Design and Analysis of Piezoelectric Cantilever Based Vibration Energy Harvester for Low Power Devices

The advancement in technology lead to many low power electronic devices which may be powered autonomously by ambient sources like vibrations which are abundantly available in our surroundings. In this paper, the analysis and implementation of the method in which the low frequency ambient vibrations are used to generate low power using cantilever based piezoelectric vibration sensor is carried out. Here, the simulation of the sensor structure is done using COMSOL Multiphysics to analyze the stress, strain, displacement, natural frequency and modal frequencies of the designed cantilever. The effect of dimension of the structure (like length, width and thickness), the piezoelectric material, and the volume of the tip mass and clamp positions on natural frequency and voltage is analyzed. The optimized simulated values are compared with the theoretical values and the actual sensor’s (PPA 1001) values. The results are in close approximation. The output signal is rectified and conditioned so that it can be used to power electronic gadgets. LTC 3588 is used for signal conditioning. In this work, a massager having frequency range in 70-80Hz is used as vibration source. With the optimized values of sensor position, clamping and tip mass, the output voltage available is 16V (p-p). This is conditioned further to get a constant output voltage of 3.3 V.