2020 Volume 28 Issue 2 Pages 156-162
The functions of sensing, control and communication in wireless sensor devices could be driven with minute electric power below mW level. In these devices, attention has been paid to minute electric power supply from environmental energy (light, heat, vibration, electromagnetic fields, etc.) instead of batteries. The power induced by leakage magnetic fields is a stable minute sources secured near electric power equipment. We proposed an environmental magnetic-field generator consisting of a solenoid coil and an prolate shell-type magnetic core to compress low-level magnetic fields below mT. The analytical equation of the electromotive force induced on the generator could be derived to characterize the performance. The validity of the equation was discussed by comparing the experimental results of the tested models with the calculated values by the expression. It was clarified that the shape of the generator was discussed and that a small power of mW level could be supplied.
