Study of the efficiency of electrical generator using ferromagnetic powders by electromagnetic analysis

Abstract

Batteries or electric wires are currently in wide use for sensor energy supply. However, industrial waste caused by battery disposal are recognized as a social issue. In addition, the weight of the electric wires supplying electric energy to sensors can reach several kilograms in a car or several hundred kilograms in a passenger aircraft. Thus, reduction of electric wire weight can bring weight saving for a car or a plane. We performed a basic study of development of generation system using ferromagnetic powders and fluid. Such an electrical generator is inexpensive, uses kinetic energy naturally available in the living environment such as wave force, vibration, or shock, is maintenance-free and safe. Magnetic field of a permanent magnet is used in the electrical generator using ferromagnetic powders, that significantly contributes to generation. Electromagnetic fluid simulation and liquid metal magnetohydrodynamic power generation considering dynamic behavior of magnetic particles in magnetic field was studied before. However, electromagnetic analysis for magnetic particle in magnetic field for energy harvesting purposes is not studied. Therefore, in this work, we performed electromagnetic analysis using a general-purpose finite element simulation program and studied the efficiency of the electrical generator using ferromagnetic powders. We were able to assess generation efficiency by analyzing the magnetic flux distribution of the permanent magnet used for electricity generation.