Research on Composite Shielding of Sector‐Shaped Coil for Resonant Wireless Power Supply Cardiac Pacemaker

ABSTRACT In response to the issues of severe magnetic leakage in the wireless power transfer (WPT) system for cardiac pacemaker, which poses a threat to human safety, this paper proposes a composite shielding method for a resonant wireless power supply cardiac pacemaker sector‐shaped coil operating at a frequency of 180 kHz. Firstly, the working principle of the sector‐shaped shielding coil is analyzed, and a WPT system based on the LCC‐S compensation circuit is constructed. The structural parameters of the system are determined by optimizing the coupling coefficient between the transmission coils. Secondly, in order to investigate the influence of the central angle on the shielding performance of the circumferential sector‐shaped shielding coil, five different shielding schemes are designed and their magnetic field leakage confinement capabilities as well as system performance are studied. Considering the potential risks of leakage magnetic fields to human health, a human model is established in COMSOL for safety assessment. Finally, an experimental platform is designed and constructed. The experimental results show that, after incorporating the 120° circumferential sector‐shaped shielding coil and composite shielding material, the leakage magnetic field at a distance of 36 mm from the center decreases by 34.7%, and the transmission efficiency is 72.3%. Under a 30‐min charging test, the maximum tissue temperature rise is only 1.2°C, which complies with human safety standards.