System Modeling of Piezoelectric Energy Harvesters

For piezoelectric-based, vibration energy harvesting systems, a simplified resonant model is typically used to represent the piezoelectric transducer. Furthermore, the total amount of harvested power is calculated assuming an ideal and lossless power converter. A coupled, system-level model is developed that includes parasitic losses in the power converter for a system comprised of a cantilevered transducer beam and pulsed resonant converter. The accuracy of the system-level model is validated with experimental data, and it is shown that the simplified resonant model underpredicts the total harvested power by approximately 30% for the implemented system. In addition to capturing the electrical domain behavior of the system, the system-level model is also shown to accurately predict the effect of energy harvesting on the beam mechanics.