Finite Element Based System Simulation for Piezoelectric Vibration Energy Harvesting Devices

We present a system simulation approach for piezoelectric vibration
energy harvesting devices. Accurate modeling of the electromechanical
structure is achieved by the finite element method. For consideration of
power electronic circuits as a means of energy extraction, the finite
element model is iteratively coupled to electric circuits via Simulink.
The high computational cost of conventional finite element calculations
is overcome by a specialized modal truncation method for general linear
piezoelectric structures. In doing so, the simulation approach allows
efficient prediction of mechanical quantities (e.g. displacements,
stresses) as well as electric potentials in the continuum under the
influence of arbitrary electrical circuits. Several examples are studied
to validate the truncation approach against analytical models and full
finite element models. The applicability of the method is demonstrated
for a piezoelectric vibration energy harvester in conjunction with a
power electronic circuit.