53 / 2021-03-28 19:45:04

Nonlinear broadband energy harvesting characteristics of Lambda-shaped piezoelectric energy harvesters using a pair of magnets

Nonlinear broadband,Lambda-shaped,piezoelectric energy harvester,magnets,analytical model

Self-powered systems such as medical devices, wearable devices, and wireless sensors that exploit piezoelectric energy harvesters (PEHs) have gained a lot of attention recently as the Internet of Things (IoT) technology has been introduced. As an alternative energy solution to battery, PEHs supply stable power to the devices by harvesting ambient vibration energy. The principal objective of this research is to show the superior and robust characteristics of Lambda-shaped PEHs using a pair of magnets. The equations of motion of the proposed harvester were derived by employing the Kane’s method and Euler–Bernoulli beam theory. The accuracy of the analytical model was validated with finite-element analysis and experimental results. Using the analytical model, the optimal load resistance and corresponding maximal output power of the proposed harvester were determined. Under the same base excitation condition, the Lambda-shaped PEH generates more power than the conventional cantilever shape PEH. The effects of base excitation direction and shape angle of the Lambda-shaped harvester on the energy harvesting performance were investigated with the analytical model. Moreover, the broadband energy harvesting characteristics of the proposed Lambda-shaped PEH could be also investigated with the analytical model.