This paper presents the simulation, fabrication, and experimental results of a vibration-based electromagnetic power (EMPG) generator. A novel, low cost, one mask technique is used to fabricate the planar coils and the planar spring. This fabrication technique can provide an alternative for processes such as Lithographie Galvanoformung Abformung (LIGA) or SU-8 molding and MEMS electroplating. Commercially available copper foils of 20 μm and 350 μm thicknesses are used for the planar coils and planar spring, respectively. The design with planar coils on either side of the magnets provides enhanced power generation for the same footprint of the device. The device overall size is 1 cm3. Simulations of the modal analysis of the spring-mass system and the magnetostatic analysis of the magnetic field generated by the magnets are performed with COMSOL multiphysics®. Excitation of the EMPG at the fundamental frequency of 371 Hz and at 13.5 g base acceleration (base amplitude 24.4 μm) yields an open circuit voltage of 60.1 mV, as well as 46.3 mV load voltage and 10.7 μW power for a 100 Ω load resistance. At matching impedance of 7.5 Ω the device produced a maximum power of 23.56 μW and a power density of 23.56 μW/cm3.

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