Investigation of a Nonlinear Energy Harvester

A Nonlinear Energy Harvesting with Asymmetry Compensation

“…It consists of a beam of flexible PET (PolyEthylene Terephthalate) of dimensions 6 cm by 1 cm, with thickness 140 µm, in a STB configuration obtained by a pre-compression ΔY = 1 mm along the y axis, a proof mass placed in the middle of the beam and two piezoelectric transducers Midè Volture V21BL placed at the two stable positions [9]. A real view of the harvester is shown in Figure 1b.…”

“…A proof mass of 4.77 g composed by two identical disk shaped permanent magnets S-10-04-N [11] with diameter 10 mm and height 4 mm has been used to optimize the trade-off between the range of frequencies in which the beam can follow the input signal dynamics and the minimum force that allows the switching [7,9].…”

“…The advantages of this system, over traditional linear harvesters stem, mainly, from the intrinsic nonlinear nature of the conversion process which allows for rapid switching (between the two stable states) and large displacements, both of which are crucial to enhancing the efficiency of the power conversion process. In [9,10] a harvester exploiting the STB configuration has been demonstrated, experimentally, to be capable of scavenging energy from both deterministic and random vibration sources in the range 0-15 Hz; it generates power up to 160 µW with an average conversion efficiency of about 15% in case of horizontal operation. Moreover, a nonlinear dynamic model fitting the behavior of the STB device has been presented.…”

Investigation of a Nonlinear Vibrational Energy Harvester in the Stochastic Resonance Regime

“…As a main drawback the STB configuration requires a minimum acceleration to activate the beam switching between its two stable states. Such threshold acceleration depends on the system characteristics (beam length, pre-compression, proof mass) [3,5].…”

“…Solutions exploiting a STB beam configuration have been recently presented by the authors [3,[5][6][7][8] and demonstrated to be capable of power a wireless transmitter [9]. In [10,11] a magnetic repulsion mechanism to compensate for the asymmetric behavior of the device, in the vertical direction, due to the effect of the proof mass load, has been presented.…”