Virtual instrument to obtain an optimal linear model for piezoelectric elements involved in road traffic energy harvesting

A new Virtual Instrument (VI) system is presented in this paper. The VI is designed to obtain the linear electrical models of the piezoelectric elements involved in energy harvesting applications in road traffic environments. The system, the modelling and the verification methodology are described in this paper, comparing the obtained results. The piezoelectric devices under test (PDUT) are mechanically driven by a test bench, which simulates the effect of heavy or light vehicles passing over a lane in a real road. Parameters such as the traffic flow rate and vehicle speed are configurable. In addition, the VI system controls the specific hardware designed to store the energy with different harvesting topologies. The VI system described in this paper is able to parameterize the test and to control both the test bench and the harvesting hardware. It also conditions and measures electrical signals from the PDUT, and obtains the electrical model of the piezoelectric element. Using this model it is possible to scale both the number of elements and find the optimal topology needed to harvest the required energy by an electronic load.