A Spider-Web Design for Decreasing Eigen-Frequency With Increasing Amplitude in a PE/ME Composite Energy Convertor

Aiming at improving the energy collection efficiency for low-frequency vibrations, a new spider-web shaped plate (SWSP) is designed to achieve the target of increasing the amplitude with decreasing the eigen-frequency (abbreviated as IADEF) in a piezoelectric/magnetoelectric composite convertor integrating with a magnet. Through analytically optimizing the proposed SWSP, the increasing of output voltage with the decreasing of eigen-frequency can be accomplished effectively at both micro- and mesolevels. The above expected IADEF effect is experimentally observed and further verified with fabricated SWSP prototypes. Compared to a conventional one, the optimized SWSP decreases the eigen-frequency by a large percentage and remarkably increases the output voltage. An optimal positioning of the magnet is found to be conducive to the maximization of the output voltage, while the geometrical contribution of the magnet design to IADEF is also observed. This work is of great significance for the design of high-performance low-frequency energy convertor as well as the development of self-powered devices and battery-free electromechanical systems.