Abstract:
Microelectromechanical system of electrostatic energy harvesters is modeled
using a nonlinear state–space approach in this research. The analytical models of
in-plane overlap, in-plane gap closing, and their compound structures are used to
analyze the energy harvesting performance from heartbeats-generated vibrations.
The detailed models of both electrical and mechanical subsystems including
stopper function, motion drag, parasitic capacitors, and energy converter
capacitors are developed in the format of state–space equations. To reach the
optimal heartbeat energy harvesting, typical 1D harvesters are developed and
allowed to move in x–y and x–y–z directions. Accordingly, the optimal harvester
combines the features of in-plane overlap and in-plane gap closing energy
conversions, and so allows efficient absorption of energy released by heartbeat in
different directions. This 3D feature gives a considerable rise to power generation
to 35.038 μw at the same size compared to the new rate of the in-plane overlap or
in-plane gap-closing electrostatic harvesters individually.
