Transcutaneous Energy Transfer System for Cardiac-Assist Devices by Use of Inhomogeneous Biocompatible Core Material

Abstract

A novel magnetic liquid silicone rubber composite core design applicable to wireless power transfer (WPT) for medical applications is presented. As a case study, the integration of WPT, including the proposed cores for the coils, with ventricular assist devices (VADs) was investigated. This facilitates transferring 4.6 W of power wirelessly through the skin-layer, which thus allows to dispose of the transcutaneous cable that connects the extracorporal batteries to the implanted blood pump. To enhance the coupling coefficient and consequently increase the WPT efficiency, the geometry of the cores was optimized. This reduces the temperature increase in implant area. The field and thermal simulations were carried out with CST software. The electrical properties of the proposed design as obtained by simulation were validated by measurements. The simulation results perfectly coincide with the measured results. Finally, a new optimized design with additional high permeability core inserts is introduced to further increase the coupling coefficient. The results indicate that the coupling coefficient is increased from 0.31 to 0.52 with the optimized design, in comparison to the case without cores. Moreover, by fixing the initial temperature as 37 • C, the maximum temperature is decreased from 38.19 • C to 37.27 • C, while keeping the transferred power fixed. Its high magnetic conductivity, biocompatibility, low-loss property, flexibility and Qi-standard compatibility make the proposed WPT design an excellent candidate for the wireless-powering of heart assist devices such as VADs.

Wireless charging for cardiac pacemakers based on class‐D power amplifier and a series–parallel spider‐web coil

“…Equations were derived for optimal solenoid design parameters according to the input current and the size of the transmitted coil. The mathematical model has been practically verified by Khalili et al, 36 who developed a flexible, biocompatible, and highly magnetically conductive WPT system for used in ventricular assist devices (VADs). Their system design is based on a novel inhomogeneous material for the core.…”

Wireless Power Transfer Systems With Composite Cores for Magnetic Field Shielding With Electric Vehicles

“…However, although a high-permeability magnetic core can reduce magnetic reluctance and orient the magnetic field, the magnetic loss is high [43]. This study used flexible magnetic material cores comprising an insert block with low loss and high permeability (≈ 230) [44], [45], where the flexibility improves system robustness against mechanical stress and vibration [46]. The cores are made of liquid silicon rubber with a magnetic filler in form of a powder and cut by laser to fixes custom request designs in the realistic manufacture [47].…”

“…Moreover, Table 2 lists their electromagnetic parameters. The relative permittivity, relative permeability, and electrical conductivity with respect to the core along with the insert material were measured at the LVSP Institute of Polymer Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) [44], [45]. In [41], the detailed production process of the core material is explained.…”

New Era of Electroceuticals: Clinically Driven Smart Implantable Electronic Devices Moving towards Precision Therapy

“…Maybe more optimization studies with the help of simulation tools that could provide field distributions analysis help us increase the inductor's capacity further. Introducing magnetic core material reduces the temperature increase in the implant area [61]. High permeability materials for the core, even more, the laminated core structures could be potential candidates to overcome the traditional issues and limitations.…”

“…High permeability materials for the core, even more, the laminated core structures could be potential candidates to overcome the traditional issues and limitations. Moreover, high magnetic conductivity, biocompatibility, low loss property, and flexibility allow us the usage of these materials to develop efficient wireless power transmission systems for heart assist devices such as ventricular assist devices, etc., [61].…”