Design and Study of Vibration Energy Acquisition Equipment Based on Nonlinear Magnetic Coupling Action

In this paper, a vibration energy acquisition device based on nonlinear magnetic coupling action is proposed. The piezoelectric element is deformed under the nonlinear magnetic force of the magnets and can output electrical energy based on the positive piezoelectric effect. The array arrangement of rectangular and circular piezoelectric sheets is designed to achieve high output power. Non-contact magnetic excitation in the excitation mode was chosen to avoid mechanical collision and device wear and to improve the service life. The equivalent analysis of the piezoelectric element is carried out, and the control equation of a Lagrange curve is combined. The natural frequencies of the rectangular and circular piezoelectric elements under modal analysis are obtained by simulation analysis. Experiments show that when magnets 1 repel each other and magnets 1 and 2 attract each other, the output voltage of the prototype is 73.75 V. When the load resistance is 10 k Omega, the output power of the prototype is 256 mW. The experimental device collects the vibration energy from excitation and then stores the electrical energy in a storage circuit. After the electrical energy output by the device is rectified by the rectifier bridge, 72 light-emitting diodes (LEDs) can be lit, and power can be successfully supplied for the temperature and humidity sensor. The device worn on the wrist can harvest the vibration energy of the swinging arm, which confirms the good output performance of the device. The proposed device provides innovative ideas for the field of vibratory energy harvesting.