Design And Analysis Of A Capacitive Vibration-To-Electrical Energy Converter With Built-In Voltage

This paper reports on the design and analysis of a capacitive vibration-to-electrical energy converter. A theoretical design model of a parallel-plate electrostatic spring-mass-system is presented, based on state space equations. The charging of the parallel-plate capacitor takes place by utilizing materials with different work functions for the electrodes. Numerical simulations are performed in order to optimize design parameters targeting a maximum output power. Such a micro-electro-mechanical system (MEMS) based capacitive energy converter is able to provide an output power of 4.28 muW at an external vibration with a frequency of 1 kHz and an amplitude of 1.96 m/s
²
(0.2 g). This corresponds to a power density of 79.26 muW/cm
³
based on a typical MEMS die size