Design and test of a Bennet's doubler device with mechanical switches for vibrational energy harvesting

[摘要] In this work, we demonstrate that the use of self-synchronized mechanical switches in replacement of diodes into electrostatic vibration energy harvesters (e-VEH) can lead to better power generation. Indeed, mechanical switches have the advantage of no leakage current and no threshold voltage. As a proof of concept, we use the Bennet's doubler electrostatic generator. The proposed e-VEH is composed of two variable capacitors triggered by a central electrode taken as an inertial mass. Ambient vibrations induce inertial forces on the central electrode, as a result a voltage doubling is obtained at each operating cycle. The mechanical switches are directly fixed to the moving electrode. In addition, no dedicated pre-charge is required: the system starts with ambient electrical charges. The device is fabricated and tested under harmonic motion. A comparison between the proposed design and those using diodes under the same operating conditions shows an experimental direct increase of the harvested electrical power of around 28%.

[发布机构] Applied Mechanics and Systems Research Laboratory, Tunisia Polytechnic School, University of Carthage, BP 743, La Marsa; 2078, Tunisia^1;Université Paris-Est, ESYCOM, ESIEE Paris, Noisy-le-Grand, France^2

[效力级别] 能源学

[关键词] Ambient vibrations;Electrical charges;Mechanical switch;Moving electrodes;Operating condition;Variable capacitor;Vibration energy harvesters;Vibrational energy harvesting