Design of high-performance receiver coil for transcutaneously magnetically coupled resonance wireless power transfer

Aiming at the problem of low quality factor，high self-resonant frequency of the small receiver coils inside the body，and the difficulty in matching the resonance with the external coils in transcutaneously wireless power transfer for implanted devices，the use of multiple sub-coils connected in series to construct the receiver coil that also served as the case of the implanted circuit was proposed，and the printed planar spiral coil (P-PSC) with an outer diameter of 26 mm in the sub-coils was optimized for design．On the basis of determining the substrate material，substrate thickness and track thickness，the partial element equivalent circuit (PEEC) method was used to simulate and calculate the self resonant frequency and quality factor of P-PSC．The influence of inner radius，number of turns，and the ratio of trace width to spacing was analyzed，and the design parameters of low-profile and high-performance P-PSC were optimized．The proposed double-layer P-PSC prototype was fabricated with the measured self-resonant frequency of 10.37 MHz and quality factor of 82.3． Results show that the proposed single and double-layer P-PSCs are superior to those documented comparable coils．A hollow receiver prototype with 26.00 mm in outer diameter and 4.55 mm in height is constructed with the self-resonant frequency of 6.78 MHz and the quality factor of 67.1．Under the condition of meeting safety restrictions，the received power at a distance of 4 cm from the transmitter is 269 mW with the power transfer efficiency (PTE) of 24.2%. © 2024 Huazhong University of Science and Technology. All rights reserved.