Experimental And Numerical Evaluation Of Stacked Piezoelectrics For Mechanical Energy Harvesting

Fundamental understandings on electromechanical responses of stack piezoelectric transducers are addressed in this work. A systematic comparison and evaluation is carried out by designing, simulating, fabricating and testing a family of mechanically serial and electrically parallel stacked piezoelectric transducers. The objective of this research is to design reliable and optimized mechanical to electrical energy conversion modules for self-sustained sensing and communication. Utilizing finite element analysis (FEA) COMSOL tools, energy conversion dependence on frequency, number of layered stacks, geometrical factors, load matching, etc. is explored. Simulations for mechanical stress at low frequency mechanical vibration conditions indicate that while energy stored continues to increase as the number of the stacks increases, energy volume density and the power conversion efficiency can be optimized. The simulation results are applied in fabricating energy conversion modules to achieve high conversion efficiency while minimizing the size and cost of the materials, which are tailored to match the given mechanical energy source and operation conditions.