Modeling for Piezoelectric Stacks in Series and Parallel

Piezoelectric energy harvesting is a new type technology of green energy. To increase energy harvesting efficiency from below frequencies, which exist mostly in ambient, the piezoelectric stack assembled electrically in series and parallel is used as the energy harvester. Based on the third piezoelectric equations and equivalent circuit, the output voltage and power equations of piezoelectric stacks in series and parallel in d33 mode are derived. Higher voltage can be obtained from serial piezoelectric stack while higher power can be generated from parallel one. The results are verified by the experiment conducted on PZT-8. It is shown that the theoretical and measured values fit very well.