Design of a Multi-Spiral Solenoidal Inductor for Inductive Power Transfer in Biomedical Applications

Inductive power transfer is the most common method for transferring power to implantable sensors inside human body. For good inductive coupling, the inductors should have high inductance and high quality factor. But the physical dimension of the receiver inductor cannot be large due to biomedical constraints. Therefore, there is a need for small size and high inductance, high quality factor inductors for implantable sensor applications. In this work, design of a multi-spiral solenoidal inductor for biomedical application is presented. The inductors are simulated and optimized for targeted application using a commercial electromagnetic tool, Sonnet. Parametric study of the multi-spiral inductor is investigated in terms of number of layers, metal spacing, and metal width. Finally, it is demonstrated that the proposed multi-spiral solenoidal inductor exhibits a better overall performance in comparison with the conventional spiral inductors for biomedical applications.