https://doi.org/10.1140/epjst/e2015-02585-5
Regular Article
Mechanical and electrical impedance matching in a piezoelectric beam for Energy Harvesting
1 Bialystok University of Technology, Faculty of Mechanical Engineering, Department of Automatics Control and Robotics, Wiejska Street 45C, 15-351 Bialystok, Poland
2 Bialystok University of Technology, Wiejska Street 45D, 15-351 Bialystok, Poland
3 Bialystok University of Technology, Faculty of Electrical Engineering, Department of Theoretical Electrotechnics and Metrology, Wiejska Street 45D, 15-351 Bialystok, Poland
a e-mail: a.koszewnik@pb.edu.pl
b e-mail: p.grzes@htech.com.pl
c e-mail: w.walendziuk@pb.edu.pl
Received: 30 August 2015
Revised: 9 September 2015
Published online: 20 November 2015
A piezoelectric beam is one of transducers for energy harvesting. It provides easy implementation and good performance in changing mechanical stress into electric voltage. In order to maximize output power, it is important to provide mechanical and electrical impedance matching. In the paper the authors proposed a methodology which allows to find values of lumped elements in an electromechanical model after completing appropriate measurements. Due to linear equations, it is possible to model a beam in both mechanical and electrical ways, and match the best load depending of frequency. The proposed model of a piezoelectric cantilever shows a potential use of these devices in micro scale as a cantilever which is a part of a silicon structure. Moreover, in the paper, the authors discuss mechanical aspects of using a weight as the way to tune the piezoelectric beam to a specific frequency. The electrical aspect of matching the source impedance with load, which is based on an electrical model of a piezoelectric transducer, is also presented. In the paper a mathematical model was verified by an experiment in which a laboratory stand equipped with a vibration generator, a piezoelectric energy harvester and acceleration sensors was used.
© EDP Sciences, Springer-Verlag, 2015
