Study and design of a resonant inductive coupling based magnetic stimulator

• Main Author: Ma, Qiang
• Other Authors: School of Electrical and Electronic Engineering
• Format: Theses and Dissertations
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/54885
• Institution: Nanyang Technological University

With the growing trend of using stimulation therapy to relieve diseases or ease pain, various methods or technologies has been created and put into clinical use. Among these stimulation modalities which are capable for non-invasive or minimally invasive treatment, magnetic stimulation has been proved to be both an effective and promising treating method by using time varying magnetic flux to drive currents and generate electric field in the human body tissue. To design a magnetic stimulator of high efficiency, nerve and pain mechanism is fully understood and analyzed. Mathematical modelling of the stimulation mechanism has been performed to lay the proper foundation for circuit design. An entire circuit topology is developed the circuits for performing magnetic stimulation. Theory of resonant inductive coupling is illustrated and verified by usmg software and hardware simulation. Parameters which result in highest transfer efficiency has been studied which forms a basis for the specified design of stimulating circuit. A magnetic stimulator consisting of primary and secondary coils, resonant capacitors and ferrite core is designed based on the principle of resonant inductive coupling as well as the idea of using flux concentrators to generate high electric field in the fat tissue. Software simulations have been performed and improvement of 63.48% and 117.13 % in maximum electric field at 450 KHz has been achieved with respect to resonant structure without ferrite core and non-resonant structure which is desirable for the purpose of nerve stimulation.