Modeling of Low Frequency Multi-Source Energy Harvesting Systems

Accurate modeling of multi-source harvesters present design challenges such as the integration of mixed circuit topologies, passive versus active topologies, impedance matching, and optimization. Commercial modeling and simulation software packages offer solutions but often times are not comprehensive enough. In this work P-Spice, Simulink, and Comsol Multiphysics were used to model a multi-source energy harvesting system that incorporates the energy producing capabilities of the piezoelectric, the pyroelectric, and thermoelectric effect. A systems approach that models the material properties of the converters, the power electronics and storage was implemented. Low frequency experimental data from PZT based harvesters and thermoelectric generators were used to produce lumped parameter models. It was demonstrated that within 12% that combining effects may contribute to continuous energy harvesting operation.