2018 年 42 巻 2 号 p. 49-54
Implantable medical devices are utilized in the human body for maintaining good health. As these devices are becoming increasingly functionalized, supplying power to them has become very important. Instead of batteries, technologies for wireless power supplies are being developed, such as inductive coupling or piezoelectric elements. However, we propose the use of magnetic wires for this purpose. Inside these wires, a fast magnetization reversal, called a “large Barkhausen jump,” occurs due to an applied magnetic field. This reversal induces a large pulse voltage in pick-up coils, which is called a “Wiegand pulse.” By applying this pulse as an electric source, a higher electric power is expected compared with the conventional method using a sinusoidal excitation field. A wire core coil was prepared, and open-circuit voltage was measured. In addition, DC voltage and electric power were measured by connecting the wire core coil to a rectifier. The experimental results confirmed the superiority of using a Wiegand pulse at an applied magnetic field intensity of 60 Oe and a frequency of lower than 10 kHz.
