficient Inductive Wireless Power Transfer

Abstract

Wireless Power Transfer (WPT) is a key enabler for implantable and ingestible medical devices that require continuous, safe energy delivery without invasive wiring. We present a multiple transmitters inductive WPT platform implementing imec's Intelligent Magnetic Field Steering (H-Steering) concept to achieve real-time and energy-efficient receiver motion adaptation. Operating at 13.56 MHz, the system alternates between brief coupling factor estimation and longer power-delivery windows, applying feedforward current amplitude control and phase alignment via Delay-Locked Loop (DLL) across multiple transmitters. A robotic-arm-based framework emulates realistic motion up to 2 cm/s. Experiments confirm robust sub-milliwatt delivery across various velocities, demonstrating the feasibility of real-time and energy-efficient inductive WPT for dynamic biomedical applications.