A design of mass-spring type piezoelectric energy harvesting

This study describes an experimental power generation system based on piezoelectric energy conversion for low power applications such as wireless sensor nodes. Piezoelectric transducers (PZTs) are especially suitable for energy harvesting from ambiance. A PZT is able to produce an open circuit voltage at hundreds volt level. But acquired current may be achieved at nano – micro scale. Therefore, PZT energy harvesters (PEH) have a very limited power generation capability. In order to generate higher output power, a series of PZT should be used in a PEH with proper electrical connection. In this paper, PEH is presented with a novel circuit topology for increase output power. The experimental system uses 20 diaphragm type PZTs with a 15 cm spring mounted at the center of each transducer. Necessary vibration is produced via a spring – mass structure of each PZT. Mass – spring structure is vibrated by the effect of wind. The maximum output power of the presented experimental generator for a nominal wind speed of 12 m/s is around 10.8 mJ. Results shows that proposed experimental generator is suitable for low power applications and output power of generator can be increased by using more PTZ is connected used circuit topology.