Achieving Electromagnetic Compatibility of WPT Antennas for Medical Imaging in MRI

Abstract

The compatibility of TX and RX antennas commonly used for WPT is analyzed for use in Magnetic Resonance Imaging (MRI) systems. The analysis revealed that commercially available antennas are not compatible with MRI systems and pose a safety risk to patients. This paper presents a protection circuit that protects the antennas and prevents them from interacting with the MR System. The effectiveness of the circuit is proven through experiments in the MRI system and on the bench. The paper discusses a circuit that can render the WPT coils invisible to the MRI system. The WPT power transfer remained unaffected with this filter circuit. With and without the filter, a maximum power of 22 W was measured at the load with a transfer efficiency of 62%.