A novel two-degree-of-freedom MEMS electromagnetic vibration energy harvester

Abstract

In this paper, a vibration-based MEMS electromagnetic energy harvester (EM-EH) device with two-degree-of-freedom (2DOF) configuration has been presented, modeled and characterized. The proposed 2DOF system comprises a primary subsystem for power generation, and an accessory subsystem for frequency tuning. A lumped parametric 2DOF model is built and examined in respect of energy harvesting capabilities. By controlling the mass ratio and frequency ratio, the first two resonances of primary mass can be tuned close to each other while maintaining comparable magnitudes. The 2DOF configuration is expected to be more adaptive and efficient than the conventional 1DOF structure, which could only operate near its sole resonance. The 2DOF EM-EH chip is fabricated on silicon-on-insulator (SOI) wafer through double-sided deep reactive-ion etching (DRIE). Induction coil is only patterned on the primary mass for energy conversion. With current prototype at an acceleration of 0.12 g, two resonances of 326 and 391 Hz with output voltages of 3.6 and 6.5 mV are obtained respectively, providing good validation for the modeling results. This paper offers new insights of implementing a multimodal MEMS EM-EH device.

Hybridizing linear and nonlinear couplings for constructing two‐degree‐of‐freedom electromagnetic energy harvesters

“…25,32,37,38 However, little attention has been paid to the 2-DOF cylindrical structures, particularly the cylindrical structures with nonlinear configurations. 25,32,37,38 However, little attention has been paid to the 2-DOF cylindrical structures, particularly the cylindrical structures with nonlinear configurations.…”

“…9 For the cantilevered EMEH, broadband energy harvesting can be implemented by using a cantilever array, 22 tuning the EMEH resonant frequency, 23 making use of multiple vibration modes, 24 increasing the degree of freedom (DOF) of EMEHs, 25 and introducing nonlinearity into the cantilevered EMEHs with the help of magnetic coupling or curved fixture. For the eccentric rotor-based EMEHs, torsional springs have been employed to provide additional support for the swing motion of the rotor to enhance the energy conversion efficiency.…”

“…7,26,27 Improving the power output of the cylindrical EMEH is usually accomplished by increasing the number of coils or moveable magnets, 28 whereas expanding the operating bandwidth is currently realized by arranging additional magnets around the tube to transform the mono-stable EMEH to a multistable EMEH. 25,32,33 However, it is still unclear if this improvement in the working bandwidth can be accomplished by converting the 1-DOF cylindrical EMEH to a 2-DOF cylindrical harvester that may contain nonlinear oscillators. As a result, low power output can be expected under low-frequency but large-amplitude excitations.…”

Energy Dissipation Contribution Modeling of Vibratory Behavior for Silicon Micromachined Gyroscope

“…Energy conversion is a fundamental characteristic of these vibrational system. For some type MEMS devices, vibration regarded as energy is collected as power of electrical components, such as vibration energy harvest [1][2][3]. For another type devices, this vibration behavior can be localized to improve signal noise ratio (SNR) greatly [4].…”

An Impact-Based Frequency Up-Converting Hybrid Vibration Energy Harvester for Low Frequency Application

“…Among them, the vibration energy is widely distributed, and possesses high energy density. Generally, the transduction mechanisms of vibration energy harvesting can be divided into piezoelectric [1], electromagnetic [2], electrostatic [3], and magnetoelectric [4]. Due to the high electromechanical coupling coefficients, simple processing, and no external power supply, piezoelectric energy harvesting is the one of the most reported transduction mechanism.…”