Increase in High-Frequency Magnetic Fields due to Parallel Coils Added to Applicator for Hyperthermia Therapy

摘要

Induction heating type hyperthermia is important area of fusion research in engineering and medicine because of its use as a less invasive cancer therapy. The generation of high-frequency and high-level magnetic fields is a key research issue that will determine the practicality of the medical treatment. We previously proposed double pancake-type coils with wireless transmission. The system generated high-frequency magnetic fields with more than 200 kHz×mT on a human scale apparatus. To increase the amplitude of the magnetic field and to decrease losses in exciting coils, we proposed the use of parallel coils that have a special structure consisting of Litz wire. The parallel coils are designed to be connected by wireless transmission instead of a simple parallel connection. This paper discusses the equilibrium of currents on an applicator with wireless transmission that was obtained through simulations and experiments.