This paper presents an advanced study including the design, characterization and theoretical analysis of a capacitive vibration energy harvester. Although based on a resonant electromechanical device, it is intended for operation in a wide frequency band due to the combination of stop-end effects and a strong biasing electrical field. The electrostatic transducer has an interdigited comb geometry with in-plane motion, and is obtained through a simple batch process using two masks. A continuous conditioning circuit is used for the characterization of the transducer. A nonlinear model of the coupled system ‘transduce-conditioning circuit’ is presented and analyzed employing two different semi-analytical techniques together with precise numerical modelling. Experimental results are in good agreement with results obtained from numerical modelling. With the 1 g amplitude of harmonic external acceleration at atmospheric pressure, the system transducer-conditioning circuit has a half-power bandwidth of more than 30% and converts more than 2 µW of the power of input mechanical vibrations over the range of 140 and 160 Hz. The harvester has also been characterized under stochastic noise-like input vibrations.

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This paper reports a batchfabricated, lowfrequency and wideband MEMS electrostatic vibration energy harvester (eVEH), which implements coronacharged vertical electrets and nonlinear elastic stoppers. A numeric model is used to perform parametric study, where we observe a wideband bimodality resulting from nonlinearity. The nonlinear stoppers improve the bandwidth and induce a frequencyup feature at low frequencies. When the eVEH works with a bias of 45 V, the power reaches a maximum value of 6.6 μW at 428 Hz and 2.0 g rms , and is above 1 μW at 50 Hz. When the frequency drops below 60 Hz, a 'frequencyup' conversion behavior is observed with peaks of power at 34 Hz and 52 Hz. The −3 dB bandwidth is more than 60% of its central frequency, both including and excluding the hysteresis introduced by the nonlinear stoppers. We also perform experiments with wideband Gaussian noise. The device is eventually tested with an RF data transmission setup, where a communication node with an internal temperature sensor is powered. Every 2 min, a data transmission at 868 MHz is performed by the sensor node supplied by the eVEH, and received at a distance of up to 15 m.