植入式医疗设备经皮能量充电系统设计与实验

Design and experiment on transcutaneous energy charging system in implantable medical device

基于电磁耦合原理设计了一套应用于植入式医疗设备经皮能量充电系统,解决了因拖缆供电或更换电池而多次手术的不便和隐患。建立了传输链路等效模型,分析了线圈品质因数和接收端等效负载对系统传输效率和接收电压的影响,优化线圈设计,设计了隔离式电池管理充电电路。实验结果表明,新式14股双层Litz线串联线圈性能满足实际应用要求,在有效充电距离10～38 mm内,最大接收功率和传输效率分别为2 400 mW(23 mm,54%)和81%(11 mm,870 mW)。此外,针对不同的充电过程中等效负载电阻的变化,系统无需复杂的控制电路,依靠自身的阻抗特性响应即可保证体内接收电压均在安全范围内变化。

To solve the postoperative complication and infection problems caused by the methods of power delivery using percutaneous leads or battery, a new transcutaneous energy charging system based on inductive coupling is designed for transmitting electrical power to implantable device in this study. The equivalent model of the inductive link is estab- lished. The influence of coil quality factor and receiving end equivalent resistance on system transmission efficiency and receiving voltage is analyzed ;the coil design is optimized, the isolated battery management charging circuit is designed. Simulations and experiments were carried out to verify the performance of the proposed system. The results show that the performance of the serial double-layer coil with 14 Litz wires meets the requirement of actual application. The maxi- mum receiving power and transfer efficiency are 2 400 mW （23 mm,54% ） and 81% （11 ram,870 mW） ,respectively within the effective charging range of l0-38 mm. Furthermore,requiring no complex external control circuit and only relying on the natural impedance response, the system can guarantee that the receiving voltage is within the safety range and achieve the desired power-delivery profile across a wide range of load resistances during the charging period