ENERGY STORAGE CAPACITY OF VIBRATING STRUCTURE : APPLICATION TO A SHOCK SYSTEM

In this paper we present first results on the capacity of vibrating structures to store mechanical energy and then convert it in electrical energy through the piezoelectric effect. The main applications concern vibration energy scavenging for micro power generators. The mechanical energy is transmitted to the vibrating structure by a shock event on the package. We have compared two basic structures. The first one is a PZT piezoelectric plate stuck to the package and the second one is a three layers structure composed of a PZT plate, a silicon beam and a PZT plate stuck to the same package. We have clearly experimentally pointed out the contribution of the silicon beam for harvesting mechanical energy.