Topology Selection and Parametric Design of Electromagnetic Vibration Energy Harvesters by Combining FEA-in-the-Loop and Analytical Approaches

Abstract

Electromagnetic energy harvesters have been used to capture low-frequency vibration energy of large machines such as diesel generators. The structure of an electromagnetic energy harvester is either planar or tubular. Past research efforts focus on optimally designing each structure separately. An objective comparison between the two structures is necessary in order to decide which structure is advantageous. When comparing the structures, the design variations such as magnetization patterns and the use of yokes must also be considered. In this study, extensive comparisons are made covering all possible topologies of an electromagnetic energy harvester. A bench mark harvester is defined and the parameters that produce maximum output power are identified for each topology. It is found that the tubular harvesters generally produce larger output power than the planar counterparts. The largest output power is generated by the tubular harvester with a Halbach magnetization pattern (94.7 mW). The second best is the tubular harvester with axial magnetization pattern (79.1 mW) when moving yokes are inserted between permanent magnets for flux concentration. When cost is of primary concern, the tubular harvester with axial pattern may become a best option.

Kinetic Vibration Energy Harvester Based on Electromechanical Converter with Power Electronics Active Rectifier

“…The vibrations of the system, excited by an external force, cause the movement of the magnet in the cylinder, and the change in the magnetic flux. This in turn induces a voltage in the winding, whose amplitude depends on the number of turns and the rate of change of the magnetic flux [12].…”

Design and analysis of motion and energy regulating vibration harvester

“…Halim et al 3 performed FEA to estimate magnetic flux density and electric power generated by a miniaturized rotary electric generator used for low frequency vibration energy harvester. Yoo et al 4 designed low frequency vibration harvester to deliver peak power of 51.4 mW and voltage of 3.8 V with use of planar and tubular magnet topologies. Electromagnetic generators have been used in human motion powered devices in case of wearable systems, which can be used to operate sensors for medical applications.…”