A High-Performance Wireless Power Transfer System for Cardiac Pacemaker Based on Multi-MNG

In response to the issues of low transmission efficiency, poor offset tolerance, and severe magnetic leakage in wireless energy transmission systems for cardiac pacemakers, this article presents a novel wireless power transfer system for cardiac pacemakers based on multimagnetic negative materials (Multi-MNG). Based on the theory of equivalent medium for magnetic negative materials (MNGs) and the distribution of magnetic fields, three different metamaterial units with varying magnetic permeabilities are designed and arranged in a mixed manner to ensure effective convergence of the system’s magnetic field, shield magnetic field leakage, and reduce specific absorption rate (SAR). The accuracy, high efficiency, robustness, and safety of the Multi-MNG system’s transmission are validated through simulations at 8.94 MHz, and it mitigates the impact of magnetic leakage on the human body without a significant decrease in transmission performance. The maximum SAR value of the system is 0.0000504. The transmission performance of the Multi-MNG system is compared with that of ferrite, an unshielded MNG array 1 system, and a traditional system. The experiment unequivocally verifies the high performance of the Multi-MNG system, with a demonstrated maximum system output power of 1.323 W and a transmission efficiency peaking at 72.1%, The temperature rise is $2.9~^{\circ }$ C, which meets human safety standards.